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TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYPrelims.indd i 1/22/2010 11:32:03 AMTEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYBiren N. ShahLecturerDepartment of Pharmacognosy and PhytochemistryVidyabharti Trust College of PharmacyUmrakh, GujaratA.K. SethPrincipal and DeanDepartment of PharmacySumandeep Vidyapeeth UniversityVadodara, GujaratELSEVIERA division ofReed Elsevier India Private LimitedPrelims.indd iii 1/22/2010 11:32:05 AMTextbook of Pharmacognosy and PhytochemistryShah and SethELSEVIERA division ofReed Elsevier India Private LimitedMosby, Saunders, Churchill Livingstone, Butterworth Heinemann and Hanley & Belfus are the Health Science imprints of Elsevier. © 2010 ElsevierFirst Edition 2010All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical including photocopying, recording, or any information storage and retrieval system without the prior written permission from the publisher and the copyright holder.ISBN: 978-81-312-2298-0Medical knowledge is constantly changing. As new information becomes available, changes in treatment, procedures, equipment and the use of drugs become necessary. The authors, editors, contributors and the publisher have, as far as it is possible, taken care to ensure that the information given in this text is accurate and up-to-date. However, readers are strongly advised to confirm that the information, especially with regard to drug dose/usage, complies with current legislation and standards of practice. Please consult full prescribing information before issuing prescriptions for any product mentioned in the publication.Published by Elsevier, a division of Reed Elsevier India Private LimitedRegistered Office: Gate No. 3, Building No. A-1, 2, Industrial Area, Kalkaji, New Delhi-110019Corporate Office: 14th Floor, Building No. 10B, DLF Cyber City, Phase II, Gurgaon-122002, Haryana, IndiaCommissioning Editor: Nimisha Goswami Editor: Subodh K. ChauhanManager Publishing Operations: Sunil KumarManager Production: N.C. PantLaser typeset by Chitra Computers, New Delhi.Printed and bound at Rajkamal Electric Press, Kundli, HaryanaPrelims.indd iv 1/22/2010 11:32:05 AMPrefaceTextbook of Pharmacognosy and Phytochemistry is the outcome of numerous efforts of authors to assimilate the voluminous knowledge of traditional and modern pharmacognosy, which has long been a requirement of the curricula of various universities across the world.In times of yore, pharmacognosy was considered as the study of drugs of natural origin. The American Society of Pharmacognosy derived it as the study of physical, chemical, biochemical and biological properties of drug, drug substances or potential drugs or drug substances of natural origin as well as the search for new drugs from natural sources. The world of pharmacognosy has continuously been enriching with multifaceted information considering various aspects of the natural drugs including history, alternative medicinal systems, classification, morphology, identification, cultivation, collection, production and utilization of drugs; trade and utilization of medicinal and aromatic plants and their contribu-tion to national economy; adulteration of drugs of natural origin; evaluation of drugs by their physical, chemical and organoleptic properties; biological screening of herbal drugs; biosynthetic pathways of various phytopharmaceuticals; pharmacognostical study of crude drugs; extraction, isolation and purification of herbal drugs and modern plant biotech-nology. Such an enormous information about the natural drug gives rise to a subject that is now recognized as modern pharmacognosy. It is a highly interdisciplinary science, encompassing a broad range of studies involving phytochemical study of medicinal plants and biologically active principles obtained from plants in addition to the traditional pharma-cognostical aspects of natural drugs.Considering all this comprehensive information of the subject, a textbook is premeditated to contribute substantially to the world of pharmacognosist. This modern book of pharmacognosy and phytochemistry emphasizes the biodiversity of plants and encompasses biosynthesis, extraction, isolation of compounds with TLC identification, bioactivity determina-tion and synthesis of plant components of interest in addition to the traditional pharmacognosy comprising cultivation, collection, morphology, microscopy, taxonomy, chemical constituents and uses of drugs of natural origin. A special feature of the book is an additional advantage, that of inclusion of marketed products of the drugs described.The book is designed to have 35 chapters divided into 10 parts (A to J). Each chapter is written with the aim to give a reasonable background to academician and researchers in the respective topic. A special miscellaneous chapter has been devoted to provide information about ayurvedic, marine medicinal plants, neutraceuticals and cosmeceuticals as well as herbs that have proved to be pesticides or allergens or producing colours, dyes and hallucinogenic effects. The objective of the authors is fully achieved by systemic assemblage of the well-written chapters with neat and clean well-labelled diagrams wherever necessary. The authors convey the deep sense of gratitude to their grandparents, parents, spouses and children for motivating them to provide a kind of book badly required collectively for undergraduate, postgraduate and researchers at one place. This is an added advantage the book will give to the readers of any walk of life.Doubtless, authors are indebted to all who have supported in giving this present shape to the book. Last but not the least, authors are immensely thankful to our publisher for their support, guidance and cooperation to publish this book.Suggestions and criticisms will always be solicited by the authors to further improve the quality of the book in real sense.—AuthorsPrelims.indd v 1/22/2010 11:32:05 AMContentsPreface vPART – A Introduction to Pharmacognosy 1–26Chapter 1 History, Definition and Scope of Pharmacognosy 3–9Chapter 2 Alternative Systems of Medicines 10–21Chapter 3 Classification of Drugs of Natural Origin 22–26PART – B Pharmaceutical Botany 27–65Chapter 4 Morphology of Different Parts of Medicinal Plant 29–56Chapter 5 Study of Different Families 57–65PART – C Cultivation, Collection, Production and Utilization of Herbal Drugs 67–104Chapter 6 Cultivation, Collection and Processing of Herbal Drugs 69–87Chapter 7 Indian Trade in Medicinal and Aromatic Plants 88–94Chapter 8 Utilization of Aromatic Plants and Derived Products 95–100Chapter 9 Role of Medicinal Plants on National Economy 101–104PART – D Analytical Pharmacognosy 105–138Chapter 10 Drug Adulteration 107–109Chapter 11 Evaluation of Crude Drugs 110–114Chapter 12 Biological Screening of Herbal Drugs 115–138PART – E Biogenesis of Phytopharmaceuticals 139–155Chapter 13 General Biosynthetic Pathways of Secondary Metabolites 141–155PART – F Pharmacognostical Study of Crude Drugs 157–403Chapter 14 Drugs Containing Carbohydrates and Derived Products 159–184Chapter 15 Drugs Containing Alkaloids 185–231viii CONTENTSChapter 16 Drugs Containing Glycosides 232–279Chapter 17 Drugs Containing Volatile Oils 280–317Chapter 18 Drugs Containing Resins 318–341Chapter 19 Drugs Containing Lipids 342–361Chapter 20 Drugs Containing Tannins 362–376Chapter 21 Enzymes and Protein Drugs 377–387Chapter 22 Fibres, Sutures and Surgical Dressings 388–398Chapter 23 Drugs of Mineral Origin 399–403PART – G Extraction, Isolation and Purifi cation of Herbal Drugs 405–433Chapter 24 General Methods for Extraction, Isolation and Identification of Herbal Drugs 407–416Chapter 25 Isolation of Phytopharmaceuticals 417–433PART – H Medicinal Plant Biotechnologyas spot diagnosis with the help of simple, modern gadgets.TreatmentDiseases are treated in the following ways: 1. Ilajbil Tadbeer (Regimental Therapy): Some drugless regimens are advised for the treatment of certain ailments, i.e. exercise, massage, hamam (Turkish bath), Douches (Cold and Hot) and the Regimen for Geriatrics. 2. Ilajbil Ghiza (Dietotherapy): Different diets are recom-mended for the patients of different diseases. 3. Ilajbil Dava (Pharmaco therapy): The basic concept of treatment is to correct the cause of the disease that may be abnormal temperament due to: Environmental factors �Abnormal humours either due to internal causes �or external causes which may be pathogenic microorganism, through (a) drugs of opposite temperament to the temperament of the disease that is called Ilaj-bil-zid or (b) drugs of similar temperament as of the temperament of the disease that is called as Ilaj-bil-misl 4. Ilajbil Yad (Surgery).The drugs used are mostly of the plant origin. Some drugs of animal and mineral origin are also used. Patients are treated either by single drug (crude drugs) or by com-pound drugs (formulations of single drugs).There are two types of compound drugs used in the treatment of the diseases, i.e. classical compound drugs which are in use for the hundreds and thousands years and patent/proprietary compound drugs which have been formulated by the individuals or institutions as per their research and experiences. Unani system of medicine is one of the oldest systems of medicine in the world; it is still popular and practised in Indian subcontinent and other parts of the world.2.6. HOMEOPATHIC SYSTEM OF MEDICINEHomoeopathy is a specialized system of therapeutics, developed by Dr Samuel Christian Friedrich Hahnemann (1755–1843), a German physician, chemist and a phar-macist, based on natural law of healing: Similia Similibus Curantur, which means ‘Likes are cured by likes’.Homois means like (similar) and pathos means treatment. Thus, Homoeopathy is a system of treating diseases or suf-fering by the administration of drugs that possess power of producing similar suffering (diseases) in healthy human beings. Dr Hahnemann believed that symptoms are no more than an outward reflection of the body’s inner fight to overcome illness: it is not a manifestation of the illness itself. This law of similar for curing diseases has being in use since the time of Hippocrates, father of medicine. But it was Dr Hahnemann who developed it in to a complete system of therapeutics enunciating the law and its applica-tion in 1810.Fundamental Principles of HomoeopathyEvery science has certain basic principles that guide the whole system. Homoeopathy as a science of medical treat-ment has a philosophy of its own, and its therapeutics is based on certain fundamental principles that are quite distinct and different from those of other school of medical science. These fundamental principles were discussed by Hahnemann in different sections of his medicine and philosophy.They are as follows: 1. Law of Similia. 2. Law of Simplex. 3. Law of minimum. 4. Drug proving. 5. Drug dynamization or potentization. 6. Vital force. 7. Acute and Chronic Diseases. 8. Individualization. 9. Direction of cure.Law of similiaThe therapeutic law on which homoeopathy is based is Simillia Similibus Curentur, which means ‘Let likes be cured by likes’. In this art of healing, the medicine administered to a diseased individual is such that if given to a healthy person it produces same sufferings (diseases) as found in the diseases individual. Thus, the symptoms of the diseased individual are to be matched with the pathogenesis of the medicine, and the medicines which are most similar, viz. Simillimum is selected and administered with certainty to cure.Law of simplexSimple and single drugs should be prescribed at a time. Thus, medicines are proved on healthy human beings singly and in simple form without admixture of any other substance.Law of minimumDrugs are administered in a minimum quantity because of hypersensitivity in disease and the action of drug is always directed towards normal by virtue of altered receptivity of tissue to stimuli in disease. The medicines are just required to arouse a reaction in the body. If they are given in large doses, they cause physiological action producing unwanted side effects and organic damage. The minutest quantity Chapter-02.indd 16 10/12/2009 3:49:28 PM17ALTERNATIVE SYSTEMS OF MEDICINEof medicine helps it to reach the disease, which is of very subtle in nature. The curative action of drug can only be expected without any unwanted aggravation by using minimum quantity of medicine.Drug provingTo apply drugs for therapeutic purposes, their curative power should be known. The curative power of a drug is its ability to produce disease symptoms when employed on a healthy person. The curative power of a drug is known by its pathogenesis and is ascertained by proving the drug singly on healthy human being. This serves the only true record of the curative properties of drug.Drug dynamization or potentizationDisease is a disturbance or deviation in the normal har-monious flow of life force which is dynamic in nature. Now medicine used to encounter disease should also have dynamic action to act on the dynamic disturbance of life force. Therefore, the drugs are dynamized or potentized liberating their dynamic curative power which lies dormant in them. This dynamization is done by the process of Trituration (in case of insoluble substances) or Succession (in case of soluble substances).Preparation of potenciesThe potency can be prepared by three different scales, like decimal scale, centesimal scale and millesimal scale.Decimal scaleThis scale was introduced by Dr Constantive Bering. In this scale, the first potency should contain 1/10 part of original drug. The second potency will contain 1/10 part of the first potency, and so on. The potency in this scale is denoted by suffixing the letter ‘X’ to the number indicating the potency, i.e. the first potency is 1X, the second potency is 2X, and so on.Centesimal scaleIn this scale the first potency should contain 1/100 of original drug and the second potency will contain 1/100 of the first potency, and so on. The potency in this scale is denoted by suffixing the letter ‘C’ to the number indicating the potency. In practice, it is generally denoted by a simple numerical 1C potency equivalent to 2X potency and 2C potency is equivalent to 4X, and so on.Millesimal scaleIn this scale, the first potency should contain 1/50,000 part of the original drug and second potency will contain 1/50,000 of the first potency, and so on. Potency in this scale is denoted by I, II, V, X, etc., or 0/1, 0/2, 0/5, 0/10, etc. In this scale potency 0/2 is equivalent to 4C = 8X, 0/4 = 8C = 16X and so on. Preparation of potency through trituration is made by either decimal or centesimal, and the preparation of potency though succession is made by decimal, centesimal and millesimal.Vital forceDisease is nothing but the disharmonious flow of the vital force giving rise to abnormal sensation and functions (symp-toms and signs). In order to restore the health, the disor-dered vital force is to be brought back to normal. Disease and health are two different quantitative states of this vital force of living being, and cure is to be affected here. Vital force has the following characteristics: spiritual, autocratic, automatic, dynamic, unintelligent and instinctive.Acute and chronic diseasesThe diseases are classified into these types depending upon their onset, nature of progress and termination of diseases.IndividualizationNo two individuals are alike in the world, so the diseases affecting individuals can never be the same assuming the unique individual picture in each diseased individual.Thus, medicines can never be prescribed on the basis of the name of the disease without individualizing each case of disease.Direction of cureDr. Hering states that ‘cure takes place within outward from above to downward and the symptoms disappears in the reverse of their appearance’. If the direction is reverse of that stated then it is not cure but suppression which has occurred.2.7. AROMATHERAPYThe word aromatherapy means treatment using scents. It refers to the use of essential oils in Holistic healing to improve health and emotional well being, and in restoring balance to the body. Essential oils are aromatic essences extracted from plants, flowers, trees, fruit, bark, grasses and seeds.There are more than 150 types of oils that can be extracted. These oils have distinctive therapeutic, psycho-logical and physiological properties that improve health and prevent illness. All essential oils have unique healing and valuable antiseptic properties. Some oils are antiviral, antiinflammatory, pain relieving, antidepressant, stimulat-ing, relaxing, expectorating, support digestion and have diuretic properties too.Essential oils get absorbed into our body and exert an influence on it. The residue gets dispersed from the body naturally. They can also affect our mind and emotions. They enter the body in three ways: by inhalation, absorp-tion and consumption.Chemically, essential oils are a mixture of organic com-pounds like ketones, terpenes, esters, alcohol, aldehyde and hundreds of other molecules which are extremely difficult to classify, as they are small and complex. The essential oils molecules are small. They penetrate human skin easily and enter the bloodstream directly and finally get flushed out through our elementary system.Chapter-02.indd 17 10/12/2009 3:49:28 PM18 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYA concentrate of essential oils is not greasy; it is more like water in texture and evaporates quickly. Some of them are light liquid insoluble in water and evaporate instantly when exposed to air. It would take 100 kg of lavender to get 3 kg of lavender oil; one would need 8 million jasmine flowers to yield barely 1 kg of jasmine oil.Some of the common essential oils used in aromatherapy for their versatile application are: 1. Clary Sage (Salvia scared) 2. Eucalyptus (Eucalyptus globulus) 3. Geranium (Pelargonium graveolens) 4. Lavender (Lavendula limon officinalis) 5. Lemon (Citrus limon) 6. Peppermint (Mentha piperita) 7. Rosemary (Rosmarinus officinalis)Origin of AromatherapyThe title Aromatherapy was coined by Gattefosse, a French chemist in the year 1928. He identified the use of aromatic oils accidentally, when he burned his hand while working in his lab, and immediately he pooled his hand inside a bottle containing lavender oil. The burn healed quickly due to lavender oil and left little scarring. The use of aroma oil is known to be as old as 6,000 years back, when the God of Medicine and Healing, recommended fragrant oils for bathing and massaging. In 4,500 B.C., Egyptians used myrrh and cedar wood oils for embalming their dead and the modern researchers after 6,500 years proved the fact that the cedar wood contains natural fixative and strong antibacterial and antiseptic properties that preserved their mummies.The Greek father of medicine, Hippocrates, recom-mended regular aromatherapy baths and scented massages. Romans utilized essential oils for pleasure and to cure pain and also for massages. During the great plague in London in 1665, people burnt bundles of lavender, cedar wood and cypress in the streets and carried poises of the same plants as their only defence to combat infectious diseases.Aromatherapy has received a wider acceptance in the early twentieth century. Dr Jean Volnet, French army surgeon extensively used essential oils in World War II to treat the injured warriors. It was Madame Morquerite Murry (1964), who gave the holistic approach to aroma oils by experimenting with them for individual problems.Today, researches have proved the multiple uses of aroma oils. Medical research in the recent years has uncovered the fact that the odours we smell have a significant impact on the way we feel. Smells act directly on the brain like a drug. For instance, smelling lavender increases alpha wave frequency in the back of the head, and this state is associ-ated with relaxation.Mode of Action of Aroma OilsDr Alan Huch, a neurologist, psychiatrist and also the director of Smell and Taste Research Centre in Chicago says, ‘Smell acts directly on the brain, like a drug’. Our nose has the capacity to distinguish 1,00,000 different smells, many of which affect us without our knowledge regarding the same.The aroma enters our nose and connects with cilia, the fine hair inside the nose lining. The receptors in the cilia are linked to the olfactory lobe which is at the end of the smell tract. The end of the tract is in turn connected to the brain itself. Smells are converted by cilia into electrical impulses that are transmitted to the brain through olfactory system. All the impulses reach the limbic system. Limbic system is that part of the brain, which is associated with our moods, emotions, memory and learning. All the smell that reaches the limbic system has a direct chemical effect on our moods. The molecular sizes of the essential oils are very tiny and they can easily penetrate through the skin and get into the blood stream. It takes anything between a few seconds to two hours for the essential oils to enter the skin, and within four hours, the toxins get out of the body through urine, perspiration and excreta.Aroma oils work like magic for stress-related prob-lems, psychosomatic disorders, skin infections, hair loss, inflammations and pains arising from muscular or skeletal disorders.Essential oils are safe to use. The only caution being they should never be used directly because some oils may irritate sensitive skin or cause photosensitivity. They should be blended in adequate proportion with the carrier oils. A patch test is necessary to rule out any reactions.Application Methods: Essential oils can be utilized in a myriad of ways, such as topically, ingesting or internal and the most common inhalations.Topical Applications: When using natural products, only your body knows how it is going to respond; therefore, watch for any signs of skin irritation or side effects. Essential oils are soluble with the lipids found in the skin and can penetrate the skin surface and be absorbed into the lymph and circulatory systems. They may be worn as perfumes, ointments, cologne, and can be applied undiluted or diluted using a carrier oil or other base. As a rule, due to the con-centrated and potency of pure essential oils, dilution in a carrier is highly recommended for beginners or for those people with sensitive, fair skin, or applications of the face, neck and other sensitive areas and also if you are trying a new oil or blend of oils. Please be careful with children or infants as the dilution’s necessary are very minute. When in doubt, always consult.Baths: Seven to eight drops of essential oil in 30 ml of carrier oil or honey. Add this to running water and mix well before getting in. Be sure to check the safety info for the essential oils that you choose.Foot baths: Up to six drops in a bowl or footbath of warm water. Soak for approx. 10 minutes. This is great for varicose veins, swollen ankle or tired aching legs.Chapter-02.indd 18 10/12/2009 3:49:28 PM19ALTERNATIVE SYSTEMS OF MEDICINECompresses: Hot or cold. Five to eight drops of essential oil in a basin filled with either hot or cold water. Agitate the water and place a cotton cloth on top of the water to collect the floating oil. Gently squeeze excess water out and apply directly and immediately to affected area. Wrap another towel overthe compress and leave until it reaches body temperature. This can be repeated over and over for relief of pain, headache or to reduce inflammation.Massage: Add 15–22 drops of essential oil to a 30 ml of carrier oil for a full body massage. Always massage in an upward motion and towards the heart for best effect.Inhalation Applications: This is one of the simplest and effective methods of dispersing essential oils into the air. Inhalations are a method of introducing essential oils to the lungs via the nose and throat. This can have great benefit for respiratory problems, sinus congestion, flu, coughs, colds, catarrh and sore throats. Use this method once or twice a day.Facial Steams: Two to three drops of oil into a bowel of boiled water. Drape a towel over your head and lean over the bowl to inhale the steam deeply while keeping eyes shut. Inhale slowly at first, then breathe deeper and deeper. Breathe through your mouth for throat problems, and inhale through your nose for sinus congestion.Atomizers: Add 12–20 drops of essential oils to distilled water in a spray bottle. Shake well before using and mist on face or into the air.Vaporizers: 10–12 drops in the top of the vaporizer for a normal size room.Nebulizers: This electrical unit is designed to disperse the essential oils in a micro-fine mist. This means that the molecules of oil will hang in the air for much longer due to the minuscule weight of the particles. Research has shown that diffusing in this way may help to reduce bacteria, fungus, mold and unpleasant odours. It not only makes the air fresh, but it also helps you to relax, relieves tension and creates an atmosphere of harmony and peace-ful tranquillity.Direct Inhalation: Put 3 drops of essential oil into the palm of your hand and rub hands together briefly, and then quickly inhale deeply for greater inhalation. Relieves sinus congestion and is quite invigorating.Essential oils have being used by the people for thou-sand years; it has great potential to use in modern days. Appropriate method of cultivation and distillation certainly yield good quality essential oil. The more an essential oil is interfered physically or chemically, the less clinical value it will have. This can be overcome by means of suitable evaluation technique.2.8. BACH FLOWER REMEDIESBach flower remedies were discovered by Dr Bach, renowned physician in London who in 1930 gave up his practice to devote all of his time to the search for a new method of healing. For many years he had sought a natural and pure way to heal people; he had discovered how different people reacted differently to the exact same disease. One could be cheerful and hide his worries while another would be very depressed with no hope for tomor-row. Dr Bach believed that those two patients should be treated differently, not strictly according to the disease, but according to their emotions. It was in 1928 Dr Bach discovered the first 38 essences and started to adminis-ter them to his patients, with immediate and successful results. Each of the 38 remedies discovered by Dr Bach is directed at a particular characteristic or emotional state. The cheerful patients would acknowledge their worries, and the depressed patients would regain hope. The essences restored their emotional balance allowing their bodies to heal themselves.The 38 plants and their indications are as follows:Ag � rimony for people who put a brave face on their troublesAspen for people who are anxious or afraid but don’t �know whyBeech for people who are intolerant and critical of �othersCentaury for people who allow others to impose on �themCerato for people who doubt their own judgment �Cherry Plum for uncontrolled, irrational thoughts and �the fear of doing something awfulChestnut Bud for people who repeat mistakes and don’t �learn from experienceChicory for over-possessive, selfish people who cling �to their loved onesClematis for day dreamers �Crab Apple for those who dislike something about the �way they look and as a general cleanserElm for responsible, capable people who in a crisis doubt �their ability to copeGentian for people disheartened when something goes �wrongGorse for people who have lost hope, often without �causeHeather for talkative types who are obsessed with their �own problemsHolly for negative feelings of hatred, envy, jealousy and �suspicionHoneysuckle for people who live in the past �Hornbeam for mental tiredness at the thought of a �coming taskImpatiens for impatience and irritation at other people’s �slownessLarch for fear of failure and lack of confidence �Mimulus for people who are afraid of something real �that they can nameChapter-02.indd 19 10/12/2009 3:49:28 PM20 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYMustard for gloom and depression with no known �causeOak for strong, indefatigable people who can over-extend �themselves by trying too hardOlive for people physically drained by exertion or �illnessPine for those who blame themselves when things go �wrongRed chestnut for excessive worry about the welfare of �loved onesRock rose for extreme fright and terror �Rock water for people whose self-discipline and high �standards are carried to excessScleranthus for peop � le who find it hard to choose between possible courses of actionStar of Bethlehem for sudden frights and shock �Sweet chestnut for utter despair and anguish �Vervain for enthusiastic people who are always on the �goVine for domineering people �Walnut to help protect against outside influences and �the effects of changeWater violet for private, reserved people who can appear �proud and arrogantWhite chestnut for persistent worrying thoughts �Wild oat for people unable to find a direction for their �livesWild rose for people who resign themselves without �complaint or effort to everything life throws at themWillow for people who are full of self-pity, resentment �and bitternessDr Bach’s remedies are still made today at the Bach Centre, Mount Vernon, in England. Since 1991, practitio-ner courses have been running at the Centre and are now running in the United States, Canada, Spain, Holland and Ireland as well. As a result more than 350 trained practi-tioners are now registered with the Centre.2.9. TIBETAN SYSTEM OF MEDICINETibetan medicine is an ancient synthesis of the art of healing, drawing on the knowledge of medical systems existing in a wide region of Southeast and Central Asia. The history of Tibetan medical system dates back to some 3,800 years to the time of the non-Buddhist culture of Tibet’s native religion. It has continued to evolve since then to the time of the strong emergence of Buddhist culture in India. The Tibetans made use of their countries abundant natural resources of flora and fauna to fight against diseases. The seventh and eighth century observed the real development in the field of Tibetan medicine. Ayurveda has contributed a great deal in enriching Tibetan medicine. The Gyudshi or the Four Great Tantras is the most authoritative classic of Tibetan medicine,and bears ample proof of its loyal allegiance to Ayurvedic classics like Charaka, Susruta and Astanga hydra of Vaghbhata. One of the unique features of Tibetan medical system is its ideological structure of medical theory and practice in the image of a tree known as Allegorical Tree.Like the phenomena of conditioned existence, diseases are also the product of causes and conditions. There are two main causes of the disease: a long-term cause and short-term cause. Ignorance or unawareness is the ultimate cause of all diseases. Because of ignorance or delusion, one cannot see the reality of the phenomena and thereby clings to personal self or ego which in turn gives rise to the three mental poisons: desire, hatred and stupidity. So ignorance and three mentalpoisons constitute the long-term cause of disease. Secondly, the short-term causes of disease are the three humours: wind energy (Tib. rlung), bile energy (Tib. mkhris pa) and phlegm (Tib. bad kan). They are produced by the three mental poisons: desire gives rise to wind, hatred to bile and stupidity to phlegm. These three humours constitute the basic energy system in the body. They are interrelated to all vital functions of the body, organs, seven constituents and three excretions. Seven constituents of the body are: food (nutrition), blood, flesh, fat, bone, marrow and semen. The three excrements are sweat, urine and faeces.When the three humours, seven body constituents and the three excrements are balanced, one is healthy; when they are unbalanced one becomes sick. There are four factors responsible for the imbalance; they are improper climate, influence of demons, improper diet and improper behaviour. Since everything is interrelated, imbalance in one organ or one of the humours affects the rest of the organism. Because of the interdependence of humours and body constituents, etc., their imbalance can be diagnosed by the methods specially used by Tibetan doctors. The methods are:InterrogationConsidering the patient’s history.Visual ExaminationVisual examination consists of examining the patient’s physical structure, eyes, tongue, urine, etc.Tactile ExaminationThis method of diagnosis is concerned with things such as temperature, inflammations, etc. Most important here is diagnosis by pulse.TreatmentsThere are four methods of treatment. They are diet, behav-iour modification, medicine and physical therapy. The most Chapter-02.indd 20 10/12/2009 3:49:29 PM21ALTERNATIVE SYSTEMS OF MEDICINEimportant therapeutic technique is to restore the balance of the three ‘NYES-PA’ (humours) and to ensure that the seven constituents of the body are always in a healthy state. These seven constituents are: essential nutrient (dangsma), blood (khark), fat (tsil), muscle tissues (sha), bone (rus), marrow (kang) and regenerative fluid (khuwa).DietThe first treatment involves the prescribing of a proper diet. For example, if the patient is suffering from a bile disorder, he should not take alcohol and should drink cool boiled water.Behaviour ModificationFor example, a patient with a bile disorder should not do heavy physical activities. He should rest in the shade, and not sleep during the day. If these two factors fail to bring about a positive result, further treatment should be carried out.MedicinePrescription of natural drugs. Here again the physician starts with less-potent concoctions and turns to stronger forms, if necessary. The drugs can be classified in 10 forms: decoction, pills, powder, granules, medicinal butter, medici-nal calxes, concentrated extractions, medicinal wine, gem medicine and herbal medicine.Physical TherapyApart from natural drugs, the physician may also have to depend on other therapeutic techniques, like massage, hot and cold compresses, mineral spring bath therapy and medici-nal bath are the gentle techniques. Blood, letting, cauteriza-tion, moxibustion, cupping and golden needle therapy are considered as rough techniques. There is also some minor surgery such as the draining of abscesses.Tibetan medical philosophy is a holistic philosophy involving the harmonious operation and balance of all the energies that constitute the human psycho-physical being. Theses energies are the psychologically originating three ‘NYES-PA’ or humours, which correspond to the three mental poisons and the five cosmo-physical energies that are at the basis of all phenomena. If all the factors that influence these energies (seasonal factors; diet and nutrition, life style and mental attitudes) are positively disposed, then these energies remain in balanced operation, and health is experienced. It is the objective of Tibetan medicine that the balance in these energies should be maintained.Chapter-02.indd 21 10/12/2009 3:49:29 PM3.1. INTRODUCTIONThe flora and fauna of mother earth has a great diversity. The number of plant species divided in about 300 families and 10,500 genera are supposed to be about 2–2.5 lacs. At least 100–150 species of medicinal plants are currently cultivated and about 30–40 of them are the large-scale field corps. Drugs of the animal and mineral origin have also been used since the beginning and even today many such crude drugs are important, commercial products. All these drugs of natural origin have been used as the curative agents and even in this age of scientific discoveries and invention, natural drug have been the primary choice as a source of drug. Human inquisitiveness has gone beyond the terrestrial regions and exploited the seas and oceans which contain about 5 lacs species of marine organisms. Therapeutically active constituents found in these organ-isms open yet another great natural source of drugs of unending search.Crude drugs can be regarded as the substances either used directly or indirectly as a drug which have not been changed or modified in its chemical composition.The crude drugs of natural origin can be divided into two main categories as organized crude drugs and unor-ganized crude drugs. Organized DrugsOrganized drugs consist of the cellular organization in the form of anatomical features. These are mostly the crude drugs from plant sources. Almost all of the morphologi-cal plant parts or the entire plant itself can be called as an organized drugs. A long list can be made of such crude drugs. To mention few of them, like, Cinchona bark, Sandalwood, Quassia wood, Senna, Digitalis leaves, Nux vomica seeds, Rauwolfia roots and many other examples of above-mentioned groups or crude drugs exemplified by some other morphological organs can be quoted as the example of organized crude drugs.Microscopical and anatomical studies are preeminent for such crude drugs. These can be used directly in medicine or can be used by modifying or by extracting the active ingredient from it. The simple medicines prepared from these drugs are herbal teas, extracts, tinctures, etc., and it may be extensively processed for the isolation and purifi-cation of pure therapeutically active constituent which is ultimately responsible for the action of the drug.Unorganized DrugsThe unorganized drugs do not have the morphological or anatomical organization as such. These are the products which come directly in the market but their ultimate source remains the plants, animals or minerals. Micro-scopical studies are not required for such crude drugs. These includes products like plant exudates as gums, oleogums, oleogumresins, plant lattices like that of opium, aloetic juices like aloes or dried extracts of black and pale catechu, agar, alginic acid, etc., are products coming under this group. Other products like essential oils, fixed oils, fats and waxes obtained from vegetable or animal sources, although hydro-distilled or extracted from plant, become the direct commodity for use. Unorganized crude drugs may be miscellaneous mineral products like shilajit. These products may be solid, semisolid or liquid and the physi-cal, chemical and analytical standards may be applied for testing their quality and purity.3.2. CLASSIFICATION OF CRUDE DRUGSThe most important natural sources of drugs are higher plant, microbes and animals and marine organisms. Some useful products are obtained from minerals that are both organic and inorganic in nature. In order to pursue (or to follow) the study of the individual drugs, one must adopt some particular sequence of arrangement, and this is referred to a system of classification of drugs. A method of classification should be:Classification of Drugs of Natural OriginCHAPTER3Chapter-03.indd 22 10/12/2009 3:50:00 PM23CLASSIFICATION OF DRUGS OF NATURAL ORIGIN(a) simple, (b) easy to use, and (c) free from confusion and ambiguities. Because of their wide distribution, each arrangement of classification has its own merits and demerits, but for the purpose of study the drugs are classified in the following different ways: 1. Alphabetical classification 2. Taxonomical classification 3. Morphological classification 4. Pharmacological classification 5. Chemical classification 6. Chemotaxonomical classification 7. Serotaxonomical classificationAlphabetical ClassificationAlphabetical classification is the simplest way of classifica-tion of any disconnected items. Crude drugs are arranged in alphabetical order of their Latin and English names (common names) or sometimes local language names (ver-nacular names). Some of the pharmacopoeias, dictionaries and reference books which classify crude drugs according to this system are as follows: 1. Indian Pharmacopoeia 2. British Pharmacopoeia 3. British Herbal Pharmacopoeia 4. United States Pharmacopoeia and National Formu-lary 5. British Pharmaceutical Codex 6. European Pharmacopoeia In European Pharmacopoeia these are arranged according to their names in Latin where in United States Pharmaco-poeia (U.S.P.) and British Pharmaceutical Codex (B.P.C.), these are arranged in English. MeritsIt is easy and quick to use. �There is no repetition of entries and is devoid of con- �fusion.In this system location, tracing and addition of drug �entries is easy. DemeritsThere is no relationship between previous and successive drug entries. Examples: Acacia, Benzoin, Cinchona, Dill, Ergot, Fennel, Gentian, Hyoscyamus, Ipecacuanha, Jalap, Kurchi, Liquorice, Mints, Nux vomica, Opium, Podophyllum, Quassia, Rauwolfia, Senna, Vasaka, Wool fat, Yellow bees wax, Zeodary. Taxonomical ClassificationAll the plants possess different characters of morphologi-cal, microscopical, chemical, embryological, serological and genetics. In this classification the crude drugs are classified according to kingdom, subkingdom, division, class, order, family, genus and species as follows.Class: Angiospermae (Angiosperms) are plants that produce flowers and Gymnospermae (Gymnosperms) which don’t produce flowers.Subclass: Dicotyledonae (Dicotyledons, Dicots) are plants with two seed leaves; Monocotyledonae (Monocotyledons, Monocots) with one seed leaf.Superorder: A group of related plant families, classified in the order in which they are thought to have developed their dif-ferences from a common ancestor. There are six superorders in the Dicotyledonae (Magnoliidae, Hamamelidae, Caryophyl-lidae, Dilleniidae, Rosidae, Asteridae), and four superorders in the Monocotyledonae (Alismatidae, Commelinidae, Arecidae, and Liliidae). The names of the superorders end in –idae.Order: Each superorder is further divided into several orders. The names of the orders end in –ales.Family: Each order is divided into families. These are plants with many botanical features in common, and are the highest classification normally used. At this level, the similarity between plants is often easily recognizable by the layman. Modern botanical classification assigns a type plant to each family, which has the particular characteristics that separate this group of plants from others, and names the family after this plant.The number of plant families varies according to the botanist whose classification you follow. Some botanists recognize only 150 or so families, preferring to classify other similar plants as subfamilies, while others recognize nearly 500 plant families. A widely accepted system is that devised by Cronquist in 1968, which is only slightly revised today. The names of the families end in –aceae.Subfamily: The family may be further divided into a number of subfamilies, which group together plants within the family that have some significant botanical differences. The names of the subfamilies end in –oideae.Tribe: A further division of plants within a family, based on smaller botanical differences, bin still usually comprising many different plants. The names of the tribes end in –eae.Subtribe: A further division based on even smaller botanical differences, often only recognizable to botanists. The names of the subtribes end in –inae.Genus: This is the part of the plant name that is most famil-iar; the normal name that you give a plant—Papaver (Poppy), Aquilegia (Columbine), and so on. The plants in a genus are often easily recognizable as belonging to the same group.Species: This is the level that defines an individual plant. Often, the name will describe some aspect of the plant—the colour of the flowers, size or shape of the leaves, or it may be named after the place where it was found. Together, the genus and species name refer to only one plant, and they are used to identify that particular plant. Sometimes, the species is further divided into subspecies that contain Chapter-03.indd 23 10/12/2009 3:50:01 PM24 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYplants not quite so distinct that they are classified as variet-ies. The name, of the species should be written after the genus name, in small letters, with no capital letter.Variety: A variety is a plant that is only slightly different from the species plant, but the differences are not so insig-nificant as the differences in a form. The Latin is varietas, which is usually abbreviated to var. The name follows the genus and species name, with var. before the individual variety name. Form: A form is a plant within a species that has minor botanical differences, such as the colour of flower or shape of the leaves. The name follows the genus and species name, with form (or f.) before the individual variety name.Cultivar: A cultivar is a cultivated variety—a particular plant that has arisen either naturally or through deliberate hybridization, and can be reproduced (vegetatively or by seed) to produce more of the same plant.The name follows the genus and species name. It is written in the language of the person who described it, and should not be translated. It is either written in single quotation marks or has cv. written in front of the name.Kingdom PlantsSubkingdom Tracheobionta—Vascular plantsSuperdivision Spermatophyta—Seed plantsDivision Magnoliophyta—Flowering plantsClass Magnoliopsida—DicotyledonsSubclass Asteridae Order Asterales Family Asteraceae—Aster familyGenus Tridax L.—tridaxMeritsTaxonomical classification is helpful for studying evolution-ary developments. DemeritsThis system also does not correlate in between the chemical constituents and biological activity of the drugs.Morphological ClassificationIn this system, the drugs are arranged according to the morphological or external characters of the plant parts or animal parts, i.e. which part of the plant is used as a drug, e.g. leaves, roots, stem, etc. The drugs obtained from the direct parts of the plants and containing cellular tissues are called as organized drugs, e.g. rhizomes, barks, leaves, fruits, entire plants, hairs and fibres. The drugs which are pre-pared from plants by some intermediate physical processes such as incision, drying or extraction with a solvent and not containing any cellular plant tissues are called unorga-nized drugs. Aloe juice, opium latex, agar, gambir, gelatin, tragacanth, benzoin, honey, beeswax, lemon grass oil, etc., are examples of unorganized drugs.Organized drugsWoods: Quassia, Sandalwood and Red Sandalwood. Leaves: Digitalis, Eucalyptus, Gymnema, Mint, Senna, Spearmint, Squill, Tulsi, Vasaka, Coca, Buchu, Hamamelis, Hyoscyamus, Belladonna, Tea. Barks: Arjuna, Ashoka, Cascara, Cassia, Cinchona, Cin-namon, Kurchi, Quillia, Wild cherry. Flowering parts: Clove, Pyrethrum, Saffron, Santonica, Chamomile. Fruits: Amla, Anise, Bael, Bahera, Bitter Orange peel, Capsicum, Caraway, Cardamom, Colocynth, Coriander, Cumin,Dill, Fennel, Gokhru, Hirda, Lemon peel, Senna pod, Star anise, Tamarind, Vidang. Seeds: Bitter almond, Black Mustard, Cardamom, Colchi-cum, Ispaghula, Kaladana, Linseed, Nutmeg, Nux vomica, Physostigma, Psyllium, Strophanthus, White mustard. Roots and Rhizomes: Aconite, Ashwagandha, Calamus, Calumba, Colchicum corm, Dioscorea, Galanga, Garlic, Gention, Ginger, Ginseng, Glycyrrhiza, Podophyllum, Ipecac, Ipomoea, Jalap, Jatamansi, Rauwolfia, Rhubarb, Sassurea, Senega, Shatavari, Turmeric, Valerian, Squill. Plants and Herbs: Ergot, Ephedra, Bacopa, Andrographis, Kalmegh, Yeast, Vinca, Datura, Centella. Hair and Fibres: Cotton, Hemp, Jute, Silk, Flax. Unorganized drugsDried latex: Opium, Papain Dried Juice: Aloe, Kino Dried extracts: Agar, Alginate, Black catechu, Pale catechu, Pectin Waxes: Beeswax, Spermaceti, Carnauba wax Gums: Acacia, Guar Gum, Indian Gum, Sterculia, Tra-gacenthResins: Asafoetida, Benzoin, Colophony, copaiba Gua-iacum, Guggul, Mastic, Coal tar, Tar, Tolu balsam, Storax, Sandarac. Volatile oil: Turpentine, Anise, Coriander, Peppermint, Rosemary, Sandalwood, Cinnamon, Lemon, Caraway, Dill, Clove, Eucalyptus, Nutmeg, Camphor. Fixed oils and Fats: Arachis, Castor, Chalmoogra, Coconut, Cotton seed, Linseed, Olive, Sesame, Almond, Theobroma, Cod-liver, Halibut liver, Kokum butter. Animal Products: Bees wax, Cantharides, Cod-liver oil, Gelatin, Halibut liver oil, Honey, Shark liver oil, shellac, Spermaceti wax, wool fat, musk, Lactose. Fossil organism and Minerals: Bentonite, Kaolin, Kiess-lguhr, Talc. MeritsMorphological classification is more helpful to identify and detect adulteration. This system of classification is more convenient for practical study especially when the chemical nature of the drug is not clearly understood. Chapter-03.indd 24 10/12/2009 3:50:01 PM25CLASSIFICATION OF DRUGS OF NATURAL ORIGINDemeritsThe main drawback of morphological classification is �that there is no corelation of chemical constituents with the therapeutic actions.Repetition of drugs or plants occurs. �Pharmacological ClassificationGrouping of drug according to their pharmacological action or of most important constituent or their therapeutic use is termed as pharmacological or therapeutic classification of drug. This classification is more relevant and is mostly a followed method. Drugs like digitalis, squill and strophan-thus having cardiotonic action are grouped irrespective of their parts used or phylogenetic relationship or the nature of phytoconstituents they contain.Sl. No.Pharmacological categoryExample1. Drug acting on G.I.T.BitterCarminativeEmeticAntiamoebicLaxativePurgative CatharticCinchona, Quassia, GentianFennel, Cardamom, MenthaIpecacKurchi, IpecacAgar, Isabgol, BananaSenna, Castor oilSenna2. Drug acting on Respiratory systemExpectorantAntitussive BronchodilatorsVasaka, Liquorice, IpecacOpium (codeine)Ephedra, Tea3. Drug acting on Cardiovascular systemCardio tonicCardiac depressantVasoconstrictorAntihypertensiveDigitalis, Strophanthus, SquillCinchona, VeratrumErgotRauwolfi a4. Drug acting on Autonomic nervous systemAdrenergicCholinergicAnticholinergicEphedraPhysostigma, PilocarpusDatura, Belladonna5. Drug acting on Central nervous systemCentral analgesicCNS depressantCNS stimulantAnalepticOpium (morphine)Belladonna, Opium, HyoscyamusTea, CoffeeNuxvomica, Camphor, Lobelia6. Antispasmodic Datura, Hyoscyamus, Opium, Curare7. Anticancer Vinca, Podophyllum, Taxus 8. Antirheumatic Aconite, Colchicum, Guggal9. Anthalmintic Quassia, Vidang10. Astringent Catechu, Myrobalans11. Antimalarial Cinchona, Artemisia12. Immunomodulatory Ginseng, Ashwagandha, Tulsi13. Immunizing agent Vaccines, Sera, Anti toxin14. Drug acting on skin membraneBeeswax, Wool fat, Balsam of Tolu, Balsam of Peru15. Chemotherapeutic Antibiotics16. Local Anesthetic CocaMerits This system of classification can be used for suggesting substitutes of drugs, if they are not available at a particular place or point of time. DemeritsDrugs having different action on the body get classified separately in more than one group that causes ambiguity and confusion. Cinchona is antimalarial drug because of presence of quinine but can be put under the group of drug affecting heart because of antiarrhythmic action of quinidine.Chemical ClassificationDepending upon the active constituents, the crude drugs are classified. The plants contain various constituents in them like alkaloids, glycosides, tannins, carbohydrates, saponins, etc. Irrespective of the morphological or taxonomical char-acters, the drugs with similar chemical constituents are grouped into the same group. The examples are shown in this table.Sl. No.Chemical constituent groupExamples1. Alkaloids Cinchona, Datura, Vinca, IpecacNux vomica2. Glycosides Senna, Aloe, Ginseng, Glycyrrhiza, Digitalis3. Carbohydrates and its derived productsAcacia, Tragacanth, Starch, Isabgol4. Volatile oil Clove, Coriander, Fennel, Cinnamon, Cumin5. Resin and Resin combinationBenzoin, Tolu Balsam, Balsam of peru6. Tannins Catechu, Tea7. Enzymes Papain, Caesin, Trypsin8. Lipids Beeswax, Kokum butter, LanolinMeritsIt is a popular approach for phytochemical studies.DemeritsAmbiguities arise when particular drugs possess a number of compounds belonging to different groups of compounds.Chemotaxonomical ClassificationThis system of classification relies on the chemical similarity of a taxon, i.e. it is based on the existence of relationship between constituents in various plants. There are certain types of chemical constituents that characterize certain classes of plants. This gives birth to entirely a new concept of chemotaxonomy that utilizes chemical facts/characters Chapter-03.indd 25 10/12/2009 3:50:01 PM26 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYfor understanding the taxonomical status, relationships and the evolution of the plants. For example, tropane alkaloids generally occur among the members of Solanaceae, thereby, serving as a chemot-axonomic marker. Similarly, other secondary plant metabo-lites can serve as the basis of classification of crude drugs. The berberine alkaloid in Berberis and Argemone, Rutin in Rutaceae members, Ranunculaceae alkaloids among its members, etc., are other examples. It is the latest system of classification that gives more scope for understanding the relationship between chemical constituents, their biosynthesis and their possible action. Serotaxonomical ClassificationThe serotaxonomy can be explained as the study about the application or the utility of serology in solving the taxo-nomical problems. Serology can be defined as the study of the antigen–antibody reaction. Antigens are those sub-stances which can stimulate the formation of the antibody. Antibodies are highly specific protein molecule produced by plasma cells in the immune system. Protein are carri-ers of the taxonomical information and commonly used as antigen in serotaxonomy.It expresses the similarities and the dissimilarities among different taxa, and these data are helpful in taxonomy. It deter-mines the degree of similarity between species, genera, family, etc., by comparing the reaction with antigens from various plant taxa with antibodies present against a given taxon.Serology helps in comparing nonmorphological charac-teristics, which helps in the taxonomical data. This tech-nique also helps in the comparison of single proteins from different plant taxa.Chapter-03.indd 26 10/12/2009 3:50:01 PMPART B PHARMACEUTICAL BOTANYChapter-04.indd 27 10/12/2009 3:50:19 PM4.1. INTRODUCTIONArrangements of plants into groups and subgroups are com-monly spoken as classification. Various systems of classifying plants have gradually developed during past few centuries which have emerged as a disciplineof botanical science known as Taxonomy or Systematic botany. The Taxonomy word is derived from two Greek words ‘Taxis’ meaning an arrangement and ‘nomos’ meaning laws. Therefore, the systemization of our knowledge about plants in an orderly manner becomes subject matter of systematic botany.The aim and objective of taxonomy is to discover the similarities and differences in the plants, indicating their closure relationship with their descents from common ancestry. It is a scientific way of naming, describing and arranging the plants in an orderly manner.The classification of plants may be based upon variety of characters possessed by them. Features like specific morpho-logical characters, environmental conditions, geographical distribution, colours of flowers and types of adaptations or reproductive characteristics can be used as a base for taxonomical character.4.2. HISTORYMany attempts were made in the earlier days to name and distinguish the plants as well as animals. Earliest mentions of classifications are credited to the Greek scientist Aristotle (384–322 B.C.) who is also called as the father of natural history. Aristotle attempted a simple artificial system for classifying number of plants and animals on the basis of their morphological and anatomical resemblances. It worked with great success for more than two thousand years.Theophrastus (370–285 B.C.), the first taxonomist who wrote a systematic classification in a logical form was a student of Aristotle. He attempted to extend the botanical knowledge beyond the scope of medicinal plants. Theophrastus classified the plants in about 480 taxa, using primarily the most obvious morphological characteristics, i.e. trees, shrubs, under-shrubs, herbs, annuals, biennials and perennials. He recognized differences based upon superior and inferior ovary, fused and separate petals and so on. He is called father of botany. Several of the names mentioned by him in his treatise, ‘De Historia Plantarum’ was later taken up by Linnaeus in his system of classification.A. P. de Tournfort (1658–1708) carried further the pro-motional work on genus. He had a clear idea of genera and many of the names used by him in his Institutions Rei Herbariae (1700) were adopted by Linnaeus. Tournfort’s system classified about 9000 species into 698 genera and 22 classes. This system although artificial in nature was extremely practical in its approach.Most of the taxonomists after Tournfort used the rela-tive taxonomic characterization as a basis for classification. This natural base helped to ascertain the nomenclature and also showed its relative affinities with one another. All the modern systems of classification are thus natural systems.John Ray (1682), an English Botanist used a natural system based on the embryo characteristics. Most impor-tant of his works were Methodus Plantarum Nova (1682), Historia Plantarum (1686) and Synopsis Methodica Stirpium Britanicarum (1698). He classified the plants into two main groups: Herbae, with herbaceous stem and Arborae, with woody stem.The main groups of flowerless and flowering plants were subdivided distinctly into 33 smaller groups. He divided flowering plants in monocotyledonae and dicoty-ledonae, which later worked as a great foundation for the further developments of systematic botanyCarrolus Linnaeus (1707–1778), a Swedish botanist, introduced the system of binomial nomenclature. His Morphology of Different Parts of Medicinal PlantCHAPTER4Chapter-04.indd 29 10/12/2009 3:50:20 PM30 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYartificial system was based oh particular names of a substantive and adjective, nature. It is best known as binomial system of nomenclature in which the first general name indicates the genus and the second specific name denotes the species. Linnaeus characterized and listed about 4378 different species of plants and animals in his works Species Plantarum and Genera Plantarum (1753). He classified plants on the basis of reproductive organs, i.e. stamens and carpels—and hence this system is also known as the sexual system of classification. According to this system, plants are divided into 24 classes having 23 phanerogams and one cryptogam. Phanerogams were classified on the basis of unisexual and bisexual flowers. Further classification is based on the number and types of stamens and carpels.A French Botanist A. P. de Candolle (1819) extensively worked and improved the natural system of classification. Along with the recognition of cotyledons, corolla and stamen characteristics, Candolle introduced the arrange-ment of fibrovascular bundles as a major character. He also provided a classification system for lower plants; Candolle mainly divided plants into vascular and cellular groups, i.e. plants with cotyledons and without cotyledons. There groups were further divided and subdivided on the basis of cotyledons and floral characteristics.Bentham and Hooker’s SystemGeorge Bentham (1830–1884) and Joseph Hooker (1817–1911) two British Botanists, adopted a very comprehen-sive, natural system of classification in their published work Genera Plantarum (1862–1883), which dominated the botanical science for many years. It is an extension of Candolle’s work.According to this system, the plant kingdom comprises about 97,205 species of seed plants which are distributed in 202 orders and were further divided in families. Dicoty-ledons have been divided in three divisions on the basis of floral characteristics namely: polypetalae, gamopetalae and mono-chlamydeae—all the three divisions consist-ing of total 163 families. Polypetalae have both calyx and corolla with free petals and indefinite number of stamens along with carpels. Gamopetalae have both calyx and corolla, but the latter is always gamopetalous or fused. Stamens are definite and epipetalous along with carpels. In monochlamydeae flowers are incomplete because of the absence of either calyx or corolla, or both the whorls. It generally includes the families which do not come under the above two subclasses.Following the above scheme of classification Indian senna, Cassia angustifolia and Ginger, Zingiber officinalis may be referred to its systematic position as mentioned in Table 4.1. Table 4.1: Scheme of systematic classifi cation of drugsDivision Phanerogam PhanerogamSubdivision Angiosperm AngiospermClass Dicotyledonae MonocotyledonaeSubclass Polypetalae –Series Calycifl orae EpigynaeOrder Resales ScitamineaeFamily Leguminosae ZingiberaceaeSubfamily Caesalpinieae –Genus Cassia ZingiberSpecies angustifolia offi cinalisBentham and Hookers system of classification was accepted throughout the British Empire and in the United States, and was adapted to lesser extent by Continental botanists. It was regarded as the most convenient and suit-able for practical utility.Adolf Engler (1844–1930), a German Botanist published his system of classification in Die Naturlichen Pflanzenfamilien in 23 volumes, covering the whole plant kingdom. The increasing complexity of the flowers is considered for clas-sification. Engler believed that woody plants with unisexual and apetalous flowers are most primitive in origin. This is a natural system which is based on the relationships and is compatible with evolutionary principles.Hutchinson’s System of ClassificationA British systematic Botanist J. Hutchinson published his work, The Families of Flowering Plants in 1926 on Dicotyle-dons and in 1934 on monocotyledons. Hutchinson made it clear that the plants with sepals and petals are more primitive than the plants without petals and sepals on the assumption that free parts are more primitive than fused ones. He also believed that spiral arrangement of floral parts, numerous free stamens and hermaphrodite flowers are more primitive than unisexual flowers with fused stamens. He consideredmonochlamydous plants as more advanced than dicotyledons. Hutchinson’s system indicates the concept of phylogenetic classification and seems to be an advanced step over the Bentham and Hooker system of classification. Hutchinson accepted the older view of woody and herbaceous plants and fundamentally called them as Lignosae and Herbaceae. He revised the scheme of classifi-cation in 1959. Hutchinson placed the gymnosperms first, then the dicotyledons and lastly the monocotyledons.H. H. Rusby (1931) worked on phylogenic classification. His work is the scathing criticism on the phylogenic system attempted by M. C. Nair, ‘Angiosperm Phylogeny on a Chemical basis.’ While criticizing M. C. Nair, he indicated that the taxonomists need to study and use all the criteria including chemical nature while working on phylogenic system. He stubbornly criticized a publication on Cinchona that when the whole genus has been thoroughly investigated for its morphology; chemistry, reproduction, embryology, Chapter-04.indd 30 10/12/2009 3:50:20 PM31MORPHOLOGY OF DIFFERENT PARTS OF MEDICINAL PLANThorticulture, ecology and geography, all the information is ignored in the chemotaxonomical study which is a great misfortune to Cinchona literature.M.P. Morris (1954) worked on chemotaxonomy of toxic cyanogenetic glycosides of Indigofera endecaphylla and pointed out that p-nitropropionic acid, a hydrolysis product of Hiptagenic acid, occurs in a free state in the plants. His work provided the direction to chemotaxonomy of cyano-genetic principles.4.3. STUDY OF DIFFERENT TISSUE SYSTEMSThe flowering plants have highly evolved organizations which indicate the structural and functional specializa-tion. Externally these organizations may be regarded as the morphological parts, but internally it can be categorized in cells, tissues and tissue systems. The morphologically most easily and clearly recognizable units of the plant body are the cells. The united masses of cells are distinct from one another structurally as well as functionally. Such groupings of cells may be referred to as tissues which further may develop into a simpler or complex cellular organization. The arrangement of various tissues or tissue systems in the plant indicates its specialized nature. For example, vascular tissues are mainly concerned with the conduc-tion of food and water, and for the efficient functioning; a complex network is developed with the places of water intake, sites of food synthesis and with areas of growth, development and storage. In the same way nonvascular tissues are also continually arranged which indicates the specific interrelationship of vascular tissues, storage tissues and supportive tissues. Plant tissues are generally categorized in to two categories.PLANT TISSUEPermanent tissues Merismetic tissues e.g. epidermisSimple tissue Complex tissue Secretory tissueParenchyma Xylem LaticiferousCollenchyma Phloem GlandularSclerenchymaDifference between Merismetic and Permanent TissuesSr. No. Merismetic Tissue Permanent Tissue1. Comprises of young cells which have the power to redivide and multiply.These cells are living or dead having attained their defi nite form and size.2. These cells are present at growing points, i.e. tips of roots, shoots and epidermis.Usually present in the ground tissue and make the fundamental tissue system.3. These cells are closely packed without intracellular spaces.Intracellular spaces are present.In the plant body, the following three tissue systems can be distinguished.(A) Dermal tissue system: It represents the outer most part of the plant which forms a protective covering line. It includes epidermis, periderm, etc.(B) Vascular tissue system: It is concerned with trans-mission of material in the plant and represents stelar structures like xylem and phloem.(C) Ground tissue system: It consists of simple cells which may be strengthened by addition of thickened cells. It represents ground tissue made up of paren-chyma, collenchyma and sclerenchyma.Dermal Tissue SystemEpidermisThe epidermal tissue system is derived from the dermatogen of the apical meristem and forms the epidermis (epi - upon, derma - skin) or outermost skin layer, which extends over the entire surface of the plant body. Epidermis is the out-ermost layer of the plant consisting normally of a single layer of flattened cells. The walls may be straight, wavy or beaded and often covered with a layer of cuticle made up of cutin.StraightwalledWavywalledSlightly wavywalledBeadedwalledFig. 4.1 Different type of cell walls of epidermisFunctions 1. The primary function of the epidermis is protection of the internal tissues against mechanical injury, excessive heat or cold, fluctuations of temperature, attacks of parasitic fungi and bacteria, and against the leaching effect of rain. This is possible due to the presence of cuticle, hairs, tannin, gum, etc. 2. Prevention of excessive evaporation of water from the internal tissues by the development of thick cuticles, wax and other deposition, cutinized hairs, scales, multiple epidermis, etc., is another important func-tion of the epidermis. 3. Strong cuticles and cutinized hairs, particularly a dense coating of hairs, protect the plant against intense illu-mination (i.e. strong sunlight) and excessive radiation of heat. 4. The epidermis also acts as a storehouse of water, as in desert plants. Chapter-04.indd 31 10/12/2009 3:50:20 PM32 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRY 5. The epidermis sometimes has some minor functions like photosynthesis, secretion, etc.StomataStomata are minute openings usually found in the epidermis of the leaves as in Digitalis, Senna, etc., or in young green stems as in Ephedra, in flower as in clove and in fruit as in fennel, orange peel. These openings are surrounded with a pair of kidney-shaped cells called guard cells. The term ‘stoma’ is often applied to the stomatal arrangement, which consists of slit like opening along with the guard cells. The epidermal cells surrounding the guard cells are called neighbouring cells or subsidiary cells. These, in many cases, as in Digitalis resemble the other epidermal cells, but in large number of plants they differ in size, arrangement and shape from the other epidermal cells.Guard cellsStoma (opening)Subsidiary cellsFig. 4.2 StomataTypes of stomatal arrangement: According to the arrangement of the epidermal cells surrounding the stomata, they have been grouped as follows: 1. Diacytic or Caryophyllaceous (cross celled): The stoma is accompanied by two subsidiary cells, the long axis of which is at right angles to that of the stoma. This type of stoma is also, called the Labiatae type as it is found in many plants of the family Labiatae such as vasaka, tulsi, spearmint and peppermint. 2. Anisocytic or Cruciferous (unequal celled): The stoma is surrounded by usually three subsidiary cells of which one is markedly smaller than the others. This type of stoma is also called the Solanaceous type as it is found in many plants of the family Solanaceae, such as Belladonna, Datura, Hyoscyamus, Stramonium, Tobacco; it is also found in many plants of the family Compositae. 3. Anomocytic or Ranunculaceous (irregular celled): The stoma is surrounded by a varying number of cells in no way differing from those of the epidermal cells as in Digitalis, eucalyptus, henna, lobelia, neem, etc. 4. Paracytic or Rubiaceous (parallel celled): The stoma is surrounded usually by two subsidiary cells, the long axis of which are parallel to that of stoma as in Senna and many Rubiaceous plants. 5. Actinocytic (radiate celled): The stoma is sur-rounded by circle of radiating cells, as in Uva ursi.Functions and distributions of stomata: Stomata perform the function of gaseous exchange and transpiration in the plant body.They are most abundant in the lower epidermis of a dorsiventral leaf and less abundant on the upper epidermis. In isobilateral leaves, stomata remain confined to the upper epidermis alone; in submerged leaves no stoma is present. In Buchu and Neem, stomata are present only on lower surface, while in case of Belladonna, Datura, Senna, etc., stomata are present on the both surfaces. The distribution of stoma shows great variation between upper and lower epidermis. In desert plants and in those showing xerophytic adaptations, e.g. Ephedra, Agave, Oleander, etc., stomata are situated in grooves or pits in the stem or leaf. This is a special adaptation to reduce excessive evaporation, as the stomata sunken in pits are protected from gusts of wind.TrichomesTrichomes are more elongated outgrowths of one or more epidermal cells, and consist of two carts, a foot or root embedded in the epidermis and a free projecting portion termed as body. Trichomes usually occur in leaves but are also found to be present on some other parts of the plant Fig. 4.3 Different types of stomataDiacytic(caryophyllaceous)Anisocytic(cruciferous)Anomocytic(ranunculaceous)Paracytic(rubiaceous)ActinocyticChapter-04.indd 32 10/12/2009 3:50:21 PM33MORPHOLOGY OF DIFFERENT PARTS OF MEDICINAL PLANTas in Kurchi, Nux vomica and Strophanthus seeds, Androg-raphis and Belladonna stem, Cummin, and Lady’s finger fruits, etc. Trichomes are rarely present on the leaves of Bearberry, Buchu, Henna, etc., and are absent in glabrous leaves like Coca, Hemlock, Savin, etc.Functions of trichomes: Trichomes or hairs are adapted to many different purposes. A dense covering of trichomes prevents the damage by insects and the clogging of stomata due to accumulation of dust. Trichomes also aid the dispersion of seeds of Milkweed (Asclepias) and Madar (Calotropis), which are readily scattered by wind. In Peppermint, Rosemary, Tulsi, etc., trichomes perform the function of secreting volatile oil.Types of trichomes: Broadly, the trichomes are classi-fied as: 1. Covering trichomes or clothing hairs or nonglandular trichomes and 2. Glandular trichomes Depending upon the structure, shape and number of cells, they are further classified as follows:[A] Covering trichomes(a) Unicellular trichomes1. Linear, strongly waved, thick walled trichomes— Yerba santa2. Linear, thick walled and warty trichomes— Damiana 3. Short. conical trichomes—Tea4. Short, conical, warty trichomes—Senna 5. Large, conical, longitudinally striated trichomes— Lobelia6. Long, tubular, flattened and twisted trichomes—Cotton7. Lignified trichomes—Nux vomica, strophanthus8. Short, sharp, pointed, curved, conical trichomes— Cannabis 9. Unicellular, stellate trichomes—Deutezia scabra(b) Multicellular unbranched trichornes1. Uniseriate, bicellular, conical—Datura2. Biseriate—Calendula officinalis3. Multiseriate—Male fern(c) Multicellular branched trichomes1. Stellate (star shaped)—Hamamelis, Kamala2. Peltate (shield-like structure)—cascarilla3. Candelebra (branched)—Rosemary, Verbascum thapsus4. T-shaped trichomes—Pyrethrum[B] Glandular trichomes (a) Unicellular glandular trichomes1. Sessile trichomes—Without stalk - Piper betel, Vasaka(b) Multicellular glandular trichomes1. Unicellular stalk with single spherical secreting cell at the apex—Digitalis purpurea2. Uniseriate, multicellular stalk with single spherical cell at the apex—Digitalis thapsi3. Uniseriate stalk and bicellular head—Digitalis purpurea4. Multicellular, uniseriate stalk and multicellular head—Hyoscyamus5. Biseriate stalk and biseriate secreting head—Santonica6. Short, unicellular stalk and head formed by a rosette of two to eight club-shaped cells—Mentha7. Multiseriate, multicellular cylindrical stalk and a secreting head of about eight radiating club-shaped cells—CannabisSenna Labelia Cannabis VasakaDigitalisNux vomicaStramomiumDaturaMale fern leafMarigoldMullein leaves(Verbascum thapsus)PyrethrumCascarilla barkTulsiKamala, HamamelisRosemaryFig. 4.4 Covering trichomesChapter-04.indd 33 10/12/2009 3:50:21 PM34 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYVasakaPeppermint, SageDigitalis,Digitalis lanataDigitalis,BelladonnaDaturaBelladonnaStramoniumMarigold, TabaccoPeppermint, Rosemary,Sage, SpearmintCapsicum calyxCannabisHyoscyamus,TobaccoFig. 4.5 Glandular trichomesPeridermIn the stem and root of mature plant, the layers immediately below the epidermis (phellogen) divide and redivide. On the outside they form cork or phellem and on the inner side they form phelloderm.Phellem + Phellogen + Phelloderm = PeridermEpidermisCorkPhellodermPeridermPhellogenFig. 4.6 PeridermThe cork cells are rectangular brick shaped or polygonal; phelloderm cells are mostly parenchymatous in nature. Len-ticels are present in the periderm, especially in the bark of old plants which are similar in function to stomata. These are open pores with absence of guard cells. The cork cells are impregnated with a layer of suberin. The various types of cork cells are shown bellow.Thick walled Thin walledflattenedThin walledpolygonalStratified corkFig. 4.7 Various types of cork cellsVascular Tissue SystemThis system consists of a number of vascular bundles which are distributed in the stele. The stele is the central cylinder of the stem and the root surrounded by the endodermis. It consists of vascular bundles, pericycle, pith and medullary rays. Each bundle is made up of xylem and phloem, with a cambium in dicotyledonous stems, or without a cambium in monocotyledonous stems, or only one kind of tissue xylem or phloem, as in roots. FunctionThe function of this system is to conduct water and raw food material from the roots to the leaves, and prepared food material from leaves to the storage organs and the growing regions.The vascular bundle of a dicotyledonous stem, when fully formed, consists of three well-defined tissues: 1. Xylem or wood 2. Phloem or bast, and 3. Cambium.[1] XYLEM Xylem or wood is a conducting tissue and is composed of elements of different kinds, viz. (a) tracheids, (b) vessels or tracheae, (c) wood fibres and (d) wood parenchyma. Xylem, as a whole, is meant to conduct water and mineral salts upwards from the root to the leaf to give mechanical strength to the plant body.(a) Tracheids: These are elongated, tube-like cells with hard, thick and lignified walls and large cell cavities. Their ends are tapering, either rounded or chisel-like and less frequently, pointed. They are dead, empty cells and their walls are provided with one or more rows of bordered pits. Tracheids may also be annular, spiral, scalariform or pitted (with simple pits). In transverse section, they are angular—either polygonal or rectangular. Tracheids (and not vessels) occur alone in the wood of ferns and gymnosperms, whereas in the wood of angiosperms, they are associated with the vessels. Their walls being lignified and hard, their function is conduction of water from the root to the leaf.(a) (b)Fig. 4.8 (a) Tracheids with bordered pits (b) Scalariform tracheidChapter-04.indd 34 10/12/2009 3:50:21 PM35MORPHOLOGY OF DIFFERENT PARTS OF MEDICINAL PLANT(b) Vessels or tracheae: Vessels are cylindrical, tube-like structures. They are formed from a row of cells placed end to end, from which the transverse partition walls break down. A vessel or trachea is, thus, a tube-like series of cells, very much like a series of water pipes forming a pipeline. Their walls are thickened in various ways, and vessels can be annular, spiral, scalariform, reticulate, or pitted, according to the mode of thickening. Associated with the vessels are often some tracheids. Vessels and tracheids form the main elements of the wood or xylem of the vascular bundle. They serve to conduct water and mineralsalts from the roots to the leaves. They are dead, thick-walled and ligni-fied, and as such, they also serve the mechanical function of strengthening the plant body.Annular Spiral Scalariform Reticulate Vesselswith simplepitsVesselswithborderedpitsFig. 4.9 Different kinds of vessels(c) Xylem (wood) fibres: Sclerenchymatous cells associ-ated with wood or xylem are known as wood fibres. They occur abundantly in woody dicotyledons and add to the mechanical strength of the xylem and of the plant body as a whole.(d) Xylem (wood) parenchyma: Parenchymatous cells are of frequent occurrence in the xylem, and are known as wood parenchyma. The cells are alive and generally thin walled. The wood parenchyma assists, directly or indirectly, in the conduction of water, upwards, through the vessels and the tracheids. It also serves to store food.[2] PHLOEM The phloem or bast is another conducting tissue, and is composed of the following elements: (a) sieve tubes, (b) Companion cells, (c) phloem parenchyma and (d) bast fibres (rarely). Phloem, as a whole, is meant to conduct prepared food materials from the leaf to the storage organs and growing regions.(a) Sieve tubes: Sieve tubes are slender, tube-like struc-tures, composed of elongated cells which are placed end to end. Their walls are thin and made of cellulose. The transverse partition walls are, however, perforated by a number of pores. The transverse wall then looks very much like a sieve, and is called the sieve plate. The sieve plate may sometimes be formed in the side (longitudinal) wall. In some cases, the sieve plate is not transverse (hori-zontal), but inclined obliquely, and then different areas of it become perforated. A sieve plate of this nature is called a compound plate. At the close of the growing season, the sieve plate is covered by a deposit of colourless, shining substance in the form of a pad, called the callus or callus pad. This consists of carbohydrate, called callose. In winter, the callus completely clogs the pores, but in spring, when the active season begins, it gets dissolved. In old sieve tubes, the callus forms a permanent deposit. The sieve tube contains no nucleus, but has a lining layer of cytoplasm, which is continuous through the pores. Sieve tubes are used for the longitudinal transmission of prepared food materials—proteins and carbohydrates—downward from the leaves to the storage organs, and later upward from the storage organs to the growing regions. A heavy deposit of food material is found on either side of the sieve plate with a narrow median portion.Sieve plateSieve tubeCompanion cellPhloemparenchymaFig. 4.10 A sieve tube in longitudinal section(b) Companion cells: Associated with each sieve lube and connected with it by pores is a thin-walled, elongated cell known as the companion cell. It is living and contains protoplasm and an elongated nucleus. The companion cell is present only in angiosperms (both dicotyledons and monocotyledons). It assists the sieve tube in the conduc-tion of food.(c) Phloem parenchyma: There are always some par-enchymatous cells forming a part of the phloem in all dicotyledons, gymnosperms and ferns. The cells are living, Chapter-04.indd 35 10/12/2009 3:50:21 PM36 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYand often cylindrical. They store up food material and help to conduct it. Phloem parenchyma is, however, absent in most monocotyledons.(d) Bast fibres: Sclerenchymatous cells occurring in the phloem or bast are known as bast fibres. These are gen-erally absent in the primary but occur frequently in the secondary phloem.[3] CAMBIUMThis is a thin strip of primary meristem lying between the xylem and phloem. It consists of one or a few layers of thin-walled and roughly rectangular cells. Although cambial cells look rectangular in transverse section, they are very elongated, often with oblique ends. They become flattened tangentially, i.e. at right angles to the radius of the stem.Types of Vascular BundlesAccording to the arrangement of xylem and phloem, the vascular bundles are of the following types:(A) Radial vascular bundle: When the xylem and phloem form separate bundles which lie on different radii, alternat-ing with each other, as in roots. The radial vascular bundle is the most primitive type of vascular bundles. Phloemylem(B) Conjoint vascular bundle: When the xylem and phloem combine into one bundle, it is called as conjoint vascular bundle. There are different types of conjoint vascular bundles.(1) Collateral: When the xylem and phloem lie together on the same radius, the xylem being internal and the phloem external is called collateral. When cambium is present in collateral as in all dicotyledonous stems, the bundle is said to be open collateral, and when the cambium is absent, it is said to be closed collateral, as in monocotyledonous stems.PhloemylemCambiumCollateral open Collateral closed(2) Bicollateral:PhloemCambiumylemCambiumPhloemWhen the both phloem and cambium occur twice in a collateral bundle—once on the outer side of the xylem and again on the inner side of it, is called as bicollateral. The sequence is outer phloem, outer cambium, xylem, inner cambium and inner phloem. Bicollateral bundles are characteristics of Cucurbitaceae. They are also often found in Solanaceae, Apocynaceae, Convolvulaceae, Myrtaceae, etc. A bicollateral bundle is always open.(C) Concentric vascular bundle: When one kind of vascular tissue (xylem or phloem) is surrounded by the other is called as concentric vascular bundle. Evidently, there are two types, according to whether one is central or the other one is so. When the phloem lies in the centre and is surrounded by xylem, as in some monocotyledonous, the concentric bundle is said to be amphivasal (leptocentric). When, on the other hand, the xylem lies in the centre and is surrounded by phloem, the concentric bundle is said to be amphicribral (Hadrocentric). A concentric bundle is always closed. ylemPhloemAmphicribral(Hadrocentric)Amphivasal(Leptocentric)PhloemylemGround Tissue SystemGround tissue system is represented by the cortex, hypo-dermis, pith, mesophyll and portion of midrib of leaves and comprises of the following tissues.Chapter-04.indd 36 10/12/2009 3:50:22 PM37MORPHOLOGY OF DIFFERENT PARTS OF MEDICINAL PLANT(a) ParenchymaThe parenchyma consists of a collection of cells which are more or less isodiametric, that is, equally expanded on all sides. Typical parenchymatous cells are oval, spherical or polygonal. Their walls are thin and made of cellulose. They are usually living. Parenchymatous tissue is of universal occurrence in all the soft parts of plants. Its main function is storage of food material. When paren-chymatous tissue contains chloroplasts, it is called chlor-enchyma. Its function is to manufacture food material. A special type of parenchyma develops in many aquatic plants and in the petiole of banana. The wall of each such cell grows out in several places, like rays radiat-ing from a star and is, therefore, stellate or star-like in general appearance. These cells leave a lot of air cavities between them, where air is stored up. Such a tissue is often called aerenchyma. (a) (b) (c)Fig. 4.11 (a) Parenchyma, (b) Chlorenchyma and (c) Aeren-chyma(b) CollenchymaThis tissue consists of somewhat elongated, parenchyma-tous cells with oblique, slightly rounded or tapering ends. The cells are much thickened at the corners against the intercellular spaces. They look circular, oval or polygonal in a transverse section of the stem. The thickening is due to a deposit of cellulose, hemicellulose and protopectin. Although thickened, the cells are never lignified. Simple pits can be found here and there in their walls. Their thickened walls have a high refractive index and, therefore, this tissue435–452Chapter 26 Plant Tissue Culture 437–452PART – I Miscellaneous 453–521Chapter 27 Ayurvedic Pharmacy 455–460Chapter 28 Marine Pharmacognosy 461–470Chapter 29 Nutraceuticals and Cosmeceuticals 471–483Chapter 30 Natural Pesticides 484–494Chapter 31 Poisonous Plants 495–506Chapter 32 Natural Allergens 507–509Chapter 33 Natural Colours and Dyes 510–515Chapter 34 Hallucinogenic Plants 516–521PART – J Traditional Drugs of India 523–554Chapter 35 Detail Study of Traditional Drugs of India 525–554Index 555Biological Index 572PART A INTRODUCTION TO PHARMACOGNOSY1.1. MEANING OF PHARMACOGNOSYPharmacognosy, known initially as materia medica, may be defined as the study of crude drugs obtained from plants, animals and mineral kingdom and their constituents. There is a historical misinformation about who created the term pharmacognosy. According to some sources, it was C. A. Seydler, a medical student at Halle, Germany, in 1815; he wrote his doctoral thesis titled Analectica Pharmacognostica. However, recent historical research has found an earlier usage of this term. The physician J. A. Schmidt (Vienna) used that one in his Lehrbuch der materia medica in 1811, to describe the study of medicinal plants and their properties. The word pharmacog-nosy is derived from two Latin words pharmakon, ‘a drug,’ and gignoso, ‘to acquire knowledge of ’. It means ‘knowledge or science of drugs’.Crude drugs are plants or animals, or their parts which after collec-tion are subjected only to drying or making them into transverse or lon-gitudinal slices or peeling them in some cases. Most of the crude drugs used in medicine are obtained from plants, and only a small number comes from animal and mineral kingdoms. Drugs obtained from plants consist of entire plants, whereas senna leaves and pods, nux vomica seeds, ginger rhizome and cinchona bark are parts of plants. Though in a few cases, as in lemon and orange peels and in colchicum corm, drugs are used in fresh condition, and most of the drugs are dried after collections. Crude drugs may also be obtained by simple physical processes like drying or extraction with water. Therefore, aloe is the dried juice of leaves of Aloe species, opium is the dried latex from poppy capsules and black catechu is the dried aqueous extract from the wood of Acacia catechu. Plant exudates such as gums, resins and balsams, volatile oils and fixed oils are also considered as crude drugs.Further drugs used by physicians and surgeons or phar-macists, directly or indirectly, like cotton, silk, jute and nylon in surgical dressing or kaolin; diatomite used in filtration of turbid liquid or gums; wax, gelatin, agar used as pharmaceutical auxiliaries of flavouring or sweetening agents or drugs used as vehicles or insecticides are used in pharmacognosy.Drugs obtained from animals are entire animals, as can-tharides; glandular products, like thyroid organ or extracts like liver extracts. Similarly, fish liver oils, musk, bees wax, certain hormones, enzymes and antitoxins are products obtained from animal sources. Drugs are organized or unorganized. Organized drugs are direct parts of plants and consist of cellular tissues. Unorganized drugs, even though prepared from plants are not the direct parts of plants and are prepared by some intermediary physical processes, such as incision, drying or extraction with water and do not contain cellular tissue. Thus aloe, opium, catechu, gums, resins and other plant exudates are unorganized drugs. Drugs from mineral sources are kaolin, chalk, diatomite and other bhasmas of Ayurveda.1.2. ORIGIN OF PHARMACOGNOSYViews on the beginning of life on planet Earth have forever remained controversial and an unending subject of debate. Nevertheless, we can say with certainty that the vegetable kingdom was already there when man made his appearance on Earth. As man began to acquire closure acquaintance with his environment, he began to know more about plants, as these were the only curative agents he had. As he pro-gressed and evolved, he was not only able to sort on as to J. A. SchmidtC. A. SeydlerHistory, Definition and Scope of PharmacognosyCHAPTER1Chapter-01.indd 3 10/12/2009 3:47:09 PM4 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYwhich plant served for eating and which did not, but he went beyond and began to associate curative characteristics with certain plants, classifying them as painkillers, febri-fuge, antiphlogistics, soporific and so on. This must have involved no doubt, a good deal of trial and error, and pos-sibly some deaths in the beginning also, but as it happened antidotes against poisons were also discovered. As we shall see later, drug substitutes were also forthcoming. All these states of affairs indicate that the origin of pharmacognosy, i.e. the study of natural curative agents points towards the accent of human beings on mother earth, and its historical account makes it clear that pharmacognosy in its totality is not the work of just one or two continental areas but the overall outcome of the steadfast work of many of the bygone civilizations like the Chinese, Egyptian, Indian, Persian, Babylonian, Assyrian and many more. Many of today’s wonderful modern drugs find their roots in the medicines developed by the tribal traditions in the various parts of the world.1.3. HISTORY OF PHARMACOGNOSYIn the early period, primitive man went in search of food and ate at random, plants or their parts like tubers, fruits, leaves, etc. As no harmful effects were observed he con-sidered them as edible materials and used them as food. If he observed other effects by their eating they were consid-ered inedible, and according to the actions he used them in treating symptoms or diseases. If it caused diarrhoea it was used as purgative, if vomitting it was used as memtic and if it was found poisonous and death was caused, he used it as arrow poison. The knowledge was empirical and was obtained by trial and error. He used drugs as such or as their infusions and decoctions. The results were passed on from one generation to the other, and new knowledge was added in the same way. Ancient ChinaChinese pharmacy, according to legend, stems from Shen Nung (about 2700 B.C.), emperor who sought out and investigated the medicinal value of several hundred herbs. He reputed to have tested many of them on himself, and to have written the first Pen T-Sao, or Native Herbal, recording 365 drugs. These were subdivided as follows: 120 emperor herbs of high, food grade quality which are non-toxic and can be taken in large quantities to maintain health over a long period of time, 120 minister herbs, some mildly toxic and some not, having stronger therapeutic action to heal diseases and finally 125 servant herbs that having specific action to treat disease and eliminate stagnation. Most of those in the last group, being toxic, are not intended to be used daily over a prolonged period of weeks and months. Shen Nung conceivably examined many herbs, barks and roots brought in from the fields, swamps and woods that are still recognized in pharmacy (podophyllum, rhubarb, gin seng, stramonium, cinnamon bark and ephedra).Inscriptions on oracle bones from the Shang Dynasty (1766–1122 B.C.), discovered in Honan Province, have pro-vided a record of illness, medicines and medical treatment. Furthermore, a number of medical treatises on silk banners and bamboo slips were excavated from the tomb number three at Ma-Huang-Tui in Changsha, Hunan Province. These were copied from books some time between the Chin and Han periods (300 B.C.–A.D. 3) and constitute the earliest medical treatises existing in China.The most important clinical manual of traditional Chinese medicine is the Shang Hang Lun (Treatise on the Treatment of Acute Diseases Caused by Cold) written by Chang Chung-Ching (142–220).in section is very conspicuous under the micro-scope. Collenchyma is found under the skin (epidermis) of herbaceous dicotyledons, e.g. sunflower, gourd, etc., occurring there in a few layers with special development at the ridges, as in gourd stem. It is absent from the root and the monocotyledon, except in special cases. The cells are living and often contain a few chloroplasts. Being flexible in nature, collenchyma gives tensile strength to the growing organs, and being extensible, it readily adapts itself to rapid elongation of the stem. Since it contains chloroplasts, it also manufactures sugar and starch. Its function is, therefore, both mechanical and vital.(a) (b)Fig. 4.12 (a) Collenchyma in transaction and (b) Collenchyma in longitudinal section(c) SclerenchymaSclerenchyma (scleros means hard) consists of very long, narrow, thick and lignified cells, usually pointed at both ends. They are fibre-like in appearance and hence, they are also called sclerenchymatous fibres, or simply fibres. Their walls often become so greatly thickened that the cell cavity is nearly obliterated. They have simple, often oblique, pits in their walls. The middle lamella is conspicuous in sclerenchyma. They are dead cells and serve a purely mechanical function, i.e. they give the requisite strength, rigidity, flexibility and elasticity to the plant body and thus enable it to withstand various strains. Sclereids: Sometimes, special types of sclerenchyma develop in various parts of the plant body to meet local mechanical needs. They are known as Sclereids or Stone cells. They may occur in the cortex, pith, phloem, hard seeds, nuts, stony fruits, and in the leaves and stems of many dicotyledons and also gymnosperms. The cells, though very thick-walled, hard and strongly lignified (sometimes cutinized or suberized), are not long and pointed like sclerenchyma, but are mostly isodiametric, polyhedral, short-cylindrical, slightly elongated, or irregular in shape. Usually, they have no definite shape. They are dead cells, and have very narrow cell cavities, which may be almost obliterated, owing to excessive thickness of the cell wall. They may be somewhat loosely arranged or closely packed. They may also occur singly. They contribute to the firm-ness and hardness of the part concerned.(a) (b)Fig. 4.13 (a) Sclerenchymatous fi bres and (b) Sclereids (Stone cells)Chapter-04.indd 37 10/12/2009 3:50:22 PM38 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRY4.4. CELL CONTENTSIn pharmacognosy, we are concerned with the cell contents which can be identified in plant drugs by microscopical and physical tests. These are either food storage products or the by-products of plant metabolism and include carbohy-drates, proteins, lipids, calcium oxalate, calcium carbonate, tannins, resins, etc. Some of these cell contents of diagnostic importance can be briefly described as follows.StarchStarch is present in different parts of the plant in the form of granules of varying size. Starch is found abundantly in fruit, seed, root, rhizome and as smaller grains in chloro-phyll containing tissue of the plant such as leaf. Starches of different origins can be identified by studying their size, shape and structure, as well as, position of the hilum and striations. Chemically, starches are polysaccharides contain-ing amylopectin and β-amylose. Starch turns blue to violet when treated with iodine solution.Starches of pharmaceutical interest are obtained from maize, rice, wheat and potato. These starches can be dif-ferentiated from each other by microscopical examination. A comparative account of their macroscopical, microscopical and physical characteristics is given in the Table 4.2. For purpose of microscopical studies, the powder should be mounted in Smiths starch reagent containing equal parts of glycerin, water and 50% acetic acid.Table 4.2 Characteristics of some starch grainsSl. No.Charac -teristicMaize Rice Wheat Potato1. Colour White White Faint grey Yellowish tint2. Shape Simple grains, angular, hilum central, rarely compound grainsSimple or compound grains (2–150 components), polyhedral with sharp anglesMostly simple (large and small) grains, faint striations, Hilum appears as lineFlattened ovoid or subspherical, well-marked striations, hilum eccentric.3. Size in μm5–30 2–10 Small 2–9 Large 10–4510–1004. pH Neutral Alkaline Acidic Acidic5. Moisture content (%v/w)13 13 13 206. Ash content (%w/w)0.3 0.6 0.3 0.3A systematic description of starch grains should include: 1. Shape—Ovoid, spherical, sub-spherical, ellipsoidal, polyhedral, etc. 2. Size—Dimensions in μm. 3. Position of hilum—Central, eccentric, pointed, radiate, linear, etc. 4. Aggregation—Simple, compound; number of compo-nents present in a compound grain. 5. Appearance between crossed polaroids. 6. Location—Loose, present in type of cell and tissue. 7. Frequency—Occasional, frequent, abundant.Patato starch Wheat starchRice starch Mai e starchFig. 4.14 Starch grains obtained from the different sourcesAleurone GrainProtein is stored in the form of aleurone grain by plants. Aleurone grain consists of a mass of protein surrounded by a thin membrane, and is found abundantly in the endosperm of the seed. The ground mass of protein, however, often encloses an angular body (crystalloid) arid one or more rounded bodies (globoids).Defat thin sections containing aleurone grains and treat with the following reagents. 1. Alcoholic picric acid—Ground tissue and crystalloid are stained yellow. 2. Millon’s reagent—Protein is stained red on warming. 3. Iodine solution—Only crystalloid and ground substance are stained yellowish brown.Calcium Oxalate CrystalsCalcium oxalate crystals are considered as excretory prod-ucts of plant metabolism. They occur in different forms Chapter-04.indd 38 10/12/2009 3:50:22 PM39MORPHOLOGY OF DIFFERENT PARTS OF MEDICINAL PLANTand provide valuable information for identification of crude drugs in entire and powdered forms. 1. Microsphenoidal or sandy crystals—Belladonna. 2. Single acicular crystals—Cinnamon, gentian, 3. Prismsmatic crystals—Quassia, hyoscyamus, senna, rau-wolfia, cascara. 4. Rosettes crystals—Stramonium, senna, cascara, rhubarb. 5. Bundles of acicular crystals—Squill, ipecacuanha.The sections to be examined for calcium oxalate should be cleared with caustic alkali or chloral hydrate. These reagents very slowly dissolve the crystals, so the observa-tion should be made immediately after clearing the section. The polarizing microscope is useful in the detection of small crystals.Mount the cleared section or powder in the following reagents and observe the crystals. 1. Acetic acid—Insoluble 2. Caustic alkali—Insoluble 3. Hydrochloric acid—Soluble 4. Sulphuric acid (60% w/w)—Soluble, on standing replaced by needles of calcium sulphate.Calcium CarbonateAggregates of crystals of calcium carbonate are called ‘cys-toliths’, which appear like small bunches of grapes in the tissue. Calcium carbonate dissolves with effervescence in acetic, hydrochloric or sulphuric acid. When treated with 60% w/w sulphuric acid, needled shaped crystals of calcium sulphate slowly separate out.Fixed Oils and FatsFixed oils and fats are widely distributed in both vegetative and reproductive parts of the plant. They are more con-centrated in the seeds as reserved lipids. Fixed oils occur as small refractive oil globules, usually present in association with aleurone grains. Fixed oil and fat show certain common characteristics and respond to the following tests: 1. They are generally soluble in ether and alcohol with few exceptions. 2. 1% solution of osmic acid colours them brown or black. 3. Dilute tincture of alkanna stains them red on standing for about 30 minutes. 4. A mixture of equal parts of strong solution of ammoniaand saturated solution of potash slowly saponifies fixed oil and fat.MucilageMucilages are polysaccharide complexes of sugar and uronic acids, usually formed from the cell wall. They are insoluble in alcohol but swell or dissolve in water. The following tests are useful for the detection of mucilage in cells. 1. Solution of ruthenium red stains the mucilage pink. Lead acetate solution is added to prevent undue swell-ing or solution of the substance being tested. 2. Solution of corallin soda and 25% sodium bicarbon-ate solution (alkaline solution of corallin) stain the mucilage pink.4.5. CELL DIVISIONFrom the smaller plants like algae to the large trees like eucalyptus, all starts their growth from a single cell called as egg cell. It is brought about by the development of new cells. Two important processes are continued which ultimately helps in the vegetative growth and also in the preservation of hereditary characteristics. It includes the division of nucleus termed as mitosis and the division of cell cytoplasm, referred to as cytokinesis.MitosisMitosis is a somatic cell division which is responsible for the development of vegetative body of the plants. A German Botanist Stransburger (1875) first studied it in detail. The process of mitotic cell division consists of four important stages, viz. prophase, metaphase, anaphase and telophase (Figure 4.15).ProphaseThis phase of chromosome fixation is the longest one in the mitotic cell division. Firstly, the indistinct chromosomes appear as the recognizable thread. Chromosomes are closely occurring double threads of which each longitudinal half becomes chromatid. Gradually chromosomes are thick-ened. Chromatid starts dividing longitudinally into two halves along with chromosomal substance matrix around it. Some gap start appearing in the chromosomes which is called as centromeres. At the end of prophase, nucleoli become smaller, matrix becomes clearer and the nucleus enters into metaphase. MetaphaseDuring this phase nuclear membrane vanishes and the spindle formation takes place; Bipolar spindle is made up of delicate fibres. Later the nuclear membrane is removed; spindle appears into the nuclear region. Movement of chromosomes to the equatorial plane of spindle separates them from one another. Centromeres are along the equators while the arms of the chromosomes are directed towards the cytoplasm where they are most clearly revealed.ProtometaphaseNucelear envelope fragments. Microtubes of spindle invade nuclear area and are able to interact with chromosomes. Chromosomes are more condensed. The two chromatids have kinetochore-protein structure. Microtubes attach to kinetochore and move the chromosomes back and forth. The kinetochore that do not attach interact with others from the opposite pole.Chapter-04.indd 39 10/12/2009 3:50:23 PM40 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYAnaphaseIn anaphase, chromatid halves move away equatorially at two opposite poles with the tractile fibres. The chromatid separates completely from each other. The spindle under-goes maximum elongation to facilitate separation of diploid chromatids. It is a shortest phase of mitosis.TelophaseIn telophase, chromatids forms the close groups. The polar caps of the spindle disappear and the formation of nuclear membrane takes place around the groups of chromosomes. The matrix and spindle body disappears completely. Appear-ance of nucleoli and nuclear sap makes them recognizable as two distinct nuclei.Once again nucleus formed grows in size and starts working as metabolic nuclei to enter again in the cycle of mitotic cell division. It mainly depends upon types of plants, plant part and temperature.CytokinesisCytokinesis is the partition of cytoplasmic material. It takes place either by formation of new cell walls or by cytoplasmic breakdown. New cells are formed by deposition of cellulosic material in the equatorial zones, which forms the membrane and divide cytoplasm into newly formed cells.MeiosisMeiosis is a process of nuclear division in which the numbers of chromosomes are reduced to half (n) from the basic nucleus of 2n chromosomes. A German botanist Stransburger (1888) was the first researcher of this complex genetic process. Chromosomes are called as the carriers of hereditary characters, so the meiosis is the process of transmission of these genetic characteristics. All sexually reproducing plants and animals are gametes with haploid number of chromosomes. Fusion of the male and female gametes results into zygote whereby doubling of chromo-somes to 2n takes place to develop offspring.Meiosis involves two successive divisions: the first process of division I is reduction division, while the second process of division II is similar to that of mitosis, (Figure 4.16).Division IIn this process of meiosis mother nucleus undergoes com-plicated changes which can be subdivided into various phases as given below.Fig. 4.15 Phases of mitotic cell divisionNucleusCentriolesNuclearenvelopeNuclear envelopbreaks downNucleusNucleolusChromatinDaughterchromosomesAsterProphaseTelophaseAnaphaseMetaphasePrometaphaseChromatidsof chromosome CentromereregionDevelopingspindleChapter-04.indd 40 10/12/2009 3:50:23 PM41MORPHOLOGY OF DIFFERENT PARTS OF MEDICINAL PLANTCentriolesNucleusNucleolusProphase Metaphasenterphase Telophase AnaphaseProphase Metaohase Anaphase Germ cellsFig. 4.16 Phases of meiosisProphase I: In this phase chromosomes are systematically arranged. This phase is again divided into five different stages:Leptotene: � This is an early prophase in which diploid chromosomes are found as long, single threads of iden-tical pairs. Coiling of these threads of chromosomes occurs.Zygotene: � Identical chromosomes gets attracted towards each other and the pairs are developed throughout their length. This pairing is termed as synapsis. The Chro-mosomes thus paired are homologous in nature. Pachytene: � The pairs of chromosomes go shorter and thicker due to coiling. Longitudinal splitting in it gives rise to four chromatids from each chromosome. This is a longer phase of prophase I.Diplotene: � This is a stage where separation of chromatids takes place. Their point of attachment remains at a single point known as chiasmata. At this stage the exchange of the genetic material occurs due to crossing over, a prominent feature of meiosis. With further thickening and shortening of chromosomes, diplotene ends into Diakinesis.Diakinesis: � In this last stage of prophase I, two halves of the chromosome starts moving equatorially. Chiasmata remain as a point of attachment. Nucleolus disappears and nuclear membrane gets dissolved to release the chromosomes in cytoplasm. Nuclear spindle formation begins at the end of diakinesis.Metaphase I: In this phase both the chromatids starts moving to two opposite poles of the spindle. In mitotic metaphase chromosomes are lined up at the opposite poles while in meiosis chiasmata remains attached to spindle fibres at the opposite poles.Anaphase I: The Chiasmata of the homologous chro-matids repels each other to opposite poles. Chromosomes are carried away by the tractile fibres to the equators. This is an important stage at which reduction of chromosome number from diploid to haploid occurs.Telophase I: At both the equatorial poles, pairs of chroma-tids start developing as the two haploid daughter nuclei. The nucleolus starts reappearing and the formation of nuclear membrane takes place. Two daughter nuclei thus formed enters in the second process of Division II.Division IIAll the phases of division II are similar to that of mitotic cell division. Telophase I passes into prophase II.Prophase II: Both the chromatid groups which have the loose ends go on coiling and become shorter and thicker. Nucleolus and nuclear membranevanishes and spindle fibres show its appearance. Metaphase II: In Metaphase II, chromatids once again starts separating equatorially at two opposite poles. Pairs of chromatids separate completely with its own centromere and ends in Anaphase II.Anaphase II: At the stage of Anaphase II, two sister chro-matids of each pair of chromosome move to opposite poles of the spindle as directed by the centromeres.Telophase II: In Telophase II, both the polar groups of chromosomes are converted to the nuclei by formation of nuclear membrane.Lastly via cytokinesis four daughter cells are formed each having the haploid or ‘n’ number of chromosomes.4.6. MORPHOLOGICAL STUDYThe abundance of plants and their size from bacteria to huge trees make it difficult to study their morphological characters. Classification of plants has solved the problem to a greater extent. Still it is impossible to define precisely the plant body as made up of certain parts only. Plants exhibit vividness in several respects.The details of morphological characters of these plant organs are as under.Morphology of BarkThe bark (in commerce) consists of external tissues lying outside the cambium, in stem or root of dicotyledonous plants. Following are the tissues present in bark:Cork (phellum), phellogen and phelloderm (collectively known as periderm), cortex, pericycle, primary phloem and secondary phloem. In Botany, the bark consists of periderm and tissues lying outside it, i.e. cork, phellogen and phelloderm.Chapter-04.indd 41 10/12/2009 3:50:23 PM42 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYMethods of collection of barksBark is generally collected in spring or early summer because the cambium is very active and thinwalled and gets detached easily. Following are the methods of col-lection of barks.1. Felling method: The fully grown tree is cut down near the ground level by an axe. The bark is removed by making suitable longitudinal and transverse cuts on the stem and branches. The disadvantages of this method are (a) the plant is fully destroyed and (b) the root bark is not utilized.2. Uprooting method: In this method, the stem of definite age and diameter are cut down, the root is dug up and bark is collected from roots, stems and branches. In Java, cinchona bark is collected by this method.3. Coppicing method: The plant is allowed to grow up to certain age and diameter. The stems are cut at a certain distance from ground level. Bark is collected from stem and branches. The stumps remaining in the ground are allowed to grow up to certain level; again the shoots are cut to collect the bark in the same manner. Cascara bark and Ceylon cinnamon bark are collected by this method.Morphology of barkThe following features may be used to describe the morphology of bark.1. Shape: The shape of the bark depends upon the mode of cuts made and the extent and shrinkage occurred during drying. (a) Flat: When the large piece of the bark is collected from old trunk and dried under pressure, the bark is flat, e.g. Quillaia and Aarjuna barks. (b) Curved: Here, both the sides of the bark are curved inside, e.g. Wild cherry, Cassia and Cascara barks. (c) Recurved: Both sides of bark are curved outside, e.g. Kurchi bark. (d) Channelled: When the sides of bark are curved towards innerside to form channel, e.g. Cascara, Cassia and Cinnamon barks. (e) Quill: If one edge of bark covers the other edge, it is called quill, e.g. Ceylon, Cinnamon and Cascara barks. (f) Double quill: Here, both the edges curve inward to form double quill, e.g. Cinnamon and Cassia barks. (g) Compound quill: When the quills of smaller diameter are packed into bigger quills, it is called compound quills. Compound quills are formed to save the space in packing and transportation, e.g. Cinnamon bark.(a) lat (b) uilt (c) Double uill(d) Channelled (e) Exfoliatedbark (g) Ridges andfurrows(f) Cracks andfissuresFig. 4.17 Morphological characters of bark2. Outer surface: (a) Smooth: When development of cork is even, e.g. Arjuna bark. (b) Lenticels: They are transversely elongated holes formed on outer surface because of lateral pressure, e.g. Wild Cherry and Cascara barks. (c) Cracks and fissures: They are formed due to increase in diameter, e.g. Cinchona bark (d) Longitudinal wrinkles: They are formed because of shrinkage of soft tissues, e.g. Cascara bark. (e) Furrows: If troughs between wrinkles are wide, it is called furrows, e.g. Cinchona calisaya bark. (f) Exfoliation: Sometimes the cork of bark flakes off exposing cortex, e.g. in Wild cherry bark. (g) Rhytidoma: It is composite dead tissue consisting of alternate layers of cork, cortex and/or phloem, e.g. Quillaia and Tomentosa barks. Sometimes it is removed during peeling. (h) Corky warts: They are the small circular patches, found sometimes in old barks, e.g. in Cinchona succirubra and Ashoka barks. (i) Epiphytes: Such as moss, lichen and liverwarts are sometimes seen in bark, e.g. Cascara bark.3. Inner surface: The colour and condition of inner surface is of diagnostic value. (a) Striations: When parallel longitudinal ridges are formed during drying, it is called striations; it may be fine or coarse, e.g. Cascara bark.Chapter-04.indd 42 10/12/2009 3:50:23 PM43MORPHOLOGY OF DIFFERENT PARTS OF MEDICINAL PLANT (b) Corrugations: They are the parallel transverse wrinkles formed due to longitudinal shrinkage, e.g. Cascara bark.4, Fracture: The appearance of exposed surface of trans-versely broken bark is called fracture. Different types of fracture, their descriptions and examples are given in Table 4.3.Table 4.3 Various types of fracture of barkSr. No. Type Description Examples of barks1. Short Smooth Cassia, Cinnamon, Cascara 2. Granular Shows grain-like minute prominences Wild cherry 3. Splintery Shows uneven projecting points Quillaia 4. Fibrous Shows thread-like fi bres Cascara 5. Laminated Shows tangentially elongated layers QuillaiaHistology of barksThe bark shows following microscopical character: (i) Tabular, radially arranged cork cells, may be suberised or lignified (e.g. in Cassia bark), (ii) Thin-walled cellulosic parenchymatous phellogen and phelloderm, (iii) Collenchy-matous and/or parenchymatous cortex, (iv) Parenchymatous or scleranchymatous pericycle; may contain band of stone cells and fibres, (v) Primary phloem which is generally crushed, e.g. in Cascara and Arjuna and (vi) Secondary phloem consisting of sieve tubes, companion cells, phloem parenchyma, phloem fibres and stone cells. Phloem fibres are thick walled, lignified, e.g. in Cinchona and Cascara; stone cells are thick, lignified with narrow lumen, e.g. Kurchi and Cinnamon barks; sometimes branched stone cells are seen in Wild cherry bark, (vii) Thin walled, living radially elon-gated medullary ray cells which are uni-, bi- or multiseriate and straight or wavy, (viii) Starch, calcium oxalate, oil cells, mucilage, etc., are often present in cortex.Morphology of RootsRoot is a downward growth of the plant into the soil. It is positively geotropic and hydrotropic. Radicle from the ger-minating seed grows further into the soil to form the root. It produces similar organs. Root does not have nodes or internodes. Branching of the root arises from the pericyclic tissues. Roots are covered by root caps or root heads.[A] Functions of roots 1. Roots fix the plant to the soil and give mechanical support to the plant body. 2. Roots absorb water and the minerals dissolved in it from the soil and transport them to the aerial parts where they are needed. 3. At times, the root undergoes modification and per-forms special functions like storage, respiration, repro-duction, etc.[B] Various parts of a rootA typical underground root exhibits the following parts:(a) Root cap: The tip of the root is very delicate and is covered by rootcap. Root cap protects the growing cells and as and when it is worn out it is replaced by the underlying tissues immediately.(b) Region of cell division: The next layer of tissue lying immediately after the root cap towards the stem is the meristematic tissue producing new cells, known as region of cell division or growing region.(c) Region of elongation: The newly formed cells in the growing region grow further by elongation in this region resulting in the increase in the length of the root.(d) Region of root hairs: Above the region of elonga-tion is the region of root hairs wherein the root hairs, the unicelluar, tubular outgrowths formed by the epiblema are formed. They are responsible for strengthening the hold of root into the soil and also for the absorption of water.(e) Region of maturation: It is located above the region of root hairs. It does not absorb anything, but is mainly responsible for the absorbed material by roots. The root branches or the lateral roots are produced in this region.Region of maturationRegion of root hairsRegion of elongationRegion of cell divisionRoot capFig. 4.18 Apex of root showing different regions[C] Types of rootsThere are two types of root systems: (a) Tap root system or primary roots and (b) Adventitious roots.(a) Tap root system: The radicle grows into the soil and forms main axis of the root known as tap Chapter-04.indd 43 10/12/2009 3:50:23 PM44 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYroot. It grows further to produce branches in the acropetal manner known as secondary roots which further branches to give tertiary roots. These are all true roots. This system is characteristic of dicotyledons.(b) Adventitious root system: The roots that develop from any part of the plant other than radicle are termed as adventitious roots. They may develop from root base nodes or internodes. This type of root system is found in monocots and in pterido-phytes.(a) (b)Fig. 4.19 (a) Tap root system and (b) Adventitious root systemI. Modification for storage of food: This type of modifi-cation is shown by both the types of roots, i.e. tap roots and adventitious roots. They store carbohydrates and are used during early growth of successive season. (i) Tap roots show the following three types of modifica-tions:(a) Conical: These are cone-like, broader at the base and tape-ring at the tip, e.g. carrot.(b) Fusiform: These roots are more or less spindle shaped, i.e. tapering at both the ends, e.g. radish.(c) Napiform: These are spherical shaped and very sharply tapering at lower part, e.g. beat and turnip.(a) (c)(b)Fig. 4.20 (a) Conical root, (b) Fusiform root and (c) Napiform root (ii) Adventitious root show the following types of modi-fications. They store carbohydrates but do not assume any special shape.(a) Tuberous roots: These get swollen and form single or isolated tuberous roots which are fusiform in shape, e.g. sweet potato, jalap, aconite.(b) Fasciculated tuberous roots: When several tuber-ous roots occur in a group or cluster at the base of a stem they are termed as fasciculated tuberous roots as in dahlia, asparagus.(c) Palmated tuberous roots: When they are exhibited like palm with fingers as incommon ground orchid.(d) Annulated roots: The swollen portion is in the form of a series of rings called annules as in ipecacuanha.II. Modifications for support: Plant develops special aerial roots to offer additional support to the plant by way of adventitious roots.(a) Clinging or Climbing roots: These types of roots are developed by plants like black pepper for support or for climbing purposes at nodes.(b) Stilt roots: This type of root is observed in maize and screw-pine, which grow vertically or obliquely downwards and penetrate into soil and give addi-tional support to the main plant.(c) Columnar roots: In certain plants like banyan, the additional support is given by specially developed pillars or columnar roots. They even perform the function of regular roots.(a) (b) (c)Fig. 4.21 (a) Climbing root (b) Stilt root (c) Columnar rootIII. Modifications for special functions:(a) Respiratory roots or pneumatophores: The roots of the plant growing in marshy places on sea-shores due to continuous water logging are unable to respire properly. They develop some roots growing against the gravitational force (in the air) with minute openings called lenticels. With the help of lenticels they carry on the exchange of gases. They look like conical spikes around the stems. This type of root is observed in case of plants called mangroves found in creeks, i.e. avicinnia.Chapter-04.indd 44 10/12/2009 3:50:23 PM45MORPHOLOGY OF DIFFERENT PARTS OF MEDICINAL PLANTFig. 4.22 Respiratory roots(b) Sucking roots or Haustoria: The plants, which are total parasites on the host, develop special type of roots for the purpose of absorption of food material from, the host. These roots neither possess root caps nor root hairs, and are known as sucking roots, e.g. cuscuta, striga and viscum.(c) Photosynthetic roots: Aerial roots in some cases, specially in leafless epiphytes become green in colour on exposure to sunlight and perform photosynthesis and are known as photosynthetic roots as in case of Tinospora cardifolia.(d) Epiphytic or Assimilatory roots: The plants which grow on the branches or stems of the plants without taking any food from them are called epiphytic and the roots developed by them are the epiphytic roots. They consist of the following:(i) Clinging roots with which they get fixed with the host and(ii) Aerial roots which hang freely in the air, which are normally long greenish white in colour and absorb moisture from the atmo-sphere with the help of porous tissue. These roots are devoid of root caps and root hairs. They carry on photosynthesis. These are developed in the plants growing in humid atmosphere. Bulbophyllum, uanda are the examples of this type.(e) Nodulated roots or root tubercles: The plants belonging to leguminosae family develop nodules or tubercles. These are formed by nitrogen fixing bacteria and getting carbohydrates from the plants. Roots and bacteria are symbiotic to each other. These swellings developed by roots are nodulated roots.Uses of roots 1. Source of food and vegetables: Most of vegetables constitute roots only, i.e. radish, turnip, beet, carrot, etc. They are rich sources of vitamins or their precur-sors. Some of them like sweet potato and tapioca are rich in starch, and hence are consumed as food. 2. Various types of medicinally important drugs are obtained from roots. Morphology of StemsThe plumule develops to form the stem. Thus stem is an aerial part of the plant. It consists of axis and the leaves. Stem has got the following characteristics: 1. It is ascending axis of the plant and phototropic in nature. 2. It consists of nodes, internodes and buds. 3. It gives rise to branches, leaves and flowers. 4. Stems may be aerial, sub-aerial and underground.Depending upon the presence of mechanical tissues, the stems may be weak, herbaceous or woody.[A] Weak stems: When the stems are thin and long, they are unable to stand erect, and hence may be one of the following types:(a) Creepers or Prostate stem: When they grow flat on the ground with or without roots, e.g. grasses, gokharu, etc.(b) Climbers: These are too weak to stand alone. They climb on the support with the help of ten-drils, hooks, prickles or roots, e.g. Piper betel, Piper longum.(c) Twinners: These coil the support and grow further. They are thin and wiry, i.e. ipomoea.[B] Herbaceous and woody stems: These are the normal stems and may be soft or hard and woody, i.e. sunflower, sugarcane, mango, etc. 1. Produce leaves and exposes them properly to sunlight for carrying out photosynthesis. 2. Conducts water and minerals from roots to leaves andbuds. 3. Foods produced by leaves are transported to nongreen parts of the plant. 4. Produce flowers and fruits for pollination and seal dispersal. 5. Depending upon the environment it gets suitably modified to perform special functions like storage of foods, means of propagation, etc.I. Underground modifications of stemsUnderground modifications of stems are of the following types: 1. Rhizome 2. Tuber 3. Bulb 4. Corm.1. Rhizomes: Grow horizontal under the soil. They are thick and are characterized by the presence of nodes, internodes and scale leaves. They also possess bud in the axil of the scale leaves, e.g. ginger, turmeric, rhubarb, male fern, etc.2. Tubers: Tubers are characterized by the presence of ‘eyes’ from the vegetative buds which grow further and develop into a new plant. Tubers are the swollen underground structure of the plant, e.g. potato, jalap, aconite, etc.Chapter-04.indd 45 10/12/2009 3:50:24 PM46 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRY3. Bulb: In this case, the food material is stored in fleshy scales that overlap the stem. They are present in the axils of the scales, and few of them develop into new plant in the spring season at the expense of stored food material in the bulb. Adventitious roots are present at the base of the bulb. The reserve food material formed by the leaves is stored at their bases, and the new bulbs are produced next year, e.g. garlic, squill and onion.(a) (b)Fig. 4.23 Bulbs (a) Onion (b) Garlic4. Corm: Corms are generally stout, and grow in vertical direction. They bear bud in the axil of the scaly leaves, and these buds then develop further to form the new plant. Adventitious roots are present at the base of the corm, e.g. saffron, colchicum, dioscorea, etc.II. Sub-aerial modifications of stems:These include (1) Runner, (2) Stolon, (3) Offset and (4) Sucker.1. Runner: These creep on the ground and root at the nodes. Axillary buds are also present, e.g. strawberry, pen-nywort.Fig. 4.24 Strawberry runner2. Stolon: These are lateral branches arising from the base of the stems which grow horizontally. They are character-ized by the presence of nodes and internodes. Few branches growing above the ground develop into a new plant, e.g. glycyrrhiza, arroroot, jasmine, etc.3. Offsets: These originate from the axil of the leaf as short, thick horizontal branches and also characterized by the presence of rosette type leaves and a cluster of roots at their bottom, e.g. aloe, valerian.4. Sucker: These are lateral branches developed from underground stems. Suckers grow obliquely upwards, give rise to a shoot which develop further into a new plant, e.g. mentha species, chrysanthemum, pineapple, banana, etc.Fig. 4.25 Sucker of menthaIII. Aerial modification of stemsAs the name indicates they grow into the air above the soil to a certain height, as follows:1. Phylloclades: At times, the stem becomes green and performs the function of leaves. Normally this is found in the plants growing in the desert (xerophytes). Phylloclades are characterized by the presence of small leaves or pointed spines, e.g. opuntia, ruscus, euphorbia, etc.Cladode is a type of phylloclade with one internode, i.e. asparagus.2. Thorns and prickles: This is another type of aerial mod-ification meant for protection. Thorns are hard, pointed, straight structures, such as duranta, lemon, etc. Prickles and thorns are identical in function. Prickles get originated from outer tissues of the stem. Thus, they are superficial outgrowths. Prickles are sharp, pointed and curved struc-tures. They are scattered all over the stem. Rose, smilax can be quoted as examples of the same.(a) (b)Fig. 4.26 (a) Thorns of duranta (b) Rose prickles3. Stem tendrils: In certain plants, the buds develop into tendrils for the purpose of support. Terminal buds in case of vitis, axillary bud in case of passiflora are suitable examples.4. Bulbils: These are modifications of floral buds meant for vegetative propagation, such as Dioscorea and Agave.Chapter-04.indd 46 10/12/2009 3:50:24 PM47MORPHOLOGY OF DIFFERENT PARTS OF MEDICINAL PLANTFig. 4.27 Bulbil of DioscoreaUses of stemsDepending upon the structural and chemical contents, stems are used for various purposes. 1. Underground stems in their various forms are either used as food spices or for culinary purposes like, potato, amorphophalus, colocasia, garlic, ginger and onion. 2. Jowar, rice and other stems are used as fodder. 3. Stems of jute, hemp and flax as sources of industrial fibres used for various purposes. 4. Sugarcane stems are used as source of sucrose while latex from stems of Hevea brasiliensis is used as rubber. 5. Woods from stems of several plants are used as drugs like quassia, guaicum, sandalwood, etc. 6. The stems of several plants are injured to produce gums for their multiple industrial uses like gum-acacia, gum-tragacanth, gum-sturculia, etc.Morphology of LeavesLeaves are flat, thin green, appendages to the stem, contain-ing supporting and conducting strands in their structure. They develop in such a way that older leaves are placed at the base while the younger ones at the apex.[A] A typical angiospermic leaf consists of the following parts:(a) Leaf base or hypopodium: By means of which it is attached to the stem.(b) Petiole: It is the stalk of leaf with which leaf blade is attached to the stem. It is also known as mesopodium. It may be present in leaf or may be absent in leaf. Leaves with petiole are called petiolate, and those without petiole sessile. They may be short or long and cylindrical. Sometimes, it is flattened as in the case of lemon. Then it is described as winged petiole. In some plants the petiole undergoes modification to form the tendrillar petiole which helps the plant to climb, e.g. clematis. In few aquatic plants it enlarges to form the swollen petiole by enclosing air and thus keep the entire plant floating over the water. In few other cases, the petiole enlarges to such an extent to form the leaf like structure as in Australian acacia and is known asphyllode.(c) Lamina or Leaf blade: The flat expanded part of the leaf is lamina or leaf blade (Epipodium). Lamina may be thick as in xerophytic leaves or thin as in hydrophytes or intermediate as in mesophytes.(d) Stipules: These are the two small outgrowths found at the base of the leaf, to protect the axillary bud. Leaves may or may not have stipules. Leaves with stipules are described as stipulate, while those without stipules are described as ex-stipulate.Some stipules perform special functions and hence are put into following types:1. Tendrillar stipules: The stipules get modified into coiled, tendrils helping the plant to climb, i.e. Indian sarsaparilla (Smilax microphylla).2. Foliaceous stipules: In case of plants with compound leaves some of the leaflets get converted into tendril and the stipules expand to form the flat surface and carry on photosynthesis, i.e. Lathyrus or pisum.3. Bud stipules: Scaly stipules of the Ficus sp. are charac-teristic, which protect the terminal vegetative bud. With the development and unfolding of the leaf the bud stipule falls off.4. Spiny stipules: In some plants, the stipules get converted into spines and help against browsing animals as in the case of Acacia and Zizyphus.There are five types of stipules which are as under:1. Free lateral: These are free and located on either side of the leaf as in China rose.2. Adnate: When the stipules unite with the petioles forming wing like structure are known as adnate stipules, i.e. Groundnut, rose, etc.3. Inter-petiolar: When stipules are located in between the two petioles of two leaves as in ixora.4. Axillary: When two stipules unite becoming axillary to the leaves.5. Ochreate stipules: These form a hollow tube around the stem as in Polygonum.(a) (b) (c)Fig. 4.28 (a) Free lateral stipules(b) Adnate stipules (c) Inter petiolar stipulesChapter-04.indd 47 10/12/2009 3:50:24 PM48 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYBefore considering the further anatomical details of the leaves, it is very essential to know the basic difference botanically between the leaf and the leaflet which is as under:Sr. No. Leaf Leafl et1. Bud or branch is present in the axil.Bud is absent.2. Leaves are solitary and are arranged spirallyThese are arranged in pairs3. These lie in different planes Leafl ets lie in the same plane4. Symmetrical at the bases, i.e. Belladonna, vasaka, eucalyptus, etc.Asymmetrical at bases, i.e. Rose, senna, acacia, etc.[B] Shape of the lamina of leavesVarious shapes of the leaves are due to various types or shapes of lamina. It may be one of the following: 1. Acicular: Needlelike, i.e. pinus. 2. Subulate: With acute apex and recurved point, i.e. Ephedra sinica. 3. Linear: When it is long, narrow and flat, i.e. Grasses. 4. Oblong: Broad leaves with two parallel margins and abruptly tapering apex, i.e. Banana. 5. Lanceolate: Which look like lance or spear shaped, e.g. nerium, senna. 6. Ovate: Egg shaped or broad base and narrow apex, e.g. China rose, Buchu. 7. Obovate: Broad apex and narrow base, e.g. Jangali-badam. 8. Obcordate: Inversely heart shaped, i.e. base is narrow but apex is broad, e.g. Oxalis. 9. Spathulate: Like spatula or spoon shaped as in calen-dula and drosera. 10. Cuneate: Wedge shaped as in pista. 11. Cordate: Heart shaped, i.e. betel. 12. Sagittate: Arrow shaped such as in arum. 13. Hastate: When the two lobes of sagittate leaf are directed outwards as in ipomoea. 14. Reniform: Kidney shaped, i.e. Indian pennywort. 15. Auriculate: When the leaf has got ear like projections at the base. 16. Lyrate: When it is lyre shaped or the blade is divided into lobes with large marginal lobe, i.e. radish mustard. 17. Runcinate: With the lobes convex before and straight behind, pointing backward like the teeth of the double saw, i.e. dendelion leaf. 18. Rotund (Orbicular): When the blade is circular or round, e.g. lotus. 19. Elliptical or oval: When the leaves are narrow at the base and apex but broad in themiddle such as guava, vinca, etc. 20. Peltate: When the lamina is shield shaped and fixed to the stalk by the centre.Fig. 4.29 Shape of the lamina of leaves[C] Leaf marginsLeaf margin may be of the following types: 1. Entire: When it is even and smooths, i.e. senna, eucalyptus. 2. Sinuate or wavy: With slight undulations like Ashok. 3. Crenate: When the teeth are round as in digitalis. 4. Dentate: Toothed margin, teeth directing outwards such as margosa, melon. 5. Serrate: When it is like the teeth of the saw such as rose, China rose, etc. 6. Ciliated: It is fringed with hairs. 7. Biserrate: Lobed serrate margin. 8. Bicrenate: Lobed crenate margin.Entire Sinulate Crenate Denatate Serrate Ciliate Bi serrate Bi crenateFig. 4.30 Margins of leavesChapter-04.indd 48 10/12/2009 3:50:25 PM49MORPHOLOGY OF DIFFERENT PARTS OF MEDICINAL PLANT[D] Leaf apicesThe apex of the leaf may be one of the following kinds: 1. Obtuse: Rounded tip, i.e. banyan. 2. Acute: When it is pointed to form acute angle, but not stiff, i.e. hibiscus. 3. Acuminate: Pointed tip with much elongation, peepal. 4. Recurved: When the apex is curved backward. 5. Cuspidate: With spiny tip like date palm. 6. Mucronate: Rounded apex ending abruptly in a short point i.e vinca, ixora. 7. Retuse: Broad tip with slight notch, i.e. pistia. 8. Emarginate: When tip is deeply notched as in bam-binia. 9. Tendrillar: Tip forming a tendril such as Gloriosa—superba.btuse Acute Acuminate RecurvedCuspidate Mucronate Retuse Emarginate TendrillaFig. 4.31 Leaf apices[E] Leaf basesThe lower extremity of the lamina of the leaf may exhibit one of the following shapes:(a) Symmetrical: Equal as in vasaka.(b) Asymmetrical: Unequal as in senna or datura.(c) Decurrent: As in digitalis.(d) Cordate: As in betel.Symmetrical Asymmetrical Decurrent CordateFig. 4.32 Leaf bases[F] Leaf surfaceIt may be of the following types:(a) Glabrous: When surface is smooth and free of hair or any outgrowth, i.e. vasaka, datura.(b) Rough: When harsh to touch, digitalis.(c) Hairy: When covered with hairs.(d) Glutinous: When covered with sticky substance, tobacco.(e) Glaucous: When covered with waxy coating, castor.(f) Pubescent: Covered with straight, short hair, i.e. senna.[G] Types of leavesTaking into consideration the nature of the lamina of the leaves, they are classified into two main groups: 1. Simple leaves and 2. Compound leaves.1. Simple leaves: A leaf which has only one leaf blade or lamina is called a simple leaf. It may be stipulate or exstipulate, petiolate or sessile, but always possess axillary bud in its axil. It may have an undivided lamina or may be lobed, e.g. vasaka, digitalis, eucalyptus, datura, carica, castor and argemone.2. Compound leaves: A compound leaf consists of more than one leaf blade or the lamina, the compound leaf is divided into several segments called leaflets or pinnae, e.g. senna, tamarind, acacia.Compound leaves have been further classified as (a) pinnate compound leaves and (b) palmate compound leaves.(a) Pinnate compound leaves: These are sub-classified as under depending upon the number of rachis (an axis bearing the leaflets in pinnate compound leaf is known as rachis):1. Unipinnate compound leaves: Wherein only one rachis bearing the leaflets is present. When an even number of leaflet is present, it is known as paripinnate, e.g. tamarind, gul mohor; if the number of leaflet is odd, it is described as imparipinnate, e.g. rose, margosa, etc.2. Bipinnate compound leaves: It consists of primary rachis and secondary rachis. The secondary rachis only bears the leaflets, e.g. acacia.3. Tripinnate compound leaves: These contain primary, secondary and even tertiary rachis. Tertiary rachii only bear the leaflets as in moringa, oroxylon.4. Decompound leaf: Wherein compound leaf is much divided irregularly as in coriander, carrot, anise, etc.Paripinnate mparipinnate Bi pinnate Tri pinnateFig. 4.33 Pinnate compound leaves(b) Palmate compound leaves: In this type the leaflets are born by the petiole of the leaf.Chapter-04.indd 49 10/12/2009 3:50:25 PM50 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYDepending upon the number of leaflets in a compound palmate leaf they are further divided as:(1) Unifoliate compound leaf: Lemon. (2) Trifoliate compound leaf: Bael, wood apple. (3) Multifoliate compound leaf: Bombax, alstonia.nifoliate Trifoliate MultifoliateFig. 4.34 Palmately compound leaves[H] VenationThe arrangement of veins in the lamina or leaf blade is known as venation. Veins are nothing but vascular bundles. Water and minerals absorbed by roots is conveyed to various parts of leaf by veins and the food synthesized by leaf by way of photosynthesis is translocated to other parts of plant through veins only. Veins also offer strength, support and shape to the lamina of the leaf. The prominent vein in the centre of the leaf is known as midrib. In the flower-ing plants two types of venations exist: (1) Reticulate and (2) Parallel.1. Reticulate venation: This type of venation is character-ized by the fact that many veins and veinlets in the lamina of the leaf are arranged in the form of network or reticulars. This type of venation is characteristic to dicotyledonous leaves. It is further sub-classified as:(a) Unicostate-reticulate venation: Where the leaf contains only one midrib and several veins are given out on both the sides to form the network such as henna, eucalyptus, peepal, etc.(b) Multicostate-reticulate venation: In this type many veins of equal strength arise from the end of the petiole. Each vein further branches to give rise to veinletsthat form the network. The veins may be convergent (meeting at the apex) or divergent (diverge towards the margin) as in castor, carica and cucurbita.nicostatereticulateMulticostate reticulate(convergent)Multicostate reticulate(divergent)Fig. 4.35 Reticulate venation2. Parallel venation: In this type the vein and veinlets in leaf blade are arranged parallel to one another. It is char-acteristic to monocotyledonous plants with few exceptions like dioscorea and sarsaparilla.Like reticulate venation, it may also be unicostate parallel venation or multicostate parallel venation as under:(a) Unicostate parallel venation: Wherein the leaf consists of only one midrib running from apex to the petiole of the leaf. The veinlets and veins arise parallel to one another on each side as in banana and canna.(b) Multicostate parallel venation: In case of multicostate parallel venation many number of main veins of equal strength arise from the tip or the petiole and run parallel to each other. It may be convergent as in case of several grasses and bamboo or divergent as in case of fan palm.nicostateparallelMulticostate parallel(Convergent)MulticostateparallelFig. 4.36 Parallel venation[I] PhyllotaxyIt is the mode of arrangement of leaves on the stem. Since the leaves are the chief organs of photosynthesis they must be exposed to sunlight favourably. This is done by arranging the leaves in systematic manner. Following are the various types of phyllotaxy: 1. Alternate or spiral: This phyllotaxy is characterized by the presence of one leaf at each node and all leaves together make a spiral path on the axis, i.e. tobacco, mustard and sunflower. 2. Opposite: When two leaves are placed at the same node and are opposite to one another. This is farther divided into two:(a) Opposite decussate: In this type a pair of leaves of one node is at right angles to the pair of leaves at the next node such as maddar, sacred basil, vinca.(b) Opposite superposed: When one pair of leaves is placed above the other exactly in the same plane, i.e. Rangoon creeper, ixora. 3. Whorled: When more than two leaves are present in a single node and are arranged in a circle as in nerium, alstonia. 4. Leaf mosaic: In this type, the leaves are so arranged that there will not be any overshading and all the Chapter-04.indd 50 10/12/2009 3:50:25 PM51MORPHOLOGY OF DIFFERENT PARTS OF MEDICINAL PLANTleaves are exposed properly. The older leaves have longer petiole while younger leaves have short petiole and are placed in the space left by the older leaves. It recalls the arrangement of glass bits in a mosaic and hence the name, e.g. Oxalis and acalypha.Whirled Leaf mosaicAlternate ppositedecussateppositesuperposedFig. 4.37 Types of phyllotaxy[J] Modifications of LeavesUnder the functions of leaves, it is stated that leaves have to perform two types of functions, i.e. primary functions and secondary functions. Under the primary function, leaves are known to perform three main functions like photosynthesis, gaseous exchange and transpiration. The secondary functions which the leaf has to perform are support, protection, storage of food material etc.To perform these secondary functions the leaf under-goes structural and physiological changes called modifica-tions. There are at least five types of leaf modifications known.1. Leaf tendrils: Leaves get modified into slender, coiled and wiry structures as seen in Lathyrus peas and gloriosa for support to the plant.2. Leaf spines: For the sake of protection certain leaves get converted into spines as seen in Aloe, argemone, acacia, etc.3. Phyllode: Petiole gets modified to flat leaf-like phyl-lode to reduce the transpiration, e.g. Australian acacia.4. Scale Leaves: In ginger and potato they protect the terminal buds, while in onion and garlic they store food material.5. Pitcher and bladder: These are specially developed modifications of leaves to capture and digest insects in case of carnivorous plants, e.g. Utricularis Bladder wort and Nepenthes.Leaf tendrils Pitcher plantFig. 4.38 Leaf modifi cationsMorphology of FlowersThe flower is actually a modified shoot meant for produc-tion of seeds. It consists of four different circles (whorls) arranged in a definite manner. A flower is built up on stem or pedicel with the enlarged end known as thalamus or receptacle. The four whorls of the flowers can be described as under:1. Calyx: It is the outermost whorl of flower and is gen-erally green in colour, the individual member of which is called sepal.2. Corolla: It is the second whorl of flower and is either white or bright coloured, each member of which is known as petal.3. Androecium: It is the third circle of flower and con-stitutes the male part. The individual component is called stamen and each stamen consists of filament, anther and connective.4. Gynoecium: This is the fourth circle of the flower and constitutes the female part. Each component is known as carpel or pistil and is made of stigma, style and ovary.StigmaStyleAntherConnectivePetalilamentvulevarySepalThalamusPedicelBractFig. 4.39 Typical parts of fl owerWhen all the four whorls, are present in a single flower, it is described to be a complete flower, absence of any one of them describes it as incomplete flower. A flower is described to be hermaphrodite or bisexual when it contains stamens and carpels. Absence of any one of them describes it as unisexual flower. When calyx and corolla in a flower Chapter-04.indd 51 10/12/2009 3:50:25 PM52 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYare similar in colour and shape, then both of them (calyx and corolla) together are called Perianth, i.e. garlic, onion, asperagus.When a flower is divided into two equal parts by any ver-tical section passing through the centre, then it is described as regular or symmetrical or actinomorphic flower as in ipomoea, rose, datura and shoe flower. But when it cannot be divided equally into two parts by one vertical section, then it is described as irregular or asymmetrical or zygo-morphic flower.When the stamens arise from petals instead of thalamus, the petals are called epipetalous. When the stamens get united with gynaecium the structure is known as gynaste-mium. The union of stamens among themselves is known as cohesion. When the filaments of stamen get united to form a single bundle, it is known as monoadelphous. When it forms two bundles, it is known as diadelphous. When anthers get united to form a column (but filaments are free), the stamens are known as syngenesious. When ovary consists of only one carpel, it is said to be monocarpellary and when it contains more than one carpel, it is said to be polycarpellary. When the carpels in ovary are free, the ovary is described as apocarpous and when they are united it is known as syncarpous.(a) (b)Fig. 4.40 (a) Actinomorphic fl ower (b) Zygomorphic fl owerArrangement of Floral Parts on ThalamusDepending upon the arrangement of floral parts on thala-mus, the flowers may be of three types.(i) Hypogynous flower (Superior ovary): Herein the thalamus is conical, flat, convex and stamens, sepals and petals are arranged at base and ovary at the apex, e.g.: brinjal, china rose, mustard, etc.(ii) Perigynous flowers (Half-superior Ovary): Thala-mus is flat, sepals and stamens grow around the ovary. The flowers are said to be perigynous as in Rose, Strawberry peach.(iii) Epigynous flower (Inferior ovary): The thalamus is fused with ovary wall, calyx, corolla, stamen appear at the top and the gynaecium at the bottom as in Sunflower, cucumber, apple, etc.(a) (b) (c)Fig. 4.41 (a) Superior ovary (b) Half-superior ovary (c) Inferior ovaryPlacentationThe type of distribution of placentae in the ovary is called placentation. They are of the following types.1. Marginal: It is characteristic tomonocarpellary ovary and placentae arise on ventral suture, e.g. bean and pea.2. Axil: It is characteristic to polycarpellary syncarpous, bilocular or multilocular ovary. Ventral sutures of each carpel meet at the centre and each of them have marginal placentation, e.g. onion, china rose, ipomoea.3. Parietal: It is characteristic to polycarpellary syncarpous ovary and the placentae develop on the ventral suture but the ovary is unilocular as in papaya and cucurbita.4. Free Central: It is characteristic to polycarpellary syn-carpous ovary, which is unilocular. Ovules arise on the central axis, but it is not connected with the peripheral wall, e.g. Dianthus, saponaria, portulacca.5. Basal: It is characteristic to polycarpellary and unilocular ovary. Only one ovule is present and it arises from its base as in sunflower.Marginal Axile Parietal ree central BasalFig. 4.42 Types of placentationPollinationPollination is the process of transference of pollen grains from the anther of a flower to the stigma of the same flower or another flower of the same or allied species. Pollen grains are produced by bursting the anther and are carried by various agencies to the stigma.The agencies may be insects of various types, wind or even water. There are two types of pollination, i.e. (a) Self-pollination or autogamy and (b) cross pollination or allogamy.Chapter-04.indd 52 10/12/2009 3:50:25 PM53MORPHOLOGY OF DIFFERENT PARTS OF MEDICINAL PLANT (a) Self-pollination: There are two types of self-pollina-tion, i.e.Homogaxny: � In this case the anthers and stigmas of a flower mature at the same time.Clestogamy: � It is found in flowers which never open or in the underground flowers of Commeline bengalensis. (b) Cross-pollination: Pollination through the agency of insects, animals (such as snails, bats, squirrels, birds and even human being) wind and water is cross-pollinationPollination by insects is known as entomophily. To attract various insects, plants adapt different means such as colour, nectar and scent. Entomophilous pollination is very common in plants.Morphology of InflorescencePlant bear flowers either solitary or in groups. The flowers which are large and showy are normally borne solitary, but which are not so prominent and are small, occur in group or bunches.The form of natural bunch of flowers in which they occur is called inflorescence. Depending upon the type of branching various forms of inflorescences are known. The axis on which the flowers are arranged is known as peduncle while the stalks of flowers are known as pedicels. Types of InflorescencesFollowing are the types of inflorescences:(A) Racemose or indefinite inflorescence:1. Raceme: In this type of inflorescence the peduncle is long. Flowers are stalked and born in acropetal succession and peduncle has indefinite growth and goes on produc-ing flowers as in mustard, radish, dwarf gold mohor, etc. When the main axis is branched and the lateral branches bear the flowers, it is said to be Compound raceme or panicle or branched raceme as in gul mohor, peltopho-rum, yuchr, etc.2. Spike: This is similar to raceme, with sessile flowers as in Rangoon creeper, vasaka. A branched spike of poly-anthes and terminalia species is known.3. Spadix: In this inflorescence the peduncle is short with numerous small unisexual flowers, which are sessile and covered with boat shaped bract known as Spathe, i.e. banana, arum, palms and coconut are the example of compound spadix.4. Catkin: A spike with unisexual sessile flowers on long peduncle as in mulberry and oak.5. Umbel: Axis is shortened and bears flowers at its top which are having equal stalk and arranged in centripetal succession. A whorl of bracts is present at the base of inflo-rescence as in coriander, caraway, cumin, fennel, etc.Raceme Spike SpadixFig. 4.43 Types of infl orescence6. Spikelet: It is present in family Graminae characterized by small and branched spikes. Spikelets are provided with two bracts at the base known as glumes, and bracteole called palea.7. Corymb: Peduncle is short, flowers bracteate, bisexual oldest flower is lower most and youngest at apex. Lower-most has longest stack and youngest has shortest, lying at same level.8. Capitulum or Head: In this type flattened and expanded peduncle is present, called as receptacle. Base of receptacle is covered with bracts. The flowers are small and sessile (florets). Flowers towards the periphery are older, while at the centre, they are younger and open later. Two types of flowers are present, i.e. ray florets (strap shaped) and disc florets (tubular shaped), e.g. zinnia, cosmos, sunflower.9. Capitate: Inflorescence similar to umbel type, except the flowers are sessile, i.e. acacia.(B) Cymose inflorescence: In this type the growth of the main axis or peduncle is stopped by producing the flower. The order of opening is centrifugal. Its types are as under:1. Solitary cyme: In this type the inflorescence ends in a single flower as in datura, capsicum, China rose, etc.2. Uniparous or monochasial cyme: In this type, axis ends in a flower only; one branch arises just behind and ends in a flower. Uniparous depending upon the type of branching is again subdivided into (a) Hellicoid uniparous and (b) Scorpioid uniparous. Hellicoid uniparous is characterized by branching on one side only, while scorpoid uniparous cyme by branch-ing on alternate side.(a) (b) (c)Fig. 4.44 (a) Uniparous helicoids cyme, (b) Uniparous scorpoid cyme (c) Biparous cymeChapter-04.indd 53 10/12/2009 3:50:25 PM54 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRY3. Biparous or Dichasial cyme: This type of inflores-cence is characterized by the end of main axis in a flower, which is followed by two lateral branches ending in flowers again. Actually this is a true cyme as in case of ixora, teak, jasmine, etc.4. Multiparous or Polychasial: The main axis ends in a flower and numbers of flowers are produced laterally in the same manner, i.e. in nerium, calotropis, etc.5. Special type: In this type hypanthodium (like peepal and fig), verticillasters (sacred basil, mentha, coleus blumi) cymose-umbel (onion) are included. Each of them has its special characters not covered in any type described above.Morphology of SeedsThe seed is a fertilized ovule and is a characteristic of Phanerogams. Parenchymatous body of the ovule known as nucellus contains embryo-sac in which fertilization of pollen cells takes place giving rise to embryo. The seeds are characterized by the presence of three parts known as embryo, endosperm and seed coat.Seed coatIt is the outermost layer of the seeds providing necessary protection to the embryo lying inside the seed. In case of dicotyledonous seeds normally, it is hard and may contain two layers; the outermost thick layer is known as testa while the inner one which is thin is known as tegumen. In monocotyledonous seeds, it is thin or even may be fused with the wall of the fruit.EmbryoIt is the main part of the seed. It consists of an axis having apical meristem for plumule, radicle the origin or root and adhered to it are one or two cotyledons, differentiating the plants as monocot or dicot.HilumCaruncleMicroplyleRapheTestaRediclePlumuleTegmenEndospermCotyledon(a) (b)Fig. 4.45 (a) Castor seed (b) L.S. of Castor seedEndospermIt is the nutritive tissue nourishing the embryo. It may be present or may not be present in the seed. Depending upon the presence or absence the seeds are classified as under:1. Endospermic or albuminous seeds.2. Nonendospermic or exalbuminous seeds.3. Perispermic seeds.1. Endospermic or albuminous seeds: In this seed, the part of the endosperm remains even up to the germination of seed and is partly absorbed by embryo. Therefore, seeds are known as endospermic seeds as in colchicum, isabgol, linseed, nux vomica, strophamthus,wheat and rice.2. Nonendospermic or exalbuminous seeds: During the development of these seeds, the endosperm is fully absorbed by embryo and endosperm, and is not represented in the seeds; hence, they are known as nonendospermic, e.g. sunflower, tamarind, cotton and soyabean.3. Perispermic seeds: Herein the nucleus develops to such an extent that it forms a big storage tissue and seeds are found to contain embryo, endosperm, perisperm and seed coat; e.g. pepper, cardamom, nutmeg, guinea grains.Seeds are characterized by the following descriptive terms: (a) Hilum: This is the point of attachment of seed to its stalk. (b) Micropyle: It is the minute opening of the tubular structure, wherefrom water is provided for the ger-mination of seeds. (c) Raphe: Raphe is described as longitudinal marking of adherant stalk of anatropous ovule. (d) Funicle: It is the stalk of the ovule attaching it to the placenta. (e) Chalza: This is the basal portion of ovule where stalk is attached.Special features of seedsSometimes, apart from the regular growth of seeds, addi-tional growth is visible in the form of appendages which attribute to their special features. They are described as: (i) Aril: Succulent growth from hilum covering the entire seeds as in nutmeg (mace) and yew seeds. (ii) Arillode: Outgrowth originating from micropyle and covering the seeds as in cardamom. (iii) Arista (awn): Stiff bristle-like appendage with many flowering glumes of grasses and found in strophanthus. (iv) Caruncle: A warty outgrowth from micropyle, i.e. castor, croton, viola moringa. (v) Hairs: Gossypium and calotropis are examples of this type of outgrowth. Strophanthus Calotropis Moringa NutmegFig. 4.46 Special features of seedsFunctions of SeedsSeed performs the following functions: 1. Reproduction, i.e. it germinates into new plant. 2. Spread of the species. 3. Species and varieties do not come to an end by suc-cessive formation of seeds by plant. Thus seeds are ‘means of perennation’.Chapter-04.indd 54 10/12/2009 3:50:26 PM55MORPHOLOGY OF DIFFERENT PARTS OF MEDICINAL PLANTMorphology of FruitsPhanerogams are said to be matured when they reach the flowering stage. The ovules of the flowers after fertilization get converted into seeds, whereas the ovary wall develops further to form the protective covering over the seed, which is known as fruit. In botany, this particular coating is also called pericarp.Pericarp consists of three different layers, one after the other as: 1. Epicarp: The outermost coating of the pericarp and may be thin or thick. 2. Mesocarp: A layer in between epicarp and endocarp, and may be pulpy or made up of spongy parenchy-matous tissue. 3. Endocarp: The innermost layer of the pericarp, may be thin or thick or even woody.It is not necessary that the fruits should have seeds. If the ovules do not fertilize, the seedless fruits are formed. Depending upon the number of carpels present in the flowers, and other structures, the fruits fall into (1) simple fruits, (2) aggregate fruits and (3) compound fruits.Simple fruitsFormed from the single carpel or from syncarpous gynoe-cium. Once again depending upon the mesocarp, whether it is dry or fleshy, they are classified as dry fruits and fleshy fruits. Dry fruits are further sub-classified into dehiscent and indehiscent fruits.Aggregate fruitsThese fruits get formed from many carpels or apocarpous gynoecium, e.g. raspberry.Compound fruitsIn this particular case many more flowers come together and form the fruits, e.g. figs, pineapple.FRUITSSimple fruits Aggregate fruits Compound fruitsDry fruits Fleshy fruitsDehiscents fruitsIndehiscents fruitsFalse fruitsSometimes it so happens that apart from the ovary and the other floral parts like thalamus, receptacle or calyx grow and form the part of the fruit, known as false fruit or pseudo-carp. Following are the few examples of pseudocarp in which other parts of the flower forming important part of the fruits are shown in the bracket. Strawberry (thalamus), cashew nut (peduncle and thalamus), apple (thalamus), marking nut (peduncle) and rose (thalamus) I. Dehiscent capsular fruits:1. Legume or pod: It is a dry monocarpellary fruit devel-oping from superior ovary, dehiscing by both the margins, i.e. senna, tamarind, pea.2. Capsule: It is a dry one to many-chambered fruit, developing from superior or poly carpellary ovary dehisc-ing in various forms, i.e. cardamon, cotton, datura, lobelia, colchicum, digitalis, poppy.3. Follicle: Similar to legumes and dehisces at one margin only, i.e. rauwolfia, anise, calotropis.4. Siliqua: A dry, two-chambered fruit, developing from bicarpellary ovary, multiseeded. It dehisces from base upwards as in radish mustard, etc.II. Indehiscest fruits:1. Achene: A dry, one-chambered, one-seeded fruit devel-oped from superior monocarpellary ovary. Pericarp is free of seed coat, i.e. clemantis, rose.2. Caryopsis or grain: Small, dry, one-seeded fruits, developing from simple pistil, pericarp fused with seed coat as in maize, rice, bamboo.3. Nut: Dry, one-seeded fruits developing from superior ovary, pericarp hard and woody, i.e. areca nut, marking nut, cashew nut.4. Samara: Dry, one- or two-seeded, winged fruit from supe-rior bi- or tricarpellary ovary, i.e. dioscorea, shorea, etc.5. Schizocarp: These are further divided into two sub-classes. (i) Lomentum: In this type of pod of legume is parti-tioned into one-seeded compartments as observed in acacia, ground nut, cassia fistula. (ii) Cremocarp: Dry, two-chambered fruit, developing from an inferior bicarpellary ovary. Splitting into two, indehiscent one-seeded pieces are called mericarps, i.e. coriander, cumin, fennel, dill, etc.Fleshy fruits:1. Drupe (Stone fruit): A fleshy one or more seeded fruit, with pericarp well differentiated into epicarp, fleshy mesocarp and hard endocarp as in mango, olive, coconut, etc.2. Berry: A fleshy, many-seeded fruit developed from superior, single carpel, i.e. tomato, guava, grapes, banana.3. Pepo: Pulpy, many-seeded fruit developing from one- or three celled inferior ovary, i.e. cucumber gourd, colocynth, water melon.4. Pome: Fleshy, one- or more-celled syncarpous fruit. Fleshy, part is thalamus, while actual fruit lies inside, e.g. apple, pear.5. Hesperidium: A superior, many-seeded fleshy fruit endocarp forming chambers; epicarp and mesocarp fused to form skin, e.g. orange, lemon.Chapter-04.indd 55 10/12/2009 3:50:26 PM56 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYDrupe of mangoPome of apple Hesperidium of orangeBerry of tomato Pepo of cucumberFig. 4.47 Types of fl ashy fruitsUses of fruits 1. Apart from the main source of food grains, i.e. wheat, jowar, fruits are also used for their high sugar value, minerals and vitamins. 2. Fleshy fruits like, papaya, mango, apple are used com-mercially as source of pectin. 3. Bayberry wax and olive oil are obtained industrially from fruits only. 4. Several fruits like chilies, black pepper caraway and cumin are used on large scale for the preparation of spices.Chapter-04.indd 56 10/12/2009 3:50:26 PM5.1. INTRODUCTIONA British systematic botanist J. Hutchinson published his work, The Families of Flowering Plants in 1926 on dicotyle-dons and in 1934 on monocotyledons. Hutchinson made it clear that the plants with sepals and petals are more primitive than the plants without petals and sepals on the assumption that free parts are more primitive than fused ones. He also believed that spiral arrangement of floral parts, numerous free stamens and hermaphrodite flowers are more primitive than unisexual flowers with fused stamens. He considered monochlamydous plants as more advanced than dicotyledons. Hutchinson’s system indicates the concept of phylogenetic classification and seems to be an advanced step over the Bentham and Hooker systemof classification. Hutchinson accepted the older view of woody and herbaceous plants, and fundamentally called them as Lignosae and Herbaceae. He revised the scheme of classification in 1959. He has divided the flowering plants into two phyla: phylum I—Gymnospermae (not elaborated by him) and phylum II—Angiospermae. The latter are divided into two sub-phyla: sub-phylum I—Dicotyledons and sub-phylum II—Monocotyledons.The division of angiosperms into these two large classes is based on the following factors: (1) In dicotyledons, the embryo bears two cotyledons, and in monocotyledons, it bears only one. (2) In dicotyledons, the primary root persists and gives rise to the tap root, while in monocotyledons, the primary root soon perishes and is replaced by a cluster of adventitious (fibrous) roots. (3) As a rule, venation is reticulate in dicotyledons and parallel in monocotyledons. Among monocotyledons, aroids, sarsaparilla (Smilax) and yams (Dioscorea), however, show reticulate venation, and among dicoty-ledons, Alexandrian laurel (Calophyllum) shows parallel venation. Further, in dicotyledons, the veinlets end freely in the mesophyll of the leaf, whereas in mono-cotyledons, veins or veinlets do not end freely. (4) The dicotyledonous flower usually has a pentamerous symmetry, sometimes tetramerous (as in Cruciferae and Rubiaceae), while the monocotyledonous flower has a trimerous symmetry. (5) In the dicotyledonous stem, the vascular bundles are arranged in a ring and are collateral and open, i.e. they contain a strip of cambium which gives rise to secondary growth. In the monocotyledonous stem, however, the bundles are scattered in the ground tissue and are collateral and closed. Hence, there is no secondary growth (with but few exceptions). Also the bundles are more numerous in monocotyledons than in dicotyledons. Further, they are more or less oval in monocotyledons and wedge shaped in dicotyledons. (6) In the dicotyledonous root, the number of xylem bundles varies from 2 to 6, seldom more, but in the monocotyledonous root there are many, seldom a limited number (5–8). It may also be noted that the cambium soon makes its appearance in the dicotyle-donous root as a secondary meristem and gives rise to secondary growth, but in the monocotyledonous root, the presence of cambium is rare. Hence, there is no secondary growth.Floral DiagramThe number of parts of a flower, their general structure, arrangement and the relation they bear to one another (aestivation), adhe sion, cohesion, and position with respect to the mother axis may be represented by a diagram known as the floral diagram. The floral diagram is the ground plan of a flower. In the diagram, the calyx lies outermost, the corolla internal to the calyx, the androecium in the middle, and the gynoecium in the centre. Adhesion and cohesion of members of different whorls may also be shown clearly by connecting the respective parts with lines. The black dot on the top represents the position of the mother axis (not the pedicel), which bears the flower. The axis lies behind Study of Different FamiliesCHAPTER5Chapter-05.indd 57 10/12/2009 3:50:41 PM58 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYthe flower and, therefore, the side of the flower nearest to the axis is called the posterior side, and the other side away from the axis the anterior side. The floral characteristics of species may be well represented by a floral diagram, whereas more than one diagram may be necessary to represent a genus or family.Floral FormulaThe different whorls of a flower, their number, cohesion and adhesion may be represented by a formula known as the floral formula. In the floral formula, K stands for calyx, C for corolla, P for perianth, A for androecium and G for gynoecium. The figures following the letters K, C, P, A and G indicate the number of parts of those whorls. Cohesion of a whorl is shown by enclosing the figure within brackets, and adhesion is shown by a line drawn on top of the two whorls concerned. In the case of the gynoecium, the position of the ovary is shown by a line drawn above or below G on the figure. If the ovary is superior, the line should be below it; and if inferior, the line should be on top. Thus, all the parts of a flower are represented in a general way by a floral formula.Besides, some symbols are used to represent certain features of flowers. Thus ♂ represents male, ♀ female, H hermaphrodite, ♂♀ dioecious, ♂-♀ monoecious, ♂ ♀ H polygamous, ⊕ actinomorphic, ·׀·zygomorphic, ∞ indefinite number of parts, etc.Features used in descriptions of Angiospermic plants:Habitat: Natural abode of the plant. �Habit: Herb (erect, prostrate, decumbent, diffuse, trailing, �twining or climbing), shrub (erect, straggling, twining or climbing), tree or any other peculiarity in the habit.Root: Nature of the foot; any special form. �Stem: Kind of stem—herbaceous or woody; cylindrical �or angular; hairy or smooth; jointed or not; hollow or solid; erect, prostrate, twining or climbing; nature of modification, if any.Le � af: Arrangement—whether alternate, opposite (super-posed or decussate) or whorled; stipulate or exstipulate; nature of the stipules, if present, simple or compound; nature of the compound leaf and the number of leaflets; shape and size; hairy or smooth; deciduous or persistent: venation; margin; apex; and petiole.Inflorescence: type of inflorescence. �Flower: sessile or stalked; complete or incomplete; �unisexual or bisexual; regular, zygomorphic, or irregu-lar; hypogynous, epigynous or perigynous; bracteate or ebracteate; nature of bracts and bracteoles, if present; shape, colour and size of the flower.Calyx: polysepalous or gamosepalous; number of sepals �or lobes; superior or inferior; aestivation; shape, size and colour.Corolla: polypetalous or gamopetalous; number of petals �or lobes; superior or inferior; aestivation; shape, size colour and scent; corona or any special feature. (When there is not much difference between the calyx and the corolla, the term perianth should be used. It may be sepaloid or petaloid, polyphyllous or gamophyllous, or free or epiphyllous).Androecium: number of stamens—definite (10 or less) �or indefinite (more than 10); free or united; nature of cohesion—monadelphous, diadelphous, polyadelphous, syngenesious or synandrous; nature of adhesion—epi-petalous or gynandrous, or any special feature; whether alternating with the petals (or corolla lobes) or opposite them. Length of stamens—general length; inserted or exerted; didynamous or tetradynamous; position of stamens—hypogynous, perigynous or epigynous; attach-ment of the anther and its dehiscence; anther lobes or appendages, if any,Gynoecium or pistil: number of carpels; syncarpous or �apocarpous; nature of style—long or short; stigmas— simple, lobed or branched; their number and nature—smooth or papillose; ovary—superior or inferior; number of lobes; number of chambers (loculi); nature of pla-centation; number and form of ovules in each loculus of the ovary.Fruit: kind of fruit. �Seeds: number of seeds in the fruit; shape and size; �albuminous or exalbuminous; nature of endosperm, if present.5.2. APOCYNACEAEHabit: These are mostly twining or erect shrubs and �lianes, a few herbs and trees with latex. Bicollateral bundles or internal phloem often present.Leaves: The leaves are simple, opposite or whorled, �rarely alternate.Flowers: The flowers are regular, bisexual and hypogy- �nous, in cymes. They are usually salver or funnel shaped, often with corona.Calyx: The sepals are five in number, and rarely four, �gamosepalous and often united only at the base.Corolla: There are five petals, rarely four. They are �gamopetalous and twisted.Androecium: There are five stamens, rarely four. They �are epipetalous, alternating with the petals, includedThe fame and reputation of the Shang Han Lun as well as its companion book, Chin Kuei Yao Lueh (Prescriptions from the Golden Chamber), is the historical origin of the most important classical herbal formulas that have become the basis of Chinese and Japanese-Chinese herbalism (called ‘Kampo’).With the interest in alchemy came the development of pharmaceutical science and the creation of a number of books including Tao Hong Jing’s (456–536) compilation of the Pen T’sao Jing Ji Zhu (Commentaries on the Herbal Classic) based on the Shen Nong Pen T’sao Jing, in 492. In that book 730 herbs were described and classified in six categories: (1) stone (minerals), (2) grasses and trees, (3) insects and animals, (4) fruits and vegetables, (5) grains and (6) named but unused. During the Sui dynasty (589–618) the study of herbal medicine blossomed with the creation of specialized books on plants and herbal medicine. Some of these set forth the method for the gathering of herbs in the wild as well as their cultivation. Over 20 herbals were chronicled in the Sui Shu JingJi Zhi (Bibliography of the History of Sui). These include the books Zhong Zhi Yue Fa (How to Cultivate Herbs) and the Ru Lin Cat Yue Fa (How to Collect Herbs in the Forest).From the Sung Dynasty (960–1276) the establishment of pharmaceutical system has been a standard practice throughout the country. Before the ingredients of Chinese medicine can be used to produce pharmaceuticals, they must undergo a preparation process, e.g. baking, simmer-ing or roasting. The preparation differs according to the needs for the treatment of the disease. Preparation methods, production methods and technology have constantly been improved over time.In 1552, during the later Ming Dynasty, Li Shi Zhen (1518–1593) began work on the monumental Pen T’sao Kan Mu (Herbal with Commentary). After 27 years and three revisions, the Pen T’sao Kan Mu was completed in 1578. The book lists 1892 drugs, 376 described for the first time with 1160 drawings. It also lists more than 11,000 prescriptions.Chapter-01.indd 4 10/12/2009 3:47:10 PM5HISTORY, DEFINITION AND SCOPE OF PHARMACOGNOSYAncient EgyptThe most complete medical documents existing are the Ebers Papyrus (1550 B.C.), a collection of 800 prescriptions, mentioning 700 drugs and the Edwin Smith Papyrus (1600 B.C.), which contains surgical instructions and formulas for cosmetics. The Kahun Medical Papyrus is the oldest—it comes from 1900 B.C. and deals with the health of women, including birthing instructions.However, it is believed that the Smith Papyrus was copied by a scribe from an older document that may have dated back as far as 3000 B.C. Commonly used herbs included: senna, honey, thyme, juniper, cumin, (all for digestion); pomegranate root, henbane (for worms) as well as flax, oakgall, pine-tar, manna, bayberry, ammi, alkanet, aloe, caraway, cedar, coriander, cyperus, elderberry, fennel, garlic, wild lettuce, nasturtium, onion, peppermint, papyrus, poppy-plant, saffron, watermelon, wheat and zizyphus-lotus. Myrrh, turpentine and acacia gum were also used.Ancient IndiaIn India knowledge of medicinal plants is very old, and medicinal properties of plants are described in Rigveda and in Atharvaveda (3500–1500 B.C.) from which Ayurveda has developed. The basic medicinal texts in this world region—The Ayurvedic writings—can be divided in three main ones (Charaka Samhita, Susruta Samhita, Astanga Hrdayam Samhita) and three minor ones (Sarngadhara Samhita, Bhava Prakasa Samhita, Madhava Nidanam Samhita). Ayurveda is the term for the traditional medicine of ancient India. Ayur means life and veda means the study of which is the origin of the term. The oldest writing—Charaka Samhita—is believed to date back six to seven centuries before Christ. It is assumed to be the most important ancient authoritative writing on Ayurveda. The Susruta Samhita is thought to have arisen about the same time period as the Charaka Samhita, but slightly after it Astanga Hrdayam and the Astanga Sangraha have been dated about the same time and are thought to date after the Charaka and Susruta Samhitas. Most of mentioned medicines origin from plants and animals, e.g. ricinus, pepper, lilly, valerian, etc.Ancient Greece and RomeGreek scientists contributed much to the knowledge of natural history. Hippocrates (460–370 B.C.) is referred to as father of medicine and is remembered for his famous oath which is even now administered to doctors. Aristotle (384–322 B.C.), a student of Plato was a philosopher and is known for his writing on animal kingdom which is consid-ered authoritative even in twentieth century. Theophrastus (370–287 B.C.), a student of Aristotle, wrote about plant kingdom. Dioscorides, a physician who lived in the first century A.D., described medicinal plants, some of which like belladonna, ergot, opium, colchicum are used even today. Pliny wrote 37 volumes of natural history and Galen (131–A.D. 200) devised methods of preparations of plant and animal drugs, known as ‘galenicals’ in his honour.Pharmacy separated from medicine and materia medica, the science of material medicines, describing collection, preparation and compounding, emerged. Even upto the beginning of twentieth century, pharma-cognosy was more of a descriptive subject akin mainly to botanical science, and it consisted of identification of drugs both in entire and powdered conditions and concerned with their history, commerce, collection, preparation and storage. The development of modern pharmacognosy took place later during the period 1934–1960 by simultaneous appli-cation of disciplines like organic chemistry, biochemistry, biosynthesis, pharmacology and modern methods and techniques of analytic chemistry, including paper, thin layer, and gas chromatography and spectophotometry. A fragment of Ebers Papyrus Hippocrates Aristotle and Plato Theophrastus Galen PlinyChapter-01.indd 5 10/12/2009 3:47:10 PM6 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYThe substances from the plants were isolated, their structures elucidated and pharmacological active constitu-ents studied. The development was mainly due to the following four events: 1. Isolation of penicillin in 1928 by William Fleming and large-scale production in 1941 by Florey and Chain. 2. Isolation of resperpine from rauwolfia roots and con-firming its hypotensive and tranquilizing properties. 3. Isolation of vinca alkaloids, especially vincristine and vinblasting. Vincristine was found useful in the treat-ment of leukaemia. These alkaloids also have anticancer properties. 4. Steroid hormones like progesterone were isolated by partial synthesis from diosgenin and other steroid saponins by Marker’s method. Cortisone and hydro-cortisone are obtained from progesterone by chemical and microbial reaction.This period can also be termed antibiotic age, as besides pencillin, active antibiotics like streptomycin, chloram-phenicol, tetracycline and several hundred antibiotics have been isolated and studied extensively.Some of the important aspects of the natural products that led to the modern development of drugs and phar-maceuticals are as follows: Isolation of phytochemicalsStrong acting substances such as glycosides of digitalis and scilla, alkaloids of hyoscyamus and belladonna, ergot, rauwolfia, morphine and other alkaloids of opium were isolated and their clinical uses studied.Structure activity relationshipTubocurarine and toxiferine from curare have muscle relax-ant properties because of quaternary ammonium groups. The hypotensive and tranquillizing actions of reserpine are attributed to the trimethoxy benzoic acid moiety which is considered essential. Mescaline and psilocybine have psy-chocative properties. Presence of a lactone ring is essential for the action of cardiac glycosides. Likewise anthraquinone glycosideswithin the corolla tube. The anthers usually connate around the stigma and apparently adnate to it. The disc is ring like or glandular. Gynoecium: The carpels are two or (2), apocarpous �or syncarpous, superior. When apocarpous, each ovary is one-celled with marginal placentation, and when syncarpous the ovary may be one celled with parietal placentation, or two celled with axile placentation. There are 2-∞ ovules in each.Fruit: There is a pair of follicles, barriers or drupes. �Chapter-05.indd 58 10/12/2009 3:50:42 PM59STUDY OF DIFFERENT FAMILIESSeeds: The seeds often have a crown of long, silky hairs �and they mostly have endosperm.Floral formula: ⊕ or ·׀·H K5 C5 A5 G–(2) Fig. 5.1 Floral diagram of apocynaceaeExamples: Rauwolfia, kurchi, devil tree, etc.5.3. COMPOSITAEH � abit: These are herbs and shrubs, rarely twiners, e.g. Mikarnia scandens, or trees, e.g. Vernonia arborea. They sometimes have internal phloem. Some genera have latex, e.g. Sonchus, Crvpis, Lactuca, Picris, etc.Leaves: The leaves are simple, alternate or opposite, �rarely compound.Inflorescence: The inflorescence is a head (or capitulum), �with an involucre of bracts.Flowers (florets): The flowers are of two kinds—the �central ones (called disc florets) are tubular, and the marginal ones (called ray florets) are ligulate. Sometimes all florets are of one kind, either tubular or ligulate. The disc flowers are regular, tubular, bisexual and epigynous, each usually in the axil of a bracteole.Calyx: The calyx is often modified into a cluster of hairs �called pappus, as in Tridax and Ageratum, or into scales, as in sunflower and Eclipta, or absent, as in water cress (Enhydra).Corolla: There are (5) petals. It is gamopetalous and �tubular. Androecium: The five stamens are epipetalous. The fila- �ments are free but the anthers united (syngenesious).Gynoecium: The carpels are (2), syncarpous. The ovary �inferior, one-celled with one basal, anatropous ovule. There is one style and the stigma is bifid.Fruit: The fruit is a cyp � scla.Floral formula: ⊕ H Kpappus or C(5) A(5) G(2)The ray florets are zygomorphic, ligulate, unisexual �(female), or sometimes neuter, as in sunflower, and epigynous, each usually in the axil of a bracteole. The calyx is usually modified into pappus. Sometimes it is scaly or absent. The corolla has (5) petals, is gamopeta-lous and ligulate (strap shaped). The gynoecium has disc florets shape. Floral formula: ·׀· ♀ Kpappus or o C(5) G–(2)Fig. 5.2 Floral Diagram of compositae (disc fl oret)Examples: Sunflower, pyrethrum, artemisia, etc.5.4. CONVOLULACEAEHabit: � These are mostly twiners, often with latex and bicollateral vascular bundles or internal phloem.Leaves: � The leaves are simple, alternate and exstipu-late.Inflorescence: The inflorescence is cymose. The flowers �are regular, bisexual, hypogynous, often large and showy.Calyx: There are five sepals, usually free. The odd one �is posterior, imbricate and persistent.Corolla: There are (5) petals, is gamopetalous, funnel �shaped, twisted in bud and sometimes imbricate.Androecium: The five stamens are epipetalous, alternat- �ing with the petals.Gynoecium: There are (2) carpels, rarely more, connate. �The ovary is superior, with a disc at the base. It is two celled, with two ovules in each cell, or sometimes four-celled with one ovule in each cell. The placentation is axile.Fruit: The fruit is � a berry or a capsule. Floral formula: ⊕ H K5 C(5) A5 G(2)Fig. 5.3 Floral diagram of convolvulaceaeExamples: Sweet potato (Ipomoea batatas), jalap (Ipomoea purga), etc.Chapter-05.indd 59 10/12/2009 3:50:42 PM60 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRY5.5. CRUCIFERAEHab � it: These are annual herbs.Leaves: The leaves are radical and cauline, simple, alter- �nate, often lobed, or rarely pinnately compound.Inflorescence: A raceme (corymbose towards the top). �Flowers: The flowers are regular and cruciform, bisexual �and complete hypogynous.Calyx: They are sepals, 2+2, which are free, and in �two whorls.Corolla: There are four petals, free, in one whorl. They �alternate with the sepals. They are cruciform. Each petal has distinct limb and claw.Androecium: There are six stamens in two whorls, two �short, outer ones and four long, inner ones (tetrady-namous).Gynoecium: There are two syncarpous carpels. The �ovary is superior, at first one-celled, but later two-celled owing to the development of a false septum. There are often many ovules in each cell, sometimes only two. They are anatropous or campylotropous. The placenta-tion is parietal.Fruit: The fruit is a long, narrow siliqua or a short, �broad silicula.Seeds: These are exalbuminous. The embryo is curved. �The seeds remain attached to a wiry framework, called the replum, which surrounds the fruit.Floral formula: ⊕ H K2+2 C4 A2+4 G(2)Fig. 5.4 Floral diagram of cruciferaeExamples: Black mustard (Brassica nigra).5.6. GRAMINEAEHabit: � These are herbs, rarely woody, as bamboos. They are very widely distributed all over the earth.Stem: This is cylindrical and has distinct nodes and �internodes (sometimes hollow), called culm.Leaves � : These are simple, alternate and distichous. They have a sheathing leaf base that is split open on the side opposite the leaf blade. There is a hairy structure, called the ligule, at the base of the leaf blade.Inflorescence: This is usually a spike or a panicle of �spikelets. Each spikelet consists of one or few flowers (not exceeding five), and its base-bears two empty bracts or glumes (GI, GII), one placed a little above and opposite the other. A third glume, called the lemma or flowering glume, stands opposite the second glume. The lemma encloses a flower in its axil. It may have a bristle-like appendage, long or short, known as the awn. Opposite the flowering glume or lemma, there is a somewhat smaller, two-nerved glume called the palea. The spikelet may be sessile or stalked.Flowers: These are usually bisexual, sometimes unisexual �and monoecious.Perianth: This is represented by 2- or 3-minute scales, �called the lodicules, at the base of the flower. These are considered to form the rudimentary perianth.Androecium � : There are three stamens, or sometimes six, as in rice and bamboo. The anthers are versatile and pendulous.Gynoecium: The carpels are generally considered to �number (three), reduced to one by their fusion or by the suppression of two. The ovary is superior and one-celled, with one ovule. The styles usually number two (three in bamboos, and two fused into one in maize, rarely one). They may be terminal or lateral. The stigmas are feathery.Fruit: � The fruit is a caryopsis.Seed: � This is albuminous. Pollination by the wind is most common. Self-pollination occurs in a few cases, as in wheat. Floral Formula: HP Lodicules2 or 3 A3 or 6 G(3) or 1GIIGIFig. 5.5 Floral diagram of gramineaeExamples: Rice, maize, bamboo, etc. Chapter-05.indd 60 10/12/2009 3:50:42 PM61STUDY OF DIFFERENT FAMILIES5.7. LABIATAEHabit: These are herbs and undershrubs with square �stems.Leaves: These are simple, opposite or whorled, exstipu- �late and have oil glands.Flowers: This is a zygomorphic, bilabiate, hypogynous �and bisexual.Inflorescence: This is a verticillaster. It is often reduced �to a true cyme, as in tulsi. Calyx: The petals are (five in number), gamopetalous and �bilabiate, i.e. two lipped. The aestivation is imbricate.Androecium: The stamens are four and didynamous. �Sometimes there are only two, as in sage. They are epipetalous.Gynoecium: � The carpels are (2) and syncarpous. The disc is prominent. The ovary is four-lobed and four-celled, with one ovule in each cell, ascending from the base of ovary. The style is gynobasic, i.e. it develops from the depressed centre of the lobed ovary. The stigmais bifid. Fruit: This is a group of four nutlets, each with one seed. �The seed has only scanty endosperm, or even none.Floral formula: ·׀·H K(5) C(5) A4 G(2)Fig. 5.6 Floral diagram of labiataeExamples: Tulsi, mentha, etc.5.8. LEGUMINOSAEHabit: These are herbs, shrubs, trees, twiners or climb- �ers.Roots: The roots of many species, particularly of � Pap-ilionaceae, have tubercles.Leaves: These are alternate, pirnnately compound, and �rarely simple, as in rattlewort (Crotalaria sericea), camel’s foot tree (bauhinid) and some species of desmodium, e.g. D. gangeticum, with a swollen leaf-base known as the pulvinus. There are two, usually free, stipules.Flowers: These are bisexual and complete, regular or �zygomorphic or irregular, and hypogynous or slightly perigynous.Calyx: There are usually 5 or (5) sepals, with the odd �one anterior (away from the axis). Sometimes there are four sepals. They may be united or free.Corolla: There are usually five petals, with the odd one �posterior (towards the axis). Sometimes there are four petals, free or united.Androecium: There are usually 10 or more stamens �(often less than 10 by reduction) free or united.Gynoecium: There is one carpel. The ovary is one-celled, �with one to many ovules. It is superior and the placen-tation is marginal. The ovary often borne on a long or short stalk is called the stipe or gynophore.Fruit: This is mostly a legume or pod (dehiscent), or �sometimes a lomentum (indehiscent).This is the second biggest family among the dicotyledons, and has varying characteristics. As such, it has been divided into the following sub-families: papilionaceae, caesalpin-ieae and mimoseae. The division is primarily based on the characteristics of the corolla and the stamens. PapilionaceaeHabit: Herbs, shrubs, trees and climbers. �Leaves: Unipinnate, sometimes trifoliate, rarely simple; �stipels often present.Inflorescence: Usually a raceme. �Flowers: Zygomorphic, polypetalous and papiliona- �ceous.Calyx: Usually has five sepals, gamosepalous, often �imbricate, sometimes valvate.Corolla: Usually has five petals, free, of very unequal �sizes, the posterior and largest one being the vexillum or standard, the two lateral ones being the wings or alae, and the two innermost ones (apparently united) forming the keel or carina; aestivation vexillary.Androecium: Stamens 10, diadelphous (9) + 1, rarely �10, free, as in coral tree (erythrina), or (10), connate, as in rattlewort (crotalaria).Floral formula: ·׀·H K(5) C5 A(9) + 1 G1Fig. 5.7 Floral diagram of papilionaceaeExamples: Methi, indigo, bengal gram, etc.Chapter-05.indd 61 10/12/2009 3:50:42 PM62 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYCaesalpinieaeHabit: � Shrubs trees, rarely climbers or herbs. Leaves: Unipinnate or bipinnate, rarely simple, as in �camel’s foot tree (Bauhinia); stipels absent.Inflorescence: Mostly a raceme. �Flowers: Zygomorphic or irregular and polypetalous. �Calyx: Sepals usually have five, polysepalous (sometimes � gamosepalous), imbricate. Corolla: Usually have five petals, free, subequal or �unequal, the odd or posterior one (sometimes very small) always innermost; aestivation imbricate. Androecium: There are 10 stamens, or less by reduc- �tion; free.Floral formula: ·׀·H K5 C5 A10 G1Fig. 5.8 Floral diagram of CaesalpinieaeExamples: Indian Senna, Saraca indica, etc.MimoseaeHabit: Shrubs and trees, sometimes herbs or woody �climbers. Leaves: Bipinnate; stipels present or absent. �Inflorescence: A head or a spike. �Flowers: Regular, often small and aggregated in spheri- �cal heads. Calyx: (5) or (4) sepals, generally gamosepalous, �valvate. Corolla: (5) or 4) petals, mostly gamopetalous; aestiva- �tion valvate. Androecium: Usually ∞ stamens, sometimes 10 (as in �Entada, Neptunia, Prosopis and Parkia), free, often united at the base; pollen often united in small masses.Floral formula: ⊕ H K(5 – 4) C(5 – 4) A ∞ or 10 G1Examples: Catechu and other species of acacia, Mimosa pudica, etc.Fig. 5.9 Floral diagram of mimoseae5.9. LILIACEAEH � abit: These are herbs and climbers, and rarely shrubs or trees with a bulb or rhizome, or with fibrous roots.Leaves: These are simple, radical or cauline, or both. �Flowers: The flowers are regular, bisexual (rarely uni- �sexual) dioecious, as in smilex. They are trimerous and hypogynous. The bracts are usually small and scarious (thin, dry and membranous).Inflorescence: � This may be a spike, raceme, panicle or umbel, often on a scape. Perianth: The perianths are petaloid. There are usually �six in two whorls. They may be 3+3 and free (polyphyl-lous), or (3+3), and united (gamophyllous).Androecium: There are six stamens in two whorls, 3+3, �rarely free or united with the perianth (epiphyllous) at the base. The anthers are often dorsifixed.Gynoecium � : There are (3) carpels (syncarpous). The ovary is superior and three celled. There are usually ∞ ovules in two rows in each loculus. The placentation is axile. There are (3) or 3 styles.Fruit: � This may be a berry or capsule.Seeds: The seeds are album � inous.Floral formula: ⊕ H P3 + 3 or (3 + 3) A3 + 3 G(3)Fig. 5.10 Floral diagram of liliaceaeExamples: Onion, garlic, aloe, colchicum, etc.Chapter-05.indd 62 10/12/2009 3:50:42 PM63STUDY OF DIFFERENT FAMILIES5.10. PAPAVERACEAEHabit: � They are mostly herbs with milky or yellowish latex.Leaves: The leaves are radical and cauline, simple and �alternate, often lobed.Flowers: These are solitary, often showy, regular, bisexual �and hypogynous.Calyx: The sepals are typically two or sometimes three, �free, caducous.Corolla: There are petals 2+2 or 3+3, arranged rarely �more, in two whorls (rarely three), large, free, rolled or crumpled in the bud, caducous and imbricate.Androecium: Stamens � α, sometimes two or four. They are free.Gynoecium: The carpels (2- ∞), (4–6) in argemone � . It is syncarpous. The ovary is superior, 1-chambered, or spuriously 2- to 4-chambered, with 2-∞ parietal placen-tae which may project inwards, as in poppy (papaver). The stigmas are distinct or sessile and rayed over the ovary, as in poppy. The ovules are numerous.Fruit: This is a septicidal capsule dehiscing by or opening �by pores. There are many seeds, with oily endosperm.Floral formula: ⊕ H K 2 or 3 C 2+2 or 3+3 A ∞ G (2-∞)Fig. 5.11 Floral diagram of Papaveraceae (Argemone)Examples: Argemone mexicana, Opium poppy (Papavera somniferum), etc.5.11. RUBIACEAEHabit: These are herbs (erect or prostrate), shrubs, trees �and climbers, sometimes thorny.Leaves: The leaves are simple, entire, opposite (decus- �sate) or whorled, with interpetiolar (sometimes intra-petiolar) stipules.Flowers: The flowers are regular, bisexual, epigynous, �sometimes dimorphic, as in some species of randia and oldenlandia.Inflorescence: The inflorescence is typically cymose, �frequently dichasial and branched, sometimes in globose heads.Calyx: There are usually four sepals, sometimes five. It �is gamosepalous. The calyx tube adnates to the ovary.Corolla: There are usually four sometimes five. It is �gamopetalous, generally rotate. The aestivation is valvate, imbricate or twisted.Androecium: The stamens are as epipetalous, inserted �within or at the mouth of the corolla tube, alternating with the corolla lobes.Gynoecium: � The carpels are two, syncarpous. The ovary is inferior, commonly two-locular, with 1-∞ ovules in each. The disc is usually annular, at the base of the style.Fruit: � The fruit is a berry, drupe or capsule.Seeds: The seed has fleshy or horny endosperm. �Floral formula: ⊕ H K (4 – 5) C(4 – 5) A4 - 5 G2Fig. 5.12 Floral diagram of RubiaceaeExamples: Cinchona, Ipecac, etc.5.12. RUTACEAEHabit: These are shrubs and trees (rarely herbs). �Leaves: The leaves are simple or compound, alternate �or rarely opposite and gland dotted.Flowers: These are regular, bisexual and hypogynous. �The disc below the ovary is prominent and ring or cap like.Calyx: There are four or five sepals free or connate �below and imbricate.Corolla: Petals four or five � , free, imbricate.Androecium: The number of stamens varies, they can �be as many, or more often twice, as many, as the petals (obdiplostemonous), or numerous, as in citrus and aegle. They are free or united in irregular bundles (polyadel-phous), and inserted on the disc.Gynoecium: � There are generally (4) or (5) carpels, or ∞, as in citrus. They are syncarpous or free at the base and united above, and either sessile or seated on the disc. The ovary is generally four- or five-locular, or multilocular as in citrus, with axile placentation (parietal in limonia only). There are usually 2-∞ (rarely 1) ovules in each loculus, arranged in two rows.Fruit: � This is a berry, capsule or hesperidium.Chapter-05.indd 63 10/12/2009 3:50:43 PM64 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYSeeds: The seeds may or may not have an endosperm. �Polyembryony is frequent in Citrus, e.g. lemon and orange (but not pummelo and citron).Floral formula: ⊕ H K 4–5 C 4–5 A 8, 10 or ∞ G (4, 5 or ∞)Fig. 5.13 Floral diagram of RutaceaeExamples: Citrus limon, Citrus aurentium, Aegle marmelos (wood apple).5.13. SCROPHULARIACEAEHabit: Th � ese are mostly herbs and under-shrubs.Leaves: These are simple, alternate, opposite or whorled, �exstipulate, and sometimes exhibit heterophylly.Inflorescence: This is usually racemose (raceme or spike), �and sometimes cymose (dichasium). It can be axillary or terminal. The flowers are solitary in some species.Flowers: These are zygomorphic, two-lipped and some- �times personate. They often have a great diversity of form. They are bisexual and hypogynous. Bracts and bracteoles are generally present.Calyx: The sepals are (5), gamosepalous, five-lobed and �often imbricate.Corolla: The petals are (5), gamopetalous, often two- �lipped and sometimes spurred or saccate. They are medianly zygomorphic, very rarely regular (as in Sco-paria), and imbricate.Androecium: The stamens are four, didynamous, some- �times two, arching over in pairs. The posterior stamen is absent or a staminode. The anthers are divaricate.Gynoecium: The carpels are (2) and syncarpous. The �ovary is superior, bilocular and antero-posterior (and not oblique as in solanaceae). The placentation is axile. The stigma is simple or bilobed. There are usually many ovules, though sometimes only a few. The disc is ring-like around the base of the ovary, sometimes unilateral.Fruit: This is mostly a capsule and sometimes a berry. �Seeds: T � hese are usually numerous, minute and endospermic.Floral formula: ·׀· H K(5) C(5) A4 or 2 G(2)Fig. 5.14 Floral diagram of scrophulariaceaeExamples: Digitalis purpurea, brahmi (Baccopa monnieria), etc.5.14. SOLANACEAEHabit: These are herbs and shrubs; bicollateral bundles �or internal phloem are often present.Leaves: These are simple, sometimes pinnate, as in �tomato, and alternate.Flowers: These are regular, seldom zygomorphic, as in �Brunfelsia, bisexual and hypogynous. Calyx: The sepals are (5), united and persistent. �Corolla: The petals are (5) and united. It is usually �funnel or cup shaped, five lobed. The lobes are valvate or twisted in the bud. Androecium: The stamens are five, epipetalous and alter- �nate with the corolla lobes. The anthers are apparently connate and often open by means of pores. Gynoecium: � The carpels are (2) and syncarpous. The ovary is superior and obliquely placed. It is two celled or sometimes four celled, owing to the development of a false septum, as in tomato and thorn apple. There are many ovules in each chamber. The placentation is axile.Fruit: � The fruit is a berry or capsule with many seeds.Floral formula: ⊕ H K(5) C(5) A5 G–(2)Fig. 5.15 Floral diagram of solanaceaeExamples: Atropa belladona, tomato, capsicum, datura, etc.Chapter-05.indd 64 10/12/2009 3:50:43 PM65STUDY OF DIFFERENT FAMILIES5.15. UMBELLIFERAEHabit: These are herbs (rarely shrubs). The stem is �usually fistular.Leaves: The leaves are alternate, simple, often much �divided, sometimes decompound; petiole usually sheath-ing at the base.Flowers: The flowers are regular (actinomorphic) or �sometimes zygomorphic, epigynous, bisexual or polyga-mous. The outer flowers are sometimes rayed; mostly protandrous. The bracts are in the form of an involu-cre.Inflorescence: It is an umbel, usually compound or in �a few cases simple as in centella.Calyx: There are five sepals. They are free, adnate to �the ovary, often considerably reduced in size.Corolla: The petals are five, rarely absent, free, adnate to �the ovary and sometimes unequal. The margin is often curved inwards, valvate or imbricate.Androecium: There are five stamens, which are free, �alternating with the petals, epigynous. The filaments are bent inwards in the bud; anthers introrse.Gynoecium: The carpels are two, syncarpous. The ovary �is inferior, two-celled, antero-posterior, crowned by a two-lobed, epigynous disc (stylopodium), with two free styles arising from it. The stigmas capitate. There are two ovules, solitary in each cell and pendulous.Fruit: � The fruit is a cremocarp consisting of two inde-hiscent carpels laterally or dorsally compressed, breaking up into two parts, called mericarps, which are attached to a slender, often forked axis (carpophore). Each mericarp usually shows five longitudinal ridges and oil canals (vittae) in the furrows.Seeds: There are two seeds, one in each mericarp; �albuminous.Floral formula: ⊕ or ·׀· H K5 C5 A10 G(2)Fig. 5.16 Floral diagram of umbelliferaeExamples: Fennel, coriender, caraway, dill, etc.Chapter-05.indd 65 10/12/2009 3:50:43 PMPART C CULTIVATION, COLLECTION, PRODUCTION AND UTILIZATION OF HERBAL DRUGSChapter-06.indd 67 10/12/2009 4:07:07 PM6.1. INTRODUCTIONThe crude drugs which reach the market and pharmaceuti-cal industries will have passed through different stages that have some effect in the nature and amount of active con-stituents responsible for therapeutic activity. Those stages are to be concerned more in order to make a drug useful to the mankind by all means. This chapter concerns regarding such parameters which has some effect over plants.Cultivation produces improved quality of plants. It helps in selecting the species, varieties or hybrids that have the desired phytoconstituents due to the controlled environ-mental growth better plant product is obtained and makes the collection and processing steps easier when compared to wild sources. Cultivation results in obtaining plants with maximum secondary metabolites. It leads to industrializa-tion in the country by the regular supply of plants. Serves as a useful tool for research purposes.The advantages of cultivation may be briefly summarized as follows: 1. It ensures quality and purity of medicinal plants. Crude drugs derive theirutility from chemical contents in them. If uniformity is maintained in all operations during the process of cultivation, drugs of highest quality can be obtained. Cultivation of rhizomes demands an adequate quantity of fertilizers and proper irrigation. Systematic cultivation results in raising a crop with maximum content of volatile oil and other constituents. The examples of ginger, turmeric and liquorice can be cited to illustrate this point. If the cultivated plants are kept free of weeds, the contami-nation of crude drugs can be conveniently avoided. 2. Collection of crude drugs from cultivated plants gives a better yield and therapeutic quality. However, it is a skilled operation and requires some professional excellence, if the collection of crude drugs for market is done from cultivatedplants by skilled and well-experienced personnel, the high yield and therapeutic quality of drugs can be maintained. For example, col-lection of latex from poppy capsules and oleo-resins from Pinus species, if done by experienced persons, can result in better yield of crude drugs. Preservation of green colour of senna leaves and minimizing the deterioration of cardiac glycosides in freshly collected leaves of digitalis can be achieved only by highly skilled labour. 3. Cultivation ensures regular supply of a crude drug. In other words, cultivation is a method of crop-planning. Planning a crop cultivation regularizes its supply and as a result the industries depending upon crude drugs do not face problem of shortage of raw material. 4. The cultivation of medicinal and aromatic plants also leads to industrialization to a greater extent. The cultivation of coffee and cocoa in Kerala has given rise to several cottage and small scale industries. The cultivation of cinchona in West Bengal has led to the establishment of the cinchona-alkaloid factory near Darjeeling. The government owned opium factory at Ghaziabad is an eloquent testimony to the significance of well planned cultivation of poppy. 5. Cultivation permits application of modern technologi-cal aspects such as mutation, polyploidy and hybridiza-tion.6.2. SOILS, SEEDS AND PROPAGATION MATERIALThe physical, chemical and microbiological properties of the soil play a crucial role in the growth of plants. Water holding capacity of different sizes of soil too affects the plants. The calcium present in the soil would be very much useful for some plants where as the others does not require calcium. The seed to be used for cultivation should be identified botanically, showing the details of its species, chemotype and origin. The seeds should be 100% traceable. The parent material should meet standard requirements regarding the Cultivation, Collection and Processing of Herbal DrugsCHAPTER6Chapter-06.indd 69 10/12/2009 4:07:07 PM70 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYpurity and germination. It should be free from pests and diseases in order to guarantee healthy plant growth. Pref-erence should be given to the resistant or tolerant species. Plant materials or seeds derived from genetically modified organisms have to comply with national and European Union regulations. Season when the seeds should be sown and at what stage a seed should be sown should be prede-termined. Few seeds such as cinnamon losses its viability if stored for long period and the percentage of germination would be less for the seeds which were long stored.Methods of Plant PropagationMedicinal plants can be propagated by two usual methods as applicable to nonmedicinal plants or crops. These methods are referred as sexual method and asexual method. Each of these methods has certain advantages, and also, disad-vantages.1. Sexual method (seed propagation)In case of sexual method, the plants are raised from seeds and such plants are known as seedlings. The sexual method of propagation enjoys following advantages: 1. Seedlings are long-lived (in case of perennial drugs) and bear more heavily (in case of fruits). Plants are more sturdier. 2. Seedlings are comparatively cheaper and easy to raise. 3. Propagation from seed has been responsible for pro-duction of some chance-seedlings of highly superior merits which may be of great importance to specific products, such as orange, papaya, etc. 4. In case of plants where other vegetative methods cannot be utilized, propagation from seeds is the only method of choice.Sexual method suffers from following limitations 1. Generally, seedling trees are not uniform in their growth and yielding capacity, as compared to grafted trees. 2. They require more time to bear, as compared to grafted plants. 3. The cost of harvesting, spraying of pesticides, etc. is more as compared to grafted trees. 4. It is not possible to avail of modifying influence of root stocks on scion, as in case of vegetatively propagated trees.For propagation purpose, the seeds must be of good quality. They should be capable a high germination rate, free from diseases and insects and also free from other seeds, used seeds and extraneous material. The germina-tion capacity of seeds is tested by rolled towel test, excised embryo test, etc. The seeds are preconditioned with the help of scarcification to make them permeable to water and gases, if the seeds are not to be germinated in near future, they should be stored in cool and dry place to maintain their germinating power. Long storage of seeds should be avoided.Before germination, sometimes a chemical treatment is given with stimulants like gibberellins, cytokinins, ethylene, thiourea, potassium nitrate or sodium hypochlorite. Gib-bereilic acid (GA3) promotes germination of some type of dormant seeds and stimulates the seedling growth. Many freshly harvested dormant seeds germinate better after soaking in potassium nitrate solution. Thiourea is used for those seeds which do not germinate in dark or at high temperatures.Methods of sowing the seedsNumerous methods of sowing the seeds of the medicinal plants are in practice. Few of them using seeds for cultiva-tion are described:Broadcasting: If the seeds are extremely small the sowing is done by broadcasting method. In this method the seeds are scattered freely in well prepared soil for cultivation. The seeds only need raking. If they are deeply sown or covered by soil, they may not get germinated. Necessary thinning of the seedlings is done by keeping a specific distance, e.g. Isabgol, Linseed, Sesame, etc.Dibbling: When the seeds of average size and weight are available, they are sown byplacing in holes. Number of seeds to be put in holes vary from three to five, depending upon the vitality, sex of the plants needed for the purpose and the size of the plant coming out of the seeds.For example, in case of fennel four to five fruits are put in a single hole keeping suitable distance in between two holes. In case of castor, only two to three seeds are put. In case of papaya, the plants are unisexual and only female plants are desired for medicinal purposes. Hence, five to six seeds are put together and after the sex of the plants is confirmed, healthy female plant is allowed to grow while male plants and others are removed.Miscellaneous: Many a times the seeds are sown in nursery beds. The seedlings thus produced are transplanted to farms for further growth, such as cinchona, cardamom, clove, digitalis, capsicum, etc.Special treatment to seeds: To enhance germination, special treatments to seeds may be given, such as soaking the seeds in water for a day e.g. castor seeds and other slow-germinating seeds. Sometimes, seeds are soaked in sulphuric acid e.g. henbane seeds. Alter natively, testa is partially removed by grindstone or by pounding seeds with coarse sand, e.g. Indian senna. Several plant hormones like gibberellins, auxins are also used.2. Asexual methodIn case of asexual method of vegetative propagation, the vegetative part of a plant, such as stem or root, is placed in such an environment that it develops into a new plant.Chapter-06.indd 70 10/12/2009 4:07:07 PM71CULTIVATION, COLLECTION AND PROCESSING OF HERBAL DRUGSAsexual propagation enjoys following advantages: 1. There is no variation between the plant grown and plant from which it is grown. As such, the plants are uniform in growth and yielding capacity. In case of fruit trees, uniformity in fruit quality makes harvesting and marketing easy. 2. Seedless varieties of fruits can only be propagated vegetatively e.g. grapes, pomegranates and lemon. 3. Plants start bearing earlier as compared to seedling trees. 4. Budding or grafting encourages disease-resistant variet-ies of plants. 5. Modifying influence of root-stockson scion can be availed of. 6. Inferior or unsuitable varieties can be over-looked.It suffers from following disadvantages: 1. In comparison to seedling trees, these are not vigorous in growth and are notlong-lived. 2. No new varieties can be evolved by this method.Asexual method of vegetative propa gation consists of three types:(a) Natural methods of vegetative propagation.(b) Artificial methods of vegetative propagation.(c) Aseptic method of micropropagation (tissue-cul-ture).(a) Natural methods of vegetative propagation: It is done by sowing various parts of the plants in well pre-pared soil. The following are the examples of vegetative propagation.Bulbs Squill, garlicCorms Colchicum, saffronTubers Jalap, aconite, potatoRhizomes Ginger, turmericRunners PeppermintSuckers Mint, pineapple, chrysanthemum, bananaOffsets Aloe, valerianStolons Arrow-root, Liquorice(b) Artificial methods of vegetative propagations: The method by which plantlets or seedlings are produced from vegetative part of the plant by using some technique or process is known as artificial method of vegetative propaga-tion. These methods are classified as under:1. Cuttings (i) Stem cuttings(a) Soft wood cuttings: Berberry.(b) Semi hard wood cuttings: Citrus, camellia.(c) Hard wood cuttings: Orange, rose and bougainvil-lea. (ii) Root cuttings: Brahmi. (iii) Leaf cuttings: Bryophyllum. (iv) Leaf bud cuttings.2. Layering (i) Simple layering: Guava, lemon (ii) Serpentine layering: jasmine, clematis (iii) Air layering (Gootee): Ficus, mango, bougainvillea, cashew nut (iv) Mount layering (v) Trench layering (vi) Tip layering3. Grafting (i) Whip grafting: Apple and rose (ii) Tongue grafting (iii) Side grafting: Sapota and cashew nut (iv) Approach grafting: Guava and Sapota (v) Stone grafting: Mango(c) Aseptic methods of micropropagation (tissue culture)It is a novel method for propagation of medicinal plants. In micropropagation, the plants are developed in an artificial medium under aseptic conditions from fine pieces of plants like single cells, callus, seeds, embryos, root tips, shoot tips, pollen grains, etc. They are also provided with nutritional and hormonal requirements.Preparation and Types of Nursery BedsFor various genuine reasons, seeds cannot be sown directly into soil i.e. very small size (Isabgol, tulsi) high cost, poor germination rate and long germination time (Cardamom, Coriander). Under such circumstances, seeds are grown into the nursery bed which not only is economical, but one can look after the diseases (if any) during germination period. Small size of beds can be irrigated conveniently along with fertilizers, as and when necessary. There are four types of nursery beds. 1. Flat bed method 2. Raised bed method 3. Ridges and furrow method 4. Ring and basin methodTaking into consideration the amount of water and type of soil required for a particular seed one should select the type. Methods of IrrigationWater is essential for any type of cultivation. After study-ing the availably and requirement of water for a specific crop, one has to design his own irrigation system at the reasonable cost.Chapter-06.indd 71 10/12/2009 4:07:07 PM72 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYFollowing methods of irrigation are known traditionally in India. The cultivation has an option after giving due consideration to the merits and demerits of each. 1. Hand watering: economical and easy to operate. 2. Flood watering: easy to operate, results in wastage of water. 3. Boom watering: easy to operate, but restricted utility. 4. Drip irrigation: Scientific, systematic and easy to operate; costly. 5. Sprinkler irrigation: Costly, gives good results.6.3. GOOD AGRICULTURAL PRACTICESDepending on the method of cultivation different Standard Operating Procedures for cultivation should be followed by the cultivators. A suitable area for the cultivation and the standard operation procedures for the cultivation should be developed depending upon the needs of the plants. Medici-nal and aromatic plants should not be grown in soils which are contaminated by sludge and not contaminated by heavy metals, residues of plant protection products and any other unnatural chemicals, so the chemical products (pesticide and herbicide) used should be with as minimum negative effect as possible, human faeces should be avoided. Depending upon the soil fertility and the nutritional requirement of medicinal plants the type of the fertilizer and the amount of the fertilizer to be used is determined. Products for chemical plant protection have to conform to the European Union’s maximum residue limits. Proper irrigation and drainage should be earned out according to the climatic condition and soil moisture. The soil used for cultivation should be well aerated. The use of pesticides and herbicides has to be documented. Irrigation should be minimized as much as possible and only be applied according to the needs of the plant. Water used for irrigation should be free from all possible forms of contaminants and should comply with national and European Union quality standards. The area for cultivation should be strictly prohibited from the con-taminations like house garbage, industrial waste, hospital refuse and feces. Field management should be strengthened and proper measures like pruning, shading etc. should be provided for increasing the yield of the active constituent and maintain the consistency of the yield. The pests used should give high efficacy, hypotoxicity, and low residue at the minimum effective input so that the residue of pesticides are also reduced and protected from ecological environment.Application and storage of plant protection products have to be in conformity with the regulations of manufacturers and the respective national authorities. The application should only be earned out by qualified staff using approved equipment. The nutrient supply and chemical plant protec-tion, should secure the marketability of the product. The buyer of the batch should be informed about the brand, quantity and date of pesticide use in written.Though several countries in the world have a rich heri-tage of herbal drugs, very few have their claim for their procurement of crude drugs only from cultivated species. Our reliance on wild sources of crude drugs and the lack of information on the sound cultivation and maintain-ing technology of crude drugs have resulted in gradual depletion of raw material from wild sources. Though the cultivation of medicinal plants offers wide range of advantages over the wild sources, it can be an uneconomi-cal process for some crude drugs which occur abundantly in nature e.g. nux vomica, acacia etc. On the other hand, crude drugs like cardamom, clove, poppy, tea, cinchona, ginger, linseed, isabgol, saffron, peppermint, fennel, etc. are obtained majorly from cultivated plants. The cultiva-tion of crude drugs involves keen knowledge of various factors from agricultural and pharmaceutical sphere, such as soil, climate, rainfall, irrigation, altitude, temperature, use of fertilizers and pesticides, genetic manipulation and biochemical aspects of natural drugs. When all such factors are precisely applied, the new approach to scientific cultiva-tion technology emerges out.6.4. FACTORS AFFECTING CULTIVATIONCultivation of medicinal plants offers wide range of advan-tages over the plants obtained from wild sources. There are few factors to concern which have a real effect on plant growth and development, nature and quantity of secondary metabolites. The factors affecting cultivation are altitude, temperature, rainfall, length of day, day light, soil and soil fertility, fertilizers and pests. The effects of these factors have been studied by growing particular plants in different environmental conditions and observing variations. For example,a plant which is subjected to a particular environ-ment may develop as a small plant which, when analysed shows high proportion of metabolite than the plants attained the required growth. Nutrients have the ability to enhance the production of secondary metabolites, at the same time they may reduce the metabolites as well.AltitudeAltitude is a very important factor in cultivation of medicinal plants. Tea, cinchona and eucalyptus are cultivated favour-ably at an altitude of 1,000–2,000 metres. Cinnamon and cardamom are grown at a height of 500–1000 metres, while senna can be cultivated at sea level. The following are the examples of medicinal and aromatic plants indicating the altitude for their successful cultivation (Table 6.1).Chapter-06.indd 72 10/12/2009 4:07:07 PM73CULTIVATION, COLLECTION AND PROCESSING OF HERBAL DRUGSTable 6.1 Altitude for Drug cultivationPlant Altitude (metres)Tea 1,000–1,500Cinchona 1,000–2,000Camphor 1,500–2,000Cinnamon 250–1,000Coffee 1,000–2,000Clove Up to 900Saffron Up to 1,250Cardamom 600–1,600TemperatureTemperature is a crucial factor controlling the growth, metabolism and there by the yield of secondary metabolites of plants. Even though each species has become adapted to its own natural environment, they are able to exist in a considerable range of temperature. Many plants will grow better in temperate regions during summer, but they lack in resistance to withstand frost in winter.Table 6.2 Optimum Temperature for Drug CultivationPlant Optimum Temperature (°F)Cinchona 60–75Coffee 55–70Tea 70–90Cardamom 50–100RainfallFor the proper development of plant, rainfall is required in proper measurements. Xerophytic plants like aloes do not require irrigation or rainfall. The effects of rainfall on plants must be considered in relation to the annual rainfall throughout the year with the water holding properties of the soil. Variable results have been reported for the produc-tion of constituents under different conditions of rainfall. Excessive rainfall could cause a reduction in the secondary metabolites due to leaching of water soluble substances from the plants.Day Length and Day LightIt has been proved that even the length of the day has an effect over the metabolites production. The plants that are kept in long day conditions may contain more or less amount of constituents when compared to the plants kept in short day. For example peppermint has produced menthone, menthol and traces of menthofuran in long day conditions and only menthofuran in short day condition.The developments of plants vary much in both the amount and intensity of the light they require. The wild grown plants would meet the required conditions and so they grow but during cultivation we have to fulfill the requirements of plants. The day light was found to increase the amount of alkaloids in belladonna, stramonium, cin-chona, etc. Even the type of radiation too has an effect over the development and metabolites of plants.SoilEach and every plant species have its own soil and nutri-tive requirements. The three important basic characteristics of soils are their physical, chemical and microbiological properties. Soil provides mechanical support, water and essential foods for the development of plants. Soil consists of air, water, mineral matters and organic matters. Variations in particle size result in different soils ranging from clay, sand and gravel. Particle size influences the water holding capacity of soil. The type and amount of minerals plays a vital role in plant cultivation. Calcium favours the growth of certain plants whereas with some plants it does not produce any effects. The plants are able to determine their own soil pH range for their growth; microbes should be taken in to consideration which grows well in certain pH. Nitrogen containing soil has a great momentum in raising the production of alkaloids in some plants.Depending upon the size of the mineral matter, the following names are given to the soil (Table 6.3).Table 6.3 Type of soil on the basis of particle size.Particle size (diametre) Type of soilLess than 0.002 mm Fine clay0.002–0.02 mm Coarse clay or silt0.02–0.2 mm Fine sand0.2–2.0 mm Coarse sandDepending upon the percentage covered by clay, soils are classified as under (Table 6.4.).Table 6.4 Type of soil on the basis of percentage covered by clay.Type of soil Percentage covered by clayClay More than 50% of clayLoamy 30–50% of claySilt loam 20–30% of claySandy loam 10–20% of claySandy soil More than 70% sandCalcarious soil More than 20% of limeSoil FertilityIt is the capacity of soil to provide nutrients in adequate amounts and in balanced proportion to plants. If cropping Chapter-06.indd 73 10/12/2009 4:07:07 PM74 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYis done without fortification of soil with plant nutrients, soil fertility gets lost. It is also diminished through leaching and erosion. Soil fertility can be maintained by addition of animal manures, nitrogen-fixing bacteria or by application of chemical fertilizers. The latter is time saving and surest of all above techniques.Fertilizers and ManuresPlant also needs food for their growth and development. What plants need basically for their growth are the carbon dioxide, sun-rays, water and mineral matter from the soil. Thus, it is seen that with limited number of chemical elements, plants build up fruits, grains, fibres, etc. and synthesize fixed and volatile oils, glycosides, alkaloids, sugar and many more chemicals.(a) Chemical fertilizersAnimals are in need of vitamins, plants are in need of sixteen nutrient elements for synthesizing various com-pounds. Some of them are known as primary nutrients like nitrogen, phosphorus and potassium. Magnesium, calcium and sulphur are required in small quantities and hence, they are known as secondary nutrients. Trace elements like copper, manganese, iron, boron, molybdenum, zinc are also necessary for plant growths are known as micronutrients. Carbon, hydrogen, oxygen and chlorine are provided from water and air. Every element has to perform some specific function in growth and development of plants. Its deficiency is also characterized by certain symptoms. (b) ManuresFarm yard manure (FYM/compost), castor seed cake, poultry manures, neem and karanj seed cakes vermin compost, etc. are manures. Oil-cake and compost normally consists of 3–6% of nitrogen, 2% phosphates and 1–1.5% potash. They are made easily available to plants. Bone meal, fish meal, biogas slurry, blood meal and press mud are the other forms of organic fertilizers.(c) BiofertilizersInadequate supply, high costs and undesirable effects if used successively are the demerits of fertilizers or manures and hence the cultivator has to opt for some other type of fertilizer. Biofertilizers are the most suitable forms that can be tried. These consist of different types of micro organisms or lower organisms which fix the atmospheric nitrogen in soil and plant can use them for their day to day use. Thus they are symbiotic. Rhizobium, Azotobactor, Azosperillium, Bijericcia, Blue-green algae, Azolla, etc. are the examples of biofertilizers. Pests and Pests ControlPests are undesired plant or animal species that causes a great damage to the plants. There are different types of pests; they are microbes, insects, non insect pests and weeds.MicrobesThey include fungi, bacteria and viruses. Armillaria Root Rot (Oak Root Fungus) is a disease caused by fungi Armil-laria mellea (Marasmiaceae) and in this the infected plant become nonproductive and very frequently dies within two to four years. Plants develop weak, shorter shoots as they are infected by the pathogen. Dark, root-like structures (rhizomorphs), grow into the soil after symptoms develop on plants. The fungus is favoured by soil that is continuallydamp. Powdery mildew is another disease caused by fungus Uncinula necato on leaves, where chlorotic spots appear on the upper surface of leaf. On fruit the pathogen appears as white, powdery masses that may colonize the entire berry surface. Summer Bunch Rot is a disease in which masses of black, brown, or green spores develop on the surface of infected berries caused by a variety microbes like Aspergillus niger, Alternaria tennis, Botrytis cinerea, Cladosporium herbarum, Rhizopus arrhizus, Penicillium sp., and others.Fomitopsis pinicola (Sw.) P. Karst. Belonging to family Fomitopsidaceae causes a diseases known as red-belted fungus. Several other fungi attacks the medicinal plants, like Pythium pinosurn causes pythium rhizome rot, Septoria digitalis causing leaf spot, little leaf disease by Phywphthora cinnamomi Rands (Pythiaceae), etc.Crown gall disease caused by Agrobacterium tumefaciens (Rblzobiaceae). Galls may be produced on canes, trunks, roots, and cordons and may grow to several inches in diameter. Internally galls are soft and have the appearance of disorganized tissue. The pathogen can be transmitted by any agent that contacts the contaminated material. Galls commonly develop where plants have been injured during cultivation or pruning. Xylella fastidiosa is a bacterium causes Pierce’s Disease, in this leaves become slightly yellow or red along margins and eventually leaf margins dry or die.Many viruses are also reported to cause necrosis of leaves, petioles and stems, they are tobacco mosaic virus, mosaic virus, cucumber mosaic virus, tobacco ring spot virus, yellow vein mosaic, etc.Controlling techniques: Chemical fumigation of the soil, fungicide, bactericide, pruning, proper water and fertilizer management, good sanitation, heat treatment of planting stock, cut and remove the infected parts, geneti-cally manipulating the plants for producing plants to resist fungi and bacteria are practices that are used to prevent or minimize the effects produced by microbes.InsectsAnts, they are of different varieties, Argentine ant: Linepi-thema humile, Gray ants: Formica aerata and Formica perpilosa, Pavement ant: Tetramorium caespitum., Southern fire ant: Solenopsis xyloni, Thief ant: Solenopsis molesta, they spoil the soil by making nest and they feed honey dew secreted in plants.Chapter-06.indd 74 10/12/2009 4:07:07 PM75CULTIVATION, COLLECTION AND PROCESSING OF HERBAL DRUGSBranch and Twig Borer (Melalgus confertus) burrow into the canes through the base of the bud or into the crotch formed by the shoot and spur. Feeding is often deep enough to completely conceal the adult in the hole. When shoots reach a length of 10–12 inches, a strong wind can cause the infected parts to twist and break. The click beetle (Limo-nius canus) can feed on buds. Cutworms (Peridroma saucia) (Amathes c-nigrum) (Orthndes rufula) injures the buds and so the buds may not develop. Leafhoppers (Erythroneura elegantuhi) (Erythroneum variabilis) remove the contents of leaf cells, leaving behind empty cells that appear as pale yellow spots.Oak twig pruners (Anelaphiis spp. Linsley) are known as shoot, twig and root insects that affects the above men-tioned parts.Controlling techniques: Tilling the soil will also affects the nesting sites of ants and help to reduce their popula-tions, collection and destruction of eggs, larvae, pupae and adults of insects, trapping the insects, insecticides, creat-ing a situation to compete among males for mating with females, cutworms can be prevented by natural enemies like, predaceous or parasitic insects, mammals, parasitic nematodes, pathogens, birds, and reptiles,Non insect pestsThey are divided in to vertebrates and invertebrates. Ver-tebrates that disrupt the plants are monkeys, rats, birds, squirrels, etc. Non vertebrates are, Webspinning Spider Mites (Tetranychuspacificus) (Eotetranychus willamettei) (Tetrany-chus urticae) causes discoloration in leaves and yellow spots. Nematodes (Meloidogyne incognita) (Xiphinema americanutri) (Criconemella xenoplax) produces giant cell formation, dis-turbs the uptake of nutrients and water, and interferes with plant growth, crabs, snails are the other few invertebrates that causes trouble to the plant.Controlling techniques: Construction of concrete ware houses, traps, biological methods, rodenticides, etc.WeedsWeeds reduce growth and yields of plants by competing for water, nutrients, and sunlight. Weed control enhances the establishment of new plants and improves the growth and yield of established plants. The skilled persons have many weed management tools available to achieve these objectives; however, the methods of using these tools vary from year to year and from place to place.Soil characteristics are important to weed management. Soil texture and organic matter influence the weed species that are present, the number and timing of cultivations required, and the activity of herbicides. Annual species, such as puncturevine, crabgrass, horseweed, and Panicum spp., or perennials like johnsongrass, nutsedge, and bermudagrass are more prevalent on light-textured soil while perenni-als such as curly dock, field bindweed, and dallisgrass are more common on heavier-textured soils. Less preemergent herbicide is required for weed control on sandy, light soils, but residual control may be shorter than on clay or clay loam soils. Use low rates of herbicide on sandy soils or those low in organic matter. Clay soils are slower to dry for effective cultivation than sandy loam soils; thus, more frequent cultivation is practiced on lighter soils than heavy soils.Few common weeds are, Bermudagrass, It is a vigorous spring- and summer-growing perennial. It grows from seed but its extensive system of rhizomes and stolons can also be spread during cultivation, Dallisgrass, It is a common perennial weed that can be highly competi-tive in newly planted plants; in established plants area it competes for soil moisture and nutrients. Dallisgrass seedlings germinate in spring and summer, and form new plants on short rhizomes that developed from the original root system. The other weeds are pigweeds Amaranthus spp. pineapple-weed Chamomilla suaveolens, nightshades Solanum spp., etc.Apart from these, Parasitic and Epiphytic Plants like dodder (Cuscuta spp. L.), mistletoe (Phoradendron spp. Nutt.), American squawroot (Conopholis americana), etc., too affects the growth of plants,Controlling techniques: Use of low rates of herbicides: Herbicides are traditionally discussed as two groups: those that are active against germinating weed seeds (preemergent herbicides) and those that are active on growing plants (postemergent herbicides). Some herbicides have both pre-and postemergent activity. Herbicides vary in their ability to control different weed species.Preemergent herbicides are active in the soil against ger-minating weed seedlings. These herbicides are applied to bare soil and are leached into the soil with rain or irrigation where they affect germinating weed seeds. If herbicides remain on the soil surface without incorporation, some will degrade rapidly from sunlight. Weeds that emerge while the herbicide is on the surface, before it is activated by rain or irrigation, will not be controlled. Postemergent herbicides are applied to control weeds already growing in the vineyard. They can be combined with preemergent herbicides or applied as spot treatments during the growing season. In newly planted plants, selective postemergent herbicides are available for the control of most annual and perennial grasses, but not broadleaf weeds.Frequent wetting of the soil promotes more rapid herbicide degradation in the soil. Herbicide degradation is generally faster in moist, warm soils than in dry, cold soils. Chapter-06.indd 75 10/12/2009 4:07:07 PM76 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYGeneral Methods of Pest ControlsControlling techniques Methods involvedCultural Changing the time of sowing and harvesting, maintenance of storage, special cultivation methods, proper cleaning, Using trap crops and resistant varietiesPhysical Mechanical control Utilization of physical factors (temperature, less oxygen concentration, humidity, passing CO2)Biological Using predators, parasites, pathogens, sterilization, genetic manipulation, pheromonesChemical Use of pesticides, herbicides, antifeedantsOther Factors that Affect the Cultivated PlantsAir PollutionChemical discharges into the atmosphere have increased dramatically during this century, but the total effect on plants is virtually unknown. It has been demonstrated that air pollutants can cause mortality and losses in growth of plants. Nearly all species of deciduous and coniferous trees are sensitive to some pollutants. There are many chemicals released into the atmosphere singly and as compounds. In addition, other compounds are synthesized in the atmo-sphere. Some chemicals can be identified through leaf tissue analysis and by analysing the air. Generally, pollution injury first appears as leaf injury. Spots between the veins, leaf margin discoloration, and tip burns are common. These symptoms can also be influenced by host sensitivity, which is effected by genetic characteristics and environmental factors.HerbicideHerbicides should be handled very carefully; misapplication of herbicides can often damage nontarget plants. The total extent of such damage remains unclear, but localized, severe damage occurs. Symptoms of herbicide injury are variable due to chemical mode of action, dosage, duration of expo-sure, plant species, and environmental conditions. Some herbicides cause growth abnormalities such as cupping or twisting of foliage while others cause foliage yellowing or browning, defoliation, or death.6.5. PLANT HORMONES AND GROWTH REGULATORSPlant hormones (phytohormones) are physiological inter-cellular messengers that control the complete plant lifecycle, including germination, rooting, growth, flowering, fruit ripening, foliage and death. In addition, plant hormones are secreted in response to environmental factors such as excess of nutrients, drought conditions, light, temperature and chemical or physical stress. So, levels of hormones will change over the lifespan of a plant and are dependent upon season and environment.The term ‘plant growth factor’ is usually employed for plant hormones or substances of similar effect that are administered to plants. Growth factors are widely used in industrialized agriculture to improve productivity. The application of growth factors allows synchronization of plant development to occur. For instance, ripening fruits can be controlled by setting desired atmospheric ethylene levels. Using this method, fruits that are separated from their parent plant will still respond to growth factors; allowing commercial plants to be ripened in storage during and after transportation. This way the process of harvesting can be run much more efficiently and effectively. Other applica-tions include rooting of seedlings or the suppression of rooting with the simultaneous promotion of cell division as required by plant cell cultures. Just like with animal hormones, plant growth factors come in a wide variety, producing different and often antagonistic effects. In short, the right combination of hormones is vital to achieve the desired behavioural characteristics of cells and the produc-tive development of plants as a whole. The plant growth regulators are classified into synthetic and native. The synthetic regulators are also known as exogenous regulators and the native are called the endogenous,Five major classes of plant hormones are mentioned: auxins, cytokinins, gibbereilins, abscisic acid and ethylene. However as research progresses, more active molecules are being found and new families of regulators are emerging; one example being polyamines (putrescine or spermidine). Plant growth regulators have made the way for plant tissue culture techniques, which were a real boon for mankind in obtaining therapeutically valuable secondary metabolites.AuxinsCH COOH2HNThe term auxin is derived from the Greek word auxein which means to grow. Generally compounds are considered as auxins if they are able to induce cell elongation in stems and otherwise resemble indoleacetic acid (the first auxin isolated) in physiological activity. Auxins usually affect other processes in addition to cell elongation of stem cells but this characteristic is considered critical of all auxins and thus ‘helps’ define the hormone.Auxins were the first plant hormones discovered. Charles Darwin was among the first scientists to pool in plant Chapter-06.indd 76 10/12/2009 4:07:07 PM77CULTIVATION, COLLECTION AND PROCESSING OF HERBAL DRUGShormone research. He described the effects of light on movement of canary grass coleoptiles in his book ‘The Power of Movement in Plants’ presented in 1880. The coleoptile is a specialized leaf originating from the first node which sheaths the epicotyl in the plants seedling stage protecting it until it emerges from the ground. When unidirectional light shines on the coleoptile, it bends in the direction of the light. If the tip of the coleoptile was covered with aluminium foil, bending would not occur towards the unidirectional light. However if the tip of the coleoptile was left uncovered but the portion just below the tip was covered, exposure to unidirectional light resulted in curvature toward the light. Darwin’s experiment suggested that the tip of the coleoptile was the tissue responsible for perceiving the light and producing some signal which was transported to the lower part of the coleoptile where the physiological response of bending occurred. When he cut off the tip of the coleoptile and exposed the rest of the coleoptile to unidirectional light curvature did not occur confirming the results of his experiment.Salkowski (1885) discovered indole-3-acetic acid (IAA) in fermentation media. The isolation of the same product from plant tissues would not be found in plant tissues for almost 50 years. IAA is the major auxin involved in many of the physiological processes in plants. Fitting in 1907 put his efforts in studying signal transaction by making incisions on the light or dark side of the plant. He failed because the signal was capable of crossing or going around the incision, In 1913, modification was made in Fitting’s experiment by Boysen-Jensen, in that they inserted pieces of mica to block the transport of the signal and showed that transport of auxin toward the base occurs on the dark side of the plant as opposed to the side exposed to the unidirectional light. In 1918, Paal confirmed Boysen-Jensen’s results by cutting off coleoptile tips in the dark, exposing only the tips to the light, replacing the coleoptile tips on the plant but off centered to one side or the other. Results showed that whichever side was exposed to the coleoptile, curvature occurred toward the other side. Soding 1925, followed Paal’s idea and showed that if tips were cut off there was a reduction in growth but if they were cut off and then replaced growth continued to occur.In 1926, Fritz Went reported a plant growth substance, isolated by placing agar blocks under coleoptile tips for a period of time then removing them and placing them on decapitated Avena stems. After placement over the agar, the stems resumed growth. In 1928, again Went developed a method of quantifying this plant growth substance. His results suggested that the curvatures of stems were proportional to the amount of growth substance in the agar. This test was called the avena curvature test. Much of our current knowledge of auxin was obtained from its applications. It wasWent’s work, which had a great influence in stimulating plant growth substance research. He is often credited with dubbing the term auxin but it was actually Kogl and Haagen-Smit who purified the compound auxentriolic acid (auxin A) from human urine in 1931. Later Kogl isolated other compounds from urine which were similar in structure and function to auxin A. One of which was indole-3 acetic acid (IAA) initially discovered by Salkowski in 1885. In 1954 a committee of plant physiologists was set up to characterize the group auxins.Indole acetic acid (IAA) is the principle natural auxin and other natural auxins are indole-3-acetonitrile (IAN), phenyl acetic acid and 4-chloroindole-3-acetic acid. The exogenous or synthetic auxins are indole-3-butyric acid (IBA), α-napthyl acetic acid (NAA), 2-napthyloxyacetic acid (NOA), 1-napthyl acetamide (NAD), 5-carboxymeth-yl-N, N-dimethyl dithiocarbamate, 2,4-dichlorophenoxy acetic acid (2,4-D), etc.CH COOH2HNIAACH COOH2NAACh COOH2CH CH2 2HNIBACH CONH2NADO-CH COOH2NOA2,4-DO-CH COOH2CICIChapter-06.indd 77 10/12/2009 4:07:08 PM78 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYProduction and occurrenceProduced in shoot and root meristematic tissue, in young leaves, mature root cells and small amounts in mature leaves. Transported throughout the plant parts and the production of IAA will be more in day time. It is released by all cells when they are experiencing conditions which would normally cause a shoot meristematic cell to produce auxin. Ethylene has direct or indirect action over to enhance the synthesis auxin.IAA is chemically similar to the amino acid tryptophan which is generally accepted to be the molecule from which IAA is derived. Three mechanisms have been suggested to explain this conversion:Tr � yptophan is converted to indolepyruvic acid through a transamination reaction. Indolepyruvic acid is then converted to indoleacetaldehyde by a decarboxylation reaction. The final step involves oxidation of indoleac-etaldehyde resulting in indoteacetic acid.Tryptophan undergoes decarboxylation resulting in �tryptamine. Tryptamine is then oxidized and deaminated to produce indoleacetaldehyde. This molecule is further oxidized to produce indoleacetic acid.IAA can be produced via a tryptophan-independent �mechanism. This mechanism is poorly understood, but has been proven using tip (-) mutants. Other experiments have shown that, in some plants, this mechanism is actu-ally the preferred mechanism of IAA biosynthesis.Fig. 6.1 Pathways of IAA biosynthesisFrom the shikimic acid pathwayNHCH -C N2 � CH CH NH22 2NHNHNHCH -C-COOH2OIndole-3-glycerolphosphateOHCCOHCHOHCHO PO4NHTryptophanCH CH(NH )COOH2 2NHIndoneNHIndoleacetonitrile Indoleacetaldoxime Indolepyruvuc acidHCH -C=N - OH2TryptamineNHCH -C-CH2OIndoleacetaldehydeIndoleacetic acid(IAA)Iindolebutyric acid(IBA)NHNHCH -COOH2CH CH CH -COOH2 2 2Tryptophanindependentpathways?Chapter-06.indd 78 10/14/2009 1:30:15 PM79CULTIVATION, COLLECTION AND PROCESSING OF HERBAL DRUGSThe enzymes responsible for the biosynthesis of IAA are most active in young tissues such as shoot apical mer-istems and growing leaves and fruits. These are the same tissues where the highest concentrations of IAA are found. One way plants can control the amount of IAA present in tissues at a particular time is by controlling the biosynthesis of the hormone. Another control mechanism involves the production of conjugates which are, in simple terms, mol-ecules which resemble the hormone but are inactive. The formation of conjugates may be a mechanism of storing and transporting the active hormone. Conjugates can be formed from IAA via hydrolase enzymes. Conjugates can be rapidly activated by environmental stimuli signaling a quick hormonal response. Degradation of auxin is the final method of controlling auxin levels. This process also has two proposed mechanisms outlined below:The oxidation of IAA by oxygen resulting in the loss of the carboxyl group and 3-methyleneoxindole as the major breakdown product. IAA oxidase is the enzyme which catal-yses this activity. Conjugates of IAA and synthetic auxins such as 2,4-D can not be destroyed by this activity.C-2 of the heterocyclic ring may be oxidized resulting in oxindole-3-acetic acid. C-3 may be oxidized in addition to C-2 resulting in dioxindole-3-acetic acid. The mechanisms by which biosynthesis and degradation of auxin molecules occur are important to future agricultural applications. Information regarding auxin metabolism will most likely lead to genetic and chemical manipulation of endogenous hormone levels resulting in desirable growth and differ-entiation of important plant species.Functions of auxinSt � imulates cell elongation. The auxin supply from the apical bud suppresses growth �of lateral buds. Apical dominance is the inhibiting influ-ence of the shoot apex on the growth of axillary buds. Removal of the apical bud results in growth of the axillary buds. Replacing the apical bud with a lanolin paste containing IAA restores the apical dominance. The mechanism involves another hormone - ethylene. Auxin (IAA) causes lateral buds to make ethylene, which inhibits growth of the lateral buds. Differentiation of vascular tissue (xylem and phloem) �is stimulated by IAA. Auxin stimulates root initiation on stem cuttings and �lateral root development in tissue culture (adventitious rooting). Auxin mediates the tropistic response of bending in �response to gravity and light (this is how auxin was first discovered). Auxin has various effects on leaf and fruit abscission, �fruit set, development, and ripening, and flowering, depending on the circumstances.CytokininsCytokinins are compounds with a structure resembling adenine which promote cell division and have other similar functions to kinetin. They also regulate the pattern and frequency of organ production as well as position and shape. They have an inhibitory effect on senescence. Kinetin was the first cytokinin identified and so named because of the compounds ability to promote cytokinesis (cell division). Though it is a natural compound, it is not made in plants, and is therefore usually considered a ‘synthetic’ cytokinin. The common naturally occurring cytokinin in plants today is called zeatin which was isolated from corn.Cytokinin have been found in almost all higher plants as well as mosses, fungi, bacteria, and also in many prokary-otes and eukaryotes. There are more than 200 natural and synthetic cytokinins identified. Cytokinin concentrations are more in meristematic regions and areas of continuous growth potential such as roots, young leaves, developing fruits, and seeds.Haberlandt (1913) and Jablonski and Skoog (1954) identified that a compound found in vascular tissues had the ability to stimulate cell division. In 1941, Johannes van Overbeek discovered that the milky endosperm from coconut and other various species of plants also had this ability. The first cytokinin was isolated from herring sperm in 1955 by Miller and his associates. This compound was named kinetin because of its ability to promote cytokine-sis (cell division). The first naturally occurring cytokinin was isolated from corn in 1961 by Miller and it was later called zeatin. Since that time, many more naturally occur-ring cytokinins have been isolated and the compound was common to all plant species in one form or another.The naturally occurring cytokinins are zeatin, N6 dim-ethyl amino purine, isopentanyl aminopurine. The syn-thetic cytokinins are kineatin, adenine, 6-benzyl adenine benzimidazole and N, N’-diphenyl urea.NN NHNONH—CH2KinetinNN NHNNH—CH2—CH CZeatinCH3CH3OHProduction and occurrenceProduced in root and shoot meristematic tissue,in mature shoot cells and in mature roots in small amounts. If is rapidly transported in xylem stream. Peak production occurs in day time and their activity is reduced in plants suffering drought. It is directly or indirectly induced by high levels of Gibberlic acid.Cytokinin is generally found in meristematic regions and growing tissues. They are believed to be synthesized in the Chapter-06.indd 79 10/12/2009 4:07:08 PM80 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYroots and translocated via the xylem to shoots. Cytokinin biosynthesis happens through the biochemical modification of adenine. They are synthesized by following pathway.A product of the mevalonate pathway called isopentyl pyrophosphate is isomerized. This isomer can then react with adenosine monophosphate with the aid of an enzyme called isopentenyl AMP synthase. The result is isopentenyl adenosine-5’-phosphate (isopentenyl AMP). This product can then be converted to isopentenyl adenosine by removal of the phosphate by a phosphatase and further converted to isopentenyl adenine by removal of the ribose group. Isopentenyl adenine can be converted to the three major forms of naturally occurring cytokinins.Other pathways or slight alterations of this one probably lead to the other forms. Degradation of cytokinins occurs largely due to the enzyme cytokinin oxidase. This enzyme removes the side chain and releases adenine. Derivatives can also be made but the difficulties are with pathways, which are more complex and poorly understood.Functions of cytokininStimulate cell division (cytokinesis). �Stimulate morphogenesis (shoot initiation/bud forma- �tion) in tissue culture.Stimulate the growth of lateral (or adventitious) buds- �release of apical dominance.Stimulate leaf expansion resulting from cell enlarge- �ment.May enhance stomatal opening in some species �(Figure 6.2).Promotes the conversion of etioplasts into chloroplasts �via stimulation of chlorophyll synthesis.Stimulate the dark-germination of light-dependent �seeds.Delays senescence. �Promotes some stages of root development. �(a) (b)Fig. 6.2 Effect of cytokinin on stomatal openingEthyleneHHC CHHEthyleneEthylene has been used in practice since the ancient times, where people would use gas figs in order to stimulate ripen-ing, burn incense in closed rooms to enhance the ripening of pears. It was in 1864, that leaks of gas from street lights showed stunting of growth, twisting of plants, and abnormal thickening of stems. In 1901, a Russian scientist named Dimitry Neljubow showed that the active component was ethylene. Doubt 1917, discovered that ethylene stimulated abscission. In 1932 it was demonstrated that the ethylene evolved from stored apple inhibited the growth of potato shoots enclosed with them. In 1934 Gane reported that plants synthesize ethylene. In 1935, Crocker proposed that ethylene was the plant hormone responsible for fruit ripening as well as inhibition of vegetative tissues. Ethylene is now known to have many other functions as well.Production and occurrenceProduction is directly induced by high levels of Auxin, root flooding and drought. It is found in germinating seeds and produced in nodes of stems, tissues of ripening fruits, response to shoot environmental, pest, or disease stress and in senescent leaves and flowers. Light minimizes the production of ethylene. It is released by all cells when they are experiencing conditions which would normally cause a mature shoot cell to produce ethylene.Ethylene is produced in all higher plants and is produced from methionine in essentially all tissues. Production of ethylene varies with the type of tissue, the plant species, and also the stage of development. The mechanism by which ethylene is produced from methionine is a three step process. ATP is an essential component in the synthesis of ethylene from methionine. ATP and water are added to methionine resulting in loss of the three phosphates and S-adenosyl methionine (SAM). 1-amino-cyclopropane-l-carboxylic acid synthase (ACC-synthase) facilitates the production of ACC from SAM. Oxygen is then needed in order to oxidize ACC and produce ethylene. This reaction is catalysed by an oxidative enzyme called ethylene forming enzyme. The control of ethylene production has received considerable study. Study of ethylene has focused around the synthesis promoting effects of auxin, wounding, and drought as well as aspects of fruit-ripening. ACC synthase is the rate limiting step for ethylene production and it is this enzyme that is manipulated in biotechnology to delay fruit ripening in the ‘flavor saver’ tomatoes.Functions of ethyleneProduction stimulated during ripening, flooding, stress, �senescence, mechanical damage, infection.Regulator of cell death programs in plants (apoptosis). �Stimulates the release of dormancy. �Stimulates shoot and root growth and differentiation �(triple response).Regulates ripening of climacteric fruits. �May have a role in adventitious root formation. �Stimulates leaf and fruit abscission. �Flowering in most plants is inhibited by ethylene. �Mangos, pineapples and some ornamentals are stimu-lated by ethylene.Chapter-06.indd 80 10/12/2009 4:07:08 PM81CULTIVATION, COLLECTION AND PROCESSING OF HERBAL DRUGSInduction of femaleness in dioecious flowers. �Stimulates flower opening. �Stimulates flower and leaf senescence. �GibberellinsOOCHOCH3COOHOHCH2Gibberellic acidUnlike the classification of auxins which are classified on the basis of function, gibberellins are classified on the basis of structure as well as function. All gibberellins are derived from the ent-gibberellane skeleton. The gibberellins are named GA1. GAn in order of discovery. Gibberellic acid was the first gibberellin to be structurally characterized as GA3. There are currently 136 GAs identified from plants, fungi and bacteria.They are a group of diterpenoid acids that functions as plant growth regulators influencing a range of developmen-tal processes in higher plants including stem elongation, germination, dormancy, flowering, sex expression, enzyme induction and leaf and fruit senescence. The origin of research into gibberellins can be traced to Japanese plant pathologists who were investigating the causes of the ‘bakanae’ (foolish seedling) disease which seriously lowered the yield of rice crops in Japan, Taiwan and throughout the Asian countries. Symptoms of the disease are pale yellow, elongated seedlings with slender leaves and stunted roots. Severely diseased plants die whereas plants with slight symptoms survive but produce poorly developed grain, or none at all.Bakanae is now easily prevented by treatment of seeds with fungicides prior to sowing. In 1898 Shotaro Hori demonstrated that the symptoms were induced by infection with a fungus belonging to the genus Fusarium, probably Fusarium heterosporium Necs.In 1912, Sawada suggested that the elongation in rice-seedlings infected with bakanae fungus might be due to a stimulus derived from fungal hyphae.Subsequently, Eiichi Kurosawa (1926) found that culture filtrates from dried rice seedlings caused marked elongation in rice and other sub-tropical grasses. He concluded that bakanae fungus secretes a chemical that stimulates shoot elongation, inhibits chlorophyll formation and suppresses root growth.Although there has been controversy among plant pathologists over the nomenclature of bakanae fungus, in the 1930s, the imperfect stage of the fungus was named Fusarium moniliforme (Sheldon) and the perfect stage, was named as Gibberella fujikuroi (Saw.) Wr. by H.W. Wol-lenweber. The terms ‘Fujikuroi’ and ‘Saw’ in Gibberella fujikuroi (Saw.) Wr. were derived from the names of two distinguished Japanese plant pathologists, Yosaburo Fujikuro and Kenkichi Sawada.In 1934, Yabuta isolated a crystallinecannot have their action without satisfying the positions at C3, C1, C8, C9 and C10.Drugs obtained by partial synthesis of natural productsOxytocic activity of methyl ergometrine is more than that of ergometrine. In ergotamine, by 9:10 hydrogenation, oxytocic activity is suppressed and spasmolytic activity increases. We have already referred to the preparation of steroid hormones from diosgenin by acetolysis and oxi-dation and further preparation of cortisone by microbial reactions. Steroid hormones and their semisynthetic analogues represent a multimillion dollar industry in the United States.Natural products as models for synthesis of new drugsMorphine is the model of a large group of potent analgesics, cocaine for local anaesthetics, atropine for certain spasmo-lytics, dicoumarol for anticoagulants and salicin for salicylic acid derivatives. Without model substances from plants a large number of synthetics would have been missed.Drugs of direct therapeutic usesAmong the natural constituents, which even now cannot be replaced, are important groups of antibiotics, steroids, ergot alkaloids and certain antitumour substances. Further, drugs as digitoxin, strophanthus glycosides, morphine, atropine and several others are known since long and have survived their later day synthetic analogues.Biosynthetic pathwaysBiosynthetic pathways are of primary and secondary metab-olites. Some of the important pathways are Calvin’s cycle of photosynthesis, shikimic acid pathway of aromatic com-pounds, acetate hypothesis for anthracene glycosides and isoprenoid hypothesis for terpenes and steroids via acetate-mevalonic acid-isopentyl pyrophosphate and squalene.Progress from 1960 onwardsDuring this period only a few active constituents mainly antibiotics, hormones and antitumour drugs were isolated or new possibilities for their production were found. From 6-amino penicillanic acid, which has very little antibiotic action of its own, important broad-spectrum semisyn-thetic penicillins like ampenicillin and amoxicillin were developed. From ergocryptine, an alkaloid of ergot, bromocryptine has been synthesized. Bromocryptine is a prolactin inhibitor and also has activity in Parkinson’s disease and in cancer. By applications of several disciplines, pharmacognosy from a descriptive subject has again developed into an integral and important disciplines of pharmaceutical sciences.Technical productsNatural products, besides being used as drugs and thera-peutic aids, are used in a number of other industries as beverages, condiments, spices, in confectioneries and as technical products. The coffee beans and tea leaves besides being the source of caffein are used as popular beverages. Ginger and win-tergreen oil are used less pharmaceutically but are more used in preparation of soft drinks. Mustard seed and clove are used in spice and in condiment industry. Cinnamon oil and peppermint oil besides being used as carminatives are used as flavouring agents in candies and chewing gum. Colophony resin, turpentine oil, linseed oil, acacia, pectin, and numerous other natural products are used widely in other industries and are called technical products. Chapter-01.indd 6 10/12/2009 3:47:10 PM7HISTORY, DEFINITION AND SCOPE OF PHARMACOGNOSYPharmaceuticals aidsSome of the natural products obtained from plants and animals are used as pharmaceutical aids. Thus gums like acacia and tragacanth are used as binding, suspending and emulsifying agents. Guar gum is used as a thickening agent and as a binder and a disintegrating agent in the manufacturing of tablets. Sterculia and tragacanth because of their swelling property are used as bulk laxative drugs. Mucilage-containing drugs like ishabgul and linseed are used as demulcents or as soothing agents and as bulk laxatives. Starch is used as a disintegrating agent in the manufacture of tablets and because of its demulcent and absorbent properties it’s used in dusting powders. Sodium alginate is used as an establishing, thickening, emulsifying deflocculating, gelling and filming agent. Carbohydrate-containing drugs like glucose, sucrose and honey are used as sweetening agents and as laxative by osmosis. Agar, in addition to being used as a laxative by osmosis, is also used as an emulsifying agent and in culture media in microbiology. Saponins and sponin-containing drugs are used as detergents, emulsifying and frothing agents and as fire extinguishers. Tincture quillaia is used in preparation of coal tar emulsions. Saponins are toxic and their internal use requires great care, and in some countries their internal use as frothing agents is restricted. Glycyrrhiza is used as sweetening agent for masking the taste of bitter and salty preparations. Fixed oils and fats are used as emollients and as oint-ment bases and vehicles for other drugs. Volatile oils are used as flavouring agents. Gelatin is used in coating of pills and tablets and in preparation of suppositories, as culture media in microbiol-ogy and in preparation of artificial blood plasma. Animal fats like lard and suet are used as ointment bases. Beeswax is used as ointment base and thickening agent in oint-ments. Wool fat and wool alcohols are used as absorbable ointment bases. Thus, from the above description it can be seen that many of the natural products have applications as phar-maceutical aids.Discovery of new medicines from plants—nutraceutical use versus drug development Little work was carried out by the pharmaceutical indus-try during 1950–1980s; however, during the 1980–1990s, massive growth has occurred. This has resulted in new developments in the area of combinatorial chemistry, new advances in the analysis and assaying of plant materials and a heightened awareness of the potential plant materials as drug leads by conservationists. New plant drug develop-ment programmes are traditionally undertaken by either random screening or an ethnobotanical approach, a method based on the historical medicinal/food use of the plant. One reason why there has been resurgence in this area is that conservationists especially in the United States have argued that by finding new drug leads from the rainfor-est, the value of the rainforests to society is proven, and that this would prevent these areas being cut down for unsustainable timber use. However, tropical forests have produced only 47 major pharmaceutical drugs of world-wide importance. It is estimated that a lot more, say about 300 potential drugs of major importance may need to be discovered. These new drugs would be worth $147 billion. It is thought that 125,000 flowering plant species are of pharmacological relevance in the tropical forests. It takes 50,000 to 100,000 screening tests to discover one profitable drug. Even in developed countries there is a huge potential for the development of nutraceuticals and pharmaceuticals from herbal materials. For example the UK herbal materia medica contains around 300 species, whereas the Chinese herbal materia medica contains around 7,000 species. One can imagine what lies in store in the flora-rich India!1.4. SCOPE OF PHARMACOGNOSYCrude drugs of natural origin that is obtained from plants, animals and mineral sources and their active chemical constituents are the core subject matter of pharmacognosy. These are also used for the treatment of various diseases besides being used in cosmetic, textile and food industries. During the first half of the nineteenth century apothecaries stocked the crude drugs for the preparation of herbal tea mixtures, all kinds of tinctures, extracts and juices which in turn were employed in preparing medicinal drops, syrups, infusions, ointments and liniments.The second half of the nineteenth century brought with it a number of important discoveries in the newly developing fields of chemistry and witnessed the rapid progress of this science.compound from the fungal culture filtrate that inhibited growth of rice seedlings at all concentrations tested. The structure of the inhibitor was found to be 5-n-butylpicolinic acid or fusaric acid. The formation of fusaric acid in culture filtrates was suppressed by changing the composition of the culture medium. As a result, a noncrystalline solid was obtained from the culture filtrate that stimulated the growth of rice seedlings. This compound was named gibberellin by Yabuta.In 1938, Yabuta and his associate Yusuke Sumiki finally succeeded in crystallizing a pale yellow solid to yield gib-berellin A and gibberellin B (The names were subsequently interchanged in 1941 and the original gibberellin A was found to be inactive.) Determination of the structure of the active gibberellin was hampered by a shortage of pure crystalline sample. In the United States, the first research on gibberellins began after the Second World War. In 1950, John E. Mitchell reported optimal fermentation procedures for the fungus, as well as the effects of fungal extracts on the growth of bean (Vicia faba) seedlings. In Northern USDA Regional Research Laboratories in Peoria, large scale fermentations were carried out with the purpose of producing pure gibberellin A for agricultural uses but initial fermentations were found to be inactive. Further researches were carried out by Sumiki in 1951, Stodola et al., 1955, Curtis and Cross, 1954 regarding gibberellins and finally the gibberllic acid was determined by its chemical and physical properties.In 1955, members of Sumuki group, succeeded in sepa-rating the methyl ester of gibberellin A into three compo-nents, from which corresponding free acids were obtained and named gibberellins Al, A2, and A3. Gibberellin A3 was found to be identical to gibberellic acid. In 1957, Takahashi et al. isolated a new gibberellin named gibberellin A4 as a minor component from the culture filtrate.In the mid 1950s, evidence that gibberellins were natu-rally occurring substances in higher plants began to appear in the literature. Margaret Radley in the UK demonstrated the presence of gibberellin-like substances in higher plants. In the United States, Bernard Phinney et al were the first to report gibberellin-like substance in maize. This was followed by the isolation of crystalline gibberellin Al, A5, A6 and A8 from runner bean (Phaseotus multiflorus). After 10 years the number of gibberellins reported in the literature isolated from fungal and plant origins rapidly increased. In 1968, J. MacMillan and N. Takahashi concluded that all gibberellins should be assigned numbers as gibberellin A1-x, irrespec-tive of their origin. Over the past 20 years using modern analytical techniques many more gibberellins have been Chapter-06.indd 81 10/12/2009 4:07:08 PM82 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYidentified. At the present time the number of gibberellins identified is 126.Production and occurrenceProduced in the roots, embryo and germinating seeds. The level of gibberellins goes up in the dark when sugar cannot be manufactured and will be reduced in the light. It is released in mature cells (particularly root) when they do not have enough sugar and oxygen to support both themselves and released by all cells when they are experi-encing conditions which would normally cause a mature root cell to produce GA.Gibberellins are diterpenes synthesized from acetyl CoA via the mevalonic acid pathway. They all have either 19 or 20 carbon units grouped into either four or five ring systems. The fifth ring is a lactone ring as shown in the structures above attached to ring A. Gibberellins are believed to be synthesized in young tissues of the shoot and also the developing seed. It is not clear whether young root tissues also produce gibberellins. There is also some evidence that leaves may also contain them. The gibberellins are formed through the pathway, three acetyl CoA molecules are oxi-dized by two NADPH molecules to produce three CoA molecules as a side product and mevalonic acid. Mevalonic acid is then Phosphorylated by ATP and decarboxylated to form isopentyl pyrophosphate. Four of these molecules form geranylgeranyl pyrophosphate which serves as the donor for all GA carbon atoms.This compound is then converted to copalylpyrophos-phate which has 2 ring systems. Copalylpyrophosphate is then converted to kaurene which has 4-ring systems. Sub-sequent oxidations reveal kaurenol (alcohol form), kaurenal (aldehyde form), and kaurenoic acid respectively.Kaurenoic acid is converted to the aldehyde form of GA12 by decarboxylation. GA12 is the first true gibberellane ring system with 20 carbons. From the aldehyde form of GA12 arise both 20 and 19 carbon gibberellins but there are many mechanisms by which these other compounds arise. During active growth, the plant will metabolize most gibberellins by hydroxylation to inactive conjugates quickly with, the exception of GA3. GA3 is degraded much slower which helps to explain why the symptoms initially associ-ated with the hormone in the disease bakanae are present. Inactive conjugates might be stored or translocated via the phloem and xylem before their release (activation) at the proper time and in the proper tissue.Functions of gibberellinsStimulates stem elongation by stimulating cell division �and elongation. GA controls internode elongation in the mature regions of plants. Dwarf plants do not make enough active forms of GA.Flowering in biennial plants is controlled by GA. Bien- �nials grow one year as a rosette and after the winter, they bolt (rapid expansion of internodes and formation of flowers).Breaks seed dormancy in some plants that require strati- �fication or light to induce germination.Stimulates � α-amylase production in germinating cereal grains for mobilization of seed reserves.Juvenility refers to the different stages that plants may �exist in. GA may help determine whether a particular plant part is juvenile or adult.Stimulates germination of pollen and growth of pollen �tubes.Induces maleness in dioecious flowers (sex expres- �sion).Can cause parthenocarpic (seedless) fruit development �or increase the size of seedless fruit (grapes).Can delay senescence in leaves and citrus fruits. �May be involved in phytochrome responses. �Abscisic AcidNatural growth inhibiting substances are present in plants and affect the normal physiological process of them. One such compound is abscisic acid, a single compound unlike the auxins, gibberellins, and cytokinins. It was called ‘absci-sin II’ originally because it was thought to play a major role in abscission of fruits. At about the same time another group was calling it ‘dormin’ because they thought it had a major role in bud dormancy. Though abscisic acid gener-ally is thought to play mostly inhibitory roles, it has many promoting functions as well.H C3 CH3OHCH3HCCHCCH3CHCOOHAbscisic acid (Abscisin II)OIn 1963, when Frederick Addicott and his associates were the one to identify abscisic acid. Two compounds were isolated and named as abscisin I and abscisin II. Abscisin II is presently called abscisic acid (ABA). At the same time Philip Wareing, who was studying bud dormancy in woody plants and Van Steveninck, who was studying abscission of flowers and fruits discovered the same compound.Production and occurrenceABA is a naturally occurring sesquiterpenoid (15-carbon) compound in plants, which is partially produced via the mevalonic pathway in chloroplasts and other plastids. Because it is synthesized partially in the chloroplasts, it makes sense that biosynthesis primarily occurs in the leaves. The production of ABA is by stresses such as water loss and freezing temperatures. The biosynthesis occurs indi-rectly through the production of carotenoids. Breakdown of these carotenoids occurs by the followingmechanism: Chapter-06.indd 82 10/12/2009 4:07:08 PM83CULTIVATION, COLLECTION AND PROCESSING OF HERBAL DRUGSViolaxanthin (forty carbons) is isomerized and then splitted via an isomerase reaction followed by an oxidation reaction. One molecule of xanthonin is produced from one molecule of violaxanthonin and it is not clear what happens to the remaining byproducts. The one molecule of xanthonin produced is unstable and spontaneously changed to ABA aldehyde. Further oxidation results in ABA. Activation of the molecule can occur by two methods. In the first, method, an ABA-glucose ester can form by attachment of glucose to ABA. In the second method, oxidation of ABA can occur to form phaseic acid and dihyhdrophaseic acid. Both xylem and phloem tissues carries ABA. It can also be translocated through parenchyma cells. Unlike auxins, ABA is capable of moving both up and down the stem.Functions of abscisic acidThe abscisic acid stimulates the closure of stomata �(water stress brings about an increase in ABA synthesis) (Figure 6.3).Involved in abscission of buds, leaves, petals, flowers, �and fruits in many, if not all, instances, as well as in dehiscence of fruits.Production is accentuated by stresses such as water loss �and freezing temperatures.Involved in bud dormancy. �Prolongs seed dormancy and delays germination �(vivipary).Inhibits elongation. �ABA is implicated in the control of elongation, lateral �root development, and geotropism, as well as in water uptake and ion transport by roots.ABA coming from the plastids promotes the metabolism �of ripening.Promotes senescence. �Can reverse the effects of growth stimulating hor- �mones.NormalconditionspH 6.3Water stresspH 7.2VeinABALower epidermisGuard cellsMesophyllABAHXylemPhloemABAFig. 6.3 Closure of stomata and water stress brings about an increase in ABA synthesisPolyaminesPolyamines are unique as they are effective in relatively high concentrations. Typical concentrations range from 5 to 500 mg/L. Polyamines influence flowering and promote plant regeneration. Few examples are Spermine, Spermidine and Putrescine. They play a major role in basic genetic processes such as DNA synthesis and gene expression. Spermine and spermidine bind to the phosphate backbone of nucleic acids. The interaction is mostly based on electro-static interactions between negatively charged phosphates of the nucleic acids and the positively charged ammonium groups of the polyamines.Polyamines are responsible for cell migration, prolifera-tion and differentiation in plants. They represent a group of plant growth hormones, but they also have an effect on skin, hair growth, female fertility, fat depots, pancreatic integrity and regenerative growth in mammals. In addition, spermine is an important reagent widely used to precipi-tate DNA in molecular biology protocols. Spermidine is a standard reagent in PCR applications.Spermine and spermidine are derivatives of putrescine (1,4-diaminobutane) which is produced from L-ornithine by action of ODC (ornithine decarboxylase). L-ornithine is the product of L-arginine degradation by arginase. Sper-midine is a triamine structure that is produced by sper-midine synthase (SpdS) which catalyses monoalkylation of putrescine (1,4-diaminobutane) with decarboxylated S-adenosylmethionine (dcAdoMet) 3-aminopropyl donor. The formal alkylation of both amino groups of putrescine with the 3-aminopropyl donor yields the symmetrical tetraamine spermine.BrassinosteroidsThere are approximately 60 naturally occurring polyhydroxy steroids known as brassinosteroids (BRs). They are named after the first one identified, brassinolide, which was isolated from rape in 1979. They appear to be widely distributed in the plant kingdom.In the early 1980s USDA scientists showed that BR could increase yields of radishes, lettuce, beans, peppers and potatoes. However, subsequent results under field condi-tions were disappointing because inconsistent results were obtained. For this reason testing was phased out in the United States. More recently large-scale field trials in China and Japan over a six-year period have shown that 24-epibrassin-olide, an alternative to brassinolide, increased the production of agronomic and horticultural crops (including wheat, corn, tobacco, watermelon, and cucumber). However, once again depending on cultural conditions, method of application, and other factors, the results sometimes were striking while other times they were marginal. Further improvements in the formulation, application method, timing, effects of environmental conditions, and other factors need to Chapter-06.indd 83 10/12/2009 4:07:08 PM84 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYbe investigated further in order to identify the reason for these variable results.Brassinosteroids may be a new class of plant growth substances. They are widely distributed within the plant kingdom, they have an effect at extremely low concentra-tions, both in bioassays and whole plants, and they have a range of effects that are different from the other classes of plant substances. Finally, they can be applied to one part of the plant and transported to another location where, in very low amounts, they elicit a biological response.Functions of brassinosteroidsPromote shoot elongation at low concentrations. �Strongly inhibit root growth and development. �Promote ethylene biosynthesis and epinasty. �Interfere with ecdysteroids (moulting hormones) in �insects. Have had contradictory effects in tissue culture. 24-epi- �brassinolide has been shown to mimic culture condition-ing factors and to be synergistic with these factors in promoting carrot cell growth. However, in transformed tobacco cells brassinosteroids in low concentrations significantly inhibited cell growth.Enhance xylem differentiation. �Decrease fruit abortion and drop. �Enhance resistance to chilling, disease, herbicide, and �salt stress. Promotion of germination. �Promote changes in plasmalemma energization and �transport, assimilate uptake. Increase RNA and DNA polymerase activities and �synthesis of RNA, DNA, and protein.Salicylic AcidSalicylic acid has been known to be present in some plant tissues for quite some time, but has only recently been recognized as a potential PGR. Salicylic acid is synthe-sized from the amino acid phenylalanine. SA is thought by some to be a new class of plant growth regulator. It is a chemically characterized compound, ubiquitously found in the plant kingdom and has an effect on many physi-ological processes in plants at low concentrations. Further molecular studies on SA signal transduction should yield insights into the mechanism of action of this important regulatory compound.Functions of salicylic acidPromotes flowering. �Stimulates thermogenesis in � Arum flowers.Stimulates plant pathogenesis protein production �(systemic acquired resistance). May enhance longevity of flowers. �May inhibit ethylene biosynthesis. �May inhibit seed germination. �Blocks the wound response. �Reverses the effects of ABA. �JasmonatesJasmonates are represented by jasmonic acid and its methyl ester. They were first isolated from the jasmine plant in which the methyl ester is an important product in the perfume industry. Jasmonic acid is synthesized from lino-lenic acid, which is an important fatty acid. Jasmonic acid is considered by some to be a new class of plant growth regulator. It is a chemically characterized compound and has been identified in many plant species. It has physiological effects at very low concentrations and indirect evidence suggests that it is transported throughout the plant.Functions of jasmonatesInhibition of many processes such as seedling longitu- �dinal growth, root length growth, mycorrhizial fungi growth, tissue culture growth,embryogenesis, seed germination, pollen germination, flower bud formation, carotenoid biosynthesis, chlorophyll formation, rubisco biosynthesis, and photosynthetic activitiesPromotion of senescence, abscission, tuber formation, �fruit ripening, pigment formation, tendril coiling, dif-ferentiation in plant tissue culture, adventitious root formation, breaking of seed dormancy, pollen germi-nation, stomatal closure, microtubule disruption, chlo-rophyll degradation, respiration, ethylene biosynthesis, and protein synthesisThey play an important role in plant defense by inducing �proteinase synthesis.6.6. COLLECTION OF CRUDE DRUGSCollection is the most important step which comes after cultivation. Drugs are collected from wild or cultivated plants and the tasks for collection depends upon the col-lector, whether he is a skilled or unskilled labour. Drugs should be collected when they contain maximum amount of constituents in a highly scientific manner. The season at which each drug is collected is so important, as the amount, and sometimes the nature, of the active constituents could be changed throughout the year. For example, Rhubarb is collected only in summer seasons because no anthraqui-none derivatives would be present in winter season but anthranols are converted to anthraquinones during summer. Not only the season but also the age of the plant should be taken in to great consideration since it governs not only the total amount of active constituents produced in the plants but also the proportions of the constituents of the active mixture. High proportion of pulegone in young plants of peppermint will be replaced by menthone and menthol and reduction in the percentage of alkaloids in datura as the plant ages are examples of the effect of aging in plants. Chapter-06.indd 84 10/12/2009 4:07:08 PM85CULTIVATION, COLLECTION AND PROCESSING OF HERBAL DRUGSMoreover the composition of a number of secondary plant metabolites varies throughout the day and night, and it is believed that some inter conversion would happen during day and night.Generally the leaves are collected just before the flow-ering season, e.g. vasaka, digitalis, etc., at this time it is assumed that the whole plant has come to a healthy state and contain an optimum amount of metabolites, flowers are collected before they expand fully, e.g. clove, saffron, etc., and underground organs as the aerial parts of plant cells die, e.g. liquorice, rauwolfia, etc. Since it is very difficult to collect the exact medicinally valuable parts, the official pharmacopoeia’s has fixed certain amount of foreign matter that is permissible with drug. Some fruits are collected after their full maturity while the others are collected after the fruits are ripe. Barks are usually col-lected in spring season, as they are easy to separate from the wood during this season. The barks are collected using three techniques, felling (bark is peeled off after cutting the tree at base), uprooting (the underground roots are dug out and barks are collected from branches and roots) and coppicing (plant is cut one metre above the ground level and barks are removed).Underground parts should be collected and shaken, dusted in order to remove the adhered soil; water washing could be done if the adhered particles are too sticky with plant parts. The unorganized drugs should be collected from plants as soon as they oozes out, e.g. resins, latex, gums, etc. Discoloured drugs or drugs which were affected by insects should be rejected.6.7. HARVESTING OF CRUDE DRUGSHarvesting is an important operation in cultivation tech-nology, as it reflects upon economic aspects of the crude drugs. An important point which needs attention over here is the type of drug to be harvested and the pharmacopoeial standards which it needs to achieve. Harvesting can be done efficiently in every respect by the skilled workers. Selectivity is of advantage in that the drugs other than genuine, but similar in appearance can be rejected at the site of collection. It is, however, a laborious job and may not be economical. In certain cases, it cannot be replaced by any mechanical means, e.g. digitalis, tea, vinca and senna leaves. The underground drugs like roots, rhizomes, tubers, etc. are harvested by mechanical devices, such as diggers or lifters. The tubers or roots are thoroughly washed in water to get rid of earthy-matter. Drugs which constitute all aerial parts are harvested by binders for economic reasons. Many a times, flowers, seeds and small fruits are harvested by a special device known as seed stripper. The technique of beating plant with bamboos is used in case of cloves. The cochineal insects are collected from branches of cacti by brushing. The seaweeds producing agar are harvested by long handled forks. Peppermint and spearmint are har-vested by normal method with mowers, whereas fennel, coriander and caraway plants are uprooted and dried. After drying, either they are thrashed or beaten and the fruits are separated by winnowing. Sometimes, reaping machines are also used for their harvesting.6.8. DRYING OF CRUDE DRUGSBefore marketing a crude drug, it is necessary to process it properly, so as to preserve it for a longer time and also to acquire better pharmaceutical elegance. This process-ing includes several operations or treatments, depending upon the source of the crude drug (animal or plant) and its chemical nature. Drying consists of removal of suffi-cient moisture content of crude drug, so as to improve its quality and make it resistant to the growth of microorgan-isms. Drying inhibits partially enzymatic reactions. Drying also facilitates pulverizing or grinding of a crude drug. In certain drugs, some special methods are required to be followed to attain specific standards, e.g. fermentation in case of Cinnamomum zeylanicum bark and gentian roots. The slicing and cutting into smaller pieces is done to enhance drying, as in case of glycyrrhiza, squill and calumba. The flowers are dried in shade so as to retain their colour and volatile oil content. Depending upon the type of chemical constituents, a method of drying can be used for a crude drug. Drying can be of two types - (1) natural (sun drying) and (2) artificial.Natural Drying (Sun-Drying)In case of natural drying, it may be either direct sun-drying or in the shed. If the natural colour of the drug (digitalis, clove, senna) and the volatile principles of the drug (pep-permint) are to be retained, drying in shed is preferred. If the contents of the drugs are quite stable to the temperature and sunlight, the drugs can be dried directly in sunshine (gum acacia, seeds and fruits).Artificial DryingDrying by artificial means includes drying the drugs in (a) an oven; i.e. tray-dryers; (b) vacuum dryers and (c) spray dryers.(a) Tray dryersThe drugs which do not contain volatile oils and are quite stable to heat or which need deactivation of enzymes are dried in tray dryers. In this process, hot air of the desired temperature is circulated through the dryers and this facili-tates the removal of water content of the drugs (belladonna roots, cinchona bark, tea and raspberry leaves and gums are dried by this method).Chapter-06.indd 85 10/12/2009 4:07:08 PM86 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRY(b) Vacuum dryersThe drugs which are sensitive to higher temperature are dried by this process, e.g. Tannic acid and digitalis leaves.(c) Spray dryersFew drugs which are highly sensitive to atmospheric condi-tions and also to temperature of vacuum-drying are dried by spray-drying method. The technique is followed for quick drying of economically important plant or animal constituents, rather than the crude drugs. Examples of spray drying are papaya latex, pectin, tannins, etc.6.9. GARBLING (DRESSING)The next step in preparation of crude drug for market after dryingis garbling. This process is desired when sand, dirt and foreign organic parts of the same plant, not constitut-ing drug are required to be removed. This foreign organic matter (extraneous matter) is removed by several ways and means available and practicable at the site of the preparation of the drugs. If the extraneous matter is permitted in crude drugs, the quality of drug surfers and at times, it dose not pass pharmacopoeial limits. Excessive stems in case of lobelia and stramonium need to be removed, while the stalks, in case of cloves are to be deleted. Drugs constituting rhizomes need to be separated carefully from roots and rootlets and also stem bases. Pieces of iron must be removed with the magnet in case of castor seeds before crushing and by shift-ing in case of vinca and senna leaves. Pieces of bark should be removed by peeling as in gum acacia.6.10. PACKING OF CRUDE DRUGSThe morphological and chemical nature of drug, its ultimate use and effects of climatic conditions during transporta-tion and storage should be taken into consideration while packing the drugs. Aloe is packed in goat skin. Colophony and balsam of tolu are packed in kerosene tins, while asafoetida is stored in well closed containers to prevent loss of volatile oil. Cod liver oil, being sensitive to sun-light, should be stored in such containers, which will not have effect of sunlight, whereas, the leaf drugs like senna, vinca and others are pressed and baled. The drugs which are very sensitive to moisture and also costly at the same time need special attention, e.g. digitalis, ergot and squill. Squill becomes flexible; ergot becomes susceptible to the microbial growth, while digitalis looses its potency due to decomposition of glycosides, if brought in contact with excess of moisture during storage. Hence, the chemicals which absorb excessive moisture (desiccating agents) from the drug are incorporated in the containers. Colophony needs to be packed in big masses to control autooxidation. Cinnamon bark, which is available in the form of quills, is packed one inside the other quill, so as to facilitate trans-port and to prevent volatilization of oil from the drug. The crude drugs like roots, seeds and others do not need special attention and are packed in gunny bags, while in some cases bags are coated with polythene internally. The weight of certain drugs in lots is also kept constant e.g. Indian opium.6.11. STORAGE OF CRUDE DRUGSPreservation of crude drugs needs sound knowledge of their physical and chemical properties. A good quality of the drugs can be maintained, if they are preserved prop-erly. All the drugs should be preserved in well closed and, possibly in the filled containers. They should be stored in the premises which are water-proof, fire proof and rodent-proof. A number of drugs absorb moisture during their storage and become susceptible to the microbial growth. Some drugs absorb moisture to the extent of 25% of their weight. The moisture, not only increases the bulk of the drug, but also causes impairment in the quality of crude drug. The excessive moisture facilitates enzymatic reactions resulting in decomposition of active constituents e.g. digi-talis leaves and wild cherry bark. Gentian and ergot receive mould infestation due to excessive moisture. Radiation due to direct sun-light also causes destruction of active chemical constituents, e.g. ergot, cod liver oil and digitalis. Form or shape of the drug also plays very important role in preserving the crude drugs. Colophony in the entire form (big masses) is preserved nicely, but if stored in powdered form, it gets oxidized or looses solubility in petroleum ether. Squill, when stored in powdered form becomes hygroscopic and forms rubbery mass on prolonged exposure to air. The fixed oil in the powdered ergot becomes rancid on storage. In order to maintain a good quality of ergot, it is required that the drug should be defatted with lipid solvent prior to storage. Lard, the purified internal fat of the abdomen of the hog, is to be preserved against rancidity by adding siam benzoin. Atmospheric oxygen is also destructive to several drugs and hence, they are filled completely in well closed containers, or the air in the container is replaced by an inert gas like nitrogen; e.g. shark liver oil, papain, etc.Apart from protection against adverse physical and chem-ical changes, the preservation against insect or mould attacks is also important. Different types of insects, nematodes, worms, moulds and mites infest the crude drugs during storage. Some of the more important pests found in drugs are Coleoptera (Stegobium paniceum and Calandrum grana-rium), Lepidoptera (Ephestia kuehniella and Tinea pellionella), and Archnida or mites (Tyroglyphus farinae and Glyophagus domesticus). They can be prevented by drying the drug thoroughly before storage and also by giving treatment of fumigants. The common fumigants used for storage of crude drugs are methyl bromide, carbon disulphide and hydrocyanic acid. At times, drugs are given special treat-ment, such as liming of the ginger and coating of nutmeg. Temperature is also very important factor in preservation of Chapter-06.indd 86 10/12/2009 4:07:08 PM87CULTIVATION, COLLECTION AND PROCESSING OF HERBAL DRUGSthe drugs, as it accelerates several chemical reactions leading to decomposition of the constituents. Hence, most of the drugs need to be preserved at a very low temperature. The costly phytopharmaceuticals are required to be preserved at refrigerated temperature in well closed containers. Small quantities of crude drugs could be readily stored in air-tight, moisture proof and light proof containers such as tin, cans, covered metal tins, or amber glass containers. Wooden boxes and paper bags should not be used for storage of crude drugs.6.12. QUALITY MANAGEMENTThe herbal drug manufacturers should establish a quality management department which is responsible for supervi-sion and quality control for the entire production process, and should have adequate staff, premises, instruments and equipment to meet the standard requirements of the scale of production and species identification. The quality man-agement department should monitor the environment and hygienic management, test production materials, packaging materials and the crude drugs, and issue testing reports, develop training plans and supervise their implementa-tion; and also they should manage the original records of production, packaging, testing, etc. Prior to packaging, the quality control department should test each batch of the crude drugs in accordance with the national or approved standards for crude drugs. The testing procedures should include macroscopic characters and identification, impu-rities, moisture, ash and acid insoluble ash, extracts, and assay for marker or active constituents. Pesticide residue, heavy metals and microbiological limits should comply with the national standards and the relevant requirements. The testing reports should be signed by the operator and the responsible person of the quality control department, and then filed. As far as the personnel and facilities are concerned, they should possess qualifications of college education or above in pharmacy, knowledge in alternative systems of medicines, agronomy, animal husbandry or the relevant specialties, trained on production techniques, safety, and hygiene and have experience in the production of crude drugs, quality management of crude drugs. Staff engaged in the field work should be familiar with cultiva-tion techniques, especially the use of pesticides and safety protection; those engaged in rearing should be familiar with rearing techniques.The personnel engaged in processing, packaging or testing should undergo health examinations regularly and those suffering from infectious diseases, dermatitis or open wounds shallnot be allowed to do work which is in direct contact with crude drugs. The producer should designate a person to be responsible for checking sanitation and hygiene. The applicable range and precision of instru-ments, metres, measures, weighers and balances, etc. used in production and testing, should conform to the relevant requirements, their performance status should be clearly indicated, and calibration should be conducted regularly.6.13. DOCUMENTATIONThe producer should maintain its standard operating pro-cedures for production and quality management. Detailed records for the entire production process of each crude drug should be documented, and if necessary, photos or images might be attached, which should include, origin of seeds, strains and propagation materials, production techniques and process, sowing time, quantity and area of medicinal plants, seedling, transplantation, and the type, applica-tion schedule, quantity arid usage of fertilizer, quantity, application schedule and usage of pesticide, microbicide or herbicide, Collection time and yield, fresh weight and processing, drying and drying loss, transport and storage of medicinal parts. Quality evaluations of crude drugs: description of macroscopic characters of crude drugs and records of test results. All these records, production plans and their details, contracts or agreements etc. should be filed and kept properly by a designated person.Chapter-06.indd 87 10/12/2009 4:07:08 PM7.1. INTRODUCTIONRecently there has been a shift in universal trend from synthetic to herbal medicine, which we can say ‘Return to Nature’. Medicinal plants have been known for millennia and are highly esteemed all over the world as a rich source of therapeutic agents for the prevention of diseases and ail-ments. Nature has bestowed our country with an enormous wealth of medicinal plants; therefore, India has often been referred to as the medicinal garden of the world. Countries with ancient civilizations, such as China, India, South America, Egypt, etc., are still using several plant remedies for various conditions. In this regard, India has a unique position in the world, where a number of recognized indig-enous systems of medicine, viz. Ayurveda, Siddha, Unani, Homeopathy, Yoga and Naturopathy are being utilized for the health care of people. No doubts that the herbal drugs are popular among rural and urban community of India. The one reason for the popularity and acceptability is the belief that all natural products are safe. The demand for plant-based medicines, health products, pharmaceuticals, food supplement, cosmetics, etc., are increasing in both developing and developed countries due to the growing recognition that the natural products are nontoxic, have less side effects and easily available at affordable prices. Nowadays, there is a revival of interest with herbal-based medicine due to the increasing realization of the health hazards associated with the indiscriminate use of modern medicine, and the herbal drug industries is now very fast growing sector in the international market. But unfortu-nately, India has not done well in this international trade of herbal industry due to lack of scientific input in herbal drugs. So, it would be appropriate to highlight the market potential of herbal products that would open floodgate for development of market potential in India. With these objects, we reviewed here the market potential of herbal medicine in India.The export of medicinal plants and herbs from India has been quite substantial for the last few years. India has a large endemic flora. There are more than 80,000 medicinal plants known, and nearly 180 plant-derived chemical compounds have been developed as modern pharmaceuticals, which are included in the Pharmacopoeia of India. The domestic ayurvedic market is estimated to be US$ 1 billion, and is growing at the rate of 15–20% annually. India has been the major supplier of medicinal plants in the world market until 1977, when it was kept to second position by South Korea with export worth only Rs. 16 crore during 1978–79. The quantum of export had dropped to almost half of what it was in 1976–77 when India exported medicinal plants worth around Rs. 29.8 crore. The items of export value were opium, psyltium husks and seeds, Vinca rosea, kuth roots and senna leaves and pods. At present the annual trade of Indian medicinal plants is estimated to be 37,200 tonnes valued around US$ 93,540,272.00, which is expected to be increased to US$ 629,194,624.00 by 2005. During 1980s, India was the largest supplier of medicinal plants to the world market with the supply of 10.555 metric tonnes of medicinal plant material and about 14 metric tonnes of plant-derived products and their derivatives. The annual turn over was around US$ 300 million. In 1995, psyllium husk, seeds and senna were the main export items from India. During 1998–99, India exported psyllium husk worth US$ 19.6 million and senna leaves worth US$ 22.4. India also exported finished ayurvedic and unani medicine during the year 2000–01. It exported medicine worth around US$ 128 million to various countries including United States, Germany, Russia, UK, Hong Kong and Malaysia.The global herbal industry is estimated to be US$ 50 billion annually and growing at the rate of 5.5–6.5% annually. The Indian contribution to the global industry is around 10% only. One of the important items of export, covering approximately 80% of the world requirement, is a proteolytic enzyme, papain mainly manufactured in Maha-rashtra from raw papaya fruits. The commercial production of pectin from thalmus of sunflower is also carried out at Jalgaon in Maharashtra.India is one of the few countries in the world where essential oils industry was developed at a very early stage. Indian Trade in Medicinal and Aromatic PlantsCHAPTER7Chapter-07.indd 88 10/12/2009 4:09:18 PM89INDIAN TRADE IN MEDICINAL AND AROMATIC PLANTSThe essential oils, perfumes and flavours have been asso-ciated with Indian civilization for several thousand years. Because of its vast area and a variety of soil and climate, essential oils containing plants of all types can be grown in one or the other parts of the country. India produces essential oils from wild and commercially grown plants in appreciable quantities such as palmarosa, citronella, calamus, cardamom, celery seed, cedarwood, dill, ginger, lemon grass, vetiver and rose oil. The annual production of coriander is about 243,000 tonnes, which constitute approximately 80% of the world demand. About 30% of global demand in cardamom and 15% in saffron are met by India. The annual production of saffron is approximately 150 tonnes.The most significant export is of the sandalwood oil, for which our country is the major producer, exporting approximately 50–60 tonnes to the world market. India is a leader in the production of menthol as mentha oil steadily expanded in the last decade during the year 2000–01. India exported about 3,870 tonnes of mint oil worth about Rs. 1.26 billion. India is also a leader in the production and export of high value perfumes (attars) for the world market.The domestic market of Indian traditional system of medicine comprising of ayurveda, unani, siddha and home-opathy has been reported to the tune of approximately Rs. 5,000 crore only, and India is at present exporting herbal medicines and materials to the value of about Rs. 550 crore only. In the domestic market, the ayurvedic medicines account for a major portion, about 85% as compared to unani, siddha and homeopathy system. The total patent and proprietary medicines of these systems are manufactured by over 9,500 licensed pharmacies/herbal manufacturing units spread all over India.With the development of phytochemical industry in India, domestic requirement for various medicinal plants grew considerably.Consequently, the Govt. of India has adopted restrictive export policy in respect of those crude drugs, which were indiscriminately exploited in the forest, such as rauwolfia, podophyllum, Indian rhubarb, dioscorea, kuth, jatamansi, Atropa acuminata, Artemisia brevifolia, berberis, colchicum, Ephedra gerardiana, Gentiana kurroa, Picrorhiza kurroa, Swertia chirata, Valerian wallichii, etc. However, with due permission from the Chief Conservator of Forest or officer authorized by him; the material of plantation or of nursery origin certificate can be exported.These medicines are mainly consumed within the country and some of these are also exported to the Middle East. Major destination countries are the United States, Nepal, Japan, Sri Lanka, Russia, Germany, Italy, Nigeria and UAE, and according to the survey reports, Sri Lanka, Egypt, Ban-gladesh and Mauritius are the countries having maximum export potential.The major pharmaceuticals exported from India in the recent years were isabgol, vinca extract, senna derivatives, castor oil in dehydrated form, beta ionone, papain, berberine hydrochloride and opium alkaloids.India’s export of essential oils during last few years has shown the erratic trends. The sandalwood oil share is more than 50% in the total export; the United States accounted for major share of exports of this item followed by USSR. The mentha oil has the same export trend as the cheaper quality is being exported by China. India is also exporting volatile oils to France, Japan, Sudan, Germany and Switzerland. The other important items of export value are cardamom oil, lemon grass oil, palmarosa oil, pudina oil, peppermint oil, clove oil, geranium oil, vetiver oil and lavender oil.7.2. INDIAN HERBAL TRADE IN WORLD SCENARIOThe utilization of herbal drugs is on the flow, and the market is growing step by step. The annual turnover of the Indian herbal medicinal industry is about Rs. 2,300 crore as against the pharmaceutical industry’s turnover of Rs. 14,500 crore, with a growth rate of 15%. The export of medicinal plants and herbs from India has been quite substantial in the last few years. India is the second largest producer of castor seeds in the world, producing about 125,000 tonnes per annum. The major pharmaceuticals exported from India in the recent years are isabgol, opium alkaloids, senna derivatives, vinca extract, cinchona alkaloids, ipecac root alkaloids, solasodine, Diosgenine/16DPA, menthol, gudmar herb, mehndi leaves, papian, rauwolfia, guar gum, jasmine oil, sandalwood oil, etc. The turnover of herbal medicines in India as over-the-counter products, ethical and classical formulations and home remedies of traditional systems of medicine is about US$ 1 billion and export of herbal crude extract is about US$ 80 million. The herbal drug market in India is about US$1 billion. Some of the medicinal plants, whose market potential is very high, have been identified and summarized in Table 7.1.Table 7.1 List of high-market-potential medicinal plantsAconitum ferox(Ranunculaceae)Garcinia camboga (Guttiferae)Aconitum heterophyllum(Ranunculaceae)Gymnema sylvestre(Asclepiadaceae)Allium sativum(Liliaceae)Holarrhena antidysenterica(Apocynaceae)Azadirachta indica(Meliaceae)Ocimum tenifl orum(Labiatae)Andrographis paniculata(Acanthaceae)Picrorhiza kurroa(Scrophulariaceae)Asparagus recemosus(Liliaceae)Plantago ovata(Plantaginaceae)Berberis aristata(Berberidaceae)Saraca indica(Leguminosae)Commipphora weightii(Burseraceae)Saussurea costus(Asteraceae)Crocus sativus(Iridaceae)Solanum nigrum(Solanaceae)Nardostachys jatamansi(Valerianaceae)Tinospora cordifolia(Menispermaceae)Embelica offi cinalis(Euphorbiaceae)Withania somnifera(Solanaceae)Chapter-07.indd 89 10/12/2009 4:09:19 PM90 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRY7.3. MEDICINAL PLANT-BASED INDUSTRIES IN INDIGENOUS SYSTEM OF MEDICINEIn India, it is estimated that there are about 25,000 licensed pharmacy of Indian system of medicine. Presently, about 1,000 single drugs and about 3,000 compound formula-tions are registered. Herbal industry in India uses about 8,000 medicinal plants. Table 7.2 contains some impor-tant manufacturer of herbal formulation. However, none of the pharma has standardized herbal medicines using active compounds as markers linked with confirmation of bioactivity of herbal drugs in experimental animal models. From about 8,000 drug manufactures in India, there are however not more than 25 manufactures that can be clas-sified as large-scale manufactures. The annual turnover of Indian herbal industry was estimated around US$ 300 million in ayurvedic, and unani medicine was about US$ 27.7 million. In 1998–99, it again went up to US$ 31.7 million and in 1999–2000 of the total turnover was US$ 48.9 million of ayurvedic and herbal products. Export of herbal drugs in India is around US$ 80 million. Some of the highly consumed medicinal plants are presented in the Table 7.3 with reference to their turnover. Figure 7.1(a–d) are the graphical representation of some highly consumed Indian medicinal plants vs. estimated consumption per annum (in tonnes).Table 7.2 Manufacturer of herbal formulationS. N. Name of the company1. Ansar Drug Laboratories, Surat2. Acis Laboratories, Kanpur3. Amil Pharmaceutical, New Delhi4. Allen Laboratories, Kolkata5. Bharti Rasanagar, Kolkata6. Dabur India Ltd., Ghaziabad7. Dattatraya Krishan Sandu Bros., Mumbai8. Herbals Pvt. Ltd., Patna9. Herbo-med (P) Ltd., Kolkata10. The Himalaya Drug Co., Bangalore11. Indian Herb and Research Supply Co., Saharanpur12. J & J Dechane Laboratories Pvt. Ltd., Hyderabad13. Madona Pharmaceutical Reaearch Pvt. Ltd., Kolkata14. Kruzer Herbals, New Delhi15. Shilpachem, Indore16. Hamdard (Wakf) Laboratories, Delhi17. Zandu Pharmaceutical Works Ltd., Mumbai18. Baidyanath Ayurveda Bhavan, Jhansi19. Charak Pharmaceuticals, MumbaiTable 7.3 Important plants with reference to tradeS. N.Plant name Common namePlant partEstimat-ed con-sump-tion (tonnes)1. Aconitum heterophyllum Atis Root 202. Acorus calamus Vacha Rhizome 1503. Aloe vera Aloes Leaf 2004. Anacyclus pyrethrum Akkarkara Fruit 505. Andrographis paniculata Kalmegh Aerial part2506. Asparagus recemosus Satavatri Root 5007. Berberis aristata Daru haldi Root 5008. Cedrus deodara Deodar Heart Wood2009. Chlorophytum borivilianumSafed musli Root 2510. Cinnamomum zeylanicum Dalchini Bark 200–30011. Commipphora wrightii Guggul Gum resin50012. Crocus sativus Kesar Stigma 513. Cyprus rotundus Nagar motha Rhizome 15014. Eclipta alba Bhringraj Aerial part50015. Elettaria cardamomum Elaichi Seed 6016. Embelia ribes burm Vidanga Fruit 20017. Glycyrrhiza glabra Milathi Root 5,00018. Hedychium spicatum Kapurkachri Rhizome 40019. Hemidesmus indicus Anantmool Root 20020. Holarrhena pubescens Kurchi Bark 15021. Justicia adhatoda Vasaka Leaf 50022. Mucuna pruriens Kaunch beej Seed 20023. Myristica fragrans Jaiphal Fruit 50024. Nardostachy gradifl ora Jatamansi Root 20025. Embelica offi cinalis Amla Fruit 10,00026. Picrorhiza kurroa Kutki Root 20027. Piper cubeba Cubeb Fruit 15028. Piper longum Pipramul Fruit 20029. Piper nigrum Black pepper Fruit 15030. Plumbago zeylanica Chitrak Root 50031. Pueraria tuberose Vidarikanda Root 20032. Saraca indica Ashoka Bark 1,20033. Senna alexandrian Senna Leaf and pod1,00034. Strychnos nux vomica Luchia Seed 1,00035. Swertia chirata Chirayita Whole plant30036. Syzygium aromaticum syn Eugenia aromaticumLaung Flower bud15037. Syzygium cumini Jaman beej Seed 30038. Trachyspermum ammi Ajwain Fruit 20039. Terminalia bellrica Bahera Fruit 50040. Terminalia chebula Harar Fruit 50041. Tinospora cardifolia Guduchi Stem 1,00042. Valeriana jatamansi Tagar Root and Rhizome150Chapter-07.indd90 10/12/2009 4:09:19 PM91INDIAN TRADE IN MEDICINAL AND AROMATIC PLANTSAconitumheterophyllumAcoruscalamusAloeveraAnacycluspyrethrumAndrographispaniculataAsparagusrecemosusBerberisaristataCedrusdeodaraChlorophytumborivilianum500450400350300250200150100500CommipphorawrightiiCinnamomumzylanicumFig. 7.1(a) Important Indian medicinal plants vs. estimated con-sumption per annum (in tonnes)CrocussativusCyprusrotundusEcliptaalbaElettariacardamomumEmbeliaribesburmGlycyrrhizaglabraHedychiumspicatumHemidesmusindicusHolarrhenapubescensJusticiaadhatodaMucunapruriens0500100015002000250030003500400045005000Fig. 7.1(b) Important Indian medicinal plants vs. estimated con-sumption per annum (in tonnes)010002000300040005000600070008000900010000MyristicafragransNardostachygradifloraEmbelicaofficinalisPicrorhizakurroaPipercubebaPiperlongumPipernigrumPlumbagozeylanicaPuerariatuberoseSaracaindicaSennaAlexandrianFig. 7.1(c) Important Indian medicinal plants vs. estimated con-sumption per annum (in tonnes)01002003004005006007008009001000StrychnosnuxvomicaSwertiachirataSyzygiumaromaticumSyzygiumcuminiTrachyspermumammiTerminaliabellricaTerminaliachebulaTinosporacardifoliaValerianajatamansiFig. 7.1(d) Important Indian medicinal plants vs. estimated con-sumption per annum (in tonnes)7.4. EXPORT POTENTIAL OF INDIAN PHYTO-PHARMACEUTICAL PRODUCTSIndian phyto-pharmaceutical products, which are in demand in the international market for their quality and potency, are:A � rtemisinin: This is sesquiterpene lactone obtained from herb Artemisia annua, family Asteraceae, effective in treating malaria including cerebral malaria.Berberine hydrochloride and berberine sulphate: �This is benzyl isoquinoline alkaloidal salt obtained from Berberis spp. viz. B. aristata, B. vulgaris. It is used as tonic astringent, febrifuge, hepatic dysfunction, diabetes and in gastroenteritis.Colchicine: � This is a yellowish benzyl tetra-hydroiso-quinoline type alkaloid, obtained from many species of Colchicum (e.g. C. luteum., C. speciosum) and also from genera Androcymbium, Gloriosa, Iphigenia, Lit-tonia and sandersonia. It is used to relieve gout and rheumatic problems.Diosgenin, Hecogenin and Solasodine: � These are natural steroidal sapogenins, obtained from Dioscorea species (e.g. D. deltoidea, D. maxicana, D. compositae and D. floribunda); Agave spp. and Solanum spp. respectively used in various hormonal preparations including birth control pills.Ephedrine: � It is a protoalkaloid obtained from various spp. of Ephedra (Ma-huang) and may also be prepared by synthesis. It is used for the relief of asthma and hay fever.Chapter-07.indd 91 10/12/2009 4:09:19 PM92 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYHyoscine and Hyoscyamine: � These are tropane alkaloids obtained from D. stramonium, Hyoscyamus niger and H. muticus. It is used as sedative in preoperative medication before the induction of anaesthesia and in ophthalmic practice to dilate the pupil of the eye.Morphine, Codeine and Papaverine: � These are the opium alkaloids obtained from the latex of Papaver somniferum. It is used as a pain killer (morphine) and antitussive (codeine).Psoralen: � This is furanocumarin obtained from Psoralea corylifolia. It is used in leucoderma and skin problems.Quinine and Quinidine: � These are quinoline alkaloids obtained from various spp. of Cinchona bark used as antimalarials.Reserpine, Ajmalicine: � These are the indole alkaloids obtained from Rauwolfia serpentine,used to treat hyperten-sion and as a vasodilator.Rutin: � This is yellow coloured crystalline flavonol glyco-side obtained from buckwheat, i.e. Fagopyrum esculentum (Polygonaceae). It is included in dietary supplements and claimed to be benefit in treating conditions characterized by capillary bleeding.Sennosides A and B: � This is anthraquinone glycoside obtained from Cassia senna and is used to treat habitual constipation.Taxol (Paclitaxel): � This is diterpene ester obtained from Taxus species (e.g. T. brevifolia and T. wallichiana; Taxaceae), used as anticancer agent.Xanthotoxin: � This is furanocoumarin obtained from Ammi majus and Heracleum candicans, used in leucoderma and other skin problems.7.5. INDIAN MEDICINAL PLANTS USED IN COSMETIC AND AROMATHERAPYFollowing is the list of few Indian medicinal plants, which are in demand in the domestic as well as international market being useful in herbal cosmetic and in aromatherapy.Aloe vera (Kumari) Rosa damascena (Rose),Pelargonium graveolens (Geranium)Matricaria chamomillaOcimum basilicum and O. sanctumLawsonia innermis (Mehandi)Hibiscus rosa-sinensis (Japa) Mentha piperita (Peppermint oil)Mentha arvensis (Mint oil) Eucalyptus globulus (Eucalyptus oil)7.6. INDIAN MEDICINAL PLANTS IN CRUDE FORMThe following list of Indian medicinal plants having export potential in the crude form as well as their phyto-pharma-ceutical products:Aconitum spp. (Vastsanabh) Acorus calamus (Vacha)Adhatoda vasica (Vasa) Herberts aristata (Daruhaldi)Cassia senna (Senna) Colchicum luteum (Colchicum)Hedychium spicatum (Kapur Kachri)Heracleum candicans (Kaindal)Inula racemosa (Pushkarmool) Juglans regia (Akhrot)Juniperus spp. (Aarar) Plantago ovata (Isabgol)Picrorhiza kurroa (Kutki) Podophyllum hexandrum (Bankakri)Punica granatum (Anar) Rauwolfi a serpentina (Sarpagandha)Rheum australe (Revandchini) Swertia chirata (Chirata)Valeriana wallichii (Tagar) Zingiber offi cinale (Adrak)7.7. SPICESSpices form an important ingredient of culinary prepara-tions in the tropics. They are added to the food in minor quantities to alter the taste and flavour of the preparation. Though they do not contribute to the energy content of the diet, they help to increase the digestion of the diet by enhancing the secretion of the digestive enzyme in the alimentary tract and by increasing the perspiration. There are four major groups of active constituents present in the spices, responsible for all these properties: (i) Volatile oils (ii) Phenolics (iii) Alkaloids and (iv) Sulphur-containing compounds.Volatile OilsVolatile oils are sweet-smelling liquids, and they emit fragrance to the food and are also slight bitter in taste. Thus, they help to enhance the secretion of digestive enzyme in the alimentary tract. All spices belonging to the apiaceae (umbelliferous fruits and their leaves) and the lamiaceae (leafy spices) are rich in volatile oils. Since the oils are lost on cooking, these spices are mostly added as condiments.PhenolicsPhenolics component contribute to the taste, colour and flavour of a number of spices. The phenols present in spices are simple in structure mostly containing single aromatic ring, e.g. gingerols (ginger), phenolic amines are the pungent principles (capsaicins) in red pepper and phenylpropenes are present in cloves (eugenol) and fennel (anethole).AlkaloidsAlkaloids are the largest group of nitrogenous natural organic compounds but only a few spices belonging to the Chapter-07.indd 92 10/12/2009 4:09:19 PM93INDIAN TRADE IN MEDICINAL AND AROMATIC PLANTSgenus piper contain them. Alkaloids present in this genus are of piperidine type.Sulphur CompoundsSpices such as mustard, onion and garlic owe their pungency andcharacteristic odour to sulphur-containing compounds. These compounds are present in the form of glucosinolate (mustard seed) and are volatile with an offensive odour (onion, garlic and asparagus).7.8. EXPORT OF SPICES INDIAFollowing is the list of spices being exported from India to East Asia, the United States, West Asia, European Com-munity and Africa, UAE, Singapore, Germany, France, Canada, Sri Lanka, Japan, Malaysia, Russia, Bangladesh, Pakistan, Saudi Arabia and Netherlands.Although other countries like China, Brazil, Thailand, etc., have also started export of spice, but even then the demand for Indian spices is not being affected.Spices exports have registered substantial growth during the last decade, registering an annual average growth rate of 11.1% in value terms. During the year 2007–08, the export earnings from spices have surpassed US$ 1 billion mark for the first time and registered an all time high both in terms of quantity and value in spice exports. In 2007–08, the export of spices from India has been 444,250 tonnes valued US$ 1,101.80 million registering an increase of 39% in value over 2006–07. India commands a formidable posi-tion in the World Spice Trade with 48% share in volume and 44% in value (Table 7.4 and Figure 7.2).The history of Indian spice is very old, as there are evi-dences of India having trade of vegetable drugs and spices with Greece even before Alexander’s invasion in 327 B.C. India’s glory for the land of spice and perfumery attracted foreigners (French, British, Arab, Portuguese and Dutch). Portuguese invaded India and controlled over the spice trade of the country. They were taken over by Dutch, who exploited spices of India for many years. Later the British Empire took over and shared most of the world spice trade with Holland. Arabs had taken the spice products from Table 7.4 Item wise export of spices from IndiaItem2005–06 2006–07 2007–08Qty Value Qty Value Qty Value(MT) (Rs. lakh) (MLS US $) (MT) (Rs. lakh) (MLS US $) (MT) (Rs. lakh) (MLS US $)Pepper 17,363 1,5095 34.06 28,750 30,620 67.90 35,000 51,950 129.05Cardamom (S) 863 2,682 6.05 650 2,236 4.96 500 2,475 6.15Cardamom (L) 1,046 1,155 2.61 1,500 1,695 3.76 1,325 1,500 3.73Chilli 113,174 40,301 90.93 148,500 80,775 179.13 209,000 109,750 272.62Ginger 9,411 4,296 9.69 7,500 3,975 8.81 6,700 2,800 6.96Turmeric 46,405 15,286 34.49 51,500 16,480 36.55 49,250 15,700 39.00Coriander 23,756 6,771 15.28 20,500 7,462 16.55 26,000 11,025 27.39Cumin 12,879 9,819 22.16 26,000 20,150 44.68 28,000 29,150 72.41Celery 4,165 1,501 3.39 3,550 1,321 2.93 2,900 1,325 3.29Fennel 5,725 2,782 6.28 3,575 2,380 5.28 5,250 2,850 7.08Fenugreek 15,525 3,403 7.68 8,500 2,699 5.98 11,100 3,300 8.20Other seeds (1) 12,670 3,322 7.50 8,000 2,240 4.97 8,850 3,125 7.76Garlic 34,688 4,798 10.83 11,500 2,128 4.72 675 400 0.99Tamarind 14,101 3,078 6.95 10,200 3,000 6.65 11,250 3,100 7.70Nutmeg and Mace 1,530 3,117 7.03 2,100 4,274 9.48 1,300 2,875 7.14Vanilla 72 1,227 2.77 125 1,996 4.43 200 1,775 4.41Other Spices (2) 7,033 4,415 9.96 9,300 4,280 9.49 7,750 5,000 12.42Curry powder 9,340 7,838 17.69 9,500 8,693 19.28 11,500 11,100 27.57Mint products (3) 14,544 81,321 183.49 16,250 110,095 244.15 21,100 128,050 318.08Oils and Oleoresins 6,074 50,557 114.08 6,250 51,079 113.27 6,600 56,300 139.85TOTAL 350,363 262,762 592.89 373,750 357,575 792.95 444,250 443,550 1,101.80(1) Includes bishops weed (Ajwain seed), dill seed, poppy seed, aniseed, mustard, etc.(2) Includes asafoetida, cinnamon, cassia, cambodge, saffron, spices (NES), etc.(3) Includes menthol, menthol crystals and mint oils.* Source: DGCI&S., Calcutta/Shipping Bills/Exporters’ Returns.Chapter-07.indd 93 10/12/2009 4:09:19 PM94 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYof last year. However, exports of pepper and chilli have declined both in terms of quantity and value as compared to last year. During the period, export of ginger and mint products has declined in quantity only.During April–December 2008, the export of pepper from India has been 19,100 tonnes valued at Rs. 317.77 crore as against 27,580 tonnes valued Rs. 400.20 crore of last year. The average export price of pepper has gone up from Rs. 145.11 per kg in 2007 to Rs. 166.37 per kg in 2008. The low inventory in the major international markets due to the economic recession is reported to be the major reason for the decline in exports.During the period, India has exported 141,000 tonnes of chilli and chilli products valued Rs. 793.18 crore as against 149,755 tonnes valued Rs. 807.03 crore of last year. The traditional buyers of Indian chilli, viz. Malaysia, Indonesia and Sri Lanka continued their buying this year also. It is expected that the export will pick up in the coming months as the new crop comes to market.The export of seed spices has shown an increasing trend both in the quantity and value as compared to last year. The export of coriander seed during April–December 2008 has been 19,600 tonnes valued at Rs. 137.23 crore as against 19,150 tonnes valued at Rs. 77.69 crore of last year, registering an increase of 77% in value. The unit value of export has gone up from Rs. 40.57/kg in 2007 to Rs. 70.01/kg in 2008.The export of cumin seed during April–December 2008 has increased considerably and the export has been 28,500 tonnes valued at Rs. 296.13 crore as against 18,885 tonnes valued at Rs. 199.09 crore. The export of cumin up to December 2008 is an all-time record both in terms of quan-tity and value. The export of cumin has shown an increase of 51% in quantity and 49% in value terms as compared to last year. The reported crop failure in other major producing countries, viz. Syria, Turkey and Iran has helped India to achieve this substantial increase in the export of cumin.The export of value-added products like curry powder and spice oils and oleoresins have also shown substantial increase both in terms of quantity and value as compared to last year. During April–December 2008, a total quantity of 10,500 tonnes of curry powder and masalas valued Rs. 124.45 crore has been exported as against 8,375 tonnes valued at Rs. 81.10 crore of last year. During April–December 2008, the export of spice oils and oleoresins has been 5,550 tonnes valued at Rs. 574.23 crore as against 4,815 tonnes valued at Rs. 404.04 crore of last years, registering an increase of 42% in value and 15% in volume.Against the export target of 425,000 tonnes valued Rs. 4,350.00 crore (US$ 1,025.00) for the year, the achievement of 334,150 tonnes valued Rs. 3,810.95 crore (US$ 860.40 million) up to December 2008 is 79% in quantity, 88% in rupee value and 84% in dollar terms of value. The export of spices like cumin, fenugreek, nutmeg and mace, vanilla and other seeds have already achieved the respective targets fixed for the year 2008–09.southern India and established it even after independence Spices have continued to be the main attraction of inter-national trade in India. The Government of India had established separate board as ‘Spice Board of India’, for promoting the spice trade which control their production and quality. Besides, the Spice Board, the Indian Institute of Spices Research (HSR) was established at Calicut in 1986, which is responsible for providing latest biotechnology for more production of spices.VolumeValueIndia44% Other56%India48%Other52%Fig. 7.2 India’s share in world trade of spices (2007–08)Southern states of India remained the main centre of region of spice production. Even today, Southern states of the country produce most of the spices.At present Kerala tops in the production of black pepper, cardamom and ginger, while producing substantial quan-tities of long pepper and turmeric; Andhra Pradesh has monopoly in the production of turmeric and chillies. More than half of the country’s chillies and turmeric productionis produced by the State of Andhra Pradesh alone. Cur-rently about 50 million tonnes of chillies were produced by the Andhra Pradesh.The spices export during April–December 2008 is esti-mated as 334,150 tonnes valued Rs. 3,810.95 crore (US$ 860.40 million) as against 325,320 tonnes valued Rs. 3,320.00 crore (US$ 821.45 million) in the corresponding period of the last financial year. Compared to last year, the export has shown an increase of 15% in rupee value and a 3% in quantity. In dollar terms, the increase is 5%, according to data released by Spices Board.Spice oils and oleoresins including mint products con-tributed 42% of the total export earnings. Chilli contrib-uted 21% followed by pepper 8%, cumin 8% and turmeric 5%.During April–December 2008, export of most of the major spices have shown an increasing trend both in terms of quantity and value as compared to the same period Chapter-07.indd 94 10/12/2009 4:09:19 PM8.1. INTRODUCTIONAromatic plants are plants that possess aromatic compounds, most of which are essential oils which are volatile in room temperature. These compounds are synthesized and stored in a special structure called gland, which is located in dif-ferent parts of plant such as leaves, flowers, fruits, seeds, barks and roots. These essential oils can be extracted by various physical and chemical processes, such as steam distillation, maceration, expression, enfleurage and solvent extraction. They are mainly used as flavours and fragrances. However, from ancient times, these plants have been used as raw materials for cosmetics, pharmaceuticals, botanical pesticides, etc.Importance of Aromatic PlantsAromatic Plants can be divided into four groups based on how they are utilized, viz.: A � s raw materials for essential oils extraction: This is the major use of aromatic plants and is the one dealt with in this paromatic plantser.As spices: � These are plants in which their nonleafy parts are used as a flavouring or seasoning.As herbs: � These are plants in which their leafy or soft flowering parts are used as a flavouring or seasoning.Miscellaneous group: � These are aromatic plants used in some ways other than the ones mentioned above, e.g. as medicines, cosmetics, dyes, air fresheners, disinfectants, botanical pesticides, herbal drinks/teas, pot pourri, insect repellents, etc.People have made extensive use of aromatic plants from time immemorial. The Egyptian, the Persian and the Babylonian were known to grow and use aromatic plants in making perfumes and other scented waters from a distillation of rose petals and orange blossoms. Oriental people were also fond of aromatic plants. These aromatic plants were grown in the palace compounds and used as raw materials to make perfumes, scented water and a dozen of other aromatic products.8.2. IMPACT OF INDUSTRIALIZATIONThe techniques of essential oils extraction from aromatic plants have been known for thousands of year. These essen-tial oils have been used in home-made perfumes, scented water, traditional medicine, etc. These plants were normally grown in the backyard and collected for use whenever there was a need. With the advance of industrialization through large-scale production and modern facilities for process-ing and utilization, aromatic plants and their products have become very popular. However, as production costs become more and more expensive, it is necessary to come up with practical solution, i.e. the invention of synthetic compounds that are almost the same as natural materials. This has considerably reduced the use of natural flavour and fragrant materials.Volatile Oil A substance of oily consistency and feel, derived from a plant and containing the principle to which the odour and taste of the plant are due (essential oils), in contrast to a fatty oil, a volatile oil evaporates when exposed to the air and thus is capable of distillation It may also be obtained by expression or extraction as many volatile oils identical to or closely resembling the natural oils can be made syn-thetically. This is also known as ethereal oil.The essential oils industry was traditionally a cottage industry in India. Since 1974, a number of industrial com-panies have been established for large-scale production of essential oils, oleo resins and perfume. The essential oils from plants being produced in India include ajwain oil, cedar wood oil, celery oil, citronella oil, davana oil, eucalyp-tus oil, geranium oil, lavender oil, lemon grass oil, mentha oil, palmarosa oil, patchaouli rose oil, sandal wood oil, tur-pentine oil and vetiver oil. The manufacture of turpentine Utilization of Aromatic Plants and Derived ProductsCHAPTER8Chapter-08.indd 95 10/12/2009 4:10:59 PM96 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYoil and resin from pine is a sizable and well-established industry in India having 10,000–25,000 tones annual pro-duction of the oil—α-pinine and δ-3-carene being two vital components produced from the oil. α-Ionone from lemongrass oil for perfumery and β-ionone for vitamin A synthesis are produced in India . Before 1960, menthol was not produced in India but the introduction of Japanese mint, Mentha arvensis and subsequent improvements therefore enabled India to produces over 500 tones of menthol, and now tops the world market in export of natural menthol. Although the production of major oils is highly organized as a number of developing countries have volatile oil rich flora not fully utilized or cultivated. Essential OilsThe chemical components of essential oils can be divided into two main categories: the hydrocarbon monoterpenes, diterpenes and sesquiterpenes, as well as some oxides, phenolics and sulphur- and nitrogen-containing material. Common terpenes include limonene, which occurs in most citrus oils and the antiseptic pine, found in pine and terpene oils. Important sesquterpenes include chamzulene and farnesene, which occur in chamomile oil and which have been widely studied for antiinflammatory and bacte-ricidal properties. The extensive occurrence of ester in essential oils includes linalyl acetate, which is a component of bergamot and lav-ender, and geranyl acetate that is found in sweet marjoram. Other common esters are the bornyl, eugenyl and laven-dulyl acetate. The characteristic fruity aromas of esters are claimed to have sedative and fungicidal properties. Aldehydes are also clamed to have sedative properties, the most common being citralnellal and neral found in lemon scanted oils; citral also has antiseptic properties. Equally pungent to the aldehydes in many instances are the ketones, such as jasmone and funchone found in jasmine and fennel oil, respectively. Ketones, such as camphor, carnone, methone and pine comphone, found in many proprietary preparations are effective in upper respiratory tract complaints. However, some ketones are also among the more toxic components of essential oils, and are found in pennyroyal and buchu.The alcohol within essential oils is generally nontoxic. Commonly occurring terpene alcohols include citronel-lal found in rose, lemon and eucalyptus, also geramnial, bornenol, fornenesol, menthol, nerol and linalool occur-ring in rose wood and lavender. Alcohol has antiseptic and antiviral properties, and in aromatherapy, they are claimed to have an uplifting quality A wide range of oxides occur in essential oils including ascaridol, bisabolol and bisaleolone oxides and linalool oxide from hyssop. The most important oxide, however, is cineole. Also known as eucalyptus oil, it occurs extensively in other oils such as bey laurel, rosemary and cajuput. It is used medicinally for its expectorant properties. Utilization of essential oils in different industries has been summarized in Figure 8.1.Insecticide industry Cosmetics and toiletriesMotor industryPaint industryPetroleum industryTextile industry Paper and printing industry AdhesivesTobacco industryMedicalDental preparationEssential oil Food beveragesFig. 8.1 Utilization of essential oilsIndian scenarioIndia is one of the few countries in the world having varied agro climatic zones suitable for the cultivation of a host of essential oils bearing plants. Due to increased awareness of health hazards associated with synthetic chemicals coupled with the increase coast of petroleum products, the use of essential oils has been gradually increasing. The consumers are showing increasing preference for natural material over the synthetic. During the last few years with the spurt in the production of essential oils, it is emerging as a poten-tial agro-based industry in India. At present in India about 30% of the fine chemical used annually in perfumes and flavours come from essential oils. The total consumption of perfumery and flavourings material in India is abut 3,800 MT/annum valued at Rs. 100 crore. Food, dental, pharmaceutical flavours share is around 700 MT, and the rest represents perfumery. The estimated production of perfumery raw material is around 500 tones/annum valued at Rs. 400 crore. According to Trade Development Author-ity of India, the total production of fragrance excluding formulation for captive consumption by the user industry is about Rs. 120 crore/annum. A number of essential oils form palmarosa, citronella, ginger grass, basil, mint, lemon grass, eucalyptus, cedar wood, lavender oil, davana oil, celery seed oil, fennel and other oils have been widely used in a variety of products in India. Out of these the essential oils currently being produced in India are oil of citronella, lemongrass, basil, mint, sandalwood, palmarosa, eucalyp-tus, cedar wood, vetiver and geranium. Rose oil, lavender, davana oil, oil of khus and ginger grass are produced in small quantities. During last forty year, the importance of developing essential oils bearing plants is being increas-ingly realized. With the introduction of Japanese mint and subsequent improvement there upon, India produces 5,000 tones of menthol valued at Rs. 100 crore and is one Chapter-08.indd 96 10/12/2009 4:10:59 PM97UTILIZATION OF AROMATIC PLANTS AND DERIVED PRODUCTSof the leading menthol-producing country. Presently, the areas under mint cultivation are estimated to be around 40,000 hectares, mainly in U.P., Punjab, Haryana and to some extent in Bihar and M.P. The export of essential oils during the year 1991–92 has been Rs. 53.6 crore as against Rs. 40 crore during the year 1990–91, thereby registering an increases of 37% over the last year. An amount of Rs. 61 crore has been saved in foreign exchange annually by means of production of certain oils of mint, aromatic grass, linalool, geranium, lavender and rose oil during 1991–92. With the increase in production of above essential oils, it would be possible for the country to save more valuable foreign exchange in the coming years.The magic items of export are ginger oil, sandal wood oil, lemon grass oil, jasmine oil and other essential oils. During the year 1991–92, export of sandalwood oil has registered a recorded figure of Rs. 13 crore compared to Rs. 6.2 crore during 1990–91. The major buyers of Indian essential oils being Russia, United States, France, UK, Netherlands, UAE, Saudi Arabia, Spain, Morocco, Germany, Australia, Pakistan, Korea, and Taiwan, etc. Similarly, citronella oil pro-duction has reached 500 tons when it was totally imported 55 years ago. Also jasmine and tuberose concentrate from south India have created a marks in world marked. Thus, an interesting scenario in the development of natural essential oils in India has enraged. World scenarioIndia ranks 26th in import and 14th in respect of export in world in the trade of essential oils. United States, France and Germany are the top three countries in the world in the trade of essential oils. India holds around 7% of import and 1.1% of export. The values of export from India during 1991–92 to three major countries like United States, France and Germany have been to the tune of Rs. 21.2 crore with major share going to United States (Rs. 8.2 crore) and France (Rs. 7.39 crore).The world trade in essential oils and its product is vast, and the oils of major importance are aniseed, citronella, clove, geranium, lemon grass, peppermint oil, patchouli, sandal-wood, vetiver, mint oil, lemongrass and palmorosa, etc. Future demandApproximately 90% of the present requirement of essential oils in the country is met by the indigenous production and 10% from import. In 1950, the production was hardly 7,580 tones, which has since been rising to 8,000 tones. This has been both vertical and horizontal growth in the production of essential oils. Peppermint, spearmint and other mint oil constitute 68% of total volume of production of essential oils in the country. Other important varieties which constitute 28% of the total production are basil oil, citronella oil, eucalypts oil, lemongrass, palmorosa, and sandalwood and vitever oil. The annual growth rate of pharmaceutical industry in terms of volume and value is expected to be between 11% and 13% in the next five years. The other important sector showing rapid expan-sion is the processed food industry particularly ice cream and confectionery items. Fragrance finds use in toiletries and personal care products. Volume wise toiletries consti-tute 90% of all these products. The annual production of toiletries has been estimated by Toilet Makers Association from 3.5 lakh tones in 1991 to 4.8 lakh tones in 1995, at an annual growth rate of 8%. The requirement of essential oils by consumer industries under fragrances, flavour and aroma chemicals are 60%, 20% and 20%, respectively.The association of essential oils manufactures estimated growth in export value from Rs. 50 corer in 1991–92 to Rs. 125 corer in 1995–96. India ranks 14th in the world export trade, and its share being at an average 0.6–0.8% of the total. These are an ample room for penetration into the foreign market especially to the newly developing countries of the middle and for east. Export of major essential oils from IndiaMentha arvensis and mint oil, cedar wood oil, clove oil, euca-lyptus oil, tuberose concentrate, palmarosa oil, patchouli oil, sandalwood oil, lemongrass oil, davana oil, coriander oil, dill oil, spearmint oil, rose oil, Mentha piperita, jasmine concentrate, Jasmine oil. 8.3. TOXOCITY OF ESSENTIAL OILSWith the latest therapeutic trend towards aromatherapy and excessive use of essential oils under the labels of natural products, the knowledge of toxicity of essential oils has become important to avoid their abusive use.As a general rule, the acute toxicity of essential oils by the oral route is low or very low; e.g. many of the oils used have an LD50 between 2 and 5g/kg body weight (e.g. anise, eucalyptus and clove) and for most of them greater than 5 g/kg body weight (e.g. chamomile, citronella, lavender, marjoram and vetiver). Other oils have further low LD50 between 1 and 2 g/kg for sweet basil, taragon, hyssop (1.5 g/kg), savoury (1.37 g/kg), sassafras (1.9 g/kg), winter green (0.9–3.25 g/kg), chenopodium (0.25 g/kg), thuja (0.83 g/kg), pennyroyl (0.4 g/kg) and mustard oil (0.34 g/kg).A review of the available literature shows that serious accident involves the young children, due to the inges-tion of oils such as clove (eugenol) eucalyptus, pennyroyl (pulegone), winter green (methyl salicylate deadly) and parsley (apiole) in large quantity.The chronic toxicity of essential oils is also not well known at least for uses, such as aromatherapy as well as for any other route of administration as the doses in which they are used are too low for chronic toxicity.At present in India about 30% of the fine chemicals used annually in perfumes and flavour areMedicinal plants became one of its major objects of interest and in time, phytochemists succeeded in isolating the pure active constituents. These active constituents replaced the crude drugs, with the development of semisynthetic and synthetic medicine, they became predominant and gradually pushed the herbal drugs, which had formerly been used, into the background. It was a belief that the medicinal plants are of no importance and can be replaced by man-made synthetic drugs, which in today’s scenario is no longer tenable. The drug plants, which were rapidly falling into disuse a century ago, are regaining their rightful place in medicine. Today applied science of pharmacognosy has a far better knowledge of the active constituents and their prominent therapeutic activ-ity on the human beings. Researchers are exploiting not only the classical plants but also related species all over the world that may contain similar types of constituents. Just like terrestrial germplasm, investigators had also diverted their attention to marine flora and fauna, and wonderful Chapter-01.indd 7 10/12/2009 3:47:10 PM8 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYmarine natural products and their activities have been studied. Genetic engineering and tissue culture biotech-nology have already been successful for the production of genetically engineered molecules and biotransformed natural products, respectively.Lastly, crude drugs and their products are of economi-cal importance and profitable commercial products. When these were collected from wild sources, the amount col-lected could only be small, and the price commanded was exorbitantly high. All this has now changed. Many of the industrially important species which produced equally large economic profits are cultivated for large-scale crop produc-tion. Drug plants, standardized extracts and the therapeu-tically active pure constituents have become a significant market commodity in the international trade. In the light of these glorious facts, scope of pharmacognosy seems to be enormous in the field of medicine, bulk drugs, food supplements, pharmaceutical necessities, pesticides, dyes, tissue culture biotechnology, engineering and so on.Scope for doctoral graduates in pharmacognosy is going to increase in the coming years. The pharmacognosist would serve in various aspects as follows:Academics: Teaching in colleges, universities, museums and botanical gardens.Private industry: Pharmaceutical companies, consumer products testing laboratories and private commercial testing laboratories, the herbal product industries, the cosmetic and perfume industries, etc.Government: Placement in federal agencies, such as the Drug Enforcement Agency, the Food and Drug Admin-istration, the U.S. Department of Agriculture, Medicinal plant research laboratories, state agencies like forensic laboratories, environmental laboratories, etc.Undoubtedly, the plant kingdom still holds large number of species with medicinal value which have yet to be discov-ered. Lots of plants were screened for their pharmacological values like, hypoglycaemic, hepatoprotective, hypotensive, antiinflammatory, antifertility, etc. pharmacognosists with a multidisciplinary background are able to make valuable contributions in the field of phytomedicines.1.5. FUTURE OF PHARMACOGNOSYMedicinal plants are of great value in the field of treatment and cure of disease. Over the years, scientific research has expanded our knowledge of the chemical effects and composition of the active constituents, which determine the medicinal properties of the plants. It has now been universally accepted fact that the plant drugs and remedies are far safer than that of synthetic medicines for curing the complex diseases like cancer and AIDS. Enormous number of alkaloids, glycosides and antibiotics have been isolated, identified and used as curative agents. The modern devel-opments in the instrumental techniques of analysis and chromatographical methodologies have added numerous complex and rare natural products to the armoury of phy-tomedicine. To mention a few, artemissinin as antimalarial, taxol as anticancer, forskolin as antihypertensive, rutin as vitamin P and capillary permeability factor and piperine as bioavailability enhancer are the recent developments. Natural products have also been used as drug substitutes for the semisynthesis of many potent drugs. Ergotamine for dihydroergotamine in the treatment of migraine, podophyl-lotoxin for etoposide, a potent antineoplastic drug or sola-sodine and diosgenin that serve for the synthetic steroidal hormones are the first-line examples of the recent days. In the Western world, as the people are becoming aware of the potency and side effects of synthetic drugs, there is an increasing interest in the plant-based remedies with a basic approach towards the nature. The future developments of pharmacognosy as well as herbal drug industry would be largely dependent upon the reliable methodologies for identification of marker compounds of the extracts and also upon the standardization and quality control of these extracts. Mother earth has given vast resources of medicinal flora and fauna both terrestrial and marine, and it largely depends upon the forthcoming generations of pharma-cognosists and phytochemists to explore the wonder drug molecules from this unexploited wealth.Little more needs to be said about the present-day impor-tance of medicinal plants, for it will be apparent from the foregoing that the plant themselves either in the form of crude drugs or even more important, for the medicinally active materials isolated from them, have been, are and always will be an important aid to the physician in the treatment of disease.1.6. PHARMACOGNOSTICAL SCHEMETo describe drugs in a systematic manner is known as pharmacognostical scheme, which includes the following headings:Biological SourceThis includes the biological names of plants or animals yielding the drug and family to which it belongs. Botanical name includes genus and species. Often some abbrevia-tions are written after the botanical names, of the biologist responsible for the classification, for example, Acacia arabica Willd. Here Willd indicates the botanist responsible for the classification or nomenclature. According to the biennial theory, the botanical name of any plant or animal is always written in italic form, and the first letter of a genus always appears in a capital later.Biological source also includes the family and the part of the drug used. For example, biological source of senna is, Senna consists of dried leaflets of Cassia angustifolia Delite, belonging to family Leguminosae.Chapter-01.indd 8 10/12/2009 3:47:10 PM9HISTORY, DEFINITION AND SCOPE OF PHARMACOGNOSYGeographical SourceIt includes the areas of cultivation, collection and route of transport of a drug.Cultivation, Collection and PreparationThese are important to mention as these are responsible for quality of a drug.Morphological CharactersIn case of organized drugs, the length, breadth, thickness, surface, colour, odour, taste, shape, etc. are covered under the heading morphological characters, whereas organolep-tic properties (colour, odour, taste and surface) should be mentioned, if the drug is unorganized.Microscopical CharactersThis is one of the important aspects of pharmacognosy as it helps in establishing the correct identity of a drug. Under this heading all the detailed microscopical characters of a drug is described.Chemical ConstituentsThe most important aspect which determines the intrinsic value of a drug to which it is used is generally described under this heading. It includes the chemical constituents present in the drug. These kinds of drugs are physiologi-cally active.UsesIt includes the pharmaceutical, pharmacological and bio-logical activityobtained from essential oils. The total consumption of perfumery and Chapter-08.indd 97 10/12/2009 4:10:59 PM98 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYflavouring materials in India is about 4,800 metric tonne/annum. The food technology, oral hygiene and pharma-ceutical flavour share around 900 metric tonnes and rest represents perfumery.8.4. UTILIZATION OF AROMATIC PLANTSMentha OilThe oil is obtained by stream distillation of the fresh flowering tops of the plants known as Mentha piperita Linn; Mentha arvensis var-piperascens (Japanese Mint (Family: Labiatae). Mentha oil is commercially cultivated in U.P., Himachal Pradesh, Punjab, Haryana, Jammu and Kashmir and Central India. It contains about 80% of l-menthol. It is also cultivated in Japan, Brazil and California.They are colourless or pale yellow liquid; strong and penetrating odour and taste is pungent and sensation of a cool feeling when air is drawn into the mouth.Mentha oil contains chiefly l-menthol to the extent of 70% in free, as well as, in the form of esters, depending upon variety (like American, Japanese, Indian). American mentha oil contains 80% menthol while Japanese oil contains 70–90%. Other important constituents of the peppermint oil are menthone, menthofuran, Jasmone, menthyl isovalerate, menthyl acetate and several other terpenes derivatives. The other terpene includes 1-limonene, isopulegone, cineole, pinene, camphene, etc., Jasmone and esters are responsible for pleasant flavour, while menthofuran causes resinilication and develops dirty smell.Utilization of mentha oil and derived products 1. Carminative. 2. Spasmolytic. 3. Mild antidiarrhoetic. 4. Aromatic stimulant. 5. Cholagogue. 6. In tooth paste preparations as a taste corrector. 7. The oil is used for flavouring in pharmaceuticals, dental preparation, mouth washes, cough drops, soaps, chewing gum. 8. It is widely used in flatulence, nausea and gastralgia. 9. The oil has mild antiseptic and local anesthetic proper-ties. 10. It is used externally in rheumatism, neuralgia, conges-tive, headache and toothache. 11. The menthol is antipruritic and used on the skin or mucous membrane as counter-irritant, antiseptic and stimulant. Internally, it has a depressant effect on the heart. 12. The menthol is used in food industries such as liquor, soda, syrup, confectionary (candy, chewing gum and chocolate). 13. The menthol is used in cosmetic preparation like shaving cream, tooth paste, lotion, deodorant and aftershave lotion, etc.Eucalyptus OilIt is a volatile oil obtained by steam distillation from fresh leave Eucalyptus globules and other species of eucalyptus (Family: Myrtaceae). It should contain not less than 65% of cineole.It is indigenous to Australia and Tasmania. It is culti-vated in the United States (California), Spain, Portugal and in India. E. citriodora, known as citron scented or lemon scented gum, is grown on large scale basis in Kerala, Tamil Nadu and other states.The odour of oil is aromatic and camphoraceous. It is colourless or pale yellow liquid, having pungent and camphorous taste followed by the sensation of cold. It is soluble in 90% alcohol, fixed oils, fats and in paraffin.Eucalyptus oil chiefly contains cineole, also known as eucalyptol. It also contains pinene, camphene and traces of phellandrene, citronellal, gallo-tannins, methyl ester of p-coumaric acid, and cinnamic acid in combined form. Cit-riodorol (from E. citriodora). It also contains small quantity of butyric, valerenic and caproic aldehyde.OCineole CamphenePhellandreneCH3CH3CH2CH2H C3 CH3CH3Utilization of eucalyptus oil 1. Eucalyptus oil is used as a counter-irritant, an antiseptic and expectorant. 2. Antibacterial and antituberculosis (citriodorol). 3. Diaphoretic. 4. It is used to relieve cough and in chronic bronchitis in the form of inhalation. 5. Solution of eucalyptus oil is used as nasal drops. 6. It is used in infections of the upper respiratory tract, malaria, and certain skin diseases, in ointment for burns and as mosquito repellent. 7. If mixed with an equal amount of olive oil, it is useful as a rubefacient for rheumatism.Geranium OilGeranium oil is obtained by steam distillation of the tender parts of the plants of various species like Pelargonium (Gerani-aceae) (P. graveolens, P. capitatum and P. odoratissium Linn).It is indigenous to South Africa and cultivated in Algeria, Morocco, Spain, France and Italy. Indian geranium oils obtained from other species and is known palmarosa oil.Chapter-08.indd 98 10/12/2009 4:10:59 PM99UTILIZATION OF AROMATIC PLANTS AND DERIVED PRODUCTSAll varieties of geranium generally contain 0.08–0.4% of fragrant volatile oil. Geranium oil contains two types of constituents, i.e. alcohol and esters. The alcohols are β-citranellol and geraniol about 60–70% of the oil. While esters namely geranyl geranyl-tiglate, citranellyl formate and citranellyl acetate contribute about 20–30% oil. Several sesquiterpenes alcohols are also reported in the oil, and are responsible for pleasant fragrance.CH3CH OH2CH3H3CBeta-CitranellolCH3CH OH2CH3H3CGeraniolUtilization of geranium oil 1. As a flavouring agent for creams, lotions, soap, per-fumes and other products. It is also used in alcoholic, nonalcoholic beverages, candy and other dairy products at 0.001%. 2. The oil is used in the treatment of inflammation, with its mild soothing effect. 3. It is a stimulant of the adrenal cortex and can be used to balance the production of androgens which occurs during the menopause. 4. The oil is good insecticide.Vetiver Oil (Khus Oil)It is obtained by steam distillation from roots of the plant of Vetiveria zizanioides Stapf (Family Graminae).The plant is found growing in India, Myanmar, Sri Lanka and East and West Africa. It is cultivated in Indo-nesia, Caribbean Islands, Malaysia, and the United States. In India, it is found abundant in Punjab, Rajasthan, Kerala, Karnataka and Tamil Nadu.Cultivation of vetiver grass is done by sowing the seeds or from slips. A well-drained sandy loam is most suitable for cultivation. The temperature ranging from 25–38°C and rainfall of 100–200 cm are desired. It thrives best in marshy places and humid climate. Planting of slips is done just before the outbreak of monsoon. The distance between two plants and between two rows is approximately 2.5 cm. Proper arrangements for irrigation must be made after rainy season is over. Fertilizers and manures are provided to produce sturdy grass and roots. The grass attains the height of 1–1.5 meters above the guard. When the plant is about 15–18 months of age, the roots are collected by uprooting in dry months of the year. If necessary, digging is done for collection of roots. The drug is slashed, cut into small pieces and used for extraction of oil.Colour of oil is light brown to deep brown or green and odour is characteristics. It is soluble in fixed oil and alcohol.The vetiver oil mainly contains alcohol (45–60%), i.e. vetivenol, vetiverol, and 8–35% ketone namely 3-vetivones. Indian vetiver oil contains khusal, khusitol and khusinol.Utilization of vetiver oil 1. It is used as stimulant, refrigerant, flavouring agent. aromatic, stomachic and in the treatment of prickly heat or itches. 2. It is used as antiseptic, antispasmodic and rubefacient. 3. It is also used in burns, sores and as diaphoretic. 4. It is also used in preparation of sherbet, soap, perfumery and toilet preparations and as a fixative of volatile oils.Sandalwood OilSandal wood oil is obtained by distillation of dried heart wood from the plant Santalum album Linn (Family: San-talaceae).The sandal tree is available in India and Malaya. In India, the trees are available in Tamilnadu, Mysore, Maharastra, Uttar Pradesh, and Madhya Pradesh, Assam, Bihar, Raj-asthan and Gujarat.Sandalof drugs or the diseases in which it is effective.SubstituentsThe drug which is used during non-availability of origi-nal drug is known as substituent. It has the same type of physiological active constituents; however, the percentage quantity of the drug available may be different.AdulterantsWith the knowledge of the diagnostic characters of drugs, the adulterants can be detected. One should have the criti-cal knowledge of substances known to be potential adul-terants. Most of the times the adulterants are completely devoid of physiologically active constituents, which leads in the deterioration of the quality. For example, mixing of buffalo milk with goat milk is substitution, whereas mixing of water in the milk is adulteration. In the first case, goat milk is substitute and in the second case water is adulterant.Chemical TestsThe knowledge of chemical tests becomes more important in case of unorganized drugs whose morphology is not well defined.Chapter-01.indd 9 10/12/2009 3:47:10 PM2.1. INTRODUCTIONPharmacognosy has been basically evolved as an applied science pertaining to the study of all types of drugs of natural origin. However, its subject matter is directed towards the modern allopathic medicine. During the course of develop-ments, many civilizations have raised and perished but the systems of medicines developed by them in various parts of the world are still practised, and are also popular as the alternative systems of medicine. These are the alternative systems in the sense that modern allopathic system has been globally acclaimed as the principal system of medicine, and so all the other systems prevalent and practised in various parts of the world are supposed to be alternative systems. The philosophy and the basic principles of these so called alternative systems might differ significantly from each other, but the fact cannot be denied that these systems have served the humanity for the treatment and management of diseases and also for maintenance of good health. About 80 percent of the world population still rely and use the medicines of these traditional systems.Traditional Chinese medicine in China, Unani system in Greece, Ayurvedic system in India, Amachi in Tibet or more recently Homoeopathy in Germany are these systems of medicine which were once practised only in the respec-tive areas or subcontinents of the world, are now popularly practised all over the world. The World Health Organiza-tion (WHO) is already taking much interest in indigenous systems of medicine and coming forward to exploit the scientific validity of the medicines used since traditions. The revival of great interest in these age-old systems of health care carries much meaning in the present scenarios. The study of these alternative systems is necessary so as to grasp and receive the best out of it to rescue humanity from the clutches of disease. Modern allopathy has developed many sophisticated and costlier diagnostic methodologies which have made it quite exorbitant and beyond the abilities of common man. Many modern synthetic drugs may harm more than they help in curing the disease by its serious toxic effects. On the contrary, traditional medicines are much more preferred for being safe and without harmful effects and comparatively much cheaper than that of allo-pathic medicines. However, one fact must be accepted here that the yelling humanity lastly run towards the modern allopathic treatment, which has developed wonderful tech-niques of diagnosis and highly effective drugs to provide the best and effective treatment than any other system of medicine till date.2.2. TRADITIONAL CHINESE MEDICINE SYSTEMThe use of herbs as medicine is mentioned in China and Japan. The burial that dates back to 168 B.C. consists of corpus of 11 medical works. The development in the field of medicine had took a drastic change by A.D. 25–220 but people were more confident than the earlier period to understand the nature and they believed that the health and the disease depended on the principles of natural order. The first herbal classic written in China was published in the Qin Dynasty (221–206 B.C.) called the Agriculture Emperors Materia Medica. The first plants discovered and used were usually for digestive system disorders (i.e. Da Huang), and slowly as more herbs were discovered the herbs became more useful for an increasing number of ailments, and eventually the herbal tonics were created.Traditional Chinese medicine is based on the principle of Yin and Yang theory. Yang represents the force of light and Yin represents the forces of darkness. According to the yellow emperor, Yin and Yang is the foundation of the entire universe. It underlies everything in creation. It brings about the development of parenthood; it is the root and source of life and death; and it is found with the temples of the gods. In order to treat and cure diseases, one must search for their origins. Heaven was created by the concentration of Yang and the Earth by the concentration of Yin. Yang Alternative Systems of MedicineCHAPTER2Chapter-02.indd 10 10/12/2009 3:49:27 PM11ALTERNATIVE SYSTEMS OF MEDICINEstands for peace and serenity; Yin stands for confusion and turmoil. Yang stands for destruction; Yin stands for conservation. Yang brings about disintegration; Yin gives shape to things. Water is an embodiment of Yin and fire is an embodiment of Yang. Yang creates the air, while Yin creates the senses, which belong to the physical body when the physical body dies; the spirit is restored to the air, its natural environment. The spirit receives its nourishment through the air, and the body receives its nourishment through the senses.Nature has four seasons and five elements. To grant long life, these seasons and elements must store up the power of creation in cold, heat, dryness, moisture and wind. Man has five viscera in which these five climates are transformed into joy, anger, sympathy, grief and fear. The emotions of joy and anger are injurious to the spirit just as cold and heat are injurious to the body. Violent anger depletes Yin; violent joy depletes Yang. When rebellious emotions rise to Heaven, the pulse expires and leaves the body and when joy and anger are without moderation, then cold and heat exceed all measure, and life is no longer secure. Yin and Yang should be respected to an equal extent.When Yang is the stronger, the body is hot, the pores are closed, and people begin to pant; they become boisterous and coarse and do not perspire. They become feverish, their mouths are dry and sore, their stomachs feel tight, and they die of constipation. When Yang is the stronger, people can endure winter but not summer. When Yin is stronger, the body is cold and covered with perspiration. People realize they are ill; they tremble and feel chilly. When they feel chilled, their spirits become rebellious. Their stomachs can no longer digest food and they die. When Yin is stronger, people can endure summer but not winter. Thus, Yin and Yang are alternate. Their ebbs and surges vary, and so does the character of the diseases. The treatment is to harmonize both. When one is filled with vigour and strength, Yin and Yang are in proper harmony.Treatment Every herb has its own properties which include its energy, its flavour, its movement and its related meridians to which it is connected to. The four types of energies are cold, cool, warm and hot. Usually cold or cool herbs will treat fever, thirst, sore throat and general heat diseases. Hot or warm herbs will treat cold sensation in the limbs, cold pain and general cold diseases. The five flavours of herbs are pungent, sour, sweet, salty and bitter. Pungent herbs are generally used to induce perspiration and promote circulation of both blood and Qi. Sour herbs exert three functions: constrict, obstruct and solidify.These herbs are good to stop perspiration, diarrhoea, seminal emission and leucorrhoea. Sweet herbs also exert three main functions: nourishing deficiency, harmonizing other herbs or reduce toxicity, relieve pain and slow the progression of acute diseases. Salty herbs soften hardness, lubricate intestines and drain downward. These herbs are used to treat hard stool with constipation or hard swellings as in diseases like goitre. Bitter herbs induce bowel movements; reduce fevers and hot sensations, dry dampness and clear heat. They can also nourish the kidneys and are used to treat damp diseases. After absorption, herbs can move in four different directions: upward towards the head, downward towards the lower extremities, inward towards the digestive organs or outward towards the superficial regions of the body. Upward-moving herbs are used for falling symp-toms like prolapsed organs. Downward-moving herbs are used to push down up surging symptoms like coughing and vomiting. Outward-moving herbs are used to induce perspiration and treat superficial symptoms that are moving towards the interior of the body. Inward movements of herbs induce bowel movements and promote digestion. Each herb will have a corresponding meridian or meridians to which it will correspond to. For example, herbs that are active against respiratory tract disorders move to the lungs and can be used for asthma or cough.2.3. INDIAN SYSTEMS OF MEDICINEThe WHO estimates that about 80% of the populations living in the developing countries rely exclusively on tra-ditional medicine for their primary health care needs. India has an ancient heritage of traditional medicine. Indian tra-ditional medicine is based on different systems including Ayurveda, Siddha and Unani. With the emerging interest in the world to adopt and study the traditional system and to exploit their potentials based on different health care systems, the evaluation of the rich heritage of the traditional medicine is essential.Almost in all the traditional medicines, the medicinal plants play a crucial role in the traditional medicine. India has a rich heritage of traditional medicine and the tradi-tional health care system have been flourishing for many centuries.In India, the Ayurvedic system of medicine developed an extensive use of medicines from plants dating from at least 1000 B.C. Western medicine continues to show the influence of ancient practices. For example, cardiac glycosides from Digitalis purpurea, morphine from Papaver somniferum, reserpine from Rauwolfia species, and quinine from Cinchona species and artemisinin, an active antimalarial compound from Artemisia annua, etc., show the influence of traditional medicine in Western medicine.Ayurveda—The Indian System of MedicineAyurvedic system of medicine is accepted as the oldest written medical system that is also supposed to be more effective in certain cases than modern therapies. The origin of Ayurveda has been lost in prehistoric antiquity, but Chapter-02.indd 11 10/12/2009 3:49:28 PM12 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYtheir concepts were nurtured between 2500 and 500 B.C. in India.Ayurveda is accepted to be the oldest medical system, which came into existence in about 900 B.C. The word Ayurveda means Ayur meaning life and Veda meaning science. Thus, Ayurveda literally means science of life. The Indian Hindu mythology states four Veda written by the Aryans: Rig Veda, Sam Veda, Yajur Veda and Atharva Veda. The Ayurveda is said to be an Upaveda (part) of Atharva Veda. Charaka Samhita (1900 B.C.) is the first recorded book with the concept of practice of Ayurveda. This describes 341 plants and plant products used in medicine. Sushruta Samhita (600 B.C.) was the next ayurvedic literature that has special emphasis on surgery. It described 395 medicinal plants, 57 drugs of animal origin, 4 minerals and metals as therapeutic agents.Basic principles of ayurvedaAccording to ancient Indian philosophy, the universe is composed of five basic elements or pancha bhutas: prithvi (earth), jal (water), teja (fire), vayu (air) and akash (space). Everything in the universe, including food and the bodies were derived from these bhutas. A fundamental harmony therefore exists between the macrocosm (the universe) and the microcosm (the individual). The Pancha Bhuta theory and the human body: The human body is in a state of continuous flux or dynamic equilibrium. The pancha bhutas are represented in the human body as the doshas, dhatus and malas.There are three doshas in the body. They are vata, pitta and kapha. There are direct equivalents for these three doshas, known as tridoshas. However, the factors responsible for movement and sensation in a single cell/whole body are the representatives of vata; it explains the entire biological phenomena that are controlled by the functions of central and autonomous nervous system. The factors responsible for digestion, metabolism, tissue building, heat production, blood pigmentation, activities of the endocrine glands and energy are the representatives of pitta. The factors respon-sible for strengthening the stomach and the joints, providing firmness to the limbs, and refreshing the sense organs are the representatives of kapha. There are some special areas in the body in which each dosha predominates, namely, the chest for kapha, digestive organs for pitta and the large intestine for vata.The dhatus are the body constituents and form the basic structure of the body; each one having its own functions. The dhatus are seven in number: rasa (food juices), rakta (haemoglobin portion of the blood), mamsa (muscle tissue), medas (fat tissue), asthi (bone tissue), majja (bone marrow) and shukra (semen).Malas are the by-products of the dhatus, partly used by the body and partly excreted as waste matter after the process of digestion is over. These play a supporting role while they are in the body, and when they are eliminated, their supporting role is finished. The useful elements absorbed by the body are retained as prasad (useful matter), while those excreted are known as malas (waste matter). The chief malas are mutra (urine), shakrit (faeces) and sweda (perspira-tion). The doshas, dhatus and malas should be in a state of perfect equilibrium for the body to remain healthy. Any imbalance among these constituents results in ill health and disease.DiagnosisDiagnosis in Ayurveda implies a moment-to-moment moni-toring of the interaction between order (health) and disorder (disease). The disease process is a reaction between the bodily humours (doshas) and tissues (dhatus) and is influenced by the environment.The classical clinical examination in Ayurveda is called ashta sthana pariksha (eight-point diagnosis) and includes an assessment of the state of the doshas as well as various physical signs. The eight-point diagnoses are nadi pariksha (pulse diagnosis), mutra pariksha (urine examination), vata/sparsha (Nervous system assessment), Pitta/drik (assessment of digestive fire and metabolic secretions), kapha/akriti (mucous and mucoid secretions assessment), mala pariksha (stool examination), jihva pariksha (tongue examination) and shabda pariksha (examination of body sounds).TreatmentIn Ayurveda, before starting the treatment, a person’s constitutional type should be determined. Drugs are pre-scribed based on the patient’s body type as well as on what disease or disturbance of the doshas they are suffering from. Everything that might affect the patient’s health, including their activities, the time of the day, and the season should be taken into consideration. In other words, patients are looked at as individuals as well as in relation to their Kaphawater and earthPittafire and waterVataair and etherFig. 2.1 The seats of three doshas: Vata, Pitta and KaphaChapter-02.indd 12 10/12/2009 3:49:28 PM13ALTERNATIVESYSTEMS OF MEDICINEenvironment. Ayurvedic treatment attempts to establish a balance among the bodily humours of vata, pitta and kapha, as well as to improve digestion and elimination of ama (undigested food).Ayurvedic therapy often begins with shodhana (cleansing) in which toxins, emotional or physical, are eliminated or neutralized. Once shodhana is completed, shamana (palliative treatment) is used to reduce the intensity of a disease and balance the disordered doshas. Finally, rasayana (rejuvenation therapy) is used to maintain health and reduce the negative effects of disease.In Ayurveda, vegetable, animal, mineral substances or metals could be used for their healing effects. The metals mentioned as drugs were gold, silver, copper, lead, tin and iron. Along with these substances elements from the earth, like arsenic, antimony, sand and lime, were also used. Earlier, 600 medicinal plants were recorded in Ayurveda, and it has increased to more than 1200 medicinal plants.Properties of herbsAyurvedic herbs are described and classified according to five major properties: rasa (taste), guna (physicochemical properties), veerya (potency), vipaka (postdigestive effect) and prabhava (unique effect of the drug). As the digestive process begins, the food or drug is acted upon by the agnis (various digestive juices) and enzymes.Rasa is divided into six major types: madhura (sweet), amla (sour), lavana (salty), katu (pungent), tikta (bitter), and kashaya (astringent). Each taste is made up of a combination of two of the five basic elements (earth, water, fire, air and ether). Each taste has their own effects on the three bodily doshas (vata, pitta and kapha).Rasa Elements ActionMadhura (sweet) Earth + water Increases kapha, decreases pitta Amla (sour) Earth + fi re Increases kapha/pitta, decreases vata Lavana (salty) Water + fi re Increases kapha/pitta, decreases vata Katu (pungent) Fire + air Increases vata/pitta, decreases kapha Tikta (bitter) Air + ether Increases vata, decreases kapha/pitta Kashaya (astringent) Air + earth Increases vata, decreases kapha/pitta Guna represents the physical aspects of a medicinal sub-stance. There are five major classes of guna, and each class corresponds to one of the major elements (mahabhutas): unctuousness corresponds with water; heaviness with earth; keenness and sharpness with fire; dryness with air; and light with ether. Gunas are generally considered in pairs: cold/hot, wet/dry, soft/hard and stable/unstable, etc.Veerya represents the active principle or potency of a drug. The two divisions are sita veerya (indicates kapha varag) and ushna veerya (indicates pitta varag); vata remains buffer.Vipaka is the quality a substance takes on after it has been acted on by the body (after digestion). The three types of vipaka are madhura (increases kapha), sour (increases pitta) and katu (increases vata). The type of food responsible for madhura, sour and katu are carbohydrates, proteins and fats, respectively.Prabhava is the activity or influence of a drug in the body. The drugs may have the same rasa, guna, veerya and vipaka but the prabhava may be different due to the chemi-cal composition.Branches of ayurvedaAyurveda maintains that there is a definite relationship between illness and the metaphysical state of an individual. Its approach to medical treatment is to focus on the person rather than the disease.Ayurveda has eight branches: Kaya Chikitsa (Medicine), Salya Chikitsa (Surgery), Salakya Chikitsa (ENT treatment), Bala Chikitsa (Paediatric treatment), Jara Chikitsa (treatment related to genetics), Rasayana Chikitsa (treatment with chemicals), Vajikarama Chikitsa (treatment with rejuvenation and aphrodisiacs), Graham Chikitsa (planetary effects) and Visha Chikitsa (toxicology).Tibetan system of medicine which is the main stay of the majority of Tibetan people not only in India, but in neighbouring countries too was developed out of Ayurveda, or was influenced by it. Researches in traditional medicine have confirmed the efficacy of most of the natural sub-stances used by the practitioners of Ayurveda. The principle, treatment and philosophy of Ayurveda are one of the best systems that fulfill the needs of human beings. It has so many good prescriptions without many side effects. Thus, Ayurveda formulates the holistic approach of treatment by subjecting the body as a whole giving least importance to rogabalam. This may be the reason for time-consuming treatment in Ayurveda, but the results last long.2.4. SIDDHA SYSTEM OF MEDICINESiddha medicine is practised in Southern India. The origin of the Tamil language is attributed to the sage Agasthya, and the origin of Siddha medicine is also attributed to him. Before the Aryan occupation of the Sind region and the Gangetic plain, there existed in the southern India, on the banks of the river Cauvery and Tamirapani, a civilization which was highly organized. 1. This civilization has a system of medicine to deal with problems of sanitation and treatment of diseases. This is the Siddha system of medicine. The therapeutics of Siddha medicines consists mainly of the use of metals and minerals whereas in the earlier Ayurveda. 2. There is mention of mercury, sulphur, copper, arsenic and gold used as therapeutic agents.Chapter-02.indd 13 10/12/2009 3:49:28 PM14 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYPrinciple of Siddha system of medicineThe universe consists of two essential entities: matter and energy. The Siddhas call them Siva (male) and Shakti (female, creation). Matter cannot exist without energy inherent in it and vice versa. The two coexist and are inseparable. They are the primordial elements (bhutas), and are not to be confused with modern chemistry. Their names are munn (solid), neer (fluid), thee (radiance), vayu (gas) and aakasam (ether). These five elements (bhutas) are present in every substance, but in different proportions. Earth, water, fire, air and ether are manifestations of five elements.The human being is made up of these five elements, in different combinations. The physiological function in the body is mediated by three substances (dravyas), which are made up of the five elements. They are vatham, pitham and karpam. In each and every cell of the body these three doshas coexist and function harmoniously. The tissues are called dhatus. Vatham is formed by aakasam and vayu. Vatham controls the nervous actions such as movement, sensation, etc. Pitham is formed by thee and controls the metabolic activity of the body, digestion, assimilation and warmth, etc. Karpam is formed by munn and neer and controls stability. When their equilibrium is upset, disease sets in.Tridoshas according to Siddha medicineThe tridoshas are involved in all functions of the body, physical, mental and emotional. 1. Vatham:C � haracteristic is dryness, lightness, coldness and motility.Formed by � aakasam and vayu, controls the nervous action that constitute movement, activity, sensation, etc. Vatham predominates in the bone.Vatham � predominates in first one-third of life when activities, growth, sharpness of function of sense are greater. 2. Pitham:Heat—mover of the nervous force of the body. �Formed by � thee, controls the metabolic activity of the body, digestion, warmth, lustre, intellect, assimilation, etc. Pitham predominates in the tissue blood.Pitham � predominates in the second one third of life. 3. Karpam:Smoothness, firmness, viscidity, heaviness. �Formed by � munn and neer, controls the stability of the body such as strength, potency, smooth working of joints. Karpam predominates in other tissues.Karpam � predominates in the last one-third of life. Diminishing activity of various organs and limbs.The seven dhatus are as follows: 1. Rasa (lymph). 2. Kurudhi (blood). 3. Tasai (muscle). 4. Kozhuppu (adipose tissue).5. Elumbu (bone). 6. Majjai (marrow). 7. Sukkilam and artavam (male and female hormones).Method of treatmentThe treatments for the imbalance of the Tridoshas are made up of the five elements. The drugs are made up of the five elements. By substituting a drug of the same constituents (guna), the equilibrium is restored. The correction of the imbalance is made by substituting the drug, which is pre-dominately of the opposite nature. An example of vatham imbalance is cold, dry; thus the treatment will be oily and warmth. For inactivity of limbs, massage and activity are prescribed. If pitham dosha is increased, warmth is produced; to decrease pitham, sandalwood is administered, internally or externally because of its cold characteristics.Five type of vayu are as follows: 1. Prana: located in mouth and nostrils (inhaled); aids ingestion. 2. Apana: located at anal extremity (expelled); elimination, expulsion. 3. Samana: equalizer, aids digestion. 4. Vyana: circulation of blood and nutrients. 5. Udana: functions in upper respiratory passages.Siddha pharmacyMercury: Mercury occupies a very high place in Siddha medicine. It is used as a catalytic agent in many of its medicines. When mercury is used, it is used in combina-tion with sulphur. The addition of sulphur is to control the fluidity of mercury—this converts to mercuric sulphite which is insoluble in mineral acids.Siddhas used five forms of mercury: 1. Mercury metal—rasam. 2. Red sulphide of mercury—lingam. 3. Mercury chloride—veeram. 4. Mercury subchloride (mercury chloride)—pooram. 5. Red oxide of mercury—rasa chenduram. Ordinary rasa chenduram (red oxide of mercury) is a poison, but when processed as poorna chandrodayam according to Siddha practice, it becomes ambrosia.Classifications of Siddha medicine: 1. Uppu (Lavanam): Drugs that dissolve in water and decrepitated when put into fire giving off vapours (water soluble inorganic compounds). There are 25 varieties and are called kara-charam, salts and alkalis. 2. Pashanam: Drugs that do not dissolve in water but give off vapour when put into fire (water insoluble inorganic compounds).Chapter-02.indd 14 10/12/2009 3:49:28 PM15ALTERNATIVE SYSTEMS OF MEDICINE 3. Uparasam: Drugs that do not dissolve in water (chemi-cals similar to Pashanam but differing in their actions) such as mica, magnetic iron, antimony, zinc sulphate, iron pyrites, ferrous sulphate. 4. Loham: Metals and minerals alloys (water insoluble, melt in fire, solidify on cooling) such as gold, silver copper, iron, tin and lead. 5. Rasam: Drugs that are soluble (sublime when put in fire, and changes into small crystals), such as mercury amalgams and compounds of mercury, arsenic. 6. Gandhakam: Sulphur insoluble in water, burns off when put into fire. 7. Ratnas and uparatnas: Thirteen varieties are described, such as coral, lapis-lazuli, pearls, diamonds, jade, emerald, ruby, sapphire, opal, vaikrantham, rajavantham, spatikam harin mani.The common preparations of Siddha medicines are: 1. Bhasma (Calcined metals and minerals). 2. Churna (powders). 3. Kashaya (decoctions). 4. Lehya (confections). 5. Ghrita (ghee preparations) and taila (oil prepara-tions). 6. Chunna (metallic preparations which become alka-line). 7. Mezhugu (waxy preparations). 8. Kattu (preparation that are impervious to water and flames.Sulphur: Calcined sulphur or red oxide of sulphur can be obtained by solidifying it first by the Siddha method of purification. In small doses, it conserves the body, and it is diaphoretic and alterative. Therapeutic ally is used as both external and internal remedy against skin diseases, rheu-matic arthritis, asthma, jaundice and blood poisoning.Arsenic: As per Siddha kalpa, purified and consolidated arsenic is effective against all fevers, asthma and anaemia.Gold: It is alterative, nervine tonic, antidote to poison and a powerful sexual stimulant. Very little is absorbed in the system. Care is taken to see that calcinations of gold is freed from metallic state and lustre to ensure safe absorption in the system.Thus, these drugs and metallic minerals can be screened for its antiviral, immune stimulant and immuno-modulator activity. As HIV negative people have taken Kalpha drugs for rejuvenation and long life, it is believed that if Kayakapla therapy is thoroughly investigated using modern parameters, it might lead one to find whether these drugs could be used in preventative or curative benefits in AIDS or other diseases.2.5. UNANI SYSTEM OF MEDICINEUnani system of medicine is originated in Greece by the Greek philosopher, physician Hippocrates (460–377 B.C.), who freed medicine from the realm of superstition and magic, and gave it the status of science. The theoretical framework of Unani medicine is based on the teachings of Hippocrates. After him, a number of other Greek scholars followed the system considerably. Among them Galen (131–212 A.D.) was the one to stabilize its foundation, on which Arab physicians like Raazes (850–925 A.D.) and Avicenna (980–1037 A.D.) constructed an imposing edifice. Unani medicine got its importance among the other systems of traditional medicine in Egypt, Syria, Iraq, Persia, India, China and other Middle East and Far East countries. In India, Arabs introduced Unani system of medicine, and soon it enriched in India. When Mongols ravaged Persian and central Asian cities, scholars and physicians of Unani medicine fled to India. The Delhi Sultans, the Khiljis, the Tughlaqs and the Mughal Emperors provided state patronage to the scholars and even enrolled some as state employees and court physicians. During the 13th and 17th century, Unani medicine was firmly rooted in India by Abu Bakr Bin Ali Usman Kasahani, Sadruddin Damashqui, Bahwabin Khwas Khan, Ali Geelani, Akabl Arzani and Mohammad Hoshim Alvi Khan.Unani considers the human body to be made up of seven components. Arkan (elements), mizaj (temperaments), aklath (humours), anza (organs), arawh (spirits), Quo (faculties) and afal (functions), each of which has close relation to the state of health of an individual. A physician takes into account all these factors before diagnosing and prescribing treatment.Unani medicine is based on the Greece philosophy. According to Basic Principles of Unani, the body is made up of the four basic elements, i.e. Earth, Air, Water and Fire, which have different Temperaments, i.e. Cold, Hot, Wet and Dry. After mixing and interaction of four ele-ments, a new compound having new temperament comes into existence, i.e. Hot Wet, Hot Dry, Cold Wet and Cold Dry. The body has the simple and compound organs, which got their nourishment through four humours, i.e. blood, phlegm, yellow bile and black bile. The humour also assigned temperament as blood is, i.e. hot and wet; Phlegm is cold and hot, yellow bile is hot and dry and black bile is cold and dry. Health is a state of body in which there is equilibrium in the humours and functions of the body are normal in accordance to its own temperament and the environment.When the equilibrium of the humours is disturbed and functions of the body are abnormal, in accordance to its own temperament and environment, that state is called disease. Unani medicine believes in promotion of health, prevention of diseases and cure. Health of human is based on the six essentials (Asbabe Sitta Zaroorya), if these are followed health is maintained; otherwise, there will be diseases.Six essentials are atmospheric air, drinks and food, sleep and wakefulness, excretion and retention, physical activity and rest and mental activity and rest.Chapter-02.indd 15 10/12/2009 3:49:28 PM16 TEXTBOOK OF PHARMACOGNOSY AND PHYTOCHEMISTRYDiagnosisDiseases are mainly diagnosed with the help of pulse (nabz), physical examination of the urine and stool. Also, patients are examined systematically to make the diagnosis easy