Pharmacognosy_and_Pharmacobiotechnology.pdf

 This page intentionally left blank Copyright © 2007, 2003 , New Age International (P) Ltd., Publishers Published by New Age International (P) Ltd., Publishers All rights reserved. No part of this ebook may be reproduced in any form, by photostat, microfilm, xerography, or any other mea...

 This page intentionally left blank Copyright © 2007, 2003 , New Age International (P) Ltd., Publishers Published by New Age International (P) Ltd., Publishers All rights reserved. No part of this ebook may be reproduced in any form, by photostat, microfilm, xerography, or any other means, or incorporated into any information retrieval system, electronic or mechanical, without the written permission of the publisher. All inquiries should be emailed to [email protected] ISBN (13) : 978-81-224-2915-2 PUBLISHING FOR ONE WORLD NEW AGE INTERNATIONAL (P) LIMITED, PUBLISHERS 4835/24, Ansari Road, Daryaganj, New Delhi - 110002 Visit us at www.newagepublishers.com  Dedication Dedicated with humility and reverence to the fond memory of beloved parents who encouraged and flared passion in me to learn more always. Thanks Wish to thank Leena, Ashish and Abhijeet for their boundless patience and eternal understanding during completion of this text. Love Aditi, our grand-daughter, who brought in an eternal saga of love, and energised our inspirations to perform better.  This page intentionally left blank  Preface to the Second Edition Overwhelming appreciation, whole-hearted acceptance, and qualified success of the First Edition of the textbook entitled ‘Pharmacognosy and Pharmacobiotechnology’ extended by the postgraduate students specializing in Pharmacognosy and Phytochemistry, Biotechnology, Pharmaceutical Chemistry, Chemistry of Natural Products; besides the enormous undergraduate students in Bachelor of Pharmacy programmes in all the reputed Pharmacy Degree Colleges not only in India but also abroad are quite encouraging. Exclusively based upon the commendable comments and constructive criticisms received from various academic colleagues across the country the author has meticulously presented this entirely revised and duly expanded Second Edition. Moreover, the reading text material has been updated thoroughly, various biosynthetic pathways modified adequately, chemical structures and tabular contents enumerated more explicitly. Besides, the critical definitions, important statements, terminologies, names of chemical constituents have been duly highlighted so as to facilitate its readers to comprehend them accurately. Tremendous achievement and advance in the different segments of highly sophisticated ‘Research Techniques’ solely based on PC-modulated modern analytical techniques helped not only to clarify the rather complex chemical structures of unravelled chemical constituents from Natural Products, but also established precisely the plethora of ‘Biosynthetic Pathways’ dominating the plant kingdom. The present textbook essentially comprises of nearly sixty ‘biosynthetic routes’ of predominantly important natural chemical entities, such as: alkaloids, antibiotics, glycosides, marine-derived drug substances, and terpenoids. It is, however, pertinent to add here that certain extremely preliminary aspects to the related pharmacognostical characteristic features of ‘Natural Plant Products’, namely: morphological structures, adulterants used in herbal products, habitats, method of cultivation, geographical distribution etc., have been expunged from the text, to which the students invariably obtain sufficient exposure in the early stages of their systematic curriculum follow up. The Second Edition essentially comprises of five additional chapters, namely: (i) Nutraceuticals, (ii) Enzymes and Protein Drugs, (iii) Biomedicinals from Plant Tissue Cultures, (iv) Hi-Tech Products from Plant Sources, and (v) Indian Traditional Herbal Drugs, i.e., chapter-11 through chapter-15. The judicious and thoughtful inclusion of these five chapters would certainly expose the PG/UG students of the aforesaid disciplines to an exceptionally solid platform in the scientific pursuit of their knowledge. The author feels convinced and earnestly believes that the Second Revised and Expanded Edition of Pharmacognosy and Pharmacobiotechnology shall largely fulfil the much needed value-added substantial text materials.  viii PREFACE TO THE SECOND EDITION It is hoped that Pharmacognosy and Pharmacobiotechnology will continue to enjoy its popularity amongst the august teaching fraternity, brilliant students, herbal practitioners, pharmacognosists, herbal chemists, phytochemists, biotechnologists, and above all the researchers who would like to make an illustrious career in their respective professional discipline in the New Millennium. Finally, the author wishes to place on record his deep sense of gratitude to Shri Saumya Gupta M.D., and the entire professionals of New Age International (P) Limited Publishers, for their excellent support to bring out this edition in such a short-span. Gurgaon Dr. Ashutosh Kar  Preface to the First Edition Etymological evidences reveal that ‘pharmacognosy’ refers to the knowledge (from the Greek gnosis) of drug (Pharmacon) substances. Pharmacognosy may also be referred to as—‘Study of sources, and chemical and physical properties of drugs’. In the present context pharmacognosy, since Dioscorides’s treatise, has spread its tentacles to investigations of a wider section of naturally occurring materials essentially comprised of plants, animals, substances originated from microorganisms and even biotechnology and genetically engineered entities. Jean Bruneton, the famous French pharmacognosist, describes pharmacognosy as—‘Study of starting materials and substances intended for therapeutics, and of biological origin, in other words obtained from plants, animals, or by fermentation from microorganisms’. Since the past two centuries the identification, isolation and characterization of naturally occurring substances across the world have been accomplished by the concerted efforts through a central preoccupation of innumerable research chemists and biological scientists. In the recent past, the world has witnessed an overwhelming progress towards intensification of interest more so in natural products from the herbal-based pharmaceutical industries with the epoch-making discoveries of extremely useful new drugs, namely, taxol, artemisinin ginsengoside Rg1 ginkolide A, doxorubicin and the like, from the nature’s natural reserves. The other predominant aspect is ‘pharmacobiotechnology’, an area that encompasses the intricate production of natural-product-drug substances on the basis of the copious volumes of scientific evidences amalgamated with tremendous progress and breakthroughs particularly in the fields of ‘biotechnology’ and ‘molecular biology’. It is indeed an altogether newer frontier charged with innovative ideas and approaches in modern-drug-discovery scenario to modify and improve upon the quality of life of human beings on this planet. Therefore, in the present textbook, an earnest attempt has been made to deal with the newest drugs on one hand and the oldest ones on the other in a very systematic and lucid manner with a strong conviction that these all belong to the natural origins. Interestingly, the last five decades have witnessed a quantum jump in relevant and useful publications especially with regard to books pertaining to medicinal plants, medicinal herbs, biologically active natural products, phytochemistry of medieval plants, alternative medicine; besides herbal and botanical remedies for commoners. It is, however, pertinent to mention about the legitimate exposure vis-a-vis the in depth knowledge of the various aspects of medicinal plants well within the broader limits of pharmacognosy—a professional discipline widely recognised not only amongst the pharmacy and medical herbalism academic programmes but also of utmost significance to non- medical professionals. The present text essentially comprised of ten chapters, namely: introduction to phytochemistry, pharmacobiotechnology, carbohydrates, glycosides, terpenoids, phenylpropanoids, alkaloids, bitter  x PREFACE TO THE FIRST EDITION principles, antibiotics, and drug molecules of marine organisms. Keeping in view the intensive and remarkable progressive advances accomplished in phytochemical and technological research, it was thought worthwhile to make adequate coverage of pharmacognosy essentially needed not only for the pharmacy degree syllabuses in general but also for the professional class in particular. The drugs have been classified on a unique broad-based, widely accepted and literature-supported manner. These are carefully selected and arranged in each chapter, organized on the strong footing of chemical relationships, their biosynthetic approach, thereby elaborating sufficient basic fundamentals for the better advanced knowledge and vivid understanding of the wonderful natural products as ‘drugs’. Each individual drug belonging to various groups dealt with in the present textbook has been carefully selected based on its academic merit, status and relevance. It has been treated in a most scientific and methodical manner essentially consisting of the following highlights, namely: latest classification, authentic nomenclature, synonym(s), biological source(s), chemical structure, chemical name, molecular formula, isolation or preparation methods, characteristic features, identification test(s), derivatization, characteristics of derivatives, therapeutic uses, and biosynthetic pathways, wherever applicable. A number of important classes of compounds and their relevant features have been summarized in tabular forms selected figures in the text have been incorporated at appropriate places to make the ensuing subject matter more easily understandable to its readers biosynthetic pathways have been explicitly dealt with. The text contains more than one thousand chemical structures of drugs and their intermediates, more than fifty biosynthetic pathways and about fifteen figures. Bearing in mind the extraordinary pace and appreciable momentum gathered by the global pharmaceutical market, followed by an encouraging number of newer drug companies joining the modern trend of market demands, there exists an enormous scope in phytochemical research and development efforts. The world-wide intensive quest for newer, safer and effective drugs from natural products is not confined only to the terrestrial plants from tropical rain forests and to animals, but also to the plants and microorganisms occurring in deep oceans surrounding this earth. It is earnestly believed that in the present textbook the modern concepts of pharmacognosy shall fulfil the necessary requirements of undergraduate and graduate students of various universities in India and other developing nations. Those who intend to continue their research in medicinal plants and desire to establish a strong base in the production of herbal-drug industries may also find this compilation equally informative and useful. Addis Ababa Dr. Ashutosh Kar  Contents Preface to the Second Edition vii Preface to the First Edition ix 1. Introduction 1 1.1 Pharmacognosy—A Brief History 1 1.2 Importance of Natural Drug Substances 5 1.2.1 Serve as Extremely Useful Natural Drugs 5 1.2.2 Provide Basic Compounds Affording Less Toxic and More Effective Drug Molecules 10 1.2.3 Exploration of Biological–Active–Prototypes towards Newer and Better Synthetic Drugs 10 1.2.4 Modificaton of Inactive Natural Products by Suitable Biological/Chemical Means into Potent Drugs 13 1.3 Natural Drugs Substances: Cultivation and Production 15 1.3.1 Plant Products 15 1.3.2 Cell-Culture Techniques 16 1.3.3 Microbial Metabolites 16 1.3.4 Animal Derivatives 18 1.4 Phytochemistry 19 1.4.1 Constituents 21 2. Pharmacobiotechnology 41 2.1 Introduction 41 2.2 Theory 42 2.2.1 Mutation, Crossing-over and Recombinant of Meiosis 43 2.2.2 Third Revolution in Modern Medicine 43 2.2.3 Genetic Code 44 2.2.4 Specific Sets of Genes in Each Individual Organ 44 2.2.5 Reverse Transcriptase (RT) 44 2.2.6 3D-Proteins 45 2.2.7 From Nervous System to Immune System 45 2.2.8 Body’s Defence Mechanism 46 2.2.9 PCR–in Forensic & Research 46 2.2.10 DNA–in Metabolic Pathways 46 2.2.11 Recombinant Vaccination Vector 46 2.2.12 OKT3–Monoclonal Antibody 47 xii CONTENTS 2.3 Important Means in Biotechnology 47 2.3.1 Recombinant DNA (rDNA) 47 2.3.2 Restriction Enzymes 47 2.3.3 DNA–Ligase 48 2.3.4 Cloning Vector 48 2.3.5 Hybridization Probes 49 2.3.6 Cloning Process 50 2.4 Recombinant Proteins 58 2.4.1 Bacterial Systems 58 2.4.2 Glycosylation 59 2.4.3 Mammalian Tissue Culture Expression Systems 60 2.5 Biotechnology Vs Modern Pharmacy Practice 60 2.5.1 Human Proteins as Drugs 61 2.5.2 New Drug Classes 63 2.5.3 Vaccines 64 2.5.4 New Immunodiagnostic Agents 66 2.5.5 DNA Probes and RFLP Analysis 68 2.5.6 Enzyme Linked Immunosorbant Assay (ELISA) 69 2.6 Biotechnology Based Pharmaceuticals for the Millennium 71 2.6.1 Genetically Engineered Vaccine 72 2.6.2 Gene Splicing and DNA Recombinant Procedures 73 2.6.3 Antibodies in Biotechnology 75 2.6.4 Gene Therapy 77 2.6.5 3D Picture of the ‘Lock’ and ‘Keys’ 78 2.7 Biotechnology and Modern Drug Discovery 79 2.7.1 Approved Medicines 79 2.7.2 Medicines Under Development 80 2.7.3 Human Clone 80 2.8 Biotechnology: Some Thought Provoking Newer Ideas 82 2.8.1 Potato Vaccine 82 2.8.2 Functional Food Revolution 82 3. Carbohydrates 84 3.1 Introduction 84 3.2 Classification 86 3.2.1 Homoglycans 86 3.2.2 Heteroglycans 100 3.3 Carbohydrate Biogenesis 119 4. Glycosides 122 4.1 Introduction 122 4.1.1 O-Glycosides 125 4.1.2 S-Glycosides 125 4.1.3 N-Glycosides 125 4.1.4 C-Glycosides 126  CONTENTS xiii 4.2 Classification 127 4.2.1 Anthracene Glycosides (or Anthraquinone Glycosides) 127 4.2.2 Phenol Glycosides 139 4.2.3 Steroid Glycosides 144 4.2.4 Flavonoid Glycosides 157 4.2.5 Coumarin and Furanocoumarin Glycosides 168 4.2.6 Cyanogenetic Glycosides 173 4.2.7 Thioglycosides 179 4.2.8 Saponin Glycosides 182 4.2.9 Aldehyde Glycosides 195 4.2.10 Bitter Glycosides 196 4.2.11 Miscellaneous Glycosides 200 4.3 Biosynthesis of Glycosides 202 4.3.1 Biosynthesis of Anthracene Glycosides 203 4.3.2 Biosynthesis of Phenol Glycosides 204 4.3.3 Biosynthesis of Steroid Glycosides 204 4.3.4 Biosynthesis of Flavonoid Glycosides 204 4.3.5 Biosynthesis of Coumarin and Furanocoumarin Glycosides 205 4.3.6 Biosynthesis of Cyanogenetic Glycosides 207 4.3.7 Biosynthesis of Thioglycosides 209 4.3.8 Biosynthesis of Saponin Glycosides 209 4.3.9 Biosynthesis of Aldehyde Glycosides 210 4.4 Profile of Glycosides in Natural Plant Sources 210 5. Terpenoids 215 5.1 Introduction 215 5.2 Classification 218 5.2.1 Monoterpenoids 218 5.2.2 Sesquiterpenoids 228 5.2.3 Diterpenoids 233 5.2.4 Triterpenoids 236 5.2.5 Tetraterpenoids and Carotenoids 238 5.2.6 Volatile Oils (or Essential Oils) 240 5.2.7 Resins and Resin Combinations 306 5.2.8 Oleoresins 323 5.2.9 Oleo-Gum-Resins 328 6. Phenylpropanoids 340 6.1 Introduction 340 6.2 Classification 340 6.2.1 Hydroxycinnamic Acids 341 6.2.2 Phenylpropenes 344 6.2.3 Coumarins 345 6.2.4 Abridged Phenylpropanoids 354 xiv CONTENTS 6.2.5 Biphenylpropanoid Derivatives 361 6.2.6 High Molecular Weight Phenylpropanoids 366 6.3 Biosynthesis of Phenylpropanoids 369 7. Alkaloids 372 7.1 Introduction 372 7.1.1 Nomenclature 374 7.1.2 Occurrence and Distribution in Different Organ’s of Plant 374 7.1.3 Site of Formation of Alkaloids in Plants 377 7.1.4 Function of Alkaloids in Plants 377 7.1.5 Isomerism 378 7.1.6 General Characteristics of Alkaloids 380 7.1.7 General Methods of Extraction and Isolation of Alkaloids 389 7.2 Classification of Alkaloids 395 7.2.1 Alkaloids Derived from Amination Reactions 401 7.2.2 Alkaloids Derived from Anthranilic Acid 427 7.2.3 Alkaloids Derived from Histidine 436 7.2.4 Alkaloids Derived from Lysine 441 7.2.5 Alkaloids Derived from Nicotinic Acid 454 7.2.6 Alkaloids Derived from Ornithine 461 7.2.7 Alkaloids Derived from Tyrosine 475 7.2.8 Alkaloids Derived from Tryptophan 495 7.3 Alkaloids in Tissue Cultures 542 7.4 Alkaloids in Chemosystematics 543 8. Bitter Principles 547 8.1 Introduction 547 8.2 Classification of Bitter Principles 547 8.2.1 Phenolic Bitter Principles 548 8.2.2 Lactone Bitter Principles 550 8.2.3 Chromone Bitter Principles 553 8.2.4 Coumarin Bitter Principles 556 8.2.5 Coumarone Bitter Principles 559 8.2.6 Miscellaneous Bitter Principles 561 9. Antibiotics 568 9.1 Introduction 568 9.2 Antibiotic Development 569 9.2.1 Quest for New Antibiotics 569 9.2.2 Large-Scale Production 571 9.3 Classification of Antibiotics 579 9.3.1 Aminoglycosides 579 9.3.2 Anthracyclines 590 9.3.3 Cephalosporins 596 9.3.4 b-Lactams 611  CONTENTS xv 9.3.5 Lincosamides 616 9.3.6 Macrolides 618 9.3.7 Penicillins 625 9.3.8 Polypeptide Antibiotics 641 9.3.9 Tetracyclines 649 9.3.10 Miscellaneous Antibiotics 657 10. Drug Molecules of Marine Organisms 695 10.1 Introduction 695 10.2 Classification of Drug Molecules of Marine Organisms 696 10.2.1 Cytotoxic/Antineoplastic Agents 696 10.2.2 Cardiovascular Active Drugs 701 10.2.3 Marine Toxins 709 10.2.4 Antimicrobial Drugs 716 10.2.5 Antibiotic Substances 718 10.2.6 Antiinflammatory and Antispasmodic Agents 720 10.2.7 Miscellaneous Pharmacologically Active Substances 721 10.3 Marine Natural Products: An Upgradation Profile 726 10.3.1 Microbial Transformations 726 10.3.2 Puupehenone: Semisynthetic Analogues 729 10.4 Summary 733 11. Nutraceuticals 735 11.1 Introduction 735 11.2 Phytochemicals as Nutraceuticals 737 11.2.1 Terpenoids (or Isoprenoids) 738 11.2.2 Non-Carotenoid Terpenoids 742 11.2.3 Polyphenolics [or Polyphenol Extracts] 744 11.2.4 Phenolic Acids 751 11.2.5 Non-Flavonoid Polyphenolics 753 11.2.6 Glucosinolates [or Thioglucosides] 755 11.2.7 Thiosulphinates [or Cysteine Sulphoxides] 759 11.2.8 Phytosterols 760 11.2.9 Anthraquinones 761 11.2.10 Glucosamine [Synonym: Chitosamine;] 763 11.2.11 Octacosanol [Synonym: Octacosyl Alcohol] 764 11.2.12 Carnitine [Synonym: g-Trimethyl-b-hydroxybutyrobetaine;] 765 11.2.13 Capsaicin [Synonyms: Axsain; Mioton; Zacin; Zostrix;] 767 11.2.14 Piperine 768 11.2.15 Chlorophyll 768 11.2.16 Pectin 770 11.2.17 Dominant Phytochemical Pigments 770 11.2.18 Tocotrienols and Tocopherols 770 11.2.19 a-Lipoic Acid and Ubiquinones 771 xvi CONTENTS 11.3 Contemporary Nutraceuticals 772 11.3.1 Spiruline 773 11.3.2 Broccoli 773 11.3.3 Aloe Vera Gel and Aloe Juice 774 11.3.4 Soyfoods 776 11.3.5 Omega-3 Fatty Acids 776 11.3.6 Pomegranate Juice 777 11.3.7 Walnuts 777 11.3.8 Certified Organic Mushroom Nutrace 777 12. Enzyme and Protein Drug Substances 779 A. Enzyme as Drug Substances 779 12.1 Introduction 779 12.2 Enzyme Variants 782 12.3 Enzymes of Pharmaceutical Relevance and Utility 783 12.4 Brief Description of Enzymes Used as Drugs 784 12.4.1 Bromelain 784 12.4.2 Chymotrypsin 784 12.4.3 Collagenase 784 12.4.4 Deoxyribonuclease [DNase] 785 12.4.5 Fibrinolysin 785 12.4.6 Hyaluronidase 785 12.4.7 Muramidase 785 12.4.8 Papain 786 12.4.9 Pancreatin 786 12.4.10 Pancrealipase 787 12.4.11 Pepsin [Greek: Pepsis = digestion] 787 12.4.12 Rennin [or Chymosin] 787 12.4.13 Seratiopeptidase 787 12.4.14 Streptokinase 788 12.4.15 Urokinase 788 12.4.16 L-Asparaginase 789 B. Protein as Drug Substances 789 12.5 Introduction 789 12.6 Protein Variants 790 12.7 Brief Description of Proteins Used as Drugs 791 12.7.1 Complement Protein (Complement Factor C-3) [Latin; Complere = to Complete] 791 12.7.2 Gelatin [Latin: Gelatina = Gelatin] 792 12.7.3 Collagen [Synonym: Ossien]: (Greek: kolla = glue, + gennan = to produce) 792 12.7.4 Casein [Latin: caseus = cheese] 793 12.7.5 Lectins [Synonyms: Agglutinins; Affinitins; Phasins; Protectins;] 794  CONTENTS xvii 12.7.6 Yeast 794 12.7.7 Thaumatin [Synonym: Talin;] 795 13. Biomedicinals From Plant-Tissue Cultures 797 13.1 Introduction 797 13.2 Profile of Plant-Tissue Cultures 800 13.2.1 Type of Cultures 800 13.2.2 Composition of Culture Medium 801 13.2.3 Surface Sterilization of Explants 803 13.2.4 Preparation of Tissue Cultures 804 13.3 Biomedicinals in Plant-Tissue Cultures 805 13.3.1 Secondary Metabolites 806 13.3.2 Usefulness of Secondary Metabolites 808 13.3.3 Secondary Metabolites in Chemosystematics 809 13.3.4 Newer Products Developed 810 13.4 Bioproduction of Commendable Secondary Metabolites 811 14. Hi-Tech Products from Plant Sources 814 14.1 Introduction 814 14.2 High Throughput Screening (HTS) 815 14.2.1 HTS and Bioassays 816 14.2.2 Access to Plants vis-a-vis Natural Source Materials 817 14.2.3 HTS and Selection for Plant Materials 818 14.2.4 Identification Process of Plants for Targeted Sets 819 14.2.5 Dereplication and Isolation of Active Compounds 820 14.3 Success of HTS of Plant Source Materials for New Lead Chemical Entities 820 14.3.1 Use of MS for Identification of Potent Biologically Active and Important Drug Molecules 821 14.4 Hi-Tech Products 822 14.4.1 Genistein [Syn. Genisteol; Prunetol;] 822 14.4.2 Camptothecin 823 14.4.3 Rhein [Syn: Monorhein; Rheic Acid; Cassic Acid; Parietic Acid; Rhubarb Yellow] 823 14.4.4 Taxanes 824 14.4.5 Homoharringtonine (HHT) 824 15. Indian Traditional Herbal Drugs 827 15.1 Introduction 827 15.2 Indian Traditional Herbal Drugs 828 15.2.1 Cardiovascular Drugs 828 15.2.2 Immunomodulators and Adaptogens 830 15.2.3 Antidiabetic Drugs 830 15.2.4 Antineoplastic Drugs 831 15.2.5 Antiviral Drugs 832 Index 835  This page intentionally left blank 1 Introduction z Pharmacognosy—A Brief History z Phytochemistry z Importance of Natural Drug Substances z Further Reading References z Natural Drugs Substances: Cultivation and Production 1.1 PHARMACOGNOSY—A BRIEF HISTORY ‘Pharmacognosy’—has been coined by the merger of two Greek words Pharmakon (drug) and Gnosis (knowledge) i.e., the knowledge of drugs. The nomenclature—‘Pharmacognosy’ was used first and foremost by C.A. Seydler, a medical student in Halle/Saale, Germany, who emphatically employed Analetica Pharmacognostica as the main title of his thesis in the year 1815. Besides, further investigations have revealed that. Schmidt has made use of the terminology ‘Pharmacognosis’ in the monograph entitled Lehrbuch der Materia Medica (i.e., Lecture Notes on Medical Matter) which dates back to 1811, in Vienna. This compilation exclusively deals with the medicinal plants and their corresponding characteristics. It is indeed quite interesting to observe that our ancients were duly equipped with a vast, in- depth and elaborated knowledge of plethora of drugs from the vegetable origin but unfortunately they possessed a scanty knowledge with regard to the presence of chemically pure compounds in most of them. Camphor found its enormous use in the treatment and cure of many ailments, for instance: internally as—a stimulant and carminative; externally as—an antipruritic, counterirritant and antiseptic by the ancient Egyptians, Chinese, Indians, Greeks and Romans. Earlier it was obtained by mere cooling of volatile oils from—ssasafras, rosemery, lavender, sage; while the Ancient Greeks and Romans derived it CH3 as a by product in the manufacture of wine. Nowadays, camphor is obtained on a large-scale synthetically (racemic mixture) from the a-pinene O present in the terpentine oil (Chapter 5). C(CH3)2 African natives used plant extracts in their ritual ceremonies whereby the subject would lose his/her complete body movements but shall remain mentally alert for 2 or 3 days. Later on, the earlier civilization also discovered a number of fermented drinks solely derived from carbohydrate—rich plant CAMPHOR substances invariably containing alcohols and vinegar. With the passage (A Bicyclic Ketone)  2 PHARMACOGNOSY AND PHARMACOBIOTECHNOLOGY of time they also recognised certain plant products exclusively used for poisoning their spears and arrows in killing their preys and enemies as well. Interestingly, they found that some plant extracts have the unique property of keeping the new meat fresh and also to mask its unpleasant taste and flavour. The human beings belonging to the ancient era in different parts of the globe independently discovered the inherent stimulating characteristics of a wide variety of drinks exclusively prepared from the vegetative source as stated below in Table 1.1. Table 1.1 Stimulating Characteristics from Vegetative Sources S. Common Name Biological origin Part Active Distribution No. (Family) used Ingredient 1. Guarana Paullinia cupana Seed Caffeine Brazil, Uruguay Kunth (2.5-5.0%) (Sapindaceae) Tannin (Catheochutannic acid) 25% 2. Paraguay Tea Ilex paraguariensis Leave Caffeine South America or Mate St. Hill. (upto 2%) (Aquifoliaceae) 3. Coffee Bean Coffee arabica Seed Caffeine Ethiopia, or Coffee Seed Linne’ or (1-2%) Indonasia, C. liberica Trigonelline Sri Lanka, Brazil (Rubiaceae) (0.25%); Tannin (3-5%) Glucose & Dextrin (15%); Fatty Oil (trioleoglycerol) and palmitoglycerol (10-13%) Protein (13%) 4. Coca Kola Coca nitida Seed Caffeine Sierra Leone, or Kolanuts (Ventenat) anhydrous Congo, Nigeria Schott et Endlicher (£ 1%) Sri Lanka, Ghana (Sterculiaceae) Brazil, Indonesia Jamaica 5. Tea or Thea Camellia sinensis Leave Caffeine China, Japan, Linne’s O. Kuntze or (1-4%) India, Indonesia (Theaceae) Leaf Gallotannic Sri Lanka bud acid (15%) Volatile oil (Yellow) 0.75% 6. Cacao Beans Theobrome cacao Seed Fixed Oil Ecuador, Columbia or Cacaoseeds Linne’ (35-50%) Malasia, Curacao, (Sterculiaceae) Starch (15%) Mexico, Trinidad Protein (15%) Brazil, Nigeria Theobromine Camerrons, Ghana (1-5%); Caffeine Philippines, (0.07-0.36%) Sri Lanka Figure 1 shows the basic nucleus of ‘Xanthine’ and ‘Purine’; besides the three well-known members of the Xanthine family viz., Caffeine, Theophylline and Theobromine.  INTRODUCTION 3 O O R3 H H N N N HN N R1N N N N O N N O N H R2 Xanthine Purine Caffeine: Theophylline: Theobromine: R1=R2=R3=CH3; R1=R2=CH3; R3=H; R2=R3=CH3; R1=H; Fig. 1.1 The Xanthine and Purine Structures Figure 1.2, illustrates the mode of synthesis of caffiene essentially from the same precursors present in Caffea arabica as the three purine alkaloids (see Fig 1.1) found in order biological sys- tems which have been studied so far at length, either from a compound which may afford an active 1-carbon fragment (e.g., serine, methanol, glycine and formalin) or from formic acid. D E O CH3 A = Active 1-carbon fragment [serine, methanol, glycine H3 C C N7 A and formalin]; N1 6 B = a-Amino acetic acid (H2N.CH2COOH) or glycine 5 C 8 C = Amide nitrogen of Glutamine CH 2 4C [HOOC.CH2.CH2CH.NH2.COOH]; C2 3 B N9 D = Carbon dioxide; O N E = Nitrogen from Aspartic acid A CH3 [HOOC–CH2CH(NH2).COOH]. C CAFFEINE Fig. 1.2 Mode of Synthesis of Caffeine z Methionine along with the said four compounds act as active precursors of the three ‘Methyl Groups’ at N1, N3 and N7 positions respectively. z Glycine is responsible for the contribution of C-4, C-5 and C-7, z Carbon dioxide contributes C-6, z N-1 is provided from aspartate, and z N-3 and N-9 are derived from the amide nitrogen of glutamate. Such elaborated and intensive studies of chemical constituents present in ‘Natural Products’ could only be feasible with the advent of various advancement in the field of ‘Phytochemistry’. However, it is pertinent to mention here that the scientific reasonings for the various age-old established characteristic medicinal properties have been adequately ascertained and determined in the past two centuries. A critical survey of literatures would reveal that a few chemical entities were not only identified but also known to the therapeutic armamentarium between the said era. A few typical examples are enumerated below in a chronological order, as stated in Table 1.2.  4 PHARMACOGNOSY AND PHARMACOBIOTECHNOLOGY Table 1.2 Examples of Plant Constituents in Use from 1627 to 1830 S. No. Period Researcher Chemical Entity Remarks 1. 1627-1691 R. Boyle Alkaloid(s) (probably) Present in Opium 2. 1645-1715 N. Lemery Alcohol As a solvent in (French Apothecary) extraction processes 3. 1709-1780 A.S. Marggraf Sugar isolated from many (German Apothecary) plant sources including Sugar-Beet 4. 1742-1786 K.W. Scheele Organic acids isolated from natural oxalic, malic, citric, sources. gallic, tartaric and prussic (HCN) 5. 1805 Serturner Meconic acid Present in Opium (German Chemist) 6. 1811 Gomeriz Cinchonine Isolated from (Portugese Chemist) Cinchona Barks 7. 1817 Serturner Morphine An alkaloid present (Geman Chemist) in Opium 8. 1817 Pelletier and Strychnine An alkaloid from Caventou Strychnos Nux (French Chemist) Vomica 9. 1819 - do - Brucine - do - 10. 1820 Meissner Veratramine An alkamine from Green Hellebore. 11. 1830 – Amygdalin A cyanophore glycoside from Bitter Almond. Considerable progress has been made in the nineteenth century when chemists seriously took up the challenge of synthesizing a plethora of organic compounds based or ‘biologically-active- prototypes’. Some of these purely ‘synthesized compounds’ essentially possessed structures of ever increasing complexity; and later on, after systematic pharmacological and microbiological evaluations proved to be yielding excellent useful therapeutic results. Evidently, as most of these ‘tailor-made’ compounds having marked and pronounced therapeutic indices were found to be existing beyond the realm of ‘pharmacognosy’ or more specifically ‘phytochemistry’—an altogether new discipline under the banner of ‘medicinal chemistry’ came into existence. However, this particular discipline almost remained dormant since the era of Parcelsus. But now, the ‘medicinal chemistry’ has acclaimed deserving wide recognition across the globe due to its own legitimate merit and advantages. In short, three major basic disciplines became largely prevalent with regard to the development of drugs, namely: z Pharmacognosy: embracing relevant information(s) with regard to medicines exclusively derived from natural sources, for instance: plants, animals and microorganisms, z Medicinal Chemistry: covering entirely the specific knowledge not only confined to the science of ‘synthetic drugs’ but also the basic fundamentals of ‘drug-design’, and z Pharmacology: dealing particularly the actions of ‘drugs’ and their respective effects on the cardiovascular system and the CNS-activities.  INTRODUCTION 5 Over the years, with the tremendous growth of scientific knowledge and valuable informations the three aforesaid disciplines have fully-emerged as ‘complete sciences’ within their own spheres. Though copious volumes of ancient literatures in Chinese, Egyptian, Greek, Unani and Indian (Ayurvedic) systems of herbal medicines were found to contain factual and invariably exaggerated claims of their therapeutic efficacies, yet when they are evaluated intensively on a scientific basis with the advent of latest analytical techniques, such as: FT-IR, NMR, MS, GLS, HPLC, HPTLC, X-Ray Diffraction, ORD, CD and UV-spectroscopy—it has adequately and promptly provided an elaborated structure of various complex chemical constituents. A few select typical examples of known compounds are given in Table 1.3. 1.2 IMPORTANCE OF NATURAL DRUG SUBSTANCES In general, natural drug substances offer four vital and appreciable roles in the modern system of medicine thereby adequately justifying their legitimate presence in the prevailing therapeutic arsenal, namely: (i) Serve as extremely useful natural drugs. (ii) Provide basic compounds affording less toxic and more effective drug molecules. (iii) Exploration of biologically active prototypes towards newer and better synthetic drugs. (iv) Modification of inactive natural products by suitable biological/chemical means into potent drugs. The aforesaid aspects shall be briefly dealt with in the sections that follows: 1.2.1 Serve as Extremely Useful Natural Drugs On a recent survey conducted by the World Health Organisation (WHO) globally, around 20,000 medicinal plants are being used profusely either in pharmceutical industry or in folk medicines. Interestingly, about 1.4% do possess well-established, widely—proven and broadly accepted un- equivocally active constituents. De Souza et al.* in 1982 opined on a serious note that—“the usual success rate of discovering new drugs from natural sources is solely based not only on the conception but also on the implemen- tation of ingenious comprehensive strategies which invariably explore and exploit the untrapped potential of the natural sources”. In fact, there are four ways by which the above objectives may be accomplished reasonably and legitimately, such as: (a) Isolation of novel genotypes from marine and terrestrial ecosystems, (b) Genetic engineering: creating novel and altered genotypes, (c) Biochemical manipulation of selected pathways, and (d) Supersensitive and specific selection techniques and evaluation for varied bioactivities. * De Souza, NJ et al., Annu. Rep. Med. Chem, 17, 301, 1982.  Table 1.3 Examples of Chemical Constituents Present in Herbal Plants 6 S.No. Common name(s) Biological origin (Family) Chemical constituents Distribution Uses 1. Artemisinin or Artemisia annuna Linne, CH3 China Treatment of H Qinghaosu Linne, (Asteraceae) cerebral malaria; Active against O both chloroquine O sensitive and H3 C O chloroquine- PHARMACOGNOSY AND PHARMACOBIOTECHNOLOGY H resistant strains H of Plasmodium H O falciparum CH3 O ARTEMISININ 2. Doxorubicin or Streptomyces O OH — Treatment of CH2 Adriamycin and coeruleorubidus breast cancer, Daunorubicin or Streptomyces various types of Cerubidine peucetius var CH2 R carcinomas, acute caesius OH Leukemia; Daunorubicin Treats acute Lymphocytic H3 C O O H HO O Leukmias. H3 C O H H H NH 2 HO DOXORUBICIN : R = OH; DAUNORUBICIN : R = H; 3. Ginkgo Ginkgo biloba O Eastern Asia Ginkgolides A, Linne O Southeastern B, C, and M inhibit (Ginkgoaceae) O United States. platelet-activating O factor (PAF); HO OH H3 C reduces capillary CH3 fragility and blood loss from the O CH3 capillary vessels that may ultimately O CH3 check ischemic O brain damage. GINKGOLIDE–A (Contd.)  CH2 OH HO O 4. Ginseng Panax quinaquefolius American ginseng Known to possess Linne and (p.q.) in Eastern tonic stimulant HO OH O Panax ginseng C.A. Mey H3 C United States and diuretic and (Araliaceae) Canada; carminative OH Asian gingseng (P.g.) properties; CH3 In Eastern Asia reported to act presently cultivated significantly on profusely in Korea, metabolism, CNS CH3 CH3 Japan and the former 7 endocrines; Soviet Union. Exhibits adaptogenic (antistress) activity. CH3 OH HO OH H H3 C CH3 O O OH INTRODUCTION CH2 OH GINSENGOSIDE Rg1 5. Gum opium or Papaver somniferum Turkish Anatolian Strongly narcotic opium or Linne or H N—CH3 plain extends to and hypnotic; Poppy Seed or Papaver album Northern border of Centrally acting Maw Seed Deendolle Laos; India; China, analgesic. (Papaveraceae) Democratic peoples republic of Korea. HO O OH MORPHINE 6. Rauwolfia Rauwolfia serpentina India, Myanmar, Treatment control sepentina Linne Bentham Sri Lanka; Vietnam; of hypertension; (Apocynaceae) N Malaysia; Indonesia; As an antipsychotic N The Phillippines. agent. H3 CO H H H OCH3 O H OCH3 H3 COOC OCH3 OCH3 RESERPINE 7 (Contd.) 7. Taxol or Taxol brevifolia Northwestern Treatment of 8 AcO O Pacitaxel or Nutt United States. metastatic Pacific Yew (Taxaceae) H3 C CH3 OH carcinoma of O O the ovary after CH3 failure of first O CH3 N line or followup O OH chemotherapy; H HO AcO Treatment of breast O cancer after failure PHARMACOGNOSY AND PHARMACOBIOTECHNOLOGY of combination O chemotherapy for TAXOL metastatic disease. 8. Curare or Strychnos castenaei Orinpoco basin; As a disgnostic South American Weddell; Upper Amazon aid in myasthenia Arrow Poison S. toxifera Bentham; regions; gravis; S. crevauxii CH3 Eastern Ecuadorian As an adjunct H O OH OCH3 G. Planchon + plateau. to electroshock (Logniaceae); and N treatment in Chondendron neuropsychiatry tomentosum 2Cl to control convulsion Ruiz et Pavon H H caused due to tetanus 3H2 O (Menispermaceae) and strychnine + N poisoning. OCH3 HO CH3 CH3 O TUBOCURARINE CHLORIDE 9. Yohimbine Pausinystalia West Africa. Treatment of yohimbe (K. Schum) impotance in Pierre N patients with (Rubiaceae) N vascular or diabetic H H problems. H H H3 COOC OH YOHIMBINE (Contd.) 10. Cantharanthus Cantharanthus CATHARANTHINE Madagascar, Treatment of or roseus G. Don OH India, South lymphocytic PORTION Vinca (Apocynaceae) N America, Austria, lymphoma, CH2 CH3 Formerly South Africa, advanced testicular designated as Europe, The carcinoma, Vinca rosea West Indies, histocytic Linne’ Southern lymphoma, N It has a close United States. myosis COOCH3 H2 SO4 resemblance to H fungoids, Vinca minor VINDOLINE PORTION Hodgkin’s disease, Linne’, commonly Kaposi’s sarcoma N known as choriocarcinoma Periwinkle. and breast cancer CH2 CH3 Unresponsive to H O other diagnosis. H3 CO N OCCH3 H Vincristine sulphate R COCH3 HO (R = CHO); O INTRODUCTION Vinblastine sulphate (R = CH3) 9  10 PHARMACOGNOSY AND PHARMACOBIOTECHNOLOGY A few typical examples of drugs derived from natural sources and their respective uses are given in Table 1.4. Table 1.4 Examples of Drugs from Natural Products S.No. Name Biological Origin(s) Isolation Synthesis Uses 1. Atropine Atropa beladona 1831 1883 Spastic colitis, gastro (Linne) enteritis, peptic ulcer; antispasmodic. 2. Ergotamine Claviceps purpurea 1918 1961 To prevent or abort (Fries) vascular headaches, (Migraine and cluster headache) 3. Morphine Papaver somniferum 1805 1956 As narcotic analgesics (Linne) strongly hypnotic. 4. Prostaglandins C-20 Lipid 1962 1969 PGE1-certain (PGE1 & PGE2) Metabolites in vitro congenital heart defects from essential as a gastric antisecretory unsaturated fatty acids and gastroprotective of food (Linoleic acid) agent; PGE2-for termination of second trimester pregnancies. 5. Physostigmine Physostigma 1864 1935 In ophthalmology to venesonum (Balfour) treat glaucoma; decreases intraocular pressure. 6. Quinine Cinchona succirubra 1820 1944 For treatment of malarial (Pavon et Kloyzsch) fever. 7. Scopolamine Atropa belladona, 1881 1956 As CNS-depressant; (Hyscyamine) Datura stramonium, in motion sickness; Hyoscyamus nigher; in preanaesthetic (or Egyptian henbane) sedation; in obstetric Scopolamine amnesia along with other (Hyscyamine) analgesic to calm delirium. 1.2.2 Provide Basic Compounds Affording Less Toxic and More Effective Drug Molecules The numerous examples of naturally occurring plant products that serve as prototypes for other medicinally potent compounds either having closely related structures prepared exclusively by semisynthetic routes or possessing relatively simpler (less complex) purely synthetic structural analogues have been adequately described in various literatures. A few interesting examples of such compounds shall be described in this context as under: 1.2.3 Exploration of Biological–Active–Prototypes towards Newer and Better Synthetic Drugs A plethora of better synthetic drug models gained considerable recognition in the therapeutic arsenal that were solely derived on the biologically-active-prototypes. It is, however, pertinent to mention here that these synthetic models not only possessed similar and better therapeutic index but also  INTRODUCTION 11 S. No. Natural Semisynthetic Synthetic 1. Morphine Hydromorphone Methadone (Narcotic Analgesic) CH3 N CH3 HO HO CH3 C C CH2 CH3 O O H O H NCH3 NCH3 Propoxyphene O HO CH3 N CH3 CH3 C C CH2 CH3 O CH2 Ibuprofen 2. Salicin and Acetyl salicylic acid Ibuprofen salicyclic acid (Asprin) (Analgesic) CH2 OH CH3 O OH H 2 C OH H C COOH O OH HO COOH H3 C C O CH2 COOH O HO H3 C CH CH3 3. Ephedrine Phenylpropanolamine Tetrahydrozoline (Adrenomimetic) OH CH3 H OH CH3 H C C N N C C N H H CH3 H H H N Salicin and salicylic acid (Analgesic) Acetyl salicyclic acid (Asprin) H Ephedrine (Adrenomimetic) (Contd.)  12 PHARMACOGNOSY AND PHARMACOBIOTECHNOLOGY 4. Atropine Homatropine Glycopyrrolate (Anticholinergic) C H3 C O OH H3 C N + H3 N N H3 C O C C Br O OH CH2 OH O O C C O C C H H Note: The dotted areas in the above chemical structures show the presence of essential characteristic features in the natural (biological-active-prototype), semisynthetic and synthetic models. exhibited fewer side effects than their corresponding naturally occurring constituents. A few typical examples are enumerated below: (a) Procaine from Cocaine—As Local Anaesthetic: Procaine Cocaine 3 3 2 3 2 3 2 (b) trans-Diethylstillbestrol from—Estradiol—as Estrogenic Hormone: trans-Diethylstilibersterol a-Estradiol 3 OH 2 2 3 HO (c) Chloroquine from Quinine—as Antimalarial: Chloroquine CH CH2CH3 CH2 H N CH2CH3 Quinine CH2 H H H C CH3 C H CH2 CH2 NH CH2 HO C N H3CO H N Cl N  INTRODUCTION 13 1.2.4 Modificaton of Inactive Natural Products by Suitable Biological/ Chemical Means into Potent Drugs This particular role of natural products is not only distinctly different from the rest, as discussed in section 1.2.1 through section 1.2.3, but also has its prime importance by virtue of the fact that certain constituents present in them do not exhibit any significant biological activity or chemical means surprisingly give rise to quite effective and potent drugs that are not easily obtainable by other known methods. The following examples will expatiate the above facts squarely: Examples: 1. Vitamin* A from—carotene (isolation from carrots i.e., Dacus carota) H 3C CH3 CH3 H 3C CH3 CH3 CH3 CH3 CH3 β-Carotene H3C CH3 CH3 CH3 OH b-Carotene CH3 Vitamin A (Retinol) Vitamin A (Retinol) 2. Taxol by conversation of 10–Dasacetylbaccatin III (Isolated from the needles of Taxus baccata): Synthetic Route 10–Dasacetylbaccatin III Taxol (see Table 1.3) Taxol is an antineoplastic agent invariably used in breast cancer. 3. Progesterone and Pregnenolone by conversion of Diosgenin (aglycone of Saponin Dioscin from Dioscorea tokoro Makino): H CH3 CH3 O CH3 C O CH3 CH3 O CH3 CH3 H H H Synthetic HO O Route Diosgenin Progesterone b-Carotene which acts as a precursor of the former. * 2 Moles of RETINOL are produced from 1 mole of d-b  14 PHARMACOGNOSY AND PHARMACOBIOTECHNOLOGY CH3 C O CH3 CH3 HO Pregnenolone Pregnenolone 4. Hydrocortisone and Corticosterone from Stigmasteol (occurs abundantly as Phytosterol Mixture from Soyabeans and Calabar Beans) CH2OH H 3C CH3 C O CH3 HO CH 3 OH CH3 C2H 5 CH3 CH3 Chemical HO O Biological Route Hydrocortisone Stigmasterol Stigmasterol CH2OH C O HO CH3 CH3 O Corticosterone In addition to the Third World nations, the technologically advanced countries like the United States have experienced a phenomenal change towards the acceptance of herbal medicines over the expanded OTC usages of such drugs. It is believed that in the Twenty First Century a quantum leap forward would be distinctly seen in the world pharmaceutical market. A few such projection of pharmaceutical products by the year 2001 may be glanced as detailed below: S. No. Name of Product(s) Uses Estimated Sales (USD)*/Year 1. Plantago Seed or Cathartic, 300 Million Psyllium Seed or Purgative Plantain Seed 2. Scopolamine and Nicotine Motion sickness, Patches Calming delirium, As Scopolamine and Nicotine anticholinergic agent 1 Billion 3. Taxol Patches Antineoplastic agent 1 Billion 4. Vinblastine and Vincristine -do- 100 Billion * USD: United State Dollar.  INTRODUCTION 15 It may appear to be quite realistic and amazing that in the near future about 50% of the healthy- market-share would be captured legitimately by drugs belonging to the natural origin. It is not out of place to assert that on one hand science is advancing in a tremendous logarithmic progression towards gene-synthesis, rocket-fuels, super computers, electronic cash-transaction across the globe, fax machine, paperless offices, modern analytical computer-aided instruments, auto analysers for routine industrial analysis for on-going chemical and biological processes and final products metioulously designed and skillfully formulated life-saving drugs; while on the other hand the confidence of the people being restored at a steady pace towards the ancient herbal drugs right from the treatment of constipation to management and control of malignancies in human beings. Of course, the so-called ‘Crude-Drugs’ are presently available in well refined and latest state-of- the-art packings as over the counter (OTC) drugs through chemists and druggists and super markets across the world. Perhaps that day is not too far when a common person will be tempted to grow medicinal plant in the kitchen garden rather than growing spring onions, lettuce, cucumber and french beans for their daily needs. It is a pity that the inhabitants of the modern society is virtually over-loaded by the usage of tonnes of chemicals used in the form of medicines for the cure of various ailments. 1.3 NATURAL DRUGS SUBSTANCES: CULTIVATION AND PRODUCTION It is pertinent to mention here that the actual production of ‘natural drug substances’ invariably adopts a number of different routes and methods based on the fact that their diversified origin as present in plant, microbial and animal kingdom. These three sources shall be discussed individually in the sections that follow: 1.3.1 Plant Products Many countries in the world have a ‘God-gifted’ natural reserve of medicinal plants. Because of their judicious and cautious administration by the expertise of indigenous-systems of medicine people could survive and thus explore and conquer the world as per the historical evidence. In the past, lack of knowledge, non-availability of adequate storage facilities and proper scientific means and methods of cultivation and collection a good number of useful medicinal plants almost reached a point of not only depletion but also extinction. With the advent of scientific knowledge abundantly available these medicinal plants are now grown in an organised fashion whereby proper identification, right cultivation, due harvesting in the correct time of the year to yield maximum desired chemical constituents, and adequate prevention from spoilage and infestation due to improper storage. Nowadays, plant-extracts are available commercially across the globe so that these may be incorporated duly in several tried and tested herbal preparations. Various advanced ‘analytical methods’ help a long-way in establishing the true picture of their quality, for instance: percentage of Eugenol present in Clove oil determines its quality; percentage of Cineol in Eucalyptus oil shows its purity; percentage of Total Alkaloids in Datura stramonium depicts its medicinal value. A few countries in the world are noted for their supply of certain specialized plant extracts, namely:  16 PHARMACOGNOSY AND PHARMACOBIOTECHNOLOGY India : Opium extracts; China : Extract of Artemisia annuna; United States : Ginkgbo biloba extracts (GBE) Korea, Japan : Panax ginseng extracts; Madagascar : Catharnthus roseus extracts; Eastern Europe : Ergot produced by mechanical inoculation of rye plants with spores of a selected fungus. 1.3.2 Cell-Culture Techniques It essentially involves the production of the ‘desired secondary constituents’ that caters for a viable alternative means of drug-plant-cultivation. Extensive studies have revealed that under the influence of ‘stress-conditions’, for instance: reacting with a suitable pathogen-may ultimately help in simulating the yield of some specific highly desired constituents in plant-cell suspension cultures. However, the actual slow growth of the cell-biomass possess a serious obstacle in the wide acceptance of this innovated technique. Perhaps the day is not too far when the plant genes which are responsible for coding enzymes catalyzing the desired biosynthetic routes may be converted to rather more swiftly growing bacterial or fungal cells. 1.3.3 Microbial Metabolites A number of ‘microbial metabolites’ produced by well-defined process of fermentation give rise to certain very useful therapeutically potent drugs, especially the antibiotics and related antieoplastic agents as exemplified below: (a) As Antibiotics: for instance: (i) Chloromycetin – from Streptomyces venezualae Bartz, (ii) Erythromycin – from Streptomyces erythreus (Walksman) Walksan & Henrici, (iii) Gentamycin – from Micromonospora purpurea MJ Weinstein et al. (iv) Penicillin O – from Penicillium chrysogenum, (v) Streptomycin – from Streptomyces griseus (Krainsky) Walksman et Henrici, (vi) Tetracycline – from Streptomyces viridifaciens. (b) As Antineoplastic Agents: for examples: (i) Dactinomycin – from several Streptomyces spp. (ii) Daunorubicin – from Strepomyces peucetius G. Cassinelli; P. orezzi. (iii) Mitomycin C – from Streptomyces caespitosus (griseovinaceseus) (iv) Pilcamycin (or Mithramycin) – from Streptomyces argillaceus n. sp. and S. tanashiensis Figure 1.3, illustrates the outline of the fermentation process usually accomplished in a pharmaceutical industry whereby dried drugs are produced in a large scale. However, in certain specific instances, per se cephalosporins, the end product obtained by the fermentation process is routed through semisynthetic means to yield the desired pharmaceutical substance.  INTRODUCTION 17 Sterilized-Number Medium (50 – 100 KL) Fermentation Propogation of Desired Organism in Aerated Tanks After Certain Duration Fermented Broth Separation Cell Growth Culture Broth