ER 2020 Pharmacognosy: CHAPTER 1. Definition, history, present status and scope of Pharmacognosy 2 Hours

CHAPTER 1. Definition, history, present status and scope of Pharmacognosy 2Hrs MEANING or DEFINITION OF PHARMACOGNOSY >Pharmacognosy, known initially as materia medica, defined as the study of crude drugs obtained from plants, animals and mineral kingdom and their constituents. >There is 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. >They derive the word pharmacognosy from two Latin words Pharmakon, ‘a drug,’ and Gignoso, ‘to gain a knowledge of ’. It means ‘knowledge or science of drugs’. History of Pharmacognosy →We can regard > History of Pharmacognosy as a history of Pharmacy and medicine because pharmacognosy had its origin in health-related activities of the most primitive human race of the remote past. → In the early period, primitive men went in search of food and ate at random, plants or their parts like leaves, fruits, etc. → As they observed no harmful effects, they considered them as edible materials and used them as food. → Observing other effects, they started using them as medicine or as defence instruments, e.g. poisonous and death arrow poison. Trial and error got this knowledge. → It is probable that by a combination of these various methods, ancient people could build up a considerable knowledge of medicinal and food plants. → They transmitted gained knowledge from generation to generation and new information to it. → A group of people in each generation started specialising in collecting and processing medicinal plants and using them against various diseases. →Before people could read and write, they passed the knowledge of drugs from one generation to another either orally or by the use of some signs and symbols. → As far as historical records are available, the Chinese pharmacy stems from Shen Nung (2700 B.C) who investigated the medicinal value of several hundred herbs and had Pen T-sao recording 365 drugs. The most important clinical manual of Traditional Chinese Zhang Han lun (Treatise on the treatment of acute diseases caused by cold). → From the Sung Dynasty (960-1276) the establishment of the pharmaceutical system has been a Standard practice throughout the country. → In 1552, during the later Ming Dynasty, Li Shi Zhen (1548-1593) began work on the monumental Pen Ts'ao, Kan Kan Mu (Herbal with commentary). This listed 1892 drugs, 376 described for the first time with 1160 drawings. → Ancient Egypt witnessed the most complete medical documents Ebers Papyrus, a collection of 800 prescriptions, mentioning 700 drugs and Edwin Smith Papyrus, containing surgical instructions and formulas for cosmetics. → Kahun Medical Papyrus is the oldest document - comes from 1900 BC and deals with the health of women, including birth and instructions. → Many of the present day important drugs like Henbane, Opium pomegranate, castor oil, aloe, onion and many others were in common use in Egypt about 4500 years ago. →They described the earliest plant medicines used in the Ayurvedic system around 1200 BC with a list of 127 plants. → They divided the Ayurvedic writing into three main scripts-Charaka Samhita, Sushruta Samhita, Astanga Hridaya Samhita. →The practice of medicine using medicinal plants flourished most during Greek civilisation when many historical personalities practised herbal medicines. →Some of the early naturalists, scientists and physicians who contributed enormously to the development of human knowledge about medicinal plants, including Hippocrates (460-370 BC) Aristotle (384-322 BC) Theophrastus (370-287 BC) Dioscorides Pling and Galen (131-200 AD) →They regarded →Hippocrates as the father of medicine for his contribution to human anatomy and physiology. Also known to have collected and identified several medicinal plants. And practised herbal medicine. →His materia medica comprises some 300 to 400 medicinal plants. → Aristotle recorded the properties of over 500 plants of medicinal importance. →Dioscorides published five volumes of the book, entitled ' De Materia Medica' in 78 AD. This described over 600 medicinal plants. →Galen, for the first time in history, described hundreds of recipes and formulations of medicinal preparations containing both plant and animal ingredients. →The present day Galenical pharmacy is a manifestation of his methods and recipes. →Present day allopathic and homoeopathic systems of medicine on the doctrines expatiate by Galen. →In earlier days, the apothecary (Pharmacist -physician) used to handle the works of both the pharmacist and physicians. PRESENT STATUS OF PHARMACOGNOSY: In times of yore, pharmacognosy was considered as the study of drugs of natural origin. The 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, extraction, isolation and purification of herbal drugs and modern plant biotechnology production and utilisation of drugs; trade and utilisation of medicinal and aromatic plants and their contribution to the 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 phytochemicals. emphasises the biodiversity of plants and encompasses biosynthesis, extraction, isolation of compounds with TLC identification, bioactivity determination 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. Such enormous information about the natural drug gives rise to a subject that is now recognized as modern pharmacognosy. Pharmacognosy 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 pharmacognostical aspects of natural drugs.