Pharmacognosy - Chapter 1 PDF

# UNIT-1 ## Definition, history, present status and scope of pharmacognosy ### Points to be covered in this topic * DEFINITION OF PHARMACOGNOSY * CLASSIFICATION OF PHARMACOGNOSY FIELD * HISTORY OF PHARMACOGNOSY * PRESENT STATUS AND SCOPE OF PHARMACOGNOSY ## 1.1 DEFINITION OF PHARMACOGNOSY In th...

# UNIT-1 ## Definition, history, present status and scope of pharmacognosy ### Points to be covered in this topic * DEFINITION OF PHARMACOGNOSY * CLASSIFICATION OF PHARMACOGNOSY FIELD * HISTORY OF PHARMACOGNOSY * PRESENT STATUS AND SCOPE OF PHARMACOGNOSY ## 1.1 DEFINITION OF PHARMACOGNOSY In the beginning, man used products derived from numerous plants and animals as food. Due to the fact that diseases were created by man, these compounds were gradually used as pharmaceuticals to treat the illnesses. The utilization of plants as a source for medications has long historical roots. Pharmacognosy, may be defined as the study of crude drugs obtained from plants, animals and mineral kingdom and their constituents. The term Pharmacognosy was first introduced by C. A. Seydler, in 1815 in his doctoral thesis titled "Analecta Pharmacognostica". The word pharmacognosy is derived from two Greek words: Pharmakon and Gignosco. Pharmacognosy is mainly concerned with the drugs of biological origin. There are six basic origins of drugs: 1. **Animal sources:** Drugs obtained from animals are entire animals like thyroid organ or extracts like liver extracts, bees wax, certain hormones. 2. **Plant sources:** Drugs obtained from plant consist of entire plant or parts of plant and can be divide into organized or unorganized drugs. * Organized drugs are direct parts of plants. * Unorganized drugs, prepared from plants are not the direct parts of plants. 3. **Mineral:** The natural ores or minerals are collected by mining in open quarries, and the product is further purified for various pharmaceutical uses. 4. **Marine:** Marine natural products are important sources of biologically active agents, and various bioactive compounds have been extracted from marine organisms like tunicates, sponges, soft corals. 5. **Microorganism:** A large number of natural products from microbial sources are used as pharmaceutical excipients and others are used as important drugs or as nutritional supplements. 6. **Biotechnology:** Biotechnology is often used in pharmaceutical manufacturing. Notable examples include the use of bacteria to produce things such as insulin or human growth hormone. | SOURCE OF ORIGIN | IMAGE | EXAMPLE | |---|---|---| | Plant source | | Senna leaf, Cinchona bark, Nux vomica seed, Rauwolfia root, Saffron, Clove bud etc. | | Animal source | | Wool, Silk, Honey, Shark liver oil, Cantharides and Insulin etc. | | Mineral | | Asbestos, Chalk, Kaolin, Bentonite etc. | | Marine | | Agar-agar, Holotoxin A, Manoalide, Ciguatoxin, Ara-C etc. | | Microorganism | | Bacillus subtilis (Bacitracin) Streptomyces venezuelae (Chloramphenicol) Streptomyces griseus (Streptomycin) | | Biotechnology | | Recombinant DNA technology - Human growth hormone, Humulin. | ## 1.2 CLASSIFICATION OF PHARMACOGNOSY FIELD Pharmacognosy may be divided into following fields: | FIELD OF PHARMACOGNOSY | DESCRIPTION | |---|---| | Medical ethnobotany | The study of the traditional use of plants for medicinal purposes. | | Phytotherapy | The study of medicinal use of plant extracts to treat disease. | | Ethnopharmacology | The study of the pharmacological qualities of traditional medicinal substance. | | Phytochemistry | The study of chemicals derived from plants (including the identification of new drug candidates derived from plant sources). | | Zoo pharmacognosy | The process by which animals self- medicate, by selecting and using plants, soil, and insects to treat and prevent disease. | | Marine pharmacognosy | The study of the chemicals derived from marine organisms. | ## 1.3 HISTORY OF PHARMACOGNOSY As long ago as human civilisation existed, there has been a history of herbal remedies. As mentioned in Papyrus Ebers, an old document written in 1600 B.C., The text of document is dominated by more than 800 formulae and 700 different drugs. Gradually, all the natural products, utilized by physicians were compiled together to form the 'Materia Medica' giving their detailed information. ### FOLLOWING ARE THE IMPORTANT CONTRIBUTOR IN THE HISTORY OF PHARMACOGNOSY:- * **Shen Nung:** The emperor Shen Nung written "Pen-t'sao", oldest known herbal (around 3000 B.C) which contains 365 drugs one for each day of the year. * **Charaka:** Charaka made 50 groups of 10 herbs each of which, He believed that would meet the requirements of a typical physician. * **Sushrutha:** Sushrutha arranged 760 herbs in 7 set based on their common properties. * The well-known treatises in Ayurveda are Charaka Samhita and Sushrutha Samhita. The Indian System of Medicine, or Ayurveda, is used by a significant section of the Indian people. * **Hippocrates:** The great Greek physician (460 - 360 B.C.) known as 'Father of Medicine', dealt with anatomy and physiology of human beings. * **Aristotle:** Aristotle, the renowned philosopher (384-322 B.C.), is well known for his studies on animal kingdom. * **Theophrastus:** Theophrastus (370 - 287 B.C.) is well known for his studies on plant kingdom. * **Dioscorides:** A Greek physician (40-80 A.D.) described several plants of medicinal importance in "De Materia Medica". He is known as Father of pharmacognosy. * **Seydler:** Coined the term "Pharmacognosy" in his work titled "Analecta Pharmacognostica". * **Galen:** The first pharmacist, Galen, was known to have had a number of pain-relieving materials, including opium in his apothecary.  * **Pliny the Eider:** It was Pliny the Eider, who compiled 37 volumes of natural history. * **Le'mery:** Le'mery (1645-1715) describe the importance of the extraction method and alcohol as an extractant. * **William Withering:** William Withering in 1785 gave a description of some of the medicinal qualities of digitalis leaves. * **Derosne:** In 1803, the French pharmacist, Derosne isolated narcotine from opium. * **Sertuerner:** In 1806, Sertuerner isolated morphine from opium. In the next few years, strychnine (1817), emetine (1817), brucine (1819), piperine (1819), quinine (1820) and colchicine (1820) were isolated. * **Pelletier:** The French Pharmacist, Pelletier first reported the isolation of strychnine. Strychnine was initially isolated from ignatius beans and then from nux vomica seeds. Other important discoveries during this period were the isolation of: * Nicotine from tobacco leaves - Posselt and Reimann (1828) * Cocaine-Neumann (1860) * Ouabain - Hardy and Gallows (1877) * Pilocarpine - Gerrard and Hardy (1875) * Ephedrine - Nagai (1887) * Podophyllotoxin - Kuersten (1891) **Swede Linnaeus:** Swede Linnaeus (1707-1778) introduced the system of naming the plants "binomial system" which is still followed. ### Scientist and their work in the development of pharmacognosy- | NAME | CONTRIBUTION | PERIOD | |---|---|---| | Dioscorides | De Materia Medica book is compilation of several plants. He is known as father of pharmacognosy | 40-80 A.D.* | | Gaius Plinius Secundus or Pliny the Elder | Encyclopedic work entitled Naturalis Historia | 25-70 A.D. | | Galen | Galenical Pharmacy | 131-200 A.D. | | Hippocrates | Studied human anatomy and Physiology | 460-360 B.C* | | Aristotle | Animal kingdom | 384-322 B.C. | | Theophrastus | Plant kingdom | 370-287 В.С. | | Carl Linnaeus | Binomial classification | 1753 | | CA Seydler | Coined word Pharmacognosy | 1815 | | Sir Joseph D. Hooker | Plant nomenclature | 1817-1911 | | George Bentham | Plant nomenclature | 1800-1884 | | Friedrich Sertürner | Isolated first alkaloid morphine from opium | 1806 | *\[A.D. (Anno Domini), B.C. (Before Christ)]* The progress achieved in botanical studies during 19th century had a direct influence on Pharmacognosy. * Plant classification was developed by- * Bentham and Hooker (1862-1863) * A.W. Eichler (1883) * Engler and Prandtl (1887-1898). * In 1865, G. Mendel's important observations on plant hybrids were published. * 'The Anatomical Atlas of Crude Drugs' was published by Berg in 1865. * 'An Anatomical Atlas of Powdered Vegetable Drugs' was compiled by Greenish and Collin in 1904. Pharmacognosy is an important bridge between the pharmaceutical and basic sciences. It is a vital link between Ayurvedic and Allopathic systems of medicines. It provides a system wherein the active principles of crude drugs derived from natural origin can could be dispensed, formulated and manufactured in dosage forms acceptable to allopathic system of medicine. ## 1.4 PRESENT STATUS AND SCOPE OF PHARMACOGNOSY Older medications that are being re-examined include liqcorice, valerian, veratrum, podophyllum, senna, digitalis, opium, colchicum, belladonna, etc. On the basis of folklore, medicinal plants utilized in herbal medicines are also explored. Many nations, including India, have developed herbal pharmacopoeias, which contain regulatory criteria for therapeutic plants, in response to the ongoing rise in demand for herbal products and in an effort to preserve the quality of those goods. There are now monographs for many different herbal medicines that include descriptions, testing for identity and purity, and assays of the active ingredients. The growth of various scientific disciplines has benefited greatly from pharmacognosy as an applied science. Since plants are the main focus of pharmacognosy, a pharmacognosist should have a foundational understanding of both botany and zoology. ### Scope of pharmacognosy * To provide information on drugs and healthcare products from natural sources. * To study large number of unexplored natural substances as drugs and diagnostics. * To provide knowledge about purified constituents from the crude drugs. * To examine natural drugs for quality, purity and activity. * Applications in food and spice industry as well as in forensic sciences. * Herbal medicines have become more popular in recent years because it is believed that these do not have any side or toxic effects as compared to the modern medicines. * The trend of pharmacognosy has also been changed from taxonomic and morphologic studies to biochemical, physiological and genetic investigations of the drug sources. * The pharmacognosy has played an important role in the transformation of various basic life subjects. * To establish knowledge of the vegetable drug under botany and animal drugs under zoology. * Pharmacognosy is vital link between pharmacology and medicinal chemistry because it enables isolation of purified natural drug, converts into medicine and evaluate its therapeutic effects. * Pharmacognosy links basic science, pharmaceuticals, ayurvedic and allopathic system of medicine too each other. * To manufacture various drug from botanical origin in pharmaceutical industry. * To helps as a research tool in the new drug/dosage form development. * To improve plant chemistry (phytochemistry) significantly with the.