A natural product is a chemical compound or substance produced by a living organism – found in nature. Natural sources of drug are –plant, animal, mineral, microorganisms. Plant sources are leaf, bark, fruit, seeds. Drugs obtained from animal sources are heparin, insulin, thyroxin, cod liver oil, antitoxic cera. Microorganism sources are bacterial, fungi, molds etc. mineral sources are ferrous sulfate, magnesium sulfate, sodium bi carbonate, aluminum hydroxide. Animal sources are In the broadest sense, natural products include any substance produced by life. the field of organic chemistry, the definition of natural products is usually restricted to mean purified organic compounds isolated from natural sources that are produced by the pathways of primary or secondary metabolism. Many secondary metabolites are cytotoxic and have been selected and optimized through evolution for use as "chemical warfare" agents against prey, predators, and competing organisms. synthetic analogs of natural products with improved potency and safety can be prepared and therefore natural products are often used as starting points for drug discovery. Natural products have served as a major source of drugs for centuries, and about half of the pharmaceuticals in use today are derived from natural products. Interest in natural products research is strong and can be attributed to several factors, including unmet therapeutic needs, the remarkable diversity of both chemical structures and biological activities of naturally occurring secondary metabolites. About 40% of the drugs used are derived from natural sources. Plants provide a fertile source of natural products many of which are clinically important medicinal agents. Different strategies will result in a herbal medicine or in an isolated active compound. Drug discovery scientists often refer to these ideas as "leads," and chemicals that have desirable properties in lab tests are called lead compounds. Pharmaceutical chemists seek ideas for new drugs not only in plants, but in any part of nature where they may find valuable clues.
India is the biggest supplier of licit demand for opium required primarily for medicinal purposes. Besides this, India is located close to the major poppy growing areas of the world, with "Golden Crescent" on the Northwest and "Golden Triangle" on the North-East. The processes of industrialization, urbanization and migration have led to loosening of the traditional methods of social control rendering an individual vulnerable to the stresses and strains of modern life. The introduction of synthetic drugs and intravenous drug use leading to HIV/AIDS has added a new dimension to the problem, especially in the Northeast states of the country.
Ayurveda and charka samhita, have contributed towards this boom in Drug discovery.
Further information:
Handbook on drugs from natural sources describes the detailed information on subject. The major contents of this book are- An Introduction to Drugs From Natural Products, Plant Products Produced In Cell Culture, Target Site Delivery of Herbicidal Compounds, Recent Work on Some Thai Medicinal Plants, Immunoregulatory Compounds Derived from Hormones, Biologically-active Compounds from British Marine Algae , Development of Drugs from Cannabinoids, Bot. : Acacia Arabica Hindi : Babul, Sanskrit : Babbula, Bot. : Achyranthesaspera Linn. Eng : Prickly chaff flower, Bot : CuscutareflexaRoxbi, M : Aakaashvalli, H : Akasvel, Bot : GmelinaarboreaRoxb. M: Shiwan, H: Gamer, Bot: Meliaazedarach Linn. Eng.: Persian Lilac, Bead tree, Bot: Viola odorant, Hindi: Banaphasha, Sanskrit: Banaphasha etc.
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