MODULE 2

• Pharmacognosy


  Applied science that deals with the biological, biochemical and economic features of drugs or biological origin and their constituents
• Pharmacognosy deals with knowledge of drugs & pharmaceuticals
• Pharmacognosy is a science that deals with plants and animal constituents
• Flückiger (1828–94): '"the simultaneous application of various scientific disciplines with the object of acquiring knowledge of drugs from every point of view"'
• Pharmacognosy


  Term coined by Anotheus Seydler (aka C.A. Seydler) in 1815, from the Greek words "Pharmakon" meaning drug and "gignosco" meaning to acquire the knowledge of
• Babylonians made clay models of man and had medicinal practices using plants and animals
• Babylonians had the Law of Hammurabi (772 BC) which included medicinal practices
• Babylonians had medicinal plants of 250 species
• Babylonians had mages (practitioners of magic) and physicians
• Babylonians used wheat and barley
• Egyptians practiced embalming using resins, plant oil, and animal fats in 1550 BC
• Egyptians had the Papyrus Ebers which included medicinal plants and their uses, human anatomy, and the use of plants
• Egyptians had priest doctors
• Ayurveda, the traditional Indian medicine, dates back to 2500 BC
• Charaka and Sushruta were ancient Indian physicians
• Pedanios Dioscorides wrote De Materia Medica or the Medicinal Material in 78 AD
• Substances discovered in De Materia Medica

  • Aloe, belladonna, colchicum, ergot and opium
• Ergonovine was used to stop bleeding (abortion) and ergotamine was used for migraine
• Claudius Galen (131-200 AD) was the father of pharmaceutical compounding and created Galen's cerate, a cold cream for soothing irritated skin
• CA Seydler (1815) coined the term "pharmacognosy" in his book Analecta Pharmacognostica
• JA Sischidt (1811) wrote Lehrbuck de Materia Medica
• Fluckiger: 'Pharmacognosy is the "Simultaneous application of various scientific disciplines with the objective of acquiring drugs from every point of view" - biologic, biochemical, and economic'
• Pelletier and Caventou discovered quinine
• Friedrich Serturner discovered morphine
• Crude drugs


  Plant exudates that are collected and dried
• Natural substances


  No molecular modification has been made
• Derivatives or extractives


  Chief principles or constituents of crude drugs, obtained using a solvent/menstruum and leaving behind an undissolved portion called the marc
• Solvents/menstrua used to extract derivatives

  • Hexane for fats, alcohol for resins, acetone for chlorophyll, hot benzene for chrysarobin
• Indigenous plants


  Native to a country
• Naturalized plants


  Foreign to a land, like Rinorea niccolifera, a metal-eating plant indigenous to the Philippines but imported to other countries for soil pollution
• Geographic source & Habitat

  The region in which the plant or animal yielding the drug grows
• Infusion


  Extraction using hot water, with a short contact time of 3-5 minutes
• Maceration


  Soaking in a solvent for long periods, not necessarily hot
• Percolation


  Filtering of fluids through porous materials, like making simple syrup USP
• Digestion


  Extraction at low heat, below 35-40°C, not boiling
• Decoction


  Extraction using boiling water
• Distillation


  Purifying liquids by heating and cooling to separate volatile oils from plants, using evaporation and condensation
• Collection of crude drugs


  • Small scale collection, improper collection can result in partial or complete substitution, best time to collect: flowers at dawn, bark in spring/summer, root crops when upper ground portion is about to wither
• Marijuana


  • Young leaves contain cannabidiol, mature leaves contain cannabinol (THC), the psychoactive substance
• Harvesting of crude drugs

  • Large scale, using manual labor or mechanical devices like pickers, mowers, binders, swath, steel; manual labor used for potent constituents and if not heat sensitive