PHARMACOGNOSY

• Pharmacognosy


  The study of drugs from natural sources including plants, animals, microorganisms, and inorganic sources
• Pharmacognosy term first coined by J.A. Schmidt


  1811
• Pharmacognosy introduced by C.A. Seydler in his work Analecta Pharmacognostica


  1815
• Pharmacognosy

  • Covers all information on medicines from natural sources
  • An applied science that deals with biologic, biochemical and economic features of natural drugs and their constituents
  • Embraces knowledge of history, cultivation, selection, distribution, collection, and preparation
• History of use of drugs

  • Insulin (animal source)
  • Digoxin (plant source)
  • Penicillin (microorganism)
  • Morphine (plant source)
  • Urokinase (animal source)
  • Sambong (plant source)
  • Colchicine (plant source)
  • Erythromycin (microorganism)
  • Bacitracin (microorganism)
  • Conjugated estrogen (animal source)
• Digoxin vs Digitoxin


  Digoxin has a shorter half-life and better protein binding compared to Digitoxin
• Digoxin and Digitoxin are both narrow therapeutic drugs
• Persons involved in Pharmacognosy

  • Hippocrates
  • Aristotle
  • Paracelsus
  • Pedanius Discorides
  • Christian Aenotheus Seydler
  • Cladius Galen
  • Johann Adam Schmidt
  • Theophrastus
• Active constituents


  • Responsible for therapeutic effect
  • Can be pure/single chemical substances or mixtures of principles
• Active constituents


  • Lavender oil (mixture of principles)
  • Senna (single entity - anthraquinone glycoside)
  • Coconut oil (mixture of principles)
  • Psyllium (mixture of principles - gums and mucilage)
  • Morphine (single entity)
• Inert constituents


  • No definite pharmacologic activity
  • Examples in plants: cellulose, lignin, suberin, cutin, starch, albumin, coloring agents
  • Examples in animals: keratin, chitin, muscle fiber, connective tissue, collagen, glycogen
• Secondary plant substances


  • Constituents that are extracted, crystallized and purified for therapeutic use
  • 3 principal factors that influence them: heredity, ontogeny, environment
• Extraction


  • Removes substances that can be dissolved by the menstruum or solvent
  • Marc is the undissolved portion, percolate/extractive is the product
• Geographic source and habitat

  • Indigenous - plants growing in their native countries
  • Naturalized - plants grown in a foreign land or locality other than their native countries
• Ethnobotany

  The study of plants by humans
• Ethnomedicine


  The use of plants by humans as medicine
• Traditional medicine


  The sum total of all non-mainstream medical practices, usually excluding "western" medicine
• Pharmacopeia


  A book containing directions for the identification of samples and the preparation of compound medicines, published by an authority, government, or pharmaceutical society
• Drug biosynthesis or biogenesis


  The study of biochemical pathways leading to the formation of secondary constituents used as drugs, derived from 4 macromolecules
• Extractives (derivatives)


  Deals with the principle constituents found in natural substances by methods like extraction, distillation, maceration, percolation, digestion, infusion, etc.
• Natural product


  A chemical compound or substance produced by a living organism found in nature that usually has a pharmacological or biological activity for use in pharmaceutical drug discovery and drug design
• Types of drugs derived from plants

  • Herbal drugs derived from specific parts of a medicinal plant
  • Compounds isolated from nature
  • Nutraceuticals or "functional foods"
• Value of natural products

  • Provide useful drugs difficult to produce synthetically
  • Supply basic compounds that can be modified to be more effective or less toxic
  • Serve as prototypes or models for synthetic drugs
  • Contain compounds that can be modified to produce potent drugs not easily obtained by other methods
• Taxonomy


  The science of naming organisms in their correct integration to existing system of nomenclature, including phylogeny (natural relationship among plants and animals)
• Crude drugs


  Vegetable or animal drugs that consist of natural substances that have undergone only the processes of collection and drying

  
• Preparation of crude drugs

  1. Collection - Select the species to cultivate

  2. Harvesting - Gather the samples at a specific and proper period or season

  3. Drying - Removal of moisture; shelf-life of crude drugs rely on this step
• Phylogeny


  Natural relationship among plants and animals
• Genus


  • A group of species, in this case poppies, which are closely related
• L.


  Indicates the botanist who provided the first scientific description of the species and who assigned the botanical name
• Family


  A group of genera sharing certain traits (ex. Papaveraceae)
• Preparation of Crude Drugs

  1. Collection: Select the species to cultivate

  2. Harvesting: Gathering the samples at a specific and proper period or season

  3. Drying: Removal of moisture

  4. Curing: Special or modified drying process that uses Nitrats to enhance the properties of the plant's active ingredients

  5. Garbling: Final step in the preparation of crude drugs. It consists of the removal of extraneous matter, such as dirt

  6. Packaging, Storage and Preservation: Depend on the final disposition of crude drug ; for protection & marketability
• Packaging material for crude drugs


  • Goat skin
  • Kerosene tins
  • Well-closed container
  • Pressed and baled
• Ways to Classify Crude Drugs

  • Organoleptic
  • Chemical
  • Microscopic
  • Physical

  
• Evaluation of Crude Drugs

  • Organoleptic
  • Biologic Assay

  
• Types of Biological Assay Methods

  • Toxic
  • Symptomatic
  • Tissue methods
• Test Animals used in Biological Assays

  • Mice
  • Turtles
  • Rabbits
  • Rats
  • Cat
  • Chicken
  • Pigeon
• Phenol coefficient


  Used to assess the anti-infective activity of local anti-infectives that are being newly discovered; ratio of dilution of phenol to elicit the same activity as with the drug
• Chemical Tests for Crude Drugs

  • Anthraquinone Glycosides: Borntrager's test
  • Saponin Glycosides: Froth test, Capillary tube test, Hemolysis test
  • Cardiac Glycosides: Liebermann-burchard test, Kedde test, Keller-killiani test
  • Cyanophore Glycoside: Guignard test
  • Fixed Oils: Halphen's test, Baudouin test, Serger's test, Millon's test
  • Ergot: Van urk's reagent
  • Tropane: Vitali's test
  • Purine bases: Murexide test
  • Gums: Lead acetate
• Molecular Pharmacognosy


  A science dealing with the study of classification, identification, cultivation and protection of crude drugs and production of effective elements at molecular level
• Analytical Pharmacognosy


  Detection of purity of crude drugs