Lesson 2

• Crude drugs

  – are plants or animals, or their parts w/c after collection are subjected only to drying or making them into

  transverse or longitudinal slices or peeling them in some cases

  – vegetable or animal drugs that consist of natural substances that have undergone only the process of collection and drying
• I. Extractive - mixture of substances/substance extracted

  II. Marc - undissolved portion of a drug that remains after the extraction

  III. Menstruum - solvent
• Indigenous Plants - plants that grow in their native countries.
• Naturalized Plants - plants that grow in a foreign land or in a locality

  other than their native homes.
• Crude drugs - natural product and has not been improved by shredding, grinding, chipping, distilling, evaporating, extracting, artificial mixing.
• Crude - vegetable or animal drugs that consists of natural substances that have undergone only the processes of collection
• Cultivated Medicinal Plants - have been propagated for centuries in China, India Europe and many other lands
• Commercial Origin of Drugs – refers to the production and its channels of trade
• Collection

  • getting samples to determine the quality

  • ensuring the true natural source of the drug

  • improper collection might result to complete or partial substitution.
• Harvesting

  • Varies with each drug produced and with the pharmaceutic requirements of each drug
• Drying

  • prevents microbial contamination

  • inhibits enzyme and other chemical reactions

  • facilitates milling

  • convenience

  • by the sun (natural) or by artificial heat

  • Regulation of airflow
• Tray dryers- drugs w/ no volatile oils, need deactivation of enzymes
• Vacuum dryers - drugs sensitive to higher temperature ex. Tannic acid & digitalis leaves
• Spray dryers - drugs w/c are highly sensitive to atmospheric conditions
• Curing

  • special method of drying

  • involves other processes such as sweating or fermentation to bring about changes in the constituent
• 2 modes of harvesting:

  Hand labor

  Mechanical
• Garbling

  • final step in the preparation of crude drug.

  • Removal of extraneous matter
• Animal Drugs

  – Are produced from wild or domesticated animals.

  – Wild animals must be hunted (whale, musk deer) or fished for (cod and halibut).

  – If insects: mostly from wild insects
• Evaluation of Drugs

  • done to maintain QUALITY and CLASSIFY the drugs according to its active constituent.
• Organoleptic Evaluation

  • “impression on the organs” – appearance, odor, taste, sound or snap of its fracture and feelings
• Microscopic Evaluation

  • essential to the study of adulterants (e.g insects, animal feces, mold, fungi etc.) in powedered plant and animal drugs
• Lignin: stains red w/ a drop of phloroglucinol and conc. HCL
• mucilage: pink with rhuthenium red
• starch & hemicellulose: blue with N/50 iodine solution
• Biological/Bioassays

  • Assays on animals and living organism indicates the strength of a drug

  • To determine pharmacological activity, potency and toxicity
• 3 Methods of Bioassay:

  Toxic- uses animals

  Symptomatic- animals

  Organ- uses isolated organ or tissues
• Chemical Evaluation

  • Active constituents of many natural drugs have been determined by chemical methods (assays) to determine the official potency
• Chemical methods

  isolation, purification and identification of active constituents
• Qualitative chemical tests

  Identification Test (I.T) of alkaloids, glycosides and tannins
• Quantitative Chemical Tests

  acid value (resins, balsams), ester value (balsams, volatile oils), acetyl value (volatile oils), etc.
• Chemical Assays

  for alkaloid, resin, volatile oil, glycosides, vitamins etc.
• Instrumental Analysis

  analyse the chemical groups of phytoconstituents using chromatographic and spectroscopy
• Physical Evaluation

  • Application is rare but extensively applied to the active principles of drugs such as alkaloids, volatile oils, fixed oils and others
• Alphabetical

  • simplest way

  • arranged in alphabetical order of their Latin and English names, (common names), vernacular names
• Morphological

  • Plants are grouped according to structure.
• Organized drugs - obtained from direct plant parts
• Unorganized drugs - prepared from plants by some intermediate physical processes such as incision, drying or extraction with a solvent and not containing any cellular plant tissues
• Taxonomical

  • Large number of plant families have certain distinguishing characteristics that permit drugs from these families to be studied at one time
• Pharmacological

  • Therapeutic use of drugs
• Chemical

  • Therapeutic of drugs are based on chemical constituents and is the preferred method of study

  • Most drugs contain a variety of constituents, some therapeutically active, others chemically active and still others antagonistic to each other