Evaluation of vegetable and animal drugs
1- Introduction about herbal and animal drugs and their preparations:
Crud drugs are vegetable or animal drugs that consist of natural substances that have undergone only the processes of collection and drying.
1- Plant origin: leaves, flowers, seeds and barks. Or vegetable saps, extracts and secretions.
2- Animal origin: whole animals, glands or organs, extracts and secretions.
I- When drugs consist of insects, the drugs are either:
II- When drugs consist of animals:
Vegetable drugs are arranged for study as:
1- Alphabetic: The drugs are arranged in alphabetical order.
2- Taxonomic: The drugs are arranged according to the plant source. Phyla, families, genera, species, variety (botanical classification).
3- Morphological: The drugs are divided into:
Leaves, flowers, fruits, seeds, herbs and entire organisms, woods, barks, rhizomes and roots.
Dried lattices, gums, resins, oils, fats and waxes.
4- Pharmacologic or therapeutic: Grouping of drugs according to the pharmacological action or therapeutic use.
5- Chemical: the drugs are divided into groups according to their most important constituent:
1- Carbohydrate: e.g., starch, agar, pectin.
2- Glycosides: vanillin, barbaloin.
a- Fixed oils and fats are glyceryl esters of fatty acids that are saponified by alkali: olive oil, peanut oil, sesame oil, caster oil.
b- Waxes are esters of fatty acids with high molecular weight monohydric alcohol e.g., bees wax.
4-Volatile oils (essential oils) e.g., peppermint oil, clove oil, cinnamon oil, anise oil, rose oil that responsible of odor of plants.
5- Steroids: are derivatives of cyclopentanophenanthrene e.g., estrogens, androgens, cholesterol, ergosterol.
6- Alkaloids: they are nitrogenous, crystalline or oily compounds. Usually basic in nature e.g., atropine, morphine, quinine, cocaine and reserpine.
7- Peptide hormones: these are active principles secreted by certain endocrine glands e.g., glucagons, insulin and oxytocin.
8- Enzymes: organic catalysts that are produced by living organisms e.g., pepsin, pancreatin, rennin.
9- Vitamins: chemical compounds that are necessary for normal growth and function of animals e.g., thiamine, riboflavin, ascorbic acid, vitamin E.
10- Antibiotics: chemical compounds produced biosynthetically that cause kill or inhibit microorganisms e.g., penicillin, tetracycline, erythromycin…..
A- Antigens or antibody preparations are capable of developing a state of immunity in the patient e.g., hepatitis B vaccine, IG, diphtheria antitoxin.
B- Biologics related to human food e.g., human albumin, anti-heamophilic factor.
12- Allergens substances that causes unusual responses called hypersensitivity in individuals, e.g., pollen grains, mold, spores, feathers, animal dander.
13- Poisonous plants: some higher plants and fungi produce toxic effects when introduced into the human body e.g., nightshade, water hemlock, amanita.
Pharmacopoeias: They are books recognized by the governments as the legal authority for standard of drugs. The united states pharmacopoeia is revised and reprinted every five years.
Official drug: is one that listed and described as definite therapeutic agent in pharmacopoeia.
Unofficial drug: is one that have not recognized in pharmacopoeia. They are listed in unofficial books e.g., British pharmaceutical codex.
The descriptive material pertaining to any of the drugs in the pharmacopoeia is known as the monograph.
In the monograph of a crude drug, the following information are generally covered:
1- Endogenous plant:
Plant is growing in native country, e.g., Hyoscyamus in Egypt, Cannabis sativa in India.
2- Naturalized plant:
Plants are cultivated in foreign land or in locality other than their native countries, e.g., cotton is naturalized in Egypt and endogenous to America.
3- Exotic plant:
Plant is used in countries where neither cultivated nor growing wild, e.g., tea, digitalis.
4- Marine drug:
It is a pharmacological active compound of marine origin, e.g., agar, carageenan, code liver oil.
5- Crude drug:
Drugs of animal or vegetable origin undergo processes of collection and drying only.
6- Commercial origin:
It is refers to its production and its channels trade, e.g., Alexandrian senna is the product growing in Khartom but it was shipped by way of Alexandria.
To evaluate a crude drug:
Can be established by actual collection of the drug from plants or animals origin → +ve identified.
How to determine the origin of the samples:
1- "Drug gardens' established by institutions engaged in pharmacognostical research.
2- Comparing unknown sample with a- a published description drug or b- with authentic drug samples.
2- quantity and purity
It is refers to the intrinsic value of the drug, i.e., the amount of medicinal principle or active constituents present.
How obtain high grade of quality?
I- Collection of the drug from the correct natural source at the proper time and in proper manner.
II- Preparation of the collected drug by proper cleaning, drying and garbling.
III- Proper preservation of the cleaned, dried, pure drugs against contamination with dirt, moisture, fungi, filth and insects.
Occurrence on the market (commercial forms):
B- Galinical preparation:
a- Extract خلاصه
The evaluation of a drug involves a number of methods:
1- Organoleptic evaluation:
Definition: The entire description of official crude drug monographs.
= Organs of sense = Macroscopic appearance of drug.
1- Shape and size (for entire drugs not powdered).
2- Odor and taste.
3- Color and external markings.
4- Fracture and internal color.
2- Microscopic evaluation:
Dealing with microscopic appearance of the herb in sectional view and in powdered form.
Microscopical evaluation is useful in the study of:
1- Histologic elements of herbs.
2- Detection of adulterant.
3- Quantitative microanalysis of admixed or adulterated powders.
1-Microscopical linear measurement
Used only in Root Rhizomes Bark
If closely related species are leaves: We need to
2- Ratio value:
1- Palisade ratio.
2- Stomata index.
3- Vein islet number.
4- Vein islet terminate number
It is the study of active constituents by the application of chemical and physical methods to small quantities (a few milligrams) of the drug in powdered form or to histologic sections of the drug. It offers a means by which constituents of many drugs may be isolated and purified.
It includes steps:
I- Isolation of A.C.:
A- By chemical solvents:
B- By micro-sublimation
II- Identification of constituents:
1- By crystallography
2- By melting point determination
3- By confirmative test
1- Chemical test.
2- Physical test
3- Biological evaluation
4- chemical evaluation
5- physical evaluation