In India traditional medicines are govern by the D&C act of 1940 and the D&C rules of 1945. In 1959, the govt. of India recognizes the traditional Indian systems of medicine and amended the D&C act to include the drugs derived from traditional Indian medicines.
The products of traditional system can not be manufactured without a license from state drug control authorities and they should contains ingredients which are mentioned in the recognized books as specified in the D&C act.
In 1993, an expert committee appointed by the Indian govt. developed guidelines for the safety and efficacy of the herbal medicines to be incorporated in D&C act and rules. Herbal medicines have been used for thousands of years. The practices continue today because of its biomedical benefits and place in cultured beliefs in many parts of world.
The WHO has recognized the contribution and value of the herbal medicines used by large segment of the world's population.
A growing interest in usage has created the need for greater precision in preparation and evaluation, and has stimulated research into herbal medicines, various usage & application.
The western pacific region has a rich tradition of preparation & use of herbal medicines. In 1992, the WHO regional office for the western pacific invited a group of experts to develop evaluating herbal medicines.
These guidelines are publishing to support the application of evaluation principles by modern science to a tradition of herbal medicine that is still extremely vibrant and of growing interest through out the world.
The WHO is fully aware of the importance of herbal medicines to the health of many people throughout the world.
The World Health Assembly in resolution WHA 31.33(1978), WHA 40.33(1987), & WHA 42.43(1989) - has emphasized the need to ensure the quality of medicinal plant products by using modern control techniques and applying suitable standards.
The goal of WHO guidelines is-
• To strengthen research in the evaluation of the safety and efficacy of herbal medicines and
• To strengthen and promote the rational use of herbal medicines.
The objective of WHO guidelines is-
• To ensure the safety and efficacy of herbal medicines used in the health care systems of countries with in the region and else where in the world.
• To provide research criteria for evaluating the safety and efficacy of herbal medicines to propose a basics for the member states to develop their own research guidelines for the study of herbal medicines.
• To facilitate the exchange of research experience and other information so that a body of reliable data for the validation of herbal medicines can be accumulated.
Standardization includes study of morphology & microscopy of the drug to find out its natural identity with reference and also with certain specific chemical tests.
Need of standardization:
• Popularity of herbal medicines.
• To control microbial contamination & chemical constituents.
• For industrial requirements.
• For consumer point of view.
• For global potency of drug.
• To prevent batch to batch variation.
• To ensure authenticity, purity & safety.
Evaluation is done to find out the presence of adulterants and assay to find out quality of active chemical constituents.
Before carrying out standardization or evaluation sampling should be done this is necessary because there is lack of homogeneity.
Procedure for bulk sampling is -
Check for uniformity, physical stability (physical damage-container, moisture etc.)
If batch contains 5 containers, take sample from each one.
If batch contains 6-50 units, take sample from 5 units.
If batch contains 50 units, round up the no. of units to the multiple of 10 i.e.
E.g.: 51 unitsâ†'60 units (round fig.)â†'sample from 6 packages.
After opening inspect contents of the units are subjected for organoleptic character, presence of raw material (raw, powder, compressed etc.), presence of admixtures, foreign matters (sand, glass particles, and dirt etc.), mould or signs of decay, Presence of insects, presence of packaging materials originating from poor or degraded containers.
From each container take 3 original samples, takes samples from top, middle & bottom of containers, in case of sacks take samples by hand, 1ST from a depth of not less than 10cm from the top and 2nd & 3rd middle and bottom after cutting into the side of the packages. Seeds should be withdrawn with a grain probe.
In case of retail package sampling from each box & cartons etc. take at random 2 consumer packages from small batches (1-5 boxes), take 10 consumer packages. Prepare the pooled sample by mixing the contents of the selected consumer packages and proceed as final sample.
The general method of standardization includes:-
(1) BOTANICAL EVALUATION
(i) Sensory evaluation
a. Visual evaluation- colour (seen in day light & compared with reference), size (length, width, & thickness), shape.
b. Touch- fracture & texture characteristics, under 6x to 10x magnification, expressed as hard or soft and textures as fibrous, smooth, rough & glandular.
c. Odour- necessary to powder before examine, compared with reference, expressed as aromatic, fruity, musty, mouldy & rancid.
d. Taste- done only for the drugs mentioned in monographs.
(ii) Foreign matters
Should be free from visible signs of contamination by moulds or insects, and other animals etc. any soil, stones, sand, dust and other foreign matter must be removed before subjecting to cut or ground for testing.
The crude drug is sampled in following amount-
- roots, rhizomes and barks - 500 gms
- leaf, flowers, seeds and fruits- 250 gms
- powdered material - 50 gms
Sample drug is spread on white paper, if drug is powdered one, then it is 1st passed through sieve 250. Then foreign matters are identified and picked up, separated foreign matters are then weighed & expressed as % content of the total sampled tested. Then compared with the% amt. of foreign matters allowed for the given drug in monograph.
Foreign matter is a material consisting of-
- Parts of medicinal plant other than those named with the limits specified for the plant material concerned.
- Any organism, part or product of an organism, other than that named in the specification and description of the plant material concerned.
- Mineral admixtures not adhering to the medicinal plant materials, such as soil, stones sand and dust etc.
a. Histological study- study of T.S. of crude drug or characteristics of the powdered drug under microscope. Therefore T.S. of the drug is prepared by cutting the drug in small & thin sections. Drugs like bark, roots, rhizomes etc. are very hard, are previously soaked in water or equal parts of water, ethanol & glycerin overnight to make soft to easy the cutting of T.S. The T.S. are then treated with one of the following to clarify from unwanted substances-
1. Chloral hydrate- T.S. + chloral hydrate, Î"â†' dissolves aleurone grains, starch grains and expands the collapsed & delicate tissues without causing any under swelling of the drug, having refractive index 1.44-1.48 and helps to dissolve CaO crystals clearly.
2. Lacto chloral- used where chloral hydrate is not suitable, used in cold.
3. Lacto phenol- used for lower plants like fungus, lower organisms like mite, nematodes or for pollen grains (hot & cold conditions).
4. Sod. Hypochlorite- use for leaching purpose of deeply colored tissue. E.g.
Xylene R + Light pet. Etherâ†' Use to clear off fats & oils.
The cleaned T.S. are then stained with HCl + Fluroglucinol & observed under microscope.
b. Histochemical studies-
1. Cellulose Cell Wall- T.S. + 1-2 drops iodinated ZnCl2+ wait for 1 min. + 1 drop I2+ 1 drop H2SO4 â†' Blue stain.
2. Lignified Cell Wall- T.S. + Fluroglucinol + keep for 2 min. + 1 drop HCl â†' Pink to Red cherry colour.
3. Cuticullar Cell Wall- T.S. + 1-2 drops Sudan red + wait for few min. + Î" gentlyâ†' Orange red/ Red staining.
4. Aleurone Grains- T.S. + 1 drop I2 in Ethanol â†' Yellow - Brown.
To the above + Ethanolic Trinitrophenol â†' Yellow colour.
To the above + 1ml HgNO3 â†' Brick Red colour.
5. CaCO3 - T.S. + Acetic acid /HCl â†' CaCO3 dissolves slowly with effervescence.
6. Ca-Oxalate- T.S. + Acetic acid â†' Insoluble.
T.S. + HCl â†' Soluble with out effervescence.
7. Fats, Fatty Acids & Resins- T.S. + 1-2 drops Sudan red + stand for few min.â†' Orange Red to Red.
To above + Ethanol + Î" â†' Resins dissolves, Fats & Fatty Acids remains intact.
8. Hydroxy Anthraquinone- T.S. + 1 drop KOH â†' Red stain â†' Cell contains 1, 8-dihydroxy Anthraquinone.
9. Insulin- T.S. + 1-Napthol + H2SO4 â†' Spherical aggregation of crystals of insulin turns to Brownish Red & dissolve.
10. Mucilage- T.S. + Ruthenium Red â†' Mucilage shows up as transparent spherical diluted fragment.
Dry sample + Thionine + stand for 15 min. + wash with Ethanol â†' Mucilage forms Violet Red colour.
11. Starch- T.S. + I2 solution â†' Blue or Reddish Blue colour.
T.S. + small vol. Of Glycerol + Ethanol + observe under polarize light â†' White rings are seen (Helpful in seeing hylum).
12. Tannin- T.S. + 1 drop of FeCl3 â†' Bluish Black or Greenish Black colour.
About Author / Additional Info: