Pharmacognostical Approach towards Authentication and Quality Evaluation of Medicinal Plants-A Compendious Description

World Health Organization currently encourages, recommends and promotes traditional herbal medicines in National Healthcare Programmes as such drugs are easily available at low cost and inherently safer than the potent synthetic drugs. According to WHO, about 80% of the world population relies on traditional medicines, mostly on plant drugs. Adulteration, however, becomes a very serious problem with the crude drugs, and often occurs when a drug is not easily available or when its price is comparatively high. Adulteration, in many cases, may not be intentional and in many cases could occur due to mistaken identity of the plants. WHO acknowledged that pharmacognostical standards should be proposed as a protocol for the diagnosis of herbal drugs, and internationally-recognized guidelines for their quality assessment are necessary. The plant materials should be collected at an appropriate stage of their growth and thereafter well authenticated by detailed taxonomical study. The most convenient time of collection is the period during which the drug is highest in its contents of active principles. According to WHO guidelines, medicinal plant materials are categorized according to sensory, macroscopic and microscopic characteristics. An examination to determine these characteristics is the first step towards establishing the identity and degree of purity of such materials, and should be carried out before any further tests are undertaken.