Author: Dr. Raja Naika H, Assistant Professor, Department of Environmental Science, Tumkur University.
Medicinal plants are the sources of important therapeutic aid for alleviating human ailments. With increasing realization of the health hazards and toxicity associated with the indiscriminate use of synthetic drugs and antibiotics the interest in the use of plants and plant-based drugs has revived throughout the world. Nature has always been a first-rate drug store house, with its enormous range of plants that are known to have effective therapeutic qualities. The medicinal plants have played a significant role in the most convenient and effective health care because these are not only natural, easily available, cost effective, safe and regenerative, but also the inherited knowledge of tribes and traditional medicine as a result of their long term association with the forests for time immemorial. In spite of tremendous advances made in the modern medicine, there are still a large number of ailments for which suitable drugs are yet to be found. There is an urgent need to develop safer drugs for the treatment of hepatitis, arthritis, diabetes, psoriasis, herpes, leucoderma, leukemia, AIDS etc. The Vedic literature also mentioned the identity and utility of herbs/herbal products in treating human ailments. Scrutiny of medical indications by the source of compounds has demonstrated that natural products and related drugs are used to treat 87% of all categorized human diseases, including antibacterial, antipyretic, hepatoprotective, anticancer, anticoagulant, anti-inflammatory, antiparasitic, wound healing and immunosuppressant agents, among others.
The World Health Organization (WHO) estimated that about 80% of the population in developing countries depends on traditional medicines, mostly plant drugs for their primary health care needs. All India Ethnobiological Survey carried out by the Ministry of Environment and Forests revealed that about 7,500 plant species belonging to 386 families and 2200 genera are used by 4,635 ethnic communities for human and veterinary health care across the country. India is one of the major supplies of medicinal plants with an annual turnover of herbal products worth Rs.23 billion USD of this, the domestic market of medicinal plants is about Rs.3 billion USD, which includes condiments and food additives (14%) herbal extracts (22%), essential oils, gums and resins (19%) and crude drugs (45%).
The growing interest in commercialization of plant-based medicines has lead to over-exploitation of the plants. Most of the pharmaceutical industries are highly dependent on the wild populations for the supply of raw materials for the extraction of medicinally important compounds. Hence, India has banned the export of several wild species in the form of raw materials, although the export of finished products containing the material is allowed. Despite this, about 95% medicinal plants collected in India are gathered from the wild, which includes trees (33%), herbs (32%), shrubs (20%), climbers (12%) and others constitute 3%. These collections are mostly destructive (72%) which include the entire plant (16.3%), reproductive parts like flowers, fruits and seeds (22.1%) or tuber, root and stem (39.5%). Such destructive and non sustainable collection methods coupled with low regeneration and habitat destruction have posed serious threat to the survival and availability of various medicinal plants in the wild.
If the process of destruction progresses in the same manner, the medicinal plants will be extinct soon. In this connection this article focuses mainly on Micropropagation of medicinal plants by advanced Biotechnological methods of culturing plant cells and tissues should provide a new means of conserving and rapidly propagating valuable, rare, and endangered medicinal plants. Due to lack of proper cultivation practices, destruction of plant habitats, and the illegal and indiscriminate collection of plants from their habitats, many of the species are severely threatened. Biotechnology plays a major role in the mass multiplication, germplasm conservation, secondary metabolite production and sustainable use of medicinal plants. The application of tissue culture for large-scale plant production meant for commercial purposes is well demonstrated in vitro multiplication of several medicinal plants. Some of these photographs show the Mass cultivation of Medicinal plants.