Modern Drug discovery has very much advanced with many new techniques to ease the process. With the evolve of computational chemistry, it became easier to simulate structures of drug target proteins and their binding affinities with small molecules and thus helping to design new library of molecules. X-ray crystallographic studies are yielding the structures of target proteins and their active sites. Sequencing the genetic codes of micro-organisms such as viruses, giving the information about microorganism’s DNA/RNAs and related proteins. Based on these techniques, process of target validation, new molecules library design, their synthesis in thousands of numbers and finally are screened for their inhibitory activity against target protein through in-vitro and in-vivo methods. Among thousands of screened molecules, few may hit as lead compounds for animal study. Then phase clinical trials, ADME, FDA approval and finally commercialisation.
Now, if we trace back the history of drug discovery process, when there were no such modern techniques, majority of new drugs discovered were the bio-active molecules isolated from crude plant extracts, algae, fungi etc. whom scientists either discovered through serendipity or by thorough screening of crude plant extracts, which were given to patients in traditional medicine system. Until Quinine alkaloid was discovered as bio-active molecule present in Cinchona bark extract, this extract only was given as medicine for treating Malaria. The extracts of Taxus brevifolia plant were believed having anti-cancer activity, until people discovered the bio-active molecule Taxol was main content of this extract, which has potential to arrest mitotic cell division in tumor cells. The anti-inflammatory drug Aspirin was once isolated from Spiraea ulmaria herb. Penicillin, the first antibiotic drug, which ruled the world for decades, was first extracted from a Fungi.
Historically, every country, culture and civilisation in some or other way had practised traditional therapeutic system by using crude extracts of many plants and their parts by trial and error base over generations. Let it be European traditional medicine, Chinese herbal treatments, Persi-Arabic Unani medicinal practice, homeopathy Or our Ayurveda, all these systems were dependent on herbal resources.
Agreed that Ayurvedic medicinal practices does not fit into modern drug discovery processes, as this method lacks data to establish drug-target interaction and many more, but at the same time one cannot ignore that those herbal medicines made from crude extracts of many medicinal plants do have the biological activities. We never know, there may be treasure of bio-active molecules present in those medicines/extracts. Therefore, a thorough investigation of those extracts/medicines to dig out what bio-active molecule is present in them, which is responsible for pharmacological property. Some countable number of natural product chemists such as Prof. Sukhadev, have worked in this line. Still more and more efforts should be made to do research on these Indian traditional medicines to discover many hidden novel molecules that in future may be cure for many diseases.
