Department of Dravyaguna
Dravyaguna is essentially compilation of ancient Indian medical knowledge. According to one estimate, 850 medicinal plants are used in Ayurveda, the Traditional Indian Medicine (TIM). If history of Ayurvedic system is explored, it can be seen that during the Vedic period, the mode of study was oral communication. Later on several texts (samhita) including Charaka Samhita, Sushruta samhita, Agnivesha samhita, Bhela samhita, Prashara samhita, and Kashyapa samhita were composed.
Later on, scholars in the medieval time felt the need to assemble the work on Ayurveda at one stage and several nighantu were composed. The roots of the word nighantu lie in nigama; which means a secretive thing. Nighantu are considered to be nucleus of Ayurvedic philosophy. Majority of the work was done between eight to fifteenth century A.D. Important nighantu are tabulated below:
1. Astangta of Vagbhata 8th
2. Paryaya ratnmala of Madhava 9th
3. Dhanvantri 10th
4. Arundutta of Arundutta 12th
5. Sodhala 12th
6. Madhava Dravyaguna 13th
7. Hrdaya deepika of Bopadev 13th
8. Madanpala 14th
9. Kaiadeva 15th
Vedic era is considered to be golden period for Ayurveda. Onset of Mogul and British Empire was major setback to Ayurveda. Although Ayurvedic practice was banned in India but during the British Empire, Indian medicinal plants were subjected to scientific investigations and several texts were composed. Materia Medica composed during the British Empire was based on ancient Indian medical knowledge but work on chemistry of the Indian medicinal plants was salient feature.
Nomenclature of medicinal plants in Ayurveda
Medicinal plants in Ayurveda have several Sanskrit names and synonyms ranging from two to many. The scholars classified medicinal plants mostly on basis of morphological and organoleptic characters. Ashwagandha, the name has been derived from smell of the plant resembling that of horse stool. Sarpagandha has been derived from serpentine shape of roots. Dughdpheni has been derived because of the milky latex present in the drug. Although classification mentioned in Ayurvedic texts is of little significance in toady’s scientific world but its importance cannot for ruled out. Some drugs used in Ayurveda are of controversial origin and the ancient knowledge can be of great help in naming the plants according to taxonomic standards. Even the phytochemicals derived from medicinal plants are named according to its biological source; examples are jatamansone and shankhpushpine.
Dravyaguna in modern age
Critical study of Dravyaguna is essential for exploring its full strength. Drugs derived from Indian medicinal plants, either single or polyherbal, have been subjected to animal (preclinical) testing and promising results have been published in indexed journals. Several coded formulations have been screened for large scale clinical trials. Dravyaguna has definite role to offer as far discovery of novel leads and hits are discovered. A fraction of plants described in Indian Materia Medica has been scientifically tested. Medicinal plant like Aswagandha, Brahami, Mandukparni, Kalmegha, Chiryata, Guggul, Kutki and Shatavari are integral part of Western Herbal Materia Medica. It is worthwhile to note that several Indian medicinal plants are part and parcel of American Herbal Pharmacopoeia (AHP) and British Herbal Compendium (BHC). Scenario for Dravyaguna is changing and it has become an interdisciplinary rather than conventional subject. Recently bioinformatics tools have been applied for integrating Indian medical knowledge at one platform. Dravyaguna has made significant contribution to the Herbal Materia Medica. The term ‘Herbal Materia Medica’ covers global medicinal plants and is not restricted to one or other traditional systems of medicine. Dravyaguna coupled with ‘Reverse Pharmacology’ can act as powerful tool for discovering cost-effective and potent medicines.