Extraction Technologies For Medicinal And Aromatic Plants - Unido

6 AQUEOUS ALCOHOLIC EXTRACTION OF MEDICINAL AND AROMATIC PLANTS BY FERMENTATION
6.5 Application of Asava Arishta Technology in
New Drug Discovery
The Ayurvedic dictum with regard to asava arishtas that “older
is better” needs to be scientifi cally evaluated. The process of preparing
asava arishtas appears to involve:
1. Slow hydro-alcoholic extraction at room temperature of
crude plant material particles fl oating in the liquid. Since the particle size of
the plant material fl oating in the liquid is small, the effectiveness of extraction
may be higher because of the larger surface area.
2. During the process, if the product is kept for a prolonged
period, the probability of development of analogues of some of the pure
chemical compounds of the plant material is high.
With a view to enhance the success rate of isolation of pure
“druggable” compounds from medicinal plants, it is advised to start from
2- to 3-year-old self-fermented preparations than from solvent extracts. The
chances of successful isolation of effective therapeutic compounds using
this approach may be high and need to be evaluated.
6.6 Conclusions
Fermentation was applied hundreds of years ago in Ayurveda
to develop asava arishtas, a multiherbal product, with a view to increase the
shelf life and also to enhance the effi cacy profi le. The race for discovery of
new molecules is getting increasingly competitive; at the same time, lack of
new and novel pharmacophores is a big impediment which slows down drug
discovery. Nature continues to be a source of pharmacophores, although the
compounds isolated may not be “druggable” as such. They need to be derived,
mostly to enhance their potency. In asava arishtas, the self-fermented
products can undergo continuous chemical transformation which goes on
beyond hydro-alcoholic extraction of the suspended material. This may result
in novel natural molecules with enhanced therapeutic activity.
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