Evaluation of Shilajit as Putative HIV-Protease Inhibitor

Ethanol and aqueous extracts of Shilajit were included for the present in vitro study. Pepsin was used as a substitute for HIV-protease to evaluate inhibitory activity of Shilajit extracts, as pepsin has close resemblance with HIV-protease in proteolytic activity. Both the extracts;viz.,ethanol and aqueous,showed potent inhibitory activity with IC50 values of 9.61 and 193.80 µg/ml respectively. In our earlier study, these extracts exerted their anti-HIV activity via multiple mechanisms of action; viz., interference with the gp120 / CD4 interaction and inhibition of HIV-reverse transcriptase. In the present study, they showed potent inhibitory activity against pepsin enzyme, suggesting that Shilajit may be useful as a HIV protease inhibitor. The inhibitory activity could be due the high flavonoids content.