Inhibition of human immunodeficiency virus reverse transcriptase by Chinese medicines in vitro.

Thirty-five Chinese medicines, including extracts of traditional medicines or clinically useful recipes, herbs and isolated compounds, were tested for inhibitory activity against human immunodeficiency virus reverse transcriptase in vitro. Fourteen of the 35 medicines were found to be active. Baicalin, in particular, was studied in great depth. We found it to be a noncompetitive inhibitor of HIV RT, with an effective concentration (IC50) of 22 mumol/L. Chinese medicines were shown to be a rich source of potentially useful materials for the treatment of human immunodeficiency virus infection.