Objective: To evaluate the in vitro anti-HIV-1 activities and mechanism of extracts from 6 traditional Tibetan medicines:Corydalis conspersa

Fallopia aubertii

Anemone vitifolia

Clematis urophylla

Saxifraga melanocentra and C. hexapetala. Method: Cell counting kit(CCK-8) cell cytotoxicity test and HIV-1 single cycle infection experiments were used to detect the in vitro anti-HIV-1 effect and cytotoxicity of extracts. The surface plasma resonance(SPR) technology

protease

integrase and reverse transcriptase inhibition assay were used to identify the potential targets of these extracts. Result: The extracts from F. aubertii

A. vitifolia and S. melanocentra showed dose-dependent anti-HIV-1 effect with little cytotoxicity. Their half maximal inhibitory concentrations (IC50) were (6.47±0.78)

(11.97±1.09)

(11.7±0.79) mg·L-1

respectively. All the above three extracts inhibited integrase activity. Conclusion: F. aubertii

A. vitifolia and S. melanocentra extracts potently inhibited HIV-1 virus in vitro

possibly through down-regulating integrase activity.