Acetone and methanol fruit extracts of Terminalia paniculata inhibit HIV-1 infection in vitro

Abstract

In this study, we report the in vitro anti-HIV1 activity of acetone and methanol extracts of fruit of Terminalia paniculata. Cytotoxicity tests were conducted on TZM-bl cells and peripheral blood mononuclear cells (PBMC), the CC₅₀ values of both the extracts were ≥260 μg/mL. Using TZM-bl cells, the extracts were tested for their ability to inhibit replication of two primary isolates HIV-1 (X4, Subtype D) and HIV-1 (R5, Subtype C). The activity against HIV-1 primary isolate (R5, Subtype C) was confirmed using activated PBMC and by quantification of HIV-1 p24 antigen. Both the extracts showed anti-HIV1 activity in a dose-dependent manner. The EC₅₀ values of the acetone and methanol extracts of T. paniculata were ≤10.3 μg/mL. The enzymatic assays were performed to determine the mechanism of action which indicated that the anti-HIV1 activity might be due to inhibition of reverse transcriptase (≥77.7% inhibition) and protease (≥69.9% inhibition) enzymes.

Keywords:

• Terminalia paniculata
• anti-HIV1 activity
• acetone extract
• methanol extract
• protease
• reverse transcriptase