Evaluation of selected South African medicinal plants for inhibitory properties against human immunodeficiency virus type 1 reverse transcriptase and integrase
Journal of Ethnopharmacology
Department of Microbiology, Univ. of Venda for Sci. and Technol., PMB X5050, Thohoyandou 0950, South Africa; Center for Global Health, Department of Infectious Diseases, University of Virginia, P.O. Box 801379, Charlottesville, VA 22908-1379, United States; REGER, UMR-5097 CNRS, Univ. Victor Segalen, Bordeaux 2, 146 Rue Léo-Saignat, 33076 Bordeaux Cedex, France; Lab. de Chim. des Substances Veg., Ctr. de Rech. en Chim. Moléc., Université de Bordeaux 1, 351 Cours de la Libération, 33405 Talence, France; Inst. Europ. de Chimie et Biologie, 2 Rue Robert Escarpit, 33607 Pessac, France; Department of Botany, University of Pretoria, Pretoria 0001, South Africa; Instituto de Investigaciones, Facultad de Farmacia, Universidad de Los Andes, Venezuela
Seventeen aqueous and methanol extracts from nine South African medicinal plants, ethnobotanically selected, were screened for inhibitory properties against HIV-1 reverse transcriptase (RT). Isolated compounds were additionally evaluated on HIV-1 integrase (IN). The strongest inhibition against the RNA-dependent-DNA polymerase (RDDP) activity of RT was observed with the methanol extract of the stem-bark of Peltophorum africanum Sond. (Fabaceae) (IC50 3.5 μg/ml), while the methanol extract of the roots of Combretum molle R.Br. ex G. Don (Combretaceae) was the most inhibitory on the ribonuclease H (RNase H) activity (IC50 9.7 μg/ml). The known compounds bergenin and catechin, and a red coloured gallotannin composed of meta-depside chains of gallic and protocatechuic acids esterified to a 1-O-isobutyroly-β-d-glucopyranose core, were isolated from the methanol extract of the roots and stem-bark of Peltophorum africanum. The gallotannin inhibited the RDDP and RNase H functions of RT with IC50 values of 6.0 and 5.0 μM, respectively, and abolished the 3′-end processing activity of IN at 100 μM. Catechin showed no effect on RT but had a moderate activity on HIV-1 IN. Bergenin was inactive on both enzymes. The aqueous and methanol extracts were non-toxic in a HeLaP4 cell line at a concentration of 400 μg/ml. © 2005 Elsevier Ireland Ltd. All rights reserved.
bergenin; bridelia micranthra extract; catechin; combretum molle extract; elaodendron transvaalensis extract; Euphorbia extract; gallic acid; integrase; methanol; mucuna coriacea extract; peltophorum africanum extract; plant extract; protocatechuic acid; ribonuclease H; Ricinus communis extract; RNA directed DNA polymerase; sutherlandia frutescens extract; tannin; unclassified drug; vernonia stipulacea extract; virus enzyme; ziziphus mucronata extract; antiviral activity; article; Asteraceae; Celastraceae; Combretaceae; Combretum; controlled study; drug isolation; drug screening; enzyme activity; esterification; Euphorbia; human; human cell; Human immunodeficiency virus 1; IC 50; jujube; legume; medicinal plant; Rhamnaceae; Ricinus communis; South Africa; velvet bean; Vernonia; Anti-HIV Agents; Cell Survival; Combretum; DNA, Viral; Ethanol; HIV Integrase; HIV Integrase Inhibitors; HIV-1 Reverse Transcriptase; Humans; Medicine, African Traditional; Plant Extracts; Plants, Medicinal; Reverse Transcriptase Inhibitors; Solvents; South Africa; Tumor Cells, Cultured; Water; Combretaceae; Combretum; Combretum molle; Fabaceae; Human immunodeficiency virus; Human immunodeficiency virus 1; Peltophorum; Peltophorum africanum