Phytomedicine. 2002 Jan; 9(1): 62-8.

Antiviral activity of Rwandan medicinal plants against human immunodeficiency virus type-1 (HIV-1).

Cos P, Hermans N, De BT, Apers S, Sindambiwe JB, Witvrouw M, De CE, Vanden BD, Pieters L, Vlietinck AJ.

Faculty of Pharmaceutical Sciences, University of Antwerp, Belgium.

Selected plants used in Rwandan traditional medicine for the treatment of infections and/or rheumatoid diseases were investigated for antiviral activity in vitro against human immunodeficiency virus type-1 (HIV-1). Of the 38 tested 80% ethanolic extracts, belonging to plants of 21 different families only the extracts from the leaves of Aspilia pluriseta (Asteraceae) and Rumex bequaertii (Polygonaceae) had interesting selectivity indices (SI = ratio of the 50% cytotoxic concentration to the 50% effective antiviral concentration) higher than 1. Further fractionation of the initially antivirally inactive ethanolic extract of Tithonia diversifolia, however, led to an aqueous fraction with a high anti-HIV-1 activity (SI > 461), indicating that the cytotoxicity of some plant components may mask the antiviral properties of the active plant substances in total plant extracts.