Screening of Tanzanian medicinal plants against Plasmodium falciparum and human immunodeficiency virus.

Medicinal plants used to treat infectious diseases in Bunda district, Tanzania, were screened for activity against Plasmodium falciparum and Human Immunodeficiency Virus Type 1 (HIV-1, IIIB strain) and Type 2 (HIV-2, ROD strain). Antiplasmodial activity was observed for the 80 % MeOH extract of Ormocarpum kirkii (root; MIC = 31.25 microg/mL), Combretum adenogonium (leaves), Euphorbia tirucalli (root), Harrisonia abyssinica (root), Rhynchosia sublobata (root), Sesbania sesban (root), Tithonia diversifolia (leaves), and Vernonia cinerascens (leaves; MIC value of 62.5 microg/mL). With regard to HIV, 80 % MeOH extracts of Barleria eranthemoides (root), Combretum adenogonium (leaves and stem bark), Elaeodedron schlechteranum (stem bark and root bark), Lannea schweinfurthii (stem bark), Terminalia mollis (stem bark and root bark), Acacia tortilis (stem bark), Ficus cycamorus (stem bark) and Indigofera colutea (shoot), as well as H2O extracts from Barleria eranthemoides (root), Combretum adenogonium (leaves and stem bark), and Terminalia mollis (stem bark and root bark) exhibited IC50 values below 10 microg/mL against HIV-1 (IIIB strain). The highest anti-HIV-1 activity value was obtained for the B. eranthemoides 80 % MeOH root extract (IC50 value 2.1 microg/mL). Only a few extracts were active against HIV-2, such as the 80 % MeOH extract from Lannea schweinfurthii (stem bark) and Elaeodedron schlechteranum (root bark), showing IC50 values < 10 microg/mL.