In vitro cytotoxic, antileishmanial and antifungal activities of ethnopharmacologically selected Gabonese plants

The methanolic extract of Polyalthia suaveolens displayed a strong antiproliferative activity against the promastigote form of Leishmania infantum parasites and presented a good antifungal activity on all the tested strains (IC50 < 1 mg/ml). This extract was divided into six fractions: fraction F6 demonstrated a cytotoxic activity stronger than those of the crude extract (IC50 = 0.6 μg/ml), fractions F4 and F5 were devoid of cytotoxicity (IC50 >100 μg/ml) and displayed interesting antileishmanial activity against the intracellular amastigote form of the parasite (IC50 = 5.6 and 12.4 μg/ml), respectively. However, the antifungal activity observed for the crude extract could not be recovered in the corresponding fractions.