Evaluation of Ethnomedical Claims II: Antimalarial Activities Ofgongronema Latifoliumroot and Stem

Methanolic extract and chromatographic fractions of Gongronema latifolium were tested against clinical isolates of Plasmodium falciparum-, P. yoelii nigeriensis-infected mice, chloroquine-sensitive (D6) and chloroquine-resistant (W2) P. falciparum clones. The isolates, characterized as a 1:1 mixture of α-amyrin and β-amyrin cinnamates (1a/1b), lupenyl cinnamate (2) and lupenyl acetate (3), were assayed using the clones. Extract, most active vacuum liquid and column chromatographic fractions had respective ED50 values of 120.85, 32.03, 25.62 mg.kg-1 and IC50 of 36.27, 9.45, 7.05 μg.mL-1, against W2 clones. Lupenyl acetate had 18.96 μg.mL-1, indicating synergistic action of the constituents. Results justified its ethnomedical use for treating malaria.