In vitro screening of some Strychnos species for antiplasmodial activity

The antiplasmodial activity of crude extracts of 19 species of Strychnos (Loganiaceae) was assessed in vitro against a chloroquine-susceptible strain of Plasmodium falciparum. For each species, ethyl acetate (EtOAc) extracts were analysed and, for the most active species, methanolic (MeOH) extracts were also tested. Among them, Strychnos variabilis De Wild. seemed to be very promising (inhibitory concentration 50% (IC50) < 5 μg/ml) whereas two other species, Strychnos gossweileri Exell and Strychnos mellodora S. Moore, could be interesting (IC50 < 15 μg/ml) in further antimalarial studies.