Antipyretic and antimalarial activities of crude leaf extract and fractions of Enicostema littorale

Abstract

ObjectiveTo evaluate the antiplasmodial and antipyretic activities of whole plant extract and fractions of Enicostemma littorale (E. littorale) for ascertaining the folkloric claim of its antimalarial and antipyretic activities. MethodsThe crude extract (260 – 780 mg/kg) and fractions (chloroform and acqeous; 520 mg/kg) of E. littorale were investigated for antiplasmodial activity against chloroquine-sensitive Plasmodium berghei (P. berghei) infections in mice and for antipyretic activity against dinitrophenol, amphetamine and yeast-induced pyrexia. The antiplasmodial activity during early and established infections as well as prophylactic were investigated. Artesunate (5 mg/kg) and pyrimethamine (1.2 mg/kg) were used as positive controls. Antipyretic activity of the crude extract was also evaluated against dinitrophenol, amphetamine and yeast-induced pyrexia. ResultsThe extract and fractions dose-dependently reduced parasitaemia induced by chloroquine-sensitive P. berghei infection in prophylactic, suppressive and curative models in mice. These reductions were statistically significant (P<0.001). They also improved the mean survival time from 11 to 27 days relative to control (P<0.01 – 0.001). The activities of extract/fractions were comparable to that of the standard drugs used (artesunate and pyrimethamine). On pyrexia induced by dinitrophenol, amphetamine and yeast, the extract caused inhibitions which were statistically significant (P<0.05 – 0.001) and in a dose-dependent fashion. ConclusionsThese plant extracts possess considerable antiplasmodial and antipyretic activities, which justify its use in ethnomedicine.