In vitro antiplasmodial evaluation of ethanolic and n-hexane extracts of Parinari curatellifolia stem bark

Parinari curatellifolia and other Parinari species are used traditionally in many parts of Africa as a remedy for malaria among other diseases. To ascertain this folkloric claim, the antiplasmodial potential of ethanol extract of Parinari curatellifolia stem bark (EEPCSB) and n-hexane extract of Parinari curatellifolia stem bark (HEPCSB) on Plasmodium falciparum was studied. Parasites were grown in a 96-well plate containing Roswell Park Memorial Institute-1640. The wells were grouped into: control (untreated), artemether-treated, EEPCSB-treated and HEPCSB-treated groups. Treatments were administered to the tune of 10, 20, 40 and 80 µg/ml. Parasitemia was observed by microscopy after 24, 48 and 72h of incubation. EEPCSB and HEPCSB elicited dose and duration-dependent reduction (p<0.05) in parasitemia when compared with the untreated group. The recorded percentage parasite inhibition by the extracts was lower (p<0.05) when compared with artemether. There was no difference (p>0.05) in plasmodium lactate dehydrogenase activity of EEPCSB-treated and artemether-treated groups. Findings from this study show that extracts of P. curatellifolia stem bark, especially EEPCSB, demonstrated excellent inhibitory activities against P. falciparum and can be a good source of compounds for the development of novel antimalarial drugs.