Assessment of Antimalarial Activity againstPlasmodium falciparumand Phytochemical Screening of Some Yemeni Medicinal Plants

Abstract

Developing countries, where malaria is one of the most prevalent diseases, still rely on traditional medicine as a source for the treatment of this disease. In the present study, six selected plants (Acalypha fruticosa,Azadirachta indica,Cissus rotundifolia,Echium rauwalfii,Dendrosicyos socotranaandBoswellia elongata) commonly used in Yemen by traditional healers for the treatment of malaria as well as other diseases, were collected from different localities of Yemen, dried and extracted with methanol and water successfully. The antiplasmodial activity of the extracts was evaluated against fresh clinical isolates ofPlasmodium falciparum. The selectivity parameters to evaluate the efficacy of these medicinal plants were measured byin vitromicro test (Mark III) according to World Health Organization (WHO) 1996 & WHO 2001 protocols of antimalarial drug tests. Among the investigated 12 extracts, three were found to have significant antiplasmodial activity with IC50values less than 4 µg/ml, namely the water extracts ofA. fruticosa,A. indicaandD. socotrana. Six extracts showed moderate activity with IC50values ranging from 10 to 30 µg/ml and three appeared to be inactive with IC50values more than 30 µg/ml. In addition, preliminary phytochemical screening of the methanolic and aqueous extracts indicated the presence of saponins, tannins, flavonoids, terpenoids, polysaccharides and peptides.