Anti-Plasmodial Screening of Selected Medicinal Plants Used in the Treatment of Malaria Among the Ukambani Tribes of Kenya

Malaria is one of the top neglected tropical diseases affecting mostly African sub-Saharan region, coupled with the high spread of drug resistant Plasmodium falciparum and lack of effective vaccines.These have posed for an urgent demand for the development of a novel compound with an antiplasmodial activity from plant origin that will be therapeutic against the lethal strain of Plasmodium parasites.In this study, eight plants from Kenyan ethnomedicine were selected.The choice of these plants was affected by their use in the management of malaria in a traditional way.The plant were extracted for their bioactives using polar and non polar solvent and the result showed that polar extract of Rhamnus prinoid and Ceasalpinea volkensii had the highest percentage yield of 21.14% and 20.41%, while the non polar extract of Croton macrostachyus and Macroglossia pyrifolia had the least percentage yield recovery with 4.14% and 2.93%, respectively.The extract were further subjected to a qualitative phytochemical analysis and the result showed the presence of the following phytocompounds; alkaloids, phenols, flavonoids, anthroquinones, saponins, coumarins, essensial oils and terpenes.The extract were finally subjected to in-vitro antiplasmodial analysis and the result revealed that Ceasalpinea volkensii methanol extract, Vernonia lasiopus methanol extract and Macroglossia pyrifolia methanol extract had the IC 50 values of 2.37±1.70µg/ml, 4.50±1.75µg/ml, 2.39±1.95µg/ml, with an excellent antiplasmodial activity.While, the non polar extract of Rhamnus pyrifolia dichloromethane, Albizia gumifera dichloromethane with IC50 of 16.45±0.55µg/ml and 8.20±1.45µg/mlwith a promising antiplasmodial activity.While the extract of Croton macrostachyus dichloromethane, Ceasalpinea volkensii and Albizia gumifera methanol were all found to be in-active even at higher concentration.The antiplasmodial activity of the extracts was all found to have a strong correlation in all the polar extract and at variance with that of the non polar solvent extract.It can be concluded, that polar extract of Vernonia lasiopus, Ceasalpinea volkensii, Rhamnus prinoid, Clausina anesatata and Croton macrostachyus could be utilized as a potential source for the novel anti-malarial drug.