Antiplasmodial Potential and Phytochemical Evaluation of Aqueous Root Extract of a Nigerian Medicinal Apocynaceae Plant

Abstract

The increasing resistance of the malaria parasite to currently used antimalarial medicines has intensified the research for new novel antimalarial drug leads from natural sources. This study was carried out to evaluate the antiplasmodial potential, phytochemical composition and toxicity status of aqueous root extract of Alstoniaboonei (Apocynaceae), a medicinal plant used in treating malariain Nigeria and other African countries. The extract showed substantial dose dependent antiplasmodial activity as indicated by the, suppressive (40.18%, 55.72% and 61.55% for 100, 200 and 400 mgkg -1 body weights), prophylactic (51.39%, 65.27% and 68.35% for 100, 200 and 400 mgkg -1 body weights), and curative (48.63%, 59.59% and 60.88% for 100, 200 and 400 mgkg -1 body weights) effects on Plasmodium berghei infected albino mice. The antiplasmodial activity was significantly different compared to the negative control at P < 0.05.Chemical compounds obtained from the phytochemical evaluation of the extract include tannins, flavonoids, steroids, phenols, alkaloids, saponins, glycosides and terpenoids. There were no observed signs of toxicity in all the oral doses tested on albino mice. It was concluded that the extract contains important active antimalarial compounds that are not toxic and should be further investigated for antimalarial drug development.