ABSTRACT
Background:Malaria caused by the parasite Plasmodium falciparum is an acute disease which kills an estimated 863;000 people per year according to the WHO report of 2009. The fight against malaria is faced with the occurrence of widespread resistance of P. falciparum. The search for plant-derived antimalarial drugs has great importance in this regard. Thus this study evaluates the toxicity and antimalarial activity of extracts of Clerodendrum myricoides; Dodonia angustifolia and Aloe debrana. Method: Acute and sub acute toxicity studies of the extracts were carried out by giving up to 3000mg/kg to noninfected mice. Weight loss; change in general behavior and mortality were used as indicators of toxicity. Doses of 200; 400 et 600mg/kg/day of each extract of C.myricoides; D. dodonia and A.debrana were given orally to Plasmodium berghei infected mice following the four-day suppressive test procedure. Results: None of the extracts caused symptoms of toxicity at the given doses. Each extract showed variable level of parasitaemia suppression in dose related manner. Methanol extract of C. myricoides leaves exerted 82.50suppression at the dose of 600mg/kg. The methanol extract of the root of D. angustifolia showed the highest (84.52) suppression of parasitaemia at the dose of 600mg/kg. Furthermore; methanol extract of A. debrana induced 73.95suppression; whereas its water extract exerted 54.36suppression of parasitaemia. Conclusion: Crude extracts of C. myricoides; D. angustifolia and A.debrana caused strong activities against P. berghei indicating that they contain some chemical constituents that possibly lead to antimalarial drug development