Antimalarial Activity of the 80% Methanol Leaf Extract and Solvent Fractions of Stephania abyssinica (Dill. & A. Rich.) Walp. against Plasmodium berghei Infection in Mice
Malaria continues to be a global public health threat. In Africa, malaria accounts for a substantial morbidity and mortality. The emergence of drug resistant malaria parasites and subsequent decrement in effectiveness of current antimalarial medications have complicated malaria control. This urged developing an effective alternative antimalarial agent. Leaves and root of Stephania abyssinica (Dill. & A. Rich.) Walp. is traditionally used for the treatment of malaria in east African countries such as Ethiopia and proved for its in vitro antimalarial efficacy. Hence, this study aimed at evaluating the antimalarial activity of S. abyssinica. Cold maceration technique was employed to prepare the 80% methanol crude extract followed by fractionation using n-hexane, chloroform and ethyl acetate. The in vivo antimalarial property of different dose levels (100, 200 and 400 mg/kg/day) of the hydroalcoholic extract and solvent fractions were investigated using prophylactic and 4-day suppressive mice models, against Plasmodium berghei (ANKA strain). Highest (400 mg/kg) doses of the hydroalcoholic extract and solvent fractions (hexane, chloroform and ethyl acetate) exhibited a statistically significant (p < 0.001) chemosuppressive activities. The chloroform fraction revealed the highest chemosuppresion (55.80%) and chemoprophylactic (57.59%) potency in 4-day suppressive and prophylactic tests, respectively, at 400 mg/kg dose level. Furthermore, 400 mg dose of the chloroform fraction significantly prevented malaria associated haemolysis as compared to vehicle treated group in both prophylactic (p < 0.05) and suppressive (p < 0.01) models. In conclusion, the current study gave evidence that the plant has a potential antimalarial activity against P. berghei, which upholds traditional claims and justifies a need to undertake advanced pharmacological and toxicological investigations.