RESUMO
Background: Current malaria treatment is associated with continued development of drug resistance. Thus, there is a need to develop safe and effective new treatments from different sources. Solanum nigrum L. (Solanaceae) is a plant used for the treatment of malaria in Ethiopian traditional medicine. This study was aimed at evaluating of antimalarial activity of the crude extract and fractions of S. nigrum L. (Solanaceae) leaves against P. berghei infection in mice. Method: Both prophylactic and suppressive models were used in evaluating antimalarial activity using the ANKA Plasmodium strain. In these models, male mice were randomly grouped into eleven groups (n = 5). Mice in group I were given 4% Tween-80, mice from group II up to X were given 100, 200, and 400 mg/kg of plant extract, and the last group (XI) was treated with chloroquine (25 mg/kg). Data were analyzed using one-way ANOVA followed by post hoc Tukey's multiple comparison test. Results: Crude extract of leaves of S. nigrum showed chemosuppression of 30.68 (P < 0.05), 42.42 (P < 0.01), and 50.75% (P < 0.001) at 100, 200, and 400 mg/kg doses of the extract, respectively. At doses of 100, 200, and 400 mg/kg, the chloroform fraction produced a chemosuppressive effect of 40.15% (P < 0.01), 53.78% (P < 0.001), and 65.15% (P < 0.001) and a chemoprophylactic effect of 42.7% (P < 0.05), 51.84% (P < 0.001), and 67.17% (P < 0.001) when compared with negative control. In the suppressive model, the ethyl acetate fraction demonstrated a mean chemosuppression of 56.81% (P < 0.001), 65.9% (P < 0.001), and 70.83% (P < 0.001). Similarly, in the prophylactic model, the fraction showed suppression of 42.70% (P < 0.05), 53.11% (P < 0.001), and 71.03% (P < 0.001) at 100, 200, and 400 mg/kg doses. On the acute oral toxicity test, the extracts were safe at 2 g/kg dose. Conclusion: S. nigrum L. has antimalarial activity and supports the traditional medical practice.