Evaluation of the Antimalarial Activity of Crude Extract of Eucalyptus globulus Labill. Leaf against Plasmodium berghei in Mice

Traditional medicinal plants are used as a common source of developing new and effective antimalarial drugs. E. globulus leaf has been used in the traditional management of malaria in different countries, including Ethiopia. However, there is no in vivo study done on the antimalarial activity of the plant. Thus, this study aimed to evaluate the antimalarial activity of crude extract of E. globulus Labill. leaf in P. berghei -infected mice.Method The fresh leaves of E. globulus were collected, washed, air-dried, and made as coarse powder. Either sex of mice aged 6 to 8 weeks was used in the experiment. The antimalarial activity of the crude extract was tested in four-day suppressive, curative (Rane's), and prophylactic (repository) tests. The parameters like level of parasitemia, packed cell volume, body weight, rectal temperature, and mean survival time were recorded. The analysis of the data was done with SPSS version 20 with a 95% confidence interval in one-way ANOVA followed by Tukey's post hoc test.Results In all three antimalarial test models, the extract of leaf of E. globulus at all three doses suppressed the level of parasitemia significantly ( p < 0.001), increased survival time ( p < 0.05 to p < 0.001), and prevented a decrease in body weight as compared to the negative control. The middle and large doses of the extract also decreased loss of body temperature ( p < 0.05 to p < 0.001) compared to the negative control. Reduction of packed cell volume was prevented within the three test doses of the extract in both curative and prophylactic tests and middle and large doses in the 4-day suppressive test compared to the negative control.Conclusion The crude extract of the plant showed promising antimalarial activity. This supports the traditional use and the in vitro test result of the plant.