Evaluation of the antimalarial activity of aqueous leaf extracts of Casuarina equistifolia and Mangifera indica against Plasmodium berghei in mice
The evaluation of anti-malarial properties of crude leaf extract of Mangifera indica and Casuarina equistifolia were carried out using standard procedures in laboratory mice. The results showed that water extract of M. indica displayed a very good activity against Plasmodium berghei malaria parasites in a dose dependent fashion with a statistically significant difference (p< 0.05) while C. equistifolia extract showed no significant difference (p> 0.05) at all the dose levels chosen in the suppressive test. Furthermore, in the curative, all the test substances were able to reduce the parasitaemia level with a clear significant difference between the treated groups and the control (p< 0.05) although parasites were not totally cleared after termination of treatment. The repository effect of the test substances produced a significant difference (p< 0.05) suppression of parasitaemia, but C. equistifolia failed to prove any repository effect as the parasitaemia level increased to 12.40± 1.91 than the control 11.67±1.56. The test extracts did not prevent body weight loss associated with malaria infection as only the 5mg/kg chloroquine phosphate (CQ) group prevented weight loss. Prevention of toxic effect resulting from treatment was determined based on the LD50 of the extracts to be 891.25mg/kg M. indica and 2884.03mg/kg for C. equistifolia inoculated intraperionneally in mice. The phytochemical screening of the two extracts revealed the presence of tannins, flavonoids, cardiac glycosides, steroids/ terpenoids and carbohydrates. In addition to these, M indica extract contained alkaloids, saponins and anthraquinones.
Keywords: Malaria, Plasmodium berghei, Mangifera indica, Casuarina equistifolia, aqueous extract.