Investigating the In-vivo Antiplasmodial Properties of Aqueous Extract of Moringa oleifera Lam (Moringaceae) Leaves

Aim: The study investigated Moringa oleifera Lam (Moringaceae), for its in-vivo antiplasmodial properties, using a murine model involving Plasmodium berghei.
Study Design: Experimental.
Places of Study and Duration: Department of Pharmaceutical Chemistry, KNUST, Department of Immunology, NMIMR and Department of Animal Experimentation, NMIMR, May – November, 2013.
Methodology: Phytochemical investigation was conducted on powdered plant material and aqueous leaf extract (ML), to determine the presence of secondary metabolites using standard methods. Using 4-day suppressive and 7-day curative tests respectively, ML at 250-1000 mg/kg, was evaluated for in-vivo antiplasmodial activity in P. berghei infected male ICR mice (25-30 g), using Artemether-Lumefantrine (A/L) at 4 mg/kg as reference drug. The effect of ML on the body weights and the survival of the mice, as well as the effect on improvement in clinical signs was also monitored.
Results: ML extract was found to contain alkaloids, saponins, flavonoids and tannins. The extracts (250-1000 mg/kg) produced significant reduction in parasitemia in the four-day suppressive test (F6,49 = 4.309; p =.0014). However, 250 mg/kg (69.31%; p< .001) and 500 mg/kg (77.26%; p< .001) extracts exhibited relatively higher activities compared to 750 mg/kg (25.28%; p< .001) and 1000 mg/kg (07.12%; p> .05). In the curative test, similar results were obtained with significant parasitemia reduction for 250 mg/kg (AUC = 52.52±6.732; p< .01) and 500 mg/kg (AUC = 49.62 ± 3.804; p< .01) compared to the positive control group (AUC = 101.3±14.32). Piloerection, lethargy and decreased locomotion were observed to be progressive in all infected experimental groups except A/L. Survival data showed that, although 750 mg/kg and 1000 mg/kg groups recorded relatively higher mortalities, statistical analysis didn’t indicate significant difference.
Conclusion: ML extract demonstrated in-vivo antiplasmodial activity; probably due to the alkaloids, saponins, flavonoids and tannins in its composition.