Antimalarial Potential of Methanolic and Aqueous Extracts of Leaves, Root and Stem-Bark of Vitex doniana

Aim: This study was aimed at evaluating the antimalarial potential of methanolic and aqueous extracts of leaves, root and stem bark of Vitex doniana.

Materials and Methods: Apparently healthy parts of V. doniana (leaves, root and stem bark) were obtained from a farm in Abakaliki, Nigeria. They were air dried and milled into powder and were extracted using methanol and water as solvent respectively. Thirty (30) Swiss male albino mice weighing 15-20 g were used for this study. They were acclimatized for 14 days and randomly divided into 10 groups of 3 mice each. The chloroquine resistant Plasmodium berghei (NK 65) used was obtained from the Department of Veterinary Pathology, University of Ibadan. The parasite was maintained by sub-passaging into healthy mice via an intraperitoneal route. Treatment of the animals began 24 hours after infection with the parasite and parasitaemia confirmed. Groups A and B were treated with aqueous and methanol leaf extract of V. doniana respectively. Groups C and D were treated with aqueous and methanol root extract of V. doniana respectively. Groups E and F were treated with aqueous and methanol stem-bark extracts of V. doniana respectively. Groups G, H and I were treated with the standard drugs Artemether, Artesunate and Chloroquine respectively and Group J were administered the vehicle (normal saline) and this group served as the negative control group. The administrations were done once a day for 14 days via the intraperitoneal route. Parasitaemia was monitored in all the groups starting from day 0 to day 14 using thick and thin blood films made from blood obtained from the tail vein of mice.

Results: The infected animals treated with methanol stem bark extract of V. doniana was compared on day 0 and 10, there was a great reduction in parasitaemia level from 5.33±0.58 to 3.33±0.58 as compared to 6.67±1.15 to 43.0 ±2.65 in untreated group and 5.33±0.58 to 5.67±1.15 in Chloroquine treated group.

Conclusion: From the result of this study, it can be said that methanolic extract of V. doniana stem bark is more potent as an antimalarial agent.