Trypanocidal Properties of Aqueous Leaf Extract of Morinda lucida.

Abstract

This study was designed to evaluate the trypanocidal properties of hot and cold aqueous leaf extracts of Morinda lucida in mice infected with Trypanosoma brucei brucei. The hot aqueous extracts of the leaf at 100, 200, 300, 400 and 500 mg kg-1 body weight per day were administered to the test groups intraperitoneally 72 h post infection. The negative control was treated with normal saline. The most effective dose (400 mg kg-1 b.wt.) of both hot and cold extracts were administered on another group of infected mice to re-ascertain its efficacy while 3.5 mg kg-1 body weight single dose of berenil was administered on positive control group. To establish the safety of the extract at higher doses, 1000 mg kg-1 body weight of both hot and cold extracts were administered on parasite-free mice, while 400 mg kg-1 body weight of normal saline was given to the negative control group. The level of parasitemia, variation in weight and percentage Packed Cell Volume (%PCV) in the different groups were monitored throughout the period of study. The mice treated with 400 mg kg-1 body weight of hot and cold extract lived upto 34 and 50 days post infection with minimal and zero level of parasitemia, respectively while mice in the negative control died on the 12th and 14th day post infection. There was significant (p<0.05) improvement in packed cell volume and weight of the treated mice after the period of treatment. No signs of toxicity were observed in the group administered 1000 mg kg-1 body weight. The results obtained in this study show that aqeous extract of Morinda lucida possesses antitrypanosomal activity.