Trypanocidal potentials of Azadirachta indica seeds against Trypanosoma evansi

The trypanocidal potentials of Azadirachta indica seeds methanolic extract (NSME) against Trypanosoma evansi was examined. In vitro studies with the NSME 100 mg/ml, 50 mg/ml and 25 mg/ml immobilized the parasites within 3 min, 8 min and 14 min respectively. In vivo experiments in infected rats at various dosage with NSME expressed transient ability of clearing the parasites in the infected blood. Thin layer chromatographic (TLC) separations of the NSME gave 4 fractions in toluene and ethyl acetate [1:0.25] solvent system on TLC of which only fraction 3 (F3) retained the trypanocidal properties which cleared the parasites in the infected rats for 14 days. The high performance liquid chromatography (HPLC) analysis of NSF F3 revealed the presence of Azadirachtins A and B as active components. The NSF F3 manifested prophylactic potency at a dose of 500 mg/kg/day × 3/7. The packed cell volume (PCV) of the group administered 500 mg/kg/day × 3/7 NSF F3 and normal control (NC) had no significant difference. The NSF F3 also inhibited Phospholipase A2 enzyme in a dose-dependent pattern.