SCREENINC OF EXTRACTS OF SOME NICERIAN MEDICINAL PLANTS FOR TRYPANOCIDAL ACTIVITY

Abstract

Extracts from various parts of Annona senegalensis plant , stem bark of Enantia chlorantha and Okoubaka aubrevellei and leaf of Calotropis procera and mitracapus scabra were screened for trypanocidal activity in albino mice and white rats infected with Trypanosoma brucei brucei. Both the crude and the partially purified forms of aqeous extract of Annona senegalenisis leaf satisfactorily cleared trypanosomes from the systems of the experimentally infected animals at the dose of 200mgkg 1 body weight. There was also no sign of the presence of parasites in the cerebrospinal fluid of the treated mice. The treated animals survived for more than five months post treatment. Acute toxicity study showed that the extract is non-toxic. Phytochemical screening revealed the presence of Tannin, Saponin and phlobatannin. The aqeous and alcohol ic extracts of the root bark and the stem bark showed no appreciable trypanocidal activity even at a high dose of 350mg kg 1 body weight. Enantia chlorantha at a dose of 100mg k·g 1 body weight brought a very high level of parasitemia load down considerably. However, the parasitemia later rose up again and killed the animals two weeks post treatment. The remaining plants screened showed no trypanocidal activities at the doses used.