Evaluation of in vivo antitrypanosomal activity of selected medicinal plant extracts

Abstract

This study was based on the observation that traditional practitioners in Kenya use plant based extracts for the treatment of parasitic diseases. This necessitated the need to investigate the potential of such plants. Four plants (Kigelia africana, Artemesia annua, Bidens pilosa and Azadirachta indica) were selected for investigation against African human trypanosomiasis. The methanol, dichloromethane and aqueous extracts of these plants were administered intraperitoneally to Swiss white mice that had previously been inoculated withTrypanosoma brucei rhodesiense KETRI 3798. The parasitaemia, packed cell volume and body weight in each mouse was monitored for 60 days. This was done in parallel with control mice, which had been given water and ethanol (Negative control) and standard drugs; Melarsoprol and Suramin (positive control) respectively. Among the extracts tested, the dichloromethane extract prepared from the fruits of Kigelia Africana, tested at a dose of 2000 mg/kg was effective, curing 60% of the animals treated. The other extracts did not show significant anti trypanosomal activity. The treated positive controls (Melarsoprol and Suramin at dose of 3.6 and 5 mg/kg respectively), showed 100% survival and cleared parasites. These results show that K. africana has great potential as anti trypanosomiasis agent, which could be developed into an alternative drug to complement treatment of trypanosomiasis. Key words: Antitrypanosomal activity, Kigelia africana, Packed Cell Volume, Human African tryponosomiasis.