Phytochemical Screening and <i>In Vitro</i> Antitrypanosomal Activity of the Aerial Parts of <i>Artemisia abyssinica</i> Against <i>Trypanosoma congolense</i> Field Isolate

Abstract

African trypanosomiasis is a major public health problem having serious economic implications affecting both human and agricultural development. The present work dealt with phytochemical screening and in vitro antitrypanosomal activity testing of the hydromethanolic and dichloromethane (DCM) extracts of the aerial parts of Artemisia abyssinica Sch.Bip. ex A.Rich. against Trypanosoma congolense field isolate. The in vitro assay was conducted by incubating a mixture of infected blood and extracts at concentrations of 4, 2 and 0.4 mg/ml coupled with infectivity test in which a mixture of infected blood was inoculated to healthy mice. Phytochemical screening showed the presence of alkaloids, flavonoids, tannins, polyphenols, and cardiac glycosides in the hydromethanolic extract, and terpenoids, polyphenols and phytosteroids in the DCM extract. The result evidenced that the DCM extract had immobilized trypanosomes after 18 and 40 min of incubation at 4 and 2 mg/ml, respectively, while the hydromethanolic extract ceased the motility of the parasites after 35 min only at a concentration of 4 mg/ml. In the infectivity test, only 4 mg/ml of  the DCM extract caused loss of infectivity of the parasites to mice. In conclusion, the result obtained from this preliminary investigation renders the plant to be a potential candidate for development of new lead against African trypanosomiasis.

Keywords: Artemisia abyssinica, phytochemical screening, in vitro antitrypanosomal activity, Trypanosoma congolense, crude extracts