Abstract

Zehenria scabra is among the Ethiopian folk medicine for malaria like fever and other infectious diseases. But it lacks apposite pharmacological investigation. This study aimed at evaluating the antimalarial activity and safety profile of Z. scabra. Plasmodium berghei was used for induction of malaria, kept in a refrigerator and maintained by serial passage of blood from mouse to mouse. The crude extract, chloroform and ethylacetate fractions were obtained from air dried aerial part of Z. scabra. Activity was tested in vivo against chloroquine-sensitive strain of P. berghei by measuring the parasite load using light microscope. 80% methanolic extract yield was 18%. The 2000 mg/kg body weight of the crude extract was devoid of any signs of toxicity. Crude extract of the plant provided 62.5, 72.85 and 76.01% suppression with increasing doses of 100, 200 and 400 mg/kg, respectively. Two solvent fractions of the plant have been also assessed for the same parameter. The ethyl acetate fraction was found to be the most active of all with suppression of 71.88% for 25 mg/kg, 62.47% for 50 mg/kg and 77.62% for the 400 mg/kg dose. Similarly, the 25, 50 and 100 mg/kg of chloroform fractions had also shown 53.57, 73.95 and 61.31%, respectively. In the case of survival of the animals, after 7 days of treatment groups, the ethyl acetate groups had shown better outcome which was 100% for the medium (50 mg/kg) and maximum doses (100 mg/kg). Activities as well as safety studies of this plant confirm the ethnopharmacological usefulness as antimalarial, thus its usage by the folkloric medicine. It can also be used as a base for characterization of some active compounds that could be used as markers for standardization of the extracts for use as traditional antimalarial.

Key words: Antimalarial acitivy, Plasmodium berghei, Zehneria scabra, parasitemia.