Abstract

The fresh leaves of Achyranthes aspera Linn. soaked with water is traditionally used to treat skin infection in Ethiopia. The leaves are also applied traditionally to stop bleeding during cutoff in local people of Ethiopia. The above activities of the plant might be associated with antimicrobial activities. The leaves collected from their wild habitat were air dried under shade and ground into fine powder. The leaf powder was soaked in solvents (1 g: 10 ml) and shacked for 72 h. After filtering, the mixtures were concentrated by using rotary evaporator and the extract was prepared at 50, 100 and 200 mg/ml in 3% Tween 80 for antibacterial test. The disks were loaded with extract solution and allowed to evaporate. Then, the discs were placed on culture bacteria in the Muller Hinton agar and incubated for 24 h. Finally, the inhibition zones were measured in mm. The antibacterial activities and the minimum inhibitory concentration (MIC) test of the extracts were assessed by disk diffusion and agar dilution methods, respectively. Both 80% methanol and chloroform extract of A. aspera leaf showed significantly higher inhibition zone than the negative control, 3% Tween 80, but the extracts inhibition was significantly lower than the standard drugs (chloroamphenicol and ampiciline). Both 80% methanol and chloroform extract of A.  aspera leaf showed MIC on Shigella boydii and Salmonella typhi at 6.25 mg/ml. The minimum bactericidal concentration (MBC) of the 80% methanol and chloroform extract of A. aspera leaf was measured at 6.25 and 12.5 mg/ml on S. boydii and S. typhi, respectively. The bacterial inhibition increased with the 80% methanol and chloroform extracts of A. aspera leaves concentrations. The 80% methanol A. aspera leaf extract which was administered orally with a single dose of 500, 1000 and 2000 mg/kg body weight was not toxic to albino mice.

Key words: Achyranthes aspera, inhibition zone, antibacterial activity, acute toxicity, minimum inhibitory concentration, minimum bactericidal concentration.