Abstract

This study was carried out to determine the antibacterial activity of Vernonia amygdalina extracts at concentrations of 30 mg/ml, 60 mg/ml and 90 mg/ml respectively. The bacteria were isolated from meat samples obtained from five (5) designated areas in Sokoto State. The bacteria isolated were Escherichia coli, Salmonella typhi, Pseudomonas aeruginosa, Staphylococcus aureus, Shigella spp and Bacillus subtilis. Agar well diffusion method was used to test the antibacterial activity of the extract at diffusion concentration on the bacteria and the following results were obtained: At 30 mg/ml, Escherichia coli (9 mm), Staphylococcus aureus (7 mm), Pseudomonas aeruginosa (9mm), were susceptible but Bacillus subtilis, Shigella spp and Salmonella typhi were resistant. At 60 mg/ml, Escherichia coli (12 mm), Staphylococcus aureus (10mm) Pseudomonas aeruginosa (11 mm) were susceptible but Bacillus subtilis, Shigella spp and Salmonella typhi were still resistant. However, at 90 mg/ml, activity was only seen in Salmonella typhi (6 mm) among the resistant bacteria, while the rest were still susceptible. However, the activity of the extract increases as the concentration increases. This might be due to the presence of secondary metabolite like Tannins, Saponins, Flavonoids, Steroids and saponin glycosides.