Vol. 2, Issue 6, Part B (2016)

Abstract
Microbial infections are major public health problems in the developing countries. Infectious disease consider as the most cause of death for approximately one-half of all deaths in tropical countries. This study was carried out to investigate the in-vitro antibacterial activity of Acacia nilotica methanolic fruits extract against clinical isolates performed by cup-plate agar diffusion method against 5 Gram negative bacteria Escherichia coli, Shigella flexneri, Salmonella typhi, Pseudomonas aeruginosa, and Klebsiella pneumonia and 2 Gram positive bacteria, Listeria monocytogenes and Bacillus cereus. The methanolic extract exhibited inhibitory effects against most of the tested microorganisms with zone of inhibition ranging from (11-39 mm). The largest inhibition zone were obtained from the methanolic extract of Acacia nilotica (fruits) against the Gram negative Salmonella typhi (39mm) in 100 mg/ml concentration, and Gram positive Bacillus cereus (30mm) in 100 mg/ml concentration comparison with Gentamicin (10μg/disc). These studies conducted for A. nilotica (fruits) was proved to have potent activities against clinical isolated bacteria in vitro and was considered as treatment of several bacterial and viral infections.