EVALUATING THE ANTIBACTERIAL ACTIVITY OF AZADIRACHTA INDICA EXTRACTS ON ESCHERICHIA COLI AND SALMONELLA SPP.

Abstract

The emergence of antibiotic-resistant bacteria has prompted the search for alternative sources of antibacterial agents. Azadirachta indica (neem) leaf extract has been used extensively as folk medicine for various diseases. This study aimed to evaluate the antibacterial activity of neem leaves ethanol extract against Escherichia coli and Salmonella spp. and to compare its activity with colistin sulphate. Ethanol extracts of varying concentrations (12.5%, 25%, and 50%) were prepared and tested against test organisms using agar diffusion method. The study showed significant antibacterial activity against E. coli and Salmonella spp. However, neem leaves extract was not active against all pathogenic bacteria tested. The extracts have activity against some gram-positive and gram-negative bacteria, and the largest zone of inhibition was recorded against Bacillus cereus. The study recommends the extensive studies of neem leaves to yield cost-effective antibiotics for the future