Zingiber officinale (ginger) has been extensively studied for its antibacterial properties. This study evaluated the antibacterial activity of acetone and water extracts of Z. officinale against Gram-positive and Gram-negative bacteria using deep-well diffusion, minimum inhibitory concentration (MIC), potassium ion efflux, and Bradford protein assays. Bacterial strains, including Gram-positive Enterococcus faecalis (ATCC 49533) and Gram-negative Escherichia coli (ATCC 11954), were obtained from the American Type Culture Collection (ATCC). Fresh ginger rhizomes were collected from Alvier Boerdery in Levubu, Louis Trichardt, and a 10 g sample was used for extraction. The MIC values revealed significant inhibition, with the lowest MIC of 0.049 mg/mL recorded against E. coli for the acetone extract. The deep-well diffusion assay demonstrated larger zones of inhibition for water extracts compared to acetone extracts, with Micrococcus luteus exhibiting the highest inhibition zone (27.5 mm). The potassium ion efflux assay confirmed membrane disruption, while the Bradford assay indicated increased protein leakage in treated bacterial strains, suggesting compromised membrane integrity. Tetracycline and amoxicillin were used as positive controls for comparison. These findings highlight Z. officinale as a promising antibacterial agent, warranting further research on its mechanisms of action and potential applications in antimicrobial therapy.

 

Key words: Zingiber officinale, membrane permeability, natural antimicrobials, mechanism of action, potassium ion efflux, protein leakage, pathogenic bacteria.