Effect of NaCl addition on the antibacterial effectiveness of acetic acid and its salts against pathogenic bacteria

Abstract

The effect of acetic acid or its salts (sodium, potassium, and calcium acetate), with or without NaCl, against pathogenic bacteria was investigated in laboratory media. Three pathogens (Escherichia coli O157: H7, Salmonella Typhimurium, and Listeria monocytogenes) were inoculated into either Luria-Bertani broth (LB) or LB with 3% NaCl containing 0.1 M acetic acid, 0.1 M sodium acetate, 0.05 M calcium acetate, or 0.1 M potassium acetate, and then incubated at room temperature. The effect of acetic acid or its salts combined with NaCl in LB containing organic compounds revealed an antagonistic effect against S. Typhimurium, no significant effect in E. coli O157: H7, and a synergistic effect in L. monocytogenes. When S. Typhimurium was treated with acetic acid or its salts combined with NaCl, there was a lower reduction in the number of cells and reduced damage to the membrane. Thus, in our study, NaCl increased the resistance of S. Typhimurium to acetic acid and its salts by reducing cell membrane damage. Therefore, further studies are required to understand the mechanisms associated with acetic acid and its salts combined with NaCl against pathogenic bacteria and develop appropriate management methods for food processing. © 2020 Elsevier Ltd