Variability in Listeria monocytogenes susceptibility to benzalkonium chloride

Introduction: Listeria monocytogenes is a gram-positive pathogenic bacterium that causes severe foodborne listeriosis in humans, transmitted through contaminated foods, with high hospitalization and mortality rates, particularly affecting vulnerable groups: the elderly, immunocompromised individuals, and pregnant women [1]. Quaternary ammonium compounds, such as benzalkonium chloride, are widely used as biocides for surface disinfection in various settings, including food processing environments. These compounds have the capability to disrupt the charge distribution of microbial membrane bilayers, thereby leading to their deregulation [2].