Antibiotic susceptibility profiles of ropy slime-producing Leuconostoc mesenteroides isolated from cooked meat products

The transfer of antibiotic resistance via the food chain is a global concern. Nevertheless, more attention is required to non-pathogenic strains, such as spoilage bacteria, which could transmit genes to pathogens. Although Lactic Acid Bacteria are microorganisms generally recognized as safe, Leuconostoc mesenteroides may reach and maintain high concentration levels on the surface of cooked products and ready-to-eat products throughout the entire shelf life. It is therefore important to consider the possibility for this species to carry antibiotic- resistance genes. The present research deals with the antibiotic susceptibility profile of strains of L. mesenteroides, isolated from vacuum packaged cooked meat products. In this study, the antimicrobial susceptibility of L.mesenteroides, previously isolated from cooked ham, was investigated through disk diffusion assay according to CLSI standards. Isolated strains from ready-to-eat food show high levels of resistance to ampicillin and methicillin and, according to a settled panel of 21 antibiotics, the antibiotic resistance was demonstrated for the 50% of the tested molecules.