Antibacterial activity of <i>Rosmarinus officinalis</i> L. and <i>Thymus vulgaris</i> L. essential oils and their combination against food-borne pathogens and spoilage bacteria in ready-to-eat vegetables

<p>The antibacterial activity of <i>Rosmarinus officinalis</i> L. and <i>Thymus vulgaris</i> L. essential oils (EOs), and their combination against food-borne and spoilage bacteria (<i>Listeria monocytogenes</i>, <i>Salmonella enteritidis</i>, <i>Yersinia enterocolitica</i>, <i>Escherichia coli</i> and <i>Pseudomonas</i> spp.) was determined. The EOs inhibitory effect was evaluated both <i>in vitro</i> by using the disk diffusion assay and the minimum inhibitory concentration (MIC) determination, and <i>on food</i> by using an artificially contaminated ready-to-eat (RTE) vegetables. The results showed that the lowest MIC values were obtained with <i>R. officinalis</i> and <i>T. vulgaris</i> EOs against <i>E. coli</i> (4 and 8 μL/mL, respectively). The incorporation of the EOs alone or their combination in RTE vegetables reduced the viable counts of all the tested strains. Lastly, in the <i>on food</i> study we simulated the worst hygienic conditions, obtaining results that can be considered a warranty of safety.