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

Nat Prod Res. 2019 Dec;33(24):3568-3572. doi: 10.1080/14786419.2018.1482894. Epub 2018 Jun 6.

Abstract

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

Keywords: spp; EOs antibacterial activity; Ready-to-eat products.

MeSH terms

  • Anti-Bacterial Agents / isolation & purification*
  • Anti-Bacterial Agents / pharmacology
  • Escherichia coli / drug effects
  • Food Microbiology*
  • Food Safety
  • Listeria monocytogenes / drug effects
  • Microbial Sensitivity Tests
  • Oils, Volatile / isolation & purification
  • Oils, Volatile / pharmacology*
  • Rosmarinus / chemistry*
  • Thymus Plant / chemistry*
  • Vegetables / microbiology*

Substances

  • Anti-Bacterial Agents
  • Oils, Volatile