Effects of Selected Essential Oils on Listeria monocytogenes in Biofilms and in a Model Food System

• Published in: Foods Vol. 12; no. 10; p. 1930
• Main Authors: Vidaković Knežević, Suzana, Knežević, Slobodan, Vranešević, Jelena, Kravić, Sneẑana Ž, Lakićević, Brankica, Kocić-Tanackov, Sunčica, Karabasil, Nedjeljko
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 09.05.2023; MDPI
• Subjects: Antibacterial activity; antibiofilm activity; antimicrobial activity; Antimicrobial agents; Bacteria; Biofilms; Chemical composition; Essential oils; Ethanol; Experiments; Food composition; Food contamination & poisoning; Food science; Gas chromatography; Listeria; Listeria monocytogenes; Low concentrations; Mass spectrometry; Mass spectroscopy; Meat industry; minced pork meat; Minimum inhibitory concentration; Nutrient availability; Nutrients; Oils & fats; Oregano; oregano essential oil; Physiology; Polystyrene; Polystyrene resins; Scanning electron microscopy; Temperature dependence; Thyme; thyme essential oil; United Kingdom > UK; Serbia; France; Germany; Listeria monocytogenes; minced pork meat; antimicrobial activity; oregano essential oil; thyme essential oil; antibiofilm activity
• ISSN: 2304-8158; 2304-8158
• DOI: 10.3390/foods12101930

The composition of 18 essential oils was determined using gas chromatography-mass spectrometry, and their antilisterial activity was evaluated by the disk diffusion method, followed by the determination of the minimum inhibitory and minimum bactericidal concentrations. The most active essential oils were oregano, thyme, cinnamon, winter savory, and clove, with MIC values ranging from 0.09 to 1.78 µL/mL. We investigated the biofilm-forming potential of on polystyrene at 5 °C, 15 °C, and 37 °C in three different media. The formation of biofilm was found to be dependent on the temperature and the availability of nutrients. After treatment with selected essential oils, the reduction in biofilm biomass was in the range of 32.61% and 78.62%. Micromorphological changes in the treated by oregano and thyme essential oils were observed in the form of impaired cell integrity and cell lyses by using scanning electron microscope. Oregano and thyme essential oils (MIC and 2MIC) significantly ( < 0.05) reduced the population of in minced pork meat during storage at 4 °C. In conclusion, the obtained results indicated the good activity of some selected essential oils on , with bacteriostatic, bactericidal, and antibiofilm effects at very low concentrations.