Antibacterial Activity of Oregano (<i>Origanum vulgare</i> L.) Essential Oil Vapors against Microbial Contaminants of Food-Contact Surfaces

• Main Authors: Loris Pinto (Author), Salvatore Cervellieri (Author), Thomas Netti (Author), Vincenzo Lippolis (Author), Federico Baruzzi (Author)
• Format: Book
• Published: MDPI AG, 2024-04-01T00:00:00Z.
• Subjects: article
• Online Access: Connect to this object online.

Summary

The antimicrobial effect of eight essential oils' vapors against pathogens and spoilage bacteria was assayed. <i>Oreganum vulgare</i> L. essential oil (OVO) showed a broad antibacterial effect, with Minimum Inhibitory Concentration (MIC) values ranging from 94 to 754 µg cm⁻³ air, depending on the bacterial species. Then, gaseous OVO was used for the treatment of stainless steel, polypropylene, and glass surfaces contaminated with four bacterial pathogens at 6-7 log cfu coupon⁻¹. No viable cells were found after OVO treatment on all food-contact surfaces contaminated with all pathogens, with the exception of <i>Sta. aureus</i> DSM 799 on the glass surface. The antimicrobial activity of OVO after the addition of beef extract as a soiling agent reduced the <i>Sta. aureus</i> DSM 799 viable cell count by more than 5 log cfu coupon⁻¹ on polypropylene and glass, while no viable cells were found in the case of stainless steel. HS-GC-MS analysis of the headspace of the boxes used for the antibacterial assay revealed 14 different volatile compounds with α-Pinene (62-63%), and p-Cymene (21%) as the main terpenes. In conclusion, gaseous OVO could be used for the microbial decontamination of food-contact surfaces, although its efficacy needs to be evaluated since it depends on several parameters such as target microorganisms, food-contact material, temperature, time of contact, and relative humidity.

Item Description

10.3390/antibiotics13040371
2079-6382