Chemical composition and antibacterial effects of some essential oils individually and in combination with sodium benzoate against methicillin-resistant Staphylococcus aureus and Yersinia enterocolitica

Side effects of chemical preservatives and drug resistance have raised interest in use of herbal products. This study aimed to examine the chemical composition and antibacterial effects of Cuminum cyminum, Mentha spicata, and Mentha longifolia essential oils individually and in combination with sodium benzoate against methicillin-resistant Staphylococcus aureus and Yersinia enterocolitica. The essential oils were analyzed by gas chromatography-mass spectrometry. Disc diffusion and microdilution assays were used for in vitro antimicrobial screening. The main components were cumin aldehyde, carvone, and pulegone in C. cyminum, M. spicata, and M. longifolia essential oils, respectively. Antibacterial data analysis showed significant differences between different antibacterial effects of essential oils individually and in combination with sodium benzoate. In terms of individual effects, antibacterial effect of M. longifolia and C. cyminum essential oils were the highest against methicillin-resistant S. aureus and Y. enterocolitica, respectively. The antibacterial effects of sodium benzoate combined with essential oils showed significant differences with the individual effect of sodium benzoate in most cases. The results indicated that the combined effect of these essential oils with sodium benzoate could reduce the use of sodium benzoate as an antimicrobial agent, which could decrease its possible side effects. Thus, for more significant effects, these essential oils could be combined with other agents for the preservation of drug and food products.