Chemical composition and antibacterial properties of Zataria multiflora Bioss and Mentha longifolia essential oils in combination with nisin and acid acetic

Abstract

This study was conducted to determine the chemical composition of the Zataria multiflora Bioss and Mentha longifolia essential oils (ZEO and MEO) and evaluate their antibacterial efficiency, alone and in combination with nisin and acid acetic, against Escherichia coli O157: H7 and Staphylococcus aureus. The results of antimicrobial tests showed that plant EOs, nisin, and acetic acid have good bacteriostatic and bactericidal properties. In the checkerboard test, nisin had synergistic interaction with both ZEO and MEO against S. aureus and E. coli (FIC index <0.5). Also, there was a synergistic interaction between ZEO and MEO. Based on the GC-MS analysis, the main constituents of ZEO were carvacrol (49.61%), thymol (14.31%), and p-cymene (5.23%). Besides 1,8-cineole (18.46%), pulegone (14.82%), and piperitone (12.12%) were the most detected substance of MEO. The combination of nisin with the EOs can exert an inhibitory effect on bacterial growth in food. Novelty impact statement In this present study, the synergistic effect of the Zataria multiflora Bioss and Mentha longifolia essential oils (EOs) in combination with nisin and acetic acid was investigated for the first time. The interaction of EOs with nisin and acetic acid against Escherichia coli O157: H7 and Staphylococcus aureus was synergistic and additive, respectively. The two studied EOs also had a synergistic interaction in the combined use.