The antimicrobial efficacy of Mentha oil nanoemulsion on some of the food-borne pathogens

Background and Aim : Concerns about the use of some chemical preservatives and the negative reaction of consumers to the use of these substances have led to increased attention to natural preservatives, including plant essential oils as alternatives to chemical preservatives. Nanoparticles of essential oils have been proposed to eliminate the shortcomings related to the use of essential oils in food and strengthen its antimicrobial properties. This study aimed to determine the effect of nanoemulsion of peppermint essential oil on its antimicrobial properties against some pathogenic microbes of food origin.Methods : For this purpose, the essential oil of the mint plant, which was prepared by Najian Tabriz Company, was used. Thirteen samples of nanoemulsions were prepared from the purchased essential oil. Bacillus Cereus, Escherichia Coli, Salmonella Enterica and Staphylococcus Aureus were used in this study. Results : The minimum inhibitory concentration and the minimum bactericidal concentration of free and nano emulsified essential oil were evaluated by the microdilution method. Particle size and zeta potential were also evaluated by a dynamic light scattering device. Antioxidant inhibition was also measured by diphenyl hydroxy picryl-hydrazine. The minimum growth inhibitory concentrations of free essential oil against Staphylococcus Aureus, Bacillus Cereus, Escherichia Coli and Salmonella Enterica were ۳۱.۲۵, ۶۲.۵, ۲۵۰, and ۲۵۰ μg / ml, respectively, while in the case of nanoemulsion against all of the above bacteria it was ۵۰ micrograms per milliliter. The minimum bactericidal concentrations of free essential oil were ۳۱.۲۵, ۶۲.۵, ۲۵۰, and ۲۵۰, respectively, and in the case of nanoemulsion against all the above bacteria was ۵۰ μg / ml. Regarding the antioxidant inhibition of essential oil containing peppermint nanoparticles, it had poor antioxidant properties unlike essential oil without peppermint nanoparticles. In the case of the zeta potential, the particle size of the prepared compound is ۲۶۰ nm, and the single peak indicates that the particles are monodispersed. In addition, the zeta potential is -۵.۶۷ mV, which indicates the surface charge of the nanoparticles, which can be a parameter of nanoparticle stability.Conclusion : In general, it can be said that nanoparticles of peppermint essential oil by nanoemulsion method strengthens its antimicrobial properties, especially against gram-negative bacteria.

کلیدواژه ها:

Mentha ، Food-borne pathogens ، Nano ، Antimicrobial efficacy