Preparation and characterization of O/W nanoemulsion with Mint essential oil and Parsley aqueous extract and the presence effect of chitosan

ABSTRACT Objective(s): The oil-in-water (O/W) nanoemulsion is expanded in biomedical application due to their special properties. Mint and Parsley are known herbs with many health benefits. Chitosan (Ch) is a low toxic, biodegradable, biocompatible and safe polymer with the antibacterial activity which is used in production of nanomaterial. The aim of this study was to evaluate the nanoemulsion to achieve good antibacterial activity and suitable stability with low cytotoxicity. Methods: In the presence study, the O/W nanoemulsion was prepared by Mint essential oil in the presence of Parsley aqueous extract and chitosan aqueous solution using Span 80 and Tween 80 surfactants and high-intensity homogenizer at room temperature for 30 min. The result samples were characterized by scanning electron microscopy (SEM) and dynamic light scattering (DLS). The stability of nanoemulsion was evaluated for 50 days at different temperatures for optimized samples. The antibacterial activity of samples was measured against an important pathogen bacterium, Escherichia coli (E. coli) using inhibition zone diameter. The rheological properties of nanoemulsion were determined by presentation of viscosity at room temperature. The cytotoxicity of samples was investigated by MTT assay for HEK239 human cell line at three different concentrations for three periods of time. Results: Our results showed the nanoemulsion with nanometer size. The presence of chitosan was caused more particles with the smaller size. The low temperature was needed to protection of nanoemulsion stability and prevention of particle growth. Conclusions: Our study indicated that the nanoemulsion improved its antibacterial activity with low cytotoxicity and suitable stability.