Enhanced Pathogen Control Through Thymol and Carvacrol Nanoemulsions: A Microfluidization Approach

Abstract

Nanoemulsions based on bioactive compounds have a lot of potential as antibacterial agents in the food sector due to high solubility and bioavailability. Current research was designed to investigate the impacts of NE containing thymol and carvacrol on foodborne pathogens. NE were developed by emulsifying thymol and/or carvacrol with Tween 80 using microfluidization technique. The NE were characterized to determine their droplet size distribution, zeta potential, and polydispersity index, stability, viscosity, and morphology of NE by transmission electron microscopy (TEM). The antimicrobial activity of the NE was assessed against specific foodborne pathogens (Salmonella Paratyphi A, Campylobacter jejuni, Pseudomonas aeruginosa, Staphylococcus aureus, and Enterococcus faecalis), using agar well diffusion, the minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) methods. While thymol NE incorporating sunflower oil produced smaller droplet sizes, NE produced spherical droplets that were nanoscale. The NE demonstrated remarkable stability throughout a 60-day period of storage at 4 °C. Carvacrol NE demonstrated the most effective suppression against the pathogenic bacteria tested, with inhibition values greater than 30.00 mm against E. faecalis and C. jejuni. For P. aeruginosa, the MIC value of carvacrol NE was 12.5 mg/mL, while for S. Paratyphi A, E. faecalis, and C. jejuni, it was 50 mg/mL. Apart from C. jejuni and P. aeruginosa, bactericidal concentration was > 100 mg/mL for all bacteria. As a result, carvacrol NE was observed to be more effective as an antimicrobial agent for food preservation and has potential applications in various food products to improve shelf life and safety.