In-vitro Antimicrobial Activity of ZnO Nanoparticles Produced by Hydrothermal Method Against Some Foodborne Pathogens

Zinc oxide nanoparticles (ZnO-NPs) are synthesized via a multitude of techniques, resulting in nanoparticles of varying sizes and morphologies that directly influence their antimicrobial efficacy. The objective of this study is to ascertain the particle size and morphology of ZnO-NPs synthesised via the hydrothermal method and to evaluate their in vitro antibacterial effects against Escherichia coli O157, Salmonella Typhimurium, and Listeria monocytogenes, which are important foodborne pathogens. The ZnO-NPs were examined using a scanning electron microscope (SEM). Furthermore, the minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and the diameter of inhibition zones were measured against these pathogenic bacteria. The SEM images revealed that the ZnO-NPs exhibited a uniform distribution, with particle sizes ranging between 23 and 25 nm. The MIC and MBC values against the tested strains were found to range from 20.83 to 41.67 µg/mL and between 66.67- 83.33 µg/mL, respectively. In addition, the diameter of inhibition zones were ranged from 15.16 to 16.96 mm. The findings of the study demonstrated that ZnO-NPs s synthesized via the hydrothermal method exhibited antibacterial effects against both Gram-positive and Gram-negative bacteria. In conclusion, the use of ZnO-NPs can facilitate the improvement of the microbiological quality of foods by the inhibition of foodborne patogens.