Antibacterial Efficacy of Zinc Oxide and Titanium Dioxide Nanoparticles against Escherichia coli in Minced Meat

Abstract

Antibacterial nanoparticles are a new approach to control the safety of meat and meat products. This work aimed to investigate the antibacterial effect of zinc oxide (ZnO) and titanium dioxide (TiO2) nanoparticles, alone or together, against Escherichia coli. Antibacterial activity of these nanomaterials was evaluated using the disc diffusion method. In this regard, minced meat samples were inoculated with E. coli and treated with different concentrations of two nanomaterials (approximately 20 nm), including 6 mM and 12 mM ZnO, 6 mM and 12 mM TiO2, and a combination of 6 mM ZnO and 6 mM TiO2, then stored at 4°C for 17 days. The results indicated that ZnO (12 mM) had a significant reduction effect on E. coli count in minced meat, followed by the combination of ZnO and TiO2, and 12 mM TiO2 alone. The antibacterial activity of ZnO, TiO2, and combination of ZnO and TiO2 was also examined using a transmission electron microscope and it was found that 12Mm ZnO had a higher destructive effect on bacterial cell than the mixture of ZnO + TiO2, and 12Mm TiO2 alone. The disc diffusion method showed that ZnO (12 mM) was the most effective concentration used against E. coli. It is concluded that 12 mM ZnO nanoparticles have the best antibacterial effect against E. coli in minced meat stored at 4 °C for 17 days.