Toxicity mechanism of titanium dioxide and zinc oxide nanoparticles against food pathogens

Food preservation is an important field of research. It extends the shelf life of major food products. Our current study is based on food preservation through TiO_{2} and ZnO nanoparticles. TiO_{2} and ZnO are biocompatible nanomaterial. The biocompatibility of the materials were established through toxicity studies on cell lines. Titanium dioxide and Zinc Oxide nanoparticle were synthesized by wet chemical process. They are characterized by X-Ray diffraction and TEM. The antibacterial activities of both the materials were analysed to ensure their effectiveness as food preservative against Salmonella typhi, Klebsiella pneumoniae and Shigella flexneri. The results indicates that TiO_{2} and ZnO nanoparticle inhibits Salmonella, Klebsiella and Shigella. The mode of action is by the generation of ROS in cases of Salmonella, Klebsiella. Mode of action in Shigella is still unclear. It was also proved that TiO_{2} and ZnO nanoparticle are biocompatible materials.