Nano-curcumin Capped Au/ZnO Nanocomposite: A Promising Approach to Protect from Staphylococcus Aureus Infection through Inhibits Production of α-Hemolysin

Abstract Gold with Zinc Oxide nanoparticles (Au@ZnO NPs) were prepared by laser ablation then capped with Curcumin nanoparticles. The ability of Nano-curcumin-Au/ZnO nanocomposite as a promising antibacterial agent was tested against Staphylococcus aureus. Cur-Au@ZnO NPs were characterized by TEM, FTIR spectroscopy, and Uv-spectroum. TEM image of Au@ZnO NPs has grain size almost 27–38 nm and it increased after capped Nano-curcumin to 72–113 nm. Agar well diffusion method was used to evaluate the antibacterial activity of Cur-Au@ZnO against S.aureus. The activity of Cur-Au@ZnO NPs was determined via detection of (ROS) using (AO/EtBr) staining assay. The bacterial cytoplasmic membrane and nucleic acid were penetrated by tested nanoparticles, resulting in bacterial strain destruction. The results showed that Cur-Au@ZnO NPs as a novel DNA-mediated antibacterial agent. The Cur-Au@ZnO were observed to destroy the bacterial cells by permeating the bacterial nucleic acid and cytoplasmic membrane, resulting in the loss of cell-wall integrity, nucleic acid damage, and increased cell-wall permeability. Furthermore, in the present study we investigated the activity of Cur-Au@ZnO NPs against bacterial α-Hemolysin toxin. Western blot were used to measure the effect of Cur-Au@ZnO NPs on α-Hemolysin produced by S. aureus. The effectiveness of Cur-Au@ZnO NPs against human alveolar epithelial cell injury by α-Hemolysin was tested using live ⁄ dead staining. Also, we demonstrated the role of Cur-Au@ZnO NPs against S. aureus through histopathology examination in a mouse model. Taken together, Cur-Au@ZnO NPs is a potent inhibitor of α-hemolysin secreted by S. aureus. So, Cur-Au@ZnO NPs mediated inhibition of α-Hemolysin production may offer a new strategy in combating pathogen infections. The Cur-Au@ZnO could serve as a potential antibacterial agent in future for biomedical and pharmaceutical applications.