Abstract
Antibacterial activity of MgO nanoparticles (NPs) was evaluated against the Gram-negative bacteria Escherichia coli and Pseudomonas aeruginosa as well as the Gram-positive bacterium Staphylococcus aureus by microtitre plate-based assay incorporating resazurin as an indicator of cell growth. MgO NPs exhibited antibacterial activity with minimal inhibitory concentration of 500 lg/mL against E. coli and 1,000 lg/mL for P. aeruginosa and S. aureus. MgO NPs enhanced ultrasound-induced lipid peroxidation in the liposomal membrane. It was suggested that the mechanism of the antibacterial activity of the MgO NPs relied on the presence of defects or oxygen vacancy at the surface of the nanoparticle which led to the lipid peroxidation and reactive oxygen species generation.