Al2O3 NPs were charac-terized by scanning electron microscopy, high-resolution transmission electron microscopy, and X-ray diffraction. The MIC was found to be in the range of 1,700–3,400 l g/ml. Almost no growth was observed at 2,000
l g/ml for up to 10 h. SEM micrograph revealed that the treated cells were significantly damaged, showed indentation on cell
surface and clusters of NPs on bacterial cell wall.