RESUMO
Aim: The aim of the present study was to characterize the zinc oxide nano particle incorporated Chitosan (ZnO-NP-CS) and its antimicrobial activity. Methodology: Zinc oxide nanoparticles (ZnO-NP) were prepared by sol-gel method and Minimum Inhibitory Concentration (MIC), Minimum bactericidal Concentration (MBC) and agar well diffusion method was used for the assessment of antibacterial activity of ZnO-NP and ZnO-NP-CS as well. Results: In UV–spectroscopy, blue shift in wavelength (~365 nm) corresponding to bulk ZnO particles (~385 nm) indicates the nano size. In SEM image, ZnO-NP appeared as nano flake shape and ZnO-NP treated Methicillin resistant Staphylococcus aureus and Pseudomonas aeruginosa (PA) bacteria illustrates leakage of intracellular content, fusion and shrinkage of bacteria, respectively. The MIC of ZnO-NP for most of food pathogens were between 0.01 to 0.1mg. Lower MIC was observed for Vibrio cholerae and Listeria monocytogenes; higher MIC was observed for Bacillus cereus and Pseudomonas aeruginosa. In antibiogram assay, the zone of inhibition of ZnO-NP-CS was equal to commercial antibiotics against Multiple Drug Resistant bacteria. Interpretation: The combined effect of ZnO-NP and chitosan is better than the individual component, i.e., around 5–15 mm wider zone of inhibition than chitosan. ZnO-NP-CS can be a suitable alternative for the treatment of wound infected by multiple drug resistant bacteria