Zinc oxide nanoparticle: An effective antibacterial agent against pathogenic bacterial isolates

Abstract

Background: Zinc oxide nanoparticle (ZnO NP) was investigated to find out the next generation nano antibiotics that can be developed from them to counter pathogenic microorganisms responsible for multi-drug resistance. It has been seen that they have unique physicochemical properties that can be utilized against toxicological and biological properties of microorganisms. Methods: Application of well diffusion and the procedure of micro broth dilution utilizing Alamar blue were done to evaluate the inhibition zone, minimum bactericidal concentration (MBC), and the minimum inhibitory concentration (MIC). Also, the antibacterial effectiveness of ZnO NP that constitutes the genesis of biofilms was analyzed by crystal violet formation assay. Inhibition of bacteria was ascertained through the percentage of inhibition of bacterial colonies upon treating with ZnO NP. Results: In this study, we scrutinized the efficacy of ZnO NP on Gram-negative as well as Gram positive infectious strains. Ultimate inferences demonstrated the consequences that ZnO NP possessed statistically significant antibacterial efficacy with the significant inhibitory zone (16–21 mm), minimum inhibitory concentration (15.625–125 μg/ml) and minimum bactericidal concentration (62.5–250 μg/ml). Quantitative estimation of biofilms formed by Streptococcus pyogenes, Salmonella and Klebsiella pneumoniae at MIC × 2 of ZnO NP showed 2.3, 2.83 and 2.72-fold decrease, respectively. Conclusions: The results imply that ZnO NP can be utilized as substitute antibacterial agents especially against Gram positive bacterial isolates, which can help develop various antibiotic agents in the clinical setup.

Keywords

• Zinc oxide nanoparticles
• Antibacterial
• Biofilm
• Gram-positive bacteria
• Gram-negative bacteria