Evaluation of inhibitory effect of Magnesium Oxide nanoparticles on the viability of planktonic and biofilm forms of Pseudomonas aeruginosa

Abdollah Ghasemian; sima  Shakerhagh; zahra Moradpour

doi:10.5455/EJMID.20241105085834

Abstract
The need for developing new antimicrobial approaches comes from the growing antibiotic resistance in pathogenic bacteria, which is a serious concern to public health. Metal nanoparticles have increasingly been investigated in this field owing to their multiple mechanisms of action against microbes. The object of this study was to evaluate the antimicrobial activity of Magnesium Oxide nanoparticles on Pseudomonas aeruginosa. The effect of different concentrations of nanoparticles on both planktonic and biofilm forms was assessed by recording the corresponding optical density. Spot assays showed clear plaques on the bacterial lawn in the presence and absence of Triphenyl tetrazolium chloride, an indicator dye for living microorganisms. The minimum inhibitory and minimum bactericidal concentrations for planktonic cells were found to be 1 mg/mL and 2 mg/mL, respectively. Minimum biofilm inhibitory and minimum biofilm bactericidal values were determined to be 0.8 and 1.6 mg/mL, respectively. Magnesium Oxide nanoparticles exhibited antibacterial activity in a dose-dependent manner and employing appropriate concentrations of nanoparticles resulted in at least a 95% reduction in the growth of planktonic cells and biofilm formation. The results suggest that Magnesium Oxide nanoparticles have a potent inhibitory effect against planktonic and biofilm forms of Pseudomonas aeruginosa. Due to developing resistance in Pseudomonas aeruginosa strains to current antibacterial therapies and the fact that Magnesium Oxide nanoparticle is metabolized in the body, it can possibly be a candidate for adjunctive or alternative therapies.

Key words: MgO Nanoparticle, Pseudomonas aeruginosa, Antibiotic Resistance, Antimicrobial Agent