Eco-friendly synthesis of zinc oxide nanoparticles using Bacillus Subtilis, characterization and antibacterial potential against Staphylococcus aureus associated with cardiac catheterization

Zinc Oxide nanoparticles (ZnONPs), which have well-known antimicrobial properties, are used extensively in various medical and general applications. In this analysis, 70-gram positive bacterial isolates were obtained from 100 patients using cardiac catheterization, with 54 Staphylococcus aureus and 16 other positive pathogenic bacteria. Accordingly, morphological, cultural and biochemical testes confirmed the results by VITEK 2 System. The synthesis of Zinc Oxide nanoparticles (ZnO NPs) was done using eco-friendly biological methods by Bacillus Subtilis filtrate which was identified and characterized by UV–Vis Spectrophotometer, SEM, AFM and FTIR, the pH value for the various of ZnONPS is about 7.1 and temperature 37 °C. Furthermore, the antibacterial efficacy of biological synthesized ZnO NPs against this isolated Staphylococcus aureus was determined. The results of SEM illustrated the morphology and sizes of ZnO NPs which are spherical and ovoid with the size range of 20-70 nm. The UV-Vis spectrum indicated the absorption bands of ZnO NPs at 378 nm. Antimicrobial susceptibility test was conducted for 54 isolates against 10 commonly-used antimicrobial agents using Kirby-Bauer disk diffusion method. The results of this study showed the highest rate of resistance against Amoxcillin/Clavulanic acid, Methicillin, tetracycline, Erythromycin and Azithromycin, and moderate resistance to Chloramphenicol. The synergistic effect of antibiotics (Amoxcillin / Clavulanic acid, Methicillin, tetracycline, Erythromycin, Azithromycin, Amikacine, penicillin G, Ampecilline, Trimethoprim\ sulphamethazole and Chloramphenicol) against Staphylococcus aureus was significantly increased in presence of ZnONPs compared to antibiotics only. Conclusion ZnO NPs demonstrate a good synergistic effect with antibiotics, which can open avenues for a future combination therapy against pathogenic bacteria.