Green synthesised zinc oxide nanoparticles reveal potent in vivo and in vitro antibacterial efficacy against Proteus mirabilis isolates

Currently, the spread of antimicrobial resistance dissemination is expanding at an accelerated rate. Therefore, numerous researchers have investigated alternative treatments in an effort to combat this significant issue. This study evaluated the antibacterial properties of zinc-oxide nanoparticles (ZnO NPs) synthesised by Cycas circinalis against Proteus mirabilis clinical isolates. HPLC was utilised for the identification and quantification of C. circinalis metabolites. The green synthesis of ZnO NPs has been confirmed using UV-VIS spectrophotometry. The Fourier transform infrared spectrum of metal oxide bonds has been compared to the free C. circinalis extract spectrum. The crystalline structure and elemental composition were investigated using X-ray diffraction and Energy -dispersive X-ray techniques. The morphology of nanoparticles was assessed by scanning and transmission electron microscopies, which revealed an average particle size of 26.83 & PLUSMN; 5.87 nm with spherical outlines. The dynamic light scattering technique confirms the optimum stability of ZnO NPs with a zeta potential value equal to 26.4 & PLUSMN; 0.49 mV. Using agar well diffusion and broth microdilution methods, we elucidated the antibacterial activity of ZnO NPs in vitro. MIC values for ZnO NPs ranged from 32 to 128 & mu;g/mL. In 50% of the tested isolates, the membrane integrity was compromised by ZnO nanoparticles. In addition, we assessed the in vivo antibacterial capacity of ZnO NPs by a systemic infection induction using P. mirabilis bacteria in mice. The bacterial count in the kidney tissues was determined, and a significant decrease in CFU/g tissues was observed. The survival rate was evaluated, and the ZnO NPs treated group had higher survival rates. The histopathological studies demonstrated that kidney tissues treated with ZnO NPs had normal structures and architecture. Moreover, the immunohistochemical examinations and ELISA revealed that ZnO NPs substantially decreased the proin-flammatory mediators NF-k & beta;, COX-2, TNF-& alpha;, IL-6, and IL-1 & beta; in kidney tissues. In conclusion, the results of this study suggest that ZnO NPs are effective against bacterial infections caused by P. mirabilis.

Automated summary

Currently, antimicrobial resistance is spreading at an accelerated rate, leading researchers to investigate alternative treatments. This study evaluated the antibacterial properties of zinc-oxide nanoparticles synthesized from Cycas circinalis against Proteus mirabilis clinical isolates. The nanoparticles were found to be effective in inhibiting bacterial growth in vitro and in vivo, reducing bacterial count and improving survival rates in a mouse model. The study suggests that zinc-oxide nanoparticles could be a potential solution to bacterial infections caused by Proteus mirabilis.