Green Synthesis of Silver Nanoparticles using Punica granatum Leaf Extract: A Novel Approach to Combat Quinolone-Resistant Urinary Tract Infective Pathogens.

INTRODUCTION

Nanoparticles obtained through green synthesis play remarkable roles in biomedical applications. Urinary tract infections (UTIs) are a nightmare for the mass population, especially for women, and quinolone-resistant UTI bacteria worsen the situation. Our current investigation aimed to control quinolone-resistant pathogenic UTI bacteria with green-synthesized silver nanoparticles (AgNPs).

METHODS

Visual observation of color change, UV-Vis spectroscopic analysis, FTIR (Fourier Transform Infrared Spectroscopy), DLS (Dynamic Light Scattering), XRD (X-ray Diffraction), and TEM (Transmission Electron Microscopy) techniques were used to effectively characterize the biosynthesized AgNPs. Klebsiella variicola, Pseudomonas sp., and Staphylococcus epidermidis bacteria were isolated and identified using biochemical and molecular identification techniques from urine samples of hospitalized patients with UTI. These bacteria showed quinolone resistance to up to fourth-generation antibiotics.

RESULTS AND DISCUSSION: The results elucidated the synthesis of spherical-shaped nanosilvers coated with Punica granatum polyphenols. These biosynthesized AgNPs showed moderate polydispersity and narrow distribution. The antibacterial efficiency of the AgNPs was determined against isolated bacterial strains. Klebsiella variicola and Staphylococcus epidermidis exhibited the highest sensitivity to the nanoparticles. Nanoparticles at a concentration of 128 μg/ml inhibited bacterial growth to a great extent and gave a maximum inhibition zone of 14.67 ± 0.577 mm in diameter for both bacterial strains. In addition, toxicity analysis of synthesized nanoparticles via brine shrimp lethality assay (BSLA) showed a very low cytotoxicity level (2398.83 μg/ml), depicting safety for human use.

CONCLUSION

We can conclude that Punica granatum leaf-synthesized AgNPs could possess significant biomedical applications as potential antibacterial agents due to their bactericidal activity and low cytotoxicity.