Title : Synthesis, characterization, and antimicrobial activity of gongronema latifolium leaf extract-mediated silver nanoparticles against multi drug-resistant uropathogens
Abstract:
Urinary tract infections (UTIs) are persistent infections in humans and a common cause for antibiotic treatment. However, the misuse and overuse of antibiotics have altered pathogen susceptibility, resulting in the emergence of resistant strains. This challenge underscores the critical need for alternative antimicrobial solutions. Silver nanoparticles have emerged as a promising candidate, demonstrating significant potential in combating antibiotics-resistant pathogens. This study synthesized, characterized, and evaluated the antimicrobial activity of Gongronema latifolium (GL) leaf extract-mediated silver nanoparticles (AgNPs) against multidrug-resistant (MDR) uropathogens. Recovered stock isolates were screened for multi-drug resistance profiles using the disk diffusion method following the Clinical and Laboratory Standard Institute Guidelines. The GL aqueous leaf extracts were used to synthesize AgNPs, according to a method described by Jerushka. The formed AgNPs were characterized using ultraviolet-visible (UV-Vis) spectroscopy, Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), X-ray diffraction spectroscopy (XRD), Energy-dispersive X-ray spectroscopy, and Dynamic light scattering. The antibacterial activity of the formed AgNPs against MDR pathogens was assessed using the disc diffusion method. Acute toxicity (LD50) were evaluated using albino mice. The multiple antibiotic resistance profiles of the identified isolates ranged between 0.2 and 1.0. The color change from pale yellow to dark brown was indicative of AgNP formation. The Gongronema latifolium-silver nanoparticles (GL-AgNPs) had UV-Vis peak wavelengths 420 nm. The FTIR analysis showed that flavonoids, terpenoids, and phenols played vital roles in AgNPs biosynthesis. The SEM analysis showed magnified images of the formed AgNPs within the nanoscale range. XRD revealed that GL-AgNPs were crystalline in structure, with average sizes of 32 nm. The mean inhibition zone diameter of the GL-AgNPs against the MDR isolates at a dose of 100 µg/mL ranged from 18 mm to 21 mm. Acute toxicity (LD50) of the formed AgNPs using albino mice indicated that oral administration of formed AgNPs at a limited dose of 5000 mg/kg was non-toxic, causing no deaths of adult mice. The study underscores the potent efficacy of GL-AgNPs against urinary tract infection, demonstrating their potential as innovative agents in antimicrobial therapy. These findings pave the way for their application in novel drug delivery systems, offering a promising avenue for combating antibiotic-resistant UTIs.
