Green synthesis of silver nanoparticles using <i>Citrullus colocynthis</i> fruit: phytochemical analysis, antioxidant, and urease, carbonic anhydrase, and xanthine oxidase inhibition activities

This study aimed to investigate the phytochemical composition, antioxidant activity, and enzyme inhibition profile of <i>Citrullus colocynthis</i> and its synthesised silver nanoparticles (AgNPs). Silver nanoparticles (AgNPs) were synthesised using <i>C. colocynthis</i> fruit extract and characterised using various techniques, including UV-Visible Spectroscopy, SEM, XRD, and FTIR, which confirmed the successful formation of AgNPs. The AgNPs exhibited significant antioxidant activity, with IC₅₀ values of 0.45 ± 0.4 µg/mL, 0.45 ± 0.5 µg/mL, and 0.45 ± 0.1 µg/mL for DPPH, FICA, and HRSC assays, respectively. The nanoparticles also showed potent enzyme inhibition activity against urease, carbonic anhydrase, and xanthine oxidase, with IC₅₀ values of 90 ± 0.1 μg/mL, 221 ± 0.4 µg/mL, and 187 ± 0.9 µg/mL, respectively. Notably, the AgNPs demonstrated enhanced bioactivity compared to the plant extract, highlighting their potential as therapeutic agents. This study provides new insights into the antioxidant and enzyme inhibition potential of <i>C. colocynthis</i> AgNPs, warranting further investigation into their therapeutic applications.