Green Synthesis and Characterization of Silver Nanoparticles Using Pleurotus eous and Their Antioxidant and
Mohammed Al Qutaibi1, Suresh R Kagne2
1Department of Medical Microbiology, Ibb University, Ibb, Yemen, ibb-univ.net.
Abstract:
Pleurotus eous (P. eous) contains a range of bioactive metabolites with reported antimicrobial and antioxidant potential. This work describes the green synthesis of silver nanoparticles using an aqueous extract of P. eous and evaluates their physicochemical features and in vitro antimicrobial activity. Silver nanoparticles were formed through fungal extract-mediated reduction of silver nitrate, with UV-visible spectroscopy showing a surface plasmon resonance band around 420 nm. FTIR analysis indicated the involvement of fungal biomolecules in reduction and stabilization, while XRD confirmed the crystalline, face-centered cubic structure of metallic silver. FE-SEM imaging revealed predominantly spherical nanoparticles with an average size of 39 ± 7.6 nm. The methanolic extract of P. eous showed strong antioxidant activity, with DPPH radical scavenging reaching 97.39%, and contained measurable phenolic content (1.02 ± 0.07 mg GAE g-1 dry weight), as supported by GC-MS profiling. Antimicrobial testing demonstrated that the biosynthesized silver nanoparticles exhibited moderate inhibitory effects against Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Candida albicans, Candida tropicalis, and Aspergillus niger, with inhibition zones of 11.8-16.3 mm for bacteria and 13.3-14.3 mm for fungi at 250 μg. While less potent than conventional antimicrobials, these nanoparticles demonstrated measurable activity, warranting detailed toxicity and in vivo evaluation.
