Green Synthesis and Characterization of Silver Nanoparticles Using Lespedeza juncea Extract: An Insight Into Its Antibacterial, Antifungal, and Enzyme Inhibitory Potential

Herein, we adapted a quick, cost‐effective, and environmentally friendly biological method for the synthesis of Ag‐NPs using silver nitrate solution as a precursor, and the aqueous leaf extract of Lespedeza juncea (Chinese lespedeza) was exploited to synthesize Ag‐NPs. Various physiochemical characterization techniques were used to characterize the nanoparticles. The UV spectrum revealed a resonance absorption peak at 428 nm, indicating successful synthesis of the nanoparticles. The EDX results indicated the presence of Ag, C, O, and Cl elements in biosynthesized Ag‐NPs with elemental compositions of 53.93%, 32.34%, 12.49%, and 1.23%, respectively. The XRD analysis displayed the crystalline nature of the nanoparticles with a face‐centered cubic lattice. The FTIR spectrum confirmed the involvement of plant‐based biological compounds as reducing and capping agents. TEM revealed quasi‐spherical Ag‐NPs of 50 nm or smaller in size. An insight into its biological activities reveals significant antimicrobial activities against Staphylococcus aureus (14.1 ± 0.76 mm), Pseudomonas aeruginosa (11.50 ± 0.40 mm), Escherichia coli (16 ± 0.95 mm), and the fungal strains, viz. Candida albicans (14 ± 0.80 mm), Aspergillus flavus (16.50 ± 0.50 mm), Aspergillus niger (17 ± 0.86 mm) and afflicted 75% mortality to Caenorhabditis elegans . Furthermore, the Ag‐NPs were found to be potent inhibitors of the enzymes tyrosinase, urease, acetylcholinesterase, and butyrylcholinesterase with IC 50 values of 14.3 ± 0.2, 19.5 ± 1.1, 9.3 ± 1.3, and 32.65 ± 1.9 μg/mL, respectively. The overall outcome of the study suggests that L. juncea mediated synthesized Ag‐NPs hold the potential to be employed as a promising tool for their antibacterial, antifungal, nematocidal, and for a variety of enzymes inhibitory activities.