Abstract / Summary
Abstract This study explores the sustainable valorization of Vaccinium corymbosum L. (blueberry) leaf waste as a potent bio-reductant and stabilizing agent for the phyto-mediated synthesis of silver nanoparticles (AgNPs). The phytochemical profiling of the leaf extract confirmed a terpene- and phenolic-rich composition, facilitating the biogenic reduction of Ag + ions. Successful formation of AgNPs was validated by UV–Vis spectroscopy, exhibiting a characteristic surface plasmon resonance (SPR) peak at 420–430 nm. Electron microscopy (SEM and TEM) revealed predominantly spherical nanostructures with a narrow size distribution (10–35 nm), while XRD analysis confirmed a high-purity face-centered cubic (FCC) crystalline lattice. FT-IR spectra highlighted the pivotal role of hydroxyl, carbonyl, and C–O functional groups in the capping and stabilization process. The synthesized AgNPs exhibited significant broad-spectrum antimicrobial activity, with enhanced efficacy against Gram-positive pathogens. Mechanistic evaluations via growth kinetics demonstrated that the antibacterial action is driven by membrane disruption, intracellular leakage, and oxidative stress. Furthermore, the NPs displayed dose-dependent antibiofilm activity, complemented by the intrinsic antioxidant capacity of the leaf extract. These findings demonstrate that V. corymbosum leaf waste can be effectively transformed into high-value biofunctional nanomaterials. This eco-friendly and low-energy synthesis route aligns with circular economy principles and provides a promising platform for sustainable applications in food safety and nanobiotechnology.