Eco-friendly optimization and green biosynthesis of Cu(II) nanocomposites from Stereum ostrea biomass extract: enhanced antibiofilm efficacy against pathogenic bacteria

This study presents an eco-friendly approach to optimizing the extraction of bioactive compounds from false turkey-tail (Stereum ostrea) mushroom biomass and their application in green synthesis of Cu(II) nanocomposites for antibiofilm applications. Key extraction parameter biomass concentration (0.15%), solvent (distilled water), time (60 min), and temperature (20 °C) were systematically varied and evaluated using UV-Vis spectroscopy to maximize yield and bioactive quality, aligning with sustainable green chemistry principles. Morphological analysis via metallurgical microscopy at 10 × and 20 × magnifications revealed structural changes in treated versus untreated biomass, while Fourier-transform infrared spectroscopy (FTIR) identified functional groups (e.g., hydroxyl and carbonyl) serving as reducing and stabilizing agents. The optimized aqueous extract facilitated room-temperature biosynthesis of Cu(II) nanoparticles, confirmed by scanning electron microscopy (SEM) for uniform morphology. Antibiofilm activity was assessed in vitro using crystal violet broth assays against Staphylococcus aureus and Escherichia coli. The extract exhibited potent inhibition (71% for S. aureus and 37% for E. coli), with nanocomposites enhancing efficacy through synergistic effects. This integrated methodology demonstrates the potential of mushroom-derived nanomaterials as biodegradable, non-toxic antimicrobial agents, promoting sustainable alternatives to conventional chemical syntheses in biomedical and environmental sectors. By minimizing energy use and hazardous solvents, this work advances green nanotechnology for biofilm-related challenges.