Sprayable bamboo cellulose-based hydrogel coating functionalized with bamboo polyphenols for postharvest preservation of bananas and green peppers

: Bamboo processing generates abundant biomass residues rich in cellulose and polyphenols, offering potential resources for sustainable active packaging. In this study, a bamboo-derived sprayable hydrogel coating, CBS-PB-G, was developed by integrating bamboo cellulose nanofibers, bamboo polyphenols, and ε-polylysine for the postharvest preservation of bananas and green peppers. The coating formed a dense and stable network with improved barrier, antioxidant, and antibacterial properties. During storage, CBS-PB-G reduced banana weight loss from 11.81% to 6.91% and inhibited enzymatic browning by lowering PPO activity from 1467.83 to 679.33 μkat/kg FW. For green peppers, CBS-PB-G reduced MDA content from 0.25 to 0.15 μmol/g after 12 days, indicating alleviated lipid peroxidation. Overall, CBS-PB-G effectively delayed postharvest deterioration by reducing water loss, enzymatic browning, and oxidative stress. This work provides a sustainable strategy for converting bamboo biomass into sprayable bioactive coatings for fresh produce preservation.