Enhancement of Chitosan Film Properties via Hydrogen Bonding with Waste-Derived Loquat Peel Polyphenols and Its Application in Food Packaging

Chitosan (CS) films were enhanced by incorporating varying volumes of loquat peel extract (LPE) to address limitations in mechanical strength and antioxidant capacity. The CS/LPE films showed remarkable improvement in elongation at break (increasing from 12.71 to 33.12%) and barrier properties, with CS/20LPE achieving a 44.5% reduction in water vapor permeability (5.31 × 10^-11 g/(m·Pa·s)) and 77.6% lower oxygen transmission (1.04 × 10^-6 g·mm/(m²·s)). Characterization confirmed hydrogen bonding between CS and LPE components induces molecular rearrangement (XRD), denser morphology (SEM), and enhanced intermolecular interactions (FTIR/XPS). XPS analysis revealed significant linear correlations between C-OH/C-N content and mechanical properties (R² = 0.99), directly evidencing hydrogen bonding's role. HPLC-TOF-MS/MS identified 14 bioactive constituents in LPE, demonstrating 58.78% DPPH and 60.74% ABTS scavenging rates with 99% antimicrobial inhibition against E. coli/S. aureus. The films achieved complete biodegradation within 40 days and extended fresh-cut cantaloupe shelf life by 7 days, advancing sustainable packaging through agricultural waste valorization.