Fabrication and performance study of dihydromyricetin-fortified sodium alginate/konjac glucomannan-activated cling film

Fabricated SA/KGM/DMY edible films via hydrogen-bond-mediated supramolecular assembly. • Optimized 8% DMY loading for balanced mechanical, barrier and bioactive properties. • Achieved simultaneous browning inhibition and microbial suppression in fresh-cut apples. Food packaging is crucial for freshness preservation, with edible films gaining widespread attention. This study prepared sodium alginate (SA)/konjac glucomannan (KGM) composite films containing dihydromyricetin (DMY), with 8% DMY as optimal. Fourier transform infrared (FT-IR) spectroscopy, molecular docking, and isothermal titration calorimetry (ITC) confirmed hydrogen bonding, stabilizing DMY. The film exhibited potent antioxidant activity (88.9% DPPH scavenging), antimicrobial efficacy against both Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus (92.05% and 95.20% inhibition, respectively; log₁₀ reduction >2.50 at 12% DMY loading). Fresh-cut apple trials showed it delayed quality loss, inhibited browning (lower PPO activity), and suppressed microbial proliferation (3.97 log CFU/g vs. 5.28 log CFU/g control). The key innovations are: (i) elucidating DMY stabilization in a polysaccharide matrix via hydrogen bonding through docking and ITC; (ii) integrating antioxidant, antimicrobial, and barrier functions in a single edible film; and (iii) demonstrating dual efficacy against enzymatic browning and microbial spoilage in fresh-cut produce. Download: Download high-res image (247KB) Download: Download full-size image