Eco-friendly film with highly efficient sterilization for food preservation by incorporating natural products into starch/polyvinyl alcohol matrix.

An advanced biodegradable packaging film with antimicrobial and fresh-maintaining functions was constructed by incorporating berberine and L-arginine into the starch/polyvinyl alcohol (PVA) film matrix. The film was endowed with a dual antibacterial capacity thanks to the intrinsic antibacterial capability of berberine and cascaded photodynamic sterilization. The aggregated berberine presents an excellent photodynamic activity to generate reactive oxygen species (ROS), which further triggers the NO release from L-arginine. Under the synergetic action of ROS and NO, the as-prepared film not only has an antibacterial efficiency of over 99 % against both S. aureus and E. coli but also delays fruit ripening through antagonistic effects on ethylene to extend the shelf life of food. Meanwhile, the as-prepared film presents UV-shielding properties, thermal stability, and considerable mechanical properties. Specifically, the packaging film exhibits good biocompatibility and is biodegradable, with a degradation rate of 56 % within 16 days, which has great potential for improving food safety and environmental events.