Chitosan composite packaging film loaded with luteolin-superoxide dismutase nano-micelles: Enhancing food preservation performance

Novel chitosan-based composite film with Luteolin-SOD nano-micelles via nano-encapsulation for food preservation. • This composite film outperforms conventional packaging: superior inhibition of oxidation, delays spoilage, biodegradable. • Natural-ingredient film: promising substitute for traditional packaging, meeting eco-friendly and sustainable demands. Chitosan-based films are promising alternatives to petroleum-based food packaging materials but suffer from insufficient mechanical strength, poor water resistance, and limited antioxidant capacity. To address these issues, we synthesized chitosan-based nano-polymers loaded with luteolin (Lut) and superoxide dismutase (SOD) (CLS nano-micelles). We then incorporated these nano-micelles into a chitosan-based film to produce a CLS film. The results showed that, compared with the pure chitosan film, the mechanical properties of CLS film significantly improved, with tensile strength increasing from 6.14 MPa to 37.50 MPa and elongation at break increasing from 17.4% to 34.6%. The barrier properties of the CLS film were also enhanced, as both water vapor permeability and solubility decreased. Notably, the CLS film also exhibited excellent antioxidant properties (with DPPH inhibition rates increasing from 4.4% to 48.3% and ABTS inhibition rates rising from 7.2% to 74.6%) and demonstrated potent antibacterial activity against E. coli , S. aureus , and B. subtilis . It also exhibited excellent biocompatibility and demonstrated favorable biodegradability in soil. Grape preservation assays further confirmed its efficacy in maintaining fruit freshness. These results demonstrate that integrating CLS nano-micelles into a chitosan matrix significantly improves its mechanical, barrier, antioxidant, and antibacterial properties. This makes the CLS film a promising eco-friendly alternative for sustainable food packaging applications, offering an efficient and environmentally friendly solution. Download: Download high-res image (125KB) Download: Download full-size image