Integrating green synthesized lichenan-silver nanoparticles into lichenan/chitosan matrix for photo-responsive multifunctional food packaging application
Ziying Yang, Ting‐Chi Wen, Feng Peng
Abstract
To address the challenges of foodborne microbial contamination and to overcome the inherent defects of pure chitosan films, lichenan and green synthesized lichenan-silver nanoparticle (L-AgNP) were incorporated into the chitosan matrix to develop an active multifunctional food packaging film (named CS-LAg). The strong intermolecular hydrogen bonding interactions among these substrates, combined with the filling effect of L-AgNP, significantly enhanced the mechanical properties (tensile strength increased by 138.8 %) and barrier properties of the CS-LAg nanocomposite films, particularly against water vapor, oxygen, and carbon dioxide. Moreover, the addition of L-AgNP endowed the CS-LAg nanocomposite film with improved hydrophobicity, enhanced antioxidant activity (scavenging rate > 95 %), and remarkable ultraviolet shielding performance (blocking rate > 98 %), thereby retarding the oxidative browning of fresh-cut apple slices. Notably, the CS-LAg nanocomposite film exhibited excellent visible light-triggered photothermal conversion performance, which was integrated with the inherent bacterial trapping and antibacterial capacities of both CS and L-AgNP, enabling this film to achieve photothermal-assisted multichannel synergistic sterilization for both Escherichia coli and Staphylococcus aureus (sterilization rate > 99 %). Finally, the CS-LAg nanocomposite film successfully prolonged the storage time of bananas, demonstrating its favorable food preservation capacity.