Development of pH and enzyme dual responsive chitosan/polyaspartic acid nanoparticle-embedded nanofibers for fruit preservation

This study focuses on the development and application of tea polyphenol-loaded chitosan/polyaspartic acid nanoparticles (TP@CS/PASP-Nps) embedded within polyvinyl alcohol (PVA) nanofibers to extend the shelf life of fruit. The nanofibers were fabricated using electrospinning, which enhanced the stability and uniform dispersion of the nanoparticles. Experimental results demonstrated that the TP@CS/PASP nanoparticles exhibit significant pH and protease-responsive release of TP, with a cumulative release of 56.22 % at pH 5.0 after 120 h, compared to 26.70 % at pH 7.0. In the presence of 1 mg/mL protease, the release of TP increased by 25.31 %. Furthermore, the nanofibers displayed excellent antimicrobial properties, inhibiting the growth of Escherichia coli, Staphylococcus aureus, and Botrytis cinerea, and exhibited antioxidant activity with a DPPH scavenging rate of 43.1 % at 10 mg/mL. When applied to strawberries, the nanofibers significantly prolonged shelf life, maintaining a 0 % mold growth rate over six days compared to 100 % in the control group. This innovative packaging system presents a promising solution for the intelligent control of active substance release, offering valuable insights into the application of stimulus-responsive nanoparticles in food preservation.