Characterization of chitosan/eugenol-loaded IRMOF-3 nanoparticles composite films with sustained antibacterial activity and their application in postharvest preservation of strawberries

In this work, we prepared chitosan/eugenol-loaded IRMOF-3 nanoparticles (CS/IRMOF-3-EU) composite films using (0, 2, 4, and 6 wt%) isoreticular metal-organic framework (IRMOF-3) nanoparticles loaded with eugenol (IRMOF-3-EU), co-blended with chitosan to develop environmentally friendly food packaging materials with sustained antimicrobial activity. The microstructure and physicochemical properties of the composite films were investigated. The addition of IRMOF-3-EU to the CS matrix significantly enhanced the UV-blocking property and elongation at the break of the composite films; the CS/IRMOF-3-EU composite films inherited the antioxidant and antibacterial properties of eugenol (EU), and the DPPH radical scavenging ability was increased to 53.8% with the addition of 6% IRMOF-3-EU, while it showed excellent antibacterial ability; in addition, the CS/IRMOF-3-EU composite films achieved the sustainable release of eugenol to achieve the long-lasting antibacterial effect. Experiments on strawberry preservation applications showed that the CS/IRMOF-3-EU films slowed down the deterioration of strawberry quality, delayed the decline of hardness, effectively suppressed weight loss, H 2 O 2 content, and malondialdehyde content, and delayed the decline of catalase activity and peroxidase activity. It showed that the CS/IRMOF-3-EU composite films could be used to maintain the postharvest quality and prolong the shelf life of strawberries.