Antioxidant, antimicrobial, and cytotoxicity properties of chitosan-PVA film functionalised with chitooligosaccharide and gallic acid for shelf-life extension of perishable foods

Abstract

Environment-friendly, non-toxic, and functional packaging films are gaining interest worldwide for extending the shelf-life of perishable food items. Hence, this study explored the antioxidant, antimicrobial, and cytotoxicity patterns of earlier fabricated chitosan films containing polyvinyl alcohol (PVA), chitooligosaccharide (COS), and gallic acid (GA). In addition, the active properties of chitosan films were reconfirmed using tomatoes, green grapes, and pearl fish fillets as model perishable food products. Chitosan films containing COS and GA demonstrated strong DPPH (99.48 ± 0.24%) and ABTS (98.06 ± 0.91%) radicals scavenging capacity and robust potentiality in ferric reducing activity (230.93 ± 1.42, equivalent μM Fe2+/g sample). Additionally, the inhibitory rates of the fabricated films towards Escherichia coli, Listeria innocua, and Saccharomyces cerevisiae were 59.49 ± 9.17%, 79.29 ± 0.94%, and 79.55 ± 8.45%, respectively. Further, MTT assay exhibited that chitosan films were biocompatible with viability greater than 90% on HaCaT cells and 75% on Caco-2 cells. The fabricated films demonstrated non-cytotoxicity in vitro and show potential suitability for packaging applications. Moreover, the application of chitosan films on tomatoes and green grapes showed the lowest weight loss compared to the control film at room temperature (23°C) for up to 7 and 9 days, respectively. Additionally, these films also led to a reduction in total volatile basic nitrogen (TVBN) levels in the preservation of pearl fish fillets, indicating the potential for shelf-life extension.