Photo-Cross-Linked Nanofibers Containing Melissa Officinalis Extract as a Novel Active Food Packaging: An Eco-Friendly Alternative for Plastic Packaging

Food packaging plays a critical role in maintaining the freshness and quality of foods by minimizing oxidation and microbial contamination. Active packaging systems based on biodegradable polymers with green production have received great attention. Here, Melissa officinalis extract (ME) with antimicrobial and antioxidant properties was incorporated into chitosan (Cs)/ polyethylene oxide (PEO) electrospun nanofibers. Nanofibers were fabricated through electrospinning as an efficient and versatile technique with an applied voltage of 18 kV and a tip-to-collector distance of 18 cm. The total phenolic and flavonoid content of ME was measured. By incorporating ME into the nanofibers, the need for synthetic additives or preservatives can be reduced, promoting eco-friendly packaging solutions. The nanofibers were characterized regarding morphology, water contact angle, swelling degree, weight loss, mechanical strength, and vapor permeability. To improve the mechanical properties of nanofibers, photo-cross-linking was applied with benzophenone. Nanofibers were evaluated in terms of antioxidant and antifungal activities as well as their ability to protect edible mushroom quality. ME contained a significant amount of phenolic compounds as well as 1.3 mg caffeic acid/g herbal extract. Cs/PEO/ME nanofibers showed uniform and bead-free structures with an average fiber diameter of 157.7 nm. Photo-cross-linked nanofibers exhibited higher water resistance and mechanical properties compared with the as-spun formulation. ME-loaded nanofibers had higher antioxidant and antifungal activities than the empty formulation. Cross-linked Cs/PEO/ME nanofibers prolonged the shelf life of mushrooms compared to empty mats and plastic films. In conclusion, the multifunctional cross-linked Cs/PEO/ME nanofibers have broad prospects in active food packaging applications. [GRAPHICS]