Chitosan Nanofibers Enriched with Oleuropein via Electrospinning: Potential as Active Packaging Materials

The development of sustainable and functional food packaging materials is crucial to addressing global challenges such as environmental pollution, food waste, and the demand for eco-friendly solutions. This study explores the fabrication of oleuropein-incorporated chitosan nanofibers using the electrospinning technique. Oleuropein, a phenolic compound known for its potent antioxidant and antimicrobial properties, was integrated into chitosan-based nanofibers to enhance their functional characteristics. The structural, antioxidant, and antimicrobial properties of the nanofiber films were thoroughly evaluated. Results revealed that increasing oleuropein concentration significantly influenced the viscosity of the polymer solutions and nanofiber morphology while having negligible effects on electrical conductivity. The films exhibited enhanced total phenolic content (TPC) and antioxidant activity with higher oleuropein concentrations, with the OLE_3.75 sample achieving the highest TPC (31.66±3.29 mg GAE/g film) and strong DPPH scavenging activity (87.15±1.14%). Antimicrobial tests demonstrated selective inhibition of Staphylococcus aureus (Gram-positive bacteria), with inhibition zones of 18.50±0.15 mm and 17.50±0.25 mm for OLE_2.5 and OLE_3.75 films, respectively, while showing no activity against Escherichia coli (Gram-negative bacteria). These findings underscore the potential of oleuropein-loaded PEO/chitosan nanofiber films as innovative active packaging materials with robust antioxidant and selective antimicrobial properties. This research contributes to the advancement of multifunctional, biodegradable packaging solutions that align with sustainability and food safety goals, offering promising applications in food preservation and biomedical fields.