Poly(butylene succinate) films modified with functional deep eutectic solvent/orange peel extract systems

The development of biodegradable packaging materials with enhanced functional properties is crucial for sustainable food preservation. This work presents an investigation of poly(butylene succinate) (PBS) films modified with hydrophobic deep eutectic solvents (DESs) and orange peel (OP) extracts to enhance their antioxidant and antibacterial properties. Various PBS systems modified with mixtures based on two selected terpenes: thymol (Thy) and limonene (Lim) with lauric acid (C12): Thy:C12 and Lim:C12, without and with OP extracts, were evaluated for their physicochemical, optical, and bioactive properties. The modified films showed improved tensile strength (15.6 MPa) and elongation at break (32 %), compared to unmodified PBS (11.0 MPa and 20.5 %). Water vapor transmission rate (WVTR) was reduced, enhancing barrier properties. Antioxidant activity (DPPH inhibition) increased up to 24 % in DES-OP formulations, and antibacterial assays showed inhibition zones of 17.2 mm against Staphylococcus aureus . PBS films modified with hydrophobic DESs and OP extracts from food waste offer a sustainable alternative to conventional plastics with enhanced bioactive properties. Future studies should focus on long-term stability, biodegradation kinetics, industrial processing methods and applications to optimize their commercial viability in food industries. • PBS films were modified using hydrophobic DES and orange peel extracts. • Modified films showed improved antibacterial and antioxidant properties. • Lim:C12-based films had better mechanical and barrier properties. • Thymol-based films showed stronger antimicrobial effects, especially on S. aureus. • These films offer a sustainable option for active food packaging.