Novel 2,3-Dialdehyde Cellulose-Based Films with Photodynamic Inactivation Potency by Incorporating the...

Antibacterial packaging film mediated by photodynamic inactivation (PDI) is a new concept in food industry. The objective of this study was to fabricate a green 2,3-dialdehyde cellulose (DAC)-based antimicrobial film with PDI potency by incorporating the β-cyclodextrin/curcumin (β-CD/Cur) complex as a photosensitizer. The PDI-mediated films were characterized by evaluating the surface morphology, chemical structure, light transmittance, mechanical properties, photochemical and thermal stability, and water solubility. The results showed that the DAC-CD/Cur films were soluble in water and mechanically strong with a tensile strength of 63.87 MPa and an elongation break of 1.32%, which was attributed to the formation of hydrogen bonds between DAC and β-CD/Cur molecules. Meanwhile, the composite films possessed a good light transmittance but impeded the penetration of ultraviolet light and efficiently delayed the degradation of curcumin. More importantly, the PDI-mediated films exhibited a broad-spectrum ability to kill Listeria monocytogenes, Vibrio parahaemolyticus, and Shewanella putrefaciens in pure culture. Notably, they also potently inactivated these harmful bacteria on ready-to-eat salmon with a maximum of ∼4 Log CFU/g (99.99%) reduction after 60 min irradiation (13.68 J/cm²). Therefore, the PDI-mediated DAC-CD/Cur films are novel and promising antimicrobial food packaging films in food industry.