Preparation, characterization, and application of gallic acid-mediated photodynamic chitosan-nanocellulose-based films

• Published in: International journal of biological macromolecules Vol. 277; no. Pt 1; p. 134008
• Main Authors: Lin, Kun, Zhu, Yu-zhang, Ma, Hua-wei, Wu, Jin-cheng, Kong, Chao-nan, Xiao, Yang, Liu, Hong-cun, Zhao, Li-lan, Qin, Xiao-lin, Yang, Li-fang
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.10.2024
• Subjects: Chitosan; Composite film; Gallic acid; Nanocellulose; Photodynamic inactivation (PDI); Retain freshness; Photodynamic inactivation (PDI); Composite film; Nanocellulose; Retain freshness; Chitosan; Gallic acid
• ISSN: 0141-8130; 1879-0003; 1879-0003
• DOI: 10.1016/j.ijbiomac.2024.134008

In this study, an active film composed of gallic acid (GA), chitosan (CS), and cellulose nanocrystals (CNC) was prepared using a solution casting method and synergistic photodynamic inactivation (PDI) technology. Characterization of the film showed that the CS-CNC-GA composite film had high transparency and UV-blocking ability. The addition of GA (0.2 %–1.0 %) significantly enhanced the mechanical properties, water resistance, and thermal stability of the film. The tensile strength increased up to 46.30 MPa, and the lowest water vapor permeability was 1.16 × e−12 g/(cm·s·Pa). The PDI-treated CS-CNC-GA1.0 composite film exhibited significantly enhanced antibacterial activity, with inhibition zone diameters of 31.83 mm against Staphylococcus aureus and 21.82 mm against Escherichia coli. The CS-CNC-GA composite film also showed good antioxidant activity. Additionally, the CS-CNC-GA1.0 composite film generated a large amount of singlet oxygen under UV-C light irradiation. It was found that using the CS-CNC-GA1.0 composite film for packaging and storage of oysters at 4 °C effectively delayed the increase in pH, total colony count, and lipid oxidation in oysters. In conclusion, the CS-CNC-GA composite film based on PDI technology has great potential for applications in the preservation of aquatic products. •As a photosensitizer, gallic acid possesses strong antioxidant properties.•Gallic acid enhances the mechanical properties and water resistance of the film.•UV-C light enhances the antibacterial activity of the composite film.•Photodynamic technology enhances the preservation effect of oysters.