Antibacterial and antioxidant activities of sodium starch octenylsuccinate-based Pickering emulsion films incorporated with cinnamon essential oil

This study aimed to determine the potential of sodium starch octenylsuccinate (SSOS)-based Pickering emulsions incorporated with cinnamon essential oil (CEO) as a vehicle for delivering active biodegradable films to improve their antimicrobial and antioxidant activites. This study explored the combined effects of mixed oils (CEO and corn oils). Particle size distribution, mean drop size, ζ-potential, polymer dispersity index (PDI), and microstructure were determined to confirm emulsion stability. Well-distributed emulsion droplets maintained under a good condition and encapsulated by SSOS resulted in homogeneous and stable emulsions. The obtained mixed oil-loaded Pickering emulsions were incorporated into the SSOS film preparation, and the morphological, physical, and functional characteristics of the active film were studied. An optimal CEO/corn oil ratio decreased tensile strength but improved elongation at break, water vapor permeability, and oxygen permeability. Fourier transform infrared spectroscopy and scanning electron microscopy showed that the SSOS membrane matrix is compatible with Pickering emulsions incorporated with mixed oil. Moreover, a significant decrease was observed in loss of CEO by the Pickering emulsion method. This method exhibited antioxidant and antimicrobial activity against Escherichia coli, Staphylococcus aureus, and Bacillus subtilis, indicating that the encapsulation strategy was efficient to protect against loss of CEO during drying and storage.

Keywords: Active film; Cinnamon essential oil; Pickering emulsion.