Chitosan-Based Functional Films Integrated with Magnolol: Characterization, Antioxidant and Antimicrobial Activity...

The aims of this study were to develop the magnolol-chitosan films and study the positive effect of the combination of magnolol and chitosan. The addition of magnolol made the magnolol-chitosan films exhibit higher density (1.06-1.87 g/cm³), but the relatively lower water vapor permeability (12.06-7.36 × 10^-11·g·m^-1·s^-1·Pa^-1) and water content (16.10-10.64%). The dense and smooth surface and cross-section of magnolol-chitosan films were observed by environmental scanning electron microscopy (ESEM) images. The interaction of magnolol and chitosan was observed by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and thermogravimetric analysis (TGA). After the addition of magnolol, the antioxidant capacity of magnolol-chitosan films was increased from 18.99 to 82.00%, the growth of P. aeruginosa was inhibited and the inhibition percentage of biofilm formation was increased from 30.89 to 86.04%. We further verified that the application of magnolol-chitosan films on chilled pork significantly reduced the increases in pH value, inhibited the growth of microorganisms and extended the shelf life. Results suggest that magnolol had a positive effect on magnolol-chitosan films and could be effectively applied to pork preservation.