Development of Water-Triggered Chitosan Film Containing Glucamylase for Sustained Release of Resveratrol

There is a paradox when incorporating enzyme into an edible chitosan film that chitosan is dissolved in acid solution and enzyme activity is maintained under mild conditions. A method for maintaining the pH of the chitosan solution at 4–6 to prepare a chitosan film containing β-cyclodextrin, resveratrol−β-cyclodextrin inclusion (RCI), was developed, using glucamylase and acetic acid. A considerable amount of resveratrol was released by the glucamylase-incorporated film within 15 days, and the maximum amount released was 46% of the total resveratrol content. The highest resveratrol release ratio (released resveratrol/total resveratrol) was obtained in the film with 6 mL of RCI. Scratches and spores were generated on the surface of the glucamylase-added film immersed in water (GAFW) for 7 days because of β-cyclodextrin hydrolysis during film drying and water immersion. RCI and β-cyclodextrin were extruded from the film surface and formed teardrops, which were erased by water on the GAFW surface but appeared...