Comparative characterization and release study of edible films of chitosan and natural extracts

The aim of the present work is to investigate the combinative effects two natural extracts Piper betle L. (PBLE) and Sonneratia ovata (SOE) on the physico-mechanical and biological properties of chitosan films (CS) and compare the release properties of polyphenols from formulated films in different food simulants. Films containing the extracts showed better water permeation barrier, UV-protection property, antioxidant and antibacterial activities than control chitosan films. The co-addition of PBLE and SOE intermediate the mechanical behavior and thermostability as well as antioxidant and antimicrobial activities of the chitosan based blend film. Moreover, the mechanism and kinetics of polyphenol release from films in different solvents were investigated. The highest amount of polyphenols released from all chitosan blend films was observed in acidic environment due to chitosan solubility. It was also found that the release data are well-fitted with Peleg's model and the release process was controlled by quasi-Fickian diffusion mechanism.