Alginate and fucoidan extracted from the brown macroalga Sargassum latifolium and chitosan derived
from the filamentous fungus Aspergillus niger were used for the development of edible films with natural
antioxidant properties. The incorporation of fucoidan and/or Ca2þ into the alginate-chitosan films
decreased water solubility, but increased film thickness, water vapor permeability and oxygen permeability.
The developed films showed good barrier properties against ultraviolet light. The interactions
between film components were investigated using FTIR analysis which confirmed the presence of
hydrogen bonded interaction. Kinetics of moisture sorption and polyphenol release exhibited a good fit
to Peleg's model. Film moisture content at equilibrium was increased by fucoidan blending. Additionally,
the water vapor diffusion and polyphenol release were expressed in terms of effective diffusion coefficient
based on simplified Fick's second law. The developed films exhibited good antioxidant properties as
measured by total antioxidant assay, ferric reducing antioxidant power and hydroxyl radical scavenging
activity. Both film type and the type of the food simulant markedly affected the polyphenol release and
the subsequent antioxidant activity of the films.