Alginate and fucoidan are unique polysaccharides present in brown algae and widely used in food and
medical technologies. Alginate and fucoidan were sequentially extracted from Sargassum latifolium and
used for the preparation of alginate and alginate-fucoidan blend films with or without Ca-crosslinking.
The incorporation of fucoidan and Ca2þ decreased water solubility, but increased film thickness, water
vapor permeability and oxygen permeability. The films showed good properties against ultraviolet light,
however, incorporation of fucoidan and/or Ca2þ decreased the color parameter L* value and increased the
a* and b* values of the films. The interaction of Ca2þ and fucoidan with alginate was 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. Ca2þ crosslinking decreased initial
moisture sorption and increased the maximum sorption capacity of the films. Additionally, the water
vapor diffusion and polyphenol release were expressed in terms of effective diffusion coefficient based
on simplified Fick's law. The developed films showed 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 antioxidant
activity of the films.