antioxidant activity of a number of polyphenol compoundswas reduced
due to the formation of polyphenol-milk protein complexes (Xiao et al.,
2011; Lorenz et al., 2007). Furthermore, heat denatured proteins, such
as those found in yogurt, are more likely to form polyphenol-milk protein
complexes due to the increased exposure of polyphenol binding
sites (Siebert, Troukhanova, & Lynn, 1996). This may explain the lack
of cellular antioxidant activity by the undigested yogurt samples. The
lack of cellular antioxidant activity in digested yogurt samples may be
due to pH-mediatedmodification of compounds present in the seaweed
extracts.