Spectral Analyses of Interaction between Congo Red and Cyclodextrins or Maltooligosaccharides

Abstract

We found that various kinds of hydrophobic food stuffs such as polyphenols and fatty acids were dispersed into water phase by the action of CGTase (cyclodextrin producing enzyme) on the mixture of hydrophobic food stuffs and starch, and supposed that some complex of the stuffs might be formed with cyclodextrins and maltooligosaccharides resultantly produced from starch by the action of CGTase. In the case of using α-amylase instead of CGTase, some hydrophobic food stuffs such as green tea powder was also dispersed into water phase in the same way. We named these complexes “CD wrap” and “Sugar wrap” . To make these phenomena clear by using spectrophotometry and the NMR method, we showed that maltooligosaccharides having some degree of polymerization changed the color of congo red and that the NMR profile of such maltooligosaccharides was changed by the addition of congo red. From these results, we inferred that congo red interacted with maltoheptaose mildly to form some complex.