Separation of Model Melanoidin into Components with Copper Chelating Sepharose 6B Column Chromatography and Comparison of Chelating Activity.

Nondialyzable model melanoidin prepared from glucose-glycine was separated into 6 components by pHgradient elution on a copper chelated Sepharose 6B column.The separated components were measured for copper chelating activity, UV-VISspectrophotometry, and electrofocusing.The UV-VIS spectra of these componentswere found to be almost the same, but the melanoidin componentswith stronger affinity to the Cu column were found to be smaller in Kd.Their electrofocusing profiles were similar, and the electrofocused bands were categorized into four major groups with pi 2.5-4.0.Major chelating activity of the melanoidin components was due to a band of pi 2.7 on the electrofocusing.Melanoidin is a colored compound generally found in food in a minute quantity, and it is formed during food processing and preservation through amino-carbonyl reactions.The