Studies on Browning Reaction Products from Reducing Sugars and Amino Acids

Part XII. Changes of antioxidative activities of browning reaction products between D-xylose and L-amino acids or amines during storage

Abstract

The changes of the antioxidative activities of the browning reaction products between D-xylose and one of the followillg compounds, that is, glycine, L-histidine, L-threonine, L-valine, L-lysine, n-buthylamine, n-hexylamine and octylamine were investigated against the autoxidation of linoleic acid during the storage at 37°C in aqueous system. It was observed that the color intensity and the reducing power for potassium-ferricyanide of the browning reaction products between D-xylose and amines were greatly decreased during the storage and that the absorbance maximum of the product from D-xylose-n-butylamine in UV-spectrum shifted to shorter wave length at the same time. The antioxidative activities of these browning reaction products on linoleic acid decreased along with the storage, especially in D-xylose-n-butylamine system.
On the other hand, the changes of color intensity, the reducing power and the UV-spectrum of the browning reaction products from D-xylose-L-amino acids were less than those from D-xylose-amines and moreover their antioxidative activities did not decreased after the storage for 34 days at 37°C.