Identification of Blue Pigment Formed in a D-Xylose-Glycine Reaction System

Abstract

D-Xylose (1 M), glycine (0.1 M), and sodium hydrogencarbonate (0.1 M) were dissolved in aqueous 60% ethanol at pH 8.1 and left at 26.5°C for 2 days in a dark room under nitrogen displacement. Blue pigment was isolated and purified from the blue solution by anionic exchange and gel filtration chromatographies. Blue pigment which was designated Blue-M1 (blue Maillard reaction intermediate-1) was identified as 5-{[1,4-(dicarboxymethyl)-5-(2,3-dihydroxypropyl)-2-pyrrolo[3,2-b]pyrrolyl]methine}-1,4-(dicarboxymethyl)-2-(1,2,3-trihydroxypropyl)-pyrrolo[3,2-b]pyrroly-lium. Blue-M1 is supposed to be a dimer of yellow colored pyrrolopyrrole-2-carboxaldehyde compounds. Blue-M1 that reacts readily to yellow compounds has a polymerizing activity, suggesting it is an important Maillard reaction intermediate through the formation of melanoidins.

Protective Effect of Blue-M1 against Oxidative Stress on COS-1 Cells

“…1) Miura and Gomyo, 2) and Gomyo et al, 3) have found the formation of blue pigments in the Maillard reaction of D-xylose and glycine under anaerobic conditions. Hayase et al 4) reported that a blue pigment was isolated and identified…”

“…4) Briefly, D-xylose (1 M), glycine (0.1 M) and sodium hydrogen carbonate (0.1 M) were dissolved in 1 liter of aqueous 60% ethanol, and the solution adjusted to pH 8.1 with HCl. The reaction mixture was placed in a nitrogen atmosphere and incubated at 26.5 C for 2 days, and 2 C for 4 days in a dark place.…”

Conditions for the Formation of Dilysyl-Dipyrrolones A and B, and Novel Yellow Dipyrrolone Derivatives Formed from Xylose and Amino Acids in the Presence of Lysine

“…Although several colored reaction products of pentose [5][6][7][8][9] and its decomposed products, including furfural, [10][11][12][13] have been reported to date, far fewer data on the reaction products of pentose and furfural are available than those of hexose, especially glucose, and its decomposed products.…”

Identification of the Blue Pigment Formed in aD-Glucose-Glycine Reaction System

“…2) Miura and Gomyo 3) and Gomyo et al 4) have found the formation of colored compounds in the Maillard reaction between D-xylose and glycine. Our group [5][6][7] has reported the identification of novel blue pigments designated Blue-M1 (blue Maillard intermediate-1, Fig. 1) and Blue-M2.…”