Structural Analysis of Six Novel Oligosaccharides Synthesized by Glucosyl Transfer from β‐D‐Glucose 1‐Phosphate to Raffinose and Stachyose Using Thermoanaerobacter brockii Kojibiose Phosphorylase.

Abstract

Abstract Novel oligosaccharides (one tetra-, two penta-, two hexa- and one hepta-saccharides) were synthesized by glucosyl transfer from β- d -glucose 1-phosphate (β- d -G1P) to raffinose or stachyose using Thermoanaerobacter brockii kojibiose phosphorylase. Gas liquid chromatography analysis of methyl derivatives, MALDI-TOF-MS and NMR measurements were used for structural confirmation. The 1 H and 13 C NMR signals of each saccharide were assigned using 2D-NMR including COSY, HSQC, HSQC-TOCSY, HMBC and CH 2 -selected E-HSQC techniques. These oligosaccharides were identified as 2-α- d -glucopyranosyl-raffinose, 2 G (2-α- d -glucopyranosyl) 2 -raffinose, 2 G (2-α- d -glucopyranosyl) 3 -raffinose, 2-α- d -glucopyranosyl-stachyose, 2 G (2-α- d -glucopyranosyl) 2 -stachyose and 2 G (2-α- d -glucopyranosyl) 3 -stachyose.