Oligosaccharides generated by partial hydrolysis of the borate-rhamnogalacturonan II complex from sugar beet

The borate-rhamnogalacturonan II complex (B-RG-II), isolated from sugar beet (Beta vulgaris), was partially acid-hydrolyzed. The oligosaccharides generated were characterized by glycosyl-composition and glycosyl-linkage analyses, ES-mass, and NMR spectroscopy. Two disaccharides, alpha-L-Rhap-(1-->5)-D-Kdo and alpha-L-Araf-(1-->5)-Dha, an aceric acid-containing oligosaccharide, and a 2-O-Me-Xyl-containing oligosaccharide, in addition to partially methyl-esterified alpha-(1-->4)-oligogalacturonides were characterized. The data provide additional evidence that B-RG-II isolated from different plant species have identical structures.