HAIRY (RAMIFIED) REGIONS OF PECTINS .3. IDENTIFICATION BY NMR-SPECTROSCOPY OF OLIGOSACCHARIDES OBTAINED BY TREATMENT OF THE HAIRY REGIONS OF APPLE PECTIN WITH RHAMNOGALACTURONASE

2D-N.m.r. methods have been used to determine the composition of a mixture of oligosaccharides obtained by enzymic degradation of the modified hairy (ramified) regions of apple pectin with a new rhamnogalacturonase. The structures of the oligosaccharides were based on the unit α-Rhap-(1→4)-α-GalA-(1→2)-α-Rhap-(1→4)-GalA. A β-Galp unit was 4-linked to approximately half of the terminal Rhap residues and to half of the (1→2)-linked Rhap residues. The sample contained a mixture of a tetrasaccharide, two pentasaccharides, and one hexasaccharide. © 1990.