Structural Studies by Stepwise Enzymatic Degradation of the Main of Soybean Soluble Polysaccharides Consisting of Galacturonan and Rhamnogalacturonan JSM Backbone

rhamnogalacturonan (RG), which were composed of the diglycosyl repeating "nit, -4)-or-D-GalpA-(1-2)-a-LRhap-(1-. The side chains of B-1,4-galactans, branched with fucose and arabinose residues, were linked to the C-4 side of rhamnose residues in the RG regions. The degree of po]ymerization (dps) of GN, which linked the RG regions together, was estimated to be about 4-10 residues, and some were modified with xylose residues on the C-3 side of the galacturonates. The dps of GN at the reducing end of SSPS was estimated to be about 7-9 residues. Moreoyer, the fragment of the basic structure of the RG region, -[4)-a-D-GalpA-(1.2)-a-L-Rhap-