Polysaccharides glycosylation

Every polysaccharide contains glycosyl units with unsubstituted hydroxyl groups available for esterification or etherification. Polysaccharide derivatives are described by their degree of substitution (DS), which is the average number of substituent groups per glycosyl unit. Because each monomeric unit of cellulose molecules has free hydroxyl groups at C-2, C-3, and C-6, the maximum DS for cellulose, and all polysaccharides composed exclusively of neutral hexosyl units, the majority of polysaccharides, is 3.0. 

Rhamnogalacturonan 11 (RG-11) is a structurally complex, pectic polysaccharide that is present in the primary cell-walls of higher plants. It is composed of 60 glycosyl residues, and is a very complex molecule indeed. For example, on acid hydrolysis, at least ten different monosaccharides are formed, including the novel aceric acid (30), which is the only branched-... 

Imidazole-HCl soluble polysaccharides Most of the polysaccharides of this group didn t elute from the Q-Sepharose column with 10 mM buffer (Table 3). The glycosyl composition (Table 4) shows that these polysaccharides are homogalacturonans and ramnogalacturonans with... 

Table 4 Glycosyl composition of Imidazole-HCl soluble polysaccharides (mol%) ...

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