Beech galactan

Galactans have been obtained which contain 6-linked in addition to 4-linked galactosyl residues 94, 96, 126). In two of the cases studied, the 6-linked residues accounted for approximately 4% of the polymer and are therefore quantitatively minor components of the polysaccharide 94, 126). On the other hand, beech galactan is a polysaccharide with a major amount of 6-linked residues although the amount of the polysaccharide accounted for by the 6-linked galactosyl residues has not been determined (96). The fact that 6-linked and 4-linked galactosyl residues are present in a single polymer has been established by isolation of the trisaccharide Gal-(l- 6)-Gal-(l- 4)-Gal 96). 

Meier, H. (1962). Studies on a galactan from tension wood of beech (Fagus Silvatica L). Acta Chem. Scand. 16, 2275-2283. 

Galactans have been isolated from citrus pectin 80), from white willow 126), and from beech 96). As with the arabans, no homogalactan has ever been isolated directly from primary cell walls, although the gly-cosyl linkages which comprise those homogalactans which have been studied are also present, in similar ratios, in primary cell walls 123). 

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