The Galactan Group of Polysaccharides

The formation of degraded gums by controlled, acid hydrolysis of the parent polysaccharides involves the preferential scission of L-arabinofuranosyl and L-rhamnopyranosyl linkages, and implies 

Oligosaccharides from Partial Hydrolysis of Acacia Gums 

Oligosaccharides Senegal pycnantha mearnsii arabica nubica nilotica drepanolobium 

The substituents attached to D-glucuronic acid are readily removed on mild hydrolysis with acid, and the sugar acid units are exposed as end groups in the arabinose-free, degraded gums. For gum arabic (see later), evidence has been obtained that L-rhamnopyranosyl residues are (1 - 4)-linked to D-glucuronic acid residues. 

L-Arabinose is an important constituent of all Acacia gums, and may, as in A. arabica gum,77 account for as much as 57 % of the sugar residues. The majority of the residues of this sugar are in the furanose form, and, as far as is at present known, occur only in the exterior 

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