Gums of Combretaceae Myrtiflorae Genera

The most extensively studied exudate gum from this plant family is that from Anogeissus latifolia which is known as gum ghatti or Indian gum (Chap. 10.2.6). This polysaccharide has a main chain of alternating )8-D-glucopyranosyluronic acid units substituted at 0-4 and D-mannopyranosyl units substituted at 0-2 (30, 162). The D-mannopyranosyl units constitute double branch points. The side chains contain L-arabinopyranosyl, L-arabinofuranosyl, D-galactopyranosyl, and D-glucopyranosyluronic acid units. 

The gum from Anogeissus leiocarpus has been fractionated into two components the more abundant of these has been studied and shown to be similar in structure (but not identical) to the A. latifolia gum polysaccharide (30, 33, 34, 43, 162). 

All exudate gums examined from Combretum species contain D-glucopyrano-syluronic acid, 4-O-methyl-D-glucopyranosyluronic acid, D-galactopyranosyl- 

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