Composition of gum exudates from Anacardium occidentale

The composition and solution properties of Indian and Papuan specimens of the gum from Anacardium occidentale have been studied and found to be closely similar. Contrary to earlier reports by Indian workers, this gum does not contain galacturonic acid. It does, however, contain glucose; this appears to be the first report of the presence of this sugar in a plant gum exudate. A freeze-dried sample of the gum was examined at intervals over a period of 2 months; its weight-average MW increased by a factor of three in that time, and molecular-sieve chromatography showed that self-association occurred with the formation of a small proportion of a very high MW component.