4416. Ghatti Gum

Nomenclature

CAS number: 9000-28-6
Gum Ghatti; Indian gum.

Description and references

The gummy exudate from stems of Anogeissus latifolia Wall., Combretaceae, abundant in India and Ceylon, cf. C. L. Mantell, The Water-Soluble Gums (New York, 1947). Name derived from the word ghats, meaning passes, and given to the gum because of its ancient mountain transportation routes. Structure is a complex water-soluble polysaccharide occurring as a calcium-magnesium salt; composed of l-arabinose, d-galactose, d-mannose, d-xylose, d-glucuronic acid, in a molar ratio of 10:6:2:1:2, and traces of 6-deoxyhexose: Aspinall et al., J. Chem. Soc. 1955, 1160. Early investigation of chemistry and mol wt: Shaw et al., Proc. S. D. Acad. Sci. 15, 46 (1935); 16, 34 (1936); 17, 27 (1937); 19, 130 (1939); 21, 78 (1941). Review: Meer et al., in Industrial Gums, R. L. Whistler, Ed. (Academic Press, New York, 2nd ed., 1973) pp 265-271.

Properties

Ghatti gum sold in the U.S. usually has been autoclaved in order to make all of the gum water-sol. The U.S. Dispensatory (24th ed.) states that gum Ghatti suitable as clinical laboratory reagent is entirely sol in 5 parts of cold water. Forms a very viscous mucilage, more viscous but less adhesive than acacia. Insol in 90% alcohol. [α]D25 +42° (dil H2SO4). Gum ghatti solns may be colored slightly due to traces of pigment remaining in the gum. Does not form a true gel.

Use

As substitute for acacia. As emulsifying agent in pharmaceuticals, oils, waxes.