4572. Guar Gum

Nomenclature

CAS number: 9000-30-0
Guar flour; gum cyamopsis; cyamopsis gum; Burtonite V-7-E; Decorpa (Norgine); Guarina (Norgine); Glucotard (Boehringer, Mann.); Guarem (Shire).

Description and references

Mol wt about 220,000. The ground endosperms of Cyamopsis tetragonolobus (L.) Taub., Leguminosae which is cultivated in India as livestock feed. The water soluble fraction (85%) of guar flour is called guaran which consists of linear chains of (1→4)-β-d-mannopyranosyl units with α-d-galactopyranosyl units attached by (1→6) linkages. Ratio of d-galactose to d-mannose is 1:2. Effect on lipid metabolism: D. J. A. Jenkins et al., Br. Med. J. 2, 1555 (1979); on glucose and lipid levels in diabetic and healthy volunteers: U. Smith, G. Holm, Atherosclerosis (Shannon, Ire.) 45, 1 (1982); on renal tumors in diabetic rats: B. C. Chin et al., Biomed. Res. 5, 273 (1984). As source of fiber in patients with non-insulin dependent diabetes: M. E. McIvor et al., Am. J. Clin. Nutr. 41, 891 (1985). Toxicology studies: S. L. Graham et al., Food Cosmet. Toxicol. 19, 287 (1981). Comprehensive monograph: F. Smith, R. Montgomery, The Chemistry of Plant Gums and Mucilages (Reinhold, New York, 1959) 627 pp. Review: Goldstein et al. in Industrial Gums, R. L. Whistler, Ed. (Academic Press, New York, 2nd ed., 1973) p 303-321. Comprehensive description: K. Yu et al., Anal. Profiles Drug Subs. Excip. 24, 243-276 (1996).

Properties

White to yellowish white, nearly odorless, free flowing powder. Dispersible in hot or cold water, forming a colloidal solution. Slightly sol in water but not in organic solvents. Water solns are tasteless, odorless, nontoxic, of a pale, translucent gray color, and neutral. Stable to heat. Has five to eight times the thickening power of starch. Water solns may be converted to a gel by small amounts of borax. Aq dispersions are neutral. Cf. “A Comparative Study of Commercially Available Guar Gums” by I. A. Schlakman, A. J. Bartilucci, Drug Stand. 25, 149-154 (1957). LD50 in male, female rats (g/kg): 7.35, 6.77 orally (Graham).

Use

In paper sizing; as a protective colloid, stabilizer, thickening and film forming agent for cheese, salad dressings, ice cream, soups; as a binding and disintegrating agent in tablet formulations; in pharmaceutical jelly formulations; in suspensions, emulsions, lotions, creams, toothpastes; in the mining industry as a flocculant, as a filtering agent; in water treatment as a coagulant aid.

Therapeutic Category

Adjunct to diet, insulin or oral hypoglycemics in control of diabetes.