Guar bean galactomannan

GUAR BEAN, Cyamopsidis semen The drug contains galactomannan with properties similar to Konjac root. 

Poly(vinyl alcohol) and lignocellulosics Carboxymethylcellulose Hydrolysed starch-g-polyacrylonitrile Galactomannan (Guar bean)... 

Guar gum is a galactomannan used like locust bean gum and at approximately the same levels. However, unlike locust bean gum, it swells in cold solution and requires no heat for complete hydration. It also induces mix separation which may be controlled with carrageenin. It is well suited for use in HTST systems. 

A review of uses of galactomannan thickening agents, of which some 23 000 tons were used worldwide in 1986, is available [354]. The use of borate ions to crosslink locust bean or guar mannose chains has been mentioned already. It has been shown that addition of borax... 

X-Ray diffraction patterns for the galactomannans from guar, locust-bean, and tara gums show, with relative humidity, continuous variation of only the a dimension of the base plane. For guar gum, the a axis varies from 1.35 nm at 0% r.h. to 3.32 nm at 78% r.h., whereas, for lo-... 

The general chemistry of the galactomannans has been reviewed by Whistler and Smart" and others,7 " and papers frequently appear that discuss the uses of guar and locust-bean gums in various industrial applications, such as in cosmetics9 and food.10,11 Most of this article deals with investigations of the structural chemistry of galac-... 

A method for purifying certain neutral polysaccharides by precipitation in borate buffer with cetyltrimethylammonium bromide was developed by Stacey and coworkers,118 but it does not appear to have been used for the isolation of galactomannan gums. It has, however, been claimed119 that guar gum and locust-bean gum can be separated by carefully controlled precipitation of the cetylpyridinium bromide complexes by 0.1 M sodium hydroxide. Guar gum is precipitated between pH 7.0 and 8.3, and locust-bean gum between 8.6 and 9.3. 

A number of problems arise in connection with the measurement of molecular weights of galactomannans. Firstly, it is very difficult to obtain true solutions of many of the gums, especially of locust-bean gum and guar gum consequently, the solutions must be filtered or centrifuged to remove undissolved or partially hydrated gum. This immediately raises the problem of fractionation of the sample, as the... 

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