Polysaccharides and methods for production thereof

摘要

Gentiobiose and D-glucose are obtained by treating a 1% aqueous solution of scleroglucan (a 1,3-beta-linked polyglucose having 1,6-beta-linked glucose units with beta 1,3-D-glucanase. Acid hydrolysis of polyglucoses is also referred to.ALSO:A water-soluble polysaccharide has the structure wherein X1, X2 and X3 are hydrogen or substituted glucopyranose units having the structure and Y is OH, OR, OOCR, OCH2COOH, OSO3M, ONO2, OCS2M or OOCNH#j, where R is an aryl group or an alkyl group having 1 to 8 carbon atoms, and M is hydrogen or a cation, and wherein at least one of X1, X2 and X3 is other than hydrogen. The polysaccharide consists of a 1,3-beta-linked D-glucose polymer bearing 1,6-beta-linked D-glucose units. The polysaccharide is made by inoculating an aqueous solution containing a carbohydrate source with a micro-organism and fermenting the inoculated solution, preferably in presence of yeast extract or a mineral salt. The micro-organism may be Schlerotium glucanicum (NRRL 3006) or other species of Sclerotium, Corticium, Stromatinia and Sclerotinia. The polysaccharide may be isolated by precipitation with organic solvent, and is designated scleroglucan when produced by Sclerotium glucanicum. Scleroglucan forms aqueous gels, the viscosity of which is stable at varying pH. Examples describe the preparation of Scleroglucan xanthate, scleroglucan methyl, carboxymethyl and benzyl ethers and scleroglucan acetate, benzoate, sulphate and carbanilate.ALSO:A standard chiffon cake formulation, and a standard marsh-mallow-like cake frosting formulation contain the polysaccharide scleroglucan (a 1, 3-beta-linked polyglucose having 1, 6-beta-linked glucose units). The additive improves the texture, moisture-retaining qualities and keeping qualities of the formulation.ALSO:An aqueous solution of the polysaccharide silero-glucose (1,3-beta-linked polyglucose with 1,6-beta linked glucose units) (see Division C3) is filtered through a filter paper supported in a Buchner funnel. A smooth, glossy flexible coating is formed on the paper, which is thereby provided with a durable surface suitable for printing or writing.