Polysaccharides of yeasts

Yeast Insoluble Polysaccharide.—The skeletal polysaccharide of yeast has been shown to be a polyglucose in which the residues are joined by 1,3-glycosidic linkages.119 An indication that the molecular weight was of the order of 8,000 (36 units) was obtained from the specific viscosity, and a closed-chain type of structure for the molecule was suggested as no end-groups were found in the methylation studies. 

In certain instances, the exocellular and intracellular polysaccharides of yeasts have been used by taxonomists as an aid in classification of the parent organisms. For example, Lipomyces lipoferus may readily be distinguished from Lipomyces starkeyi by the sugars formed on partial and on complete hydrolysis of their exocellular polysaccharides (see Table VII), a differentiation that is difficult if morphological characteristics and sugar-utilization patterns are used. ... 

Extracellular polysaccharide prod, by Alcaligenes faecalis var. myxogenes, structural or reserve polysaccharide of yeasts, fungi and higher plants. Gelling agent for foods. Claimed to show anti-HIV activity by inhibiting attachment of the virus to T-cells. Insol. H2O but absorbs H2O. Suspensions heated >54° form a firm gel. Phase 1 clinical trials (1995)... 

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