Polysaccharides fromSpirulina platensis

A lipoglucan and a lipopolysaccharide have been isolated from an aqueous phenol extract of the cells ofSpirulina platensis. The carbohydrate moiety of the lipopolysaccharide consists of residues of rhamnose, glucose, 2-keto-3-deoxymanno-octanic acid, and glucosamine. A 2,3-di-O-methylpentose and a 2-O-methyl-6-deoxyhexose have been detected as minor components, and the presence of galactose, mannose, and xylose residues in trace amounts is possible. The lipid component of the biopolymers includes residues of glucosamine and of fatty acids: myristic, palmitic, and stearic. The carbohydrate chain of the lipoglucan is constructed of 1,4-bound glucose residues. The side chains are attached to the main chain by 1,6-glycosidic bonds. The polysaccharide component of the liposaccharide is constructed mainly of rhamnose residues linked by 1,3- and 1,2-bonds and of glucose residues linked by 1,4-bonds.