Abstract
A gelling polysaccharide was extracted from Ibaranori (Hypnea charoides LAMoRoux) and purified by gelation with potassium chloride. The total carbohydrate, ash and water content of the polysaccharide were 70.2, 20.4 and 3.2%, respectively. The content of total sulfate and sulfate in the ash was estimated to be 19.2 and 12.9%, respectively. Molecular mass of the polysaccharide was estimated to be about 2.3×105. The polysaccharide was composed of D-galactose, 3, 6-anhydro-D-galactose and ester sulfate in a molar ratio of 1.2 : 0.9:1.2. The infrared spectrum and values of optical rotation of the polysac charide at different temperatures were in agreement with those of κ-carrageenan . Gelation occurred at a concentration of 0.2% aqueous solution upon addition of potassium chloride (0.2%) at room temperature. These results indicate that the gelling polysaccharide is a κ-carrageenan .
