Abstract
Sulfated polysaccharides extracted from Ulva pertusa (UP) and Ulva conglobata (UC) were purified on DEAE-cellulose and Sepharose 4B gel columns. Both polymers were confirmed to be homogeneous by gel-filtration chromatography and ultracentrifugation. They were composed of rhamnose, xylose, glucuronic acid, glucose, galactose and sulfate. UP contained a high level of glucuronic acid (27%) and UC, a low level (6%), and galactose was not detected in UP. A sedimentation equilibrium measurement showed distinctly different molecular weights: 9.1×104 for UP and 8.2×105 for UC, and these results were in good agreement with values estimated by gel chromatography. Specific optical rotations for UP and UC also differed at, [α]20D=-77.8° and -26.3°, respectively. In spite of these differences, the two polymers showed similar physicochemical behavior and had similar random coil conformation in acidic buffer solutions.
