title: Structural analysis of immunostimulating sulfated polysaccharides from Ulva pertusa.
abstract: Sulfated polysaccharides were extracted from Ulva pertusa and fractionated to obtain the most immunostimulating fraction (F(2)). The glycosidic linkages of the polysaccharides in the fraction F(2) were determined using GC-MS and 2D-NMR spectroscopy after chemical modifications, including reduction and desulfation under various conditions. Methanol was used as a sulfate acceptor for the removal of sulfates from the polysaccharides. When desulfation was carried out at 120°C, the sulfates were removed upto 90.1% from the F(2) fraction without considerable backbone degradation. The GC-MS analysis as well as NMR spectra revealed that the backbone of the polysaccharides was mainly composed of α-(1→4)-L-rhamnopyranosyl, β-(1→4)-D-glucuronosyl, β-(1→2)-L-rhamnopyranosyl, and β-(1→4)-D-xylopyranosyl residues with branches at O-2 position of rhamnose. The sulfate groups were mostly found on glucuronic acid at O-3 position.
authors.affiliation: Department of Marine Food Science and Technology, Gangneung-Wonju National University, 120 Gangneung Daehangno, Gangneung, Gangwon 210-702, South Korea.
authors.forename: Mehdi
authors.initials: M
authors.lastname: Tabarsa
authors.forename: Sung-Joon
authors.initials: SJ
authors.lastname: Lee
authors.forename: SangGuan
authors.initials: S
authors.lastname: You
mesh_terms: D002236:Carbohydrate Conformation; D007114:Immunization; D011134:Polysaccharides / Q000737:chemistry* / Q000302:isolation & purification; D013431:Sulfates / Q000737:chemistry* / Q000302:isolation & purification; D044445:Ulva / Q000737:chemistry*
chemical_list: D011134:Polysaccharides; D013431:Sulfates