title: Structural characterization of polysaccharides from the roots of Urtica fissa.
abstract: Three polysaccharides were isolated from the roots of Urtica fissa by extraction, ultrafiltration, anion-exchange, and gel-filtration chromatography. The structures were characterized using acetylation, methylation, and spectral methods (GCMS, NMR). All three polysaccharides are mainly composed of D-arabinofuranosyl, D-galactopyranosyl, D-glucopyranosyl residues with different structural characteristics. Polysaccharide A of MW 5.2 x 10(3) contained a linear chain of 1-linked beta-D-glucopyranosyl, 1,6-linked beta-D-glucopyranosyl, 1,6-linked alpha-galactopyranosyl, and 1,5-linked beta-arabinofuranosyl moieties. Polysaccharide B of MW 7.7 x 10(4) possessed a chain consisting of 1,5-linked alpha-D-arabinofuranosyl, 1,3-linked beta-D-mannopyranosyl, 1,6-linked beta-D-glucopyranosyl, and 1,6-linked alpha-D-galactopyranosyl residues, but 4-O of alpha-D-galactopyranosyl residues were branched by terminal beta-D-glucopyranosyl residues. Polysaccharide C of MW 5.3 x 10(4) composed of a chain of 1,5-linked alpha-D-arabinofuranosyl, 1,4-linked beta-D-galactopyranosyl, 1,5-linked beta-D-xylopyranosyl, 1,4-linked beta-D-mannopyranosyl, 1-linked beta-D-glucopyranosyl residues, and the terminal beta-D-glucopyranosyl residues are attached to 3-O positions of 1,6-linked alpha-D-glucopyranosyl residues.
authors.affiliation: Beijing Institute of Radiation Medicine, Beijing, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.forename: Yan-Liang
authors.initials: YL
authors.lastname: Wang
authors.forename: Li
authors.initials: L
authors.lastname: Li
authors.forename: Liu
authors.initials: L
authors.lastname: Liu
authors.forename: Yu-Xin
authors.initials: YX
authors.lastname: Lu
authors.forename: Xiao-Chen
authors.initials: XC
authors.lastname: Cheng
authors.forename: Qing-Lin
authors.initials: QL
authors.lastname: Zhang
mesh_terms: D004365:Drugs, Chinese Herbal / Q000737:chemistry* / Q000302:isolation & purification*; D008401:Gas Chromatography-Mass Spectrometry; D019906:Nuclear Magnetic Resonance, Biomolecular; D018517:Plant Roots / Q000737:chemistry; D011134:Polysaccharides / Q000737:chemistry* / Q000302:isolation & purification*; D027003:Urticaceae / Q000737:chemistry*
chemical_list: D004365:Drugs, Chinese Herbal; D011134:Polysaccharides