title: Isolation, structural characterization and antioxidant activity of a new water-soluble polysaccharide from Acanthophyllum bracteatum roots.
abstract: ABPS-1, a new water-soluble polysaccharide with molecular weight of 26 kDa and a specific optical rotation of +170° (c 1.0, H(2)O), was extracted from the roots of Acanthophyllum bracteatum by warm water and further successively purified through DEAE-cellulose A52 and Sephadex G-100 columns. Monosaccharide analysis revealed that the ABPS-1 was composed of Glc, Gal and Ara with a relative molar ratio of 1.4:5.2:1.0. Its structural features were elucidated by a combination of FT-IR, methylation and GC-MS analysis, periodate oxidation and Smith degradation, partial acid hydrolysis and (13)C and (1)H NMR spectroscopy. The data obtained indicate that ABPS-1 possessed a backbone of α-(1→6)-linked Gal with branches attached to O-2 by α-1→linked Glc and at O-3 by α-1→linked Gal and by α-(1→3)-linked Ara. The in vitro antioxidant activity showed that ABPS-1 possesses DPPH radical-scavenging activity in a concentration-dependent manner with an EC(50) value of 2.6 mg/ml.
authors.affiliation: Shahrood University of Technology, Faculty of Agriculture, School of Agricultural Engineering, Shahrood, Iran. kamijahanbin@gmail.com
authors.forename: Kambiz
authors.initials: K
authors.lastname: Jahanbin
authors.forename: Ahmad Reza
authors.initials: AR
authors.lastname: Gohari
authors.forename: Sohrab
authors.initials: S
authors.lastname: Moini
authors.forename: Zahra
authors.initials: Z
authors.lastname: Emam-Djomeh
authors.forename: Paolo
authors.initials: P
authors.lastname: Masi
mesh_terms: D000975:Antioxidants / Q000494:pharmacology*; D001713:Biphenyl Compounds / Q000378:metabolism; D029748:Caryophyllaceae / Q000737:chemistry*; D002850:Chromatography, Gel; D016166:Free Radical Scavengers / Q000494:pharmacology; D008401:Gas Chromatography-Mass Spectrometry; D006868:Hydrolysis / Q000187:drug effects; D009682:Magnetic Resonance Spectroscopy; D010084:Oxidation-Reduction / Q000187:drug effects; D010851:Picrates / Q000378:metabolism; D018517:Plant Roots / Q000737:chemistry*; D011134:Polysaccharides / Q000737:chemistry* / Q000302:isolation & purification* / Q000494:pharmacology; D012995:Solubility / Q000187:drug effects; D013055:Spectrophotometry, Infrared; D014867:Water / Q000737:chemistry*
chemical_list: D000975:Antioxidants; D001713:Biphenyl Compounds; D016166:Free Radical Scavengers; D010851:Picrates; D011134:Polysaccharides; D014867:Water; C004931:1,1-diphenyl-2-picrylhydrazyl