title: Characterization of mucilage polysaccharides, arabinogalactanproteins and cell-wall hemicellulosic polysaccharides isolated from flax seed meal: A wealth of structural moieties.
abstract: The present study aimed at analyzing the structural features of seed mucilage and cell-wall polysaccharides which accounted for 41% of the mass of flax meal (FM). A combination of high molar-mass mucilage-like polysaccharides (rhamnogalacturonan and arabinoxylan) was released from FM in water, together with arabinogalactan proteins and glucans. About half of FM homogalacturonans was extracted using a calcium chelator and boiling water. Hemicellulosic xyloglucans and xylans were further extracted with 1M KOH, in ∼13% FM-sugars yield. Structural characterization of the xyloglucan using specific enzyme hydrolysis, ion exchange chromatography (HPAEC) and matrix assisted laser desorption ionization-time-of-flight (MALDI-TOF) mass spectroscopy showed the presence of XXXG type xyloglucan, but also that of XXGG-structure, possibly characteristic of flax seeds. Hydrolysis of xylans with endo-(1→4)-β-D-xylanase, and analysis of the neutral and acidic oligosaccharides by MALDI-TOF-MS showed that xylan consisted of β-(1→4)-linked-D-xylopyranose backbone with some zones (DP 5-7) substituted with 4-O-MeGlcA\GlcA\Glc residues.
authors.affiliation: Natural Products Laboratory, Department of Chemistry, The University of Burdwan, WB 713 104, India.
authors.forename: Sayani
authors.initials: S
authors.lastname: Ray
authors.forename: Florence
authors.initials: F
authors.lastname: Paynel
authors.forename: Claudine
authors.initials: C
authors.lastname: Morvan
authors.forename: Patrice
authors.initials: P
authors.lastname: Lerouge
authors.forename: Azeddine
authors.initials: A
authors.lastname: Driouich
authors.forename: Bimalendu
authors.initials: B
authors.lastname: Ray
mesh_terms: D002473:Cell Wall / Q000737:chemistry*; D002614:Chelating Agents / Q000737:chemistry; D019597:Flax / Q000737:chemistry*; D006868:Hydrolysis; D009088:Mucoproteins / Q000032:analysis* / Q000737:chemistry; D010368:Pectins / Q000737:chemistry; D062087:Plant Mucilage / Q000032:analysis* / Q000737:chemistry; D010940:Plant Proteins / Q000032:analysis / Q000737:chemistry; D011134:Polysaccharides / Q000032:analysis* / Q000737:chemistry; D012639:Seeds / Q000737:chemistry*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods; D014574:Uronic Acids / Q000737:chemistry; D014867:Water / Q000737:chemistry; D014990:Xylans / Q000737:chemistry
chemical_list: D002614:Chelating Agents; D009088:Mucoproteins; D062087:Plant Mucilage; D010940:Plant Proteins; D011134:Polysaccharides; D014574:Uronic Acids; D014990:Xylans; C006619:arabinogalactan proteins; D014867:Water; C007916:hemicellulose; D010368:Pectins; C085118:arabinoxylan