title: A new method for the quantification of monosaccharides, uronic acids and oligosaccharides in partially hydrolyzed xylans by HPAEC-UV/VIS.
abstract: A new method for the chemical characterization of xylans is presented, to overcome the difficulties in quantification of 4-O-methyl-α-D-glucuronic acid (meGlcA). In this regard, the hydrolysis behavior of xylans from beech and birch wood was investigated to obtain the optimum conditions for hydrolysis, using sulfuric acid. Due to varying linkage strengths and degradation, no general method for complete hydrolysis can be designed. Therefore, partial hydrolysis was applied, yielding monosaccharides and small meGlcA containing oligosaccharides. For a new method by HPAEC-UV/VIS, these samples were reductively aminated by 2-aminobenzoic acid. By quantification of monosaccharides and oligosaccharides, as well as comparison with borate-HPAEC and (13)C NMR-spectroscopy, we revealed that the concentrations meGlcA are significantly underestimated compared to conventional methods. The detected concentrations are 85.4% (beech) and 76.3% (birch) higher with the new procedure. Furthermore, the quantified concentrations of xylose were 9.3% (beech) and 6.5% (birch) higher by considering the unhydrolyzed oligosaccharides as well.
authors.affiliation: Department of Wood Science, University of Hamburg, Leuschnerstr. 91 b, 21031, Hamburg, Germany. Electronic address: dominic.lorenz@uni-hamburg.de.
authors.forename: Dominic
authors.initials: D
authors.lastname: Lorenz
authors.affiliation: Thünen-Insitute of Wood Research, Leuschnerstr. 91 b, 21031, Hamburg, Germany. Electronic address: nicole.erasmy@ti.bund.de.
authors.forename: Nicole
authors.initials: N
authors.lastname: Erasmy
authors.affiliation: Department of Wood Science, University of Hamburg, Leuschnerstr. 91 b, 21031, Hamburg, Germany. Electronic address: youssef.akil@uni-hamburg.de.
authors.forename: Youssef
authors.initials: Y
authors.lastname: Akil
authors.affiliation: Department of Wood Science, University of Hamburg, Leuschnerstr. 91 b, 21031, Hamburg, Germany. Electronic address: bodo.saake@uni-hamburg.de.
authors.forename: Bodo
authors.initials: B
authors.lastname: Saake
mesh_terms: D002852:Chromatography, Ion Exchange / Q000379:methods*; D004563:Electrochemistry; D006868:Hydrolysis; D057230:Limit of Detection; D009005:Monosaccharides / Q000032:analysis* / Q000737:chemistry; D009844:Oligosaccharides / Q000032:analysis* / Q000737:chemistry; D013056:Spectrophotometry, Ultraviolet / Q000379:methods*; D014574:Uronic Acids / Q000032:analysis* / Q000737:chemistry; D014990:Xylans / Q000737:chemistry*
chemical_list: D009005:Monosaccharides; D009844:Oligosaccharides; D014574:Uronic Acids; D014990:Xylans
keywords: 2-Aminobenzoic acid (PubChem CID: 227); 4-O-Methyl-α-D-glucuronic acid; 4-O-Methyl-α-D-glucuronic acid (PubChem CID: 446874); Anthranilic acid; Borane-2-picoline (PubChem CID: 16217944); Borate-HPAEC; HPAEC-UV/VIS; Partial hydrolysis; Reductive amination