STRUCTURAL ASSOCIATION OF XYLAN AND GLUCANS IN THE CELL WALL OF EUCALYPTUS GLOBULUS L.

摘要：

The glucan-glucuronoxylan complex was isolated from Eucalyptus globulus wood by hot water extraction and subjected to enzymatic hydrolysis with xylanase. The fraction of acidic xylo-oligosaccharides structurally associated with glucan was isolated using semipreparative ligand-exchange/size exclusion chromatography and thoroughly analyzed by electrospray ionization tandem mass spectrometry. The results of structural analysis indicated that glucan chains are bonded to glucuronoxylan (GX) via terminal 4-O-methylglucuronic residues (MeGlcA). The relatively labile (1→6) linkage between glucan backbone and MeGlcA (→6)-D-Glcp-(l→2)-4-O -MeGlcAp-(1→) explains the easy degradation of glucanglucuronoxylan complex under acidic and alkaline conditions. Structurally associated with heteroxylan glucan was tentatively assigned to bulk noncellulosic β-glucan prevailing in gelatinous-type cell walls of tension wood.

关键词： Eucalyptus globules glucuronoxylan glucan electrospray ionization mass spectrometry structuralassociation

作者: Sara A. B. Lisboa Sónia O. Prozil, Dmitry V.Evtuguin M. Rosário Domingues

作者单位: CICECO/ Mass Spectrometry Group, Department of Chemistry, University ofAveiro, 3810-193 Aveiro,Portugal

会议类型: 国际会议

会议名称: 16th International Symposium on Wood,Fiber and Pulping Chemistry(第十六届木材、纤维及制浆化学国际会议)

会议地点: 天津

会议语种:英文

页码: 18-23

在线出版日期: 2011-06-08（万方平台首次上网日期，不代表论文的发表时间）