Comparative Study of Water-soluble and Alkali-soluble Hemicelluloses Extracted by Hydrothermal Pretreatment  

作　　者：LianHua Fu LingYan Meng YaYu Li MingGuo Ma 

机构地区：[1]Engineering Research Center of Forestry Biomass Materials and Bioenergy,Beijing Key Laboratory of Lignocellulosic Chemistry,College of Materials Science and Technology,Beijing Forestry University,Beijing,100083,China

出　　处：《Paper And Biomaterials》2017年第1期1-9,共9页造纸与生物质材料（英文）

基　　金：financial support from the Fundamental Research Funds for the Central Universities(No.JC2013-3,BLYJ201616);Beijing Higher Education Young Elite Teacher Project(No.YETP0763)

摘　　要：The purpose of this study was to explore the differences of the hemicelluloses extracted by hydrothermal pretreatment using water and alkaline solutions(Na OH or KOH). The physicochemical properties and structural characteristics of two water-soluble and four alkali-soluble hemicelluloses extracted from the triploid of Populus tomentosa Carr. through the hydrothermal pretreatment were comparatively studied. It was observed that the alkalis(Na OH and KOH) were more effective than distilled water as extractants. Sugar analysis showed that xylose(66.83%~86.49%) was the major constituent, followed by glucose(6.83%~18.49%). Mannose(1.40%~8.42%), galactose(2.17%~4.05%), and arabinose(0.21%~2.26%) were also detected in the hemicellulosic fractions. The results of gelpermeation chromatography(GPC) indicated that the hemicelluloses extracted using the alkaline solutions had relatively higher molecular weights than those solubilized in distilled water. Further, based on spectroscopic ~1Hnuclear magnetic resonance(~1H-NMR) and two-dimensional heteronuclear singular quantum correlation(2D-HSQC) analyses, it was confirmed that the hemicellulosic fractions had a major structure of(1→4)-b-D-xylan and a minor structure of(1→4)-a-D-glucan with small amounts of substituted sugars and glucuronic acid attached.The purpose of this study was to explore the differences of the hemicelluloses extracted by hydrothermal pretreatment using water and alkaline solutions （NaOH or KOH）. The physicochemical properties and structural characteristics of two water-soluble and four alkali-soluble hemicelluloses extracted from the triploid of Populus tomentosa Carr. through the hydrothermal pretreatment were comparatively studied. It was observed that the alkalis （NaOH and KOH） were more effective than distilled water as extractants. Sugar analysis showed that xylose （66.83%-86.49%） was the major constituent, followed by glucose （6.83%-18.49%）. Mannose （1.40%-8.42%）, galactose （2.17%-4.05 %）, and arabinose （0.21%-2.26%） were also detected in the hemicellulosic fractions. The results of gelpermeation chromatography （GPC） indicated that the hemicelluloses extracted using the alkaline solutions had relatively higher molecular weights than those solubilized in distilled water. Further, based on spectroscopic 1H- nuclear magnetic resonance （1^H-NMR） and two-dimensional heteronuclear singular quantum correlation （2D-HSQC） analyses, it was confirmed that the hemicellulosic fractions had a major structure of （1 →4）-β-D-xylan and a minor structure of （1→4）-α-D-glucan with small amounts of substituted sugars and glucuronic acid attached.

关 键 词：water-and alkali-soluble hemicelluloses hemicellulose structure hydrothermal pretreatment 

分 类 号：TQ352.1[化学工程]