摘要
对华南地区常见的6种竹材(麻竹、青皮竹、撑篙竹、沙罗单竹、粉单竹和吊丝竹)进行半纤维素的化学结构分析,首先对竹材进行亚氯酸钠处理脱除木质素得到综纤维素,再用二甲基亚砜(DMSO)抽提综纤维素得到半纤维素。采用离子色谱(IC)、凝胶渗透色谱(GPC)以及核磁共振(NMR)等分析方法对提取的半纤维素进行化学组成和结构的表征。研究发现:6种竹材综纤维素的半纤维素提取得率在3.9%~6.8%之间,木质素的脱除及纤维间的孔隙结构均对半纤维素的DMSO提取有正面影响。6种竹材半纤维素的最主要类型为乙酰化的阿拉伯糖-4-O-甲基-α-D-葡萄糖醛酸木聚糖,其次还有一定量的半乳葡萄甘露聚糖。提取的沙罗单竹半纤维素中含有一定量的淀粉,造成其具有较高的葡萄糖含量。6种竹材半纤维素的重均相对分子质量(M_(w))范围为31787~63707,数均相对分子质量(M_(n))范围为13457~23295,多分散性系数(PDI)为1.79~4.73,其中沙罗单竹的PDI为4.73,显著大于其他竹材,结构比其余5种竹材半纤维素更复杂。
In this study,the chemical composition and structure of hemicellulose of six common bamboo species in south China were characterized,including Dendrocalamus latiflorus Munro,Bambusa textilis McClure,Bambusa pervariabilis McClure,Schizostachyum funghomii McClure,Bambusa chungii McClure and Dendrocalamus minor(McClure)L.C.Chia&H.L.Fung.The bamboo was treated with sodium chlorite to remove the lignin and obtain the holocellulose,and then the holocellulose was extracted with dimethyl sulfoxide(DMSO)to obtain the hemicellulose.The chemical composition and structure of the extracted hemicellulose were characterized by ion chromatography(IC),gel permeation chromatography(GPC)and nuclear magnetic resonance analysis(NMR).The study showed that the hemicellulose yield from six bamboo hemicelluloses was between 3.9%and 6.7%,and both lignin removal and interfiber pore structure positively affected the DMSO extraction of hemicellulose.The major chemical structures/types of hemicelluloses were found to be acetylated L-arabinose-4-O-methyl-α-D-glucuronic acid-D-xylose,followed by a certain amount of galactoglucomannan.The extracted hemicellulose from S.funghomii contains a certain amount of starch,resulting in its higher glucose content.The molecular weight characteristics of hemicellulose extracted from bamboo species were investigated,revealing a weight-average molecular weight(M_(w))range from 31787 to 63707 and a number-average molecular weight(M_(n))range from 13457 to 23295.The polydispersity index(PDI),indicative of the breadth of the molecular weight distribution,varied from 1.79 to 4.73.Notably,S.funghomii exhibited a significantly higher PDI compared to other bamboo species,suggesting a more complex structural composition.
作者
刘晓欣
王宇晗
宋涛
项舟洋
LIU Xiaoxin;WANG Yuhan;SONG Tao;XIANG Zhouyang(State Key Laboratory of Pulp and Paper Engineering,South China University of Technology,Guangzhou 510640,China)
出处
《林产化学与工业》
北大核心
2025年第4期61-70,共10页
Chemistry and Industry of Forest Products
基金
国家科技基础资源调查专项(2019FY100900)。
关键词
半纤维素
化学组成
结构表征
竹
hemicellulose
chemical composition
structural characterization
bamboo
