【作者】 张雪红； 林翠梧；

【Author】 ZHANG Xue-hong 1,2,LIN Cui-wu 1 1.School of Chemistry and Chemical Engineering,Guangxi University,Nanning 530004,China 2.School of Chemistry and Life Science,Guangxi Teachers Education University,Nanning 530001,China

【机构】 广西大学化学化工学院； 广西师范学院化学与生命科学学院；

【摘要】 多糖由于拥有抗肿瘤、抗病毒、抗氧化、免疫调节、降糖降脂等众多生物活性,吸引了很多研究人员的目光。本文以抽取纤维后的废弃剑麻渣为原料,采用水提醇沉和Sevag法脱蛋白,得到剑麻粗多糖CSP。粗多糖CSP经DEAE-Celluose纤维素柱色谱脱色分离、SephacrylS-300HR凝胶柱多次纯化后得到一个精制的剑麻多糖SP3。高效凝胶渗透色谱法测定SP3的纯度为99.4%,平均分子量约为16700Da。单糖组成分析可知SP3由Rha、GalA、Gal、Man、Glc和Xyl以1.7:1.0:1.1:0.1:0.2:0.1的摩尔比组成。综合采用核磁共振波谱、气质连用和液质连用技术,结合部分酸水解、高碘酸氧化和Smith降解以及甲基化分析对剑麻多糖SP3进行了结构鉴定。结果发现SP3的主链由交替的1,2-α-L-Rhap、1,4-α-D-GalpA和1,4-α-D-Galp残基以7:3:4的摩尔比组成。SP3主链上的鼠李糖残基中约有25%被分支,1个单一的甘露糖残基或1个单一的木糖残基通过1,2-α-L-Rhap上的O-4位链接到主链上,二者的摩尔比是1:1。同时,SP3主链上的半乳糖残基中约有46%被分支,1个单一的1-β-D-Galp残基通过1,4-β-D-Galp上的O-2位链接到主链上。另外,部分半乳糖残基的O-2位上的羟基被甲氨基取代。更多还原

【Abstract】 Polysaccharides from plants,animals and microorganisms have aroused the interest of many researchers,due to their many biological activities,such as antioxidant,antitumor,antiviral,anticoagulant,and immune-stimulating.The crude polysaccharide(CSP) was obtained from the residue after extracting fiber by hot water extraction,ethanol precipitation and deproteinization using Sevag method.After destaining and separating by DEAE-cellulose anion exchange chromatography and Sephacryl S-300 HR gel filtration chromatography,a water-soluble polysaccharides(SP3) was obtained.The purity of SP3 and average molecular weight were determined by high performance gel permeation chromatography,and they are 99.4% and about 16700 Da,respectively.The sugar composition analysis indicated that SP3 was composed of Rha,GalA,Gal,Man,Glc,and Xyl in a molar ratio of 1.73:1.00:1.08:0.10:0.20:0.09.The structures of SP3 was investigated by NMR,GC-MS,LC-MS,acid hydrolysis,methylation analysis,periodate oxidation and Smith degradation.The structure analysis indicated that the SP3 was comprised of a backbone of alternating 1,2-linked-α-L-Rhap,1,4-linked-α-D-GalpA,and 1,4-linked-α-D-Galp residue in a molar ratio of 7.0:3.0:4.0.Around 25% of rhamnose of the backbone and 46% galactose were branched,a single Manp or Xyl residue was attached to the O-4 position of 1,2-linked-α-L-Rhap residues,and a single 1-β-D-Galp residue was attached to the O-2 position of 1,4-linked-β-D-Galp residues.In addition,some hydroxyl group on the O-2 position of 1,4-linked-α-D-Galp was substituted by methylamino.更多还原