漆酶催化提高纸浆中-COOH含量机理研究  

The Study of Mechanism of Increasing the Amount of -COOH through Laccase Catalyzed Link Glutamic Acid

作　　者：刘建祥[1] 万金泉[1,2] 马邕文[1,2] 王艳[2] 

机构地区：[1]华南理工大学制浆造纸工程国家重点实验室,广东广州510640 [2]华南理工大学环境与能源学院,广东广州510006

出　　处：《造纸科学与技术》2016年第1期63-66,71,共5页Paper Science & Technology

基　　金：国家自然科学基金项目(NO.31170551);制浆造纸工程国家重点实验室开放基金项目(NO.201306)

摘　　要：从硫酸盐法桉木浆黑液中分离纯化得到硫酸盐木素,选取阿魏酸和丁香酸作为木质素模型物,探究谷氨酸在漆酶作为催化剂的条件下连接到木质素上的反应机理。结果表明:漆酶可以催化氧化木质素形成苯氧自由基或通过重排形成苯醌结构,自由基之间可通过耦合反应按摩尔比1∶1发生聚合;谷氨酸可与C5位置上的自由基发生Michael加成反应,使其自身连接到木质素上,在酸性条件下,对于苯环侧链末端醛基,C=O键可转变为C=N键将谷氨酸连接到木质素上,增加纸浆中的-COOH含量;In this study,kraft lignin was isolated by acid precipitation method from the kraft cooking black liquor which was obtained from eucalyptus wood pulping. Ferulic acid and syringic acid were chosen as the lignin model compounds to research the mechanism of laccase catalyzed lignin with glutamic acid. Result showed that laccase can oxidize lignin to phenoxy radicals which can transformed to benzoquinone structure through rearrangement reaction,coupling reactions proceeded following creation of radicals yielded 1∶ 1 coupling products. Based on Michael addition reaction,glutamic acid was linked onto the position C5 of lignin radicals. Similarly,glutamic acid can connect to phenyl side chain where aldehyde（ C = O） transform to C = N bonding.

关 键 词：漆酶 硫酸盐木素 模型物 谷氨酸 自由基耦合反应 

分 类 号：O611.2[理学—无机化学]