广林9号桉叶木质素的结构表征  

Structural characterization of lignin from leaves of E.grandis × E.urophylla Guanglin No.9

作　　者：王继坤[1] 赵力超[1] 刘欣[1] 曹庸[1] 曹素芳[1] 

机构地区：[1]华南农业大学食品学院,广州510642

出　　处：《中国科技论文》2015年第12期1364-1368,共5页China Sciencepaper

基　　金：高等学校博士学科点专项科研基金资助项目(20114404120026);国家林业公益性重大行业科技专项资助项目(201104003)

摘　　要：为了综合利用桉叶资源,采用二氧六环法从广林9号桉叶中制备木质素,并对其进行了元素分析、功能基团测定、红外光谱分析、紫外光谱分析和核磁共振氢谱分析等结构表征。试验结果表明:所提取的桉叶木质素的C、H、O、N元素含量分别为w(C)=52.87%,w(H)=5.65%,w(O)=40.11%,w(N)=1.37%,甲氧基含量为16.09%,C9单元式为C9H9.86O4.69(OCH3)0.979,单元相对分子质量为222.0;桉叶木质素中酚羟基的质量分数为1.429%,羧基为1.01%,桉叶木质素每个C9单元中所含的的酚型α、酚型γ、非酚型α、非酚型γ的个数分别为0.005 0、0.003 4、0.004 7、0.005 9,总羰基个数为0.019;桉叶木质素在紫外光谱中的278和251nm处有较强吸收;红外光谱及核磁共振氢谱分析表明,桉叶木质素分子结构中含有较多数量的羟基、甲氧基、苯环等结构,属于愈创木基-紫丁香基型木质素。本研究为桉叶这一废弃性再生资源的进一步利用提供技术支持。For comprehensive utilization of the eucalyptus leaves,dioxane method was used to extract lignin from E.grandis × E.urophylla Guanglin No.9,and the lignin was structurally characterized by elemental analysis,determination of functional groups,Fourier Transform Infrared Spectroscopy,UV spectroscopy and 1 H-NMR.The results show that the contents of C, H,O,N extracted from eucalyptus leaves are 52.87%,5.65%,40.11% and 1.37%,respectively.The content of methoxyl group is 16.09%.The unit formula of C9 is C9 H9.86 O4.69 （OCH3 ）0.979 and the relative molecular mass of C9 unit is 222.0.The mass fraction of phenolic hydroxyl and carboxyl of lignin from eucalyptus leaves is 1.429% and 1.01%,respectively.The num-ber of phenolicα,phenolicγ,non-phenolicα,non-phenolicγ in C9 unit of lignin from eucalyptus leaves is 0.005 0,0.003 4, 0.004 7,0.005 9,respectively,and the total number of carbonyl groups is 0.019.Eucalyptus leaves lignin has strong absorption at 278 nm and 251 nm in the UV spectrum.Analysis through infrared spectroscopy and 1 H-NMR spectroscopy show that the molecular structure of the lignin contains a large number of hydroxyl,methoxy group,benzene ring structure and belongs to a kind of guaiacyl-syringyl lignin.This study provides further support for the use of eucalyptus leaves which are the waste of re-newable resources.

关 键 词：桉叶 木质素 红外光谱 紫外光谱 核磁共振氢谱 

分 类 号：O636.2[理学—高分子化学]