苯氧乙醇耦合酸/碱预处理竹屑中残留木质素对其纤维素酶水解的影响  

Effect of Residual Lignin on the Cellulase Hydrolysis of Bamboo Residues Pretreated with Phenoxylethanol Coupled Acid/Alkali

作　　者：赵晓雪 郑雅月 李若琳 姚双全[2] 勇强[1] 黄曹兴[1,2] 周雪莲 ZHAO Xiaoxue;ZHENG Yayue;LI Ruolin;YAO Shuangquan;YONG Qiang;HUANG Caoxing;ZHOU Xuelian(Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Products,Nanjing Forestry University,Nanjing 210037,China;Guangxi Key Laboratory of Clean Pulp&Papermaking and Pollution Control,College of Light Industry and Food Engineering,Guangxi University,Nanning 530004;Institute of Chemical Industry of Forest Products,CAF,Key Lab.of Biomass Energy and Material,Jiangsu Province,Nanjing 210042,China)

机构地区：[1]南京林业大学、江苏省林业资源高效加工利用协同创新中心,江苏南京210037 [2]广西清洁化制浆造纸与污染控制重点实验室、广西大学轻工与食品工程学院,广西南宁530004 [3]中国林业科学研究院林产化学工业研究所、江苏省生物质能源与材料重点实验室,江苏南京210042

出　　处：《林产化学与工业》2024年第4期87-99,共13页Chemistry and Industry of Forest Products

基　　金：国家自然科学基金资助项目(32271796);广西清洁化制浆造纸与污染控制重点实验室开放基金资助项目(2023GXZZKF01)。

摘　　要：以竹加工剩余物竹屑为对象,探究苯氧乙醇耦合酸/碱溶液预处理竹屑,分析了预处理后竹屑中残留木质素的结构特性和理化性质,并通过荧光光谱和表面等离子共振技术揭示不同方法预处理后的竹屑中残留木质素对纤维素酶的非生产性吸附机制。结果表明:随着苯氧乙醇体系中酸/碱加入,酶解72 h预处理竹屑的纤维素酶解得率从9.39%提高到67.38%和55.41%。对残留木质素进行表征,发现当温度升高,木质素的紫丁香基/愈创木基结构单元(S/G)的比值增高,且木质素相对分子质量分布更均匀。2D-HSQC NMR、^(31)P NMR、表面电荷及疏水性等测试结果表明:木质素对纤维素酶水解的抑制作用与其酚羟基含量、疏水性和Zeta电位有关。荧光光谱和表面等离子共振技术表明:木质素与纤维素酶作用的主要驱动力类型与预处理温度、苯氧乙醇体系中酸/碱溶液的加入相关。不同预处理竹屑中木质素与纤维素酶的亲和力不同,其中纯苯氧乙醇预处理竹屑中木质素与纤维素酶的亲和力最高,其次为纯酸/纯碱溶液预处理的木质素,而苯氧乙醇与酸/碱耦合预处理竹屑中木质素对纤维素酶的亲和力最低。In this study,bamboo chips,the residue of bamboo processing,were used as the object to investigate the structural characteristics and physicochemical properties of residual lignin in bamboo chips pretreated by phenoxylethanol coupled with acid/alkali solutions.The non-productive adsorption mechanism of residual lignin on cellulase in different pretreated bamboo chips was revealed using fluorescence spectroscopy and surface plasmon resonance techniques.The results indicated that as the increases of V(phenoxylethanol)∶V(acid/alkali)ratio,the cellulose hydrolysis yield of pretreated bamboo chips increases from 9.39%to 67.38%/49.87%.Characterization of residual lignin revealed an increase in the syringyl/guaiacyl(S/G)ratio of lignin in pretreated bamboo chips as the temperature and the V(phenoxylethanol)∶V(alkali)ratio increase,and the lignin molecular weight was more uniform.The characterization results of 2D-HSQC NMR,^(31)P NMR,surface charge and hydrophobicity indicated that the inhibitory effect of lignin on cellulose hydrolysis was directly proportional to its phenolic hydroxyl content,hydrophobicity,and Zeta potential.Fluorescence spectroscopy and surface plasmon resonance techniques suggested that the primary driving force types for lignin-cellulase interaction were related to pretreatment temperature,phenoxylethanol volume,and acid/alkali solution volume.The affinity of lignin and cellulase from different pretreated bamboo chips was different.Among them,the highest affinity observed in pure phenoxylethanol pretreated bamboo chips,followed by pure acid/pure alkali solution pretreated lignin,and the lowest affinity was observed in phenoxylethanol and acid/alkali coupled pretreated bamboo chips.

关 键 词：竹屑 苯氧乙醇 酸/碱预处理 残留木质素 酶水解 

分 类 号：TQ35[化学工程]