阿魏酸酯酶和纤维素酶在水解汽爆稻草中的协同作用

Synergistic effect of feruloyl esterase and cellulase in hydrolyzation of steam-exploded rice straw

摘要:

利用阿魏酸酯酶, 水解天然木质纤维素原料中半纤维素与木质素之间的阿魏酸酯键, 从破坏两者共价键连接的角度, 探索阿魏酸酯酶促进纤维素酶水解汽爆稻草中纤维素的可行性。结果显示, 当阿魏酸酯酶加入量为240 mu/g底物、水解72 h时, 汽爆稻草纤维素的酶解率、不溶性底物失重率较不加阿魏酸酯酶分别增加了32.00%、32.77%; 阿魏酸酯酶(300 mu/g底物)作用120 min后, 纤维素酶对汽爆稻草纤维素的酶解率、不溶性底物失重率分别增加了29.85%、32.48%。通过比较不同酶法处理后的汽爆稻草的可及度和红外光谱图发现, 阿魏酸酯酶能有效地水解原料中的酯键, 提高原料可及度50%以上。由此表明, 阿魏酸酯酶和纤维素酶之间存在较大的协同作用, 添加阿魏酸酯酶能够提高纤维素酶对天然木质纤维素的酶解效率。

Abstract:

Ferulic acid esterase (FAE) was used to hydrolyze feruloyl ester linkages between hemicellulose and lignin in natural lignocellulose, and the possibility of FAE accelerating cellulase to hydrolyze steam-exploded rice straw by breaking covalent linkages was studied. When the dosage of FAE was 240 mu/g substrate, the cellulose conversion rate and the weight-loss rate of insoluble substrate at 72 h were respectively 32.00% and 32.77%, more than without using FAE; Cellulose conversion rate and the weight-loss rate of insoluble substrate were respectively 29.85% and 32.48% with FAE (300 mu/g substrate) processing time of 120 min. By comparison of the accessibility and FT-IR spectra of lignocellulosic material treated by different enzyme methods, it indicated that FAE hydrolyzed some ester bonds within it, and improved the accessibility by over 50%. It is concluded that FAE and cellulase have great synergistic effect, and FAE can help cellulase hydrolyze natural lignocellulose and enhance hydrolytic efficiency.