Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing 210037, China; College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China.
College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China.
Bioresour Technol. 2017 Nov;244(Pt 1):92-99. doi: 10.1016/j.biortech.2017.07.074. Epub 2017 Jul 16.
A novel pretreatment process of corn stover was established in this study by in situ modification of lignin with poly (ethylene glycol) diglycidyl ether (PEGDE) during low temperature alkali pretreatment. The addition of PEGDE obviously improved the enzymatic hydrolysis by covalently modifying the residual lignins in substrates. Under the optimized conditions (pretreated with 10% (w/w) NaOH and 10% (w/w) PEGDE at 70°C for 2.5h), the total fermentable sugar yield was increased by 46.4%, from 23.7g to 34.7g per 100g raw materials. Additionally, the remaining activities of exo-glucanase and β-glucosidase in supernatant were increased by 58.6% and 40.6% respectively, demonstrating that the enhancement of enzymatic hydrolysis was mainly due to the alleviation of enzyme non-productive binding. Although the isolated lignin modified with PEGDE enhanced the enzymatic hydrolysis of substrates as well, this in situ lignin modification provided an efficient but simple way to improve enzymatic saccharification.
本研究通过在低温堿预处理过程中用聚乙二醇二缩水甘油醚（PEGDE）原位修饰木质素，建立了一种新颖的预处理玉米秸秆的方法。PEGDE 的添加通过共价修饰基质中残留的木质素，明显提高了酶水解性能。在优化条件下（用 10%（w/w）NaOH 和 10%（w/w）PEGDE 在 70°C 预处理 2.5h），每 100g 原料的总可发酵糖产率从 23.7g 提高到 34.7g，提高了 46.4%。此外，上清液中外切葡聚糖酶和β-葡萄糖苷酶的剩余活性分别提高了 58.6%和 40.6%，表明酶非生产性结合的缓解是提高酶水解的主要原因。尽管分离出的用 PEGDE 修饰的木质素也能增强底物的酶水解，但这种原位木质素修饰提供了一种有效但简单的方法来提高酶糖化。
