Surfactant-assisted alkaline pretreatment and enzymatic hydrolysis of Miscanthus sinensis for enhancing sugar recovery with a reduced enzyme loading
Xiyu Cheng, Ying Luo, Yifan Gao, Shen Li, Chunming Xu, Shangyuan Tang, Yongkun Yang, Zehua Zhang, He Jiang, Hanli Xu, Shuobo Shi, Qiong Yan
Abstract
Surfactants play a vital role in the delignification and saccharification of lignocellulosic biomass. A strategy for coupling surfactant-assisted alkaline pretreatment (SAP) with surfactant-assisted enzymatic hydrolysis (SEH) has been proposed for improving sugar recovery from a potential energy crop, Miscanthus sinensis . Poly (ethylene glycol) 2000 (PEG 2000) was found to be more efficient in SAP than in other tested surfactants. Compositional and structural analysis revealed that the SAP process with 1% of PEG 2000 produced more efficient lignin removal and microstructure disruption of the pretreated sample, thus indicating much higher reducing sugar yields of 544.4–601.2 mg/g compared to the samples that were untreated or pretreated by alkali alone. Moreover, SEH with 1% Tween 80, which could block the lignin-enzyme interactions, produced a substantial reduction of 33.3% in the enzyme loading to achieve a higher sugar recovery from the SAP sample.