Facilitating enzymatic hydrolysis efficiency of rape straw by pretreatment with a novel glycerol-based deep eutectic solvent

Deep eutectic solvent (DES) pretreatment plays an indispensable role in destroying the natural anti-degradation barrier structure of lignocellulose. Here, the cetyltrimethylammonium bromide and glycerol were used to syn-thesize novel DES and introduced to the pretreatment process to facilitate the enzymatic hydrolysis efficiency of rape straw (RS). The results showed that the delignification and xylan removal could extremely reach 46.1% and 52.7% under optimal conditions (molar ratio of 1:6, 200 degrees C, 90 min), respectively. It also resulted in 171.4 mg/g higher accessibility, 7.2% higher crystallinity, and 122.3 m2/g lower lignin surface area in RS concerning morphological changes of deconstructed and porous cell wall structure. Ultimately, the reducing sugar yield of RS was increased from 27.4% to 67.9% after pretreatment with this type of DES. This study exploited a novel DES for facilely reducing the recalcitrance of lignocellulose and a promising process for efficient saccharification using renewable biomass.

Automated summary

In this study, a novel deep eutectic solvent (DES) was used for pretreatment of rape straw, resulting in high removal efficiency of lignin and xylan, improved accessibility, crystallinity, and lignin surface area. The sugar yield of pretreated rape straw was significantly increased.