Employing deep eutectic solvent synthesized by cetyltrimethylammonium bromide and ethylene glycol to advance enzymatic hydrolysis efficiency of rape straw

An efficient deep eutectic solvent (DES) was synthesized by cetyltrimethylammonium bromide (CTAB) and ethylene glycol (EG) and employed to treat rape straw (RS) for advancing enzymatic saccharification in this work. By optimizing the pretreatment parameters, the results displayed that the novel DES was strongly selective towards removing lignin and xylan while preserving cellulose. Under optimum conditions with 1:6 of CTAB: EG in DES, 180 degrees C and 80 min, the enzymatic hydrolysis efficiency of RS was enhanced by 46.0% due to the 62.2% of delignification and 53.2% of xylan removal during CTAB: EG pretreatment. In terms of the recalcitrant structure of RS, DES pretreatment caused the increment of cellulosic accessibility, reduction of hydrophobicity and surface area of lignin, and migration of cellulosic crystalline structure, which was associated with its enzymatic hydrolysis efficiency. Overall, this study presented an emerging method for the effective fractionation and valorization of lignocellulosic biomass within biorefinery technology.

Automated summary

An efficient deep eutectic solvent (DES), synthesized using cetyltrimethylammonium bromide (CTAB) and ethylene glycol (EG), was used to enhance enzymatic saccharification of rape straw (RS). The optimized pretreatment parameters showed that the DES selectively removed lignin and xylan while preserving cellulose. DES pretreatment resulted in an increased enzymatic hydrolysis efficiency of RS by 46.0% due to the removal of 62.2% lignin and 53.2% xylan. The study also revealed that DES pretreatment improved cellulosic accessibility, reduced lignin hydrophobicity and surface area, and caused migration of cellulosic crystalline structure, contributing to enhanced enzymatic hydrolysis efficiency. Overall, this study presented an emerging method for the effective fractionation and valorization of lignocellulosic biomass within biorefinery technology.