Elevating monosaccharides and monophenols production from wheat straw components via in-situ tailored lignin with deep eutectic solvents

Abstract

Efficient biomass fractionation is key to enhancing the productivity and profitability of biorefining but faces challenges such as strong carbon–carbon bonds in lignin and irreversible condensation reactions during extraction. In this study, hydroxyl-containing nucleophilic reagents are integrated into acidic deep eutectic solvents (DESs) for wheat straw pretreatment, achieving over 74.3 % lignin removal and 94.3 % cellulose retention. This method preserves more than 98.6 % of the β–O–4 linkages in lignin, and the nucleophilic reagents, introduced in-situ at the benzylic position of lignin, act as both a surfactant on cellulose and a stabilizer for isolated lignin. This dual functionality enhances enzymatic hydrolysis, resulting in 75.3 wt% glucose and 51.0 wt% xylose yields. Additionally, the pyrolysis yield of methoxy-deficient monophenols increases from 27.7 wt% to 38.6 wt%. This approach effectively addresses key challenges in biomass fractionation, improving carbon efficiency and facilitating the full valorization of lignocellulose.