Investigation of the alkaline hydrogen peroxide pretreatment: From cellulose saccharification to lignin isolation

Alkaline hydrogen peroxide (AHP) pretreatment, a green and effective technology for biomass fractionation, was studied to overcome the recalcitrance of bamboo for lignin isolation and facilitating enzymatic saccharification. In order to explore the impact of AHP pretreatment on the cellulose saccharification of bamboo, the glucan/xylan recovery, lignin removal, and structural properties of solid substrate were investigated in this research. AHP pretreatment at 90 ℃ for 60 min with 3.0 % H2O2 resulted in the maximum glucan/xylan hydrolysis yield reaching 90.62 % and 88.30 %, respectively. Specially, for the first time, the recovered lignin from the AHP liquid possesses up to 59.84/100Ar of β-O-4 linkages, abundant ferulic acid (FA), and p-coumarate (pCE) structures, as well as a homogeneous molecular structure with high purity (84.04%-96.20%) and preferable antioxidant activities (IC50: 0.015–0.018 mg/mL). These results provided theoretical support for the comprehensive valorization of lignocellulose, which is favorable for achieving viable biorefineries. •AHP is effective in enhancing cellulose saccharification and lignin removal.•Solid substrates presented 90.62% and 88.30% glucan/xylan hydrolysis yield.•Up to 58.74% lignins with high purity (84.04%-96.20%) were recovered.•Regenerated lignins showed well-preserved β-O-4 linkages (54.76–59.84/100 Ar).