Enhancement of lignosulfonate-based polyoxyethylene ether on enzymatic hydrolysis of lignocelluloses

• Effect of LS-PEG molecular structure on enzymatic hydrolysis was investigated.
• When LS-PEG was compounded with CTAB, enzymatic hydrolysis further increased.
• LS-PEG interacted with CTAB to form a similar non-ionic surfactant.

Effect of the molecular structure of lignosulfonate-based polyoxyethylene ether (LS-PEG) on the enzymatic hydrolysis of Avicel and corn stover was investigated. With the increase of PEG contents and Mw of LS-PEG, glucose yield of corn stover increased from 16.7% to 51.9%. When LS-PEG was compounded with cationic surfactant cetyltrimethylammonium bromide (CTAB), the enhancement of glucose yield of corn stover was further increased from 45.3% to 62.8%. Sulfonic group of LS-PEG preferentially interacted with quaternary ammonium group of CTAB by the electrostatic attraction to form a similar non-ionic surfactant CTAB-LS-PEG. CTAB-LS-PEG showed electrically neutral and more hydrophobic, and blocked more nonproductive adsorption of cellulase on the lignin. Therefore, CTAB-LS-PEG enhanced enzymatic hydrolysis efficiency of lignocelluloses more significantly. The understanding developed in this study can help to develop potential approaches and strategies for effective application of lignosulfonate to improve bioconversion of lignocellulosic biomass.