Improving enzymatic saccharification of corn stover via thioglycolic acid-mediated Fenton pretreatment

Fenton pretreatment is known as a green and mild approach, but it is usually time-consuming and inefficient in promoting lignocellulose enzymatic hydrolysis. Here we demonstrate that thioglycolic acid (TA) significantly accelerates Fenton pretreatment (FP) of corn stover (CS) and improves enzymatic hydrolysis of cellulose and xylan. The results showed that the reducing sugar yield of CS reached 77.0% with TA-assisted FP in only 16 h, while it was only 34.1% and 38.0% with FP alone in 16 h and 72 h, respectively. Via examination of the changes of composition, physical and chemical characteristics of CS before and after pretreatment, it was found that TA-assisted FP greatly improved the removal of hemicellulose and lignin, resulting in increment of the pore volume, pore size and cellulose exposure of CS substrate, which together promoted the enzymatic saccharification of CS.