%A ZHANG Min, ZHOU Jie, ZHANG Ding-wei, YU Heng, LI Yao, JIANG Ting, OUYANG Jia %T Mechanism of Polyethylene Glycol Treatment for Improvement of Enzymatic Hydrolysis of Acid Steam-exploded Corn Straw %0 Journal Article %D 2015 %J Chemistry and Industry of Forest Products %R 10.3969/j.issn.0253-2417.2015.05.013 %P 79-84 %V 35 %N 5 %U {http://www.cifp.ac.cn/CN/abstract/article_2147.shtml} %8 2015-10-28 %X In order to investigate the mechanism of PEG4000 addition on enhancement of the enzymatic hydrolysis using the acid steam-exploded corn straw(ASCS) as the raw material, its physochemical properties such as composition, BET and elemental analysis of the substrate, were studied. Based on these results, the effect of PEG on hydrolysis process was studied, and the mechanism was also explored. Moreover, structural changes of substrates before and after hydrolysis were analyzed by FT-IR and SEM. Acid steam-exploded corn straw had a high lignin content with a large BET surface area. With the dose of cellulase 15 FPIU/g (calculated by cellulose) and glucosidase 30 U/g, the glucose conversion of 50 g/L ASCS could reach 76.4% by hydrolysis time of 24h. PEG addition could effectively improve the enzymatic hydrolysis of the acid steam-exploded corn straw, which increased the conversion up to 82.6%. The mechanism analysis showed that PEG could effectively reduce the unproductive adsorption of enzyme on the ASCS. The addition of PEG could increase the soluble protein, filter paper activity (FPA), and β-glucosidase activity (β-GA) in the supernatant by 15.0%, 112.5% and 24.8%, respectively. The FT-IR analysis showed that the crystal form of ASCS was cellulose Ⅱcrystal structure. The SEM images showed the addition of PEG caused the collapsing of cellulose structure and the residue appeared as irregular bulk.