MULTI-STAGE ENZYMATIC HYDROLYSIS TO INVESTIGATE THE FACTORS AFFECTING THE KINETICS OF ENZYMATIC HYDROLYSIS OF CELLULOSE
In enzymatic hydrolysis (EH) of biomass, the rate of saccharification decreases with time and it becomes difficult to convert all carbohydrates to fermentable sugars. Previous research suggests that the rate reduction is related to substrate reactivity, enzyme activity, and end product inhibition. In this work, both single and multi-stage EH were conducted to investigate these effects. Cellulose Avicel PH-101 was used as substrate for EH. The total 96 hour, eight-stage EH converted 86.8％ and 93.7％ glucan, while single-stage EH barely obtained 51.3％ and 68.1％ glucan conversion with 5 and 20 FPU/g substrate enzyme loading, respectively, In multi-stage EH of Avicel, the reactivity decreased by 16％ after the eight stages of EH, which was most likely due to the retained enzymes that may block some active sites of Avicel. The crystallinity had no change, indicating that the structure of Avicel also had minimum changes. The impact of end-product inhibition on EH was investigated by comparing multi-stage EH with and without glucose addition. Without the interference of enzymes deactivation, glucose had an impact at 5 FPU/g substrate enzyme loading, but no impact at 20 FPU/g substrate enzyme loading. A 25％ difference between eight-stage and 96h EH kinetics of Avicel showed that the enzymes deactivation and decline of substrate reactivity are the most important factors affecting EH kinetics. End-product inhibition became pronounced at low enzyme loading.
multi-stage enzymatic hydrolysis kinetics of enzymatic hydrolysis substrate reactivity enzymes deactivation end-product inhibition
Zhiying Yu Hasan Jameel Hou-min Chang Richard Philips Sunkyu Park
Department of Forest Biomaterials, North Carolina State University, Raleigh, NC 27695-8005, USA
国际会议
16th International Symposium on Wood,Fiber and Pulping Chemistry(第十六届木材、纤维及制浆化学国际会议)
天津
英文
1083-1088
2011-06-08（万方平台首次上网日期，不代表论文的发表时间）