Study on the Decreased Sugar Yield in Enzymatic Hydrolysis of Cellulosic Substrate at High Solid Loading |
| |
Authors: | Wei Wang Li Kang Hui Wei Rajeev Arora Y Y Lee |
| |
Institution: | (1) Department of Chemical Engineering, Auburn University, Auburn, AL 36849, USA;(2) Department of Horticulture, and the Interdepartmental Plant Biology Major, Iowa State University, 139 Horticulture Hall, Ames, IA 50011–1100, USA;(3) Present address: National Renewable Energy Laboratory, 1617 Cole Blvd, Golden, CO 80401, USA |
| |
Abstract: | Current technology for conversion of biomass to ethanol is an enzyme-based biochemical process. In bioethanol production,
achieving high sugar yield at high solid loading in enzymatic hydrolysis step is important from both technical and economic
viewpoints. Enzymatic hydrolysis of cellulosic substrates is affected by many parameters, including an unexplained behavior
that the glucan digestibility of substrates by cellulase decreased under high solid loadings. A comprehensive study was conducted
to investigate this phenomenon by using Spezyme CP and Avicel as model cellulase and cellulose substrate, respectively. The
hydrolytic properties of the cellulase under different substrate concentrations at a fixed enzyme-to-substrate ratio were
characterized. The results indicate that decreased sugar yield is neither due to the loss of enzyme activity at a high substrate
concentration nor due to the higher end-product inhibition. The cellulase adsorption kinetics and isotherm studies indicated
that a decline in the binding capacity of cellulase may explain the long-observed but little-understood phenomenon of a lower
substrate digestibility with increased substrate concentration. The mechanism how the enzyme adsorption properties changed
at high substrate concentration was also discussed in the context of exploring the improvement of the cellulase-binding capacity
at high substrate loading. |
| |
Keywords: | |
本文献已被 PubMed SpringerLink 等数据库收录! |
|