AIMS Bioengineering, 2016, 3(4): 441-453. doi: 10.3934/bioeng.2016.4.441

Research article

Export file:

Format

  • RIS(for EndNote,Reference Manager,ProCite)
  • BibTex
  • Text

Content

  • Citation Only
  • Citation and Abstract

The effects of ethanol on hydrolysis of cellulose and pretreated barley straw by some commercial cellulolytic enzyme products

1 Eastern Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, Wyndmoor, Pennsylvania, 19038, USA
2 National Institute of Food and Agriculture, U.S. Department of Agriculture, Washington, District of Columbia, 20024, USA
3 DuPont Engineering Research and Technology, Wilmington, Delaware, 19803, USA

The effect of ethanol at levels ranging from 2.5% v/v to 15% v/v on the activities of two recently developed commercial cellulosic biomass hydrolytic enzyme products, Accellerase® 1500 and Accellerase® XY, was investigated. The substrates used for study of the effect of ethanol on Accellerase® 1500 included α-cellulose, cellobiose and barley straw pretreated by the soaking in aqueous ammonia method. The initial rates of glucose production and final glucose concentrations obtained at 48 h of hydrolysis were used as the response factors. To study the effect of ethanol on Accellerase® XY, beechwood xylan and the pretreated barley straw were used as substrates. The response factors included the initial rates of xylose production and final xylose concentrations obtained at 48 h of hydrolysis. It was found that ethanol acted as either activator or inhibitor depending on its concentration and the type of substrate used. At 10% v/v, which is expected to be the final concentration of ethanol in a commercial cellulosic biomass-based process, ethanol acted as an inhibitor in all cases. However, even at this ethanol level, both commercial enzymes still retained at least about 50% of their activities.
  Figure/Table
  Supplementary
  Article Metrics

References

1. Drapcho C, Nghiem N, Walker T (2008) Ethanol, In: Biofuels Engineering Process Technology, 1 Ed., New York: Mc-Graw-Hill, 105–195.

2. Gottschalk G (1986) Catabolic activities of aerobic heterotrophs, In: Bacterial Metabolism, 2Eds., New York: Springer-Verlag, 141–177.

3. Holtzapple M, Cognata M, Shu Y, et al. (1990) Inhibition of Trichoderma reesei cellulase by sugars and solvents. Biotechnol Bioeng 36: 275–287.    

4. Bezerra R and Dias A (2005) Enzymatic kinetics of cellulose hydrolysis—Inhibition by ethanol and cellobiose. Appl Biochem Biotechol 126: 49–59.    

5. Bezerra R, Dias A, Fraga I, et al. (2006) Simultaneous ethanol and cellobiose inhibition of cellulose hydrolysis studied with integrated equations assuming constant or variable substrate concentrations. Appl Biochem Biotechnol 134: 27–37.    

6. Wu Z, Lee Y (1997) Inhibition of the enzymatic hydrolysis of cellulose by ethanol. Biotechnol Letters 19: 977–979.    

7. Ghosh P, Pamment N, Martin W (1982) Simultaneous saccharification and fermentation of cellulose: effect of b-D-glucosidase activity and ethanol inhibition of cellulases. Enzyme Microb Technol 4: 425–430.    

8. Jing X, Zhang X, Bao J (2009) Inhibition performance of lignocellulose degradation products on industrial cellulase enzymes during cellulose hydrolysis. Appl Biochem Biotechnol 159: 696–707.    

9. Szczodrak J, Targonski Z (1989) Simultaneous saccharification and fermentation of cellulose: Effect of ethanol and cellulases on particular stages. Acta Biotechnol 6: 555–564.

10. Takagi M (1984) Inhibition by cellulase by fermentation products. Biotechnol Bioeng 26: 1506–1507.    

11. Ooshima H, Ishitani Y, Harano Y (1985) Simultaneous saccharification and fermentation of cellulose: Effect of ethanol on enzymatic saccharification of cellulose. Biotechnol Bioeng 27: 389–397.    

12. Chen H and Jin S (2006) Effect of ethanol and yeast on cellulase activity and hydrolysis of crystalline cellulose. Enzyme Microb Technol 39: 1430–1432.    

13. Hoyer K, Galbe M, Zacchi G (2008) Production of fuel ethanol from softwood by simultaneous saccharification and fermentation at high dry matter content. J Chem Technol Biotechnol 84: 570–577.

14. Nonaka H, Hideno A (2014) Quantification of cellulose adsorbed on saccharification residue without the use of colorimetric protein assays. J Mol Cat B: Enzymatic 110: 54–58.    

15. Nghiem N, Kim T, Yoo C, et al. (2013) Enzymatic fractionation of SAA-pretreated barley straw for production of fuel ethanol and astaxanthin as a value-added co-product. Appl Biochem Biotechnol 171: 341–351.    

16. Sluiter A, Hames B, Ruiz R, et al. (2008) Determination of structural carbohydrates and lignin in biomass. Lab Anal Proced 1617.

Copyright Info: © 2016, Nhuan P. Nghiem, et al., licensee AIMS Press. This is an open access article distributed under the terms of the Creative Commons Attribution Licese (http://creativecommons.org/licenses/by/4.0)

Download full text in PDF

Export Citation

Article outline

Show full outline
Copyright © AIMS Press All Rights Reserved