Applied Biochemistry and Biotechnology

, Volume 146, Issue 1, pp 231–248

Non-ionic Surfactants and Non-Catalytic Protein Treatment on Enzymatic Hydrolysis of Pretreated Creeping Wild Ryegrass

  • Yi Zheng
  • Zhongli Pan
  • Ruihong Zhang
  • Donghai Wang
  • Bryan Jenkins

DOI: 10.1007/s12010-007-8035-9

Cite this article as:
Zheng, Y., Pan, Z., Zhang, R. et al. Appl Biochem Biotechnol (2008) 146: 231. doi:10.1007/s12010-007-8035-9


Our previous research has shown that saline Creeping Wild Ryegrass (CWR), Leymus triticoides, has a great potential to be used for bioethanol production because of its high fermentable sugar yield, up to 85% cellulose conversion of pretreated CWR. However, the high cost of enzyme is still one of the obstacles making large-scale lignocellulosic bioethanol production economically difficult. It is desirable to use reduced enzyme loading to produce fermentable sugars with high yield and low cost. To reduce the enzyme loading, the effect of addition of non-ionic surfactants and non-catalytic protein on the enzymatic hydrolysis of pretreated CWR was investigated in this study. Tween 20, Tween 80, and bovine serum albumin (BSA) were used as additives to improve the enzymatic hydrolysis of dilute sulfuric-acid-pretreated CWR. Under the loading of 0.1 g additives/g dry solid, Tween 20 was the most effective additive, followed by Tween 80 and BSA. With the addition of Tween 20 mixed with cellulase loading of 15 FPU/g cellulose, the cellulose conversion increased 14% (from 75 to 89%), which was similar to that with cellulase loading of 30 FPU/g cellulose and without additive addition. The results of cellulase and BSA adsorption on the Avicel PH101, pretreated CWR, and lignaceous residue of pretreated CWR support the theory that the primary mechanism behind the additives is prevention of non-productive adsorption of enzymes on lignaceous material of pretreated CWR. The addition of additives could be a promising technology to improve the enzymatic hydrolysis by reducing the enzyme activity loss caused by non-productive adsorption.


Saline Creeping Wild RyegrassCellulase β-GlucosidaseTween 20Tween 80Bovine serum albuminEnzymatic hydrolysisAvicel PH101Lignaceous residue



Creeping Wild Ryegrass, Leymus triticoides


bovine serum albumin


cellulase activity


β-glucosidase activity

Tween 80


Tween 20



simultaneous saccharification and fermentation

DI water

deionized water


high-performance liquid chromatography

Copyright information

© Humana Press Inc. 2007

Authors and Affiliations

  • Yi Zheng
    • 1
  • Zhongli Pan
    • 1
    • 2
  • Ruihong Zhang
    • 1
  • Donghai Wang
    • 3
  • Bryan Jenkins
    • 1
  1. 1.Biological and Agricultural Engineering DepartmentUniversity of California, DavisDavisUSA
  2. 2.Processed Foods Research UnitUSDA–ARS–WRRCSt. AlbanyUSA
  3. 3.Biological and Agricultural Engineering DepartmentKansas State UniversityManhattanUSA