Applied Biochemistry and Biotechnology

, Volume 104, Issue 1, pp 37–50

Pretreatment of corn stover using wet oxidation to enhance enzymatic digestibility

  • Enikő Varga
  • Anette S. Schmidt
  • Kati Réczey
  • Anne Belinda Thomsen
Article

DOI: 10.1385/ABAB:104:1:37

Cite this article as:
Varga, E., Schmidt, A.S., Réczey, K. et al. Appl Biochem Biotechnol (2003) 104: 37. doi:10.1385/ABAB:104:1:37

Abstract

Corn stover is an abundant, promising raw material for fuel ethanol production. Although it has a high cellulose content, without pretreatment it resists enzymatic hydrolysis, like most lignocellulosic materials. Wet oxidation (water, oxygen, mild alkali or acid, elevated temperature and pressure) was investigated to enhance the enzymatic digestibility of corn stover. Six different combinations of reaction temperature, time, and pH were applied. The best conditions (60g/L of corn stover, 195°C, 15 min, 12 bar O2, 2 g/L of Na2CO3) increased the enzymatic conversion of corn stover four times, compared to untreated material. Under these conditions 60% of hemicellulose and 30% of lignin were solubilized, whereas 90% of cellulose remained in the solid fraction. After 24-h hydrolysis at 50°C using 25 filter paper units (FPU)/g of dry matter (DM) biomass, the achieved conversion of cellulose to glucose was about 85%. Decreasing the hydrolysis temperature to 40°C increased hydrolysis time from 24 to 72 h. Decreasing the enzyme loading to 5 FPU/g of DM biomass slightly decreased the enzymatic conversion from 83.4 to 71%. Thus, enzyme loading can be reduced without significantly affecting the efficiency of hydrolysis, an important economical aspect.

Index Entries

Corn stoverwet oxidationslurryfilter cakesenzymatic convertible celluloseenzymatic digestibility

Copyright information

© Humana Press Inc. 2003

Authors and Affiliations

  • Enikő Varga
    • 1
  • Anette S. Schmidt
    • 3
  • Kati Réczey
    • 1
  • Anne Belinda Thomsen
    • 2
  1. 1.Department of Agricultural Chemical TechnologyBudapest University of Technology and EconomicsBudapestHungary
  2. 2.Riso National LaboratoryPlant Research DepartmentRoskildeDenmark
  3. 3.Protein ChemistryNovo Nordisk A/SGentofteDenmark