Sulphite addition during steam pretreatment enhanced both enzyme-mediated cellulose hydrolysis and ethanol production

Na Zhong, Richard Chandra*, Minna Yamamoto, Timo Leskinen, Tom Granström, Jack Saddler*

*Corresponding author for this work

Research output: Contribution to journalArticleScientificpeer-review

6 Citations (Scopus)

Abstract

Sulphite addition during steam pretreatment of softwoods under acidic, neutral and alkaline conditions was assessed to try to minimize lignin condensation. Although pretreatment under neutral/alkaline conditions resulted in effective lignin sulphonation, non-uniform size reduction was observed. In contrast, acidic sulphite steam treatment at 210 °C for 10 min resulted in homogenous particle size reduction and water-insoluble component that was 62% carbohydrate and 33% lignin. This carbohydrate-rich substrate was readily hydrolyzed and fermented which indicated the lack of fermentation inhibitors in the steam-pretreated whole slurry. The use of high solid loading (25% w/v) resulted in a hydrolysis yield of 58% at an enzyme loading of 40 mg protein/g glucan and efficient fermentation (46.6 g/L of ethanol). This indicated that the addition of acidic sulphite at the steam pretreatment of softwoods improved both the enzymatic hydrolysis and fermentation of steam-pretreated whole slurries.

Original languageEnglish
Article number71
JournalBioresources and Bioprocessing
Volume9
Issue number1
DOIs
Publication statusPublished - 29 Jun 2022
MoE publication typeA1 Journal article-refereed

Funding

The authors wish to thank China Scholarship Council and Mitacs for funding this research. We acknowledge Novozymes for their generous gift of cellulase enzymes mixtures.

Keywords

  • Acid steam pretreatment
  • Detoxification
  • Fermentation
  • High consistency hydrolysis
  • Sulphite steam pretreatment
  • Whole slurry

Fingerprint

Dive into the research topics of 'Sulphite addition during steam pretreatment enhanced both enzyme-mediated cellulose hydrolysis and ethanol production'. Together they form a unique fingerprint.

Cite this