Consolidated bioprocessing of untreated switchgrass to hydrogen by the extreme thermophile Caldicellulosiruptor saccharolyticus DSM 8903

Bioresour Technol. 2013 Jul:139:272-9. doi: 10.1016/j.biortech.2013.04.005. Epub 2013 Apr 18.

Abstract

The abilities of the extreme thermophilic bacterium Caldicellulosiruptor saccharolyticus DSM 8903 to ferment switchgrass (SWG), microcrystalline cellulose (MCC) and glucose to hydrogen (H2) in one-step were examined. Hydrogen production from glucose reached the theoretical maximum for dark fermentation of 4 mol H2/mol glucose. The H2 yield on MCC and SWG after 6 days of fermentation was 23.2 mmol H2/L or 9.4 mmol H2/g MCC and 14.3 mmol H2/L or 11.2 mmol H2/g SWG, respectively. The rate of H2 formation however was higher on MCC (0.7 mmol/Lh) than SWG (0.1 mmol/Lh). C. saccharolyticus DSM 8903 was able to produce H2 directly from mechanically-comminuted SWG without any physicochemical or biological pretreatment. Combining four processing steps (pretreatment, enzyme production, saccharification and fermentation) into a single biorefinery operation makes C. saccharolyticus DSM 8903 a promising candidate for consolidated bioprocessing (CBP) of lignocellulosic biomass.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Anaerobiosis / drug effects
  • Biotechnology / methods*
  • Carbon / metabolism
  • Carbon Dioxide / metabolism
  • Cellulose / metabolism
  • Glucose / pharmacology
  • Gram-Positive Bacteria / drug effects
  • Gram-Positive Bacteria / growth & development
  • Gram-Positive Bacteria / metabolism*
  • Gram-Positive Bacteria / ultrastructure
  • Hydrogen / metabolism*
  • Panicum / drug effects
  • Panicum / metabolism*
  • Polymers / pharmacology
  • Temperature*
  • Time Factors

Substances

  • Polymers
  • Carbon Dioxide
  • Carbon
  • Hydrogen
  • Cellulose
  • Glucose