title: Consolidated bioprocessing of untreated switchgrass to hydrogen by the extreme thermophile Caldicellulosiruptor saccharolyticus DSM 8903.
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.
authors.affiliation: Center for Bioprocessing Research and Development, South Dakota School of Mines and Technology, Rapid City, SD 57701, USA.
authors.forename: Suvarna
authors.initials: S
authors.lastname: Talluri
authors.forename: Subramanian Mohan
authors.initials: SM
authors.lastname: Raj
authors.forename: Lew Paul
authors.initials: LP
authors.lastname: Christopher
mesh_terms: D000693:Anaerobiosis / Q000187:drug effects; D001709:Biotechnology / Q000379:methods*; D002244:Carbon / Q000378:metabolism; D002245:Carbon Dioxide / Q000378:metabolism; D002482:Cellulose / Q000378:metabolism; D005947:Glucose / Q000494:pharmacology; D006094:Gram-Positive Bacteria / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism* / Q000648:ultrastructure; D006859:Hydrogen / Q000378:metabolism*; D008897:Panicum / Q000187:drug effects / Q000378:metabolism*; D011108:Polymers / Q000494:pharmacology; D013696:Temperature; D013997:Time Factors
chemical_list: D011108:Polymers; D002245:Carbon Dioxide; D002244:Carbon; D006859:Hydrogen; D002482:Cellulose; D005947:Glucose