title: Characterization of Electrical Current-Generation Capabilities from Thermophilic Bacterium Thermoanaerobacter pseudethanolicus Using Xylose, Glucose, Cellobiose, or Acetate with Fixed Anode Potentials.
abstract: Thermoanaerobacter pseudethanolicus 39E (ATCC 33223), a thermophilic, Fe(III)-reducing, and fermentative bacterium, was evaluated for its ability to produce current from four electron donors-xylose, glucose, cellobiose, and acetate-with a fixed anode potential (+ 0.042 V vs SHE) in a microbial electrochemical cell (MXC). Under thermophilic conditions (60 °C), T. pseudethanolicus produced high current densities from xylose (5.8 ± 2.4 A m(-2)), glucose (4.3 ± 1.9 A m(-2)), and cellobiose (5.2 ± 1.6 A m(-2)). It produced insignificant current when grown with acetate, but consumed the acetate produced from sugar fermentation to produce electrical current. Low-scan cyclic voltammetry (LSCV) revealed a sigmoidal response with a midpoint potential of -0.17 V vs SHE. Coulombic efficiency (CE) varied by electron donor, with xylose at 34.8% ± 0.7%, glucose at 65.3% ± 1.0%, and cellobiose at 27.7% ± 1.5%. Anode respiration was sustained over a pH range of 5.4-8.3, with higher current densities observed at higher pH values. Scanning electron microscopy showed a well-developed biofilm of T. pseudethanolicus on the anode, and confocal laser scanning microscopy demonstrated a maximum biofilm thickness (Lf) greater than ~150 μm for the glucose-fed biofilm.
authors.affiliation: Swette Center for Environmental Biotechnology, The Biodesign Institute at Arizona State University , P.O. Box 875701, Tempe, Arizona 85287-5701, United States.
authors.forename: Bradley G
authors.initials: BG
authors.lastname: Lusk
authors.affiliation: Swette Center for Environmental Biotechnology, The Biodesign Institute at Arizona State University , P.O. Box 875701, Tempe, Arizona 85287-5701, United States.|Department of Microbiology, Quaid-I-Azam University , Islamabad, 45320, Pakistan.
authors.forename: Qaiser Farid
authors.initials: QF
authors.lastname: Khan
authors.affiliation: Swette Center for Environmental Biotechnology, The Biodesign Institute at Arizona State University , P.O. Box 875701, Tempe, Arizona 85287-5701, United States.
authors.forename: Prathap
authors.initials: P
authors.lastname: Parameswaran
authors.affiliation: Department of Microbiology, Quaid-I-Azam University , Islamabad, 45320, Pakistan.
authors.forename: Abdul
authors.initials: A
authors.lastname: Hameed
authors.affiliation: Department of Microbiology, Quaid-I-Azam University , Islamabad, 45320, Pakistan.
authors.forename: Naeem
authors.initials: N
authors.lastname: Ali
authors.affiliation: Swette Center for Environmental Biotechnology, The Biodesign Institute at Arizona State University , P.O. Box 875701, Tempe, Arizona 85287-5701, United States.
authors.forename: Bruce E
authors.initials: BE
authors.lastname: Rittmann
authors.affiliation: Swette Center for Environmental Biotechnology, The Biodesign Institute at Arizona State University , P.O. Box 875701, Tempe, Arizona 85287-5701, United States.|School for Engineering of Matter, Transport and Energy, Arizona State University , 501 E Tyler Mall, Tempe, Arizona 85287, United States.
authors.forename: Cesar I
authors.initials: CI
authors.lastname: Torres
mesh_terms: D000085:Acetates; D001674:Bioelectric Energy Sources; D018441:Biofilms; D002475:Cellobiose / Q000378:metabolism; D055664:Electrochemical Techniques / Q000295:instrumentation; D004566:Electrodes; D005285:Fermentation; D005947:Glucose / Q000378:metabolism; D008855:Microscopy, Electron, Scanning; D046968:Thermoanaerobacter / Q000737:chemistry / Q000378:metabolism*; D014994:Xylose / Q000378:metabolism
chemical_list: D000085:Acetates; D002475:Cellobiose; D014994:Xylose; D005947:Glucose