title: The role of 1,3-propanediol production in fermentation of glycerol by Clostridium pasteurianum.
abstract: Waste crude glycerol from biodiesel production can be used to produce biobutanol using Clostridium pasteurianum with the main products being n-butanol, 1,3-propanediol (PDO) and ethanol. There has been much discrepancy and mystery around the cause and effect of process parameters on the product distribution, thus a better understanding of the pathway regulation is required. This study shows that as process pH decreased, the rate of cell growth and CO2 production also decreased, resulting in slower fermentations, increased duration of butanol production and higher butanol concentrations and yields. The production rate of PDO was multi-modal and the role of PDO appears to function in redox homeostasis. The results also showed that C. pasteurianum displayed little biphasic behavior when compared to Clostridia spp. typically used in ABE fermentation due to the alternative glycolysis-independent reductive pathway of PDO production, rendering it suitable for a continuous fermentation process.
authors.affiliation: Department of Chemical & Biochemical Engineering, The University of Western Ontario, 1151 Richmond St., London, Ontario N6A 3K7, Canada.
authors.forename: Erin E
authors.initials: EE
authors.lastname: Johnson
authors.affiliation: Department of Chemical & Biochemical Engineering, The University of Western Ontario, 1151 Richmond St., London, Ontario N6A 3K7, Canada; Department of Biochemical Engineering, AVT - Aachener Verfahrenstechnik, RWTH Aachen University, Worringer Weg 1, 52074 Aachen, Germany. Electronic address: lrehmann@uwo.ca.
authors.forename: Lars
authors.initials: L
authors.lastname: Rehmann
mesh_terms: D020001:1-Butanol / Q000378:metabolism; D056804:Biofuels; D000440:Butanols / Q000378:metabolism; D003013:Clostridium / Q000378:metabolism*; D000431:Ethanol / Q000378:metabolism; D005285:Fermentation; D005990:Glycerol / Q000378:metabolism*; D011409:Propylene Glycols / Q000378:metabolism*
chemical_list: D056804:Biofuels; D000440:Butanols; D011409:Propylene Glycols; D000431:Ethanol; C041787:1,3-propanediol; D020001:1-Butanol; D005990:Glycerol
keywords: Biorefinery; Butanol; Fermentation; Online measurements; Redox