Improving ethanol production and viability of Saccharomyces cerevisiae by a vitamin feeding strategy during fed-batch process.
Several bottlenecks in the alcoholic fermentation process must be overcome to reach a very high and competitive performance of bioethanol production by the yeast Saccharomyces cerevisiae. In this paper, a nutritional strategy is described that allowed S. cerevisiae to produce a final ethanol titre of 19% (v/v) ethanol in 45 h in a fed-batch culture at 30 degrees C. This performance was achieved by implementing exponential feeding of vitamins throughout the fermentation process. In comparison to an initial addition of a vitamin cocktail, an increase in the amount of vitamins and an exponential vitamin feeding strategy improved the final ethanol titre from 126 g l(-1) to 135 g l(-1) and 147 g l(-1), respectively. A maximum instantaneous productivity of 9.5 g l(-1) h(-1) was reached in the best fermentation. These performances resulted from improvements in growth, the specific ethanol production rate, and the concentration of viable cells in response to the nutritional strategy.
Alfenore
S
S
Biotechnology and Bioprocess Laboratory, UMR-CNRS 5504, UMR-INRA 792, Institut National des Sciences Appliquées, Département de Génie Biochimique et Alimentaire, Avenue de Rangueil, 31077 Toulouse Cedex, France.
Molina-Jouve
C
C
Guillouet
S E
SE
Uribelarrea
J-L
JL
Goma
G
G
Benbadis
L
L
D018533:Biomass; D003470:Culture Media / Q000378:metabolism; D000431:Ethanol / Q000378:metabolism*; D005285:Fermentation; D005947:Glucose / Q000378:metabolism*; D007218:Industrial Microbiology / Q000379:methods; D007700:Kinetics; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000378:metabolism*; D013194:Staining and Labeling; D014815:Vitamins / Q000494:pharmacology*
D003470:Culture Media; D014815:Vitamins; D000431:Ethanol; D005947:Glucose