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Table 1 Fermentation characteristics for Saccharomyces cerevisiae CEN.PK113-7D and the two mutant strains during anaerobic fed-batch fermentation at 30°C

From: The metabolic costs of improving ethanol yield by reducing glycerol formation capacity under anaerobic conditions in Saccharomyces cerevisiae

  WT TEFmut7 TEFmut2
Fermentation time (h) 70 146 167
Growth time (h) 24 60 133
μmax (h-1) 0.29 ± 0.01 0.13 ± 0.01 0.046 ± 0.001
DCWmax (g L-1) 12.0 ± 0.5 8.0 ± 0.5 3.8 ± 0.2
Y DCW/glucose g g-1 0.076 ± 0.001 0.074 ± 0.003 0.055 ± 0.001
[0–16 h] [0–30 h] [0–44 h]
Y glycerol/glucose g g-1 0.056 ± 0.001 0.031 ± 0.003 0.022 ± 0.004
[0–16 h] [0–30 h] [0–44 h]
Y glycerol/DCW g g-1 0.74 ± 0.03 0.42 ± 0.02 0.40 ± 0.04
[0–16 h] [0–30 h] [0–44 h]
Y acetate/ glucose g g-1 0.005 ± 0.001 n.d. n.d.
Y pyruvate/ glucose g g-1 0.003 ± 0.001 n.d. n.d.
Y succinate/ glucose g g-1 0.004 ± 0.001 0.013 ± 0.001 0.026 ± 0.001
Yethanol/glucose g g-1 (growth) 0.45 ± 0.003 0.46 ± 0.008 0.48 ± 0.005
Yethanol/glucose g g-1 (overall) 0.47 ± 0.001 0.48 ± 0.003 0.48 ± 0.005
[ethanol] final (g L-1) 139 ± 1 106.0 ± 0.5 57 ± 2
[glycerol] final (g L-1) 9.0 ± 0.3 5.4 ± 0.1 2.8 ± 0.2
Ethanol productivity (g L-1 h-1) 1.97 ± 0.10 0.73 ± 0.03 0.33 ± 0.02
Pcritical (g L-1) 90 ± 2 78 ± 1 54 ± 2
  1. μmax: maximum specific growth rate, DCWmax maximum cell concentration , Yi/j yield of production of constituent i on the constituent j: DCW biomass ;.n.d. : not detected (detection thresholds were 60, 50 and 100 mg L-1 for acetate, pyruvate and succinate respectively). Yields, concentrations, and specific rates are average values of 2 independent fermentations. Productivity and fermentation time correspond to the experiments shown in the paper.