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Table 2 Results for fermentation using Escherichia coli KO11, Zymomonas mobilis mobilis AX101 and Saccharomyces cerevisiae 424A(LNH-ST) in 2% w/w corn steep liquor (CSL) or yeast extract peptone (YEP)

From: Comparing the fermentation performance of Escherichia coli KO11, Saccharomyces cerevisiae 424A(LNH-ST) and Zymomonas mobilis AX101 for cellulosic ethanol production

Nutrients Source/sugar Type Concentration (g/L) Strain Sugar consumption (%)* Metabolic EtOH yield (%)*† Carbon balance coverage‡ EtOH Concentration* Volumetric productivity (g/L/hr)† Specific productivity (g/L/h/g cell)0--48 h
        Glc 0-24 h Xyl 0-48 h EtOH 0-48 h  
   KO11 100.0 ± 0.0 87.0 ± 0.9 97.3 ± 1.1 44.3 ± 0.5 -2.37 ± 0.00 N/A 0.79 0.57 ± 0.03
CSL/glucose 100 AX101 100.0 ± 0.0 93.2 ± 0.1 95.1 ± 0.1 47.5 ± 0.1 -3.64 ± 0.13 N/A 0.97 0.77 ± 0.07
   424A(LHN-ST) 100.0 ± 0.0 85.2 ± 0.5 95.8 ± 0.4 43.5 ± 0.3 -4.16 ± 0.03 N/A 0.87 0.16 ± 0.00
   KO11 98.2 ± 0.5 85.1 ± 1.1 95.9 ± 1.1 41.9 ± 0.8 -2.16 ± 0.07 -0.38 ± 0.03 +0.72 ± 0.01 0.55 ± 0.00
CSL/glucose + xylose 70 + 30 AX101 94.5 ± 2.4 88.6 ± 0.0 96.0 ± 0.0 41.5 ± 1.1 -2.43 ± 0.37 -0.29 ± 0.05 +0.77 ± 0.02 0.69 ± 0.02
   424A(LHN-ST) 98.4 ± 0.5 82.4 ± 0.5 100.3 ± 0.5 40.2 ± 0.1 -2.76 ± 0.08 -0.39 ± 0.04 +0.73 ± 0.01 0.13 ± 0.00
   KO11 100.0 ± 0.0 85.1 ± 0.0 93.6 ± 0.2 43.1 ± 0.1 N/A -1.74 ± 0.02 +0.72 ± 0.01 0.54 ± 0.00
CSL/Xylose 100 AX101 95.3 ± 0.1 84.9 ± 0.2 97.1 ± 0.1 41.3 ± 0.1 N/A -1.04 ± 0.01 +0.42 ± 0.00 0.46 ± 0.01
   424A(LHN-ST) 37.9 ± 6.5 89.8 ± 1.3 93.2 ± 0.9 18.1 ± 3.2 N/A -0.32 ± 0.05 +0.09 ± 0.02 0.10 ± 0.00
YEP§/xylose 100 424A(LHN-ST) 100.0 ± 0.0 92.0 ± 0.01 N/A 46.9 ± 0.0 N/A -1.77 ± 0.02 +0.87 ± 0.01 0.11 ± 0.00
  1. *Time-span for the calculated data: Glc fermentation 0-72 h; Xyl and co-fermentation 0-168 h.
  2. The method to calculate metabolic yields and productivities were as reported in Ref [24].
  3. Carbon balance covers ethanol, carbon dioxide and all the selected by-products formed during fermentation relative to carbon in consumed sugars. Carbon dioxide production was estimated through the stoichiometric equation for the fermentation of glucose to ethanol - ethanol and carbon dioxide were produced on an equimolar basis.
  4. §Yeast extract peptone (YEP), 10 g/L bacto yeast extract +20 g/L bacto peptone.
  5. CSL, corn steep liquor; NA, not applicable.