TABLE 4.
Profiles of biomass, consumed glucose, end products, succinate yield, and volumetric productivity in strain ES04/PCK+PYC under pH-controlled batch culture conditionsa
| Controlled pHb | Biomass (g [DCW]/liter)c | Consumed glucose (g/liter) | End product (g/liter) |
Succinate yield (% [g/g])d | Volumetric productivity (g/liter/h)e | |||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Pyruvate | Malate | Formate | Succinate | Lactate | Acetate | Ethanol | 2,3-Butanediol | |||||
| 7.0 | 1.5 ± 0.1 | 40.5 ± 1.1 | 5.1 ± 0.3 | 5.4 ± 0.5 | 1.0 ± 0.1 | 22.6 ± 1.2 | 0.3 ± 0.1 | 1.1 ± 0.4 | 0.2 ± 0.1 | <0.1 | 55.8 ± 3.8 | 0.47 ± 0.02 |
| 5.7 | 1.3 ± 0.1 | 15.4 ± 1.2 | 0.3 ± 0.1 | 0.3 ± 0.1 | 0.1 ± 0.1 | 11.2 ± 1.4 | 0.1 ± 0.1 | 0.5 ± 0.1 | <0.1 | <0.1 | 72.7 ± 3.6 | 0.23 ± 0.03 |
| 5.5 | 1.2 ± 0.1 | 7.2 ± 0.4 | 0.5 ± 0.1 | 0.2 ± 0.1 | <0.1 | 5.1 ± 0.2 | 0.1 ± 0.1 | 0.4 ± 0.1 | <0.1 | <0.1 | 70.8 ± 0.5 | 0.11 ± 0.01 |
a
Data are expressed as means ± SD from three independent experiments.
b
pH was maintained at 7.0, 5.7, and 5.5 by 2 N NaOH.
c
Initial biomass was adjusted to 1.2 g (DCW)/liter.
d
Succinate yield is gram of product per gram of consumed glucose expressed as a percentage.
e
Volumetric productivity indicates the succinate titer (g/liter/h).