Table 6 Metabolite analysis of culture broths of the K. pneumoniae Δ(ldhA als) mutant by repeated fed-batch fermentation at intervals of 24 h using crude glycerol as a substrate under different pH conditions
Cycle no. | 1,3-PDO (g/L) | 2,3-BDO (g/L) | Ethanol (g/L) | Acetate (g/L) | Succinate (g/L) | 1,3-PDO productivity (g/L/h) | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
pH | 6.0 | 6.5 | 7.0 | 6.0 | 6.5 | 7.0 | 6.0 | 6.5 | 7.0 | 6.0 | 6.5 | 7.0 | 6.0 | 6.5 | 7.0 | 6.0 | 6.5 | 7.0 |
1 | 49.9 | 53.5 | 45.5 | 10.1 | 11.1 | 9.5 | 4.1 | 7.5 | 8.9 | 6.0 | 5.0 | 4.0 | 3.89 | 6.47 | 7.87 | 2.08 | 2.23 | 1.90 |
2 | 49.4 | 54.2 | 49.8 | 11.2 | 11.3 | 11.6 | 3.9 | 5.7 | 10.4 | 4.9 | 4.6 | 4.4 | 3.29 | 6.04 | 7.34 | 2.06 | 2.26 | 2.08 |
3 | 49.7 | 57.7 | 44.6 | 10.5 | 12.7 | 10.7 | 4.8 | 7.8 | 10.6 | 6.3 | 5.4 | 3.2 | 3.36 | 6.59 | 7.92 | 2.07 | 2.40 | 1.86 |
4 | 47.4 | 54.4 | 48.1 | 8.1 | 11.8 | 10.4 | 2.4 | 6.2 | 7.5 | 5.7 | 5.0 | 3.0 | 3.65 | 5.99 | 7.39 | 1.98 | 2.27 | 2.00 |