Table 3 Based on supplementation with 5.0-g/L butyric acid, the effects of increasing the butyric acid concentration (6.5, 8.5 and 11.5 g/L) on the ABE fermentation parameters from the substrate, the butanol productivity, and the maximal specific growth rates for C. acetobutylicum ATCC 824 and mutant strains were determined as shown below.
Bacterium | Butanol productivity (g/L/h) | Butanol yield (g/g) | Solvents (ABE) yield (g/g) | Acetone yield (g/g) | Ethanol yield (g/g) | Maximal specific growth rate (added butyrate 5.0 g/L) μMax (1/h) | Maximal specific growth rate (added butyrate 6.5 g/L) μMax (1/h) | Maximal specific growth rate (added butyrate 8.5 g/L) μMax (1/h) | Maximal specific growth rate (added butyrate 11.5 g/L) μMax (1/h) |
|---|---|---|---|---|---|---|---|---|---|
C. acetobutylicum ATCC 824 | 0.022 | 0.183 | 0.235 | 0.076 | 0.024 | 0.183 | 0.087 | 0.069 | — |
Mutant FS-JWS-SN-79-6 | 0.068 | 0.418 | 0.494 | 0.113 | 0.060 | 0.224 | 0.146 | 0.093 | 0.057 |
Mutant FS-SXT-AP-R631 | 0.070 | 0.401 | 0.528 | 0.117 | 0.126 | 0.247 | 0.159 | 0.108 | 0.032 |
Mutant FS-SXT-LE-BH-A7 | 0.073 | 0.405 | 0.53 | 0.118 | 0.128 | 0.240 | 0.157 | 0.111 | 0.041 |
Mutant FS-SXT-GC-V9-77 | 0.068 | 0.435 | 0.533 | 0.113 | 0.117 | 0.243 | 0.157 | 0.110 | 0.029 |
Mutant FS-ZKS-TF-MT18 | 0.072 | 0.435 | 0.524 | 0.113 | 0.091 | 0.241 | 0.152 | 0.113 | 0.036 |
Mutant FS-ZKS -TF-ZT637 | 0.067 | 0.426 | 0.532 | 0.109 | 0.101 | 0.245 | 0.147 | 0.112 | 0.038 |
