Table 2.
Comparison of process parameters during fermentation of Bacillus subtilis DSM 10T employing medium B and C
| Fed-batch | Batch | |
|---|---|---|
| The current study | Willenbacher et al. (2014) | |
| Applied medium | C | B |
| Fermentation approach | Foam fractionation | Foam fractionation |
| Initial glucose conc. | 8 g/L | 40 g/L |
| Addition of glucose | 23 mL of 450 g/L | – |
| Final glucose conc. | 0 g/L | 29.19 g/L |
| Cultivation time (h) | 34 | 30 |
| Max. CDW (g/L) | 3.80 | 2.97 |
| µmax (h−1) | 0.31 | 0.34 |
| Max. cSurfactin foam (g/L) | 3.67 | 3.99 |
| Foam volume (mL) | 435 | 334 |
| Surfactin in foam (g) | 1.02 | 0.74 |
| Overall Surfactin (g) | 1.22 | 0.81 |
| YP/X (g/g) | 0.26 | 0.19 |
| YX/S (g/g) | 0.20 | 0.27 |
| YP/S (g/g) | 0.05 | 0.03 |
| Int. qSurfactin [g/(g h)] | 0.009 | 0.006 |
| Int. vol. qSurfactin [g/(L h)] | 0.022 | 0.017 |
| Overall Surfactin recovery (%) | 83.81 | 91.96 |
| Max. Surfactin enrichment | 27.10 | 101.92 |
| Mean bacterial enrichment | 0.41 | 1.60 |
The approach and results of B. subtilis DSM 10T batch fermentation (Willenbacher et al. 2014) is compared to data collected during fed-batch fermentation of B. subtilis DSM 10T employing the further optimized medium C