Table 7.
Application of cell retention for continuous solvent production with solventogenic and acetogenic clostridia
| Strain | Continuous system | Dilution rate | Bleed rate | CDW | Substrate | Product | Titer/productivity /yield | References |
|---|---|---|---|---|---|---|---|---|
| C. acetobutylicum ATCC 824 | Membrane cell-recycle reactor | 0.5 h−1 | 0.025 h−1 | 20 g L−1 | Glucose | ABE solvents | 13 g L−1, 6.5 g L−1 h−1 | [222] |
| C. acetobutylicum ATCC 824 | Cell-recycle reactor | 0.35 h−1 | Total cell retention | 125 g L−1 | Glucose | ABE solvents | 4.5 g L−1 h−1, 0.31 g g−1 | [81] |
| Butanol | 3.7 g L−1 h−1 | |||||||
| C. acetobutylicum ATCC 824 | Spin filter perfusion bioreactor | 0.089 h−1 | Total cell retention | 49 g L−l | Glucose | ABE solvents | 1.14 g L−1 h−1 | [204] |
| C. acetobutylicum AvapClo™ (ATCC 824 with ADH gene) | Membrane cell-recycle reactor with product recovery of the permeate and effluent recirculation | 0.77 h–1 | Bleed for constant CDW | Max 50 g L−1 | C6 lignocellulosic sugars from pine wood | Butanol, acetone, isopropanol and ethanol mix | 10 g L−1 h−1, 0.33 g g−1 sugars | [283] |
| C. acetobutylicum BKM19 | Membrane cell-recycle reactor | 0.86 h−1 | 0.04 h−1 | (OD600nm 335) | Glucose | ABE solvents | 23.5 g L−1, 21.1 g L−1 h−1, 0.34 g g−1 | [125] |
| Butanol | 11.9 g L−1, 10.7 g L−1 h−1, 0.17 g g−1 | |||||||
| C. acetobutylicum CAB1060 | Cell-recycle reactor with in situ extraction and P-limitation | 0.076 h–1 | 0.05 h−1 | 28–30 g L−1 | Glucose | Butanol | 550 g L−1, 14 g L−1 h−1, 0.35 g g−1 | [210] |
| C. acetobutylicum P262 | Membrane cell-recycle reactor | 0.41 h−1 | 0.02 h−1 | 20 g L−1 | Cheese whey permeate | ABE solvents | 0.31 g g−1 | [62] |
| C. acetobutylicum | Cell-recycle reactor with P-limitation | 0.40 h−1 | 13.1 g L−1 | Glucose | Butanol | 4.1 g L−1 h−1 | [257] | |
| C. saccharoperbutyl-acetonicum N1-4 | Membrane cell-recycle reactor | 0.71 h−1 | 0.16 h−1 | 16.3 g L−1 | Glucose | ABE solvents | 8.66 g L−1, 7.54 g L−1 h−1 | [287] |
| C. saccharoperbutyl-acetonicum N1-4 | Membrane cell-recycle reactor | 0.78 h−1 | 17.4 g L−1 | Xylose | Butanol | 4.26 g L−1, 3.32 g L−1 h−1 | [338] | |
| C. autoethanogenum DSM10061 | Membrane cell-recycle reactor | 4.9 day−1 | 0.5 day−1 | 1.83 g L−1 | 65% H2, 23% CO2, 9%N2 | Ethanol | 6.3 g L−1, 0.14 M | [198] |
| C. ljungdahlii ∆SADH (pTCtA) | Cell-recycle reactor | 3–6 mL min−1 | Bleed for constant CDW | 10–18 g L−1 | Fructose | Acetone | 10.8 g L−1 | [134] |
| Co-culture: C. ljungdahlii PETC and C. kluyveri DSM555 | Membrane cell-recycle reactor | 40–80 mL h−1 | 10–20 mL h−1 | (OD600nm 5–10) | Syngas: 60% CO, 35%H2, 5% CO2 | Ethanol | 65.5 mmol CL−1 day−1 | [248] |
| Butanol | 39.2 mmol CL−1 day−1 | |||||||
| Hexanol | 31.7 mmol CL−1 day−1 | |||||||
| C. pasteurianum MBEL_GLY2 | Cell-recycle reactor | 0.90 h−1 | Total cell retention | (OD600nm 407.6) | Glycerol | Total solvents | 9.2 g L−1, 8.3 g L−1 h−1 | [187] |
| Butanol | 8.6 g L−1, 7.8 g L−1 h−1 |
The table focuses on cell recycling systems and shows the essential settings of dilution rate and bleed rate, deployed to achieve high cell dry weight (CDW)