Table 1.
Maximal concentrations of measured fermentation products by each inocula tested.
| Inoculum | In. pH | In. O2 | Fermentation products [mM]max |
||||
|---|---|---|---|---|---|---|---|
| EtOH | BuOH | Acetic | Butyric | Propionic | |||
| C. faeces | Neutral | - | 15.6 ± 3.2 | 2.28 ± 0.6 | 0.5 ± 0.5 | 31.7 ± 1.2 | 1.3 ± 0.4 |
| + | 18.4 ± 2.3 | 3.8 ± 0.8 | 9.0 ± 0.3 | 28.0 ± 1.4 | 1.2 ± 0.0 | ||
| Acid | - | 21.0 ± 6.5 | ND | 3.4 ± 3.3 | 3.4 ± 0.3 | 1.3 ± 0.7 | |
| + | 22.6 ± 2.8 | 2.8 ± 1.6 | 8.8 ± 1.7 | 5.7 ± 2.8 | ND | ||
| Rumen | Neutral | - | 26.8 ± 3.2 | 1.3 ± 0.7 | 8.9 ± 0.2 | 19.2 ± 1.9 | ND |
| + | 33.6 ± 2.8 | 2.2 ± 0.2 | 8.7 ± 0.3 | 21.9 ± 7.5 | 1.1 ± 0.6 | ||
| Acid | - | 12.3 ± 1.2 | 10.9 ± 6.7 | 2.9 ± 2.7 | 7.1 ± 1.2 | 4.6 ± 0.4 | |
| + | 17.3 ± 4.4 | 35.5 ± 20.1 | 8.2 ± 1.1 | 5.4 ± 0.9 | ND | ||
| Sludge | Neutral | - | 28.6 ± 23.6∗ | 2.1 ± 0.2 | 13.5 ± 0.9 | 31.5 ± 23.3 | 8.5 ± 2.2 |
| + | 6.3 ± 1.2 | 2.4 ± 0.1 | 17.6 ± 0.2 | 18.9 ± 2.6 | 7.1 ± 0.5 | ||
| Acid | - | 41.2 ± 1.6 | 8.3 ± 1.3 | 10.0 ± 0.2 | 19.2 ± 0.9 | 6.8 ± 0.6 | |
| + | 33.3 ± 5.6 | 4.8 ± 0.7 | 10.0 ± 1.6 | 16.3 ± 5.9 | 0.4 ± 0.3 | ||
| All | Neutral | - | 11.7 ± 1.2 | 2.4 ± 0.5 | 10.9 ± 0.3 | 21.2 ± 2.9 | 2.2 ± 0.2 |
| + | 2.2 ± 0.6 | 2.4 ± 0.4 | 19.1 ± 6.9 | 25.1 ± 4.7 | 10.5 ± 0.6 | ||
| Acid | - | 15.7 ± 2.8 | 2.6 ± 1.3 | 4.6 ± 4.6 | 9.5 ± 0.2 | 12.8 ± 1.4 | |
| + | 18.8 ± 2.5 | 3.2 ± 0.5 | 7.6 ± 3.8 | 7.6 ± 0.4 | 0.7 ± 0.4 | ||
| Compost | Neutral | - | 11.6 ± 1.6 | 3.0 ± 0.2 | 24.2 ± 2.5 | 31.4 ± 4.2 | 1.9 ± 0.3 |
| + | 9.6 ± 1.7 | 2.7 ± 0.2 | 24.5 ± 0.5 | 22.5 ± 6.1 | 1.2 ± 0.0 | ||
| W. soil | Neutral | - | 10.0 ± 1.3 | 6.0 ± 0.4 | 23.8 ± 1.3 | 52.7 ± 11.1 | 3.1 ± 0.6 |
| + | 11.0 ± 0.9 | 5.0 ± 0.8 | 17.5 ± 0.4 | 28.6 ± 7.7 | 1.5 ± 0.2 | ||
| Substrate only control | Acid | - | 8.7 ± 3.8 | ND | ND | ND | ND |
| + | 4.5 ± 4.0 | ND | ND | ND | ND | ||
In., Initial; [mM]max, fermentation product maximal concentration produced by the individual inoculum; ND, Not detected. ∗High [EtOH]max is due only to one replicate (n = 3), if n = 2, [EtOH]max = 4.40 mM ± 1.62 mM.