Methane-yielding microbial communities processing lactate-rich medium to methane | ||
---|---|---|
M1A | M1B | |
The seed methanogenic inoculum | Activated sludge from a municipal waste treatment plant “Warszawa Południe” in Warsaw, Poland, sampled in the wintera | Methane-yielding sludge from the 50-L-UASB bioreactor processing acidic effluent from molasses fermentation [19] inoculated with activated sludge from a municipal waste treatment plant “Warszawa Południe” in Warsaw, Poland, sampled in the autumna |
Lactate-rich medium—modified M9 (containing MgCl2 instead of MgSO4, without glucose) | Sodium lactate 8.26 g/L, butyric acid 1.06 g/L, propionic acid 0.97 g/L, acetic acid 1.54 g/L | Sodium lactate 7 g/L, sodium butyrate 1.3 g/L, propionic acid 0.99 g/L, acetic acid 1.05 g/L, yeast extract 0.5 g/L |
Hydraulic retention time (HRT), days | 7 | 7 |
Culture history | - Incubation at room temperature (20–25 °C) for 26 days after inoculation - 27th–57th day of cultivation—neutralized medium continuously supplied to the bioreactor - Since 58th day of cultivation—non-neutralized medium supplied to the bioreactor | Incubation at room temperature (20–25 °C) for 10 days after inoculation. Since 11th day of cultivation—non-neutralized medium supplied to the bioreactor |
Sample collection for 16S rRNA profiling | 37th week of cultivation | 40th week of cultivation |
Analyses performed on the samples collected from the UASB reactors shown in Table 2 | 33rd—40th week of cultivation | 35th—40th week of cultivation |
Sample collection for isotope analyses of fermentation gas | – | 44th—50th week of cultivation |