Figure 1
Process characteristics. a) The full-scale process samples were taken from the feeding material, the feeding and unloading ends of the drum and from the tunnel. b) Pilot scale process samples were taken from the drum feeding and the unloading end. The polygons indicate the Selleck CB-839 sites of sampling. Table 1 Sample metadata. Sample collection data and physical and chemical properties of the samples. Sample Age (d)1 Date of sampling Temperature (°C) pH Volume weight (g/l) Full-scale composting unit FS1 0 21.01.2002 0 4.8 470 FS2 1 21.01.2002 29 5.0 510 FS3 2-3 21.01.2002 29 6.9 440 FS4 7 21.01.2002 38 7.7 450 FS5 1 22.01.2002 26 5.0 440 FS7 0 04.02.2002 0 5.7 500 FS8 21 04.02.2002 68 7.9 330 FS9 1 08.02.2002 22 5.9 510 FS10 2-3 08.02.2002 35 7.8 550 FS11 12 08.02.2002 60 7.4 550 Pilot-scale composting unit PS1 4 02.08.2002 51 4.8 480 PS2 39 02.08.2002 51 8.4 270 PS3 4 06.08.2002 55 4.7 540 PS4 8 06.08.2002 55 8.5 430 PS5 selleck 6 08.08.2002 44 4.8 530
PS6 10 08.08.2002 55 8.5 410 PS7 15 09.07.2002 50 5 540 PS8 19 09.07.2002 70 7.7 410 1Time in days after loading of material into composting unit DNA extraction, PCR amplification and sequencing DNA was extracted from compost samples using Fast DNA®SPIN kit for soil according to the manufacturer’s instructions (Qbiogene Inc., Carlsbad, USA). DNA extracted from compost samples was used as a template for the PCR amplification of the 16S rRNA genes with primers pA and pH’ [23]. The 50 μl PCR reaction mixture contained 1 μM of each primer, 200 μM of each deoxynucleoside triphosphate, 0.5 mM of betaine, 2.5% of dimethyl sulfoxide, 0.2-1 μl of template DNA, 5 μl of F-516 10× DyNAzyme buffer, 1 U of DyNAzyme II DNA polymerase (Finnzymes, Espoo, Finland) and 0.05 U of Pfu DNA polymerase (Fermentas, Vilnius, Lithuania). The Pfu-polymerase was used to minimize the PCR derived errors [24]. Thermal cycling was carried out by initial denaturation at 94°C for 5 min, followed by 24 amplification cycles of denaturation at 94°C for 30 s, annealing at 55°C for 30 s, and elongation at
72°C for 1 min, with a final elongation TCL at 72°C for 10 min (Gradient Cycler PTC-225 Peltier Thermal Cycler PCR-apparatus, MJ Research, Waltham, USA). A low cycle number was used to avoid PCR artefact formation. The PCR products were purified with purification plates (Millipore, Massachusetts, USA) using water suction (Ashcroft®, Berea, USA). In order to enable efficient ligation, A-nucleotide-overhangs were inserted to the 3′ ends of the PCR products in a 50 μl reaction containing 5 μl of F-516 10× DyNAzyme buffer, 250 μM of deoxynucleoside triphosphate and 1 U of DyNAzyme II DNA polymerase (Finnzymes, Espoo, Finland) at 72°C for 1 h.