** ph : -

** memo : Solution A:
Na2SO4 3.00 g
KH2PO4 0.20 g
NH4Cl 0.30 g
NaCl 21.00 g
MgCl2 x 6 H2O 3.10 g
KCl 0.50 g
CaCl2 x 2 H2O 0.15 g
Selenite-tungstate solution (see medium 385) 1.00 ml
Resazurin 1.00 mg
Distilled water 870.00 ml
Solution B:
Trace element solution SL-10 (see medium 320) 1.00 ml
Solution C:
NaHCO3 5.00 g
Distilled water 100.00 ml
Solution D:
Na-L-lactate 2.50 g
Distilled water 10.00 ml
Solution E:
Vitamin solution (see medium 141) 10.00 ml
Solution F:
Na2S x 9 H2O 0.40 g
Distilled water 10.00 ml
Solution A is gassed with 80% N2 and 20% CO2 gas mixture to reach a pH below 6 (at least 30 min), then autoclaved anoxically under the same gas mixture. Solutions B, D and F are autoclaved separately under 100% N2 gas. Solution C is autoclaved under 80% N2 and 20% CO2 gas atmosphere. Solution E is prepared under N2 gas atmosphere and sterilized by filtration. Solution B to F are added to the sterile, cooled solution A in the sequence as indicated. The complete medium is distributed anoxically under 80% N2 and 20% CO2 gas atmosphere into appropriate vessels. Final pH of the medium should be 7.1 - 7.4.
Addition of 10 - 20 mg sodium dithionite per liter (e.g. from 5% (w/v) solution, freshly prepared under N2 and filter-sterilized) may stimulate growth at the beginning. For transfers use 5 - 10% inoculum.

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