** ph : 7.1--7.4

** memo : Solution A is boiled for a few minutes, cooled to room temperature, gassed with 80% N_2_+ 20% CO_2_ gas mixture to reach a pH below 6, then autoclaved anaerobically under the same gas mixture. Solutions B, D, E and F are autoclaved separately under nitrogen. Solution C is filter-sterilized and flushed with 80% N_2_ + 20% CO_2_ to remove dissolved oxygen. Solution B to F are added to the sterile, cooled solution A in the sequence as indicated. The complete medium is distributed anaerobically under 80% N_2_ + 20% CO_2_ into appropriate vessels. Final pH of the medium is 7.1 - 7.4.
Addition of 10 - 20 mg sodium dithionite per liter (e.g. from 5% (w/v) solution, freshly prepared under N_2_ and filter-sterilized) may stimulate growth at the beginning. For transfers use 5 - 10% inoculum.

** additional actions :