# 194a: DESULFOTOMACULUM OX39 MEDIUM (XYLENE) ## Main sol. 194a 932 ml **Solution A** 1 ml **Solution B** 30 ml **Solution C** 20 ml **Solution D** 1 ml **Solution E** 10 ml **Solution F** 10 ml **Solution G** 1. Solution A is sparged with 80% N2 and 20% CO2 gas mixture to reach a pH below 6 (at least 30 min ), then distributed under the same gas atmosphere in anoxic serum vials (e.g., 50 ml medium in 100 ml serum bottles) and autoclaved. Solutions B, D and G are autoclaved separately under 100% N2 gas. Solution C is autoclaved under 80% N2 and 20% CO2 gas atmosphere. Solutions E and F are prepared under 100% N2 gas atmosphere and sterilized by filtration. Solutions B to G are added to the sterile, cooled solution A in appropriate amounts in the sequence as indicated. Final pH of the medium should be 7.2 - 7.4. 2. Note: For transfers use 5 - 10% (v/v) inoculum. Incubate tubes in a slanted position. ## Solution A 1.4 g Na2SO4 0.2 g KH2PO4 0.3 g NH4Cl 1 g NaCl 0.4 g MgCl2 x 6 H2O 0.5 g KCl 0.15 g CaCl2 x 2 H2O 1 ml **Selenite-tungstate solution** 0.5 ml Sodium resazurin (0.1% w/v) 930 ml Distilled water ## Solution B 1 ml **Trace element solution SL-10** ## Solution C 1.5 g Na2CO3 30 ml Distilled water ## Solution D 0.3 ml m-Xylene 20 ml 2,2,4,4,6,8,8-Heptamethylnonane ## Solution E 1 ml **Seven vitamins solution** ## Solution F 0.8 g FeSO4 x 7 H2O 10 ml H2SO4 (0.2 N) ## Solution G 0.4 g Na2S x 9 H2O 10 ml Distilled water ## Selenite-tungstate solution 0.5 g NaOH 3 mg Na2SeO3 x 5 H2O 4 mg Na2WO4 x 2 H2O 1000 ml Distilled water ## Trace element solution SL-10 10 ml HCl (25%) 1.5 g FeCl2 x 4 H2O 70 mg ZnCl2 100 mg MnCl2 x 4 H2O 6 mg H3BO3 190 mg CoCl2 x 6 H2O 2 mg CuCl2 x 2 H2O 24 mg NiCl2 x 6 H2O 36 mg Na2MoO4 x 2 H2O 990 ml Distilled water 1. First dissolve FeCl2 in the HCl, then dilute in water, add and dissolve the other salts. Finally make up to 1000.00 ml. ## Seven vitamins solution 100 mg Vitamin B12 80 mg p-Aminobenzoic acid 20 mg D-(+)-biotin 200 mg Nicotinic acid 100 mg Calcium pantothenate 300 mg Pyridoxine hydrochloride 200 mg Thiamine-HCl x 2 H2O 1000 ml Distilled water