# 1597b: NATRANAEROFABA MEDIUM ## Main sol. 1597b 500 ml **Solution A** 500 ml **Solution B** 1 ml **Solution C** 1 ml **Solution D** 5 ml **Solution E** 10 ml **Solution F** 5 ml **Solution G** 10 ml **Solution H** 10 ml **Solution I** 1. Sterilize solutions A and B in closed thick-walled screw-top bottles (e.g., SCHOTT) for 20 min at 120°C. The pH of solution A after sterilization should be 10. There is some precipitate forming that settles at the bottom after 3 - 4 days. It is best to remove precipitates by decantation before using solution A for medium preparation. 2. Combine solution A with solution B and sparge medium with 100% N2 gas for at least 30 - 45 min to make it anoxic, then dispense under same gas atmosphere into anoxic Hungate-type tubes or serum vials and autoclave. Solutions C to I are sterilized separately under 100% N2 gas. Vitamins and pyruvate should be sterilized by filtration. To complete the medium appropriate amounts of solutions C to I are added to the combined sterile solutions A and B in the sequence as indicated. Final pH of the medium should be 9.5. 3. Note: 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. ## Solution A 92.5 g Na2CO3 17.5 g NaHCO3 8 g NaCl 0.5 g K2HPO4 500 ml Distilled water ## Solution B 120 g NaCl 1.25 g K2HPO4 2.5 g KCl 500 ml Distilled water ## Solution C 1 ml **Trace elements solution (Pfennig & Lippert,1966)** ## Solution D 1 ml **Selenite-tungstate solution** ## Solution E 0.2 g NH4Cl 0.25 g MgSO4 x 7 H2O 5 ml Distilled water ## Solution F 2.2 g Na-pyruvate 10 ml Distilled water ## Solution G 0.5 g Yeast extract 5 ml Distilled water ## Solution H 10 ml **Wolin's vitamin solution** ## Solution I 0.25 g Na2S x 9 H2O 10 ml Distilled water ## Trace elements solution (Pfennig & Lippert,1966) 5 g EDTA 2.2 g FeSO4 x 7 H2O 0.1 g ZnSO4 x 7 H2O 0.03 g MnCl2 x 4 H2O 0.03 g H3BO3 0.2 g CoCl2 x 6 H2O 0.03 g CuCl2 x 2 H2O 0.03 g NiCl2 x 6 H2O 0.03 g Na2MoO4 x 2 H2O 1000 ml Distilled water 1. pH 3.0-4.0 ## Selenite-tungstate solution 0.5 g NaOH 3 mg Na2SeO3 x 5 H2O 4 mg Na2WO4 x 2 H2O 1000 ml Distilled water ## Wolin's vitamin solution 2 mg Biotin 2 mg Folic acid 10 mg Pyridoxine hydrochloride 5 mg Thiamine HCl 5 mg Riboflavin 5 mg Nicotinic acid 5 mg Calcium D-(+)-pantothenate 0.1 mg Vitamin B12 5 mg p-Aminobenzoic acid 5 mg (DL)-alpha-Lipoic acid 1000 ml Distilled water