# J1004: FRESHWATER MEDIUM FOR SOIL AOA ## Main sol. J1004 ## Basic FWM solution 1 g NaCl 0.5 g KCl 0.4 g MgCl2 x 6 H2O 0.2 g KH2PO4 0.1 g CaCl2 x 2 H2O 1000 ml Distilled water 1. Autoclave Basic FWM solution and aseptically add the following solutions (autoclaved or *filter-sterilized) in the given order: 1 ml **Modified trace element mixture** 1 ml **Vitamin solution** (*) 1 ml FeNa-EDTA (pH 7.0, *, 7.5 mM) 2 ml NaHCO3 (*, 1 M) 10 ml **HEPES solution** 1 ml NH4Cl (1 M) 1 ml Sodium pyruvate (*, 1 M) 2. Use glass or polystyrene containers for cultivation. Cultivate in the dark without shaking. ## Modified trace element mixture 12.5 ml HCl (25%) 30 mg H3BO3 100 mg MnCl2 x 4 H2O 190 mg CoCl2 x 6 H2O 24 mg NiCl2 x 6 H2O 2 mg CuCl2 x 2 H2O 144 mg ZnSO4 x 7 H2O 36 mg Na2MoO4 x 2 H2O 987 ml Distilled water ## Vitamin solution 20 mg Biotin 20 mg Folic acid 100 mg Pyridoxine hydrochloride 50 mg Thiamine HCl 50 mg Riboflavin 50 mg Nicotinic acid 50 mg DL-Calcium pantothenate 1 mg Vitamin B12 50 mg p-Aminobenzoic acid 2 g Choline chloride 1000 ml Distilled water 1. Adjust pH to 7.0 with KOH. ## HEPES solution 12 g NaOH 119.2 g HEPES (free acid) 1. Dissolve NaOH in 300 ml distilled water. While stirring vigorously, slowly add HEPES until completely dissolved. Fill up to 450 ml with distilled water. If 1 ml of this solution is added to 100ml of the medium (containing all additive but HEPES), pH should be around 7.6 at 30C. Otherwise, adjust pH of the HEPES solution with 10 N NaOH or conc. HCl. Finally fill up to 500 ml with distilled water.