416. MEDIUM FOR HELIOBACTERIUM (MHB)

KH₂PO₄ 0.5 g

NH₄Cl 0.5 g

NaCl 0.5 g

MgCl₂ × 6 H₂O 0.8 g

CaCl₂ 0.1 g

NaHCO₃ 1.5 g

Sodium acetate 1 g

Yeast extract 0.1 g

Na₂S × 9 H₂O 0.3 g

Vitamin B₁₂ 20 μg

Biotin 20 μg

Trace element solution SL-6 (see below) 1 ml

Distilled water 998.0 ml.

Trace element solution SL-6:

ZnSO₄ × 7 H₂O 0.1 g

MnCl₂ × 4 H₂O 0.03 g

H₃BO₃ 0.3 g

CoCl₂ × 6 H₂O 0.2 g

CuCl₂ × 2 H₂O 0.01 g

NiCl₂ × 6 H₂O 0.02 g

Na₂MoO₄ 0.03 g

Autoclave at 121 C° for 15 min. Adjust pH to 7.6. Boil the medium for few minutes under nitrogen gas. Add resazurin to a final concentration of 0.002% (2% solution, 1 ml per 1 L). Fill immediately into 50 ml screw-capped bottles with rubber septum and screw tighten or into Hungate tubes. Incubate in low light under anaerobic conditions.