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  5. BAM Media M145: Tetrathionate (TT) Broth
  1. Laboratory Methods (Food)

BAM Media M145: Tetrathionate (TT) Broth

Media Index for BAM

January 2001

Tetrathionate broth base

Polypeptone 5 g
Bile salts 1 g
Calcium carbonate 10 g
Sodium thiosulfate·5H2O 30 g
Distilled water 1 liter

Suspend ingredients in 1 liter distilled water, mix, and heat to boiling. DO NOT AUTOCLAVE. (Precipitate will not dissolve completely.) Cool to less than 45°C. Store at 5-8°C. Final pH, 8.4 ± 0.2.

Iodine-Potassium Iodide (I2-KI) solution

Potassium iodide 5 g
Iodine, resublimed 6 g
Distilled water, sterile 20 mL

Dissolve potassium iodide in 5 ml sterile distilled water. Add iodine and stir to dissolve. Dilute to 20 ml.

Brilliant Green Solution (0.1%)

Brilliant green dye, sterile 0.1 g
Distilled water, sterile 100 mL

Dissolve 0.1 g brilliant green dye in 10 mL sterile distilled water. Dilute to 100 mL in sterile distilled water. On day of use, add 20 ml of I2-KI solution and 10 ml of brilliant green solution (0.1%) to 1 liter base. Resuspend precipitate by gentle agitation and aseptically dispense 10 ml portions into 20 × 150 or 16 × 150 mm sterile test tubes. Do not heat medium after addition of I2-KI and dye solutions.  

Original Source: Bacteriological Analytical Manual, 8th Edition, Revision A, 1998.

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