U.S. flag An official website of the United States government

On Oct. 1, 2024, the FDA began implementing a reorganization impacting many parts of the agency. We are in the process of updating FDA.gov content to reflect these changes.

U.S. Food and Drug Administration
  1. Home
  2. Food
  3. Science & Research (Food)
  4. Laboratory Methods (Food)
  5. BAM Media M149: Triple Sugar Iron Agar (TSI)
  1. Laboratory Methods (Food)

BAM Media M149: Triple Sugar Iron Agar (TSI)

Media Index for BAM

January 2001

Medium 1

Medium 2
Polypeptone 20 g Beef extract 3 g
NaCl 5 g Yeast extract 3 g
Lactose 10 g Peptone 15 g
Sucrose 10 g Proteose peptone 5 g
Glucose 1 g Glucose 1 g
Fe(NH4)2(SO4)2•6H2O 0.2 g Lactose 10 g
Na2S2O3 0.2 g Sucrose 10 g
Phenol red 0.025 g FeSO4 0.2 g
Agar 13 g NaCl 5 g
Distilled water 1 liter Na2S2O3 0.3 g
  Phenol red 0.024 g
Agar 12 g
Distilled water 1 liter

These two media are interchangeable for general use.

Suspend ingredients of Medium 1 in distilled water, mix thoroughly, and heat with occasional agitation. Boil about 1 min to dissolve ingredients. Fill 16 × 150 mm tubes 1/3 full and cap or plug to maintain aerobic conditions. Autoclave Medium 1 for 15 min at 118°C.

Prepare Medium 2 in the same manner as Medium 1, except autoclave 15 min at 121°C. Before the media solidify, incline tubes to obtain 4-5 cm slant and 2-3 cm butt. Final pH, 7.3 ± 0.2 for Medium 1 and 7.4 ± 0.2 for Medium 2.

For use with halophilic Vibrio spp., add NaCl to a final concentration of 2-3%.

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

Back to Top