Probiotic Attribute Analysis – Bile tolerance


The survivability and colonization in the digestive tract are considered critical to ensure optimal functionality and expression of health promoting physiological functions by probiotics. To survive in the gut, the organism must be tolerant to the bile toxicity prevalent in the upper digestive tract. For colonization, they should exhibit good surface.


  1. Bacterial culture
  2. Eppendorf tubes


  1. Make 50 ml MRS broth in 2 flasks each.
  2. Add 1.5% and 2% bile salt to the MRS broth.
  3. Autoclave the flask and let the medium cool down.
  4. Inoculate the microbial culture with a sterile inoculating loop in MRS broth supplemented with 1.5% and 2.0% bile salts.
  5. Divide the portions MRS broth with microbial culture over a time interval of 0, 1 and 2 hours.
  6. Plate all the portions on different plates of MRS agar and incubate at 37°C for 24 hours.
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