Probiotic Attribute Analysis – Acid Tolerance


The organism must be preferred to the intestinal microflora balance. 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 organisms must be tolerant to a low pH 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 5 flasks each.
  2. Set pH at 2-3-4-5-6 with the pH-meter using 5M HCL.
  3. Autoclave the flasks and let the medium cool down.
  4. Inoculate the culture with a sterile inoculating loop.
  5. Incubate at shaker at 37°C 24 h.
  6. Take 100μl from each flask and put it on an autoclave petri plates, spread the culture over the plate well soothe culture is equally dispensed.
  7. Plate all the portions on different plates of MRS agar incubate at 37°C for 24 hours.
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