Explain the Completed Test - Most Probable Number Test?

Coliform colonies on EMB or Endo agar are further examined by completed test by inoculating lactose broth and nutrient agar slants from isolated colonies in confirmed test. Production of acid and gas in lactose broth and presence of gram negative rods in nutrient agar slants finally confirms the presence of E.coli in water sample and is considered to be a positive completed test.

Having gone through the discussion above, the 3 basic tests involved in detecting coliform in a water sample must be clearly understood by you. Make sure the procedure involved is clear, because we will try out these tests in the laboratory. Also a knowledge about the differential media, which are required for these tests is essential. So let us get to learn how to make these media.