How could you determine whether a bacterium fermentd the following carbohydrates: <span title="mannitol,sorbitol,adonitol,">mannitol,sorbitol,adonito...</span>

Question

How could you determine whether a bacterium fermentd the following carbohydrates: mannitol,sorbitol,adonito...

Answer 1

Broth solutions of each of these carbohydrates would be prepared in individual solutions with a pH indicator dye added (usually a 1% solution) with some additional ingredients needed for good bacterial growth.  Before sterilization a small shell vial is inserted upside down in the tube to catch any gases released during fermentation (if it occurs).  The media are sterilized and then inoculated with the bacterium of interest.  After incubation of 18 to 24 hours, the pH indicator will change color if acid is produced and gas will be trapped in the shell vial if gas is released as well.