V. cholerae and Photobacterium damsela are used to perform quality control on TCBS agar. After overnight incubation, no growth is observed. What is the next course of action?
a. Reinoculate the TCBS agar, and incubate for 36 hours.
b. Check the pH to ensure that it is 8.6.
c. Reincubate the plates for another 24 hours.
d. These two organisms are poor choices for quality control on TCBS agar.
B
The pH of TCBS is 8.6, which inhibits the growth of other intestinal flora; therefore if the organ-isms do not grow on the agar, then the pH may be off, retarding the growth. V. cholerae appears yellow on TCBS, and P. damsela appears green.
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