What type of broth is used in the confirmed test of the Multiple Tube Fermentation Test?

In the confirmed test of the Multiple Tube Fermentation Test, Brilliant Green Lactose Bile Broth is used primarily due to its effectiveness in isolating and detecting coliform bacteria, particularly E. coli. This broth contains lactose, which serves as a fermentable carbohydrate, allowing for the observation of gas production as a sign of fermentation. Additionally, the presence of bile salts and brilliant green dye inhibits the growth of non-target organisms, thereby enhancing the selectivity of the test.

The significance of this broth lies in its ability to create conditions that favor the growth of coliforms while suppressing other types of bacteria that might interfere with the results. This facilitates a more accurate assessment of water quality and the presence of potentially harmful microorganisms.