In the MPN procedure, what is the media used to confirm the presence of total coliform?

The media used in the Most Probable Number (MPN) procedure to confirm the presence of total coliform is Brilliant Green Lactose Bile Broth. This selective broth medium is specifically designed to support the growth of coliform bacteria while inhibiting the growth of non-coliforms, making it effective for detecting and enumerating coliforms in water samples.

Brilliant Green Lactose Bile Broth contains lactose and provides a fermentable carbohydrate source, which is essential for coliforms that ferment lactose to produce gas. The production of gas in the broth is one of the key indicators used to confirm the presence of coliform bacteria in the sample. The presence of gas is monitored in the Durham tube, which is a small inverted tube within the broth that captures any gas produced during fermentation.

In contrast, other media options, while useful for different purposes or specific microorganisms, do not serve the same primary function for coliform detection in the context of the MPN procedure. MacConkey Agar is primarily used for maintaining and isolating coliforms and differentiating lactose fermenters from non-fermenters on solid media. Petri dishes serve as a general container for growth but do not have specific properties for detecting coliforms. Luria