In Brilliant Green Agar, what does the inhibitor target?

In Brilliant Green Agar, the medium is specifically designed to inhibit the growth of certain types of bacteria. The inhibitor in Brilliant Green Agar primarily targets gram-positive organisms, which means that the presence of this agent allows for the selective cultivation of gram-negative bacteria, particularly enteric pathogens.

Brilliant Green Agar works by using a dye that notably suppresses the gram-positive flora, thereby allowing only gram-negative organisms, including coliforms and other enteric pathogens, to grow. This selective inhibition makes it easier to isolate and identify gram-negative bacteria and distinguish them from those that might interfere with the analysis.

Because it inhibits gram-positive organisms, the medium is highly effective for isolating coliforms from fecal samples and determining the presence of enteropathogenic gram-negative bacteria. Thus, the correct conclusion is that the inhibitor targets both coliforms and gram-positive organisms, enabling a focus on the gram-negative species of interest. The mechanism of action underlines the importance of selective media in microbiological diagnostics and research.