Detection of Specific Taxa Using Chromogenic and Fluorogenic Media
Enzymatic substrates are widely used in microbiology to study metabolic pathways, to monitor metabolism and to detect, enumerate and identify microorganisms. In general, fluorogenic and chromogenic enzyme substrates have proved to be a powerful tool, utilizing specific enzymatic activities of certain microorganisms. By incorporation of these substrates into primary selective media, enumeration and detection can be performed directly on the isolation plate. Methods and media based on the application of these substrates enable specific and rapid detection of a variety of microorganisms. Examples of target pathogens include Escherichia coli, Staphylococcus aureus, Listeria monocytogenes, Salmonella spp. and Vibrio spp. The inclusion of multiple chromogenic substrates into culture media facilitates the differentiation of polymicrobial cultures. This paper describes some developments in chromogenic and fluorogenic culture media in microbiological diagnostic in particular in food and water microbiology.