Used in microbiology for the detection and enumeration of coliforms and Escherichia coli in water, food, and environmental samples. The medium supports the growth of target organisms while inhibiting non-coliform bacteria. When E. coli is present, it produces β-glucuronidase, which cleaves the MUG substrate to release a fluorescent compound under UV light, allowing for quick and specific identification. This makes EC-MUG ideal for confirming fecal contamination in water testing and ensuring compliance with public health standards.