MUG EC Broth, Modified is recommended for the detection and enumeration of Escherichia coli in surface and waste water by miniaturized method (MPN). This medium permits rapid detection of E. coli when medium is observed under UV light for fluorescence. It also detects anaerogenic strains which may not be detected in conventional procedure. MUG is hydrolysed by an enzyme ß-glucuronidase possessed by Escherichia coli to yield a fluorescent end product 4-Methylumbelliferone.