Lauryl Sulfate Broth with MUG is a liquid medium used for the detection of Escherichiacoli in water, food, and dairy products. Enzymatic Digest of Casein offers a source of nitrogen, vitamins, and minerals. Potassium Phosphates act as buffering agents and Lactose is a source of energy. Sodium Lauryl Sulfate suppresses the growth of organisms other than coliforms. Addition of the fluorogenic compound MUG (4-methylumbelliferyl-β-D-glucuronide) permits the rapid detection of E. coli through observation under UV light. MUG is degraded to 4-methylumbelliferone, a fluorescent end product, by the enzyme β-D-glucuronidase encoded in the genome of E. coli.