Cysteine Lactose Electrolyte Deficient (RDM-CLED-01) recommended for selective isolation and differentiation of Lactose fermenting and Lactose non-fermenting enteric bacteria from water, sewage, foods, dairy products etc. Specifically the coliforms; E coli. The modification CLED took place by removing mannitol by L-Cystine. Peptone, serve as the source of all essential nutrients such as amino acids, vitamins, other trace factors which are essential for the growth of microbes and lactose in it plays a crucial role for selection of lactose fermenting microbes. Moreover the combination of crystal violet and the bile salts inhibits the Gram-positive bacteria. It is a selective medium for growth of Gram Negative bacteria because of their ability to carry out lactose fermentation.