This HiDip slide is recommended for detection of E.coli, coliforms & S.aureus with inactivation of disinfectants. Hicrome™ ECC Agar- The chromogenic mixture contains two chromogenic substrates. The enzyme b-D-galactosidase produced by coliforms cleaves one of the chromogen to form salmon to red coloured colonies. The enzyme b-D-glucuronidase produced by E. coli, cleaves X-glucuronide, the other chromogen. Baird Parker Agar w/Neutralizers : The medium was developed by Baird Parker for isolation and enumeration of Staphylococci. On this medium coagulase positive colonies appear white to grey black surrounded by an opaque zone due to coagulase activity within 24-48 hours incubation at 35°C. Lithium chloride and potassium tellurite inhibit most of the contaminating microflora except Staphylococcus aureus. Lecithin , sodium thiosulphate, tween 80 and histidine are the neutralizers.