CHROMOGENIC EC O157:H7 AGAR, MODIFIED

Description

Escherichia coli O157:H7 belongs to the Enterohemorrhagic Escherichia coli (EHEC) group and it predominates as a food borne pathogen. E.coli O157: H7 was first recognized as a human pathogen in 1982 when two outbreaks of hemorrhagic colitis were associated with consumption of undercooked ground beef that has been contaminated with this organism. Chromogenic EC O157:H7 Agar is a chromogenic medium recommended for the isolation and differentiation of E.coli O157:H7 from food and environmental samples. Chromogenic EC O157:H7 Agar is based on the formulation described by Rappaport and Henigh. The medium contains sorbitol as a fermentable carbohydrate and a chromogenic mixture instead of lactose and indicator dyes respectively. The chromogenic substrate is specifically and selectively cleaved by Escherichia coli O157: H7 resulting in a dark purple to magenta coloured moiety. E.coli give bluish green coloured colonies.