Patent ID: 6087156
Filing Date: 2000-07-11
Classification: C12Q

Abstract:
An isolation plating medium for use in processes for the presumptive identification of Escherichia coli 0157:H7 consisting essentially of a mixture of (1) an ingredient which selectively promotes growth of Escherichia coli cells under incubation, (2) an ingredient that inhibits growth of gram positive microorganisms under incubation, (3) an ingredient that inhibits growth of Proteus sp. under incubation, (4) an ingredient that inhibits the growth of strains of Escherichia coli other than Escherichia coli 0157:H7 under incubation, (5) a plurality of carbohydrates selected from the group consisting of sorbitol, salicin, inositol, and adonitol, (6) a pH indicator dye that changes the color of the plating medium to a first color when the pH of the medium changes, (7) a chromogenic substrate that reacts to beta-galactosidase to form a precipitate of a second color which contrasts with the first color, whereby a microorganism which ferments one or more of the carbohydrates but does not produce beta-galactosidase will produce colonies in the plating medium of the first color, a microorganism which does not ferment a carbohydrate but produces beta-galactosidase will produce colonies in the plating medium of the second color, and a microorganism which ferments at least one of the carbohydrates and produces beta-galactosidase will produce colonies in the medium of a third color which is a mixture of the first and second colors, and (8) a sufficient mass of an agent to solidify the mixture.