Harlequin™ Chromogenic Agar for Salmonella Esterase (CASE)

Product information

CASE is a selective chromogenic agar for the detection of Salmonella. It utilises a dual chromogenic system to differentiate between Salmonella and non-target organisms that grow on the agar.

The first chromogen is a target for esterase activity present in Salmonella species. Utilisation of this chromogen results in blue/green colonies. The second chromogen is a target for ß-glucosidase present in non-target organisms that are able to grow on the agar and also possess esterase activity. Utilisation of the second chromogen masks the utilisation of the first resulting in black colonies in non-Salmonella.

All other organisms are either inhibited or grow colourless on the agar. The media is able to detect non-motile Salmonella (S.Pullorum and S.Gallinarum) as well as monophasic variants (1,4,[5],12:i:-). The media is also able to detect serovars that present weak esterase activity (S.Dublin), and lactose positive strains (S.Arizonae).