Product number: HAL012

Harlequin® Cronobacter sakazakii Isolation Medium is used for the isolation of Enterobacter sakazakii from milk and milk product as recommended under ISO/TS 22964:2006(E).

Harlequin CSIM was developed to isolate and differentiate Cronobacter sakazakii (formerly Enterobacter sakazakii), a member of the Enterobacteriaceae family. C. sakazakii is differentiated when it hydrolyses the chromogenic substrate 5-bromo-4-chloro-3-indolyl-α-D-glucopyranoside present in the medium. Sodium deoxycholate and crystal violet were included in the formula to make the medium more selective.

Typical Formulation g/Liter
Pancreatic peptone of casein 7 g
Yeast extract 3 g
Sodium chloride 5 g
Sodium deoxycholate 0.6 g
5-bromo-4-chloro-3-indolyl-α-D-Glucoside 0.15 g
Crystal violet 0.002 g
Agar 14 g
Grams per liter 29.75 g

Final pH: 7.0 ± 0.2


  1. Weigh 29.75 grams of powder and disperse in 1 liter of deionized water.
  2. Allow to soak for 10 minutes, swirl to mix
  3. Autoclave for 15 minutes at 121°C.
  4. Cool to 47°C and mix well before dispensing into Petri dishes.

Order Details

Product # Product Description
HAL012A Harlequin CSIM (ISO) – 500 g

Reference Material

HAL012 - Harlequin CSIM (ISO), Product Information Sheet [English]

For additional information or questions about product SDS documents, please contact Neogen at

Please check with your local representative for availability of these products within your region.