BBL™ CHROMagar™ Listeria

Products

Chromogenic Media

Chromogenic Media

Features

BBL CHROMagar Listeria

BBL CHROMagar Listeria BBL™ CHROMagar™ Listeria

Available as prepared plated media in packs of 20.

BBL™ CHROMagar™ Listeria is a selective, differentiation medium for the isolation and confirmation of Listeria monocytogenes out of food and environmental samples. Recommended in the US FDA-CFSAN Bacteriology Analytical Manual (BAM) and AOAC-RI approved.

CHROMagar™ Listeria features:

AOAC-RI approved
Faster results!
Improved accuracy!
Cost effective! Saves materials and labor
High Sensitivity – detects low numbers of L. monocytogenes in mixed populations
High Specificity 100%
Time to results 24 to 48 hours starting at pre-enrichment
Confirmation of L.monocytogenes and L.ivanovii

Results

After proper incubation, read plates against a white background with good lighting. A blue-green colony surrounded by an opaque, white halo on BBL CHROMagar Listeria is indicative of L. monocytogenes / L. ivanovii. Other Listeria species will produce blue-green colonies without a halo. Gram-negative organisms are inhibited. Gram-positive organisms, other than Listeria species, will either be inhibited or produce white colonies.

Principles

Specially selected Difco peptones supply nutrients. The addition of selective agents inhibits the growth of gram-negative organisms, yeast and fungi. The chromogen is a chromogenic substrate that produces a blue-green colored compound when hydrolyzed by an enzyme specific to Listeria species. CHROMagar^TM Listeria contains specific chromogenic substrates that detect the phospholipase activity specific of L. monocytogenes . Studies using BBL CHROMagar Listeria for testing a variety of food and environmental samples demonstrated 99-100% sensitivity and 100% specificity with a detection level of 1-18 CFU/25 g.

Procedure

1. Enrich sample in enrichment broth i.e. buffered peptone water, half fraser broth, UVM modified enrichment broth, at 30 degrees C. for 24 hours.

2. Inoculate CHROMagar^TM Listeria plate with 0.1ml of the enrichment broth and streak for isolation. Incubate at 35 degrees C. for 24 hours.

3. Observe plates for characteristic colonial morphology and color at 24 hours. If negative for Listeria monocytogenes, re-incubate for an additional 12-24 hours and read again.

4. For additional, biochemical confirmation, select a single colony to be tested using the Microgen^TM Listeria ID strip.

AOAC is a trademark and Performance Tested Methods Program is a service mark of AOAC International. CHROMagar is a trademark of Dr. A. Rambach. BD, BD Logo and BBL are trademarks of Becton, Dickinson and Company. ©2005 BD

Literature

icon Bdcatapult Summer2005 (316.22 kB)
icon Bdcatapult Winter2005 (548.61 kB)
icon CHROMagarListeria (379.52 kB)
icon GeneralbrochureBDchromagar (701.15 kB)
icon Listeriaflowchart (29.7 kB)
icon ListeriaprocedureVerification (497.18 kB)

Specs

BBL CHROMagar Listeria
Storage:	Upon receipt store at 2-8 degrees C. out of direct light. Product is light and temperature sensitive; shielded of light, excessive heat and freezing. The expiration date applies to the product in its intact packaging when stored as directed. This product has a 90 day shelf life starting at the date of manufacture.