BacterChrom™ Identification Listeria Plates

Ready-to-use chromogenic medium on 90mm plates for the confirmation of L. monocytogenes species from suspect colonies
Code: 01030
Packaging: 10 plates/box or as per customer requirements.
Storage Conditions: 2–8°C.
Transportation: Ambient temperature.
Shelf Life: 03 months from the date of manufacture.

INTENDED USE

BacterChrom™ Identification Listeria is a selective chromogenic medium designed for the confirmation and differentiation of Listeria monocytogenes species from colonies isolated on BacterChrom™ Listeria. This medium supports microbiological testing in food safety and environmental monitoring by distinguishing pathogenic L. monocytogenes from other Listeria species, such as L. ivanovii and L. innocua.
This medium is intended for use in food processing facilities, helping to prevent contamination across various stages of the production chain.
The packaging with semi-permeable Cellophane film helps balance the humidity of the environment during storage.

PRINCIPLES

BacterChrom™ Identification Listeria incorporates chromogenic substrates that react with specific enzymatic activities of Listeria monocytogenes, producing distinct colony appearances. The selective agents inhibit the growth of non-target organisms, ensuring specificity. This allows for a rapid presumptive identification process, simplifying laboratory workflows and supporting food safety protocols.

Allow to warm to room temperature before inoculation, dry the plates in an incubator with the covers partially removed.
Select typical isolated colonies from BacterChrom™ Listeria, characterized by blue colonies with a white halo after 24 ± 2 hours of incubation at 37 °C ± 1 °C.
Do a zigzag streak on the surface of the medium.
Incubate 18h to 24 h at 37 °C +/- 1 °C.

RESULTS

Microorganism	Typical colony apprearance
L. monocytogenes	pink surrounded by a white halo
L. ivanovii	colourless surrounded by a white halo
L. innocua	pink without halo
L. seeligeri	colorless without halo
B. cereus	colorless with irregular edge (intense halo)

BacterLab ensures the quality of each product batch by testing with ATCC reference strains.

Reference strains	Incubation conditions	Expected results
L. monocytogenes ATCC 13932	Incubate for 18 – 24 hours at 35 – 37 °C	pink with halo colonies
L. innocua ATCC 33091		pink without halo colonies
L. ivanovii ATCC 19119		colorless with halo colonies
B. cereus ATCC 10876		colorless with big halo colonies

For 1 liter of medium

Peptone and yeast extract	23,0 g
Chromogenic mix	8,8 g
Sodium chloride	5,5 g
Agar	15,0 g
Selective and enrichment mix	6,5 g

pH of the ready-to-use medium at 25°C: 6,6 ± 0,2

*Note: This ingredient is for reference only our company will formulate the ingredient according to requests or tender specifications.

Product Name	Code	Packaging
BacterChrom™ Identification Listeria	01030	10 plates/box or as per customer request.