Buffered Listeria Enrichment Broth (base)

GranuCult^® Buffered Listeria Enrichment Broth (base) is a modification of the formulation of Tryptic Soy Broth (CASO) with the addition of 6 g/L yeast extract and by increasing its buffering strength. Dextrose is the carbohydrate source. Sodium chloride maintains the osmotic balance of the medium. Phosphate acts as a buffer. Sodium pyruvate mediates the recovery of sub-lethally damaged Listeria spp. The addition of acriflavine, cycloheximide, and nalidixic acid inhibits the growth of the accompanying flora.


Listeria selective enrichment supplement (1.11781) is available to enhance selectivity and growth conditions.

GranuCult^® Buffered Listeria Enrichment Broth (base) is suitable for the selective enrichment of Listeria spp.

Appearance (clearness): clear
Appearance (colour): yellowish-brown
pH-value (25 °C): 7.1 - 7.5
Inoculum on reference medium (Listeria monocytogenes ATCC 19114 (WDCM 00110)):
Inoculum on reference medium (Listeria monocytogenes ATCC 19111 (WDCM 00020)):
Inoculum on reference medium (Listeria innocua ATCC 33090 (WDCM 00017)):
Inoculum on reference medium (Escherichia coli ATCC 25922 (WDCM 00013)):
Inoculum on reference medium (Enterococcus faecalis ATCC 19433 (WDCM 00009)):
Colony count (Listeria monocytogenes ATCC 19114 (WDCM 00110)): ≥ 1E+08 CFU/ml
Colony count (Listeria monocytogenes ATCC 19111 (WDCM 00020)): ≥ 1E+08 CFU/ml
Colony count (Listeria innocua ATCC 33090 (WDCM 00017)): ≥ 1E+08 CFU/ml
Growth (Escherichia coli ATCC 25922 (WDCM 00013)): no growth
Growth (Enterococcus faecalis ATCC 19433 (WDCM 00009)): passes test
Incubation 48 h at 30 °C

Replaces: 1.09628.5007

GRANUCULT is a registered trademark of Merck KGaA, Darmstadt, Germany

NutriSelect is a registered trademark of Merck KGaA, Darmstadt, Germany

We offer two media types: the superior granulated GranuCult^® and the cost-efficient powdered NutriSelect^® culture media, depending on your needs. The designations basic, plus, or prime are added to indicate the quality control level, from basic quality control to standard QC plus to prime for full regulatory compliance.