Analysis Note
Appearance (clearness): clear to almost clearAppearance (color): yellowish-brownpH-value (25 °C): 7.0 - 7.4Growth promotion test in accordance with the current version of DIN EN ISO 11133.Mixed inoculum of Listeria, E.coli and E.faecalisAdditionaly monoculture of E.coli and E.faecalisConfirmation on ALOA®-Medium resp. Tryptic soy agarInoculum on reference medium (Listeria monocytogenes ATCC 13932 (WDCM 00021)): ≤ 100Inoculum on reference medium (Listeria monocytogenes ATCC 35152 (WDCM 00109)): ≤ 100Inoculum on reference medium (Escherichia coli ATCC 25922 (WDCM 00013)): ≥ 1000Inoculum on reference medium (Escherichia coli ATCC 8739 (WDCM 00012)): ≥ 1000Inoculum on reference medium (Enterococcus faecalis ATCC 19433 (WDCM 00009)): ≥ 1000Inoculum on reference medium (Enterococcus faecalis ATCC 29212 (WDCM 00087)): ≥ 1000Blacking (Listeria monocytogenes ATCC 13932 (WDCM 00021)): +Blacking (Listeria monocytogenes ATCC 35152 (WDCM 00109)): +Blacking (Escherichia coli ATCC 25922 (WDCM 00013)): -Blacking (Escherichia coli ATCC 8739 (WDCM 00012)): -Blacking (Enterococcus faecalis ATCC 19433 (WDCM 00009)): -Blacking (Enterococcus faecalis ATCC 29212 (WDCM 00087)): -Growth on ALOA™ medium (Listeria monocytogenes ATCC 13932 (WDCM 00021)): >10 coloniesGrowth on ALOA™ medium(Listeria monocytogenes ATCC 35152 (WDCM 00109)): >10 coloniesColonies (Listeria monocytogenes ATCC 13932 (WDCM 00021)): blue green colonies with opaque haloColonies(Listeria monocytogenes ATCC 35152 (WDCM 00109)): blue green colonies with opaque haloGrowth on Tryptic soy agar (Escherichia coli ATCC 25922 (WDCM 00013)): total inhibitionGrowth on Tryptic soy agar (Escherichia coli ATCC 8739 (WDCM 00012)): total inhibitionGrowth on Tryptic soy agar (Enterococcus faecalis ATCC 29212 (WDCM 00087)): ﹤100 colonienGrowth on Tryptic soy agar (Enterococcus faecalis ATCC 19433 (WDCM 00009)): ﹤100 coloniesIncubation:Half-Fraser Broth: 24 ± 2 hours at 30 ± 1°CFraser Broth: 48 ± 2 hours at 37 ± 1°CConfirmation on ALOA™ medium: 44 ± 4 hours at 37 ±1°CConfirmation on Tryptic soy agar: 24 ± 3 hours at 37 ± 1°C
Application
GranuCult® FRASER broth (base) is suitable for the primary and secondary selective enrichment of Listeria spp. from food and animal feed as well as from environmental samples and other materials.
Footnote
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.
General description
GranuCult® FRASER broth (base) has high nutrient content and a large buffering capacity that creates optimum growth conditions for Listeria spp. Lithium chloride, nalidixic acid, and acriflavine hydrochloride inhibit the growth of accompanying bacteria. The addition of aesculin and ammonium iron (III) citrate facilitates the detection of the β-D-glucosidase activity by forming a black complex of aesculin with iron (III) ions. A black coloration can develop during incubation, but this reaction is not exclusive to Listeria spp. and cultures that show no blackening cannot be assumed to be free of Listeria spp. Hence, every primary and secondary enrichment in Fraser broth must be sub-cultured on selective plating media. From GranuCult® FRASER Broth (Base), the primary selective enrichment Half Fraser broth, as well as the secondary enrichment Fraser broth can be prepared by addition of Ammonium iron (III) citrate supplement (1.00092) and Selective Supplement (1.00093).
Legal Information
NutriSelect is a registered trademark of Merck KGaA, Darmstadt, Germany
GRANUCULT is a registered trademark of Merck KGaA, Darmstadt, Germany
ALOA is a registered trademark of Biolife Italiana S.r.l.
Linkage
Replaces: 1.10398
Packaging
500 g in Plastic bottle
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