XLT4 AGAR (BASE) (C15-1297-019)

General description

GranuCult^® XLT4 agar (Base) contains a selection of suitable nutrients and vitamins (peptones, yeast extract) that allow optimal growth of salmonellae. The surfactant NIAPROOF-4 (formerly Tergitol-4/Sodiumtetradecylsulfate) inhibits the accompanying flora. Salmonellae, due to H₂S-formation (thiosulfate and iron (III)-ions), can be easily detected as black colonies on a red-violet background and differentiated from the residual accompanying flora. E. coli shows yellow colonies on a yellow background due to acidification of the medium (pH-indicator: phenol-red). Other accompanying organisms, like Shigella, will grow colorless on a red background due to a missing H₂S-formation and acidification.

Application

GranuCult^® XLT4 agar (Base) is suitable for the isolation and identification of pathogenic Enterobacteriaceae, especially Salmonella spp.

Analysis Note

Appearance (clearness): clear
Appearance (colour): red
pH-value (25 °C): 7.2 - 7.6
Growth (Salmonella enteritidis ATCC 13076 (WDCM 00030)): good to very good
Growth (Salmonella typhimurium ATCC 14028 (WDCM 00031)): good to very good
Growth (Salmonella anatum ATCC 9270): fair to very good
Growth (Shigella sonnei ATCC 11060): fair to very good
Growth (Shigella flexneri ATCC 12022 (WDCM 00126)): good to very good
Growth (Enterobacter aerogenes ATCC 13048): fair to good
Growth (Citrobacter freundii ATCC 8090): fair to good
Growth (Escherichia coli ATCC 25922 (WDCM 00013)): none to fair
Growth (Proteus mirabilis ATCC 14273): none to poor
Black centre (Salmonella enteritidis ATCC 13076 (WDCM 00030)): +
Black centre (Salmonella typhimurium ATCC 14028 (WDCM 00031)): +
Black centre (Salmonella anatum ATCC 9270): +
Colony colour (Shigella sonnei ATCC 11060): colourless
Colony colour (Shigella flexneri ATCC 12022 (WDCM 00126)): colourless
Colony colour (Enterobacter aerogenes ATCC 13048): yellow
Colony colour (Citrobacter freundii ATCC 8090): yellow
Colony colour (Escherichia coli ATCC 25922 (WDCM 00013)): colourless to yellow
Incubation: 24 - 48 hrs. at 35 °C.
Base tested withXLT4 agar supplement Art. 1.08981.

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.

Legal Information

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

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