Description
General description
GranuCult® GIOLITTI-CANTONI broth (Base) promotes the growth of staphylococci due to the presence of pyruvate, glycine, Tween® 80, and a high concentration of mannitol. This medium stimulates the growth of injured staphylococci and aids detection of the organism when present in small numbers only. Lithium chloride inhibits the Gram-negative contaminants, while potassium tellurite and glycine inhibit the Gram-positive contaminants. Furthermore, anaerobiosis suppresses the micrococci to a certain degree. Black coloration or black precipitate of the culture medium, due to reduction of tellurite to metallic tellurium, indicates the growth of staphylococci.
Application
GranuCult® GIOLITTI-CANTONI broth (Base) is suitable for the enumeration and detection of coagulase-positive staphylococci (Staphylococcus aureus and other species) from food and animal feeding stuff as well as from environmental samples in food production and food handling.
Analysis Note
Appearance (clearness): clear
Appearance (color): yellowish-brown
pH-value (25 °C): 6.7 - 7.1
Growth promotion test in accordance with the current version of DIN EN ISO 11133.
Mixed inoculum of S.aureus and E.coli.
Additionaly monoculture of E.coli.
Confirmation on Baird-Parker-Agar resp. Tryptic soy agar
Inoculum on reference medium (Staphylococcus aureus ATCC 25923 (WDCM 00034)): ≤ 100
Inoculum on reference medium (Staphylococcus aureus ATCC 6538 (WDCM 00032)): ≤ 100
Inoculum on reference medium (Escherichia coli ATCC 25922 (WDCM 00013)): ≥ 10000
Inoculum on reference medium (Escherichia coli ATCC 8739 (WDCM 00012)): ≥ 10000
Growth on Baird-Parker-Agar(Staphylococcus aureus ATCC 6538 (WDCM 00032)): >10 colonies
Growth on Baird-Parker-Agar(Staphylococcus aureus ATCC 25923 (WDCM 00034)): >10 colonies
Growth on Tryptic soy agar (Escherichia coli ATCC 25922 (WDCM 00013)): total inhibition
Growth on Tryptic soy agar (Escherichia coli ATCC 8739 (WDCM 00012)): total inhibition
Colonies (Staphylococcus aureus ATCC 25923 (WDCM 00034)): Black or grey colonies with clear halo
Colonies (Staphylococcus aureus ATCC 6538 (WDCM 00032)): Black or grey colonies with clear halo
Incubation
24 ± 2 hours at 37 ± 1 °C aerobic.
E.coli 48 ± 2 hours at 37 ± 1 °C aerobic.
Confirmation on Baird-Parker-Agar: 48 ± 2 hours at 37 ± 1 °C aerobic.
Confirmation on Tryptiy Soy-Agar: 24 ± 2 hours at 37 ± 1 °C aerobic.
Legal Information
GRANUCULT is a registered trademark of Merck KGaA, Darmstadt, Germany
NutriSelect is a registered trademark of Merck KGaA, Darmstadt, Germany
TWEEN is a registered trademark of Croda International PLC
Disclaimer
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.
