EGG YOLK TELLURITE EMULSION STERILE; 20%; FOR MICROBIOLOGY

Analysis Note

Appearance: pale yellow emulsionSterility test: sterileTypical composition: Sterile egg-yolk 200 ml; NaCl 4.25 g; potassium tellurite 2.1 g; distilled water to give a final volume of 1000 ml. Egg-yolk Tellurite Emulsion tested in BAIRD-PARKER-Agar Art. 1.05406.Inoculum on reference medium - Staphylococcus aureus ATCC 25923 (WDCM 00034): 10 - 100 - Staphylococcus aureus ATCC 6538 (WDCM 00032): 10 - 100Inoculum - Escherichia coli ATCC 25922 (WDCM 00013): >10⁴ - Escherichia coli ATCC 8739 (WDCM 00012): >10⁴ - Staphylococcus saprophyticus ATCC 15305 (WDCM 00159): >10⁴ - Staphylococcus epidermidis ATCC 12228 (WDCM 00036): >10⁴Recovery on test medium - Staphylococcus aureus ATCC 25923 (WDCM 00034): ≥ 70% - Staphylococcus aureus ATCC 6538 (WDCM 00032): ≥ 70%Growth - Escherichia coli ATCC 25922 (WDCM 00013): no growth - Escherichia coli ATCC 8739 (WDCM 00012): no growth - Staphylococcus saprophyticus ATCC 15305 (WDCM 00159): poor to fair - Staphylococcus epidermidis ATCC 12228 (WDCM 00036): poor to fairColony colour - Staphylococcus aureus ATCC 25923 (WDCM 00034): black - Staphylococcus aureus ATCC 6538 (WDCM 00032): black - Staphylococcus saprophyticus ATCC 15305 (WDCM 00159): black-grey - Staphylococcus epidermidis ATCC 12228 (WDCM 00036): black-greyClear zones - Staphylococcus aureus ATCC 25923 (WDCM 00034): + - Staphylococcus aureus ATCC 6538 (WDCM 00032): + - Staphylococcus saprophyticus ATCC 15305 (WDCM 00159): - - Staphylococcus epidermidis ATCC 12228 (WDCM 00036): -Incubation: 24 - 48 hrs. at 37°C, E.coli: 48 hrs. Reference: Tryptic soy agar.

Application

Egg-yolk tellurite emulsion is an additive consisting of an emulsion of egg-yolk used as a supplement to prepare Baird Parker agar base medium for the detection of Staphylococcus.

General description

Egg-yolk tellurite emulsion is a stabilized emulsion of egg yolk for microbiological use, which is added directly to nutrient media for the identification of strains of coagulase-positive Staphylococci by their lecithinase activity. Potassium tellurite has a selective activity and allows the growth of Staphylococcus as black colonies. Egg-yolk permits the detection of microbial lecithinase activity and tellurite reduction.

Linkage

Replaces: 1.03785.0007