ETGPA (Egg Tellurite Glycine Pyruvate Agar)

[所属分类:培养基配方] [发布时间:2020-7-9] [发布人:] [阅读次数:] [返回]

山东拓普生物工程有限公司

Shandong Tuopu Biol-Engineering Co.,Ltd

ETGPA
(Egg Tellurite Glycine Pyruvate Agar)

培养基配方
Composition per liter:
Agar......................................................................17.0g
Glycine...................................................................12.0g
Sodium pyruvate...........................................................10.0g
Pancreatic digest of casein...............................................10.0g
Beef extract..............................................................5.0g
LiCl......................................................................5.0g
Yeast extract.............................................................1.0g
Egg yolk emulsion........................................................50.0mL
K2TeO3 solution..........................................................10.0mL
pH 7.0 ± 0.2 at 25°C
Source:  This medium is available as a premixed powder from BD Di-
agnostic Systems.
Egg Yolk Emulsion:
Composition :
Chicken egg yolks.........................................................11
Whole chicken egg ........................................................1
Preparation of Egg Yolk Emulsion:  Soak egg with 1:100 dilution
of saturated mercuric chloride solution for 1 min. Crack eggs and sep-
arate yolks from whites. Mix egg yolks with 1 chicken egg.
K2TeO3 Solution:
Composition per 100.0mL:
K2TeO3 .................................................................1.0g
Preparation of K2TeO3 Solution: Add K2TeO3 to distilled/deion-
ized water and bring volume to 100.0mL. Mix thoroughly. Filter ster-
ilize.
Caution: Potassium tellurite is toxic.
Preparation of Medium: Add components to distilled/deionized
water and bring volume to 940.0mL. Mix thoroughly. Gently heat and
bring to boiling. Autoclave for 15 min at 15 psi pressure–121°C. Cool
to 45°–50°C. Add 10.0mL of sterile 1% tellurite solution and 50.0mL
of sterile egg yolk emulsion. If desired, add sulfamethazine to a final
concentration of 50.0mg/mL. Mix thoroughly but gently and pour into
sterile Petri dishes.
Use: For the selective isolation and enumeration of coagulase-positive
staphylococci from food, skin, soil, air, and other materials. For the dif-
ferentiation and identification of staphylococci on the basis of their
ability to clear egg yolk. Addition of sulfamethazine inhibits the
growth of Proteus. Gray-black colonies surrounded by a clear zone are
diagnostic for Staphylococcus aureus.