Enterococci Broth, Chromocult (Chromocult Enterococci Broth)

[所属分类:培养基配方] [发布时间:2020-7-7] [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

Enterococci Broth, Chromocult
(Chromocult Enterococci Broth)

培养基配方
Composition per liter:
Peptone .....................................................................8.6g
NaCl.........................................................................6.4g
Tween 80.....................................................................2.2g
NaN3 ........................................................................0.6g
5-Bromo-4-chloro-3-indolyl-β- D -glucopyranoside (X-GLU) .....0.04
pH 7.5 ± 0.2 at 25°C
Source: This medium is available from Merck.
Preparation of Medium: Add components to distilled/deionized
water and bring volume to 1.0L. Mix well. Distribute into tubes. Auto-
clave for 15 min at 15 psi pressure–121°C. The prepared broth is clear
and yellowish.
Use: For the detection of enterococci in food and water. The sodium
azide present in this medium largely inhibits the growth of the accom-
panying, and especially the Gram-negative microbial flora while spar-
ing the enterococci. The substrate X-GLU (5-bromo-4-chloro-3-indo-
lyl-β- D -glucopyranoside) is cleaved, stimulated by selected peptones,
by the enzyme β- D -glucosidase which is characteristic for enterococci.
This results in an intensive blue-green color of the broth. Azide, at the
same time, prevents a false positive result by most other β- D -glucosi-
dase positive bacteria. Therefore, the color change of the broth largely
confirms the presence of enterococci and group D streptococci.