Oxoid CM1007T 沙门氏菌显色琼脂基础 OXOID SALMONELLA CHROMOGENIC AGAR(OSCA)

Oxoid CM1007T 沙门氏菌显色琼脂基础 OXOID SALMONELLA CHROMOGENIC AGAR(OSCA)

SALMONELLA CHROMOGENIC AGAR BASE

CODE: CM1007

Salmonella Chromogenic Medium is a selective and differential agar base the identification of Salmonella species from other organisms in the family Enterobacteriaceae.

沙门氏菌显色培养基是一种选择性和差异化的琼脂培养基,用于从肠杆菌科的其他生物中鉴定沙门氏菌物种。

Typical Formula*

gm/litre

Special Peptone

10.0

Chromogenic mix

28.0

Agar

12.0

pH 7.2 ± 0.2 @ 25°C
* Adjusted as required to meet performance standards

SALMONELLA SELECTIVE SUPPLEMENT

Code: SR0194

Vial contents (each vial is sufficient for 500ml of medium)
per vial
per litre
Cefsulodin

6.0mg

12.0mg

Novobiocin

2.5mg

5.0mg

Directions
Suspend 25g in 500ml of distilled water and add the contents of one vial of Salmonella Selective Supplement (SR0194) reconstituted as directed. Mix well and bring to the boil with frequent agitation. DO NOT AUTOCLAVE. DO NOT HOLD AT BOILING TEMPERATURE. Cool to 50°C, mix well and pour into sterile Petri dishes.

方向
将 25g 悬浮在 500ml 蒸馏水中,然后加入一瓶按照指示重新配制的沙门氏菌选择性补充剂 (SR0194)。 充分混合并经常搅拌煮沸。 不要高压灭菌。 不要保持在沸腾温度。 冷却至 50°C,充分混合并倒入无菌培养皿中。

Description
Salmonella Chromogenic Medium is designed to identify Salmonella species based on their utilisation of one chromogenic substrate. Their inability to utilise another chromogenic substrate, that most other members of the family Enterobacteriaceae can utilise, enables rapid and reliable identification of Salmonella species.

There are in excess of 2000 known species of Salmonella, some of which differ from the typical rod-shaped, Gram-negative motile bacterium. In the U.S. alone there are between 800,000 and 4 million reported cases of salmonellosis per year resulting in 500 deaths. Infections due to Salmonella are of particular concern in the very young, the elderly and in the severely immunosuppressed where salmonellosis is recognised as an AIDS defining condition. Incidence continues to rise and infections due to Salmonella remain a principal health issue1. The widespread occurrence means there is a need for the rapid detection and identification of Salmonella in food and water to aid in the prevention and control of outbreaks2.

Traditionally, media used to differentiate Salmonella species from other members of the family Enterobacteriaceae depend upon the ability of Salmonella species to produce hydrogen sulphide coupled with their inability to ferment lactose2,3. These are, however, essentially inadequate methods, with a significant number of the 2000 plus species not exhibiting these characteristics. In recent times chromogenic media have been developed for the rapid and more reliable identification of Salmonella.

Salmonella Chromogenic Agar Base combines two chromogens for the detection of Salmonella sp., 5-Bromo-6-Chloro-3-Indolyl caprylate (Magenta-caprylate) and 5-Bromo-4-Chloro-3-Indolyl b-D galactopyranoside (X-gal). X-gal is a substrate for the enzyme b-D-galactosidase. Hydrolysis of the chromogen, Mag-caprylate, by lactose negative Salmonella species results in magenta colonies.

The medium contains bile salts to inhibit the growth of Gram-positive organisms and the addition of the Salmonella Selective Supplement SR0194 is recommended to increase the selectivity of the medium. This uses novobiocin to inhibit Proteus growth and cefsulodin to inhibit growth of Pseudomonads.

描述
沙门氏菌显色培养基旨在根据沙门氏菌对一种显色底物的利用来鉴定沙门氏菌。它们无法利用肠杆菌科的大多数其他成员可以利用的另一种显色底物,从而能够快速可靠地鉴定沙门氏菌。

已知的沙门氏菌种类超过 2000 种,其中一些与典型的杆状革兰氏阴性运动细菌不同。仅在美国,每年就有 800,000 至 400 万例沙门氏菌病报告,导致 500 人死亡。沙门氏菌引起的感染在非常年轻、老年人和严重免疫抑制的人群中尤其受到关注,沙门氏菌病被认为是艾滋病的定义疾病。沙门氏菌的发病率继续上升,沙门氏菌感染仍然是主要的健康问题1。沙门氏菌的广泛发生意味着需要快速检测和鉴定食物和水中的沙门氏菌,以帮助预防和控制暴发2。

传统上,用于区分沙门氏菌与肠杆菌科其他成员的培养基取决于沙门氏菌产生硫化氢的能力以及它们无法发酵乳糖2,3。然而,这些方法基本上是不充分的,2000 多个物种中有相当一部分没有表现出这些特征。近年来,显色培养基已被开发用于快速、更可靠地鉴定沙门氏菌。

沙门氏菌显色琼脂培养基结合了两种用于检测沙门氏菌的色原,即 5-Bromo-6-Chloro-3-Indolyl caprylate (Magenta-caprylate) 和 5-Bromo-4-Chloro-3-Indolyl bD 吡喃半乳糖苷 (X-gal )。 X-gal 是酶 b-D-半乳糖苷酶的底物。乳糖阴性沙门氏菌对色原 Mag-caprylate 的水解会产生洋红色菌落。

该培养基含有胆汁盐以抑制革兰氏阳性菌的生长,建议添加沙门氏菌选择性补充剂 SR0194 以提高培养基的选择性。这使用新生霉素来抑制变形杆菌的生长,使用头孢磺啶来抑制假单胞菌的生长。

Technique
Inoculate the plates with a food or clinical sample to produce single colonies. A Salmonella enrichment broth may be used prior to streaking out, e.g. Rappaport-Vassiliadis Enrichment Broth CM0669, Selenite Broth CM0395 & LP0121 or Tetrathionate Broth Base CM0029. Incubate for 18-24 hours at 37°C. Examine the plates for coloured colonies.

On Salmonella Chromogenic Medium CM1007 & SR0194, typical colonies will be coloured as follows:

Species

Colony Colour

Colony Diameter

Colony Morphology

Salmonella spp.

Magenta

1.0mm

Raised, smooth

Salmonella typhi

Magenta

1.0mm

Raised, smooth

Salmonella paratyphi

Magenta

1.0mm

Raised, smooth

Salmonella arizonae

Magenta / blue †

1.5mm

Raised, smooth

Salmonella gallinarum

Magenta

0.75mm

Raised, smooth

Salmonella indiana

Blue †

1.0mm

Raised, smooth

Escherichia coli

Blue

1.0mm

Raised, smooth

Enterobacter spp.

Blue

1.5mm

Raised, smooth

Klebsiella spp.

Blue

3.0mm

Raised, mucoid

Citrobacter spp.

Blue

1.5mm

Raised, mucoid

Proteus spp.

No growth / straw

0.25mm

Pseudomonas spp.

No growth

Shigella sonnei

Blue

4.0mm

Undulate

Shigella dysenteriae

Magenta

1.0mm

Raised

† Colour of colonies is a presumptive identification as it is dependent on enzyme activity. Some strains of Salmonella arizonae and Salmonella indiana can appear as blue colonies. In addition, some Shigella spp. can appear as magenta colonies. Further confirmatory tests are required.

Storage conditions and Shelf Life
Store the dehydrated medium at 10-30°C and use before the expiry date on the label.
Salmonella Selective Supplement should be stored at 2-8°C.
Store the prepared medium for up to 6 weeks at 2-8°C.

Appearance
Dehydrated medium: Straw coloured, free flowing powder
Prepared medium: White coloured gel

Quality control

Positive controls: Expected results
Salmonella enteritidis ATCC® 13076 * Good growth, purple colonies
Salmonella poona NCTC 4840 * Good growth, purple colonies
Negative controls:
Escherichia coli ATCC® 25922 * Growth, blue colonies
Pseudomonas aeruginosa ATCC® 27853 * Inhibited
* This organism is available as a Culti-Loop®

References
1. Gaillot, O. et al. (1999) J. Clin. Microbiol. 37: 762-765.
2. Rambach, A. (1990) Appl. Environ. Microbiol. 56: 301-303.
3. Gruenewald, R. (1991) J. Clin. Microbiol. 29: 2354-2356.

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