Salmonella

Description

Use and description:

For the selective differentiation of salmonella spp. from other pathogenic enterobacteriaceae from food and clinical specimens. Gram-positive bacteria are inhibited by bile salts, citrate. Salmonella spp. will grow as magenta colonies, Enterobacter spp. will grow as deep blue colonies.

Composition per liter:

Peptones………………………………………. 7.0 g

L-lysine  ………………………………………..0.5 g

L-cystine ……………………………………….0.1 g

Beef Extract ……………………………………5.0 g

Chromogenix mix……………………………0.30 g

Agar…………………………………………  …12.0 g

Yeast extract …………………………………..5.0 g

Xylose ………………………………………….1.75 g

Final pH of the ready to use medium:   7.0 ± 0.2

Medium preparation:

Add 31,7 grams of dehydrated culture medium to 1 liter of distilled water, and allow to soak for 10 minutes. Swirl to mix, then bring to the boil and autoclave at 121 C for 15 minutes. Dry the surface before incubation.

Quality specifications:

Dehydrated medium:  homogeneous, beige fine powder.

Ready to use medium:  straw coloured agar, clear to very slightly opalescent.

Microbiological response:

Storage:

Dehydrated medium should be stored between 10 to 25^oC. Once opened, place the container in a dark, dry place. The dehydrated medium should not be used if there is any lump or if color has changed from the original.