KM0050 – Deoxycholate Citrate Agar (DCA) Hynes

//KM0050 – Deoxycholate Citrate Agar (DCA) Hynes

KM0050 – Deoxycholate Citrate Agar (DCA) Hynes

This is a selective medium for the isolation of Salmonella spp. and Shigella spp. from clinical specimens and environmental samples. This formulation was developed by Hynes through a modification of Leifson’s DCA medium.
The peptone provides the required carbon, nitrogen and vitamins. Lactose is a fermentable carbohydrate and neutral red is a pH indicator. Sodium thiosulphate and ferric citrate are used to detect hydrogen sulphide production indicated by the black centred colonies of hydrogen sulphite positive organisms. Sodium desoxycholate and sodium citrate inhibit most Gram-positive organisms.

SKU: KM0050 Category:

Additional Information

Shelf Life (days)

Storage Temp (°C)

Dehydrated Medium Appearance

Prepared Medium Appearance

Dehydrated Medium Colour

Prepared Medium Colour

Dehydrated PH

Prepared PH

Product Description

Organisms Ref. No Result
Salmonella typhimurium NCTC 12023 Growth, translucent colonies with black centre
Shigella sonnei NCTC 8574 Growth, colourless/pale pink colonies
Enterococcus faecalis NCTC 12697 Inhibited

 

Formula*

g/L
Peptone 10.0
Lactose 10.0
Sodium desoxycholate 5.0
Sodium citrate 8.5
Sodium thiosulphate 5.4
Ferric citrate 1.0
Neutral red 0.02
Agar 12.0
Total 52.0
*Adjusted/supplemented as required to meet performance requirements

Preparation

Suspend 52g of the medium in one litre of deionised / purified water. Allow the medium to soak whilst mixing for 10 minutes. Heat with frequent agitation and boil for one minute to completely dissolve the medium. DO NOT AUTOCLAVE this medium. Cool to 45-50°C and aseptically dispense into appropriate sterile containers.