- DCA agar
It is particularly useful for the isolation of organisms that cause bacilliary dysentery, salmonella strains that cause food poisoning and Salmonella Paratyphi. It is not so selective for Salmonella Typhi. This growth medium is inhibitory to most gut bacteria, in particular species of the genus Proteus, although these species do survive on DCA agar. It is therefore essential that suspected pathogens must be subcultured on a less inhibitory medium prior to identification. Salmonella spp appear to be yellow or colourless colonies, often with a dark centre. As there are many bacteria that also look like Salmonella on DCA, it is widely recommended that more selective agars are used for the identification of Salmonella, namely xylose lysine deoxycholate (XLD) agar. This growth medium is heat-sensitive and should be poured and cooled as soon as possible after addition of the deoxycholate, otherwise it tends to become very soft and difficult to handle. It has a pH of approximately 7.3, and when poured and cooled, appears light to dark pink in colour.
DCA agar contains:
'Lab Lemco' powder 5g/l Peptone 5g/l Lactose 10g/l Sodium citrate 8.5g/l Sodium thiosulfate 5.4g/l Ferric citrate 1g/l Sodium deoxycholate 5g/l Neutral red 20 mg/l Agar 12g/l Growth media / agar plates Selective mediaAlphaproteobacteriaBrucella abortus (Brucella agar)Betaproteobacteria Differential media Fungal media Nonselective media Other/ungrouped media
Wikimedia Foundation. 2010.
Look at other dictionaries:
DCA — deoxycholate citrate agar; deoxycholic acid; desoxycorticosterone acetate; dichloroacetate; directional color angiography; directional coronary atherectomy * * * desoxycorticosterone acetate … Medical dictionary
DCA — • deoxycholate citrate agar; • deoxycholic acid; • desoxycorticosterone acetate; • dichloroacetate; • directional color angiography; • directional coronary atherectomy … Dictionary of medical acronyms & abbreviations
MacConkey agar — with lactose (left) and non lactose (right) fermenters … Wikipedia
Chocolate agar — showing Francisella tularensis colonies … Wikipedia
Cysteine lactose electrolyte deficient agar — A clear CLED agar plate after cultivation … Wikipedia
Thayer-Martin agar — Comparison of two culture media types used to grow Neisseria gonorrhoeae bacteria. Known as overgrowth, note that the non selective chocolate agar medium on the left, due to its composition, allowed for the growth of organismal colonies other… … Wikipedia
Cetrimide agar — is a type of agar used for the selective isolation of the gram negative bacteria, Pseudomonas aeruginosa. As the name suggests, it contains cetrimide, which is the selective agent against alternate microbial flora. Cetrimide also enhances… … Wikipedia
Nutrient agar — is a microbiological growth medium commonly used for the routine cultivation of non fastidious bacteria. It is useful because it remains solid even at relatively high temperatures. Also, bacteria grown in nutrient agar grows on the surface, and… … Wikipedia
Mueller-Hinton agar — Colonies of Burkholderia pseudomallei on Müller Hinton agar after 72 hours incubation. Müller Hinton agar is an microbiological growth medium that is commonly used for antibiotic susceptibility testing. It is also used to isolate and maintain… … Wikipedia
Cystine tryptic agar — (CTA), also known as cystine trypticase agar, is a growth medium used for the identification of microorganisms. It can be used to determine if organisms can ferment various carbohydrates, including maltose, lactose, and sucrose. This… … Wikipedia