MacConkey agar


Mac·Con·key a·gar

(mă-kon'kē), medium containing peptone, lactose, bile salts, neutral red, and crystal violet, used to identify gram-negative bacilli and characterize them according to their status as lactose fermenters. Fermenters appear as pink colonies whereas nonfermenters are colorless.

MacConkey agar

A differential and selective growth medium used to isolate and identify gram-negative bacilli, often enteric pathogens, based on fermentation or lack of fermentation of a sugar added to the media. MA is peptone-based and contains bile salts and crystal violet (which inhibit the growth of gram-positive organisms), a sugar (usually lactose) and a pH indicator, allowing differentiation of lactose-fermenting (indicated by pink colonies, e.g., Escherichia coli) and non-lactose-fermenting (colourless colonies, e.g., Proteus mirabilis) bacteria.

Mac·Con·key agar

(mă-kongk'ē ā'gahr) Medium containing peptone, lactose, bile salts, neutral red, and crystal violet; used to recover gram-negative bacilli and characterize them according to their ability to ferment lactose. Fermenters appear as red colonies, whereas nonfermenters are colorless.

MacConkey,

Alfred Theodore, English bacteriologist, 1861-1931. MacConkey agar - a medium used to identify gram-negative bacilli and characterize them according to their status as lactose fermenters. Synonym(s): MacConkey mediumMacConkey medium - Synonym(s): MacConkey agar