Why is MacConkey Agar commonly used in clinical laboratories to test for gastrointestinal infections?
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MacConkey Agar (MCA) is commonly used in clinical laboratories to test for gastrointestinal infections because it is a selective and differential medium that can isolate and differentiate easily growing Gram-negative bacteria, especially members of the Enterobacteriaceae family . MCA contains bile salts and violet crystals, which inhibit the growth of Gram-positive bacteria, allowing for the selective isolation of Gram-negative bacteria . Additionally, MCA contains lactose and phenol red as indicators, allowing for the differentiation of bacteria based on their ability to ferment lactose. Lactose-fermenting bacteria produce acid, causing the pH indicator to change from orange to bright yellow . This characteristic helps in the identification of specific pathogens, such as Escherichia coli and Salmonella typhi, which are known to ferment lactose . Therefore, MCA is a valuable tool in clinical laboratories for the detection and identification of gastrointestinal pathogens.
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01 Feb 2021 2 Citations | The provided paper does not mention why MacConkey Agar is commonly used in clinical laboratories to test for gastrointestinal infections. |
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| The provided paper does not mention why MacConkey Agar is commonly used in clinical laboratories to test for gastrointestinal infections. | |
| The paper does not provide information on why MacConkey Agar is commonly used in clinical laboratories to test for gastrointestinal infections. |
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