MacConkey Agar w/ 0.15% Bile Salts, CV and NaCl

Principle

• MacConkey agar is composed of peptone, protease peptone, lactose, bile salt, sodium chloride, neutral red, crystal violet, and agar.
• Peptone and protease peptone provide nitrogen and other nutrients necessary for the growth of microorganisms.
• Lactose is a carbon source and plays an important role in the selection of lactose-fermenting microbes.
• Bile salt and crystal violet are selective agents, that inhibit the growth of gram-positive organisms. Neutral red is a pH indicator dye. Agar is the solidifying agent.
• When lactose is fermented, acid is produced which results in bile salt precipitation. Since the lactose fermenting colonies of coliform bacteria are pink in color and may be surrounded by a zone of bile precipitation.
• While the bacteria that do not ferment lactose remain colorless. 

Use:

Recommended for isolation and differentiation of lactose fermenting and lactose non-fermenting gram-negative enteric bacilli from pharmaceutical, clinical, and non-clinical samples, dairy, food, and water samples.