MacConkey Agar

Question 1

What is MacConkey Agar selective for?

Answer 1

Gram-negative bacteria

Question 2

What are the key ingredients in MacConkey Agar?

Answer 2

Lactose
Bile salts
Neutral red
Crystal violet

Question 3

Explain the differential properties of MacConkey Agar

Answer 3

Gram-negative lactose fermenters will turn a red/pink color. Non-lactose fermenters will stay the same color or become the color of the media

Question 4

How are MacConkey and EMB Agar similar?

Answer 4

They both are selective for gram-negative bacteria and differentiate based on lactose fermentation