MSA Flashcards
1
Q
MSA stands for what?
A
Mannitol Salts Agar
2
Q
What does MSA selectively culture?
A
Staphylococci bacteria
3
Q
What does MSA differentiate?
A
Staphylococci aureus
4
Q
What is the selective ingredient?
A
High salt concentration
5
Q
What are the different ingredients?
A
Mannitol and penal red
6
Q
Explain how mannitol and phenol red react to create a differentiating property
A
Mannitol is only fermented by S. aureus. When it’s fermented it is broken down and releases acidic by-products in the process, these acids react with phenol red. When acids are released phenol red changes from a red to yellow color.
