Question

A. Mannitol salts Uses: Selective media for Staphylococcus aureus. This medium contains 7.5% salt, which is inhibitory to most bacteria other than staphylococci. While most species of Staphylococcus are capable of growing in this high salt concentration, S. aureus is also capable of fermenting the carbohydrate mannitol. Mannitol Glucose Mannitol Salt Agar (selective/differential) • Selective medium for the isolation of staphylococci. • The high concentration of NaCl (7.5%) selects for members of the genus Staphylococcus, since they can tolerate high saline levels. • Organisms from other genera may grow, but they typically grow very weakly. • Also contains the sugar mannitol and the pH indicator phenol red. • If an organism can ferment mannitol, an acidic byproduct is formed that will cause the phenol red in the agar to turn yellow. A: Staphylococcus aureus showing fermentation of mannitol (yellow medium). B: Staphylococcus epidermidis showing growth but no fermentation of mannitol (pink medium). C: Escherichia coli showing no growth.

          A. Mannitol salts

Uses: Selective media for Staphylococcus aureus. This medium contains 7.5% salt, which is inhibitory to most bacteria other than staphylococci. While most species of Staphylococcus are capable of growing in this high salt concentration, S. aureus is also capable of fermenting the carbohydrate mannitol.

Mannitol
Glucose

Mannitol Salt Agar (selective/differential)
• Selective medium for the isolation of staphylococci.
• The high concentration of NaCl (7.5%) selects for members of the genus Staphylococcus, since they can tolerate high saline levels.
• Organisms from other genera may grow, but they typically grow very weakly.
• Also contains the sugar mannitol and the pH indicator phenol red.
• If an organism can ferment mannitol, an acidic byproduct is formed that will cause the phenol red in the agar to turn yellow.

A: Staphylococcus aureus showing fermentation of mannitol (yellow medium).

B: Staphylococcus epidermidis showing growth but no fermentation of mannitol (pink medium).

C: Escherichia coli showing no growth.

A. Mannitol salts

Uses: Selective media for Staphylococcus aureus. This medium contains 7.5% salt, which is inhibitory to most bacteria other than staphylococci. While most species of Staphylococcus are capable of growing in this high salt concentration, S. aureus is also capable of fermenting the carbohydrate mannitol.

Mannitol
Glucose

Mannitol Salt Agar (selective/differential)
• Selective medium for the isolation of staphylococci.
• The high concentration of NaCl (7.5%) selects for members of the genus Staphylococcus, since they can tolerate high saline levels.
• Organisms from other genera may grow, but they typically grow very weakly.
• Also contains the sugar mannitol and the pH indicator phenol red.
• If an organism can ferment mannitol, an acidic byproduct is formed that will cause the phenol red in the agar to turn yellow.

A: Staphylococcus aureus showing fermentation of mannitol (yellow medium).

B: Staphylococcus epidermidis showing growth but no fermentation of mannitol (pink medium).

C: Escherichia coli showing no growth.

Added by Kathryn M.

Question

Please give Ace some feedback