Exam 2 Selective Media Flashcards
(28 cards)
MSA selects for:
Staphylococci and some other Gram-positive species that can withstand high salt concentrations
MSA inhibits:
Gram-negative growth
Inhibitor in MSA
Sodium Chloride
MSA substrate
Mannitol
MSA Indicator
Phenol Red
Positive result on MSA
Media turns yellow if mannitol fermentation occurs (generally S. aureus)
Negative result on MSA
Media is red
MAC selects for:
Gram-negative enteric species
MAC inhibits:
Gram-positive non-enteric species
MAC Inhibitor
Bile Salts and Crystal Violet
MAC substrate
Lactose
MAC Indicator
Neutral Red
MAC Positive result
Pink/red growth if lactose fermentation occurs
MAC negative result
Colorless or yellow growth if no lactose fermentation occurs
EMB selects for:
Gram-negative enteric species
EMB inhibits
Gram-positive species
EMB inhibitor
Eosin Y and Methylene Blue
EMB substrate
lactose
EMB indicator
Eosin Y and Methylene Blue
EMB positive results
Growth with green sheen means vigorous lactose fermentation; purple/pink growth means weak lactose fermentation
EMB negative results
Colorless growth means no lactose fermentation
HE selects for
Gram-negative enteric species
HE inhibits
Gram-positive species
HE inhibitor
Bile salts
