Blood Agar Base
Non-selective
No fermentable carbohydrates
No indicator
Differential (low selectivity) agar media
Eosin Methylene Blue (EMB)
Levine's EMB
MacConkey
Desoxycholate
Eosin Methylene Blue (EMB)
Gram pos. bacteriostatic agent: Eosin Y + Methylene Blue
Ferm Carb: Lactose + Sucrose
Indicator: Eosin + Methylene Blue
Colony color:
Fermentor- Dk purple, metal green sheen
Non-ferm- colorless
Levine's EMB
Gram pos bacteriostat agent: Eosin Y + methylene blue
Ferm carb: lactose
Indicator: Eosin Y + Methylene Blue
Colony Color:
Fermentor- Dk purple metal green sheen
Non-ferm- colorless
MacConkey
Gram pos. bacteriostat. agent: crystal violet + bile salts
ferm carb: lactose
indicator: neutral red
Colony color:
fermentor- red/pink
non-ferm - colorless
Desoxycholate
Gram pos. bacteriostat agent: bile salts
ferm carb: lactose
indicator: neutral red
colony color:
fermentor- brick red/pink
non-ferm- colorless
Moderately selective agar media
Select for Salmonella and Shigella
Xylose Lysine Deoxycholate (XLD)
Salmonella-Shigella (SS)
Desoxycholate-Citrate
Hektoen Enteric (HE)
Xylose Lysine Deoxycholate (XLD)
bacteriostat agent: bile salts
ferm carb: lactose, xylose, sucrose
Indicator: phenol red + H2S indicator (non ferments)
Colony color
fermentor- yellow
non ferm- pink to red
Salmonella-Shigella (SS)
Agent: bile salts
ferm carb: lactose
indicator: neutral red + H2S indicator
colony color
ferm- red
non ferm- colorless
Desoxycholate-Citrate
Agent: bile salts
ferm carb: lactose
indicator: neutral red
colony color
ferm-red
non ferm- colorless
Hektoen Enteric (HE)
Agent: bile salts
ferm carb: lactose, salicin, sucrose
indicator: bromothymol blue and H2S indicator
colony color
ferm- yellow/orange
non-ferm- green or blue-green
Highly selective agar media
Selects for Salmonella
Brilliant Green
Brilliant Green
agent: brilliant green
ferm carb: lactose and sucrose
indicator: phenol red
colony color:
ferm- yellow/green
non ferm- pink/white with red surroundings