MacConkey agar

MacConkey agar kdorfman Thu, 01/17/2013 - 19:41

MacConkey Agar

  • Fisher 212122 2 kg (Difco)
  • Krackeler 10-211387 500g (via Sigma)
  • HiMedia MacConkey agar, granulated GM081 (Fisher NC1876763, VWR 95020-204)

to distinguish Lac+ and Lac- bacterial strains.

50 g/L

(If you are going to make more than one bottle, turn on 65C waterbath in tissue culture room)

Turn on the stir-plate heat to 105C.

Withhold 50 mL of water to rinse the mouth of the bottle.

Heat the rest of the water to boiling in the bottle in the microwave.

Measure out the agar mix while the water is heating

Add the stir bar (CAREFULLY!) to the bottle of hot water

Put the bottle on the stir-plate

Add the agar mix to the bottle

Use the reserved water to rinse the granules stuck in the neck down to the liquid.

Stir and heat until granules are completely dissolved.

Cap loosely, wrap with foil, and autoclave.

(If you make more than one bottle, the extras go in the water bath till you are ready to pour)

To make Maconkey agar plates
at mm plate diameter
pour mL per plate
start with: mL hot water
add g Maconkey agar, heat to boiling, stir till dissolved
autoclave for: minutes

leave stir bar in

put bottles on stir plate near sterile hood until handle-able

If you accidentally buy

MacConkey + bile+ CV

MacConkey + bile+ CV kdorfman Mon, 01/08/2024 - 16:00

If you accidentally buy MacConkey without

  • bile salts (1.5 g/L)
  • Crystal violet (0.001g/L)
  • NaCl (5 g/L)
To make Maconkey agar plates
at mm plate diameter
pour mL per plate
start with: mL hot water
add g Maconkey agar (without bile, CV, NaCl)
add g bile salts
add g NaCl
add mL 1% crystal violet solution, heat to boiling, stir till dissolved
autoclave for: minutes