MacConkey Agar

Pain pink red powder, free-flowing, homogeneous 5.0% solution, soluble in purified water upon boiling. Solution is pain yellow.

Identity Specifications

Dehydrated Appearance	Pain pink red powder, free-flowing, homogeneous
Solution	5.0% solution, soluble in purified water upon boiling. Solution is pain yellow.
Prepared Appearance	Reddish purple, slightly opalescent
Reaction of 5.0% Solution at 25C	pH 7.2 ± 0.4

Cultural Response

Prepare the medium per label directions. Inoculate and incubate at 35 ± 2C for 18-24 hours (and 40-48 hours for E. coli).

Escherichia coli	Partial inhibition, 2-3 zone growth，colony peach, with acid precipitation.
Shigella bogdii Shigella sonnei Shigella flexneri	1-3 zone growth, colony diameter≥1.6mm, colorless, opalescent. Circular.
Enterobacter aerogenes	good growth, colorless opalescent circular colony.
Salmonella sp Salmonella typhimurium	1-4 zone growth, colony diameter1.7-2.0mm，opalescent circular.
Staphylococcus aureu	Growth, pink colony
Enterococcus  faecalis	Partial inhibition
Mixture culture	Streak inoculation of Escherichia coli and Salmonella typhimurium  with ratio 1:1, typical Salmonella typhimurium can be seperated.

Formulae

Approximate Formula* Per Liter

                          Peptone ....................................................... 17.0 g

                          Proteose Peptone ......................................... 3.0 g

                          Lactose ....................................................... 10.0 g

                          Sodium Chloride ............................................ 5.0 g

                          Agar ............................................................. 11.0 g

                          Neutral Red ............................................... 0.025 g

                          Bile Salts ....................................................... 5.0 g

Usage

Sepeartion of enterpathogen as well as enterococcal.

MacConkey Agar