K.R.A.N.E.P. Agar Base

K.R.A.N.E.P. Agar Base is recommended for selective enumeration of total Staphylococci from foodstuffs. The name K.R.A.N.E.P. Agar comes from the initial letters of its main diagnostic, selective and stimulatory agents like Kalium-Rhodanid-Actidione-Natriumazid-Eigelb-Pyruvate. The medium is selective for the detection of Staphylococci due to the presence of potassium thiocyanate and mannitol. Sodium pyruvate and egg yolk emulsion added to the medium serve as growth enhancer and diagnostic agent respectively. Cycloheximide inhibits most of the yeasts and moulds. moulds. Inclusion of sodium azide helps to inhibit the accompanying aerobic organisms like Bacillus species, which interfere with the cultivation of Staphylococci. Colonies typical for S.aureus but without an egg yolk reaction should also be tested for coagulase and if positive their identity should be confirmed by further tests.