This is a liquid medium suitable for the selective isolation and presumptive identification of Methicillin Resistant Staphylococcus aureus (MRSA). The medium is made selective for MRSA through the addition of a number of antibiotics to suppress both Gram –ve and Gram +ve organisms other than staphylococci. As most strains of Staphylococcus aureus ferment D-Mannitol to produce acid this is detected by the change of colour of the medium from red to yellow/amber due to the presence of the Phenol Red Indicator.
NB: It is recommended that cultures giving a presumptive positive result should be sub-cultured to a selective agar medium (PP3059 Colorex MRSA). Any resulting colonies should be subjected to further biochemical testing to confirm the full identity of the isolate.