Description
In 1986 Tryptone Soya Broth containing 10% sodium chloride was replaced in the Australian Standard by Giolitti-Cantoni Broth.
Giolitti-Cantoni Broth AM 64 is based on the formulation of Giolitti and Cantoni. It contains the same selective agents as Baird-Parker Agar, but at different concentrations. Lithium chloride inhibits Gram negative lactose fermenting organisms and Gram positive organisms are inhibited by the combination of potassium tellurite and glycine. Mannitol and sodium pyruvate enhance the growth of Staphylococcus aureus and sodium pyruvate aids the recovery of stressed cells. Anaerobic conditions are maintained by the use of fresh or re-heated broth and the application of a paraffin wax or agar seal after inoculation of the tubes. These conditions increase selectivity. Reduction of potassium tellurite to tellurium results in blackening of the broth.
Giolitti-Cantoni Broth is recommended for detection of very low numbers of Staphylococci in baby formula and weaning foods where 1 gram aliquots of the sample are required to be free of the organism.
