Brilliant green lactose bile broth

A further test is done to confirm the presumptive test result this is called the confirmed test. The theory behind this test uses the property of the coliforms to ferment lactose even in the presence of a green dye. Noncoliform organisms cannot ferment lactose in the presence of this dye. The growth medium is called brilliant green lactose bile broth. A wire loop from the positive presumptive test is inoculated into fermentation tubes containing the broth. As in the presumptive test, the tubes are incubated at 35 + 0.5°C. Liberation of gases within 24 to 48 3 hours indicates a positive confirmed test. 

Confirmed test— A further test for the cohform group proceeding from the presumptive test where evolution of gases within 24 to 48 + 3 hours in the presence of a brilliant green lactose bile broth from samples incubated at 35 + 0.5°C indicates a positive test. 

Brilliant green lactose bile broth (for total coliforms) 35°C-37°C + 0.5°C for 24- 8 h Gas production in Durham tubes [2,67]... 

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