The culture medium complies with the requirements of the ISO Standard 16654 for the detection of Escherichia coli (E. coli) serotype 0157:H7 in foods as well as with the methods of FDABAM for the isolation of enterohemorrhagic E. coli (EHEC).
Mode of Action
The nutrient substrates contained in mTSB broth provide favourable growth conditions. The mixture of bile salts No. 3 and Novobiocin suppresses the growth of the Gram-positive microbial flora.
Typical Composition (g/litre)
Peptone from caseine 17.0; peptone from soymeal 3.0; sodium chloride 5.0; bile salts No. 3 1.5; D(+)-glucose 2.5; di-potassium hydrogen phosphate 4.0; novobiocin 0.02.
Suspend 33 g in 1 litre of demin. water; autoclave (15 min at 121°C).
pH: 7.3 ± 0.2 at 25 °C.
The prepared broth is clear and yellowish. The broth is stable for up to 6 month when stored at +2 – +8 °C.
Experimental Procedure and Evaluation
Inoculate mTSB Broth with the sample material (usually add 25g test portion of the sample to 225ml of broth).
Incubation: 18 to 24 h at 37 °C or 41.5 °C. Incubation temperature depends on standard used.
Afterwards about 0.1 ml of the broth is streaked on the dry surface of a E. coli 0157:H7 Selective Agar, e.g. Fluorocult® E.coli 0157:H7 Agar, SMAC Agar or CT-SMAC Agar in a way, that single colonies can be well isolated