One milliliter of the indicator strain (with approximately
5105 cfumL1), cultured in MRS broth for
24 h at 30 1C, was inoculated into 15mL of semisolid
MRS agar (MRS broth plus 0.7% bacteriological agar)
maintained at 45 1C and the resultant mixture was
poured into a Petri dish. After solidification of the agar,
wells 5mm in diameter were cut into it, and 50 mL of
supernatant fluid from a culture of the strain under test,
obtained as indicated below, was added to each well.
The plates were examined for inhibition after incubation
at either 30 or 37 1C for 24 h.