Biofilm formation was measured under static conditions as described
elsewhere (Merritt et al., 2005). Briefly, 96-well polystyrene microtiter
plates (Greiner Bio-One) were filled with 200 μl of either MRS,
AOAC, mTSB, BHIMnG or PMM7 and inoculated with 1% (v/v) of an
overnight grown culture (18 h at 30 °C) containing 8.5 log colonyforming units (cfu perml) (18 h). Themicrotiter plates were incubated
for either 24, 48 or 72 h at 30 °C and biofilm formation was quantified
using crystal violet (CV) assay and by plate counting to determine the
number of culturable cells in the biofilm.