Quantification of bacteria recovered during simultaneous and sequential co-inoculation biofilm assaysa.

aSimultaneous and sequential co-inoculation biofilm assays were performed in glass column systems packed with polypropylene beads, which constituted the growth support.After 72 h of cultivation, the biofilm cells were detached from the beads and resuspended in PBS. Appropriate dilutions were plated on selective BGA plates containing Gm or Nal and enumerated. Population of cells of each strain (A or B) is expressed as a percentage of the total population of cells recovered.