Fig. 2.

The inhibitory effect of d-amino acids on biofilm growth is similar on different substrates. Biofilms formed equally on polystyrene, epoxy, and glass substrates after 24 h of growth and did not form in the presence of d-amino acids (+ D-aa), suggesting the mechanism of action of d-amino acids is unrelated to initial surface attachment. Biofilm attached to the surface appears white in these unstained samples. For the glass and epoxy substrates, cover glass and molded epoxy were submerged in medium in 6-well plates. For growth on polystyrene, the bottom of the well was used as the substrate.