Illustration of the nCDFF and sample wells of the CDFF and nCDFF in comparison.

<p>Illustration (not to scale) of the non-constant-depth film fermenter on the right, consisting of a glass vessel and stainless steel end plates with ports for inoculation/sterile culture medium, aeration, sampling and an outlet. The vessel houses a rotating disc with 14 wells containing sample holders with the biomaterial samples. The bacterial suspension or medium, respectively, is continuously exchanged while the disc is slowly rotating. The scraper bar homogeneously distributes the inoculum/medium over the wells and, in addition, wipes off the surplus bacterial suspension/medium from the disc. On the left, the side view of a sample well including sample holder, biomaterial and cultivated biofilm of the CDFF <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0084837#pone.0084837-Bruinsma1" target="_blank">[8]</a> compared to the nCDFF (this study) is shown.