Ar. Pedersen et E. Arvin, The function of a toluene-degrading bacterial community in a waste gas trickling filter, WATER SCI T, 39(7), 1999, pp. 131-137
The function of a community of toluene-degrading bacteria in a biofilm syst
em was investigated with regard to growth and toluene degradation in order
to investigate substrate interactions in the community. This was done by th
e combination of experimental observations using a specific oligonucleotide
16S ribosomal RNA probe targeting the toluene-degrading species Pseudomona
s putida, and by computer simulations (AQUASIM) of the biofilm growth based
on a food web model. Biofilms were taken from a lab-scale trickling filter
for treatment of toluene-polluted air. The biofilm growth and the activity
of P. putida, a representative of the toluene-degrading species in the bio
film which have been described previously (Pedersen et al., 1997) were simu
lated. The simulation indicated that the volume fraction of the toluene deg
raders in the biofilm decreased from 12% to only 2% (11% of dry weight) dur
ing two weeks. In spite of the low fraction in the biofilm, the toluene deg
raders supported growth of the dominating part of non-toluene-degrading het
erotrophs in the biofilm, as toluene was the sole carbon source supplied to
the system. The maximum intrinsic growth rate of P. putida in the biofilm
was only 20% of the maximum growth rare determined in a batch experiment wi
th suspended P. putida cells. (C) 1999 IAWQ Published by Elsevier Science L
td. All rights reserved.