Biofilm population dynamics in a trickle-bed bioreactor

The biodegradation of polyalkylated benzenes (Solvesso 100(R)) From waste air in a trickle-bed bioreactor was studied. The immobilized mixed population was analyzed by in-situ hybridization using group-specific fluorescence labeled rRNA-target oligonucleotides. It was shown that the growth conditions of an immobilized system are not comparable to those of a submerged culture. Variations of the concentrations of the alpha-, beta-, and gamma-subclasses of the proteobacteria of the biofilm population were measured. A significant increase of the biodegradation rate and, thus, of the activity of the microbial mixed population present in the biofilm was observed by applying a forced cyclical substrate time function. (C) 1998 IAWQ. Published by Elsevier Science Ltd.