Cometabolic degradation of trichloroethylene by Pseudomonas cepacia G4 in a chemostat with toluene as the primary substrate (1994)

Author(s): Landa AS, Sipkema EM, Weijma J, Beenackers AA, Dolfing J, Janssen DB

  • : Cometabolic Degradation of Trichloroethylene by Pseudomonas-Cepacia G4 in a Chemostat with Toluene as the Primary Substrate

Abstract: Pseudomonas cepacia G4 is capable of cometabolic degradation of trichloroethylene (TCE) if the organism is grown on certain aromatic compounds. To obtain more insight into the kinetics of TCE degradation and the effect of TCE transformation products, we have investigated the simultaneous conversion of toluene and TCE in steady-state continuous culture. The organism was grown in a chemostat,vith toluene as the carbon and energy source at a range of volumetric TCE loading rates, up to 330 mu mol/liter/h. The specific TCE degradation activity of the cells and the volumetric activity increased, but the efficiency of TCE conversion dropped when the TCE loading was elevated from 7 to 330 mu mol/liter/h. At TCE loading rates of up to 145 mu mol/liter/h, the specific toluene conversion rate and the molar growth yield of the cells were not affected by the presence of TCE. The response of the system to varying TCE loading rates was accurately described by a mathematical model based on Michaelis-Menten kinetics and competitive inhibition. A high load of 3,400 mu mol of TCE per liter per h for 12 h caused inhibition of toluene and TCE conversion, but reduction of the TCE load to the original nontoxic level resulted in complete recovery of the system within 2 days. These results show that P. cepacia can stably and continuously degrade toluene and TCE simultaneously in a single-reactor system without biomass retention and that the organism is more resistant to high concentrations and shock loadings of TCE than Methylosinus trichosporium OB3b.

Notes: Times Cited: 51 Cited Reference Count: 32 English Article APPL ENVIRON MICROBIOL PE570

  • Short Title: Cometabolic Degradation of Trichloroethylene by Pseudomonas-Cepacia G4 in a Chemostat with Toluene as the Primary Substrate
  • Alternate Journal: Appl. Environ. Microbiol.
  • Date: September 1994
  • Journal: Applied and Environmental Microbiology
  • Volume: 60
  • Issue: 9
  • Pages: 3368-3374
  • Publisher: American Society for Microbiology
  • Publication type: Article
  • Bibliographic status: Published

Keywords: halogenated aliphatic-compounds; methylosinus-trichosporium ob3b; toxicity; biodegradation; metabolism; kinetics; growth; bioreactor; oxidation; bacteria


Dr Jan Dolfing
Senior Researcher in Environmental Engineering