Acta Chimica Slovaca (ACS) publishes papers on fundamental and applied aspects of chemistry, biochemistry, chemical technology, chemical engineering and process control, biotechnology and food technology. Welcome are also topics which include chemical aspects of materials, physical chemistry and chemical physics, analytical chemistry, macromolecular chemistry and biomedical engineering.

Four-compartmental kinetic model of the simultaneous processes occurring throughout biodegradation of polychlorinated biphenyls in the active bacterial cell suspension

Branislav Vrana, Katarína Dercová * a, Štefan Baláž b, Roman Tandlich c

Water Research Institute, Nábr. arm. gen. L. Svobodu 5, 812 49 Bratislava, Slovakia
a Department of Biochemical Technology, Faculty of Chemical and Food Technology, Slovak University of Technology, Radlinského 9, SK-81237 Bratislava, Slovakia
b Department of Pharmaceutical Sciences, College of Pharmacy, North Dakota State University, Sudro Hall 108, Fargo, ND-58105, USA
c Department of Biochemistry, Microbiology and Biotechnology, Faculty of Science, Rhodes University, Grahamstown 6140, Republic of South Africa

E-mail: *

Abstract: Kinetics of distribution of polychlorinated biphenyls (PCBs) in an active bacterial suspension of Pseudomonas stutzeri was studied by monitoring the evaporated amounts and the concentration remaining in the liquid medium containing the biomass of the degrader bacterium. A model considering biosorption, evaporation, and primary biodegradation of individual PCB congeners was constructed using the methods of subcellular toxicokinetics. The time hierarchy of the underlying processes (uptake/release of the congeners to/from biomass is much faster than evaporation and degradation) allowed for construction of a simplified disposition function, i.e. the time dependence of the intra- and extracellular PCB concentrations. The resulting model was fitted to the experimental data, with the parameters characterising biosorption and evaporation determined in separate experiments. In this way, the biodegradation rate constants were determined for individual congeners of the technical PCB mixture DELOR 103. Biodegradability decreases with increasing number of chlorines in the molecule, especially if they are located in the ortho- and para- positions. On the other hand, the increasing number of free 2,3-positions or their equivalents on the biphenyl skeleton leads to an increased biodegradability. A quantitative structure-degradability relationship with these variables was formulated for 2- and 3-chlorinated congeners.

Keywords: biosorption, biodegradation, evaporation, polychlorinated biphenyls

Full paper in Portable Document Format: acs_0029.pdf

Acta Chimica Slovaca, Vol. 1, No. 1, 2008, pp. 329—349