Microbial dynamics in a continuous stirred tank bioreactor exposed to an alternating sequence of organic compounds.
Microbial dynamics during aerobic biodegradation of an alternating mixture of organic compounds was investigated experimentally in a continuous stirred tank bioreactor (CSTB). A mathematical model describing this system was developed and tested using the experimental results. A model microbial culture consisting of Pseudomonas sp. JS150, a monochlorobenzene (MCB) degrader, and Xanthobacter autotrophicus GJ10, a 1,2-dichloroethane (DCE) degrader, each with exclusive degradation capabilities, was used. The CSTB was inoculated with both microbial strains and exposed to an alternating sequence of the two compounds at noninhibitory concentrations. Concentrations of each microbial strain, of each organic compound, and of degradation product evolved, as well as specific microbial activities via oxygen uptake tests, were monitored. Reduction of the residual DCE discharged from the bioreactor after an MCB to DCE transition was successfully achieved by continuously feeding a low flow of a concentrated solution of both compounds.
Ferreira Jorge
R M
RM
Department of Chemical Engineering and Chemical Technology, Imperial College of Science, Technology and Medicine, London SW7 2BY, UK.
Livingston
A G
AG
D000465:Algorithms; D001673:Biodegradation, Environmental; D019149:Bioreactors; D002722:Chlorobenzenes / Q000378:metabolism*; D005025:Ethylene Dichlorides / Q000378:metabolism*; D008954:Models, Biological; D010100:Oxygen / Q000378:metabolism; D011157:Population Dynamics; D011549:Pseudomonas / Q000254:growth & development* / Q000378:metabolism; D014874:Water Pollutants, Chemical / Q000378:metabolism*; D020584:Xanthobacter / Q000254:growth & development* / Q000378:metabolism
D002722:Chlorobenzenes; D005025:Ethylene Dichlorides; D014874:Water Pollutants, Chemical; C024565:ethylene dichloride; C031294:chlorobenzene; D010100:Oxygen