A PCB dechlorinating community occurring in a contaminated sediment of the Venice lagoon was enriched and characterized under slurry-phase anaerobic conditions by using sterile sediment and water coming from the site in the presence of 5 spiked coplanar PCB congeners at 500 mg/kg. In the primary microcosm, the dechlorination activity started after a five-month lag phase, after which all spiked PCBs were markedly transformed into lower chlorinated congeners with a dechlorination rate of 112±26 Cl/kg of sediment/week. No lag phase and significantly higher dechlorination rates, as well as a marked increase in sulfate-reduction and a progressive decrease in the methanogenic activity, were detected after serial transfers of the culture. Consistently, T-RFLP analysis of 16S rDNA showed a progressive reduction in the complexity of the archaeal community and an enrichment of several eubacterial taxons during the culture transfer process. Preliminary cloning and sequencing operations indicate that sulfate-reducing bacteria are among the forms mostly enriched in the last enrichment culture. This suggests that such a group of bacteria contributes to the PCB dechlorination activity detected.
Titolo: | Enrichment and characterization of a PCB dechlorinating community in a contaminated sediment of Venice lagoon | |
Autore/i: | ZANAROLI, GIULIO; J. R. Perez Jimenez; L. Y. Young; FAVA, FABIO | |
Autore/i Unibo: | ||
Anno: | 2005 | |
Titolo del libro: | Atti del 7° Convegno FISV - Federazione Italiana Scienze della Vita | |
Pagina iniziale: | D10.2 | |
Pagina finale: | D10.2 | |
Abstract: | A PCB dechlorinating community occurring in a contaminated sediment of the Venice lagoon was enriched and characterized under slurry-phase anaerobic conditions by using sterile sediment and water coming from the site in the presence of 5 spiked coplanar PCB congeners at 500 mg/kg. In the primary microcosm, the dechlorination activity started after a five-month lag phase, after which all spiked PCBs were markedly transformed into lower chlorinated congeners with a dechlorination rate of 112±26 Cl/kg of sediment/week. No lag phase and significantly higher dechlorination rates, as well as a marked increase in sulfate-reduction and a progressive decrease in the methanogenic activity, were detected after serial transfers of the culture. Consistently, T-RFLP analysis of 16S rDNA showed a progressive reduction in the complexity of the archaeal community and an enrichment of several eubacterial taxons during the culture transfer process. Preliminary cloning and sequencing operations indicate that sulfate-reducing bacteria are among the forms mostly enriched in the last enrichment culture. This suggests that such a group of bacteria contributes to the PCB dechlorination activity detected. | |
Data prodotto definitivo in UGOV: | 11-ott-2005 | |
Appare nelle tipologie: | 4.02 Riassunto (Abstract) |