title: [Reductive dechlorination of chlorophenols by an anaerobic mixed culture].
abstract: In this study, we investigated the potential for reductive dechlorination of chlorophenols by municipal sewage sludge acclimated to 2,4-dichlorophenol (2,4-DCP) and 3,4-dichlorophenol (3,4-DCP). The optimal temperature and pH for dechlorination of 2,4,6-trichlorophenol (2,4,6-TCP) were 30 degrees C and 7.2. Dechlorination of 2,4,6-TCP was inhibited by sulfate, nitrate, or ferric (III), but was increased by manganese (IV) except that product of 2,4-DCP was accumulated. Organic substrates such as pyruvate or acetate did not influence dechlorination of 2,4,6-TCP, but increased dechlorination of 2,4-DCP; nevertheless lactate showed no influence on dechlorination. When glucose was added as substrate, only 20% of 2,4,6-TCP dechlorination was found. Addition of methanogenesis inhibitor 2-bromoethane sulfonate did not influence dechlorination, but addition of eubacteria inhibitor vancomycin showed no dechlorination activity at the first few days, and finally complete transformation and accumulation of 2,4-DCP occurred. Because mixed culture was from Di-Hwa Wastewater Treatment Plant, adding the same water as culture medium was found to increase the dechlorination of 2,4,6-TCP and its product 2,4-DCP. Dechlorination by adding wastewater of Petroleum Corporation was also increased, especially for 2,4-DCP product, but only 7% of 2,4,6-TCP dechlorination was found after incubation with Hou-Chin river water for 14 days.
authors.affiliation: Department of Microbiology, Soochow University, Taipei, Taiwan, Republic of China.
authors.forename: B V
authors.initials: BV
authors.lastname: Chang
authors.forename: K S
authors.initials: KS
authors.lastname: Chen
authors.forename: S Y
authors.initials: SY
authors.lastname: Yuan
mesh_terms: D001421:Bacteria, Anaerobic / Q000378:metabolism*; D002733:Chlorophenols / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D010084:Oxidation-Reduction; D013696:Temperature
chemical_list: D002733:Chlorophenols