Aerobic dechlorination of cis- and t

Aerobic dechlorination of cis- and trans-dichloroethenes by some indigenous bacteria isolated from contaminated sites in

Abstract：The innate toxicity of dichloroethenes(DCEs) and their tendency to be reduced to vinyl chloride(VC)(a known human carcinogen) is a cause for environmental concern. Aerobic bacteria capable of growth on cis- and trans-DCEs as sole carbon and energy sources were isolated by enrichment culture technique and identified to belong to the genera; Bacillus, Pseudomonas and Acinetobacter. Axenic and mixed cultures of the bacterial isolates utilized DCEs at concentrations above the maximum contaminant level allowable in drinking water by the Environmental Protection Agency. Their specific growth rate constant ranged significantly(P<0.05) between 0.346-0.552 and 0.461-0.667 d-1; while the maximum specific substrate utilization rate ranged significantly(P<0.05) between 20.01-29.79 and 31.40-42.83 nmol h-1 (mg of protein)-1 in cis- and trans- DCE, respectively. The optimum growth was observed at 30℃ and at a pH of 7.0 with up to 96% of the stoichiometric-expected chloride released. Serial adaptation positively affected the growth yields and dehalogenase activities of the organisms with multiple antibiotic patterns also demonstrated by the isolates. These findings therefore indicated the important roles that these organisms may play in the bioremediation of sites polluted with chlorinated ethene compounds in Africa.作 者：Ademola O.Olaniran    Dorsamy Pillay    Balakrishna Pillay  作者单位：Ademola O.Olaniran(Department of Microbiology, University of Durban-Westville, P. Bag X54001, Durban 4000, South Africa;Department of Microbiology, Faculty of Science, Obafemi Awolowo University, Ile-Ife, Nigeria)

Dorsamy Pillay(Department of Biotechnology, Durban Institute of Technology, P. O. Box 1334, Durban 4000, South Africa)

Balakrishna Pillay(Department of Microbiology, University of Durban-Westville, P. Bag X54001, Durban 4000, South Africa) 

期 刊：环境科学学报（英文版）  ISTICSCI  Journal：JOURNAL OF ENVIRONMENTAL SCIENCES 年，卷(期)：2004, 16(6) 分类号：X131.3 Keywords：aerobic    bioremediation    dichloroethenes    dehalogenase    polluted site