title: Degradation of tributyltin in microcosm using Mekong River sediment.
abstract: The degradation of tributyltin (TBT) and changes of bacterial number and community structures were investigated in microcosms using the sediment collected from the Mekong River, Vietnam. Concentrations of TBT in sediments were less than 0.62 ng/g (dry wt), lower than those reported from other areas. TBT-resistant bacteria were found in the three sampling sites, and the occurrence rates were 11-16% out of the total viable count. In this microcosm experiment, initial concentration of TBT [1.0-1.4 microg/g (dry wt)] decreased to 0.6 microg/g (dry wt) during 150 days, whereas that in the control microcosm with autoclaved sediment did not change, indicating that Mekong River sediment contains high TBT-degrading activity by microorganisms. The occurrence of TBT-resistant bacteria and the bacterial community structures monitored by denaturing gradient gel electrophoresis were almost the same between test and control groups, indicating that the addition of TBT had little influence on microbial community structure. Mekong River sediment seems to have a stable microbial community against TBT pollution.
authors.affiliation: Center for Marine Environmental Studies (CMES), Ehime University, Matsuyama, Ehime, 790-8577, Japan.
authors.forename: Fujiyo
authors.initials: F
authors.lastname: Suehiro
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kobayashi
authors.forename: Lisa
authors.initials: L
authors.lastname: Nonaka
authors.forename: Bui Cach
authors.initials: BC
authors.lastname: Tuyen
authors.forename: Satoru
authors.initials: S
authors.lastname: Suzuki
mesh_terms: D001419:Bacteria / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism*; D001673:Biodegradation, Environmental; D015169:Colony Count, Microbial; D024881:Drug Resistance, Bacterial; D017753:Ecosystem; D004785:Environmental Pollutants / Q000032:analysis / Q000378:metabolism* / Q000494:pharmacology; D019015:Geologic Sediments / Q000737:chemistry / Q000382:microbiology*; D016133:Polymerase Chain Reaction; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D045483:Rivers / Q000382:microbiology*; D014220:Trialkyltin Compounds / Q000032:analysis / Q000378:metabolism* / Q000494:pharmacology; D014744:Vietnam
chemical_list: D004785:Environmental Pollutants; D012336:RNA, Ribosomal, 16S; D014220:Trialkyltin Compounds; C011559:tributyltin