The Experts below are selected from a list of 2148 Experts worldwide ranked by ideXlab platform
Martin Schlabach - One of the best experts on this subject based on the ideXlab platform.
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persistent Organohalogen contaminant burdens in antarctic krill euphausia superba from the eastern antarctic sector a baseline study
Science of The Total Environment, 2008Co-Authors: S Bengtson M Nash, Anita Poulsen, So Kawaguchi, Walter Vetter, Martin SchlabachAbstract:A baseline for persistent Organohalogen Compound (POC) accumulation in the Antarctic keystone species, Antarctic krill (Euphausia superba) has been established for a 50° longitudinal range of the eastern Antarctic sector. Samples of adult krill, caught from 12 sites distributed between 30° and 80°E (60–70°S), were analysed for N100 Organohalogen Compounds including chlorinated pesticides, polychlorinated biphenyls (PCBs), polybrominated organic Compounds and polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs). Organochlorine pesticides dominated measured krill contaminant burdens with hexachlorobenzene (HCB) as the single most abundant Compound quantified. Krill HCB concentrations were comparable to those detected at this trophic level in both the Arctic and temperatenorthwestAtlantic, lendingsupport for thehypothesis thatHCB will approachglobal equilibriumat a faster rate than other POCs. Para, para′-dichlorodiphenylethene (p,p′-DDE)was detected at notable concentrations. Measurements of DDT and its degradation products provide an important baseline for monitoring the temporal and geographical influence of renewed, DDT usage for malaria-control in affected southern hemisphere countries. In contrast to the Arctic, PCBs did not feature prominently in contaminant burdens of Antarctic krill. Themajor commercial polybrominated diphenyl ether (PBDE) congeners -99 and -47 were quantified at lowbackground levelswith clear concentration spikes observed at around 70°E , in the vicinity of modern, active research stations. The likelihood that local anthropogenic activities are supplementing low PBDE levels, delivered otherwise primarily via long range environmental transport, is discussed. The suspected naturally occurring brominated organic Compound, 2,4,6-tribromoanisole (TBA), was a ubiquitous contaminant in all samples whereas the only PCDD/Fs quantifiable were trace levels of octachlorodibenzo-p-dioxin (OCDD) and 1,2,3,4,7,8/1,2,3,4,7,9-hexachlorodibenzofuran (HxCDF). With the aims of; i) Generating a robust and broadly applicable POC auditing platform for the scarcely studied eastern Antarctic sector; ii) Determining the Compounds accumulating in Antarctic krill for further toxicity evaluation studies and iii) Establishing a baseline for Antarctic predator exposure to POCs, this study represents one of the most comprehensive reports of POC contamination of the Antarctic food web to date.
S Bengtson M Nash - One of the best experts on this subject based on the ideXlab platform.
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persistent Organohalogen contaminant burdens in antarctic krill euphausia superba from the eastern antarctic sector a baseline study
Science of The Total Environment, 2008Co-Authors: S Bengtson M Nash, Anita Poulsen, So Kawaguchi, Walter Vetter, Martin SchlabachAbstract:A baseline for persistent Organohalogen Compound (POC) accumulation in the Antarctic keystone species, Antarctic krill (Euphausia superba) has been established for a 50° longitudinal range of the eastern Antarctic sector. Samples of adult krill, caught from 12 sites distributed between 30° and 80°E (60–70°S), were analysed for N100 Organohalogen Compounds including chlorinated pesticides, polychlorinated biphenyls (PCBs), polybrominated organic Compounds and polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs). Organochlorine pesticides dominated measured krill contaminant burdens with hexachlorobenzene (HCB) as the single most abundant Compound quantified. Krill HCB concentrations were comparable to those detected at this trophic level in both the Arctic and temperatenorthwestAtlantic, lendingsupport for thehypothesis thatHCB will approachglobal equilibriumat a faster rate than other POCs. Para, para′-dichlorodiphenylethene (p,p′-DDE)was detected at notable concentrations. Measurements of DDT and its degradation products provide an important baseline for monitoring the temporal and geographical influence of renewed, DDT usage for malaria-control in affected southern hemisphere countries. In contrast to the Arctic, PCBs did not feature prominently in contaminant burdens of Antarctic krill. Themajor commercial polybrominated diphenyl ether (PBDE) congeners -99 and -47 were quantified at lowbackground levelswith clear concentration spikes observed at around 70°E , in the vicinity of modern, active research stations. The likelihood that local anthropogenic activities are supplementing low PBDE levels, delivered otherwise primarily via long range environmental transport, is discussed. The suspected naturally occurring brominated organic Compound, 2,4,6-tribromoanisole (TBA), was a ubiquitous contaminant in all samples whereas the only PCDD/Fs quantifiable were trace levels of octachlorodibenzo-p-dioxin (OCDD) and 1,2,3,4,7,8/1,2,3,4,7,9-hexachlorodibenzofuran (HxCDF). With the aims of; i) Generating a robust and broadly applicable POC auditing platform for the scarcely studied eastern Antarctic sector; ii) Determining the Compounds accumulating in Antarctic krill for further toxicity evaluation studies and iii) Establishing a baseline for Antarctic predator exposure to POCs, this study represents one of the most comprehensive reports of POC contamination of the Antarctic food web to date.
Ying Huang - One of the best experts on this subject based on the ideXlab platform.
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detection distribution and Organohalogen Compound discovery implications of the reduced flavin adenine dinucleotide dependent halogenase gene in major filamentous actinomycete taxonomic groups
Applied and Environmental Microbiology, 2009Co-Authors: P Gao, Ying HuangAbstract:Halogenases have been shown to play a significant role in biosynthesis and introducing the bioactivity of many halogenated secondary metabolites. In this study, 54 reduced flavin adenine dinucleotide (FADH 2 )-dependent halogenase gene-positive strains were identified after the PCR screening of a large collection of 228 reference strains encompassing all major families and genera of filamentous actinomycetes. The wide distribution of this gene was observed to extend to some rare lineages with higher occurrences and large sequence diversity. Subsequent phylogenetic analyses revealed that strains containing highly homologous halogenases tended to produce halometabolites with similar structures, and halogenase genes are likely to propagate by horizontal gene transfer as well as vertical inheritance within actinomycetes. Higher percentages of halogenase gene-positive strains than those of halogenase gene-negative ones contained polyketide synthase genes and/or nonribosomal peptide synthetase genes or displayed antimicrobial activities in the tests applied, indicating their genetic and physiological potentials for producing secondary metabolites. The robustness of this halogenase gene screening strategy for the discovery of particular biosynthetic gene clusters in rare actinomycetes besides streptomycetes was further supported by genome-walking analysis. The described distribution and phylogenetic implications of the FADH 2 -dependent halogenase gene present a guide for strain selection in the search for novel Organohalogen Compounds from actinomycetes.
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detection distribution and Organohalogen Compound discovery implications of the reduced flavin adenine dinucleotide dependent
2009Co-Authors: P Gao, Ying HuangAbstract:Specialized Research Fund ; National Hi-Tech Research and Development Program of China [2007AA09Z420]
Anita Poulsen - One of the best experts on this subject based on the ideXlab platform.
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persistent Organohalogen contaminant burdens in antarctic krill euphausia superba from the eastern antarctic sector a baseline study
Science of The Total Environment, 2008Co-Authors: S Bengtson M Nash, Anita Poulsen, So Kawaguchi, Walter Vetter, Martin SchlabachAbstract:A baseline for persistent Organohalogen Compound (POC) accumulation in the Antarctic keystone species, Antarctic krill (Euphausia superba) has been established for a 50° longitudinal range of the eastern Antarctic sector. Samples of adult krill, caught from 12 sites distributed between 30° and 80°E (60–70°S), were analysed for N100 Organohalogen Compounds including chlorinated pesticides, polychlorinated biphenyls (PCBs), polybrominated organic Compounds and polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs). Organochlorine pesticides dominated measured krill contaminant burdens with hexachlorobenzene (HCB) as the single most abundant Compound quantified. Krill HCB concentrations were comparable to those detected at this trophic level in both the Arctic and temperatenorthwestAtlantic, lendingsupport for thehypothesis thatHCB will approachglobal equilibriumat a faster rate than other POCs. Para, para′-dichlorodiphenylethene (p,p′-DDE)was detected at notable concentrations. Measurements of DDT and its degradation products provide an important baseline for monitoring the temporal and geographical influence of renewed, DDT usage for malaria-control in affected southern hemisphere countries. In contrast to the Arctic, PCBs did not feature prominently in contaminant burdens of Antarctic krill. Themajor commercial polybrominated diphenyl ether (PBDE) congeners -99 and -47 were quantified at lowbackground levelswith clear concentration spikes observed at around 70°E , in the vicinity of modern, active research stations. The likelihood that local anthropogenic activities are supplementing low PBDE levels, delivered otherwise primarily via long range environmental transport, is discussed. The suspected naturally occurring brominated organic Compound, 2,4,6-tribromoanisole (TBA), was a ubiquitous contaminant in all samples whereas the only PCDD/Fs quantifiable were trace levels of octachlorodibenzo-p-dioxin (OCDD) and 1,2,3,4,7,8/1,2,3,4,7,9-hexachlorodibenzofuran (HxCDF). With the aims of; i) Generating a robust and broadly applicable POC auditing platform for the scarcely studied eastern Antarctic sector; ii) Determining the Compounds accumulating in Antarctic krill for further toxicity evaluation studies and iii) Establishing a baseline for Antarctic predator exposure to POCs, this study represents one of the most comprehensive reports of POC contamination of the Antarctic food web to date.
So Kawaguchi - One of the best experts on this subject based on the ideXlab platform.
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persistent Organohalogen contaminant burdens in antarctic krill euphausia superba from the eastern antarctic sector a baseline study
Science of The Total Environment, 2008Co-Authors: S Bengtson M Nash, Anita Poulsen, So Kawaguchi, Walter Vetter, Martin SchlabachAbstract:A baseline for persistent Organohalogen Compound (POC) accumulation in the Antarctic keystone species, Antarctic krill (Euphausia superba) has been established for a 50° longitudinal range of the eastern Antarctic sector. Samples of adult krill, caught from 12 sites distributed between 30° and 80°E (60–70°S), were analysed for N100 Organohalogen Compounds including chlorinated pesticides, polychlorinated biphenyls (PCBs), polybrominated organic Compounds and polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs). Organochlorine pesticides dominated measured krill contaminant burdens with hexachlorobenzene (HCB) as the single most abundant Compound quantified. Krill HCB concentrations were comparable to those detected at this trophic level in both the Arctic and temperatenorthwestAtlantic, lendingsupport for thehypothesis thatHCB will approachglobal equilibriumat a faster rate than other POCs. Para, para′-dichlorodiphenylethene (p,p′-DDE)was detected at notable concentrations. Measurements of DDT and its degradation products provide an important baseline for monitoring the temporal and geographical influence of renewed, DDT usage for malaria-control in affected southern hemisphere countries. In contrast to the Arctic, PCBs did not feature prominently in contaminant burdens of Antarctic krill. Themajor commercial polybrominated diphenyl ether (PBDE) congeners -99 and -47 were quantified at lowbackground levelswith clear concentration spikes observed at around 70°E , in the vicinity of modern, active research stations. The likelihood that local anthropogenic activities are supplementing low PBDE levels, delivered otherwise primarily via long range environmental transport, is discussed. The suspected naturally occurring brominated organic Compound, 2,4,6-tribromoanisole (TBA), was a ubiquitous contaminant in all samples whereas the only PCDD/Fs quantifiable were trace levels of octachlorodibenzo-p-dioxin (OCDD) and 1,2,3,4,7,8/1,2,3,4,7,9-hexachlorodibenzofuran (HxCDF). With the aims of; i) Generating a robust and broadly applicable POC auditing platform for the scarcely studied eastern Antarctic sector; ii) Determining the Compounds accumulating in Antarctic krill for further toxicity evaluation studies and iii) Establishing a baseline for Antarctic predator exposure to POCs, this study represents one of the most comprehensive reports of POC contamination of the Antarctic food web to date.