Natural peptides with antioxidant activity from Atlantic cod and Atlantic salmon residual material

Summary. Water-soluble peptides/proteins with molecular weight below 10 kDa were isolated from residual material of cod (liver, skin, and cod mix i.e. skin, frames, and viscera), and salmon (skin, and salmon mix i.e. skin, frames, and viscera) by cut-off filtration. Peptide motifs with reported bioactivity were identified in all samples by liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) (Orbitrap), bioinformatics, and database search. Peptides with potential type 2 diabetes, cardio system, immunomodulation, prolyl endopeptidase (PEP), and antioxidant activity were detected. The potential antioxidant activity in the samples was confirmed by two antioxidant assays, namely hydroxyl radical scavenging activity (HRSA), and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS) radical cation decolorization assay. In these assays the salmon samples were found to possess higher antioxidant activity than the cod samples. All samples except the cod skin were found to have higher antioxidant activity than alanine-histidine (AH), a dipeptide with known antioxidant activity. Industrial relevance. Residual material from fisheries and aquaculture makes up large quantities of material. Although previously regarded as waste this material has valuable components that are of interest for the biotech industry. The fractionation process utilized in this work offers the possibility for simple isolation of interesting peptides with antioxidant activity. This method should be of interest for the food industry and biotech industry for product development

Modeling of Environmental Fate and Effects of Oil Leakages from Abandoned Subsea Wells Using an Environmental Impact Factor Tool

Potential environmental consequences of oil leakages (i.e., continuous uncontrolled releases at low flow rate over a long period of time) need to be taken into consideration in the ongoing development of plug and abandonment (P&A) activities on the Norwegian continental shelf. Regulations of P&A wells employ a “zero leakage” target; however, environmental risk monitoring strategies for permanent abandonment are not yet in place. Predicting and estimating the consequences of adverse environmental impacts through a modeling approach can play a key role in evaluating and monitoring environmental risk. In this paper, we present a modeling study of the fate and effects of an oil leakage from abandoned wells using a theoretical scenario on the Norwegian continental shelf. Environmental impact factors (EIFs) derived from the Dose related Risk and Effect Assessment Model (DREAM), previously designed to characterize the effects of produced water discharges, were used to assess impacts of leakages from abandoned wells. Exposure assessments for the EIFs were modified to include specific hydrocarbon contributions derived from different sized oil droplets from the leakages. Because DREAM is not generally used for chronic low-rate oil releases, an update of the database with chronic predicted no-effect concentrations, as input data for effects modeling, was conducted. In general, EIFs became stable after simulations of 30 d. The area from the release site and up to a few hundred meters southward had the most locations of high impact. Chronic exposure and effects on organisms potentially occurred as a steady-state effect over a long period. Risks, at which more than 95% of species will be negatively affected, appeared surrounding the release site, indicating a need for mitigation measures. These results show that the EIF tool can be used for risk management and P&A regulation by identifying potentially harmful leakages.publishedVersio

Relationships between Isomeric Metabolism and Regioselective Toxicity of Hydroxychrysenes in Embryos of Japanese Medaka (Oryzias latipes)

Oxygenated polycyclic aromatic hydrocarbons (oxy-PAHs) are ubiquitous contaminants that can be formed through oxidation of parent PAHs. Our previous studies found 2-hydroxychrysene (2-OHCHR) to be significantly more toxic to Japanese medaka embryos than 6-hydroxychrysene (6-OHCHR), an example of regioselective toxicity. We have also previously identified a sensitive developmental window to 2-OHCHR toxicity that closely coincided with liver development, leading us to hypothesize that differences in metabolism may play a role in the regioselective toxicity. To test this hypothesis, Japanese medaka embryos were treated with each isomer for 24 h during liver development (52–76 hpf). Although 6-OHCHR was absorbed 97.2 ± 0.18% faster than 2-OHCHR, it was eliminated 57.7 ± 0.36% faster as a glucuronide conjugate. Pretreatment with cytochrome P450 inhibitor, ketoconazole, reduced anemia by 96.8 ± 3.19% and mortality by 95.2 ± 4.76% in 2-OHCHR treatments. Formation of chrysene-1,2-diol (1,2-CAT) was also reduced by 64.4 ± 2.14% by ketoconazole pretreatment. While pretreatment with UDP-glucuronosyltransferase inhibitor, nilotinib, reduced glucuronidation of 2-OHCHR by 52.4 ± 2.55% and of 6-OHCHR by 63.7 ± 3.19%, it did not alter toxicity for either compound. These results indicate that CYP-mediated activation, potentially to 1,2-CAT, may explain the isomeric differences in developmental toxicity of 2-OHCHR.publishedVersio

Natural peptides with antioxidant activity from Atlantic cod and Atlantic salmon residual material

Summary. Water-soluble peptides/proteins with molecular weight below 10 kDa were isolated from residual material of cod (liver, skin, and cod mix i.e. skin, frames, and viscera), and salmon (skin, and salmon mix i.e. skin, frames, and viscera) by cut-off filtration. Peptide motifs with reported bioactivity were identified in all samples by liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) (Orbitrap), bioinformatics, and database search. Peptides with potential type 2 diabetes, cardio system, immunomodulation, prolyl endopeptidase (PEP), and antioxidant activity were detected. The potential antioxidant activity in the samples was confirmed by two antioxidant assays, namely hydroxyl radical scavenging activity (HRSA), and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS) radical cation decolorization assay. In these assays the salmon samples were found to possess higher antioxidant activity than the cod samples. All samples except the cod skin were found to have higher antioxidant activity than alanine-histidine (AH), a dipeptide with known antioxidant activity. Industrial relevance. Residual material from fisheries and aquaculture makes up large quantities of material. Although previously regarded as waste this material has valuable components that are of interest for the biotech industry. The fractionation process utilized in this work offers the possibility for simple isolation of interesting peptides with antioxidant activity. This method should be of interest for the food industry and biotech industry for product development

The Water Column Monitoring Programme 2013: Determining the biological effects of two offshore platforms on local fish populations

-The biological effects of two offshore oil platforms on local fish populations were assessed as part of the Water Column Monitoring (WCM) programme for 2013. Wild fish were caught with baited rod and line from within the 500 m safety zone of the Veslefrikk and Oseberg Sør platforms during the summer of 2013. Ling, tusk and saithe were caught and sampled from the Veslefrikk platform, whilst haddock, whiting and saithe were caught from the Oseberg Sør platform. Reference fish were caught on a separate research cruise by trawling from a region of the North Sea less impacted by oil and gas activities (around Egersund bank). Reference tusk were not obtained by trawl but caught by local fishermen from a coastal fjord using long line. Contaminant body burden and a suite of biological effects endpoints were measured in all fish groups and included DNA adducts, DNA strand breaks by comet assay, acetylcholine esterase inhibition (AChE), ethoxyresorufin 0-deethylase levels (EROD), lysosomal membrane stability (LMS), histology, PAH metabolites, and PAH body burden. The biomarker data were integrated using the integrated biological response index (IBR/n). Biological responses were observed in fish species from both platforms compared to their respective reference groups with highest responses observed in tusk from the Veslefrikk platform.Norsk Oil and Gas, represented by Statoil AS

Water Column Monitoring 2014: Determining the biological effects of an offshore platform on local fish populations

The biological effects of an offshore oil platform on local fish populations were assessed as part of the Water Column Monitoring (WCM) programme for 2014. The Njord A platform was chosen as the study location, which was not in operation and had no current discharge of produced water. Demersal fish species were targeted since they were believed to be less likely to migrate away from the platform than pelagic fish. By targeting organisms deeper in the water column and selecting a platform currently not in operation, the impact of drill cuttings and other sediment sources including leakages from well deposits were the main sources of contamination. Wild fish including ling (Molva molva), tusk (Brosme brosme), redfish (Sebastes sp.) and saithe (Pollachius virens) were caught with baited rod and line from within the 500 m safety zone of the Njord A platform during the summer of 2014. Reference fish were caught on a separate research cruise by trawling from a region of the Norwegian Sea less impacted by oil and gas activities. Limited numbers of reference ling were obtained and the reference data for ling collected from the North Sea as part of the WCM2013 programme were used for comparison of the biomarker responses. Contaminant body burden and a suite of biological effects endpoints were measured in all fish groups and included DNA adducts, DNA strand breaks by comet assay, acetylcholine esterase (AChE) inhibition, ethoxyresorufin 0-deethylase (EROD), vitellogenin (VTG), lysosomal membrane stability (LMS), liver and gill histopathology, PAH metabolites, and PAH body burden. The biomarker data were integrated using the integrated biological response index (IBR/n). Despite low and/or undetected concentrations of PAH and PAH metabolites in fish fillet and bile respectively significant responses in AChE, comet and DNA adducts were found. The biomarker responses indicated exposure to both neurotoxic and genotoxic chemicals in fish inhabiting the lower water column with influence from sediment sources around the Njord A platform. Integration of the biomarker responses (IBR/n) found that all four fish species that were caught from around the platform had markedly higher IBR/n values than their respective reference population. The study shows the advantage of using a suite of biomarkers for assessing the biological effects of low concentrations of complex mixtures with biological effects observed despite low concentrations of PAH measured.Norwegian Oil and Gas, represented by Statoil AS

The Water Column Monitoring Programme 2013: Determining the biological effects of two offshore platforms on local fish populations

The biological effects of two offshore oil platforms on local fish populations were assessed as part of the Water Column Monitoring (WCM) programme for 2013. Wild fish were caught with baited rod and line from within the 500 m safety zone of the Veslefrikk and Oseberg Sør platforms during the summer of 2013. Ling, tusk and saithe were caught and sampled from the Veslefrikk platform, whilst haddock, whiting and saithe were caught from the Oseberg Sør platform. Reference fish were caught on a separate research cruise by trawling from a region of the North Sea less impacted by oil and gas activities (around Egersund bank). Reference tusk were not obtained by trawl but caught by local fishermen from a coastal fjord using long line. Contaminant body burden and a suite of biological effects endpoints were measured in all fish groups and included DNA adducts, DNA strand breaks by comet assay, acetylcholine esterase inhibition (AChE), ethoxyresorufin 0-deethylase levels (EROD), lysosomal membrane stability (LMS), histology, PAH metabolites, and PAH body burden. The biomarker data were integrated using the integrated biological response index (IBR/n). Biological responses were observed in fish species from both platforms compared to their respective reference groups with highest responses observed in tusk from the Veslefrikk platform

Synthesis of trans-dihydronaphthalene-diol and evaluation of their use as standards for PAH metabolite analysis in fish bile by GC-MS

Phenols and trans-1,2-dihydro-1,2-diols are metabolites commonly formed in vivo in fish upon exposure to polycyclic aromatic hydrocarbons (PAHs). These metabolites are excreted via the bile and gas chromatography-mass spectrometry (GC-MS) analysis of bile is becoming more frequently used for evaluating PAH exposure levels in fish. Current protocols focus on the detection and quantification of phenols formed during in vivo oxidation of PAHs, leaving out analyses and quantification of other oxidation products such as trans-1,2-dihydro-1,2-diols, potentially underestimating exposure levels. Herein, four trans-1,2-dihydro-1,2-diols, namely trans-1,2-dihydronaphthalene-1,2-diol, trans-6-methyl-1,2-dihydronaphthalene-1,2-diol, trans-5,7-dimethyl-1,2-dihydronaphthalene-1,2-diol, and trans-4,6,7-trimethyl-1,2-dihydronaphthalene-1,2-diol, were successfully prepared and used as standards in the GC-MS analysis, aiming to further develop this qualitative and quantitative analytical method for the determination of PAH exposures. This study shows that the currently used GC-MS analysis, including sample workup, is not suitable for determining the quantity of the corresponding diols derived from naphthalene and methylated naphthalenes. Alternative approaches are needed to provide a correct estimate of PAH exposure levels.publishedVersio