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Martinez-Paramo S.,University of Algarve | Diogo P.,University of Algarve | Dinis M.T.,University of Algarve | Soares F.,Portuguese Institute of Sea and Atmosphere | And 2 more authors.
Cryobiology | Year: 2013

In the present work, taurine and hypotaurine were evaluated as potential additives to improve European sea bass (Dicentrarchus labrax) sperm quality after cryopreservation. For cryopreservation, three different extenders were used: control extender (NAM), supplemented with 1mM taurine or supplemented with 1mM hypotaurine, all of them containing 10% Me2SO as cryoprotectant. To evaluate sperm quality of fresh and thawed sperm, motility (CASA: computer assisted sperm analysis), viability (SYBR Green/propidium iodide), lipid peroxidation (malondialdehyde level), protein oxidation (carbonyl content), glutathione peroxidase, glutathione reductase and superoxide dismutase activities and DNA fragmentation (comet assay) were quantified. The result demonstrated that 1mM hypotaurine supplemented extender increased total motility (30.1±3.2%), and that 1mM taurine extender produced higher velocity (18.1±2.6μm/s) and linearity (46.0±4.8%) than the control extender (21.8±3.2%, 15.5±1.3μm/s, 41.8±2.4%, respectively). Cell viability, lipid peroxidation and protein oxidation were not statistically different between treatments. Similar results were obtained for glutathione peroxidase and superoxide dismutase activities. Only glutathione reductase showed differential activity before and after freezing, increasing its activity in thawed sperm. Regarding the comet assay results, taurine and hypotaurine significantly reduced DNA fragmentation (52.8±0.9% and 51.8±0.9%, respectively) in comparison to the control (55.7±0.8%). In conclusion, for European sea bass sperm cryopreservation, extenders supplemented with 1mM taurine and 1mM hypotaurine improved some parameters of sperm quality after thawing, resulting in better motility and lower DNA damage than the control, two very important factors related to fertilization success. © 2013 Elsevier Inc.


Santos-Echeandia J.,Portuguese Institute of Sea and Atmosphere | Santos-Echeandia J.,CSIC - Institute of Marine Research | Caetano M.,Portuguese Institute of Sea and Atmosphere | Laglera L.M.,University of the Balearic Islands | Vale C.,Portuguese Institute of Sea and Atmosphere
Chemosphere | Year: 2013

Dissolved copper levels, copper complexing capacities and conditional stability constants have been determined in the Tagus estuarine waters and one of the saltmarshes located in this estuary, the Rosario saltmarsh. Tagus estuarine waters show a constant and around 20nM copper concentration during the estuarine mixing. Most of this copper is organically complexed by a strong ligand (L1) with a concentration that varies between 19 and 55nM and a log K' between 14.14 and 15.75. In addition L1/Cu ratios are quite constants and close to 1 all through the estuary, indicating the same source. A second and weaker ligand (L2) was also detected in these waters in higher concentrations (36-368nM) but with a lower log K' that varies between 12.06 and 13.13. The present work has demonstrated that salt-marsh areas are important and continuous sources of copper complexing ligands to the Tagus estuary. Noticeable, tidal induced transport continuously feed these waters with copper and ligands, mainly with the stronger one. This continuous input, together with the high residence times of this system results in a quite constant concentration along the salinity gradient. This input represents 95% of the ligand present in the estuary. © 2012 Elsevier Ltd.


Santos-Echeandia J.,CSIC - Institute of Marine Research | Santos-Echeandia J.,Portuguese Institute of Sea and Atmosphere | Prego R.,CSIC - Institute of Marine Research | Cobelo-Garcia A.,CSIC - Institute of Marine Research | Caetano M.,Portuguese Institute of Sea and Atmosphere
Marine Chemistry | Year: 2012

The intra annual variation of the quantity and composition of the sinking particles in a ria coastal system (Vigo Ria, Galicia, NW Iberian Peninsula) has been studied. Levels of particulate metals (Al, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Ti, U, V and Zn) were determined both in the labile (1M HCl extraction) and in the total fraction. The levels and type of metals found in different seasons of the year depended upon oceanographic, physical, chemical and biological conditions but, in general, lithogenic type metals (Al, Fe, Ti, U and V) were higher during winter rainy campaigns when high quantities of SPM were recovered in the trap. However, the more biogenic metals (Cu, Pb and Zn) followed a scattered variation. Vertical fluxes values varied within the following intervals: 0.4-6.1gm -2d -1 for Al, 0.7-7.6μgm -2d -1 for Cd, 0.1-0.6mgm -2d -1 for Co, 0.8-6.4mgm -2d -1 for Cr, 1.2-10.9mgm -2d -1 for Cu, 0.3-2.7gm -2d -1 for Fe, 1.8-19.8mgm -2d -1 for Mn, 0.5-2.9mgm -2d -1 for Ni, 1.7-7.9mgm -2d -1 for Pb, 0.1-0.2gm -2d -1 for Ti, 0.1-0.6mgm -2d -1 for U, 0.6-7.2mgm -2d -1 for V and 0.8-39.8mgm -2d -1 for Zn. In special, the deposited labile fraction is subject to postdepositional diagenetic processes with subsequent benthic fluxes of dissolved Cr, Cu, Mn, Ni, Pb and Zn form of the metals to the water column. For Co and Cd, however, their enrichment in the sediments compared to the traps suggests their association with a more refractory fraction upon postdepositional remineralization. This work represents one of the first studies about labile trace metal concentrations and intra annual variation in the particulate matter recovered from a sediment trap in a ria system. © 2012 Elsevier B.V.


Raimundo J.,Portuguese Institute of Sea and Atmosphere | Pereira P.,Portuguese Institute of Sea and Atmosphere | Vale C.,Portuguese Institute of Sea and Atmosphere | Canario J.,Portuguese Institute of Sea and Atmosphere | And 2 more authors.
Chemosphere | Year: 2014

Mercury, methylmercury and selenium were determined in digestive gland, branchial hearts, mantle, kidney and gills of Sepia officinalis from two areas of the south Portuguese coast. To the best of our knowledge these are the first data on Hg, MeHg and Se in branchial hearts, kidney and gills of cuttlefish. Digestive gland, branchial hearts and kidney presented higher levels of Hg and Se than mantle and gills. Methylmercury was significantly higher in digestive gland, branchial hearts and mantle. The enhanced levels of Hg in digestive gland and branchial heart reinforce the elevated storage capacity of these two tissues. The percentage of MeHg varied from 6.1% in gills to 92% in mantle. Linear and positive MeHg-Hg relations were obtained for the five tissues, being the better relation and higher slope observed for mantle, followed by branchial hearts, digestive gland, kidney and gills. The Se:Hg molar ratios showed a surplus of Se in all tissues. Calculations based on the equimolarity of Se:Hg point that 95-99% of Se are not linked to Hg (Se free). The negligible quantity of Se associated with Hg suggests that the mechanism of MeHg demethylation was not triggered in none of the tissues, presumably because the threshold for MeHg toxicity was not achieved. © 2014 Elsevier Ltd.


Raimundo J.,Portuguese Institute of Sea and Atmosphere | Vale C.,Portuguese Institute of Sea and Atmosphere | Rosa R.,University of Lisbon
Ecotoxicology and Environmental Safety | Year: 2014

Jumbo (or Humboldt) squid, Dosidicus gigas, is a large jet-propelled top oceanic predator off the Eastern Pacific. The present study reports, for the first time, concentrations of V, Cr, Mn, Co, Ni, Cu, Zn, As, Se, Cd and Pb in gills, mantle and digestive gland of this powerful pelagic squid in the Gulf of California. Zinc and Cu were the most abundant elements. All elements, with the exception of As, were largely stored in digestive gland; particularly Cd that reached concentrations between 57 and 509 sgg-1. Significant relationships between tissues were found for Co (digestive gland-gills), As (gills-mantle) and Cd (digestive gland-mantle). Proportionality of Cd concentrations between mantle and digestive gland suggested that detoxification capacity by digestive gland was insufficient to avoid the transfer of this element to mantle and other tissues. Nonetheless, Cd concentrations in the mantle were always below the regulatory limit and, therefore lack of constraints for human consumption. On the basis of the fishery landings, one may estimate that up to 1t of Cd can be annually removed by jumbo squid fisheries. © 2014 Elsevier Inc.


Teixeira B.,Portuguese Institute of Sea and Atmosphere | Teixeira B.,University of Aveiro | Fidalgo L.,University of Aveiro | Mendes R.,Portuguese Institute of Sea and Atmosphere | And 5 more authors.
Innovative Food Science and Emerging Technologies | Year: 2014

High pressure processing (HPP) is a technology able to reduce microorganisms and to modify food functional properties. This study aims to investigate the effect of three pressure variables (pressure levels of 100-400 MPa, pressure holding time of 0-30 min, and pressurization rate of 8 and 14 MPa s- 1) in microbiological and physical analyses, and in myofibrillar proteins profiles in sea bass fillets. Pressurization rate induced changes in all parameters evaluated, although in a lesser extent than other variables. In general, the characteristics of fillets treated at 100 MPa were not different from non-treated samples. The magnitude of changes increased with pressure level (250-400 MPa) and holding time (0-30 min). In general, with the increase of pressure level and holding time, fillets become whitish, microbiological load and water holding capacity decreased, pH increased, and myofibrillar proteins with molecular weights below 30 kDa increased, whereas those with lower isolectric point values decreased. HPP can be a potential tool to process fillets due to the improvement in microbiological safety (about 2 log CFU g - 1 reduction in the treatment at 400 MPa-30 min), which might result in an extended shelf life. Industrial relevance High pressure processing is an interesting technology for food preservation due to its ability to reduce microorganisms and to modify food functional properties. This study brought new evidences about the effect of high pressure processing on sea bass fillets, namely in myofibrillar protein profiles (SDS-PAGE and IEF electrophoreses). Variables such as pressure holding time and pressurization rate, besides pressure level, are also important in the choice of high pressure processing conditions. The results also suggest that high pressure processing might delay the degradation of fish muscle. The advantages of products treated with high pressure processing can lead to new opportunities in the market, being important for the food industry. © 2014 Elsevier Ltd.


PubMed | Portuguese Institute of Sea and Atmosphere and University of Lisbon
Type: | Journal: Chemosphere | Year: 2014

Mercury, methylmercury and selenium were determined in digestive gland, branchial hearts, mantle, kidney and gills of Sepia officinalis from two areas of the south Portuguese coast. To the best of our knowledge these are the first data on Hg, MeHg and Se in branchial hearts, kidney and gills of cuttlefish. Digestive gland, branchial hearts and kidney presented higher levels of Hg and Se than mantle and gills. Methylmercury was significantly higher in digestive gland, branchial hearts and mantle. The enhanced levels of Hg in digestive gland and branchial heart reinforce the elevated storage capacity of these two tissues. The percentage of MeHg varied from 6.1% in gills to 92% in mantle. Linear and positive MeHg-Hg relations were obtained for the five tissues, being the better relation and higher slope observed for mantle, followed by branchial hearts, digestive gland, kidney and gills. The Se:Hg molar ratios showed a surplus of Se in all tissues. Calculations based on the equimolarity of Se:Hg point that 95-99% of Se are not linked to Hg (Se free). The negligible quantity of Se associated with Hg suggests that the mechanism of MeHg demethylation was not triggered in none of the tissues, presumably because the threshold for MeHg toxicity was not achieved.


Mil-Homens M.,National Laboratory of Energy and Geology | Blum J.,University of Michigan | Canario J.,Portuguese Institute of Sea and Atmosphere | Caetano M.,Portuguese Institute of Sea and Atmosphere | And 12 more authors.
Chemical Geology | Year: 2013

Three short marine sediment cores from the Cascais Submarine Canyon (CSC; cores 252-32 and 252-35) and the Estremadura Spur (core 252-16) on the central Portuguese Margin were analysed for Hg, Pb, Al, and Mn concentrations, and both Pb and Hg stable isotope compositions, in order to reconstruct trends in Hg and Pb sources and accumulation. Sediment ages were determined based on 210Pb measurements. The studied cores reveal increasing Hg and Pb concentration, independent of grain-size variations, since the middle of the 19th century towards the Present. Concomitantly, a decreasing trend of 206Pb/207Pb to less radiogenic values towards the surface was found, indicating increasing anthropogenic inputs. The lowest values of δ202Hg were generally observed in the older sediments characterized by low Hg and Pb concentrations, suggesting a low input of anthropogenic metals. Odd mass number (199Hg and 201Hg) Hg isotopes in sediment samples from core 252-16 were characterized by positive mass independent fractionation (MIF), while recent sediments from cores 252-32 and 252-35 did not reveal significant MIF, probably reflecting both the proximity to the source of anthropogenic Hg contamination (Tagus Estuary) and the importance of the CSC as a particle carrier. The multi-tracer approach, based on both stable Hg and Pb isotopic signatures, confirms anthropogenic Hg and Pb enrichment in recent marine sediments and also allows us to distinguish between areas dominated by detrital (e.g. CSC) versus hemipelagic (Estremadura Spur) sedimentation. © 2012 Elsevier B.V.


PubMed | Portuguese Institute of Sea and Atmosphere and CIIMAR – Interdisciplinary Center of Marine and Environmental
Type: Journal Article | Journal: Marine pollution bulletin | Year: 2014

Upper sediments (0-5 cm) were sampled in 94 sites of water bodies of the fifteen Portuguese estuaries characterized by distinct settings of climate, topography and lithology, and marked by diverse anthropogenic pressures. Confined areas recognized as highly anthropogenic impacted, as well as areas dominated by erosion or frequently dredged were not sampled. Grain size, organic carbon (Corg), Al and trace elements (As, Cd, Co, Cr, Cu, Hg, Ni, Pb and Zn) were determined. Normalisation of trace element concentrations to Al and Corg, correlations between elements and Principal Component Analysis (PCA) allowed identifying elemental associations and the relevance of grain-size, lithology and anthropogenic inputs on sediment chemical composition. Whereas grain-size is the dominant effect for the majority of the studied estuaries, the southern estuaries Mira, Arade and Guadiana are dominated by specific lithologies of their river basins, and anthropogenic effects are identified in Ave, Lea, Tagus and Sado. This study emphasizes how baseline values of trace elements in sediments may vary within and among estuarine systems.


Maulvault A.L.,Portuguese Institute of Sea and Atmosphere | Cardoso C.,Portuguese Institute of Sea and Atmosphere | Nunes M.L.,Portuguese Institute of Sea and Atmosphere | Marques A.,Portuguese Institute of Sea and Atmosphere
Food Control | Year: 2013

A risk-benefit assessment was performed in two marine resources of great importance in Southern Europe, i.e. black scabbard fish (Aphanopus carbo) and edible crab (Cancer pagurus), by determining the intake of Methyl-Hg, Cd, Se and EPA + DHA through the consumption of these species, as well as the associated probability of exceeding the tolerable weekly intakes (TWI; for Methyl-Hg and Cd) or dietary reference intakes (DRI; for Se and EPA + DHA). Average weekly intakes (AWI) were estimated by combination of the consumption frequencies in the Portuguese population and the concentration of each constituent. To estimate probabilities, two estimators were used: plug-in (PI) for higher probabilities and tail estimation (TE) based on the application of the extreme value theory to intakes distribution curves for lower probabilities. It was found that edible crab's white meat (meat from claws and legs) can be included on a well balanced diet, but black scabbard fish and edible crab's brown meat (mixture of gonads and hepatopancreas) should be consumed parsimoniously by adults and children. © 2013 Elsevier Ltd.

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