Papers by Maria Leonor Nunes
Frontiers in Nutrition
AimThus, the aim of this study was to answer three scientific questions: (1) Are the protein cont... more AimThus, the aim of this study was to answer three scientific questions: (1) Are the protein content and amino acid profile of dried salted cod influenced by species (Gadus morhua and Gadus macrocephalus)? (2) Are the protein content and amino acid profile of dried salted cod influenced by the geographical area of capture (Iceland and Norway)? and (3) Does the amino acid profile have the potential to be used as a discriminator of species and geographical areas of capture?MethodsA total of 45 dried salted cods (2–3 kg of dry weight; n = 15 samples/origin) were used in this study. The Atlantic cod was fished in the Atlantic northeast (FAO 27 area) within the Exclusive Economic zones (EEZ) of Norway (n = 15) and Iceland (n = 15), while the Pacific cod was caught in the Pacific northeast (FAO 67 area) within the Alaska EEZ (n = 15). Total protein content was determined by the Kjeldahl method, in accordance with the AOAC procedures. The amino acid profile was analyzed by HPLC with fluore...
info:eu-repo/semantics/publishedVersio
Marine pollution bulletin, Jan 15, 2015
The recurrent emergence of infections outbreaks associated with shellfish consumption is an impor... more The recurrent emergence of infections outbreaks associated with shellfish consumption is an important health problem, which results in substantial economic losses to the seafood industry. Even after depuration, shellfish is still involved in outbreaks caused by pathogenic bacteria, which increases the demand for new efficient strategies to control the shellfish infection transmission. Phage therapy during the shellfish depuration is a promising approach, but its success depends on a detailed understanding of the dynamics of bacterial communities in the harvesting waters. This study intends to evaluate the seasonal dynamics of the overall bacterial communities, disease-causing bacterial populations and bacterial sanitary quality indicators in two authorized harvesting-zones at Ria de Aveiro. During the hot season, the total bacterial community presented high complexity and new prevalent populations of the main shellfish pathogenic bacteria emerged. These results indicate that the spr...
N.M. Bandarra, D. Duarte, R. Pinto, C. Sampayo, M. Ramos, I. Batista, M.L. Nunes, A.P. Batista, A... more N.M. Bandarra, D. Duarte, R. Pinto, C. Sampayo, M. Ramos, I. Batista, M.L. Nunes, A.P. Batista, A. Raymundo, L. Gouveia, B.S. Lima (1) INRB/L-IPIMAR, Av. Brasília 1449-006 Lisboa, Portugal; (2), IMED.UL, Faculdade de Farmácia Universidade de Lisboa, Av das Forcas Armadas 1600 Lisboa, Portugal. (3) Núcleo de Investigação em Engenharia Alimentar e Biotecnologia, Instituto Piaget ISEIT de Almada, Quinta da Arreinela de Cima, 2800-305 Almada, Portugal; (4) Instituto Nacional de Engenharia e Tecnologia Industrial INETI-DER Unidade Biomassa, Estrada do Paço do Lumiar, 1649-038 Lisboa, Portugal
Food and Chemical Toxicology, 2020
Reducing consumption of salt, specifically sodium, is one of the most effective ways to improve p... more Reducing consumption of salt, specifically sodium, is one of the most effective ways to improve public health. A novel formulation for producing salmon pâté with reduced sodium content was investigated. Salmon pâtés with three different sodium concentrations were evaluated using microbiological, sensory and chemical analyses. Saltwell®, a natural salt containing a mixture of sodium chloride and potassium chloride, was used for partial substitution of sodium chloride (table salt) alone in the formulation. Replacing 80 % of the sodium chloride with Saltwell®, resulted in a 22 % reduction in sodium, without affecting microbial activity or shelf-life. A trained sensory panel observed minor differences in three of the twelve sensory attributes that were evaluated (coherent texture, saltiness, canned fish flavor). However, these differences were weakly significant, and it is unlikely that consumers would identify these characteristics as unpalatable: evaluators in the trained sensory panel are much more sensitive to subtle differences in the products. Response to Reviewers: See detailed response to reviewers.
Carbohydrate Polymers, 2003
A compilation is presented of seven contributions from fishermen or representatives from National... more A compilation is presented of seven contributions from fishermen or representatives from National Fishermen's Organisations about Good Manufacturing Practice (GMP) on board of vessels in Portugal, Norway, the Netherlands, Italy, Spain, France and United Kingdom
British Journal of Nutrition, 2007
The effects of graded levels (0 %, 0·5 %, 0·75 and 1 %) of dietary conjugated linoleic acid (CLA)... more The effects of graded levels (0 %, 0·5 %, 0·75 and 1 %) of dietary conjugated linoleic acid (CLA) were assessed on 97 g rainbow trout. Fish were fed to satiation twice a day for 12 weeks. At the end of the experiment, all groups of fish weighed more than 250 g and no significant differences were detected in growth performance, feed conversion, nutrient or energy utilisation or body composition between treatments. A decrease in liver lipid content resulted from including CLA and was accompanied by a reduction in malic enzyme activity. The muscle saturated acid and PUFA content did not vary between dietary treatments, despite the increasing concentration of stearic acid and CLA. In the liver, however, both fractions increased significantly with dietary CLA. Moreover, the MUFA decreased significantly in both muscle and liver. CLA was incorporated into tissue lipids, with levels in flesh (2·1–4·2 %) being 2-fold higher than in liver (0·8–1·9 %). In muscle, the percentage of cis-9, trans...
Applied Biochemistry and Biotechnology, 2015
Fermentative protein hydrolysates (FPH) were prepared with a proteolytic bacterium, Bacillus stra... more Fermentative protein hydrolysates (FPH) were prepared with a proteolytic bacterium, Bacillus strain exhibiting high proteolytic activity. Three FPH with 1, 2, and 4 % of cod protein hydrolysate (CPH) and 0.5 % of yeast extract in the culture were prepared. The yields achieved varied between 30 and 58 % based on protein content. A general decrease of leucine, isoleucine, valine, alanine, arginine, threonine, proline, and glutamic acid was observed. All FPHs showed higher reducing power and DPPH radical scavenging activity than CPH, but similar ABTS radical scavenging activity. However, FPHs exhibited lower Cu+2-chelating activity than CPH. The ACE inhibitory activity of FPHs was not improved relatively to that recorded in CPH. The fermentative process seems to have potential to obtaining hydrolysates with improved biological activities or even to produce protein hydrolysates from native fish proteins.
Changes in content of selenium and taurine, and the alteration of fatty acid profile have been st... more Changes in content of selenium and taurine, and the alteration of fatty acid profile have been studied in African catfish fillets subjected to a commercial cold- or hot smoking process. Selenium content and the fatty acid profile did not change significantly during neither of the smoking procedures. Losses of taurine were 32 and 19 % during cold-smoking and hot-smoking, respectively. Significantly more taurine was lost during cold-smoking (P < 0.05), probably due to the prolonged brining and smoking procedure. The results support conclusions from other studies, showing that low molecular water soluble components are more susceptible to losses during processing of seafood.
The effect of spermatogenesis and oogenesis on protein, lipid, glycogen, cholesterol and energy c... more The effect of spermatogenesis and oogenesis on protein, lipid, glycogen, cholesterol and energy contents, total amino acid and fatty acid profiles of Eledone cirrhosa and Eledone moschata tissues (gonad, digestive gland and muscle) was investigated. A significant (p&amp;amp;amp;amp;lt;0.05) increase in the amino acids and protein content of the gonad throughout sexual maturation (namely in oogenesis) was observed, but the allocation of these nitrogen compounds from the digestive gland and muscle was not evident. The major essential amino acids (EAA) in the three tissues were leucine, lysine and arginine. The major nonessential amino acids (NEAA) were glutamic acid, aspartic acid and alanine. A significant increase in lipid and fatty acid contents of gonad and digestive gland was observed. There was also little evidence of accumulated lipid storage reserves being used for egg production. It seems that for egg production Eledone species use energy directly from food, rather than from stored products. Most of saturated fatty acid (SFA) content of the three tissues was presented as 16:0 and 18:0, monounsaturated fatty acid (MUFA) content as 18:1 and 20:1 and polyunsaturated fatty acid (PUFA) content as 20:4n-6, 20:5n-3 and 22:6n-3. Cholesterol and glycogen contents significantly increased in gonad and digestive gland throughout maturation while the muscle revealed no obvious pattern. If Eledone&amp;amp;amp;amp;#39;s component sterols are of a dietary origin, a considerable variation in the cholesterol content between species might be expected on the basis of the sterol composition of their prey. Although spermatogenesis and oogenesis had a significant effect (p&amp;amp;amp;amp;lt;0.05) in gonad and digestive gland energy content, the biochemical composition of digestive gland and muscle may not be primarily influenced by sexual maturation, but rather by other biotic factors such as feeding activity, food availability, spawning and brooding.
Food and Chemical Toxicology, Jan 31, 2009
The brown crab Cancer pagurus is highly appreciated in Southern European countries and edible tis... more The brown crab Cancer pagurus is highly appreciated in Southern European countries and edible tissues are consumed separately or as mixtures. This species is mostly harvested along the Scottish Coast and English Channel and has different market prices depending on the catching area and sex. The aim of this study was to quantify and characterize the contents of S, As, Br, Sr, Cd, Hg and Pb in muscle, hepatopancreas, gonads and gills of female and male crabs from both catching areas. Additionally, the accumulation patterns ...
Ciênc. Tecnol. …, 2008
A carne congelada de caranguejo uçá (Ucides cordatus) é encontrada com facilidade nas lojas espec... more A carne congelada de caranguejo uçá (Ucides cordatus) é encontrada com facilidade nas lojas especializadas em pescados ou supermercados em Fortaleza (Nordeste, Brasil). Neste trabalho, uma inovação no processamento é proposta através da utilização da máquina ...
Scientia …, 2004
The present study aimed to identify and quantify the dimethyl acetal (DMA) levels in the muscle o... more The present study aimed to identify and quantify the dimethyl acetal (DMA) levels in the muscle of Octopus vulgaris Cuvier, 1797, and to investigate the possible influence of octopus feeding ecology on their spatial and seasonal variations. The research was performed over one year in three areas of the Portuguese coast: Viana do Castelo, Cascais and Tavira. Significantly higher values of DMA were detected in Tavira (p<0.05), an area where the importance of bivalves in the octopus' diet was higher. The biochemical analyses performed in several prey items, belonging to five major taxonomic groups identified in octopus stomachs, revealed significant differences in DMA levels (p<0.05). The highest values were obtained in bivalves (1.15 mg 100 g-1 dry weight), followed by gastropods (0.74 mg 100g-1 dw), cephalopods (0.67 mg 100 g-1 dw), crustaceans (0.23 mg 100 g-1 dw) and osteichthyes (0.10 mg 100 g-1 dw). Therefore, based on these findings it can be speculated that the higher DMA levels in O. vulgaris obtained in Tavira throughout the year were evidence of its feeding ecology. Since DMAs are derived from ether glycerophospholipids, including plasmalogens (PLMs), the importance and role of this phospholipid class is discussed.
Coastal upwelling ecosystems provide the bulk of the world's fishery yields, but the biochemical ... more Coastal upwelling ecosystems provide the bulk of the world's fishery yields, but the biochemical ecology of the species that make up these fisheries has, surprisingly, been ignored. Biochemical indicators can provide a mechanistic, ecosystem-based link between population and ecosystem dynamics. Here we investigated long-term, inter-annual changes in the proximate composition and energetic condition of European sardine Sardina pilchardus and its relationship with oceanographic conditions in the Western Iberian Upwelling Ecosystem. Energy density (ED) ranged between 4.0 and 14.2 kJ g-1 , and the seasonal cycle largely determined temporal variability, explaining > 80% of the observed variation. ED variations were also closely linked with water (total R 2 = 99.0% in whole body; total R 2 = 95.0% in muscle) and lipid dynamics (total R 2 = 99.6% in whole body; total R 2 = 92.5% in muscle). After adjusting for seasonality (rED) and restricting the temporal analysis to the end of the feeding period (August to October), spring/early-summer oceanographic conditions explained 67% of the late-summer energetic peak. Interestingly, the sardine rED peak in year (t) explained > 54.4% of the variation in the annual catches of year (t + 1), indicating that adult energetic condition during spawning is partially translated into the fishery through parental effects in recruitment strength. Our results support earlier findings indicating that sardine population dynamics seem to be controlled by bottom-up effects, but the linkages between population dynamics and patterns in environmental variability via physiological condition seem to have previously been overlooked. We also provide empirical evidence that biochemical assessments during critical periods of the life-cycle of fish are essential in understanding the population dynamics of coastal upwelling ecosystems and in developing a more solid basis for stock management and conservation.
Food and Chemical Toxicology
Applied Sciences
Mercury (Hg) is globally recognized as a persistent chemical contaminant that accumulates in mari... more Mercury (Hg) is globally recognized as a persistent chemical contaminant that accumulates in marine biota, thus constituting an ecological hazard, as well as a health risk to seafood consumers. Climate change-related stressors may influence the bioaccumulation, detoxification, and toxicity of chemical contaminants, such as Hg. Yet, the potential interactions between environmental stressors and contaminants, as well as their impacts on marine organisms and seafood safety, are still unclear. Hence, the aim of this work was to assess the bioaccumulation of Hg and neuro-oxidative responses on the commercial flat fish species Solea senegalensis (muscle, liver, and brain) co-exposed to dietary Hg in its most toxic form (i.e., MeHg), seawater warming (ΔT°C = +4 °C), and acidification (pCO2 = +1000 µatm, equivalent to ΔpH = −0.4 units). In general, fish liver exhibited the highest Hg concentration, followed by brain and muscle. Warming enhanced Hg bioaccumulation, whereas acidification decr...
Science of The Total Environment
The study aim was to determine a range of relevant persistent and emerging pollutants in oysters ... more The study aim was to determine a range of relevant persistent and emerging pollutants in oysters produced in an aquaculture facility located in an important production area, to assure their safety for human consumption. Pollutants, including 16 PAHs, 3 butyltins (BTs), 29 flame retardants (FRs, including organophosphate and halogenated FRs), 35 pesticides (including 9 pyrethroid insecticides) and 13 personal care products (PCPs, including musks and UV filters), were determined in oysters&#39; tissues collected during one year in four seasonal sampling surveys. The seasonal environmental pollution on the production site was evaluated by water and sediment analysis. Furthermore, oysters&#39; nutritional quality was also assessed and related with the consumption of healthy seafood, showing that oysters are a rich source of protein with low fat content and with a high quality index all year around. Results showed that most analysed pollutants were not detected either in oyster tissues or in environmental matrixes (water and sediments). The few pollutants detected in oyster tissues, including both regulated and non-legislated pollutants, such as a few PAHs (fluorene, phenanthrene, anthracene, fluoranthene, pyrene and indenopyrene), FRs (TPPO, TDCPP, DCP, BDE-47, BDE-209 and Dec 602) and PCPs (galaxolide, galaxolidone, homosalate and octocrylene), were present at low levels (in the ng/g dw range) and did not represent a significant health risk to humans. The observed seasonal variations related to human activities (e.g. tourism in summer) highlights the need for environmental protection and sustainable resource exploration for safe seafood production.
Environmental research, Jan 28, 2017
Marine pollution has been increasing as a consequence of anthropogenic activities. The preservati... more Marine pollution has been increasing as a consequence of anthropogenic activities. The preservation of marine ecosystems, as well as the safety of harvested seafood, are nowadays a global concern. Here, we report for the first time the contamination levels of a large set of 99 emerging and persistent organic contaminants (butyltins (BTs), polycyclic aromatic hydrocarbons (PAHs), pesticides including pyrethroids, pharmaceuticals and personal care products (PCPs) and flame retardants) in roe/gonads of sea urchin Paracentrotus lividus. Sea urchins are a highly prized worldwide delicacy, and the harvesting of this seafood has increased over the last decades, particularly in South West Atlantic coast, where this organism is harvested mainly for exportation. Sampling was performed in three harvesting sites of the NW Portuguese coast subjected to distinct anthropogenic pressures: Carreço, Praia Norte and Vila Chã, with sea urchins being collected in the north and south areas of each site. ...
Food Research International
As bivalve molluscs are filter feeder, often consumed raw or lightly cooked and are frequently cu... more As bivalve molluscs are filter feeder, often consumed raw or lightly cooked and are frequently cultivated in contaminated waters, they are implicated in food-borne disease transmission to human. The present study investigated the potential application of bacteriophage (or phage) phSE-2, phage phSE-5 and phage cocktail phSE-2/phSE-5 to decrease the concentration of Salmonella enterica serovar Typhimurium (Salmonella Typhimurium) during the depuration of natural and artificially contaminated cockles (Cerastoderma edule). Cockles were artificially infected with 105 and 106colony-forming units (CFU)/mL of S. Typhimurium in static seawater and infected group were treated with phages at four different MOI values: 0.1, 1, 10 and 100. Depuration in static seawater at multiplicity of infection (MOI) of 0.1 with single phage suspensions of phSE-2 and phSE-5 provided the best results, as it decreased by ~1.3 and 1.7 logCFU/g, respectively, the concentration of Salmonella spp. after a 4h treatment. At a MOI of 0.1, the rate of inactivation with single phage suspensions was higher when compared with the results obtained using the phage cocktail. However, in naturally contaminated cockles treated in static seawater with single phage suspensions and phage cocktail phSE-2/phSE-5, similar decreases in cultivable bacteria concentration (~0.7-0.9 logCFU/g) were achieved after 6h of treatment. When artificially contaminated cockles were depurated with phage phSE-5 in a recirculated seawater system (mimicking industrial depuration conditions), a 0.9 and 2.0 logCFU/g reduction of Salmonella spp. was reached after 4 and 6h treatment. Once the depuration process was performed without phage, a 6h treatment was needed to obtain a 1.1 logCFU/g reduction of Salmonella spp. Results indicated that combining phage biocontrol with depuration procedures enhance bivalve microbial safety for human consumption by improving decontamination efficiency, proving that this technology can be transposed to the bivalves industry. Moreover, this approach also displays the advantage of reducing the time required for depuration and consequently its associated costs.
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Papers by Maria Leonor Nunes