Percorrer por autor "Gonçalves, Amparo"
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- Dietary creatine supplementation in gilthead seabream (Sparus aurata): comparative proteomics analysis on fish allergens, muscle quality, and liverPublication . Schrama, Denise; Cerqueira, Marco; Raposo de Magalhães, Cláudia; Rosa Da Costa, Ana; Wulff, Tune; Gonçalves, Amparo; Camacho, Carolina; Colen, R.; Fonseca, Flávio; Rodrigues, PedroThe quality of fish flesh depends on the skeletal muscle's energetic state and delaying energy depletion through diets supplementation could contribute to the preservation of muscle's quality traits and modulation of fish allergens. Food allergies represent a serious public health problem worldwide with fish being one of the top eight more allergenic foods. Parvalbumins, have been identified as the main fish allergen. In this study, we attempted to produce a low allergenic farmed fish with improved muscle quality in controlled artificial conditions by supplementing a commercial fish diet with different creatine percentages. The supplementation of fish diets with specific nutrients, aimed at reducing the expression of parvalbumin, can be considered of higher interest and beneficial in terms of food safety and human health. The effects of these supplemented diets on fish growth, physiological stress, fish muscle status, and parvalbumin modulation were investigated. Data from zootechnical parameters were used to evaluate fish growth, food conversion ratios and hepatosomatic index. Physiological stress responses were assessed by measuring cortisol releases and muscle quality analyzed by rigor mortis and pH. Parvalbumin, creatine, and glycogen concentrations in muscle were also determined. Comparative proteomics was used to look into changes in muscle and liver tissues at protein level. Our results suggest that the supplementation of commercial fish diets with creatine does not affect farmed fish productivity parameters, or either muscle quality. Additionally, the effect of higher concentrations of creatine supplementation revealed a minor influence in fish physiological welfare. Differences at the proteome level were detected among fish fed with different diets. Differential muscle proteins expression was identified as tropomyosins, beta enolase, and creatine kinase among others, whether in liver several proteins involved in the immune system, cellular processes, stress, and inflammation response were modulated. Regarding parvalbumin modulation, the tested creatine percentages added to the commercial diet had also no effect in the expression of this protein. The use of proteomics tools showed to be sensitive to infer about changes of the underlying molecular mechanisms regarding fish responses to external stimulus, providing a holistic and unbiased view on fish allergens and muscle quality.
- Dietary tools to modulate glycogen storage in gilthead seabream muscle: glycerol supplementationPublication . Silva, Tomé S.; Matos, Elisabete; Cordeiro, O.; Colen, Rita; Wulff, Tune; Sampaio, Eduardo; Sousa, Vera; Valente, L. M. P.; Gonçalves, Amparo; Silva, Joana M. G.; Bandarra, N.; Nunes, Maria Leonor; Dinis, Maria Teresa; Dias, J.; Jessen, Flemming; Rodrigues, PedroThe quality and shelf life of fish meat products depend on the skeletal muscle’s energetic state at slaughter, as meat decomposition processes can be exacerbated by energy depletion. In this study, we tested dietary glycerol as a way of replenishing muscle glycogen reserves of farmed gilthead seabream. Two diets were tested in duplicate (n = 42/tank). Results show 5% inclusion of crude glycerol in gilthead seabream diets induces increased muscle glycogen, ATP levels and firmness, with no deleterious effects in terms of growth, proximate composition, fatty acid profile, oxidative state, and organoleptic properties (aroma and color). Proteomic analysis showed a low impact of glycerol-supplementation on muscle metabolism, with most changes probably reflecting increased stress coping capacity in glycerol-fed fish. This suggests inclusion of crude glycerol in gilthead seabream diets (particularly in the finishing phase) seems like a viable strategy to increase glycogen deposition in muscle without negatively impacting fish welfare and quality.
- Effect of creatine and EDTA supplemented diets on European seabass (Dicentrarchus labrax) allergenicity, fish muscle quality and omics fingerprintPublication . Schrama, Denise; Raposo de Magalhães, Cláudia; Cerqueira, Marco; Carrilho, Raquel; Farinha, Ana Paula; Costa, Ana Rosa da; Gonçalves, Amparo; Kuehn, Annette; Revets, Dominique; Planchon, Sébastien; Engrola, Sofia; Rodrigues, PedroThe relatively easy access to fish worldwide, alongside the increase of aquaculture production contributes to increased fish consumption which result in higher prevalence of respective allergies. Allergies to fish constitute a significant concern worldwide. beta-parvalbumin is the main elicitor for IgE-mediated reactions. Creatine, involved in the muscle energy metabolism, and ethylenediamine tetraacetic acid (EDTA), a calcium chelator, are potential molecules to modulate parvalbumin. The purpose of this study was to test creatine (2, 5 and 8%) and EDTA (1.5, 3 and 4.5%) supplementation in fish diets to modulate beta-parvalbumin expression and structure and its allergenicity in farmed European seabass (Dicentrarchus labrax) while assessing its effects on the end-product quality. Fish welfare and muscle quality parameters were evaluated by plasma metabolites, rigor mortis, muscle pH and sensory and texture analysis. Proteomics was used to assess alterations in muscle proteome profile and metabolic fingerprinting by Fourier transform infrared spectroscopy was used to assess the liver metabolic profile. In addition, IgE-reactivity to parvalbumin was analysed using fish allergic patient sera. Metabolic fingerprinting of liver tissue revealed no major alterations in infrared spectra with creatine supplementation, while with EDTA, only absorption bands characteristic of lipids were altered. Comparative proteomics showed up regulation of (tropo) myosin and phosphoglycerate mutase 2 with Creatine supplementation. In the case of EDTA proteomics showed up regulation of proteins involved in cellular and ion homeostasis. Allergenicity seems not to be modulated with creatine or EDTA supplementation as no decreased expression levels were found and IgE-binding reactivity showed no quantitative differences.
- Influence of supplemental maslinic acid (olive-derived triterpene) on the post-mortem muscle properties and quality traits of gilthead seabreamPublication . Matos, Elisabete; Silva, Tomé S.; Wulff, Tune; Valente, L. M. P.; Sousa, Vera; Sampaio, Eduardo; Gonçalves, Amparo; Silva, Joana M. G.; Dinis, Maria Teresa; Rodrigues, Pedro; Dias, J.Maslinic acid, a natural triterpene, was evaluated as a dietary supplement to modulate glycogen post-mortem mobilization in gilthead seabream muscle. For this purpose, a multidisciplinary trial was undertaken, where flesh quality criteria, as well as biochemical and histological parameters, enzymatic activities and protein expression in the muscle were assessed. Supplementing gilthead seabream diets with maslinic acid mainly resulted in hypertrophy of muscle fibres and inhibition of cathepsin B activity, with no observed differences in terms of glycogen and ATP content of the muscle, as well as glycogen phosphorylase activity. Proteomic analysis showed a low impact of maslinic acid supplementation on muscle metabolism, with most changes reflecting increased stress coping capacity and muscle hypertrophy in maslinic acid-fed fish. As a finishing strategy to improve the muscle's energetic status, the usefulness of maslinic acid seems limited. However, it shows potential for promoting muscle growth in this species.
- Natural fortification fortification of trout with dietary macroalgae and selenised-yeast increases the nutritional contribution in iodine and seleniumPublication . Ribeiro, Ana Ramalho; Gonçalves, Amparo; Bandarra, Narcisa; Nunes, Maria Leonor; Dinis, Maria Teresa; Dias, Jorge; Rema, PauloFish and seafood consumption are increasing worldwide and the contribution of aquaculture products to consumers' diets is significant. External feeding in aquaculture unlocks the possibility of tailoring fish products with health beneficial compounds. A study was undertaken to evaluate the feed fortification with an iodine rich macroalgae (Laminaria digitata) and selenised yeast, at its maximum permitted levels, on minerals and vitamins content in rainbow trout edible part. Dietary supplementation resulted in a six-fold increase for iodine and a 2.9-fold increase for selenium contents in trout fillets without altering sensorial traits. The fortified fish presented a nutritional contribution of 12.5% DRI for iodine and 78% DRI for selenium, but all produced fish could supply 80% DRI for vitamin D3. Overall, fish from this trial could be labelled as "high in selenium and high in vitamin D3" under the EFSA definition for a functional food. (C) 2016 Elsevier Ltd. All rights reserved.
- Phaeodactylum tricornutum in finishing diets for gilthead seabream: effects on skin pigmentation, sensory properties and nutritional valuePublication . Ribeiro, Ana Ramalho; Gonçalves, Amparo; Barbeiro, Mónica; Bandarra, Narcisa; Nunes, Maria Leonor; Carvalho, Maria Luisa; Silva, Joana; Navalho, João; Dinis, Maria Teresa; Silva, Tome; Dias, JorgeMicroalgal biomasses are known to play a major role in fish pigmentation, which is particularly important in farmed fish, since colour and external appearance are the first cue for customers when choosing seafood. A study was undertaken to assess the potential of microalgae biomass from the diatom Phaeodactylum tricornutum as a functional ingredient for gilthead seabream (Sparus aurata) feeds. Three experimental diets were designed: a control diet (CTRL), this same diet supplemented with 2.5% of P. tricornutum wild strain (diet MA20); and a third diet with 2.5% of P. tricornutum biomass (diet MA37) cultivated under different temperature and light regimes that resulted in higher levels of fucoxanthin. Microalgae diets led to a reduction (P < 0.05 in MA37) of whole-body fat and lower lipid retention (P < 0.05 in MA20 and MA37). Microalgae did not impact odour, flavour, whiteness, and fatness perception in cooked fillets. Overall, colour analysis showed that P. tricornutum biomass led to significant differences compared to control in specific areas: the MA37 diet induced a significantly (P < 0.05) lighter and more vivid yellow colouration of seabream operculum (Delta E* approximate to 5) perceptible to the human eye; ventral skin lightness was also affected by the dietary treatments (P = 0.040), being higher for microalgae-fed groups, though this difference was not perceptually strong (Delta E* approximate to 1.7). Phaeodactylum tricornutum biomass can be used as a functional ingredient, improving external pigmentation and thus contributing to meet consumer expectations in relation to farmed gilthead seabream.
- Reproductive success in the Lusitanian toadfish: influence of calling activity, male quality and experimental designPublication . Amorim, M. Clara P.; Conti, Carlotta; Sousa-Santos, Carla; Novais, Bruno; Gouveia, Maria D.; Vicente, Joana R.; Modesto, Teresa; Gonçalves, Amparo; Fonseca, Paulo J.Acoustic signals are sexual ornaments with an established role on mate choice in several taxa, but not in fish. Recent studies have suggested that fish vocal activity may signal male quality and influence male's reproductive success but experimental evidence is lacking. Here we made two experiments to test the hypothesis that vocal activity is essential for male breeding success in a highly vocal fish, the Lusitanian toadfish. We first compared the reproduction success between muted and vocal males. In a second experiment we related male reproduction success with acoustic activity and male quality, including biometric, condition and physiological features. As a proxy for reproductive success we tallied both total number and number of sired eggs, which were correlated. Muting experiments showed that successful mating was dependent on vocalizing. In addition, the number of eggs was positively associated with the male's maximum calling rate. In the second experiment male's reproductive success was positively associated with male condition and negatively related with circulating androgen levels and relative gonad mass, but was not associated with vocal activity. Differences in results may be related with nest design which could have influenced mate choice costs and intra-sexual competition. In the muting experiment nests had a small opening that restrained the large nest-holder but allowed smaller fish, such as females, to pass while in the second experiment fish could move freely. These experiments suggest that a combination of factors, including vocal activity, influence reproductive success in this highly vocal species. (C) 2015 Elsevier Inc. All rights reserved.