Browsing by Author "Bandarra, Narcisa"
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- Fatty acid profiles of the main lipid classes of green seaweeds from fish pond aquaculturePublication . Cardoso, Carlos; Ripol, Andrea; Afonso, Claudia; Freire, Margarida; Varela, João; Quental-Ferreira, Hugo; Pousao-Ferreira, Pedro; Bandarra, NarcisaThe lipid composition of five species of green seaweeds (Chaetomorpha linum, Rhizoclonium riparium, Ulva intestinalis, Ulva lactuca, and Ulva prolifera) grown in fish pond aquaculture systems was studied. In particular, the overall fatty acid (FA) profile and the FA profile of each main lipid class found in these seaweed species were thoroughly analyzed. It was found that every seaweed had a specific FA profile, whose specificities were rendered more obvious with the study of the FA profile per lipid class. However, between U.lactuca and U.intestinalis, there were only minor differences. Nonetheless, it was possible to identify significant differences between the palmitic acid content in the phospholipid (PL) and glycolipid (GL) classes of each seaweed. A clear distinction between the FA profiles of R.riparium and C.linum, which belong to the Cladophorales order, and those of Ulva genus, Ulvales order, was also determined. Moreover, there were also differences among lipid classes, yielding large contrasts between PLs+GLs and triacylglycerols (TAGs) as well as between monoacylglycerols (MAGs) and free fatty acids (FFAs). This study also found evidence supporting the location of particular FAs in specific TAG positions. FA profiles have the potential to be used as a chemotaxonomic tool in green seaweeds, providing a simple method to check authenticity of seaweed used as food.
- Halophytes: Gourmet food with nutritional health benefits?Publication . Barreira, Luísa; Resek, Eva; Rodrigues, Maria Joao; Rocha, Maria Isabel; Pereira, Hugo; Bandarra, Narcisa; da Silva, Manuela Moreira; J. C. or Varela J. or Varela J.C.S., Varela; Custodio, LuisaAlthough little is known about their nutritional composition, Sarcocornia perennis subsp. perennis, S. perennis subsp. alpini and Salicornia ramosissima (Salicorniaceae) as well as Arthrocnemum macro-stachyum (Amaranthaceae) are consumed in gourmet cuisine. In spite of belonging to different families, these halophytes share morphological and organoleptic characteristics. This work explored the nutritional properties and the antioxidant potential of these species using five integrative methods. All species had a nutritional profile suitable for human consumption with high levels of protein (5.20-13.2 g/100 g dw) and n-3 polyunsaturated fatty acids (FA), particularly or alpha-linolenic acid (19.3-25.9% of total FA), and low concentration of toxic metals (below the limits imposed by the European Commission). These halophytes are also a good source of minerals, particularly sodium (64.1-109 mg/gdw), and S. ramosissima is an excellent source of manganese (204 mu g/g dw). However, due care should be taken not to exceed the legal limits for sodium ingestion. These plants showed also significant antioxidant potential, with high radical scavenging activity (RSA), iron reducing power and total phenolics content (20.5-49.2 mg GAE/g). A. macrostachyum had the highest RSA (lC(50-DPPH) = 0.84 mg/mL; IC50-NO = 0.60 mg/mL), and iron reducing potential (IC50= 0.84 mg/mL) along with high levels of alpha- and gamma-tocopherol (8.74 and 4.71 mg/100 g dw, respectively). (C) 2017 Elsevier Inc. All rights reserved.
- 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.
- Teleost fish larvae adapt to dietary arachidonic acid supply through modulation of the expression of lipid metabolism and stress response genesPublication . Alves Martins, Dulce; Rocha, Filipa; Martinez-Rodriguez, Gonzalo; Bell, Gordon; Morais, Sofia; Castanheira, Maria Filipa; Bandarra, Narcisa; Coutinho, Joana; Yufera, Manuel; Conceicao, LuisDietary fatty acid supply can affect stress response in fish during early development. Although knowledge on the mechanisms involved in fatty acid regulation of stress tolerance is scarce, it has often been hypothesised that eicosanoid profiles can influence cortisol production. Genomic cortisol actions are mediated by cytosolic receptors which may respond to cellular fatty acid signalling. An experiment was designed to test the effects of feeding gilthead sea-bream larvae with four microdiets, containing graded arachidonic acid (ARA) levels (0.4, 0.8, 1.5 and 3.0 %), on the expression of genes involved in stress response (steroidogenic acute regulatory protein, glucocorticoid receptor and phosphoenolpyruvate carboxykinase), lipid and, particularly, eicosanoid metabolism (hormone-sensitive lipase, PPAR alpha, phospholipase A(2), cyclo-oxygenase-2 and 5-lipoxygenase), as determined by real-time quantitative PCR. Fish fatty acid phenotypes reflected dietary fatty acid profiles. Growth performance, survival after acute stress and similar whole-body basal cortisol levels suggested that sea-bream larvae could tolerate a wide range of dietary ARA levels. Transcription of all genes analysed was significantly reduced at dietary ARA levels above 0.4%. Nonetheless, despite practical suppression of phospholipase A(2) transcription, higher leukotriene B-4 levels were detected in larvae fed 3.0% ARA, whereas a similar trend was observed regarding PGE(2) production. The present study demonstrates that adaptation to a wide range of dietary ARA levels in gilthead sea-bream larvae involves the modulation of the expression of genes related to eicosanoid synthesis, lipid metabolism and stress response. The roles of ARA, other polyunsaturates and eicosanoids as signals in this process are discussed.