Percorrer por autor "Delgado, I."
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- Bioactive and nutritional potential of Alaria esculenta and Saccharina latissimaPublication . Afonso, C.; Matos, J.; Guarda, I.; Gomes-Bispo, A.; Gomes, R.; Cardoso, C.; Gueifão, S.; Delgado, I.; Coelho, Inês; Castanheira, Isabel; Bandarra, N.M.The brown seaweed species Alaria esculenta and Saccharina latissima are commercial edible resources in Norway. There are knowledge gaps regarding these species. Accordingly, they were characterized and their bioactivity and bioaccessibility evaluated. The fatty acid (FA) analysis revealed anω-3/ω-6 ratio of almost 2 in A. esculenta vs 1 in S. latissima. The FAs 18:4ω-3 (stearidonic acid) and 20:5ω-3 (eicosapentaenoic acid) were themain contributors to the relativeω-3 polyunsaturated FA richness in A. esculenta. This seaweed was also rich in fucoxanthin (66.1 ± 20.1 mg (100 g)−1 dw), representing approximately 4.1% of the total lipids. Hence, this species may be a source of natural fucoxanthin. Anti-inflammatory activity was significantly stronger (p < 0.001) in the ethanolic than in the aqueous extracts of the algal biomass, 48.3–60.4% vs 18.2–38.6% cyclooxygenase-2 (COX-2) inhibition. In the bioaccessible fraction of both species, phenolic content and antioxidant activitywere low.Moreover, the anti-inflammatory capacity was largely lost in this fraction, especially in the case of S. latissima. Regarding elemental composition, there were no large differences between the two brown seaweed species, being As levels high (53.11–58.93 mg kg−1 dw). However, this As is mostly organic and accordingly poses a lower risk to human health. The I content was high, especially in S. latissima, 2829 ± 58 mg kg−1 dw (557 ± 17 mg kg−1 dw in A. esculenta). Taking into account I levels, only 0.05 g and 0.39 g of S. latissima per day (based on I levels before digestion) are enough to reach I DRI and I TUIL, respectively, or 0.07 g and 0.57 g per day (based on I levels after digestion), for I DRI and I TUIL, respectively. The attained results point to an untapped potential regarding development of functional foods and other products with high-added value—particularly in the case of A. esculenta.
- Bracketing versus multipoint calibration in determination of isocyanates in agglomerated cork stoppersPublication . Delgado, I.; André, C.; Ramos, A.; Matos, A.S.; Stockham, K.; Kumaran, S.; Castanheira, I.A calibration method was developed for the quantification of isocyanates in cork stoppers agglomerates. Bracketing and multipoint calibration curve was applied to a in-house optimized UPLC/DAD analytical method. The calibration curves were obtained by regression analysis using experimental points that covers the range of concentrations expected in real samples. A contaminated real sample was injected and MDI concentration was 6.2 % and 6.4% when calibration methods to calculate the content were multipoint or bracketing, respectively. According with our results both methods are complementary and necessary to guarantee the reliably of results obtained by chromatographic procedure.
- Characterization of food from burnt areas in the Central Region of PortugalPublication . Gueifão, S.; Moreira, T.; Ventura, M.; Delgado, I.; Coelho, I.; Castanheira, I.AIM: Forest fires constitute an environmental problem with adverse and diversified impacts on atmospheric, terrestrial, and aquatic ecosystems, with economic and social repercussions, and a significant impact on flora. Fire mineralizes soil nutrients and returns plant-locked nutrients to the soil. Nutrients are lost from the ecosystem through the release of particulates and volatile compounds during the fire, and later through surface transport and leaching by rains1. Wildfires can play an important role in the environmental distribution of major and trace elements, including through their mobilization by fire-induced runoff and associated transport of soil and ash particles. Also, wildfires have been found to release and deposit contaminants on the soil surface, either directly by combustion of vegetation and mineralization of soil organic matter or indirectly through interactions of ashes. This fact can lead to the addition of potentially significant amounts of these elements in the soil and, thereby, can alter its chemical properties2. This study aims to evaluate the content of arsenic (As), cadmium (Cd) and chromium (Cr) in cabbage, potatoes, eggs and fruit samples cultivated in recently burnt areas. MATERIAL AND METHODS: A total of 24 pools composed of 3 samples each was analysed at three different harvest periods. Cabbage samples from burnt zones were compared with a designated control sample from a non-burnt zone. Analytical determinations were performed by Inductive Plasma Coupled Mass Spectrometry (ICP-MS). Previously, samples underwent a heating block acid digestion with a validated time and temperature program. Speciation analysis was carried out by High Performance Liquid Chromatography (HPLC) coupled to ICP-MS. Before analysis, samples were extracted using nitric acid. Analyses were performed in accordance with ISO 17025:2005. RESULTS: The concentrations of As in fruits and Cd in eggs were below the limit of quantification (2.2 µg/kg and 3.1 µg/kg, respectively). The variation of Cr content between matrices was as follows: fruits > eggs > cabbages > potatoes. On the other hand, As contents was verified as: cabbage > eggs > potatoes > fruit. Cabbage presented the highest Cd content, while eggs had the lowest values for this element. When compared to the control sample, the most pronounced rise was observed for As. Speciation studies show that the predominant arsenic species in cabbages are also the most toxic ones, that is, arsenite (As (III)) and arsenate (As (V)). CONCLUSIONS: The values of the inorganic elements present in this study are not yet properly legislated so it is important to performed studies able to support future legal references. Monitoring studies based on accredited methods are a powerful aid in assessing the risk exposure of affected populations.
- Elemental composition and in vitro bioaccessibility assessment of holothuroidsPublication . Sales, S.S.; Lourenço, H.M.; Bandarra, N.M.; Cardoso, C.; Brito, P.; Botelho, M.J.; Gonçalves, S.; Coelho, I.; Delgado, I.; Pessoa, M.F.; Félix, P.M.; Afonso, C.The elemental composition and bioaccessibility of the wild holothuroids Holothuria arguinensis, Holothuria forskali, and Holothuria mammata was studied. Nutritional and toxicological aspects were evaluated. H. mammata was the richest in Mn, Ni, As, Cd, Pb, and Hg; H. forskali had the highest Cu and I contents, 4.12–4.93 mg/kg dw and 28.02–28.26 mg/kg dw, respectively; and Summer H. arguinensis had high Se content, 4.26 ± 0.08 mg/kg dw. Holothuroids as food may be a dietary Se and I source, with Pb as main hazard. In order to meet the Se Recommended Daily Allowance (RDA), 15–18 g of dried H. arguinensis and 18–33 g of dried H. mammata would have to be consumed everyday. For I, 10 g of dried H. arguinensis, 6–11 g of dried H. forskali, and 20–21 g of dried H. mammata everyday would be required to achieve the I Dietary Recommended Intake (DRI). For meeting Cu dietary requirements, consumption frequencies would have to exceed 330 g dw/day in the most favourable case (Winter H. forskali). Regarding other essential elements, quantities would be much higher. Regarding contaminants, a consumption above 20–21 g/day of dried H. mammata would constitute a Pb risk. Overall, holothuroids can substantially contribute to elemental nutritional requirements.
- Farming a wild seaweed and changes to its composition, bioactivity, and bioaccessibility: The Saccorhiza polyschides case studyPublication . Cardoso, C.; Almeida, J.; Coelho, I.; Delgado, I.; Gomes, R.; Quintã, R.; Bandarra, N.M.; Afonso, C.The nutritional value, elemental and fatty acid composition as well as key biological activities were determined in a large brown seaweed species (Saccorhiza polyschides, abundant in European shores), taking into account the effects of wild vs farmed and land-based vs open sea Integrated Multi-Trophic Aquaculture (IMTA) system dichotomies. The results showed that S. polyschides has significant amounts of relevant nutrients, some biological activity (anti-inflammatory), high contents of the essential elements Se (1.07–1.79 mg/kg dw) and I (367–522 mg/kg dw), and a high bioaccessibility of I. However, As levels should be monitored, given their high bioaccessibility (∼60–70% range), and I levels may translate into excessive I intake if too much seaweed is consumed (if daily consumption of dried S. polyschides exceeds 3 g dw). Regarding the wild-farmed dichotomy, wild S. polyschides had a moderately higher nutritional value, including a better ω3/ω6 ratio, but a lower Se content than farmed S. polyschides, 0.80 ± 0.01 vs 0.58–0.69 and 1.07 ± 0.05 vs 1.16–1.79 mg/kg dw, respectively. Furthermore, bioaccessibility of elements was not much affected by cultivation. Concerning land-based vs open sea IMTA, in comparison to S. polyschides in earthen ponds, lower Hg and Pb contamination, but higher Cd levels were determined in the seaweed cultivated in open sea. S. polyschides farming per se did not have a large deleterious impact on the characteristics of this edible seaweed and may ensure the production of large amounts of algal biomass for feed, food, and nutraceutical applications.