Browsing by Author "Coelho, I."
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- Assessment of the mechanisms and pathways of fish contamination and mercury-selenium antagonismPublication . Ribeiro, M.; Zephyr, N.; Leufroy, A.; Coelho, I.; Danion, M.; Castanheira, I.; Guerin, T.; Jitaru, P.AIM Mercury (Hg) is one of the most dangerous chemical contaminants for humans and the environment. This is due to its extreme toxicity, particularly in the methylated form, denominated methylmercury (CH3Hg), which is easily absorbed by the body (bioaccumulation). CH3Hg is present in low concentrations in water and in water sediments, and can greatly increase its concentration in aquatic organisms, often reaching more than 85% of total Hg. Therefore, the main source of exposure to CH3Hg is fish consumption, in particular fish from higher trophic levels, since its content tends to increase along the food chain (biomagnification). Nevertheless, it is interesting to note that mercury´s bioavailability seems to be linked to selenium (Se) levels. The Se protective effects against Hg bioaccumulation and toxicity has been identified for the last decades, although the mechanism is still poorly understood. The aim of this study is to accurately assess the Hg-Se interaction in fish and the human dietary exposure. MATERIAL AND METHODS A bioassay was carried out in a representative freshwater fish (rainbow trout) in collaboration with the fish viral pathology unit of ANSES (Ploufragan-Plouzané laboratory). Fish were dietary exposed to CH3Hg under controlled conditions, in the presence or absence of SeMet. The final concentration of CH3Hg and SeMet in the diets was respectively 0,2 μg g-1 and 5 μg g-1. Briefly, six feeding protocols were compared: a non-supplemented diet (control group), a diet supplemented with SeMet, a diet supplemented with MeHg, a diet supplemented with both MeHg and SeMet, a diet supplemented first with MeHg for 1 month and then with SeMet for 2 months and a diet supplemented with SeMet for 1 month and then with MeHg for 2 months. The edible part of fish (muscle) was analysed for SeT and Hgt concentrations by ICP-MS after different time of exposure (1 month, 2 months and 3 months).
- Building a database for provenance studies of origin wines from the Douro ValleyPublication . Coelho, I.; Matos, A.; Nascimento, A.; Bordado, J.; Donard, O.; Epova, E.; Barre, J.; Berail, S.; Castanheira, I.AIM: The aim of the present work is to produce high quality analytical data suitable for evaluating the provenance of Port wine and Douro wine and integrating an authentic wine reference database. Both wines are produced within the same geographical area, the Douro Valley region located in the northeast of Portugal but follow different vinification procedures. The fermentation of Port wine is interrupted by the addition of a grape based spirit producing a sweet fortified wine typically consumed as digestif and dessert wine. Douro wine, on the other hand, is a table wine. The mineral composition of plants reflects the soil and the environmental conditions under which plants were grown. Minerals and trace elements, as well as some of their isotopes, are potential biomarkers in authenticity studies. We followed two analytical strategies, multielemental analysis and stable isotopes, to understand the parameters common to the region and fundamentally dependent on the soils and the ones influenced by processing methods or environmental contamination. MATERIAL AND METHODS: Fifteen samples of each type of wine, Port and Douro, were characterized for 26 elements. 7Li, 9Be, 11B, 27Al, 52Cr, 55Mn, 59Co, 60Ni, 65Cu, 66Zn, 75As, 77Se, 85Rb, 88Sr, 95Mo, 107Ag, 111Cd, 118Sn, 205Tl, 208Pb were determined by inductively coupled plasma mass spectrometer (ICP-MS) while Fe, Mg , P , Ca , Na , K were analysed by inductively coupled plasma optical emission spectrometer (ICP-OES). In addition, two isotopic systems were also studied: 87Sr/86Sr and 18O determined by Multicollector-ICP-MS (MC-ICP-MS) and Isotope Ratios Mass Spectrometry (IRMS), respectively. For all analysis reagents used were of high purity to prevent for contaminations. Ultra pure water of grade I, as defined in EN ISO 3696, was obtained using a Milli-Q plus Millipore System. Concentrated nitric acid, analytical grade (65%; Merck), was purified in the laboratory, using an acid distillation system (Milestone SubPUR), and compared to a commercial ultrapure nitric acid solution (Merck), on a routine basis. Analytical results were combined with chemometric tools, Principal Components Analysis (PCA) and Hierarchical Cluster Analysis (HCA), capable of performing multivariate data analysis. RESULTS: Ag, Cd and Tl were mostly below the level of quantification and were therefore removed from statistical analysis. 87Sr/86Sr varied between 0,71652 and 0,72290. PCA revealed 6 principal components that explained 84,6% of the total variance. CONCLUSIONS: The vinification method did not affect significantly stable isotopes, either 87Sr/86Sr or 18O. On the other hand, some elements; namely Cr, Co, Cu, Rb, Se, Ca and Na; showed significant differences between the two types of wine. The produced data can be integrated into an authenticity system for Port and Douro wines.
- 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.
- Composition and bioaccessibility of elements in green seaweeds from fish pond aquaculturePublication . Afonso, C.; Cardoso, C,; Ripol, A.; Varela, J.; Quental-Ferreira, H.; Pousão-Ferreira, P.; Ventura, M.S.; Delgado, I.M.; Coelho, I.; Castanheira, I.; Bandarra, N.M.The elemental composition of five species of green seaweeds (Chaetomorpha linum, Rhizoclonium riparium, Ulva intestinalis, Ulva lactuca, Ulva prolifera) grown in fish pond aquaculture systems were studied. The elemental bioaccessibility in these species was also investigated through the application of an innovative in vitro digestive model of the human gastrointestinal tract. It was observed that R. riparium had the highest levels of Mn, Sr, Cd, Sn, and I and that U. lactuca had the highest Ni and Cu concentrations. The daily amounts of dried green seaweed required for achieving specific dietary intakes were calculated, namely: 7 g of dried U. lactuca (for meeting Cu Recommended Daily Allowance, RDA); 173 g of dried U. lactuca (Zn RDA); 78 g of dried C. linum (Se RDA); 41 g of dried C. linum (Mo RDA); and 0.5 g of dried R. riparium (I Dietary Reference Intake, DRI). Concerning elemental bioaccessibility, Mn and Cu had the highest values, always above 50%, I values were in the lower range, between 14 and 31%. The elemental bioaccessibility range of R. riparium (31–100%) was higher than the ranges for other species, particularly C. linum (0–56%). The bioaccessibility results entailed higher quantities of dried seaweed for reaching dietary intakes: 10 g of dried U. lactuca (Cu RDA); 290 g of dried R. riparium (Zn RDA); and 2 g of dried R. riparium (I DRI). Accordingly, R. riparium is a very rich I source. This study showed the importance of taking into account bioaccessibility results in estimating dietary intakes.
- 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.
- Mackerel seasonality effect on Se contentPublication . Rego, A.; Ventura, M.; Gueifão, S.; Coelho, I.; Cardoso, C.; Afonso, C.; Bandarra, N.; Castanheira, I.Selenium is an essential micronutrient that can become toxic when ingested in high concentrations The human being can obtain Se through the consumption of food, dietary supplements, water and exposure to ambient air The food source is the most abundant and the main contributor to the daily intake of Se in Fish is one of the best sources of Se, and the Portuguese Mackerel is one of the most important and abundant species in Portugal It is rich in several vitamins and Se, due to being a predator The work presented integrates part of the first task of the project Newfood 4 thought that aims at the prevention of cognitive decline through nutrient combination. The aim is to study of the influence of seasonality in the levels of Se in Mackerel samples collected throughout the year. With the exception of May, Se content in mackerel remained constant throughout the year The high Se content found in May samples may be related to mackerel ´ s spawning season and feeding habits However, further studies are needed to confirm these preliminary conclusions, namely studying the Se content monthly for several years
- Resultados Minerais TDS Na, K, Ca, P, Fe , MgPublication . Nascimento, A.; Santiago, S.; Coelho, I.; Ventura, M.; Gueifão, S.; Coelho, M.Foram analisadas 229 amostras, por ICP-OES para a determinação dos teores de minerais: Na, K, Ca, P, Fe, Mg.
- Seasonal variation of chub mackerel (Scomber colias) selenium and vitamin B12 content and its potential role in human healthPublication . Rego, A.; Coelho, I.; Motta, C.; Cardoso, C.; Gomes-Bispo, A.; Afonso, C.; Prates, J.A.M.; Bandarra, N.M.; Silva, J.A.L.; Castanheira, I.Chub mackerel (Scomber colias), an underutilised fish species, has been identified as an excellent source of selenium and vitamin B12, which may prevent and delay cognitive decline and dementia. Given these nutrients’ contents seasonal variability, a complete monthly sampling, involving a specifically adjusted methodology for the determination of vitamin B12 (LC-MS/MS) and its main vitamers and a sensitive analytical technique (ICPMS) for Se, was carried out. Regarding total vitamin B12 in the chub mackerel muscle, its content varied from 10.0 ± 1.0 μg/100 g in February to 18.9 ± 1.9 μg/100 g in August. It was also shown that methylcobalamin content ranged from 1.12 ± 0.43 (March) to 6.77 ± 0.80 μg/100 g (August), a sixfold increase. Hydroxocobalamin content varied between 3.49 ± 0.12 (February) and 9.62 ± 0.41 μg/100 g (August). The content of Se also had seasonal variability, ranging from 451 ± 14 μg/kg (December) to 606 ± 11 μg/kg (July). In the worst-case scenario, a weekly 160 g meal of this fish would almost guarantee B12 requirements. Three weekly 160 g meals of S. colias would cover, at least, 56% of the Se requirements. Therefore, as first explored here, it is highly relevant a complete, year-round assessment of the chub mackerel’s nutritional value, in order to elaborate finely tuned dietary recommendations.
- Seasonality as experienced in the market and the resulting variation in the amino acid and elemental composition of chub mackerel (Scomber colias)Publication . Motta, C.; Rego, A.; Cardoso, C.; Coelho, I.; Gomes-Bispo, A.; Afonso, C.; Prates, J.A.M.; Castanheira, I.; Bandarra, N.Chub mackerel (Scomber colias) is an underutilised fish species, abundant in the Atlantic Ocean. Its amino acid profile and elemental composition are still insufficiently studied. Accordingly, these aspects were studied on a monthly basis. The most abundant essential amino acids, lysine and leucine, had contents ranging from 1270 ± 40 mg/100 g in August to 1820 ± 96 mg/100 g in November and from 1210 ± 36 mg/100 g in August to 1570 ± 20 mg/100 g in March, respectively. The other essential amino acids’ contents varied between 500 and 1200 mg/ 100 g. Essential amino acids represented between 41.9 % and 44.6 % of all amino acids. As a result of high histidine content in S. colias, three weekly meals (160 g/meal) guarantee all human histidine requirements. Regarding elemental composition, K was the most abundant, varying its content between 331 ± 3 mg/100 g and 499 ± 4 mg/100 g. The other studied elements’ order of abundance was P > Na > Mg > Ca > Fe > Zn. Under optimal conditions, consumption of a 160 g daily meal of S. colias may provide at most 20 % of the Fe and 30 % of the Zn requirements. Therefore, though not an outstanding Fe and Zn source, S. colias can give a significant contribution to these elements’ requirements
