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1.
Chemosphere ; 242: 125289, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31896204

RESUMO

Selenium (Se) and zinc (Zn) are essential microelements for humans with crucial biological functions. In this study, we determined Se and Zn concentrations in soils and rice grains on Hainan Island and investigated how their spatial distributions are related to soil mineral elements, topography, and vegetation coverage. Overall, the concentrations of Se and Zn in soils were higher than the background values for Chinese soil; the Se concentrations in rice grains were higher than the threshold value for Se deficiency in grains, but Zn concentrations were lower than the proposed critical concentration. Both Spearman's correlation and stepwise regression analysis showed that the concentrations of soil Fe and Ca significantly affected soil Se and Zn: a difference of 1 g kg-1 in soil Fe changed soil Se by 2.820 µg kg-1 and soil Zn by 0.785 mg kg-1, respectively, while a difference of 1 g kg-1 in soil Ca changed soil Se by 3.249 µg kg-1 and soil Zn by 0.356 mg kg-1, respectively. For rice grains, Se and Zn concentrations decreased with increasing elevation; every 100 m increase in elevation could decrease Se by 0.022 mg kg-1 and Zn by 0.912 mg kg-1. Moreover, the impact of Fe and Ca on soil Zn was relatively strong in the northeast region, while the influence of elevation on rice grain Se was more significant in the central region. The findings contribute to a better understanding of factors driving the distribution of Se and Zn in soils and crops.


Assuntos
Grão Comestível/química , Monitoramento Ambiental/métodos , Oryza/química , Selênio/análise , Solo/química , Zinco/análise , Altitude , Cálcio/análise , China , Humanos , Ferro/análise , Ilhas , Análise de Regressão , Análise Espacial
2.
Chem Soc Rev ; 49(1): 143-179, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31750471

RESUMO

Metal cations and anions are essential for versatile physiological processes. Dysregulation of specific ion levels in living organisms is known to have an adverse effect on normal biological events. Owing to the pathophysiological significance of ions, sensitive and selective methods to detect these species in biological systems are in high demand. Because they can be used in methods for precise and quantitative analysis of ions, organic dye-based ratiometric fluorescent probes have been extensively explored in recent years. In this review, recent advances (2015-2019) made in the development and biological applications of synthetic ratiometric fluorescent probes are described. Particular emphasis is given to organic dye-based ratiometric fluorescent probes that are designed to detect biologically important and relevant ions in cells and living organisms. Also, the fundamental principles associated with the design of ratiometric fluorescent probes and perspectives about how to expand their biological applications are discussed.


Assuntos
Cobre/análise , Corantes Fluorescentes/química , Zinco/análise , Corantes Fluorescentes/síntese química , Humanos , Íons/análise , Estrutura Molecular
3.
Food Chem ; 302: 125342, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31416002

RESUMO

Cereal crops are the rich source of nutritional components that play an important role in micronutrient malnutrition. Biofortification is one of the most successful approaches to enhance the level of micronutrients, mainly targeted in bread wheat. Bread wheat is one of main sources of calories and proteins in the developing countries. In the present study, 50 bread wheat genotypes characterized for the zinc and iron content, the most important micronutrients. On the basis of the results, the nineteen genotypes were selected and evaluated for biochemical as well as quality parameters. The protein content, gluten quantity and quality found to be reduced in high zinc containing genotypes, whereas the total soluble sugars, total carotenoids, proline and grain hardness found to be in positive relation with high micronutrient content. These results could be useful to generate bread wheat varieties rich in micronutrients as well as better nutritional and quality traits.


Assuntos
Biofortificação , Pão , Micronutrientes/metabolismo , Triticum/química , Triticum/genética , Carotenoides/análise , Qualidade dos Alimentos , Genótipo , Ferro/análise , Ferro/metabolismo , Micronutrientes/genética , Prolina/análise , Prolina/metabolismo , Sementes/química , Açúcares/análise , Zinco/análise , Zinco/metabolismo
4.
Chemosphere ; 240: 124922, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31563718

RESUMO

This study examined the effects of soil heavy metals, macronutrients, texture and pH as well as plant species richness and composition on soil respiration, enzymatic activity, microbial biomass, metabolic quotient (qCO2) and arbuscular mycorrhizal fungi (AMF) at sites of historical Zn-Pb mining. The study was conducted both on a large scale (65 heaps scattered over the area of 750 km2) and on a small scale (25 plots along two 48 m transects extending from heaps to adjacent fallow fields). Total concentrations of metals exceeded 400 (Cd), 20,000 (Pb) and 80,000 (Zn) mg kg-1 at the most polluted sites. Although they decreased along the heap-fallow direction, they still remained above environmental standards in fallow soils. In contrast, some soluble metal forms increased with the increasing distance from heaps. Soil organic matter had the strongest positive effect on most microbial parameters. Total and/or available heavy metals exhibited significant negative effects on microbial biomass, enzymatic activity and AMF, and a positive effect on qCO2. Organic matter alleviated negative effects of heavy metals on microorganisms; they were not observed where the increase in the contamination was accompanied by the increase in organic matter content. Plant species richness affected positively enzymatic activity and mycorrhization level. Plant species composition possibly contributed to the formation of soil microbial communities, but its effect was entangled in that of heavy metals as plant communities changed along pollution gradients (from metal-tolerant grasslands dominated by Festuca ovina to calcareous grasslands and ruderal communities at less polluted sites).


Assuntos
Poluição Ambiental/análise , Festuca/microbiologia , Metais Pesados/análise , Poluentes do Solo/análise , Solo/química , Biomassa , Cádmio/análise , Festuca/química , Substâncias Húmicas/análise , Chumbo/análise , Microbiota , Mineração , Micorrizas/crescimento & desenvolvimento , Microbiologia do Solo , Zinco/análise
5.
Food Chem ; 308: 125655, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31669947

RESUMO

Mechanisms of degradation and absorption of mineral complexes by the human digestive system are complex and still under investigation. The elaborate matrix of vegetables, and the presence of phytates and other inhibitors make study of these mechanisms difficult. In this qualitative study, extracts from freeze-dried savoy cabbage, broccoli, kale and spinach were subjected to digestion in vitro at pH 2.0 and pH 7.5 and analysed using SEC-ICP-MS. The results suggest that low molecular weight species (peak 6), related to the iron and zinc fractions, which appeared after acidic digestion in all vegetables, except in kale, were considerably reduced after digestion at pH 7.5. Low molecular weight species (peak 9), related to the phosphorus fraction, were present in all vegetables, except in kale, after alkaline digestion. While cabbage, broccoli and spinach showed similar degradation patterns, kale showed a different degradation behaviour.


Assuntos
Brassicaceae/química , Ferro/análise , Spinacia oleracea/química , Verduras/química , Zinco/análise
6.
Food Chem ; 308: 125652, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31669949

RESUMO

Vegetables contain iron, zinc and phosphorus as complexes with phytates limiting their availability from a vegetarian diet, meaning non-haem iron deficiency anaemia and zinc deficiency immune malfunction are a risk. Although these elements have been analysed previously in biological fluids and cereal using LC-ICP-MS, there is no method suitable for analysing iron, zinc and phosphorus simultaneously in vegetables because of their complex matrix. In this study, we analysed iron, zinc and phosphorus in cabbage, broccoli, pepper, spinach, kale and rocket after a simulated gastrointestinal digestion using a newly optimised SEC-ICP-MS method. Ammonium nitrate, as the mobile phase, and a suitable rinsing regime, allowed good reproducibility and maintenance of the equipment. The method showed good reproducibility and can be easily adapted to other vegetables, as required.


Assuntos
Brassicaceae/química , Ferro/análise , Fósforo/análise , Verduras/química , Zinco/análise , Espectrometria de Massas , Reprodutibilidade dos Testes
7.
Chemosphere ; 240: 124938, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31574444

RESUMO

Clearwater Mesa (James Ross Island, northeast Antarctic Peninsula) provides a unique opportunity to study solute dynamics and geochemical weathering in the pristine lacustrine systems of a high latitude environment. In order to determine major controls on the solute composition of these habitats, a geochemical survey was conducted on 35 lakes. Differences between lakes were observed based on measured physico-chemical parameters, revealing neutral to alkaline waters with total dissolved solids (TDS) < 2500 mg L-1. Katerina and Trinidad-Tatana systems showed an increase in their respective TDS, total organic carbon values, and finner sediments from external to internal lakes, indicating an accumulation of solutes due to weathering. Norma and Florencia systems exhibited the most diluted and circumneutral waters, likely from the influence of glacier and snow melt. Finally, isolated lakes presented large variability in TDS values, indicating weathering and meltwater contributions at different proportions. Trace metal abundances revealed a volcanic mineral weathering source, except for Pb and Zn, which could potentially indicate atmospheric inputs. Geochemical modelling was also conducted on a subset of connected lakes to gain greater insight into processes determining solute composition, resulting in the weathering of salts, carbonates and silicates with the corresponding generation of clays. We found CO2 consumption accounted for 20-30% of the total species involved in weathering reactions. These observations allow insights into naturally occurring geochemical processes in a pristine environment, while also providing baseline data for future research assessing the impacts of anthropogenic pollution and the effects of climate change.


Assuntos
Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Lagos/química , Minerais/análise , Compostos Orgânicos/análise , Oligoelementos/análise , Regiões Antárticas , Carbonatos/análise , Mudança Climática , Ecossistema , Camada de Gelo/química , Chumbo/análise , Trinidad e Tobago , Tempo (Meteorologia) , Zinco/análise
8.
Chemosphere ; 239: 124767, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31518925

RESUMO

The present study analyzed the Peruvian scallop Argopecten purpuratus and its food sources for metal and fatty acid concentrations in order to determine spatial and temporal differences. Metals such as copper (Cu), manganese (Mn), and zinc (Zn) in gills and iron (Fe) and Zn in sediments were the most significant explaining factors for spatial differentiations (degree of contamination), while for fatty acids, it was C14:0, C15:0, C16:0 and C18:0 in A. purpuratus' muscle and in its food sources, which explained more temporal differences (El Niño-Southern Oscillation (ENSO) effect). Gills, digestive gland and intestine were the tissues where metal accumulation was the highest in A. purpuratus. Cd in digestive gland was always high, up to ∼250-fold higher than in other tissues, as previously reported in other bioindicator species for metal pollution. Fatty acids were good biomarkers when annual comparisons were performed, while metals when locations were compared. ENSO 2017 played an important role to disentangle A. purpuratus' biological conditions and food sources. A. purpuratus from Paracas locations mostly showed higher metal concentrations in gills and digestive glands, and lower fatty acid concentrations in muscle than those from Sechura and Illescas Reserved Zone.


Assuntos
Monitoramento Ambiental/métodos , Sedimentos Geológicos/análise , Pectinidae/química , Poluentes Químicos da Água/análise , Animais , Aquicultura , Cobre/análise , Cobre/farmacocinética , Biomarcadores Ambientais , Ácidos Graxos/análise , Brânquias/química , Ferro/análise , Ferro/farmacocinética , Manganês/análise , Manganês/farmacocinética , Músculos/química , Pectinidae/metabolismo , Peru , Frutos do Mar/análise , Análise Espaço-Temporal , Distribuição Tecidual , Zinco/análise , Zinco/farmacocinética
9.
Chemosphere ; 239: 124660, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31505445

RESUMO

The co-precipitation of Fe2+, Cu2+, Zn2+, Cd2+ and Ni2+ were investigated by a mechanochemical processing with CaCO3. The results showed that the synergies of the metal ions led to efficient co-precipitation. The precipitation of Fe2+, Cu2+ and Cd2+ are over 99% and that of Zn2+ and Ni2+ about 98.4% and 93.8%. A significant advantage of the process is that the moisture content of filter residue is much lower (less than 50%) than that using the lime neutralization (more than 80%), offering a potential solution to the sludge problem in wastewater treatment. A further advantage is the neutral pH (about 7.5) obtained by using CaCO3 rather than the highly alkaline pH (about 11) obtained using lime (Ca(OH)2) neutralization method.


Assuntos
Precipitação Fracionada/métodos , Metais Pesados/análise , Esgotos/química , Purificação da Água/métodos , Cádmio/análise , Carbonato de Cálcio/química , Cobre/análise , Dessecação/métodos , Concentração de Íons de Hidrogênio , Ferro/análise , Níquel/análise , Zinco/análise
10.
Chemosphere ; 239: 124720, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31499313

RESUMO

Cathodic protection by galvanic anodes (GACP) is often used to protect immerged metallic structures in harbor environments, especially GACP employing aluminum-based anodes. To follow a previous study that was performed in a laboratory on Al-anode, two monitoring periods were performed in parallel, one in an in situ environment (in the Port of Calais) for 42 months and the other in a laboratory for 18 months, to evaluate the transfer of metals constituting the Al-anode towards the sedimentary compartment. During each monitoring, two conditions of agitation of water (weak and strong) were compared, and different factors of sediment quality were used to assess the enrichment and potential toxic effects of these released metals. The results showed that the dissolution of Al-anode-induced a greater Zn enrichment of sediment than an Al enrichment. This is in contrast with the abundance of these elements present in the composition of the anode and suggested a potential toxic effect for marine organisms with regards to the discovered Zn level, especially in confined areas.


Assuntos
Alumínio , Eletrodos/efeitos adversos , Monitoramento Ambiental/métodos , Sedimentos Geológicos/análise , Organismos Aquáticos , Sedimentos Geológicos/química , Metais Pesados/análise , Poluentes Químicos da Água/análise , Zinco/análise , Zinco/toxicidade
11.
Spectrochim Acta A Mol Biomol Spectrosc ; 224: 117389, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31377683

RESUMO

Rational design chelating fluorescent sensors probing metal ions in biological system are continuously hot essays nowadays, especially for zinc detection. Herein, a naphthylideneimine based zinc fluorescence probe (3) was prepared and characterized in this work. Structural features and optical properties of 3 and its metallic complexes were characterized. Fluorescent experiment indicates 3 is extremely sensitive and selective for Zn2+ with a strong fluorescence enhancement (∼34 folds) in aqueous buffer solution with a limit of detection (LOD) of 3.78 × 10-7 mol L-1. Formation constant (logKa) of the chelating complex of 3 and Zn2+ ion was determined to be 4.45. Theoretical studies were carried out to get deep insight into the response mechanism in the sensing process. Density functional theory (DFT) methods calculated formation Gibbs free energy (ΔrGmÓ©) of the deprotonated complexes model (32- ⊃ Zn) is -2.9 kcal/mol, which is in good agreement with the experimental result. The calculation results show that the low excitation states can be ascribe to S0 → T2 and S0 → S1 at 390-430 nm and 310-330 nm, respectively, due to the π → π∗ transition. Finally, yeast cell imaging experiments indicate that 3 can monitor intracellular Zn2+ as well. These findings would enable this fluorescent probe to be used as a Zinc sensor.


Assuntos
Corantes Fluorescentes/química , Naftalenos/química , Bases de Schiff/química , Espectrometria de Fluorescência/métodos , Zinco/análise , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes , Saccharomyces cerevisiae/química
12.
Environ Sci Pollut Res Int ; 26(34): 35107-35120, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31679142

RESUMO

In freshwater ecosystem, phototrophic biofilms play a crucial role through adsorption and sequestration of organic and inorganic pollutants. However, extracellular polymeric substance (EPS) secretion by phototrophic biofilms exposed to metals is poorly documented. This work evaluated the physiological responses of phototrophic biofilms by exposing three microorganisms (cyanobacterium Phormidium autumnale, diatom Nitzschia palea and green alga Uronema confervicolum) to 20 and 200 µg L-1 of Cu or 60 and 600 µg L-1 of Zn, both individually and in combination. Analysis of metal effects on algal biomass and photosynthetic efficiency showed that metals were toxic at higher concentrations for these two parameters together and that all the strains were more sensitive to Cu than to Zn. U. confervicolum was the most impacted in terms of growth, while P. autumnale was the most impacted in terms of photosynthetic efficiency. In consequence to metal exposure at higher concentrations (Cu200, Zn600 and Cu200Zn600), a higher EPS production was measured in diatom and cyanobacterium biofilms, essentially caused by an overproduction of protein-like polymers. On the other hand, the amount of secreted polysaccharides decreased during metal exposure of the diatom and green alga biofilms. Size exclusion chromatography revealed specific EPS molecular fingerprints in P. autumnale and N. palea biofilms that have secreted different protein-like polymers during their development in the presence of Zn600. These proteins were not detected in the presence of Cu200 despite an increase of proteins in the EPS extracts compared to the control. These results highlight interesting divergent responses between the three mono-species biofilms and suggest that increasing protein production in EPS biofilms may be a fingerprint of natural biofilm against metal pollutants in freshwater rivers.


Assuntos
Biofilmes/crescimento & desenvolvimento , Cobre/toxicidade , Zinco/toxicidade , Biofilmes/efeitos dos fármacos , Biomassa , Cobre/análise , Cianobactérias/metabolismo , Diatomáceas/metabolismo , Ecossistema , Matriz Extracelular de Substâncias Poliméricas , Água Doce , Metais/análise , Fotossíntese , Rios , Zinco/análise
13.
Environ Monit Assess ; 191(12): 734, 2019 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-31707592

RESUMO

The quality of drinking water source remains as a major concern in areas of developing and underdeveloped countries worldwide. The treatment and supply of drinking water in Rwanda are carried out by Water and Sanitation Corporation, a state-owned public company. However, it is not able to supply water to all households. Consequently, the non-serviced households depend on natural water sources, like springs, to meet their water requirements. Nevertheless, the water quality in these springs is scarcely known. Therefore, this study assessed and compared metal elements in drinking water sources in the dry and rainy seasons in 2017 using the contamination degree, metal index, and geographic information systems to reveal the spatial distribution of water quality within the considered water sources of springs in Rwanda. The samples were collected monthly from nine water sources of springs and the measured elements are aluminium, calcium, copper, iron, manganese, and zinc. The metal index indicated that during the dry season and rainy season, the sites of Kibungo (1.10 and 1.26) and Kinigi (1.01 and 1.54) have assessed a metal index which is higher than 1. Thus, the water quality of those sites was getting the threshold of warning. The analysis indicated that pollutants are easily transported into water bodies during the rainy season in urban and rural areas to a greater extent than during the dry season .


Assuntos
Água Potável/análise , Monitoramento Ambiental , Sistemas de Informação Geográfica , Poluentes Químicos da Água/análise , Abastecimento de Água/estatística & dados numéricos , Cádmio/análise , Cobre/análise , Ferro/análise , Metais/análise , Compostos Orgânicos/análise , Chuva , Ruanda , Estações do Ano , Poluentes Químicos da Água/normas , Qualidade da Água , Zinco/análise
14.
Environ Monit Assess ; 191(12): 742, 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31713691

RESUMO

In the 3-year study, heavy metals mobility factors for soils of public playgrounds within Owerri metropolis were correlated with soil particle size. Such studies could develop a body of knowledge that could enable detection and quantification of potential risk of metals to children from playground soil without actually involving children. Calculated values of mobility factors were subjected statistical treatment and to obtain descriptive statistics. Regression analysis of mobility factors and particle size were determined. Copper and zinc were most mobile elements, while cobalt was least mobile. Result showed that clay particle size had strong influence on mobility factors. The significance of this study is that recent estimation of mobility factors of metals are used to expand its possible understanding and application to fundamental and practical problems of ecotoxicology of metals which could reflect metals potentials to cause harm thereby permitting the evaluation of metals toxicity without direct involvement of children.


Assuntos
Monitoramento Ambiental , Metais Pesados/análise , Parques Recreativos , Poluentes do Solo/análise , Criança , Cobre/análise , Humanos , Tamanho da Partícula , Solo , Zinco/análise
15.
Water Sci Technol ; 80(3): 448-457, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31596256

RESUMO

In the present study, continuous-flow column experiments (using glass column, Tygon tubing, and peristaltic pump Manostat Carter) were conducted to investigate the performance of permeable sorption barriers for the removal of cadmium and zinc from synthetic groundwater. Zeolite, ion-exchange resin and granular activated carbon as reactive materials were used. The effectiveness and stability of reactive materials were studied by monitoring of changes of metal ions concentration and selected background anions and cations concentration in groundwater during its flow through columns. Results showed that ion exchange resin was the most effective material of permeable reactive barrier (PRB). Performance of resin barrier remained effective (>99.5% metal ions removal) for the time corresponding to on average of about 10,000 min. The high efficiency of ion-exchange resin in PRB for removal of heavy metals from groundwater was coupled with its reactivity and long barrier lifetime. The breakthroughs in the column tests on activated carbon and zeolite using synthetic groundwater occurred much earlier as compared to resin. Therefore, the system using resin requires smaller amount to treat a given volume of groundwater as compared to other materials. Moreover, the presence of other ions did not impact on activity and permeability of barrier filled with resin.


Assuntos
Cádmio/análise , Água Subterrânea/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Zinco/análise , Íons
16.
J Agric Food Chem ; 67(44): 12172-12181, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31609615

RESUMO

Understanding the mechanisms of absorption and transport of foliar nutrition is a key step towards the development of advanced fertilization methods. This study employed X-ray fluorescence (XRF) and X-ray absorption near edge spectroscopy (XANES) to trace the in vivo absorption and transport of ZnO and ZnSO4(aq) to soybean leaves (Glycine max). XRF maps monitored over 48 h showed a shape change of the dried ZnSO4(aq) droplet, indicating Zn2+ absorption. Conversely, these maps did not show short movement of Zn from ZnO. XRF measurements on petioles of leaves that received Zn2+ treatments clarified that the Zn absorption and transport in the form of ZnSO4(aq) was faster that of ZnO. Solubility was the major factor driving ZnSO4(aq) absorption. XANES speciation showed that in planta Zn is transported coordinated with organic acids. Because plants demand Zn during their entire lifecycle, the utilization of sources with different solubilities can increase Zn use efficiency.


Assuntos
Soja/metabolismo , Espectrometria de Fluorescência/métodos , Espectroscopia por Absorção de Raios X/métodos , Zinco/análise , Zinco/metabolismo , Transporte Biológico , Fertilizantes/análise , Folhas de Planta/química , Folhas de Planta/metabolismo , Soja/química
17.
Environ Monit Assess ; 191(11): 680, 2019 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-31655911

RESUMO

The objective of the study was to establish the effect of component share in mixtures and harvest date on concentrations of selected heavy metals in the green fodder of field pea, oat, and their mixtures. The research hypothesis assumed that the cultivation of peas and oats in pure sowing, and in mixtures will also allow to choose combinations from which the forage will have the lowest content of heavy metals. Field research was conducted at the Zawady Experimental Farm (52° 03' 39″ N, 22° 33' 80″ E) which belongs to Siedlce University of Natural Sciences and Humanities. Two factors were tested in the study: I-component share in the mixture: field pea-pure stand 100%, oat-pure stand 100%, field pea 75% + oat 25%, field pea 50% + oat 50%, field pea 25% + oat 75%; II-harvest date: field pea flowering stage, field pea flat pod stage. Plant material was sampled to determine the following elements: Cu, Zn, Cd, Pb, Cr, and Ni. The results of the study demonstrated that field pea grown in pure stand had the highest copper and zinc contents, and the lowest chromium and nickel contents. Field pea mixed with oat significantly reduced heavy metal content in green fodder. Cadmium and lead contents in the green fodder of field pea/oat mixtures were too low to be determined by means of the spectrometer Perkin Elmer Optima 8300. Regular checks of heavy metal contents are recommended in spite of their low amounts in the green fodder of field pea/oat mixtures.


Assuntos
Ração Animal/análise , Monitoramento Ambiental , Metais Pesados/análise , Poluentes do Solo/análise , Animais , Avena , Cádmio/análise , Bovinos , Cromo/análise , Cobre/análise , Grão Comestível/química , Níquel/análise , Ervilhas , Zinco/análise
18.
Nature ; 574(7776): 95-98, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31554969

RESUMO

Micronutrient deficiencies account for an estimated one million premature deaths annually, and for some nations can reduce gross domestic product1,2 by up to 11%, highlighting the need for food policies that focus on improving nutrition rather than simply increasing the volume of food produced3. People gain nutrients from a varied diet, although fish-which are a rich source of bioavailable micronutrients that are essential to human health4-are often overlooked. A lack of understanding of the nutrient composition of most fish5 and how nutrient yields vary among fisheries has hindered the policy shifts that are needed to effectively harness the potential of fisheries for food and nutrition security6. Here, using the concentration of 7 nutrients in more than 350 species of marine fish, we estimate how environmental and ecological traits predict nutrient content of marine finfish species. We use this predictive model to quantify the global spatial patterns of the concentrations of nutrients in marine fisheries and compare nutrient yields to the prevalence of micronutrient deficiencies in human populations. We find that species from tropical thermal regimes contain higher concentrations of calcium, iron and zinc; smaller species contain higher concentrations of calcium, iron and omega-3 fatty acids; and species from cold thermal regimes or those with a pelagic feeding pathway contain higher concentrations of omega-3 fatty acids. There is no relationship between nutrient concentrations and total fishery yield, highlighting that the nutrient quality of a fishery is determined by the species composition. For a number of countries in which nutrient intakes are inadequate, nutrients available in marine finfish catches exceed the dietary requirements for populations that live within 100 km of the coast, and a fraction of current landings could be particularly impactful for children under 5 years of age. Our analyses suggest that fish-based food strategies have the potential to substantially contribute to global food and nutrition security.


Assuntos
Pesqueiros , Peixes/metabolismo , Abastecimento de Alimentos , Internacionalidade , Micronutrientes/deficiência , Micronutrientes/metabolismo , Estado Nutricional , Animais , Teorema de Bayes , Cálcio/análise , Pré-Escolar , Proteínas na Dieta/análise , Ácidos Graxos Ômega-3/análise , Produtos Pesqueiros/análise , Produtos Pesqueiros/economia , Pesqueiros/economia , Peixes/classificação , Humanos , Lactente , Ferro/análise , Micronutrientes/análise , Selênio/análise , Vitamina A/análise , Zinco/análise
19.
J Photochem Photobiol B ; 199: 111602, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31505421

RESUMO

A simple imine based receptor NA-1 has been synthesized for detection of Zinc ions. Probe NA-1 showed the selective colorimetric changes with Zinc (II) ions whereas other metal ions didn't showed any observable colorimetric changes. The probe showed the very selective turn-on fluorescence response with Zn(II) ions among other rival metal ions like Cd(II) and Hg(II). The mode of binding was studied by 1H-nmr titrations and fluorescence spectroscopy. Jobs plot analysis confirming that the probe NA-1 forms 1:1 complex with Zn(II). The observed fluorescence and absorption change further supported by theoretical calculations. The turn-on fluorescence of the probe NA-1 is probably attributable to the interruption of intramolecular charge transfer as well as ESIPT. The limit of detection of the probe for Zn(II) sensing is in the range of 14 nano molar. Cytotoxicity (MTT) assay of the probe in live HeLa cells is showing that the probe is least toxic to cells. The probe NA-1 is effectively applied to detect Zn(II) ions in HeLa cells and suggesting the probe is NA-l permeable to cell wall and viable for Zinc(II) ions imaging in live cells.


Assuntos
Ampirona/química , Corantes Fluorescentes/química , Imagem Óptica/métodos , Zinco/análise , Técnicas Biossensoriais/métodos , Cádmio/análise , Cátions Bivalentes/análise , Sobrevivência Celular/efeitos dos fármacos , Células HeLa , Humanos , Mercúrio/análise , Estrutura Molecular , Sensibilidade e Especificidade , Relação Estrutura-Atividade
20.
J Food Sci ; 84(10): 2840-2846, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31517998

RESUMO

Cu, Fe, Mn, Mo, Selenium (Se), and Zn bioavailability from selenate- and selenite-enriched lettuce plants was studied by in vitro gastrointestinal digestion followed by an assay with Caco-2 cells. The plants were cultivated in the absence and presence of two concentrations (25 and 40 µmol/L of Se). After 28 days of cultivation, the plants were harvested, dried, and evaluated regarding the total concentration, bioaccessibility, and bioavailability of the analytes. The results showed that biofortification with selenate leads to higher Se absorption by the plant than biofortification with selenite. For the other nutrients, Mo showed high accumulation in the plants of selenate assays, and the presence of any Se species led to a reduction of the plant uptake of Cu and Fe. The accumulation of Zn and Mn was not strongly influenced by the presence of any Se species. The bioaccessibility values were approximately 71%, 10%, 52%, 84%, 71%, and 86% for Cu, Fe, Mn, Mo, Se, and Zn, respectively, and the contribution of the biofortified lettuce to the ingestion of these minerals is very small (except for Se and Mo). Due to the low concentrations of elements from digested plants, it was not possible to estimate the bioavailability for some elements, and for Mo and Zn, the values are below 6.9% and 3.4% of the total concentration, respectively. For Se, the bioavailability was greater for selenite-enriched than selenate-enriched plants (22% and 6.0%, respectively), because selenite is biotransformed by the plant to organic forms that are better assimilated by the cells.


Assuntos
Cobre/análise , Ferro/análise , Alface/química , Manganês/análise , Molibdênio/análise , Selênio/análise , Zinco/análise , Biofortificação , Disponibilidade Biológica , Células CACO-2 , Cobre/metabolismo , Humanos , Ferro/metabolismo , Alface/metabolismo , Manganês/metabolismo , Molibdênio/metabolismo , Ácido Selênico/análise , Ácido Selênico/metabolismo , Ácido Selenioso/análise , Ácido Selenioso/metabolismo , Selênio/metabolismo , Zinco/metabolismo
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