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1.
Molecules ; 26(4)2021 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-33669948

RESUMO

To demonstrate the importance of sample preparation used in Fourier transform infrared (FTIR) spectroscopy of microbiological materials, bacterial biomass samples with and without grinding and after different drying periods (1.5-23 h at 45 °C), as well as biogenic selenium nanoparticles (SeNPs; without washing and after one to three washing steps) were comparatively studied by transmission FTIR spectroscopy. For preparing bacterial biomass samples, Azospirillum brasilense Sp7 and A. baldaniorum Sp245 (earlier known as A. brasilense Sp245) were used. The SeNPs were obtained using A. brasilense Sp7 incubated with selenite. Grinding of the biomass samples was shown to result in slight downshifting of the bands related to cellular poly-3-hydroxybutyrate (PHB) present in the samples in small amounts (under ~10%), reflecting its partial crystallisation. Drying for 23 h was shown to give more reproducible FTIR spectra of bacterial samples. SeNPs were shown to contain capping layers of proteins, polysaccharides and lipids. The as-prepared SeNPs contained significant amounts of carboxylated components in their bioorganic capping, which appeared to be weakly bound and were largely removed after washing. Spectroscopic characteristics and changes induced by various sample preparation steps are discussed with regard to optimising sample treatment procedures for FTIR spectroscopic analyses of microbiological specimens.


Assuntos
Azospirillum/química , Nanopartículas/análise , Selênio/análise , Biomassa , Espectroscopia de Infravermelho com Transformada de Fourier
2.
Mar Pollut Bull ; 164: 112102, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33561583

RESUMO

The purpose of this work was to use the deep-water chimaera Hydrolagus colliei to examine the bioaccumulation and availability of Hg and Se in its deep-water habitat; the Se:Hg molar ratio was calculated to establish baseline information of the species and its associated ecosystem. The organisms were collected from northern Gulf of California. Hg levels in muscle were higher than liver and the opposite pattern happened with Se concentrations. Female had total lengths and weights higher than male but there were not found differences between elements concentrations by sex. Hg in muscle was correlated with weight. Molar Se:Hg ratio in muscle was the lowest compared to the liver. It was hypothesized that Hg and Se uptake to H. colliei were by its feeding habits because is a dominant species component of the demersal ecosystem and that play and important functional role in the control of oceanic ecosystem structure and function.


Assuntos
Mercúrio , Selênio , Poluentes Químicos da Água , Animais , California , Ecossistema , Monitoramento Ambiental , Feminino , Masculino , Mercúrio/análise , Oceanos e Mares , Selênio/análise , Poluentes Químicos da Água/análise
3.
Environ Sci Pollut Res Int ; 28(15): 18392-18406, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33471308

RESUMO

The mutual mitigation of selenium and mercury toxicity is particularly interesting, especially for humans. Mercury is widely recognized as a pantoxic element; all forms are toxic to all organisms. Less well known is that selenium in excess is toxic as well. The high affinity between these elements influences their bioavailability and toxicity. In this paper, we use selected species from Barnegat and Delaware Bays in New Jersey to examine variations in levels of selenium and mercury, and selenium:mercury molar ratios between and within species. We report on species ranging from horseshoe crab eggs (Limulus polyphemus), a keystone species of the food chain, to several fish species, to fish-eating birds. Sampling began in the 1970s for some species and in the 1990s for others. We found no clear time trends in mercury levels in horseshoe crab eggs, but selenium levels declined at first, then remained steady after the mid1990s. Concentrations of mercury and selenium in blood of migrant shorebirds directly reflected levels in horseshoe crab eggs (their food at stopover). Levels of mercury in eggs of common terns (Sterna hirundo) varied over time, and may have declined slightly since the mid2000s; selenium levels also varied temporally, and declined somewhat. There were variations in mercury and selenium levels in commercial, recreational, and subsistence fish as a function of species, season, and size (a surrogate for age). Selenium:mercury molar ratios also varied as a function of species, year, season, and size in fish. While mercury levels increased with size within individual fish species, selenium levels remained the same or declined. Thus selenium:mercury molar ratios declined with size in fish, reducing the potential of selenium to ameliorate mercury toxicity in consumers. Mercury levels in fish examined were higher in early summer and late fall, and lower in the summer, while selenium stayed relatively similar; thus selenium:mercury molar ratios were lower in early summer and late fall than in midsummer. We discuss the importance of temporal trends in biomonitoring projects, variations in levels of mercury, selenium, and the molar ratios as a function of several variables, and the influence of these on risks to predators and humans eating the fish, and the eggs of gulls, terns. Our data suggests that variability limits the utility of the selenium:mercury molar ratio for fish consumption advisories and for risk management.


Assuntos
Mercúrio , Selênio , Poluentes Químicos da Água , Animais , Monitoramento Biológico , Biota , Monitoramento Ambiental , Estuários , Peixes , Humanos , Mercúrio/análise , New Jersey , Selênio/análise , Poluentes Químicos da Água/análise
4.
Food Chem ; 348: 129150, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-33513529

RESUMO

Selenium-enriched potato is a good supplement for selenium-deficient populations. This study evaluated the influence of two most common cooking methods, including boiling and frying, on selenium content, speciation, and in vitro bioaccessibility of selenium-biofortified potato tubers. After foliar application of 200 µg/mL sodium selenite, potato tubers with 1.33 µg Se/g were obtained. Peeling resulted in 53.4%-69.9% loss of selenium in tubers. The total selenium content decreased by approximately 43.3% after boiling, among which up to 38.5% of the lost selenium is found in the boiling water. Nearly 31.7% of selenium was lost via volatilization during frying. Both cooking methods significantly enhanced the bioaccessibility of Se(IV) in tubers. Whereas SeMeCys became less bioaccessible after boiling. SeMet and SeCys2 in fired tubers were not accessible after digestion. This study suggested that boiling is more appropriate for cooking selenium-enriched potatoes.


Assuntos
Culinária/métodos , Selênio/análise , Solanum tuberosum/química , Digestão , Tubérculos/química , Tubérculos/metabolismo , Selênio/metabolismo , Selenito de Sódio/química , Selenito de Sódio/metabolismo , Solanum tuberosum/metabolismo , Espectrofotometria Atômica
5.
Bull Environ Contam Toxicol ; 106(1): 40-43, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33452893

RESUMO

In this study, we investigated the distribution and chemical speciation of Se in Se-rich soil by using micro-focused X-ray absorption near-edge structure (µ-XANES) spectroscopy coupling with X-ray fluorescence (µ-XRF) mapping. The microscale distribution showed that Se is heterogeneously distributed in the soil from seleniferous areas in Enshi, China. Se K-edge µ-XANES analysis suggested that Se is mainly present as Se(IV), organic Se(-II) or Se(0) species in Se-rich agricultural soil. The findings from this study would help improve the understanding of the fate, mobility, bioavailability, and biogeochemical cycling of Se in the seleniferous soil environment.


Assuntos
Selênio , Poluentes do Solo , China , Selênio/análise , Solo , Poluentes do Solo/análise , Espectroscopia por Absorção de Raios X
6.
Sci Total Environ ; 766: 144247, 2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33421779

RESUMO

White-winged scoters (Melanitta fusca; WWSC) and surf scoters (M. perspicillata; SUSC) have declined by over 60% in recent decades. Identifying contributing factors from within a mosaic of sublethal, multiple stressors is challenging. In urbanized Puget Sound, Washington, USA where scoters winter, changes in prey availability explained only a portion of local declines, suggesting that other "silent stressors" such as sublethal contaminants might play a role. Past studies of pollutant effects on scoters used Fisherian statistics that often revealed few correlates; however, novel statistical approaches could detect and provide more insights about sublethal impacts. Our objectives were to (1) relate pollutant accumulation to health of the birds, and (2) compare permutational multivariate statistics with traditional approaches in identifying sublethal health effects. We collected scoters from three locations in Puget Sound in December 2005 and March 2006, and measured cadmium (Cd), mercury (Hg), and selenium (Se) levels in livers and kidneys. To assess impacts of low contaminants levels in tissues on nutritional status (whole-body mass, lipid, and protein; and triglycerides, ß-hydroxybutyrate, and uric acid in blood), we compared statistical methods. Permutational multivariate methods use Monte Carlo techniques to assess how an integrated matrix of physiological responses in each animal respond to contaminants. Univariate regressions revealed very few and inconsistent relationships. In contrast, multivariate models showed that liver Hg and Se explained 25% of the variance in nutritional status of white-winged scoters; and in surf scoters, Cd, Hg, and Se in tissues explained 14 to 27% of nutritional status depending on site. The influence of these factors equals other aspects of habitat such as foraging conditions. Our study indicates that permutational multivariate statistics can be a powerful tool for identifying sublethal contaminant associations that, with non-contaminant stressors, can influence nutritional status and thus, contribute to population dynamics.


Assuntos
Poluentes Ambientais , Selênio , Oligoelementos , Animais , Patos , Poluentes Ambientais/análise , Poluentes Ambientais/toxicidade , Estado Nutricional , Selênio/análise , Selênio/toxicidade , Washington
7.
Sci Total Environ ; 770: 144664, 2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-33513517

RESUMO

Selenium (Se) content of crops depends on the local soil Se content and/or its bioavailability, and identifying the influence factors of soil Se bioavailability is a significant basis for adopting targeted agronomic measures to improve the Se nutritional status of humans. In this study, the main wheat-producing region in Shaanxi province with similar parent material and climate conditions was selected as the study area. The total Se contents of 602 soil samples and their corresponding wheat grains were determined, and the distribution characteristics of soil Se bioavailability and its dominant influential factors were investigated. Results showed that the total Se content ranged from 0.02 mg/kg to 1.67 mg/kg (average of 0.25 ± 0.25 mg/kg) in soil, which was lower than that content in China (0.29 mg/kg). The Se content of wheat grain was 0.001-1.50 mg/kg (average of 0.11 ± 0.19 mg/kg). The distribution trend of the Se content in wheat grains was different from that of the total soil Se, but it was consistent with the distribution of soil bioavailable Se content. The bioavailable Se accounted for 11.1% of the total soil Se. This could be attributed to relatively high soil Se bioavailability of the study area belonging to alkaline soil (with a pH of approximately 8). Both redundancy analysis and path analysis revealed that soil pH and organic matter were the dominant influential factors of soil Se bioavailability in Shaanxi wheat-producing area, and the soil Se bioavailability increased with these two parameters raising. On this basis, a prediction model was established to predict the Se content in wheat grain. The results show that the various agronomic measures could be used to produce Se-enriched wheat by regulating the soil pH and the organic matter content in Se biofortification practice.


Assuntos
Selênio , Solo , Disponibilidade Biológica , China , Humanos , Selênio/análise , Triticum
8.
Chemosphere ; 263: 128286, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33297230

RESUMO

An unusual mortality event (UME) attributed to morbillivirus infection was identified in two Guiana dolphin populations from the Southeastern Brazilian coast. The aim of this study was to characterize total mercury (THg), methylmercury (MeHg) and selenium (Se) bioaccumulation and body burden in Guiana dolphins from Sepetiba Bay (RJ) collected before (n = 61) and during the UME (n = 20). Significantly lower Se concentrations were found in the livers of individuals collected during the UME (Mann-Whitney test; p = 0.03), probably due to impairment of the detoxification process in the liver. There were differences in THg and Se concentrations in the organs and tissues of individuals (Kruskal-Wallis test, p < 0.05), but not MeHg (Kruskal-Wallis test, p = 0.07). For THg, the liver showed the higher concentrations and differed among organs and tissues analyzed such as blubber (Tukey's test for unequal N; p = 0.003). For Se concentrations, the skin and kidney presented the higher concentrations and varied among other tissues/organs, like muscle (Tukey's test for unequal N; p = 0.02). Differences in body burdens were observed among specimens collected previously and during the UME probably due to the remobilization and transport of the muscle-stored MeHg to other tissues/organs. This abrupt input of MeHg into the bloodstream may cause serious health damage. Indeed, evidences of methylmercury intoxication was observed in Guiana dolphins in Sepetiba Bay. In conclusion, bioaccumulation patterns, the detoxification process and body burden were affected by morbillivirus.


Assuntos
Golfinhos , Mercúrio , Compostos de Metilmercúrio , Morbillivirus , Selênio , Poluentes Químicos da Água , Animais , Carga Corporal (Radioterapia) , Brasil , Monitoramento Ambiental , Humanos , Mercúrio/análise , Compostos de Metilmercúrio/análise , Compostos de Metilmercúrio/toxicidade , Selênio/análise , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
9.
Sci Total Environ ; 762: 144103, 2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33360462

RESUMO

In agricultural lands with selenium (Se) deficiency, bioavailability of Se in plants is low. Residents from large-scale agricultural production areas with Se deficiency often suffer from endemic diseases because of consumption of agricultural products lacking in Se. One such area in Northeast China where Keshan disease and Kashin-Beck disease originated, was selected for investigating the geochemistry, influencing factors, and risks of Se in the agroecosystems. Analysis of field samples indicates that the Se deficiency in soil is significantly reduced compared with that of several decades ago, and 62.6% of soils are now Se-sufficient in the southern Songnen Plain. However, Se in crop products remains low due to weak soil-plant transfer, resulting in high risks of Se deficiency related diseases in the rural population of this area. Structural equation modeling, principal component analysis, and other statistical analyses revealed that climate conditions and soil physical and chemical properties are the key factors influencing the spatial distribution of soil Se. Extensive use of agricultural fertilizers may indirectly inhibit the migration of Se from soil to plants. Ensuring sufficient Se contents in agricultural products to meet the minimum daily requirements of residents remains a challenge in Se-deficient areas, especially in the increased agricultural production environment in China.


Assuntos
Doença de Kashin-Bek , Selênio , China/epidemiologia , Fertilizantes/análise , Humanos , Selênio/análise , Solo
10.
Food Chem ; 334: 127475, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32688176

RESUMO

Although numerous types of organisms have been used to enrich selenium, a low-cost and efficient organism is yet to be identified. This study aimed to develop a new means of selenium enrichment using Tenebrio molitor larvae. Our results indicated that the total selenium content in larvae was increased 83-fold to 54.21 ± 1.25 µg/g, and of this content, organic selenium accounted for over 97% after feeding the larvae with 20 µg/g of sodium selenite. Selenium was distributed unequally in the protein fraction with following order: alkali-soluble protein-bound selenium (36.32%) > salt-soluble protein-bound selenium (19.41%) > water-soluble protein-bound selenium (17.03%) > alcohol-soluble protein-bound selenium (3.21%). Additionally, 81% of the selenium within the soluble proteins was distributed in subunits possessing molecular weights of <40 kDa. After hydrolysis by alcalase, the protein hydrolysate of selenium-enriched larvae possessing 75% selenium recovery exhibited stronger antioxidant and immunoregulatory activities than those of regular larvae.


Assuntos
Antioxidantes/farmacologia , Fatores Imunológicos/farmacologia , Proteínas de Insetos/metabolismo , Hidrolisados de Proteína/farmacologia , Selênio/farmacocinética , Tenebrio/metabolismo , Adulto , Aminoácidos/análise , Aminoácidos/metabolismo , Animais , Antioxidantes/metabolismo , Eritrócitos/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Humanos , Hidrólise , Fatores Imunológicos/metabolismo , Proteínas de Insetos/farmacologia , Larva/efeitos dos fármacos , Larva/metabolismo , Camundongos , Hidrolisados de Proteína/metabolismo , Células RAW 264.7 , Selênio/análise , Subtilisinas/química , Subtilisinas/metabolismo , Tenebrio/efeitos dos fármacos
11.
Chemosphere ; 263: 127920, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32822936

RESUMO

Arsenic (As) and selenium (Se) pollution caused by coal combustion is receiving increasing concerns. The environmental impacts of As/Se are determined not only by stack emission but also by leaching process from combustion byproducts. For a better control of As/Se emission from As/Se-enriched coal combustion, this study investigated the migration and emission behavior of As/Se in a circulating fluidized bed (CFB) power plant equipped with fabric filter (FF) and wet flue gas desulfurization (WFGD) system. The results demonstrated that arsenic was both enriched in bottom ash (41.4-47.6%) and fly ash (52.4-58.6%), while selenium was mainly captured by fly ash (73.9-83.4%). Limestone injection into furnace promoted As/Se retention in ash residues. Arsenic was mainly converted into arsenate in high-temperature regions and partly trapped in bottom ash as arsenite. In contrast, selenium capture mainly occurred in low-temperature flue gas by the formation of selenite, because of the poor thermal stability of most selenite. Triplet-tank method can totally remove arsenic in WFGD wastewater. And 18.4-58.7% of selenium was removed, resulting from the precipitation of Se4+ anions with highly soluble Se6+ anions remaining in wastewater. The concentrations of As and Se in the stack emission were 0.25-1.02 and 0.96-2.24 µg/m3, receptively. The CFB boiler equipped with FF + WFGD was shown to provide good control of the As/Se emission into the atmosphere. Leaching tests suggested that more attention should be paid to As leachability from fly ash/gypsum, and Se leachability from gypsum/sludge.


Assuntos
Poluentes Atmosféricos/análise , Arsênico/análise , Centrais Elétricas , Selênio/análise , Atmosfera , Leitos , Carbonato de Cálcio , Sulfato de Cálcio , Carvão Mineral/análise , Cinza de Carvão/química , Monitoramento Ambiental , Gases
12.
Chemosphere ; 263: 127908, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32835973

RESUMO

The effects of breccia pipe uranium mining in the Grand Canyon watershed (Arizona) on ecological and cultural resources are largely unknown. We characterized the exposure of biota to uranium and co-occurring ore body elements during active ore production and at a site where ore production had recently concluded. Our results indicate that biota have taken up uranium and other elements (e.g., arsenic, cadmium, copper, molybdenum, uranium) from exposure to ore and surficial contamination, like blowing dust. Results indicate the potential for prolonged exposure to elements and radionuclides upon conclusion of active ore production. Mean radium-226 in deer mice was up to 4 times greater than uranium-234 and uranium-238 in those same samples; this may indicate a potential for, but does not necessarily imply, radium-226 toxicity. Soil screening benchmarks for uranium and molybdenum and other toxicity thresholds for arsenic, copper, selenium, uranium (e.g., growth effects) were exceeded in vegetation, invertebrates, and rodents (Peromyscus spp., Thomomys bottae, Tamias dorsalis, Dipodomys deserti). However, the prevalence and severity of microscopic lesions in rodent tissues (as direct evidence of biological effects of uptake and exposure) could not be definitively linked to mining. Our data indicate that land managers might consider factors like species, seasonal changes in environmental concentrations, and bioavailability, when determining mine permitting and remediation in the Grand Canyon watershed. Ultimately, our results will be useful for site-specific ecological risk analysis and can support future decisions regarding the mineral extraction withdrawal in the Grand Canyon watershed and elsewhere.


Assuntos
Exposição à Radiação , Poluentes Radioativos da Água/toxicidade , Animais , Arsênico/análise , Cádmio/análise , Cobre/análise , Invertebrados , Camundongos , Mineração , Monitoramento de Radiação , Radioisótopos/análise , Rádio (Elemento) , Roedores , Selênio/análise , Solo , Urânio/análise
13.
Ecotoxicol Environ Saf ; 207: 111216, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32916525

RESUMO

Low concentrations of selenium (Se) are beneficial for plant growth. Foliar Se application at high concentrations is toxic to plants due to the formation of reactive oxygen species (ROS). This study characterized Se toxicity symptoms using X-ray fluorescence (XRF) technique in response to foliar Se application in cowpea plants. Five Se concentrations (0, 10, 25, 50, 100 e 150 g ha-1) were sprayed on leaves as sodium selenate. The visual symptoms of Se toxicity in cowpea leaves were separated into two stages: I) necrotic points with an irregular distribution and internerval chlorosis at the leaf limb border (50-100 g ha-1); II) total chlorosis with the formation of dark brown necrotic lesions (150 g ha-1). Foliar Se application at 50 g ha-1 increased photosynthetic pigments and yield. Ultrastructural analyses showed that Se foliar application above 50 g ha-1 disarranged the upper epidermis of cowpea leaves. Furthermore, Se application above 100 g ha-1 significantly increased the hydrogen peroxide concentration and lipid peroxidation inducing necrotic leaf lesions. Mapping of the elements in leaves using the XRF revealed high Se intensity, specifically in leaf necrotic lesions accompanied by calcium (Ca) as a possible attenuating mechanism of plant stress. The distribution of Se intensities in the seeds was homogeneous, without specific accumulation sites. Phosphorus (P) and sulfur (S) were found primarily located in the embryonic region. Understanding the factors involved in Se accumulation and its interaction with Ca support new preventive measurement technologies to prevent Se toxicity in plants.


Assuntos
Selênio/metabolismo , Vigna/metabolismo , Peroxidação de Lipídeos , Fósforo/análise , Fotossíntese , Folhas de Planta/química , Sementes/química , Ácido Selênico/análise , Selênio/análise , Enxofre/análise
14.
Sci Total Environ ; 749: 141350, 2020 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-33370896

RESUMO

Odontocetes are apex predators that, despite accumulating mercury (Hg) to high concentrations in their tissues, show few signs of Hg toxicity. One method of Hg detoxification in odontocetes includes the sequestering of Hg in toxicologically inert mercury selenide (HgSe) compounds. To explore the tissue-specific accumulation of Hg and Se and the potential protective role of Se against Hg toxicity, we measured the concentrations of total mercury (THg) and selenium (Se) in multiple tissues from 11 species of odontocetes that stranded along the northern Gulf of Mexico coast [Florida (FL) and Louisiana (LA)]. Tissues were collected primarily from bottlenose dolphins (Tursiops truncatus; n = 93); however, individuals from species in the following 8 genera were also sampled: Feresa (n = 1), Globicephala (n = 1), Grampus (n = 2), Kogia (n = 5), Mesoplodon (n = 1), Peponocephala (n = 4), Stenella (n = 9), and Steno (n = 1). In all species, mean THg concentrations were greatest in the liver and lowest in the blubber, lung, or skin. In contrast, in most species, mean Se concentrations were greatest in the liver, lung, or skin, and lowest in the blubber. For all species combined, Se:Hg molar ratios decreased with increasing THg concentration in the blubber, kidney, liver, lung, and skin following an exponential decay relationship. In bottlenose dolphins, THg concentrations in the kidney, liver, and lung were significantly greater in FL dolphins compared to LA dolphins. On average, in bottlenose dolphins, Se:Hg molar ratios were approximately 1:1 in the liver and >1:1 in blubber, kidney, lung, and skin, suggesting that Se likely protects against Hg toxicity. However, more research is necessary to understand the variation in Hg accumulation within and among species and to assess how Hg, in combination with other environmental stressors, influences odontocete population health.


Assuntos
Mercúrio , Selênio , Poluentes Químicos da Água , Animais , Monitoramento Ambiental , Florida , Golfo do México , Humanos , Louisiana , Mercúrio/análise , Selênio/análise
15.
J Agric Food Chem ; 68(51): 15061-15073, 2020 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-33315396

RESUMO

Selenium is an essential microelement required for biological processes. Traditional selenium supplements (selenite and selenomethionine mainly) remain concerns due to toxicity and bioavailability. In recent decades, biofortification strategies have been applied to produce selenium-enriched edible plants to address the challenges of superior nutritional quality requirements. Plant-derived selenium-containing proteins/peptides offer potential health benefits beyond the basic nutritional requirements of Se. Highly nucleophilic seleno-amino acids, special peptide sequences, and favorable bioavailability contribute to the biological activities of selenium-containing proteins/peptides, such as antioxidant, antihypertensive, anti-inflammatory, and immunomodulatory effects. However, their applications on a commercial scale are insufficient owing to the complexity of purification and identification techniques and the sparse information on bioavailability and metabolism. In this review, selenium status, structural features, bioactivities, structure-activity relationships, and bioavailability, as well as the mechanisms underlying the bioactivities and metabolism of plant-derived selenium-containing proteins/peptides, are summarized and discussed for their nutraceutical use.


Assuntos
Peptídeos/química , Proteínas de Plantas/química , Plantas/química , Selênio/análise , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Biofortificação , Humanos , Selênio/farmacologia
16.
Artigo em Inglês | MEDLINE | ID: mdl-33375039

RESUMO

Kashin-Beck Disease (KBD) is one of major endemic diseases in China. In this study, we estimated the health loss from KBD in Qamdo district of Tibet using the years lived with disability (YLD) metric and investigated the influence of environmental selenium (Se) on it by multiple regression model. The results showed that YLD rates produced a different ranking of health loss of KBD from that produced by prevalence rates between Basu and Luolong County, with higher health loss from KBD (43.61 YLD/1000) but lower prevalence (17.86%) in Basu County. YLD rates in two counites were both highest for the 45-64 years age group. Compared with the prevalence rate, the YLD rate had a closer relation to environmental Se and was significantly negatively correlated with Se in both soil and highland barley. The multiple linear regression further revealed that Se contents in cultivated soil and highland barley were main influencing factors for the health loss of KBD, which could explain 90.5% of the variation in YLD rates. The information obtained highlights the significance of the YLD metric in exploring the environmental etiology of KBD and provides important information on which to base decisions on future prevention and control of endemic diseases.


Assuntos
Doença de Kashin-Bek , Selênio , Hordeum/química , Humanos , Doença de Kashin-Bek/epidemiologia , Doença de Kashin-Bek/etiologia , Selênio/efeitos adversos , Selênio/análise , Solo/química , Tibet/epidemiologia
17.
Arch Environ Contam Toxicol ; 79(3): 354-370, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33025049

RESUMO

Heavy metals threaten communities near biodiversity hotspots, as their protein sources come from the environment. This study assessed Hg, Cd, and Se concentrations in fish, as well as the magnitude of exposure and hematological conditions of adult citizens from Puerto Nariño (Colombian Amazon). Among fish samples, greater Hg concentrations were found in higher trophic level species, including Rhaphiodon vulpinus (880 ± 130 ng/g) and Pseudoplatystoma tigrinum (920 ± 87 ng/g). These species presented the highest hazard quotients and lowest Se:Hg molar ratios among those studied, showing their consumption represents a health risk to consumers. Moreover, some samples of Mylossoma duriventre and Prochilodus magdalenae had Cd levels greater than the regulated limit (100 ng/g). The average total Hg (T-Hg) concentrations in human hair and blood were 5.31 µg/g and 13.7 µg/L, respectively. All hair samples exceeded the 1.0 µg/g threshold set by the USEPA, whereas 93% of the volunteers had T-Hg blood levels greater than 5 µg/L, suggesting elevated exposure. The mean Cd level was 3.1 µg/L, with 21% of samples surpassing 5 µg/L, value at which mitigating actions should be taken. Eighty-four percent of participants presented Se deficiencies (<100 µg/L). There was a significant association between fish consumption and T-Hg in hair (ρ = 0.323; p = 0.032) and blood (ρ = 0.381; p = 0.011). In this last matrix, Se correlated with Cd content, whereas lymphocytes were inversely linked to Hg concentrations. The results of this study show that there is  extensive exposure to Hg in fish, the consumption of which may promote detrimental impacts on hematology parameters within the community.


Assuntos
Monitoramento Biológico/métodos , Cádmio/análise , Peixes/metabolismo , Cabelo/química , Mercúrio/análise , Selênio/análise , Adulto , Animais , Cádmio/metabolismo , Colômbia , Exposição Dietética/análise , Feminino , Contaminação de Alimentos/análise , Humanos , Masculino , Mercúrio/metabolismo , Selênio/metabolismo
18.
Ecotoxicol Environ Saf ; 203: 111016, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32888590

RESUMO

Selenium (Se) is considered a beneficial element to higher plants based on its regulation of antioxidative system under abiotic or biotic stresses. However, the limit of beneficial and toxic physiological effects of Se is very narrow. In the present study, the antioxidant performance, nutritional composition, long-distance transport of Se, photosynthetic pigments, and growth of Coffea arabica genotypes in response to Se concentration in solution were evaluated. Five Coffea arabica genotypes (Obatã, IPR99, IAC125, IPR100 and Catucaí) were used, which were grown in the absence and presence of Se (0 and 1.0 mmol L-1) in nutrient solution. The application of 1 mmol L-1 Se promoted root browning in all genotypes. There were no visual symptoms of leaf toxicity, but there was a reduction in the concentration of phosphorus and sulfur in the shoots of plants exposed to high Se concentration. Except for genotype Obatã, the coffee seedlings presented strategies for regulating Se uptake by reducing long-distance transport of Se from roots to shoots. The concentrations of total chlorophyll, total pheophytin, and carotenoids were negatively affected in genotypes Obatã, IPR99, and IAC125 upon exposure to Se at 1 mmol L-1. H2O2 production was reduced in genotypes IPR99, IPR100, and IAC125 upon exposure to Se, resulting in lower activity of superoxide dismutase (SOD), and catalase (CAT). These results suggest that antioxidant metabolism was effective in regulating oxidative stress in plants treated with Se. The increase in sucrose, and decrease in SOD, CAT and ascorbate peroxidase (APX) activities, as well as Se compartmentalization in the roots, were the main biochemical and physiological modulatory effects of coffee seedlings under stress conditions due to excess of Se.


Assuntos
Antioxidantes/metabolismo , Coffea/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Selênio/farmacologia , Coffea/genética , Coffea/metabolismo , Coffea/fisiologia , Genótipo , Oxirredução , Fotossíntese/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Plântula/efeitos dos fármacos , Plântula/genética , Plântula/metabolismo , Plântula/fisiologia , Selênio/análise , Selênio/metabolismo , Especificidade da Espécie
19.
Environ Monit Assess ; 192(10): 662, 2020 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-32979107

RESUMO

The centrifuge-less dispersive liquid-liquid microextraction (DLLME) technique was used to separate selenium species in aqueous samples. According to the salting-out effect, a simple approach was used to eliminate the centrifugation step. The optimization of the independent variables was performed using chemometric methods. Under optimal conditions, this methodology was statistically validated. The linearity was between 20 and 300 µg L-1. The limit of detection and quantification were calculated 3.4 µg L-1 and 10.4 µg L-1, respectively. The values of reproducibility and repeatability were determined ≤ 9.5% and ≤ 6.4, respectively. The possibility of the method was successfully assessed by analyzing the analytes in real samples clarified satisfactory recoveries (98.1-101.4% for Se (IV) and 98.4-101.5% for Se (VI)).


Assuntos
Microextração em Fase Líquida , Selênio/análise , Poluentes Químicos da Água/análise , Centrifugação , Monitoramento Ambiental , Limite de Detecção , Reprodutibilidade dos Testes
20.
Bull Environ Contam Toxicol ; 105(5): 798-805, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32909074

RESUMO

In 1963, selenosis occurred in Yutangba Village, Enshi City, China. Subsequently, local residents migrated to a new area of Yutangba to avoid high selenium (Se) exposure. In this study, 19 soil samples, 43 food samples, 60 hair samples and 58 plasma samples from local residents were randomly collected in New Yutangba Village. The mean total Se concentrations in cultivated soil samples were 1753.6 ± 742.8 µg/kg (n = 14). The estimated daily Se intake in New Yutangba Village decreased to 63.2 ± 39.8 µg/day, slightly higher than the recommended dietary Se intake for adults in China (60 µg/day). The mean Se concentrations in hair and plasma samples were 549.7 ± 165.2 µg/kg (n = 60) and 98.4 ± 32.1 µg/L (n = 58), respectively. The result indicated that appropriate activities, such as relocation, consuming a mixture of local foods and market foods containing low Se concentration, could effectively reduce the risk of high Se exposure.


Assuntos
Exposição Dietética/análise , Monitoramento Ambiental/métodos , Cabelo/química , Selênio/análise , Poluentes do Solo/análise , Solo/química , Adulto , China , Humanos , Distribuição Aleatória , Selênio/sangue , Poluentes do Solo/sangue
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