Use of enriched 74Se and 77Se in combination with isotope pattern deconvolution to differentiate and determine endogenous and supplemented selenium in lactating rats

International Nuclear Information System (INIS)

Gonzalez Iglesias, H.; Fernandez Sanchez, M.L.; Garcia Alonso, J.I.; Sanz-Medel, A.

2007-01-01

A quantitative methodology has been developed to differentiate between endogenous and supplemented selenium in lactating rats using two enriched selenium isotopes. Lactating rats were fed for 2 weeks with formula milk containing one enriched Se isotope, 77 Se, as the metabolic tracer. The isotopic composition of selenium in serum and urine samples was then measured by collision cell ICP-MS after the addition of a solution containing another enriched isotope, 74 Se, as quantitation tracer, before analysis. Isotope pattern deconvolution allowed the transformation of measured Se isotopic abundances into concentrations of natural abundance (endogenous) selenium and enriched 77 Se (supplemented) present in the samples. The proposed methodology was validated using serum and urine reference materials spiked with both 77 Se and 74 Se. The obtained results are discussed in terms of selenium exchange and half-life in lactating rats (11-12 days) and selenium levels in serum in comparison with non-supplemented rats and control rats after maternal feeding. (orig.)

Rumen microorganisms decrease bioavailability of inorganic selenium supplements

Science.gov (United States)

Despite the availaility of selenium (Se)-enriched trace mineral supplements, we have observed low Se status in cattle and sheep offered traditional inorganic Se supplements. Reasons for this may include inadequate intake or low bioavailability of inorganic Se sources. The objective of this study w...

The Effect on Selenium Concentrations of a Randomized Intervention with Fish and Mussels in a Population with Relatively Low Habitual Dietary Selenium Intake

Science.gov (United States)

Outzen, Malene; Tjønneland, Anne; Larsen, Erik H.; Andersen, Klaus K.; Christensen, Jane; Overvad, Kim; Olsen, Anja

2015-01-01

Selenium status of the Danish population is below that assumed optimal for the suggested protective effects against chronic diseases, including certain cancers. Fish and shellfish are important dietary sources of selenium in Denmark. We investigated the effect of increased fish and mussel intake on selenium blood concentrations in a population with relatively low habitual dietary selenium intake. We randomly assigned 102 healthy men and women (all non-smokers) aged 48–76 years to an intervention group (n = 51) or a control group (n = 51). Intervention participants received 1000 g fish and mussels/week for 26 weeks (~50 μg selenium/day). Controls received no intervention. Non-fasting blood samples were taken and whole blood selenium was determined using inductively coupled plasma-mass spectrometry (ICP-MS), and plasma selenoprotein P (SelP) was determined by high performance liquid chromatography coupled to ICP-MS. All available observations were included in linear multiple regression analysis to evaluate the effect of the intervention. The difference in mean change for intervention compared with control persons was 14.9 ng/mL (95% CI: 10.2, 19.7) for whole blood selenium, and 7.0 ng/mL (95% CI: 3.1, 10.9) for plasma SelP (Weeks 0–26). Selenium concentrations were significantly increased after 26 weeks of intervention, albeit to a lower degree than expected. PMID:25599275

Analysis of Selenium Contents in Plant Foods Consumed by Korean adults

Energy Technology Data Exchange (ETDEWEB)

Lee, Okhee; Kim, Kangsung [Kyonghee Univ., Yongin (Korea, Republic of); Moon, Jonghwa; Chung, Yongsam [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2014-10-15

Se exhibited a relatively small range of adequate ingestion level for health. An accurate investigation of Se consumption in Korean population has been rare because the database of food containing selenium is rather small. The table of Se content in food is a basic tool for calculating selenium intake. Since diet is the main source of Se intake, the Se content in various foods and personal dietary practices would be primarily determined to evaluate the nutritional status of Se for a population. To evaluate the Se intake levels of a population, a Se food database should be generated based on data produced by high-precision analytical techniques. In addition, this database should contain the Se contents of foods that are regularly consumed by the studied population. Plant foods contain lower Se levels when compared to animal products. However, grains, potatoes, starches, and legumes have been the main sources of carbohydrates and proteins in traditional Korean diet. Since grains such as rice are a staple food and remain the most consumed foods in Korea, their contribution to dietary Se intake might be considerable. However, no reports on the selenium content from plant foods have been compiled for the Korean population. The goal of this study was to measure the Se content in common consumed plant foods such as grain, potatoes, legumes and their products. The legume rich in protein contained relatively high amount of Se when compared to other plant food type. The raw wheat and wheat product which have been imported from abroad showed higher amount of Se than rice mostly produced in Korea. The acquired Se value is useful to assess the Se intake of Korean adults from plant foods.

Analysis of Selenium Contents in Plant Foods Consumed by Korean adults

International Nuclear Information System (INIS)

Lee, Okhee; Kim, Kangsung; Moon, Jonghwa; Chung, Yongsam

2014-01-01

Se exhibited a relatively small range of adequate ingestion level for health. An accurate investigation of Se consumption in Korean population has been rare because the database of food containing selenium is rather small. The table of Se content in food is a basic tool for calculating selenium intake. Since diet is the main source of Se intake, the Se content in various foods and personal dietary practices would be primarily determined to evaluate the nutritional status of Se for a population. To evaluate the Se intake levels of a population, a Se food database should be generated based on data produced by high-precision analytical techniques. In addition, this database should contain the Se contents of foods that are regularly consumed by the studied population. Plant foods contain lower Se levels when compared to animal products. However, grains, potatoes, starches, and legumes have been the main sources of carbohydrates and proteins in traditional Korean diet. Since grains such as rice are a staple food and remain the most consumed foods in Korea, their contribution to dietary Se intake might be considerable. However, no reports on the selenium content from plant foods have been compiled for the Korean population. The goal of this study was to measure the Se content in common consumed plant foods such as grain, potatoes, legumes and their products. The legume rich in protein contained relatively high amount of Se when compared to other plant food type. The raw wheat and wheat product which have been imported from abroad showed higher amount of Se than rice mostly produced in Korea. The acquired Se value is useful to assess the Se intake of Korean adults from plant foods

Selenium Characterization In The Global Rice Supply Chain

Science.gov (United States)

For up to 1 billion people worldwide, insufficient dietary intake of selenium (Se) is a serious health constraint. Cereals are the dominant Se source for those on low protein diets, as typified by the global malnourished population. With crop Se content constrained largely by u...

Developmental selenium exposure and health risk in daily foodstuffs: A systematic review and meta-analysis.

Science.gov (United States)

Ullah, Habib; Liu, Guijian; Yousaf, Balal; Ali, Muhammad Ubaid; Abbas, Qumber; Munir, Mehr Ahmed Mujtaba; Mian, Md Manik

2018-03-01

Selenium (Se) is a trace mineral and an essential nutrient of vital importance to human health in trace amounts. It acts as an antioxidant in both humans and animals, immunomodulator and also involved in the control of specific endocrine pathways. The aim of this work is to provide a brief knowledge on selenium content in daily used various foodstuffs, nutritional requirement and its various health consequences. In general, fruits and vegetables contain low content of selenium, with some exceptions. Selenium level in meat, eggs, poultry and seafood is usually high. For most countries, cereals, legumes, and derivatives are the major donors to the dietary selenium intake. Low level of selenium has been related with higher mortality risk, dysfunction of an immune system, and mental failure. Selenium supplementation or higher selenium content has antiviral outcomes and is necessary for effective reproduction of male and female, also decreases the threat of chronic disease (autoimmune thyroid). Generally, some advantages of higher content of selenium have been shown in various potential studies regarding lung, colorectal, prostate and bladder cancers risk, nevertheless results depicted from different trials have been diverse, which perhaps indicates the evidence that supplementation will merely grant advantage if the intakes of a nutrient is deficient. In conclusion, the over-all people should be advised against the usage of Se supplements for prevention of cardiovascular, hepatopathies, or cancer diseases, as advantages of Se supplements are still ambiguous, and their haphazard usage could result in an increased Se toxicity risk. The associations among Se intake/status and health, or disease risk, are complicated and need exposition to notify medical practice, to improve dietary recommendations, and to develop adequate communal health guidelines. Copyright © 2017 Elsevier Inc. All rights reserved.

Sodium selenite/selenium nanoparticles (SeNPs) protect cardiomyoblasts and zebrafish embryos against ethanol induced oxidative stress.

Science.gov (United States)

Kalishwaralal, Kalimuthu; Jeyabharathi, Subhaschandrabose; Sundar, Krishnan; Muthukumaran, Azhaguchamy

2015-10-01

Alcoholic cardiomyopathy is the damage caused to the heart muscles due to high level of alcohol consumption resulting in enlargement and inflammation of the heart. Selenium is an important trace element that is beneficial to human health. Selenium protects the cells by preventing the formation of free radicals in the body. In the present study, protein mediated synthesis of SeNPs was investigated. Two different sizes of SeNPs were synthesized using BSA and keratin. The synthesized SeNPs were characterized by scanning electron microscopy (SEM) with elemental composition analysis Energy Dispersive X-ray spectroscopy(EDX) and X-ray diffraction (XRD). This study demonstrates the in vitro and in vivo antioxidative effects of sodium selenite and SeNPs. Further selenium and SeNPs were evaluated for their ability to protect against 1% ethanol induced oxidative stress in H9C2 cell line. The selenium and SeNPs were found to reduce the 1% ethanol-induced oxidative damage through scavenging intracellular reactive oxygen species. The selenium and SeNPs could also prevent pericardial edema induced ethanol treatment and reduced apoptosis and cell death in zebrafish embryos. The results indicate that selenium and SeNPs could potentially be used as an additive in alcoholic beverage industry to control the cardiomyopathy. Copyright © 2015 Elsevier GmbH. All rights reserved.

Use of enriched {sup 74}Se and {sup 77}Se in combination with isotope pattern deconvolution to differentiate and determine endogenous and supplemented selenium in lactating rats

Energy Technology Data Exchange (ETDEWEB)

Gonzalez Iglesias, H.; Fernandez Sanchez, M.L.; Garcia Alonso, J.I.; Sanz-Medel, A. [University of Oviedo, Department of Physical and Analytical Chemistry, Faculty of Chemistry, Oviedo (Spain)

2007-10-15

A quantitative methodology has been developed to differentiate between endogenous and supplemented selenium in lactating rats using two enriched selenium isotopes. Lactating rats were fed for 2 weeks with formula milk containing one enriched Se isotope, {sup 77}Se, as the metabolic tracer. The isotopic composition of selenium in serum and urine samples was then measured by collision cell ICP-MS after the addition of a solution containing another enriched isotope, {sup 74}Se, as quantitation tracer, before analysis. Isotope pattern deconvolution allowed the transformation of measured Se isotopic abundances into concentrations of natural abundance (endogenous) selenium and enriched {sup 77}Se (supplemented) present in the samples. The proposed methodology was validated using serum and urine reference materials spiked with both {sup 77}Se and {sup 74}Se. The obtained results are discussed in terms of selenium exchange and half-life in lactating rats (11-12 days) and selenium levels in serum in comparison with non-supplemented rats and control rats after maternal feeding. (orig.)

Effects of selenium supplementation on four agricultural crops.

Science.gov (United States)

Carvalho, Kathleen M; Gallardo-Williams, Maria T; Benson, Robert F; Martin, Dean F

2003-01-29

Agricultural crops can be used either to remediate selenium-contaminated soils or to increase the daily selenium intake of consumers after soil supplementation using inorganic or organic selenium sources. In this study, four agricultural crops were examined for potential selenium enhancement. Soils containing tomato, strawberry, radish, and lettuce plants were supplemented with either an inorganic or an organic form of selenium. Two different soils, i.e., low Se and high Se containing, were also used. Statistically significant differences in appearance, fruit production, and fresh weights of the fruit produced were studied. Next, the amount of selenium retained in the edible fruits, nonedible plant, and soil for each was analyzed by acid digestion followed by hydride generation atomic absorption analysis. Finally, inhibition effects on the seeds of the agricultural plants were studied. The results show that supplementation with an inorganic form of selenium led to higher retention in the plants, with a maximum of 97.5% retained in the edible portion of lettuce plants.

Selenium Se and tellurium Te

International Nuclear Information System (INIS)

Busev, A.I.; Tiptsova, V.G.; Ivanov, V.M.

1978-01-01

The basic methods for determining selenium and tellurium in various objects are presented. The bichromatometric determination of Te in cadmium, zinc and mercury tellurides is based on oxidation of Te(4) to (6) in H 2 SO 4 with potassium bichromate. In steels, Te is determined photometrically with the aid of KI. The determination is hindered by Fe(3), Cu(2), Bi(3) and Se(4) ions, which must be separated. The extraction-photometric determination of Te in native sulfur is carried out with the aid of 5-mercapto-3-(naphthyl-2)-1,3,4-thiadiazolthione-2 (pH=4.8-5.0). The dyed complex is readily extracted with chloroform and benzene. The spectrophotometric determination of Te in selenium is performed with the aid of 3,5-diphenylpyrazoline-1-dithiocarbamate of sodium. Te is determined in commercial indium, arsenic and their semiconductor compounds photometrically with the aid of copper diethyldithiocarbamate. The method permits determining 5x10 -5 % Te in a weighed amount of 0.5 g. The chloride complex of Te(4) with diantipyriodolpropylmethane is quantitatively extracted with dichloroethane from hydrochloric acid solutions. Thus, any amounts of Te can be separated from Se and determined photometrically. The extraction-photometric determination of Te in commercial lead and bismuth is carried out with the aid of pyrazolone derivatives, in commercial copper with the aid of diantipyridolpropylmethane, and in ores (more than 0.01% Te) with the aid of bismuthol 2. Also described is the extraction-polarographic determination of Te in sulfide ores

Selenium Enrichment of Horticultural Crops.

Science.gov (United States)

Puccinelli, Martina; Malorgio, Fernando; Pezzarossa, Beatrice

2017-06-04

The ability of some crops to accumulate selenium (Se) is crucial for human nutrition and health. Selenium has been identified as a cofactor of the enzyme glutathione peroxidase, which is a catalyzer in the reduction of peroxides that can damage cells and tissues, and can act as an antioxidant. Plants are the first link in the food chain, which ends with humans. Increasing the Se quantity in plant products, including leafy and fruity vegetables, and fruit crops, without exceeding the toxic threshold, is thus a good way to increase animal and human Se intake, with positive effects on long-term health. In many Se-enriched plants, most Se is in its major organic form. Given that this form is more available to humans and more efficient in increasing the selenium content than inorganic forms, the consumption of Se-enriched plants appears to be beneficial. An antioxidant effect of Se has been detected in Se-enriched vegetables and fruit crops due to an improved antioxidative status and to a reduced biosynthesis of ethylene, which is the hormone with a primary role in plant senescence and fruit ripening. This thus highlights the possible positive effect of Se in preserving a longer shelf-life and longer-lasting quality.

Selenium Enrichment of Horticultural Crops

Directory of Open Access Journals (Sweden)

Martina Puccinelli

2017-06-01

Full Text Available The ability of some crops to accumulate selenium (Se is crucial for human nutrition and health. Selenium has been identified as a cofactor of the enzyme glutathione peroxidase, which is a catalyzer in the reduction of peroxides that can damage cells and tissues, and can act as an antioxidant. Plants are the first link in the food chain, which ends with humans. Increasing the Se quantity in plant products, including leafy and fruity vegetables, and fruit crops, without exceeding the toxic threshold, is thus a good way to increase animal and human Se intake, with positive effects on long-term health. In many Se-enriched plants, most Se is in its major organic form. Given that this form is more available to humans and more efficient in increasing the selenium content than inorganic forms, the consumption of Se-enriched plants appears to be beneficial. An antioxidant effect of Se has been detected in Se-enriched vegetables and fruit crops due to an improved antioxidative status and to a reduced biosynthesis of ethylene, which is the hormone with a primary role in plant senescence and fruit ripening. This thus highlights the possible positive effect of Se in preserving a longer shelf-life and longer-lasting quality.

Determination of total selenium and Se-77 in isotopically enriched human samples by ICP-dynamic reaction cell-MS

DEFF Research Database (Denmark)

Sloth, Jens Jørgen; Larsen, Erik Huusfeldt; Bügel, Susanne H.

2003-01-01

and the digested faecal samples were diluted using an aqueous diluent containing 0.5% Triton X-100, 2% nitric acid and 3% methanol. Selenium was detected as Se-76, Se-77 and Se-80 by ICP- DRC- MS. Selenium originating from the natural isotope abundance yeast and other selenium sources from the diet was determined...

Dietary Selenium Intake and Subclinical Hypothyroidism: A Cross-Sectional Analysis of the ELSA-Brasil Study.

Science.gov (United States)

Andrade, Gustavo R G; Gorgulho, Bartira; Lotufo, Paulo A; Bensenor, Isabela M; Marchioni, Dirce M

2018-05-30

Selenium (Se) participates in several enzymatic reactions necessary for regulating the homeostasis of thyroid hormones. We aimed to analyze the association between dietary Se intake and subclinical hypothyroidism. Baseline data from the Longitudinal Study of Adult Health (Estudo Longitudinal de Saúde do Adulto-ELSA-Brasil) in Brazil were analyzed, with a final sample size of 14,283 employees of both sexes aged 35⁻74 years. Dietary data was collected using a previously validated food frequency questionnaire. Subclinical hypothyroidism was categorized as thyroid-stimulating hormone levels of >4.0 IU/mL and free prohormone thyroxine levels within normal limits, without administering drugs for thyroid disease. A multiple logistic regression model was used to assess the relationship between the presence of subclinical hypothyroidism and tertiles of Se consumption. The prevalence of subclinical hypothyroidism in the study sample was 5.4% (95% confidence interval [CI], 3.8⁻7.0%). Compared with the first tertile of Se intake, the second (odds ratio [OR], 0.79; 95% CI, 0.65⁻0.96%) and third (OR, 0.72; 95% CI, 0.58⁻0.90%) tertiles were inversely associated with subclinical hypothyroidism, however further research is needed to confirm the involvement of Se in subclinical hypothyroidism using more accurate methodologies of dietary assessment and nutritional status to evaluate this relationship.

[Effect of selenium on serum TGAb, TMAb, FT3, FT4 and TSH of rats with excessive intake of iodine].

Science.gov (United States)

Chi, Haiyan; Zhou, Yuping; Li, Li

2012-07-01

To investigate the effect of selenium on the TGAb, TMAb, FT3, FT4 and TSH level of rats with excessive intake of iodine. Wistar rats were divided into three groups by random:normal control, high iodine group and high iodine plus selenium group. Rats in the high iodine plus selenium group were lavaged with sodium selenite for 10 weeks. The levels of serum TGAb, TMAb, FT3, FT4 and TSH were tested at different time of the experiment. There were no significant change on levels of FT3, FT4 and TSH (P > 0.05). The levels of TGAb and TMAb in the high iodine group were increased slowly (P iodine plus selenium group. Excessive intake of iodine might induce goiter, and selenium might have antagonistic effect on it.

Simultaneous speciation of arsenic (As(III), MMA, DMA, and As(V)) and selenium (Se(IV), Se(VI), and SeCN{sup -}) in petroleum refinery aqueous streams

Energy Technology Data Exchange (ETDEWEB)

Tonietto, Gisele B.; Godoy, Jose M.; Oliveira, Ana Cristina [Pontificia Universidade Catolica do Rio de Janeiro, Rio de Janeiro, RJ (Brazil); Souza, Marcia V. de [Petrobras/Cenpes, Research and Development Center, Rio de Janeiro (Brazil)

2010-07-15

High-performance liquid chromatography (HPLC) coupled to an ICP-MS with an octapole reaction system (ORS) has been used to carry out quantitative speciation of selenium (Se) and arsenic (As) in the stream waters of a refining process. The argon dimers interfering with the {sup 78}Se and {sup 80}Se isotopes were suppressed by pressurizing the octapole chamber with 3.1 mL min{sup -1} H{sub 2} and 0.5 mL min{sup -1} He. Four arsenic species arsenite - As(III), arsenate (As(V)), monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA) - and three inorganic Se species - selenite Se(IV), selenate Se(VI), and selenocyanate (SeCN{sup -}) - were separated in a single run by ion chromatography (IC) using gradient elution with 100 mmol L{sup -1} NH{sub 4}NO{sub 3}, pH 8.5, adjusted by addition of NH{sub 3}, as eluent. Repeatabilities of peak position and of peak area evaluation were better than 1% and about 3%, respectively. Detection limits (as 3{sigma} of the baseline noise) were 81, 56, and 75 ng L{sup -1} for Se(IV), Se(VI), and SeCN{sup -}, respectively, and 22, 19, 25, and 16 ng L{sup -1} for As(III), As(V), MMA, and DMA, respectively. Calibration curve R {sup 2} values ranged between 0.996 and 0.999 for the arsenic and selenium species. Column recovery for ion chromatography was calculated to be 97 {+-} 6% for combined arsenic species and 98 {+-} 3% for combined selenium species. Because certified reference materials for As and Se speciation studies are still not commercially available, in order to check accuracy and precision the method was applied to certified reference materials, BCR 714, BCR 1714, and BCR 715 and to two different refinery samples - inlet and outlet wastewater. The method was successfully used to study the quantitative speciation of selenium and arsenic in petroleum refinery wastewaters. (orig.)

Determinants of selenium status in healthy adults

Directory of Open Access Journals (Sweden)

Hoeg Antonia

2011-07-01

Full Text Available Abstract Background Selenium (Se status in non-deficient subjects is typically assessed by the Se contents of plasma/serum. That pool comprises two functional, specific selenoprotein components and at least one non-functional, non-specific components which respond differently to changes in Se intake. A more informative means of characterizing Se status in non-deficient individuals is needed. Methods Multiple biomarkers of Se status (plasma Se, serum selenoprotein P [SEPP1], plasma glutathione peroxidase activity [GPX3], buccal cell Se, urinary Se were evaluated in relation to selenoprotein genotypes (GPX1, GPX3, SEPP1, SEP15, dietary Se intake, and parameters of single-carbon metabolism in a cohort of healthy, non-Se-deficient men (n = 106 and women (n = 155. Conclusions Plasma Se concentration was 142.0 ± 23.5 ng/ml, with GPX3 and serum-derived SEPP1 calculated to comprise 20% and 34%, respectively, of that total. The balance, comprised of non-specific components, accounted for virtually all of the interindividual variation in total plasma Se. Buccal cell Se was associated with age and plasma homocysteine (hCys, but not plasma Se. SEPP1 showed a quadratic relationship with body mass index, peaking at BMI 25-30. Urinary Se was greater in women than men, and was associated with metabolic body weight (kg0.75, plasma folate, vitamin B12 and hCys (negatively. One GPX1 genotype (679T/T was associated with significantly lower plasma Se levels than other allelic variants. Selenium intake, estimated from food frequency questionnaires, did not predict Se status as indicated by any biomarker. These results show that genotype, methyl-group status and BMI contribute to variation in Se biomarkers in Se-adequate individuals.

Effects of Interaction between Cadmium (Cd) and Selenium (Se) on Grain Yield and Cd and Se Accumulation in a Hybrid Rice (Oryza sativa) System.

Science.gov (United States)

Huang, Baifei; Xin, Junliang; Dai, Hongwen; Zhou, Wenjing

2017-11-01

A pot experiment was conducted to investigate the interactive effects of cadmium (Cd) and selenium (Se) on their accumulation in three rice cultivars, which remains unclear. The results showed that Se reduced Cd-induced growth inhibition, and increased and decreased Se and Cd concentrations in brown rice, respectively. Cadmium concentrations in all tissues of the hybrid were similar to those in its male parent yet significantly lower than those in its female parent. Selenium reduced Cd accumulation in rice when Cd concentration exceeded 2.0 mg kg -1 ; however Se accumulation depended on the levels of Cd exposure. Finally, Cd had minimal effect on Se translocation within the three cultivars. We concluded that Cd concentration in brown rice is a heritable trait, making crossbreeding a feasible method for cultivating high-yield, low-Cd rice cultivars. Selenium effectively decreased the toxicity and accumulation of Cd, and Cd affected Se uptake but not translocation.

Evaluation of Selenium Content of Plant Samples Collected from Indigenous Sources for Se-supplementation

International Nuclear Information System (INIS)

Mahmud, T.; Sosan, A.; Rehman, R.; Abbas, A.

2010-01-01

Selenium contents were evaluated in different plant species such as Canola (Brassica napus), Sunflower (Helianthus annus), Turmeric (Curcuma longa), Soyabean Seeds (Glycine max) and Akk (Calotropis procera) in order to access their possibility for Se-supplementation. The dry ash of bulb of Turmeric and seeds of Canola, Sunflower, and Soyabean were digested in concentrated HNO/sub 3/, HClO/sub 4/ and HCl to obtain selenium (IV). After adding different reagents, stable blue colored complex was formed. From this colored complex, selenium (IV) was determined by UV/visible spectrophotometer. This work was carried out in an attempt to obtain information concerning the amount of selenium present in different plants. It was observed that Akk is a good accumulator of selenium as it contains almost 30 mu g selenium per gram and can be used for different medicinal applications. (author)

The determination of methylmercury, total mercury and total selenium in human hair

International Nuclear Information System (INIS)

1987-01-01

This Reference Method describes the determination of methylmercury in human hair by gas liquid chromatography. It is designed for biological monitoring of selected individuals and population groups with a possible intake of methylmercury exceeding the recommended Provisional Tolerable Weekly Intake (PTWI) through contaminated seafood, as part of a project on the evaluation of methylmercury in Mediterranean populations and related health hazards. The method, however, is also applicable to other regions. The method involves direct determination of methylmercury by gas liquid chromatography. The sample is disintegrated in a solution of sodium hydroxide, methylmercury is extracted from an aliquot of the solution into toluene and, after purification, a small volume is injected into a chromatographic column, filled with polyethyleneglycol succinate on Diatomite AW. Methylmercury in the gaseous mixture is detected with an electron capture detector and its amount determined by comparing the peak height with those of appropriate standards. The next Reference Method describes the determination of selenium in human hair (and other indicative tissues) by gas liquid chromatography and is designed for biological monitoring of selected individuals and population groups in the Mediterranean region with a possible intake of methylmercury exceeding the recommended Provisional Tolerable Weekly Intake (PTWI) through contaminated seafood. The data are intended to establish a possible correlation between methylmercury intake and levels of selenium in the subjects monitored. Selenium in the solvent phase is determined by gas liquid chromatography using an electron capture detector. The above method has been selected because selenium is determined in conjunction with methylmercury, both of which require competence in gas chromatographic techniques. Reliable result for total selenium, however, will also be obtained by the following techniques: a) Atomic absorption spectrophotometry; b

Organic and inorganic sources of zinc, copper and selenium in diets for dairy cows: intake, blood metabolic profile, milk yield and composition

Directory of Open Access Journals (Sweden)

Cristina Simões Cortinhas

2012-06-01

Full Text Available The present study was carried out with the objective of evaluating the effects of feeding dairy cows with organic or inorganic sources of zinc (Zn, copper (Cu and selenium (Se on blood concentrations of these minerals, blood metabolic profiles, nutrient intake and milk yield and composition. Nineteen Holstein cows were selected and randomly assigned to two groups for receiving organic (n = 9 or inorganic (n = 10 sources of Zn, Cu and Se from 60 days before the expected date of calving to 80 days of lactation. Samples of feed, orts and milk were collected for analysis. Body condition score (BCS was determined and blood samples were collected for analysis of Zn, Cu and Se concentrations, as well as for metabolic profile. Supplying organic or inorganic sources of Zn, Cu, and Se did not affect dry matter and nutrient intake, blood metabolic profile, milk yield and composition, plasma concentration of these minerals, and BCS or change the BCS in cows from 60 days before the expected date of calving to 80 days of lactation. An effect of time was observed on all feed intake variables, plasma concentrations of Zn and Se, milk yield, milk protein content, BCS and change in BCS.

Selenium concentration of maize grain in South Africa and possible ...

African Journals Online (AJOL)

Casey W

reviewed paper: Proc. ... maize grain is a staple food for humans and a major ingredient in the diets of intensively fed livestock. Therefore, Se in ..... Dietary reference intakes for vitamin C, vitamin E, selenium and carotenoids. National Research.

Dietary Selenium (Se) and Copper (Cu) Interact to Affect Homocysteine Metabolism in Rats

Science.gov (United States)

Our previous studies have shown that selenium (Se) is protective against dimethylhydrazine (DMH)-induced preneoplastic colon cancer lesions, and protection against DNA damage has been hypothesized to be one mechanism for the anticancer effect of Se. The present study was designed to determine whethe...

Selenium in human milk: An Australian study

International Nuclear Information System (INIS)

Cumming, F.J.; Fardy, J.J.; Woodward, D.R.

1991-01-01

The aims of this Australian study were to determine (total) selenium concentration in breast milk and in maternal blood, and to assess the relationship between the two. The authors also aimed to assess the infants' selenium intake. Twenty lactating women from Brisbane (Queensland) participated in the study, at 6-12 weeks post-partum. Small samples (approximately 10 ml) of breast-milk were manually expressed at the beginning and end of a mid-morning feed, from the first breast offered at that feed. Venous blood samples (10 ml) were also collected from the mothers. Milk and blood samples were analyzed by neutron activation analysis. Babies' milk intake over a 24-hour period was estimated using a modified test-weighing technique. Infant selenium intakes were calculated directly for each infant, using his/her mother's milk selenium level and his/her own 24-hour breast milk intake. The mean selenium concentration in maternal blood was 101 (±SD 19) ng/g and in maternal serum 81 (±15) ng/g. Breast milk selenium concentrations (11.9 ± 3.5 ng/g) were fairly low by international standards. There was no correlation between selenium concentrations in milk and blood (or serum). The infants' 24-hour breast-milk intakes were 856 ± 172 g, and their selenium intakes were 10.7 ± 4.1 μg per day

Dietary selenium in the Glasgow area

International Nuclear Information System (INIS)

Cross, J.D.; Raie, R.M.; Smith, H.

1978-01-01

A typical diet for people in the Glasgow area is analysed and an estimate is made of the daily intake of selenium for the average person (234 μg). Meat, poultry and bread products contribute 65% of the total selenium consumed. There is a significant loss of selenium on cooking but the concentration in the diet is high compared with the estimated requirement. Selenium levels in prepared infant foods, artificial milk and natural milk are reported. Those infants on artificial milk feeds have a selenium intake equivalent to that of adults (3 μg/kg) while those on natural milk or prepared infant foods have an intake of 6 μg/kg. Adult and infant tissue selenium levels are established and are shown to be in equilibrium with the diet. There is no concentration in man as a result of his position at the top of the food chain. Sudden infant death cannot be related to selenium levels in human tissue or diet. (author)

Estimation of selenium bioavailability from human, cow's, goat and sheep milk by an in vitro method

NARCIS (Netherlands)

Shen, L.; Dael, van P.; Luten, J.; Deelstra, H.

1996-01-01

The trace element selenium (Se) has been recognized to be essential for human health. The dependence of infants on milk as their principal food source, generally low in Se content, makes them more vulnerable to inadequate Se intake. The present study compared the Se availability as estimated by a

Selenium, cadmium and diazinon insecticide in tissues of rats after peroral exposure

Directory of Open Access Journals (Sweden)

Róbert Toman

2017-01-01

Full Text Available The concentrations of selenium (Se, cadmium (Cd and diazinon (DZN in selected tissues of rats after an oral administration in various combinations were analyzed. Male rats were orally dosed with diazinon (40 mg.L-1, diazinon (40 mg.L-1 +selenium (5 mg.L-1, diazinon (40 mg.L-1 +cadmium (30 mg.L-1, and diazinon (40 mg.L-1 +selenium (5 mg.L-1 +cadmium (30 mg.L-1 in drinking water. After 90 days of per oral administration of compounds, the samples of liver, kidney, muscle tissue (m. quadriceps femoris, and adipose tissue were collected. The content of DZN was analyzed using Gas Chromatography - Mass Spectrometry (GC-MS, Cd was analyzed using an Electrothermal Atomic Absorption Spectrometry (ETAAS and Se using a Hydride Generation Atomic Absorption Spectrometry (HG-AAS methods. Cadmium significantly increased in liver and kidney after DZN +Cd and DZN +Se +Cd administration. Se significantly increased in liver of DZN +Se, DZN +Se +Cd and DZN +Cd exposed rats, in kidney of DZN +Se and DZN +Se +Cd and DZN +Cd, and in muscle of DZN +Se +Cd group. Highest DZN content was found in the adipose tissue in DZN, DZN +Cd and DZN +Se +Cd but not in combined exposure with Se. Anyway, the differences between the control and experimental groups were not significant. The results indicate that cadmium and selenium accumulate mainly in liver, kidney and selenium also in muscle after p.o. administration but diazinon concentrations increases were not signifcant. The co-administration of diazinon, Se and Cd affects the content of these compounds in the organism and the accumulation rate depends on the combination of administered compounds. Diazinon and cadmium could contribute to the selenium redistribution in the organism after the peroral intake.

Selenium biofortification of broccoli and carrots grown in soil amended with Se-enriched hyperaccumulator Stanleya pinnata

Science.gov (United States)

Amending soils with Se-hyperaccumulator plant derived sources of selenium (Se) may be useful for increasing Se content in food crops in Se-deficient regions of the world. In this study, we evaluated total Se and the different chemical species of Se in broccoli and carrots grown in soils amended with...

Low selenium status affects arsenic metabolites in an arsenic exposed population with skin lesions.

Science.gov (United States)

Huang, Zhi; Pei, Qiuling; Sun, Guifan; Zhang, Sichum; Liang, Jiang; Gao, Yi; Zhang, Xinrong

2008-01-01

The antagonistic effects between selenium (Se) and arsenic (As) suggest that low selenium status plays important roles in arsenism development. However, no study has been reported for humans suffering from chronic arsenic exposure with low selenium status. Sixty-three subjects were divided into 2 experimental groups by skin lesions (including hyperkeratosis, depigmentation, and hyperpigmentation). Total urine and serum concentrations of arsenic and selenium were determined by ICP-MS with collision/reaction cell. Arsenic species were analysed by ICP-MS coupled with HPLC. The mean concentration of As in the drinking waters was 41.5 microg/l. The selenium dietary intake for the studied population was 31.7 microg Se/d, and which for the cases and controls were 25.9 and 36.3 microg Se/d, respectively. Compared with the controls, the skin lesions cases had lower selenium concentrations in serum and urine (41.4 vs 49.6 microg/l and 71.0 vs 78.8 microg/l, respectively), higher inorganic arsenic (iAs) in serum (5.2 vs 3.4 microg/l, PiAs in serum and urine (20.2) vs 16.9% and 18.3 vs 14.5%, respectively, PiAs and its inhibition to be biotransformed to DMA occurred in human due to chronic exposure of low selenium status.

Continued selenium biofortification of carrots and broccoli grown in soils once amended with Se-enriched S. pinnata

Science.gov (United States)

Selenium (Se) biofortification has been practiced in Se-deficient regions throughout the world primarily by adding inorganic sources of Se to the soil. Adding organic sources of Se could be useful as an alternative Se amendment for the production of Se-biofortified food crops needed in Se-deficient ...

The Voltammetric Analysis of Selenium Electrodeposition from H2SeO3 Solution on Gold Electrode

Directory of Open Access Journals (Sweden)

Kowalik R.

2015-04-01

Full Text Available The different voltammetry techniques were applied to understand the process of selenium deposition from sulfate solution on gold polycrystalline electrode. By applying the cycling voltammetry with different scan limits as well as the chronoamper-ometry combined with the cathodic and anodic linear stripping voltammetry, the different stages of the deposition of selenium were revealed. It was found that the process of reduction of selenous acid on gold surface exhibits a multistage character. The cyclic voltammetry results showed four cathodic peaks which are related to the surface limited phenomena and which coincide with the bulk deposition process. The fifth cathodic peak is related to the reduction of bulk deposited Se0 to Se-2 ions. Furthermore, the connection of anodic peaks with cathodic ones confirmed the surface limited process of selenium deposition, bulk deposition and reduction to Se-2. Additionally, the cathodic linear stripping voltammetry confirms the process of H2SeO3 adsorption on gold surface. The experiments confirmed that classical voltammetry technique proved to be a very powerful tool for analyzing the electrochemical processes related with interfacial phenomena and electrodeposition.

Determinants of Selenium Intake in a High HIV Prevalence Fishing Community in Bondo District, Kenya

OpenAIRE

Samwel Boaz Otieno; Fred Were; Ephantus Kabiru; Kaunda Waza

2016-01-01

A study was done to establish determinants of selenium intake in a high HIV prevalence fishing community in the Pala Bondo district, Kenya. It was established that most of the respondents (61%) were small holder Farmers and Fishermen {χ2 (1, N=386) p

On-line pre-reduction of Se(VI) by thiourea for selenium speciation by hydride generation

International Nuclear Information System (INIS)

Qiu Jianhua; Wang Qiuquan; Ma Yuning; Yang Limin; Huang Benli

2006-01-01

In this study, thiourea (TU) was novelly developed as a reduction reagent for on-line pre-reduction of selenium(VI) before conventional hydride generation (HG) by KBH 4 /NaOH-HCl. After TU on-line pre-reduction, the HG efficiency of Se(VI) has been greatly improved and because even higher than that of the same amount of Se(IV) obtained in the conventional HG system. The possible pre-reduction mechanism is discussed. The detection limit (DL) of selenate reaches 10 pg mL -1 when using on-line TU pre-reduction followed by HG atomic fluorescence detection. When TU pre-reduction followed by HG is used as an interface between ion-pair high performance liquid chromatography and atomic fluorescence spectrometry, selenocystine, selenomethionine, selenite and selenate can be measured simultaneously and quantitatively. The DLs of these are 0.06, 0.08, 0.05 and 0.04 ng mL -1 , respectively, and the relative standard deviations of 9 duplicate runs for all the 4 species are less than 5%. Furthermore, it was successfully applied to Se speciation analysis of cultured garlic samples, and validated by determination of total selenium and selenium species in certified reference material NIST 1946

Determination of cesium and selenium in cultivated mushrooms using radionuclide X-ray fluorescence technique

International Nuclear Information System (INIS)

Racz, L.; Bumbalova, A.; Harangozo, M.; Toelgyessy, J.; Tomecek, O.

2000-01-01

Cesium and selenium intake of cultivated mushrooms (Agaricus bisporus), with these elements previously added to culture medium, has been examined from the viewpoint of health- and environmental protection. The process of measuring has been carried out by the radionuclide X-ray fluorescence technique. Treatments of the elementary substance with Se salt appears to influence the Se content of the mushrooms to a significant extent. Cs intake is of considerable importance, as this element is accumulated by mushrooms. (author)

Selenium in edible mushrooms.

Science.gov (United States)

Falandysz, Jerzy

2008-01-01

Selenium is vital to human health. This article is a compendium of virtually all the published data on total selenium concentrations, its distribution in fruitbody, bioconcentration factors, and chemical forms in wild-grown, cultivated, and selenium-enriched mushrooms worldwide. Of the 190 species reviewed (belonging to 21 families and 56 genera), most are considered edible, and a few selected data relate to inedible mushrooms. Most of edible mushroom species examined until now are selenium-poor (cesarea, A. campestris, A. edulis, A. macrosporus, and A. silvaticus. A particularly rich source of selenium could be obtained from selenium-enriched mushrooms that are cultivated on a substrate fortified with selenium (as inorganic salt or selenized-yeast). The Se-enriched Champignon Mushroom could contain up to 30 or 110 microg Se/g dw, while the Varnished Polypore (Ganoderma lucidum) could contain up to 72 microg Se/g dw. An increasingly growing database on chemical forms of selenium of mushrooms indicates that the seleno-compounds identified in carpophore include selenocysteine, selenomethionine, Se-methylselenocysteine, selenite, and several unidentified seleno-compounds; their proportions vary widely. Some aspects of environmental selenium occurrence and human body pharmacokinetics and nutritional needs will also be briefly discussed in this review.

Monodispersed spherical shaped selenium nanoparticles (SeNPs) synthesized by Bacillus subtilis and its toxicity evaluation in zebrafish embryos

Science.gov (United States)

Chandramohan, Subburaman; Sundar, Krishnan; Muthukumaran, Azhaguchamy

2018-02-01

Selenium is one of the essential elements involved in antioxidative and antiinflammatory effects in human body. By naturally, selenium ions are metabolised and converted into nano selenium. Now a days there is an increasing attention on applications of nanoparticles in therapeutic field. In the present study Bacillus subtilis was used to convert sodium selenite to SeNPs. The synthesized SeNPs were characterized by Fourier Transform Infrared Spectroscopy (FTIR), X Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) coupled with Energy Dispersive X ray spectroscopy (EDX). The presence of SeNPs was confirmed by the formation of red colour. The bands were sharp with broad absorption peaks at 3562 cm-1 and 1678-1 cm in FTIR which showed that the bacterial proteins were responsible for the reduction of sodium selenite to SeNPs. The average size of the SeNPs was 334 nm and were spherical in shape with uniform distribution. The XRD data confirmed that SeNPs were of amorphous in nature. The zeta potential of SeNPs was negative in charge which indicated high stability. In the present study zebrafish embryos were used to study the toxicity of SeNPs and the results showed that the concentration beyond 10 μg ml-1 leads to toxic effects in embryos/hatchlings. The lesser concentration of SeNPs can be useful in various biomedical applications.

Selenium in bone health: roles in antioxidant protection and cell proliferation.

Science.gov (United States)

Zeng, Huawei; Cao, Jay J; Combs, Gerald F

2013-01-10

Selenium (Se) is an essential trace element for humans and animals, and several findings suggest that dietary Se intake may be necessary for bone health. Such findings may relate to roles of Se in antioxidant protection, enhanced immune surveillance and modulation of cell proliferation. Elucidation of the mechanisms by which Se supports these cellular processes can lead to a better understanding of the role of this nutrient in normal bone metabolism. This article reviews the current knowledge concerning the molecular functions of Se relevant to bone health.

On-line pre-reduction of Se(VI) by thiourea for selenium speciation by hydride generation

Energy Technology Data Exchange (ETDEWEB)

Qiu Jianhua [Department of Chemistry and the MOE Key Laboratory of Analytical Sciences, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005 (China); Wang Qiuquan [Department of Chemistry and the MOE Key Laboratory of Analytical Sciences, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005 (China)]. E-mail: qqwang@xmu.edu.cn; Ma Yuning [Department of Chemistry and the MOE Key Laboratory of Analytical Sciences, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005 (China); Yang Limin [Department of Chemistry and the MOE Key Laboratory of Analytical Sciences, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005 (China); Huang Benli [Department of Chemistry and the MOE Key Laboratory of Analytical Sciences, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005 (China)

2006-07-15

In this study, thiourea (TU) was novelly developed as a reduction reagent for on-line pre-reduction of selenium(VI) before conventional hydride generation (HG) by KBH{sub 4}/NaOH-HCl. After TU on-line pre-reduction, the HG efficiency of Se(VI) has been greatly improved and because even higher than that of the same amount of Se(IV) obtained in the conventional HG system. The possible pre-reduction mechanism is discussed. The detection limit (DL) of selenate reaches 10 pg mL{sup -1} when using on-line TU pre-reduction followed by HG atomic fluorescence detection. When TU pre-reduction followed by HG is used as an interface between ion-pair high performance liquid chromatography and atomic fluorescence spectrometry, selenocystine, selenomethionine, selenite and selenate can be measured simultaneously and quantitatively. The DLs of these are 0.06, 0.08, 0.05 and 0.04 ng mL{sup -1}, respectively, and the relative standard deviations of 9 duplicate runs for all the 4 species are less than 5%. Furthermore, it was successfully applied to Se speciation analysis of cultured garlic samples, and validated by determination of total selenium and selenium species in certified reference material NIST 1946.

Revised and extended analysis of doubly ionized selenium: Se III

International Nuclear Information System (INIS)

Tauheed, A; Hala

2012-01-01

The spectrum of selenium was recorded on a 3 m normal incidence vacuum spectrograph of the Antigonish laboratory (Canada) in the wavelength region 300-2080 Å using a triggered spark source. The theoretical structure of doubly ionized selenium (Se III) was predicted by Cowan's multi-configuration interaction code. The ground configuration of Se III is 4s 2 4p 2 and the excited configurations are of the type 4s 2 4pnd (n≥4), 4s 2 4pns (n≥5) and the inner shell excitation gives rise to the 4s4p 3 configuration. The 4s 2 4p 2 -[4s4p 3 +4s 2 4p (4d+5d+6d+7d+5s+6s+7s+8s)] transition array has been analyzed. Several earlier reported levels have been revised and four new configurations have been added. All the levels of these configurations have been established. More than 180 spectral lines have been identified in this spectrum. A total of 75 energy levels belonging to the above-mentioned configurations have been established. Least-squares fitted parametric and Hartree-Fock calculations were used to interpret the observed spectrum. Excellent agreement with theoretical calculations was noticed. The standard deviation of least-squares fit is only 110 cm -1 . The ionization potential of Se III was found to be 255 650±150 cm -1 (31.696±0.018 eV). The accuracy of our wavelengths for sharp lines is better than ±0.005 Å.

Determination of selenium in cereals, legumes and dry fruits from southeastern Spain for calculation of daily dietary intake

International Nuclear Information System (INIS)

Diaz-Alarcon, J.P.; Navarro-Alarcon, M.; Lopez-Garcia de la Serrana, H.; Lopez-Martinez, M.C.

1996-01-01

Hydride generation atomic absorption spectrometry was used to determine selenium content in cereals, legumes and dry fruits from the coast of the province of Granada (southeastern Spain). Accuracy was assured using both a NIST SRM 1572 and recovery experiments. The precision expressed as relative standard deviation (RSD) varied between 6.50% for seeds and 15.98% for bread. The highest selenium concentrations were found for dry fruits (294.6 ng/g), followed by legumes (111.8 ng/g), and the lowest for cereals (27.8 ng/g). Considering the average daily individual consumption of these foods in Andalusia (southern Spain), the daily dietary intake of selenium supplied by this source is 15.36 μg/day for an adult. The content of total selenium in corn samples taken from the zone is independent of both human and industrial activities (P 0.05)

The Cultivation and SeleniumEnrichment of SeleniumEnriched Earthworm

Directory of Open Access Journals (Sweden)

SUN Xiao-fei

2014-12-01

Full Text Available As a bio-carrier, Eisenia fetida was fed with cow dung that added with sodium selenite in order to transfer inorganic selenium(Se into organic selenium. Targeting on survival rate and selenium content, the effects of five Se concentrations(0, 20, 40, 60, 80, 100 mg·kg-1 and four cultivation periods(15, 30, 45, 60 don earthworm growth and Se contents were investigated. The cultivation method with high survival rate, high Se content of earthworm and short breeding time would be screened out. The experimental results showed that the earthworm survival rate decreased and the Se content in earthworm increased with the increase of Se application and the extension of breeding time. The most optimummethod was screened out when the Se concentration was 80 mg·kg-1 and the cultivation period was 45 days, Se content in earthworm was up to 33.25 mg·kg-1.

Vegetarianism and colorectal cancer risk in a low-selenium environment: effect modification by selenium status? A possible factor contributing to the null results in British vegetarians.

Science.gov (United States)

Sobiecki, Jakub G

2017-08-01

Despite the consistent findings of lower total cancer incidence in vegetarians than in meat-eaters in the UK, the results of studies of colorectal cancer (CRC) risk in British vegetarians have largely been null. This was in contrast to the hypothesis of a decreased risk of CRC in this population due to null intake of red and processed meats and increased intake of fibre. Although the data are inconsistent, it has been suggested that selenium (Se) status may influence CRC risk. A literature review was performed of studies on CRC risk in vegetarians, Se intakes and status in vegetarians, and changes of Se intakes and status in the UK throughout the follow-up periods of studies on CRC risk in British vegetarians. Vegetarians in the UK and other low-Se areas were found to have low Se intakes and status compared to non-vegetarians. There was some evidence of a reverse J-shaped curve of Se intakes and status in the UK throughout the last three decades. These presumed patterns were followed by the changes in CRC mortality or incidence in British vegetarians during this period. Available data on Se intake and status in British vegetarians, as well as the relationship between their secular changes in the UK and changes in CRC risk in this dietary group, are compatible with the hypothesis that low Se status may contribute to the largely null results of studies of CRC risk in vegetarians in the UK.

Microbial selenium sulfide reduction for selenium recovery from wastewater

NARCIS (Netherlands)

Hageman, S.P.W.; Weijden, van der R.D.; Stams, A.J.M.; Cappellen, van P.; Buisman, C.J.N.

2017-01-01

Microbial reduction of selenium sulfide (SeS2) is a key step in a new treatment process to recover selenium from selenate and selenite streams. In this process, selenate is first reduced to selenite, and subsequently selenite is reduced by sulfide and precipitates from the solution as SeS2. The

Selenium content in selected foods from the Greek market and estimation of the daily intake

International Nuclear Information System (INIS)

Pappa, Eleni C.; Pappas, Athanasios C.; Surai, Peter F.

2006-01-01

The total selenium content of foods purchased from the North West part of Greece was determined using hydride generation atomic fluorescence spectroscopy. The results of this study were within the range from other countries. The overall mean average of selenium concentration of the foods examined, in decreasing order, was found in sesame seeds (783.1 ng g -1 ), fish (246 ng g -1 ), legumes (162.5 ng g -1 ), eggs (123 ng g -1 ), bread (91.9 ng g -1 ), meat (71.7 ng g -1 ), cheese (69.8 ng g -1 ), yoghurt (23.6 ng g -1 ), nuts (19.6 ng g -1 ), milk (15.4 ng g -1 ), vegetables (6.5 ng g -1 ) and fruits (3.4 ng g -1 ). Considering the average daily individual consumption of these foods by Greeks, the average daily dietary intake of selenium supplied by this source is 39.3 μg per capita

Selenium content in selected foods from the Greek market and estimation of the daily intake

Energy Technology Data Exchange (ETDEWEB)

Pappa, Eleni C. [National Agricultural Research Foundation, Dairy Research Institute, Katsikas 45221, Ioannina (Greece)]. E-mail: instgala@otenet.gr; Pappas, Athanasios C. [Avian Science Research Centre, Animal Health Group, SAC, Auchincruive, Ayr KA6 5HW (United Kingdom); Surai, Peter F. [Avian Science Research Centre, Animal Health Group, SAC, Auchincruive, Ayr KA6 5HW (United Kingdom); Division of Environmental and Evolutionary Biology, University of Glasgow, Glasgow, G12 8QQ, Scotland (United Kingdom)

2006-12-15

The total selenium content of foods purchased from the North West part of Greece was determined using hydride generation atomic fluorescence spectroscopy. The results of this study were within the range from other countries. The overall mean average of selenium concentration of the foods examined, in decreasing order, was found in sesame seeds (783.1 ng g{sup -1}), fish (246 ng g{sup -1}), legumes (162.5 ng g{sup -1}), eggs (123 ng g{sup -1}), bread (91.9 ng g{sup -1}), meat (71.7 ng g{sup -1}), cheese (69.8 ng g{sup -1}), yoghurt (23.6 ng g{sup -1}), nuts (19.6 ng g{sup -1}), milk (15.4 ng g{sup -1}), vegetables (6.5 ng g{sup -1}) and fruits (3.4 ng g{sup -1}). Considering the average daily individual consumption of these foods by Greeks, the average daily dietary intake of selenium supplied by this source is 39.3 {mu}g per capita.

Benefits of raising crops and animals naturally enriched with selenium in areas with selenium deficiency

International Nuclear Information System (INIS)

Dzhudich, I.S.

2008-01-01

Selenium (Se) is implicated in the protection of body tissues against oxidative stress, maintenance of defences against infection, and modulation of growth and development. The natural environment has a profound influence on its contents in the food chain and the development and distribution of Se responsive diseases. To overcome the Se deficiency problem and assure safe and adequate Se intakes, different methods were developed. Its efficiency depends on Se compounds absorption, its nutritional availability, long-term retention, convertibility of tissue Se stores into biologically active forms and the history of Se nutrition, influencing the proportion of absorbed retained, or excreted Se from diet. Since the dominant metabolically active Se forms are found in proteins as seleno analogues of sulphur amino acids, rather than selenotrisulphides and other acid labile Se compounds, we developed our own procedure for foliar enrichment of crops with Se, enabling the production of crops and animals with adequate Se content in low Se areas. By foliar application of Se salts, we optimize Se contents of many parameters important for plants quality, thus contributing to the better status of many essential, in diet often deficient nutrients. The utilization of these crops in animal nutrition, contributes to the nutritive value of animal products not only due to adequate Se content, but also higher values of other quality parameters. Consumption of such produced crops and animal products by humans in areas with low dietary Se intake has shown to have significant overall health benefits

Selenium accumulation by plants

Science.gov (United States)

White, Philip J.

2016-01-01

Background Selenium (Se) is an essential mineral element for animals and humans, which they acquire largely from plants. The Se concentration in edible plants is determined by the Se phytoavailability in soils. Selenium is not an essential element for plants, but excessive Se can be toxic. Thus, soil Se phytoavailability determines the ecology of plants. Most plants cannot grow on seleniferous soils. Most plants that grow on seleniferous soils accumulate 100 mg Se kg–1 dry matter. These plants are considered to be Se accumulators. Some species can even accumulate Se concentrations of 1000–15 000 mg Se kg–1 dry matter and are called Se hyperaccumulators. Scope This article provides an overview of Se uptake, translocation and metabolism in plants and highlights the possible genetic basis of differences in these between and within plant species. The review focuses initially on adaptations allowing plants to tolerate large Se concentrations in their tissues and the evolutionary origin of species that hyperaccumulate Se. It then describes the variation in tissue Se concentrations between and within angiosperm species and identifies genes encoding enzymes limiting the rates of incorporation of Se into organic compounds and chromosomal loci that might enable the development of crops with greater Se concentrations in their edible portions. Finally, it discusses transgenic approaches enabling plants to tolerate greater Se concentrations in the rhizosphere and in their tissues. Conclusions The trait of Se hyperaccumulation has evolved several times in separate angiosperm clades. The ability to tolerate large tissue Se concentrations is primarily related to the ability to divert Se away from the accumulation of selenocysteine and selenomethionine, which might be incorporated into non-functional proteins, through the synthesis of less toxic Se metabilites. There is potential to breed or select crops with greater Se concentrations in their edible tissues, which

Selenium assimilation and loss by an insect predator and its relationship to Se subcellular partitioning in two prey types

Energy Technology Data Exchange (ETDEWEB)

Dubois, Maitee [Institut national de la recherche scientifique - Eau, Terre et Environnement, Universite du Quebec, Quebec City, Quebec, G1K 9A9 (Canada); Hare, Landis [Institut national de la recherche scientifique - Eau, Terre et Environnement, Universite du Quebec, Quebec City, Quebec, G1K 9A9 (Canada)], E-mail: landis@ete.inrs.ca

2009-03-15

Subcellular selenium (Se) distributions in the oligochaete Tubifex tubifex and in the insect Chironomus riparius did not vary with Se exposure duration, which was consistent with the observations that the duration of prey Se exposure had little influence on either Se assimilation or loss by a predatory insect (the alderfly Sialis velata). However, these two prey types differed in how Se was distributed in their cells. Overall, the predator assimilated a mean of 66% of the Se present in its prey, which was similar to the mean percentage of Se in prey cells (62%) that was theoretically available for uptake (that is, Se in the protein and organelle fractions). Likewise, data for cadmium, nickel and thallium suggest that predictions of trace element transfer between prey and predator are facilitated by considering the subcellular partitioning of these contaminants in prey cells. - Selenium assimilation by a predatory aquatic insect depends on Se availability in the cells of its prey.

Selenium assimilation and loss by an insect predator and its relationship to Se subcellular partitioning in two prey types

International Nuclear Information System (INIS)

Dubois, Maitee; Hare, Landis

2009-01-01

Subcellular selenium (Se) distributions in the oligochaete Tubifex tubifex and in the insect Chironomus riparius did not vary with Se exposure duration, which was consistent with the observations that the duration of prey Se exposure had little influence on either Se assimilation or loss by a predatory insect (the alderfly Sialis velata). However, these two prey types differed in how Se was distributed in their cells. Overall, the predator assimilated a mean of 66% of the Se present in its prey, which was similar to the mean percentage of Se in prey cells (62%) that was theoretically available for uptake (that is, Se in the protein and organelle fractions). Likewise, data for cadmium, nickel and thallium suggest that predictions of trace element transfer between prey and predator are facilitated by considering the subcellular partitioning of these contaminants in prey cells. - Selenium assimilation by a predatory aquatic insect depends on Se availability in the cells of its prey

Biological effects of selenium and relationships with carcinogenesis

Energy Technology Data Exchange (ETDEWEB)

Diplock, A.T.

1984-01-01

Selenium is an element that is both essential, at low levels of dietary intake, and toxic, at high levels, to man and a wide range of animals. The purpose of the communication is to review the evidence for the involvement of hyper- and hypo-selenosis in the etiology of cancer. High levels of selenium intake have been blamed for an increase in cancer, dental caries and an array of other conditions. Critical evaluation of the evidence, however, leads to the conclusion that such claims have little substance. On the other hand, low levels of selenium intake may be associated with an increased incidence of certain forms of cancer and there appears to be an inverse relationship between blood selenium levels and cancer death rate in the US. Keshan Disease, in the People's Republic of China has only been shown to occur in populations severely depleted of selenium. In well nourished populations there is no evidence to indicate that selenium supplements have any prophylactic or therapeutic benefit against human diseases such as cancer, cardiovascular disease or cystic fibrosis. 33 references.

Dietary intake of Arsenic, Iodine and Selenium by adolescents in three Orphanages in Southern Ghana using Radiochemical Neutron activation analysis

International Nuclear Information System (INIS)

Adotey, K. D.

2011-07-01

Adolescents require optimum dietary supply of the essential trace minerals iodine (I) and selenium (Se). Their dietary exposure to arsenic (As), due to its natural presence in the diet, should be at levels that provides ample safety. Due to the late recognition of the critical nature of adolescent nutrition, there is scarce and almost non-existence of data on the adolescents dietary intake of As, I and Se; making it difficult for public health nutritionists to assess the adequacy of the dietary intake. The absence of data has also adversely affected the formulation of policies on adolescent nutrition and its integration into existing nutrition and health care programmes in Ghana. The dietary intake of As, I and Se for adolescents (12-15years) in three residential care orphanages, (Osu, Tutu- Akwapim, and Teshie), in Southern Ghana, have been evaluated by sampling their 24- hour total duplicate diets (including water) for 7-consecutive days using the duplicate diet sampling technique. The mass fraction of As, I and Se in the pooled blended lyophilized homogenates of duplicate diets was determined by radiochemical neutron activation analysis (RNAA). The validity of the RNAA methods for As, I and Se determinations were respectively checked by analyses of NIST SRM 1548a (Typical Diet). The chemical yields (recovery of the respective radiochemical separation of As, I and Se were 90- 92%, 83-88%, and 78-85%. The mass fraction of arsenic in the lyophilized diets for Osu, Tutu-Akwapim and Teshie were 134 ± 104 [46-240], 146 ± 87 [39-355], and 189 ± 123 [69-348] ng As g -1 lyophilized matter. The dietary exposures to As were 47 ± 23 [17-84], 58 ± 44 [16-125] and 67 ± 28 [24-117] μg As day -1 for Osu, Tutu-Akwapim and Teshie orphanages respectively. The mass fraction of I in the lyophilized diets were 287 ± 95 [206-397], 286 ± 109 [201-386], and 961 ± 142 [588-1766] ng I g -1 lyophilized matter, for Osu, Tutu-Akwapim and Teshie respectively. The dietary intake of I

Low-temperature photoluminescence of CuSe2 nano-objects in selenium thin films

Directory of Open Access Journals (Sweden)

Martina Gilić

2017-06-01

Full Text Available Thin films of CuSe2 nanoparticles embedded in selenium matrix were prepared by vacuum evaporation method on a glass substrate at room temperature. The optical properties of the films were investigated by photoluminescence spectroscopy (T=20-300K and UV-VIS spectroscopy (T = 300K. Surface morphology was investigated by scanning electron microscopy. The band gap for direct transition in CuSe2 was found to be in the range of 2.72-2.75 eV and that for indirect transition is in the range of 1.71-1.75 eV determined by UV-VIS spectroscopy. On the other hand, selenium exhibits direct band gap in the range of 2.33-2.36 eV. All estimated band gaps slightly decrease with the increase of the film thickness. Photoluminescence spectra of the thin films clearly show emission bands at about 1.63 and 2.32 eV at room temperature, with no shift observed with decreasing temperature. A model was proposed for explaining such anomaly.

Absorption and retention of selenium from shrimps in man

DEFF Research Database (Denmark)

Bugel, S. H.; Sandstrom, B.; Larsen, Erik Huusfeldt

2001-01-01

This study was undertaken to evaluate the bioavailability of selenium in shrimps, a possible good source of selenium, by measurements of the absorption and retention of selenium and the effects on plasma selenium concentration and glutathione peroxidase activity. Twelve healthy young subjects (9F...... of the study, after 2, 4, and 6 weeks. The selenium intake increased from 39.4 +/- 15.3 mug/d to 127 +/- 5.5 mug/d with the addition of shrimps. The apparent absorption of selenium from shrimps was 83 +/- 4%, Faecal and urinary selenium excretion was 32.5 +/- 17.0 mug/d and 21.2 +/- 9.0 mug/d, re spectively...... and the total retention of selenium was 3.1 +/- 1.1 mg. Plasma selenium concentrations were 95.2 +/- 9.7 mug/L and 101.5 +/- 9.7 mug/L before and after six weeks of shrimp intake, respectively (p...

Quantitative determination of selenium metabolites in human urine by LC-DRC-ICP-MS

DEFF Research Database (Denmark)

Gammelgaard, Bente; Bendahl, L.; Jacobsen, N.W.

2005-01-01

M ammonium acetate and 5% methanol with a pH of 9.25 and quantified by standard addition. Samples were collected from 8 volunteers before and after 5 days ingestion of 100 mu g Se day(-1) in form of selenized yeast. The average concentration of (SeGal-NH2) before and after selenium intake was 1.4 and 1.9 mu...... g Se L-1, respectively, while the average concentration of Se-Gal-N-Ac increased from 2.6 to 11.6 mu g Se L-1 before and after selenium consumption. Detection limits calculated on basis of three times the standard deviation on peak areas of 2 mu g Se L-1 solutions were 0.1 mu g Se L-1 for SeGal-NH2...... chromatographic system in which SeGal-NH3+ was separated from the trimethylselenonium ion. None of the samples contained TMSe+ in detectable amounts. Three sample introduction systems were compared-a microconcentric nebuliser in combination with a cyclonic spray chamber (MCN), a direct injection nebuliser (DIN...

Binary mixtures of mercury/ selenium, and lead/selenium

African Journals Online (AJOL)

Physiologically-based biokinetic models have been developed for predicting simultaneously the Absorption, Distribution, Metabolism and Elimination (ADME) properties of lead (Pb) and selenium (Se), and mercury (Hg) and selenium in a number of target tissues of humans. This was done for three population groups, ...

Flexible one-dimensional carbon-selenium composite nanofibers with superior electrochemical performance for Li-Se/Na-Se batteries

Science.gov (United States)

Zeng, Linchao; Wei, Xiang; Wang, Jiaqing; Jiang, Yu; Li, Weihan; Yu, Yan

2015-05-01

A facile strategy is developed to synthesis selenium/carbon composites (Se@CNFs-CNT) by co-heating Se powder and electrospun Polyacrylonitrile (PAN)-CNT nanofibers at 600°Cin a sealed vessel. The Se molecules are chemically bonded and physical encapsulated by carbonized PAN-CNT composite (CNFs-CNT), which leads to prevent the dissolution of polyselenide intermediates in carbonate based electrolyte. When directly used as flexible free-standing cathode material for Li-Se batteries in low cost carbonate-based electrolyte, the Se@CNFs-CNT electrode exhibits improved cyclability (517 mAh g-1 after 500 cycles at 0.5 A g-1) and rate capability (485 mAh g-1 at 1 A g-1). Moreover, when tested as sodium batteries, it maintains a reversible capacity of 410 mAh g-1 after 240 cycles at 0.5 A g-1. The superior electrochemical performance (especially at high rates) of Se@CNFs-CNT is attributed to synergistic effect of the additive of CNT, the well confine of Se in the CNFs-CNT matrix through chemical bonding and the 3D interconnected carbon nanofibers (CNFs). This simple yet efficient process thus provides a promising route towards fabrication of a variety of high performance flexible Li-Se and Na-Se batteries.

Nutrigenetics, nutrigenomics, and selenium.

Science.gov (United States)

Ferguson, Lynnette R; Karunasinghe, Nishi

2011-01-01

Selenium (Se) is an important micronutrient that, as a component of selenoproteins, influences oxidative and inflammatory processes. Its' levels vary considerably, with different ethnic and geographic population groups showing varied conditions, ranging from frank Se deficiencies to toxic effects. An optimum Se level is essential for the maintenance of homeostasis, and this optimum may vary according to life stage, general state of health, and genotype. Nutrigenetic studies of different Se levels, in the presence of genetic variants in selenoproteins, suggest that an effective dietary Se intake for one individual may be very different from that for others. However, we are just starting to learn the significance of various genes in selenoprotein pathways, functional variants in these, and how to combine such data from genes into pathways, alongside dietary intake or serum levels of Se. Advances in systems biology, genetics, and genomics technologies, including genetic/genomic, epigenetic/epigenomic, transcriptomic, proteomic, and metabolomic information, start to make it feasible to assess a comprehensive spectrum of the biological activity of Se. Such nutrigenomic approaches may prove very sensitive biomarkers of optimal Se status at the individual or population level. The premature cessation of a major human Se intervention trial has led to considerable controversy as to the value of Se supplementation at the population level. New websites provide convenient links to current information on methodologies available for nutrigenetics and nutrigenomics. These new technologies will increasingly become an essential tool in optimizing the level of Se and other micronutrients for optimal health, in individuals and in population groups. However, definitive proof of such effects will require very large collaborative studies, international agreement on study design, and innovative approaches to data analysis.

Selenium accumulation by plants.

Science.gov (United States)

White, Philip J

2016-02-01

Selenium (Se) is an essential mineral element for animals and humans, which they acquire largely from plants. The Se concentration in edible plants is determined by the Se phytoavailability in soils. Selenium is not an essential element for plants, but excessive Se can be toxic. Thus, soil Se phytoavailability determines the ecology of plants. Most plants cannot grow on seleniferous soils. Most plants that grow on seleniferous soils accumulate plant species have evolved tolerance to Se, and commonly accumulate tissue Se concentrations >100 mg Se kg(-1) dry matter. These plants are considered to be Se accumulators. Some species can even accumulate Se concentrations of 1000-15 000 mg Se kg(-1 )dry matter and are called Se hyperaccumulators. This article provides an overview of Se uptake, translocation and metabolism in plants and highlights the possible genetic basis of differences in these between and within plant species. The review focuses initially on adaptations allowing plants to tolerate large Se concentrations in their tissues and the evolutionary origin of species that hyperaccumulate Se. It then describes the variation in tissue Se concentrations between and within angiosperm species and identifies genes encoding enzymes limiting the rates of incorporation of Se into organic compounds and chromosomal loci that might enable the development of crops with greater Se concentrations in their edible portions. Finally, it discusses transgenic approaches enabling plants to tolerate greater Se concentrations in the rhizosphere and in their tissues. The trait of Se hyperaccumulation has evolved several times in separate angiosperm clades. The ability to tolerate large tissue Se concentrations is primarily related to the ability to divert Se away from the accumulation of selenocysteine and selenomethionine, which might be incorporated into non-functional proteins, through the synthesis of less toxic Se metabilites. There is potential to breed or select crops

Impact of Selenium Supplementation on Growth and Selenium Accumulation on Spinach (Spinacia oleracea L. Plants

Directory of Open Access Journals (Sweden)

Azadeh SAFFARYAZDI

2012-11-01

Full Text Available Selenium (Se has been proved to be an essential element for humans and animals. However, less is known about its effects on plants. A hydroponic experiment was carried out to investigate the effects of selenium on growth, selenium accumulation and some physiological characteristics of spinach (Spinacia oleracea L. cv. Missouri plants. Plants were grown in Hoagland nutrient solution amended with sodium selenite at 0 (control, 1, 2, 4, 6 and 10 mg.L-1 for 28 days. Growth parameters like shoot and root fresh weight, shoot and root dry weight, total dry weight, shoot and root length increased by 17, 15, 38, 19, 18 and 34 percent in response to the lowest concentration of Se (1 mg L-1, respectively over control. However, application of higher Se concentrations reduced these parameters as compared to control. Selenium up to 1 mg L-1 enhanced the levels of chlorophyll a and chlorophyll b by 87 and 165 percent, respectively, while higher levels of Se exert toxic effects. Total phenolic compounds in leaves increased directly by increasing the level of Se and plants treated with 10 mg. L-1 Se had the highest values. Selenium, sodium and calcium content increased, while potassium content decreased, by increasing selenium treatments. The highest amounts of Se in shoots (3.89 mg g-1 DW and roots (4.27 mg g-1 DW were obtained for the highest concentration of Se (10 mg L-1. The present results suggested the beneficial effects of Se on spinach growth and also its contribute ion to improving the nutritional value of spinach for livestock and human nutrition.

Impact of Selenium Supplementation on Growth and Selenium Accumulation on Spinach (Spinacia oleracea L. Plants

Directory of Open Access Journals (Sweden)

Azadeh SAFFARYAZDI

2012-11-01

Full Text Available Selenium (Se has been proved to be an essential element for humans and animals. However, less is known about its effects on plants. A hydroponic experiment was carried out to investigate the effects of selenium on growth, selenium accumulation and some physiological characteristics of spinach (Spinacia oleracea L. cv. �Missouri� plants. Plants were grown in Hoagland nutrient solution amended with sodium selenite at 0 (control, 1, 2, 4, 6 and 10 mg.L-1 for 28 days. Growth parameters like shoot and root fresh weight, shoot and root dry weight, total dry weight, shoot and root length increased by 17, 15, 38, 19, 18 and 34 percent in response to the lowest concentration of Se (1 mg L-1, respectively over control. However, application of higher Se concentrations reduced these parameters as compared to control. Selenium up to 1 mg L-1 enhanced the levels of chlorophyll a and chlorophyll b by 87 and 165 percent, respectively, while higher levels of Se exert toxic effects. Total phenolic compounds in leaves increased directly by increasing the level of Se and plants treated with 10 mg. L-1 Se had the highest values. Selenium, sodium and calcium content increased, while potassium content decreased, by increasing selenium treatments. The highest amounts of Se in shoots (3.89 mg g-1 DW and roots (4.27 mg g-1 DW were obtained for the highest concentration of Se (10 mg L-1. The present results suggested the beneficial effects of Se on spinach growth and also its contribute ion to improving the nutritional value of spinach for livestock and human nutrition.

Effect of selenium supplementation on thyroid antibodies

International Nuclear Information System (INIS)

Kvicala, J.; Hrda, P.; Zamrazil, V.; Nemecek, J.; Hill, M.; Jiranek, V.

2009-01-01

Selenium is an essential component of selenoproteins, enzymes with extensive regulatory and protective effect in organism. Immunological effects of Se are documented and are distinct even above concentrations necessary for maximal activity of selenoenzymes. Therefore, we investigated effect of supplementation by 100 μg of yeast-bound Se on concentrations of thyroid autoantibodies TPOAb and TgAb in the group of 253 seniors living in the Asylum Houses of South Bohemia. Increase of serum selenium from 59 to 150 μg Se/L serum in supplemented group and from 59 to 72 μg Se/L serum in group with placebo were detected by Instrumental Neutron Activation Analysis (INAA) and proved increased Se intake during the trial. Autoantibodies were analyzed by ELISA at the beginning of the trial and after 1 year. Statistical evaluation of results in whole groups (regardless of increased autoantibodies) by ANOVA manifested significant decrease of TPOAb and TgAb in non-supplemented group while supplementation did not effect serum autoantibodies concentrations. Evaluation of groups of seniors created from those with increased autoantibodies, ANOVA demonstrated decrease of TPOAb in both groups but Se supplementation did not affect the decrease. In opposite, TgAb increased significantly and Se supplementation led to higher increase of TgAb. Recent results of possibility to decrease serum concentration of TPOAb proved this effect only for high TPOAb concentrations and for higher Se supplements. From this point of view, it is necessary to conduct subsequent trials with the patients with autoimmune thyreoiditis with different levels of autoantibodies and detect also serum Se levels. (author)

Responses of growing Japanese quails that received selenium from selenium enriched kale sprout (Brassica oleracea var. alboglabra L.).

Science.gov (United States)

Chantiratikul, Anut; Chinrasri, Orawan; Pakmaruek, Pornpan; Chantiratikul, Piyanete; Thosaikham, Withpol; Aengwanich, Worapol

2011-12-01

The objectives of this study were to determine the effect of selenium (Se) from Se-enriched kale sprout (Brassica oleracea var. alboglabra L.) on the performance and Se concentrations in tissues of growing Japanese quails. Two hundred quails were divided into five treatments. Each treatment consisted of four replicates and each replicate contained ten quails in a completely randomize design. The experiment was conducted for 5 weeks. The treatments were T1, control diet; T2, control diet plus 0.2 mg Se/kg from sodium selenite; T3, T4, and T5, control diet plus 0.2, 0.5, and 1.0 mg Se/kg from Se-enriched kale sprout. The results revealed that Se supplementation had no impact on feed intake, performance, and carcass characteristics of quails (p > 0.05). However, Se supplementation from both sodium selenite and Se-enriched kale sprout increased (p kale sprout. The results indicate that Se from Se-enriched kale sprout offers no advantage over Se from sodium selenite on tissue Se concentration.

In vivo and in vitro testing for selenium and selenium compounds bioavailability assessment in foodstuff.

Science.gov (United States)

Moreda-Piñeiro, Jorge; Moreda-Piñeiro, Antonio; Bermejo-Barrera, Pilar

2017-03-04

The assessment of selenium and selenium species bioavailability in foodstuff is of special concern on the context of human nutrition. In vivo (human and animal), and in vitro tests are important approaches for estimating the bioavailability of toxic and essential compounds to humans. An overview on in vivo and in vitro bioavailability assays for releasing selenium and selenium species in foodstuffs is summarized. Se and Se species content in a foodstuff critically influence Se bioavailability and bioactivity to humans and animals. Se bioavailability is affected by foodstuff-matrix major composition and minor components. Foodstuffs processing and/or treatments could enhancement or decrease Se bioavailability. Experimental conditions such as the selection of healthy status of examined people (in in vivo humans approaches), the selection of animal model (in vivo animals approaches), or the selection of GI conditions (in in vitro tests) could determines the results. Thus, international standardized protocol for in vivo and in vitro approaches assessment is mandatory.

Determination of Selenium and Nickel in Asphaltite from Milli (Sirnak) Deposit in SE Anatolia of Turkey

Science.gov (United States)

Aydin, Isil; Fidan, Celal; Kavak, Orhan; Erek, Figen; Aydin, Firat

2017-12-01

Asphaltite is one of the naturally occurring black, solid bitumen’s, which are soluble at heating in carbon disulphide band fuse. Asphaltite is also a solidified hydro carbon compound derived from petroleum [1]. According to the World Energy Council, Turkish National Committee (1998), the total reserve of the asphaltic substances that are found in south eastern Turkey is about 82 million tons, with Silopi and Sirnak reserves to get her comprising the major part of the Asphaltite deposits. Selenium and Nickel are very important elements both environmental and health. Selenium plays an important role in the formation of the enzyme antioxidant effect in the cell. The need for Selenium increases in situations such as pregnancy, menopause, grow than development, air pollution. Nickel is used for preventing iron-poor blood, increasing iron absorption, and treating weak bones. In this study, asphaltites were taken from Milli vein from Sirnak deposit in SE Anatolia of Turkey. A total of 6.500.000 tons of Asphaltite reserves have been identified as asphaltites in Milli (Sirnak). The sample preparation method was developed in Asphaltite by spectroanalytical techniques, wet acid digestion. MW-AD followed by ICP-OES were used for the determination of Selenium and Nickel in Asphaltite. Proximate analysis of Asphaltite fly ash samples was made. It also, Selenium and Nickel element analysis in Asphaltite were made.

Nutrigenetics, nutrigenomics and selenium

Directory of Open Access Journals (Sweden)

Lynnette Robiin Ferguson

2011-04-01

Full Text Available Selenium (Se is an important micronutrient that, as a component of selenoproteins, influences oxidative and inflammatory processes. Its’ levels vary considerably, with different ethnic and geographic population groups showing varied conditions, ranging from frank Se deficiencies to toxic effects. An optimum Se level is essential for the maintenance of homeostasis, and this optimum may vary according to life stage, general state of health and genotype. Nutrigenetic studies of different Se levels, in the presence of genetic variants in selenoproteins, suggest that an effective dietary Se intake for one individual may be very different from that for others. However, we are just starting to learn the significance of various genes in selenoprotein pathways, functional variants in these, and how to combine such data from genes into pathways, alongside dietary intake or serum levels of Se. Advances in systems biology, genetics and genomics technologies, including genetic/genomic, epigenetic/epigenomic, transcriptomic, proteomic and metabolomic information, start to make it feasible to assess a comprehensive spectrum of the biological activity of Se. Such nutrigenomic approaches may prove very sensitive biomarkers of optimal Se status at the individual or population level. The premature cessation of a major human Se intervention trial has led to considerable controversy as to the value of Se supplementation at the population level. New websites provide convenient links to current information on methodologies available for nutrigenetics and nutrigenomics. These new technologies will increasingly become an essential tool in optimising the level of Se and other micronutrients for optimal health, in individuals and in population groups. However, definitive proof of such effects will require very large collaborative studies, international agreement on study design and innovative approaches to data analysis.

Selenium Digestibility and Bioactivity in Dogs: What the Can Can, the Kibble Can't.

Directory of Open Access Journals (Sweden)

Mariëlle van Zelst

Full Text Available There is a growing concern for the long-term health effects of selenium (Se over- or underfeeding. The efficiency of utilization of dietary Se is subject to many factors. Our study in dogs evaluated the effect of diet type (canned versus kibble and dietary protein concentration on Se digestibility and bioactivity. Canned and kibble diets are commonly used formats of dog food, widely ranging in protein concentration. Twenty-four Labrador retrievers were used and four canned and four kibble diets were selected with crude protein concentrations ranging from 10.1 to 27.5 g/MJ. Crude protein concentration had no influence on the digestibility of Se in either canned or kibble diets, but a lower Se digestibility was observed in canned compared to kibble diets. However, the biological activity of Se, as measured by whole blood glutathione peroxidase, was higher in dogs fed the canned diets than in dogs fed the kibble diets and decreased with increasing crude protein intake. These results indicate that selenium recommendations in dog foods need to take diet type into account.

Selenium Digestibility and Bioactivity in Dogs: What the Can Can, the Kibble Can't.

Science.gov (United States)

van Zelst, Mariëlle; Hesta, Myriam; Gray, Kerry; Beech, Karen; Cools, An; Alexander, Lucille G; Du Laing, Gijs; Janssens, Geert P J

2016-01-01

There is a growing concern for the long-term health effects of selenium (Se) over- or underfeeding. The efficiency of utilization of dietary Se is subject to many factors. Our study in dogs evaluated the effect of diet type (canned versus kibble) and dietary protein concentration on Se digestibility and bioactivity. Canned and kibble diets are commonly used formats of dog food, widely ranging in protein concentration. Twenty-four Labrador retrievers were used and four canned and four kibble diets were selected with crude protein concentrations ranging from 10.1 to 27.5 g/MJ. Crude protein concentration had no influence on the digestibility of Se in either canned or kibble diets, but a lower Se digestibility was observed in canned compared to kibble diets. However, the biological activity of Se, as measured by whole blood glutathione peroxidase, was higher in dogs fed the canned diets than in dogs fed the kibble diets and decreased with increasing crude protein intake. These results indicate that selenium recommendations in dog foods need to take diet type into account.

Selenium Digestibility and Bioactivity in Dogs: What the Can Can, the Kibble Can’t

Science.gov (United States)

van Zelst, Mariëlle; Hesta, Myriam; Gray, Kerry; Beech, Karen; Cools, An; Alexander, Lucille G.; Du Laing, Gijs; Janssens, Geert P. J.

2016-01-01

There is a growing concern for the long-term health effects of selenium (Se) over- or underfeeding. The efficiency of utilization of dietary Se is subject to many factors. Our study in dogs evaluated the effect of diet type (canned versus kibble) and dietary protein concentration on Se digestibility and bioactivity. Canned and kibble diets are commonly used formats of dog food, widely ranging in protein concentration. Twenty-four Labrador retrievers were used and four canned and four kibble diets were selected with crude protein concentrations ranging from 10.1 to 27.5 g/MJ. Crude protein concentration had no influence on the digestibility of Se in either canned or kibble diets, but a lower Se digestibility was observed in canned compared to kibble diets. However, the biological activity of Se, as measured by whole blood glutathione peroxidase, was higher in dogs fed the canned diets than in dogs fed the kibble diets and decreased with increasing crude protein intake. These results indicate that selenium recommendations in dog foods need to take diet type into account. PMID:27043433

EURRECA—Estimating Selenium Requirements for Deriving Dietary Reference Values

NARCIS (Netherlands)

Hurst, R.; Collings, R.; Harvey, L.J.; King, M.; Hooper, L.; Bouwman, J.; Gurinovic, M.; Fairweather-Tait, S.J.

2013-01-01

Current reference values for selenium, an essential micronutrient, are based on the intake of selenium that is required to achieve maximal glutathione peroxidase activity in plasma or erythrocytes. In order to assess the evidence of relevance to setting dietary reference values for selenium, the

Biogeochemical studies of selenium in the Indian Ocean

International Nuclear Information System (INIS)

Hattori, H.; Nakaguchi, Y.; Hiraki, K.; Kimura, M.; Koike, Y.

1999-01-01

Selenium that is a one of trace essential elements exists mainly in the chemical form of Se(IV), Se(VI) and organic selenium in ocean. Moreover, the monitoring of the selenium species has become a matter of interest as a mean of estimating their influence in biological processes in ocean. In recent works, some investigators reported that Se(IV) shows nutrient-type especially like silica's behavior, Se(VI) shows an approximately constant value, and the biological activities control the distribution of organic selenium. However, these reports were not included the whole world's oceans. It is necessary to research several oceans for the explication of fate on selenium. We investigated at the most interesting area - the Eastern Indian Ocean where should play a key role in global ocean's cycle for acquiring the new knowledge of selenium species at first

Selenium determination in biological materials by neutron activation analysis - statistical comparison between the use of 77m Se (t1/2 17.45 s) and 75 Se (t1/2 = 119,8 d)

International Nuclear Information System (INIS)

Catharino, Marilia G.M.; Vasconcelos, Marina B.A.

2002-01-01

Selenium is nowadays considered to be an essential trace element in human diet. The most extensively studied biochemical role of this element is related to its participation in the composition of glutathione peroxidase. This enzyme acts as an antioxidant for the free radicals formed in the human body. In the present work, selenium was determined by INAA in reference materials ('Human hair' IAEA-085, 'Human hair' IAEA-086, 'Dogfish Liver' DOLT-1 e 'Dogfish Muscle' DORM-1) and in toenails and vitamin supplement, using the short-lived radioisotope 77m Se. The usual method, which utilizes long- lived 75 Se, was also employed, in order to make a comparative study. A statistical test was applied for this comparison. It was verified that the average concentrations of selenium, in the reference materials and in the samples analyzed, do not differ statistically at a significance level of 0.05, which indicates the applicability of the short-lived 77m Se for INAA of the matrixes studied. (author)

Selenium accumulation in lettuce germplasm

Science.gov (United States)

Selenium (Se) is an essential micronutrient for animals and humans. Increasing Se content in food crops offers an effective approach to reduce the widespread selenium deficiency problem in many parts of the world. In this study, we evaluated thirty diverse accessions of lettuce (Lactuca sativa L.) f...

Selenium toxicity but not deficient or super-nutritional selenium status vastly alters the transcriptome in rodents

Directory of Open Access Journals (Sweden)

Sunde Roger A

2011-01-01

Full Text Available Abstract Background Protein and mRNA levels for several selenoproteins, such as glutathione peroxidase-1 (Gpx1, are down-regulated dramatically by selenium (Se deficiency. These levels in rats increase sigmoidally with increasing dietary Se and reach defined plateaus at the Se requirement, making them sensitive biomarkers for Se deficiency. These levels, however, do not further increase with super-nutritional or toxic Se status, making them ineffective for detection of high Se status. Biomarkers for high Se status are needed as super-nutritional Se intakes are associated with beneficial as well as adverse health outcomes. To characterize Se regulation of the transcriptome, we conducted 3 microarray experiments in weanling mice and rats fed Se-deficient diets supplemented with up to 5 μg Se/g diet. Results There was no effect of Se status on growth of mice fed 0 to 0.2 μg Se/g diet or rats fed 0 to 2 μg Se/g diet, but rats fed 5 μg Se/g diet showed a 23% decrease in growth and elevated plasma alanine aminotransferase activity, indicating Se toxicity. Rats fed 5 μg Se/g diet had significantly altered expression of 1193 liver transcripts, whereas mice or rats fed ≤ 2 μg Se/g diet had Conclusion This study shows that Se toxicity (5 μg Se/g diet in rats vastly alters the liver transcriptome whereas Se-deficiency or high but non-toxic Se intake elicits relatively few changes. This is the first evidence that a vastly expanded number of transcriptional changes itself can be a biomarker of Se toxicity, and that identified transcripts can be used to develop molecular biomarker panels that accurately predict super-nutritional and toxic Se status.

SeP, ApoER2 and megalin as necessary factors to maintain Se homeostasis in mammals.

Science.gov (United States)

Krol, Magdalena Beata; Gromadzinska, Jolanta; Wasowicz, Wojciech

2012-10-01

Selenoprotein P (SeP) is an extracellular protein containing ten selenium atoms in the form of selenocysteine, secreted mainly from the liver. About 60% of the whole plasma selenium level is present in SeP, which makes it a useful biomarker of selenium nutritional status. The main functions of SeP are transport and storage of selenium in plasma. It is especially an important protein for the brain, testes and kidneys where the supplementation of the proper amount of Se ensures the synthesis of selenoenzymes with antioxidant properties.Recently, it has been found that SeP uptake in kidneys, testes and brain depends on the apolipoprotein receptor 2 (ApoER2) and lipoprotein megalin receptor (Lrp2). Megalin receptor represents a physiological SeP receptor in kidneys, mediating the re-uptake of secreted SeP from the primary urine. The absence of a functional megalin receptor causes a significant reduction of plasma selenium and the SeP levels as a result of Se excretion. ApoER2 is a SeP receptor in the brain and testes which uptakes Se from the extracellular fluid. Deletion of ApoER2 in mice leads to a lowered selenium level in the brain and testes, neurological dysfunction, production of abnormal spermatozoa, infertility and even death when the subjects are fed a low-selenium diet. Copyright © 2012 Elsevier GmbH. All rights reserved.

Effect of organic selenium and zinc on the performance and egg quality of Japanese quails

Directory of Open Access Journals (Sweden)

VC Cruz

2011-06-01

Full Text Available The present study aimed at evaluating the effect of the dietary inclusion of organic trace minerals selenium and zinc on the performance and internal and external egg quality of Japanese quails submitted to heat stress. Data on egg production, feed conversion (kg feed intake/kg eggs and dozen eggs, egg weight, egg specific gravity, eggshell thickness and weight, Haugh unit, yolk index, albumen index and mortality (% of 144 quails were evaluated for 112 days, divided in eight cycles of 14 days. Birds were distributed according to a randomized block experimental design into four treatments (control; 0.3ppm Se; 60ppm Zn and 0.3ppm Se + 60ppm Zn with six replicates each. There were no differences (p> 0.05 in egg production (%, egg mass (g/hen/day, feed conversion per egg mass (kg/kg, feed conversion per dozen eggs (kg/dz, average egg weight (g, egg specific gravity, eggshell thickness and weight (g, Haugh unit, yolk index, albumen index and mortality (%. However, quails fed the combination of Se and Zn presented higher (p < 0.05 feed intake (28.73 g/hen/day. Those fed only organic selenium had higher average daily egg production (30.17 eggs/day, and those fed the diet only supplemented with zinc presented higher mortality (p < 0.05. The results of the present study suggest that the supplementation of organic trace minerals in Japanese quails diets submitted to heat stress does not significantly influence quail performance and internal egg quality, whereas the supplementation of the combination of organic Zn and Se increases feed intake.

Ecological Importance of Insects in Selenium Biogenic Cycling

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Nadezhda Golubkina

2014-01-01

Full Text Available Selenium is an essential trace element for animal and human beings. Despite the importance of insects in most ecosystems and their significant contribution to the biological cycling of trace elements due to high abundance, population productivity, and diverse ecosystem functions, surprisingly little information is available on selenium bioaccumulation by these arthropods. This review considers selenium essentiality and toxicity to insects as well as insects’ contribution to selenium trophic transfer through the food chains. Data on Se accumulation by insects of the Dniester River Valley with no anthropogenic Se loading reveal typically low Se content in necrophagous insects compared to predators and herbivores and seasonal variations in Se accumulation.

Preliminary study of daily selenium level intake in algeria

International Nuclear Information System (INIS)

Benamar, M.A.; Tchantchane, A.; Tobbeche, S.

1992-10-01

The amount of selenium in onions and potatoes was measured by Pixe (particle Induced X-ray Emission) in the Nuclear Center at Bordeaux-Gradignan (CNBG). The goal of this work is to investigate the level of selenium concentration that may be consumed by different class of people

Effect of selenium-enriched organic material amendment on selenium fraction transformation and bioavailability in soil.

Science.gov (United States)

Wang, Dan; Dinh, Quang Toan; Anh Thu, Tran Thi; Zhou, Fei; Yang, Wenxiao; Wang, Mengke; Song, Weiwei; Liang, Dongli

2018-05-01

To exploit the plant byproducts from selenium (Se) biofortification and reduce environmental risk of inorganic Se fertilizer, pot experiment was conducted in this study. The effects of Se-enriched wheat (Triticum aestivum L.) straw (WS + Se) and pak choi (Brassica chinensis L.) (P + Se) amendment on organo-selenium speciation transformation in soil and its bioavailability was evaluated by pak choi uptake. The Se contents of the cultivated pak choi in treatments amended with the same amount of Se-enriched wheat straw and pak choi were 1.7 and 9.7 times in the shoots and 2.3 and 6.3 times in the roots compared with control treatment. Soil respiration rate was significantly increased after all organic material amendment in soil (p organic materials and thus resulted in soluble Se (SOL-Se), exchangeable Se (EX-Se), and fulvic acid-bound Se (FA-Se) fraction increasing by 25.2-29.2%, 9-13.8%, and 4.92-8.28%, respectively. In addition, both Pearson correlation and cluster analysis showed that EX-Se and FA-Se were better indicators for soil Se availability in organic material amendment soils. The Marquardt-Levenberg Model well described the dynamic kinetics of FA-Se content after Se-enriched organic material amendment in soil mainly because of the mineralization of organic carbon and organo-selenium. The utilization of Se in P + Se treatment was significantly higher than those in WS + Se treatment because of the different mineralization rates and the amount of FA-Se in soil. Se-enriched organic materials amendment can not only increase the availability of selenium in soil but also avoid the waste of valuable Se source. Copyright © 2018 Elsevier Ltd. All rights reserved.

UV-photochemical vapor generation of selenium for atomic absorption spectrometry: Optimization and 75Se radiotracer efficiency study

Czech Academy of Sciences Publication Activity Database

Rybínová, M.; Musil, Stanislav; Červený, J.; Vobecký, Miloslav; Rychlovský, P.

2016-01-01

Roč. 123, SEP (2016), s. 134-142 ISSN 0584-8547 R&D Projects: GA ČR GA14-23532S Institutional support: RVO:68081715 Keywords : UV-photochemical vapor generation * Selenium * 75Se radiotracer Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 3.241, year: 2016

Why Nature Chose Selenium.

Science.gov (United States)

Reich, Hans J; Hondal, Robert J

2016-04-15

The authors were asked by the Editors of ACS Chemical Biology to write an article titled "Why Nature Chose Selenium" for the occasion of the upcoming bicentennial of the discovery of selenium by the Swedish chemist Jöns Jacob Berzelius in 1817 and styled after the famous work of Frank Westheimer on the biological chemistry of phosphate [Westheimer, F. H. (1987) Why Nature Chose Phosphates, Science 235, 1173-1178]. This work gives a history of the important discoveries of the biological processes that selenium participates in, and a point-by-point comparison of the chemistry of selenium with the atom it replaces in biology, sulfur. This analysis shows that redox chemistry is the largest chemical difference between the two chalcogens. This difference is very large for both one-electron and two-electron redox reactions. Much of this difference is due to the inability of selenium to form π bonds of all types. The outer valence electrons of selenium are also more loosely held than those of sulfur. As a result, selenium is a better nucleophile and will react with reactive oxygen species faster than sulfur, but the resulting lack of π-bond character in the Se-O bond means that the Se-oxide can be much more readily reduced in comparison to S-oxides. The combination of these properties means that replacement of sulfur with selenium in nature results in a selenium-containing biomolecule that resists permanent oxidation. Multiple examples of this gain of function behavior from the literature are discussed.

Polymer supported synthesis of unsymmetrical n.c.a. selenium-73/75 ethers for the labelling of amino acids; Polymergestuetzte Synthese von unsymmetrischen n.c.a. [{sup 73,75}Se] Selenoethern zur Markierung von Aminosaeuren

Energy Technology Data Exchange (ETDEWEB)

Schmaljohann, J

1995-09-01

The synthesis of n.c.a. selenium-73/75 labelled methionine and of a selenoalkylation agent have been performed according to a reaction including a primary, polymer supported alkylation step. The selenium-75 was produced through the {sup 75}As(p, n)-process and separated as [{sup 75}Se]selenium dioxide by thermochromatography. The [{sup 75}Se]SeO{sub 2}-sublimate was dissolved in hydrochloric acid and reduced with sulfur dioxide to obtain elemental n.c.a. selenium-75, which was extracted into benzene. Reaction of the elemental n.c.a. selenium-75 with polymeric bound triphenylphosphine led to the formation of the corresponding [{sup 75}Se]triphenylphosphinselenide in a nearly quantitative yield. The asymmetrical [{sup 75}Se]selenoethers were synthesized in homogeneous phase through the reaction of the [{sup 75}Se]MeSe{sup -} with propylhalides in radiochemical yields up of to 55%. A selenium-75 labelled prosthetic group was synthesized in radiochemical yields of 48% by the reaction of 1-chloro-3-iodopropane with the [{sup 75}]selenation reagent [{sup 75}Se]MeSe{sup -}. For labelling amino functions via [{sup 75}Se]selenoalkylation the [{sup 75}Se]selenated propyl chloride has to be transfered into the iodide with sodium iodide, which was performed in radiochemical yields of 90%. After the reaction of [{sup 75}Se]-1-iodo-3-(methylseleno)propane with butylamine or with N{sup {alpha}}-, O-protected lysine in DMF at 80 C the [{sup 75}Se]methylselenopropylated products were obtained in radiochemical yields of 95% and 90%, respectively. (orig./SR)

Bioaccumulation and toxicity of selenium compounds in the green alga Scenedesmus quadricauda

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Umysová, Dáša; Vítová, Milada; Doušková, Irena; Bišová, Kateřina; Hlavová, Monika; Čížková, Mária; Machát, Jiří; Doucha, Jiří; Zachleder, Vilém

2009-01-01

Background Selenium is a trace element performing important biological functions in many organisms including humans. It usually affects organisms in a strictly dosage-dependent manner being essential at low and toxic at higher concentrations. The impact of selenium on mammalian and land plant cells has been quite extensively studied. Information about algal cells is rare despite of the fact that they could produce selenium enriched biomass for biotechnology purposes. Results We studied the impact of selenium compounds on the green chlorococcal alga Scenedesmus quadricauda. Both the dose and chemical forms of Se were critical factors in the cellular response. Se toxicity increased in cultures grown under sulfur deficient conditions. We selected three strains of Scenedesmus quadricauda specifically resistant to high concentrations of inorganic selenium added as selenite (Na2SeO3) – strain SeIV, selenate (Na2SeO4) – strain SeVI or both – strain SeIV+VI. The total amount of Se and selenomethionine in biomass increased with increasing concentration of Se in the culturing media. The selenomethionine made up 30–40% of the total Se in biomass. In both the wild type and Se-resistant strains, the activity of thioredoxin reductase, increased rapidly in the presence of the form of selenium for which the given algal strain was not resistant. Conclusion The selenium effect on the green alga Scenedesmus quadricauda was not only dose dependent, but the chemical form of the element was also crucial. With sulfur deficiency, the selenium toxicity increases, indicating interference of Se with sulfur metabolism. The amount of selenium and SeMet in algal biomass was dependent on both the type of compound and its dose. The activity of thioredoxin reductase was affected by selenium treatment in dose-dependent and toxic-dependent manner. The findings implied that the increase in TR activity in algal cells was a stress response to selenium cytotoxicity. Our study provides a new

Bioaccumulation and toxicity of selenium compounds in the green alga Scenedesmus quadricauda

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Doucha Jiří

2009-05-01

Full Text Available Abstract Background Selenium is a trace element performing important biological functions in many organisms including humans. It usually affects organisms in a strictly dosage-dependent manner being essential at low and toxic at higher concentrations. The impact of selenium on mammalian and land plant cells has been quite extensively studied. Information about algal cells is rare despite of the fact that they could produce selenium enriched biomass for biotechnology purposes. Results We studied the impact of selenium compounds on the green chlorococcal alga Scenedesmus quadricauda. Both the dose and chemical forms of Se were critical factors in the cellular response. Se toxicity increased in cultures grown under sulfur deficient conditions. We selected three strains of Scenedesmus quadricauda specifically resistant to high concentrations of inorganic selenium added as selenite (Na2SeO3 – strain SeIV, selenate (Na2SeO4 – strain SeVI or both – strain SeIV+VI. The total amount of Se and selenomethionine in biomass increased with increasing concentration of Se in the culturing media. The selenomethionine made up 30–40% of the total Se in biomass. In both the wild type and Se-resistant strains, the activity of thioredoxin reductase, increased rapidly in the presence of the form of selenium for which the given algal strain was not resistant. Conclusion The selenium effect on the green alga Scenedesmus quadricauda was not only dose dependent, but the chemical form of the element was also crucial. With sulfur deficiency, the selenium toxicity increases, indicating interference of Se with sulfur metabolism. The amount of selenium and SeMet in algal biomass was dependent on both the type of compound and its dose. The activity of thioredoxin reductase was affected by selenium treatment in dose-dependent and toxic-dependent manner. The findings implied that the increase in TR activity in algal cells was a stress response to selenium cytotoxicity

Simultaneous tracing of 76Se-selenite and 77Se-selenomethionine by absolute labeling and speciation

International Nuclear Information System (INIS)

Suzuki, Kazuo T.; Somekawa, Layla; Kurasaki, Kazuki; Suzuki, Noriyuki

2006-01-01

Nutritional selenocompounds are transformed into the assumed common intermediate selenide, which is utilized for the synthesis of selenoenzymes or transformed into methylated metabolites for excretion. Hence, selenocompound metabolites can be traced only with labeled selenium. Here we applied a new tracer method for the metallomics of biometals using simultaneous speciation of each metallome labeled with different homo-elemental isotopes to metabolism and availability of selenium. Rats were depleted of endogenous natural abundance selenium by feeding a single selenium stable isotope ( 82 Se-selenite) and then administered 76 Se-selenite and 77 Se-selenomethionine ( 77 Se-SeMet)simultaneously. Biological samples were subjected to quantification and speciation analysis by HPLC-ICPMS. Metabolites of the labeled 76 Se and 77 Se and interaction with endogenous selenium were traced and examined without interference from the corresponding endogenous natural abundance isotopes. Differences in the distribution and metabolism among organs and between the two nutritional selenocompounds were compared under exactly identical biological and analytical conditions: (1) selenite was distributed more efficiently than SeMet in organs and body fluids except the pancreas. (2) SeMet was taken up by organs in its intact form. (3) Selenium of SeMet origin was distributed selectively in the pancreas and mostly bound to a protein together with intact SeMet. (4) Selenosugars A and B but not trimethylselenonium (TMSe) were detected in the liver. (5) Selenosugar B and TMSe were detected in the kidneys

Selenium biofortification

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Plant foods are the major dietary sources of selenium (Se) in most countries around the world, followed by meats and seafood. For this reason, it is vital to increase Se uptake by plants and to produce crops with higher Se concentrations and bioavailability in their edible tissues. One of the most p...

Review on Nano SeleniumProduced by Bacteria

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LI Ji-xiang

2014-12-01

Full Text Available Selenium (Se is a kind of essential trace element for people and animal, while ionic state of selenium is toxic with high concentrations and will cause the selenium pollution. Nano-selenium is stable, nontoxic with higher biological activity. Application of bacteria reducing selenite or selenate to biological nano-selenium has great potential in selenium pollution control and nano-selenium production. This review summarizes the research progress of the red elemental nano-selenium reduced by bacteria including characteristics and application of nano-selenium, effects of carbon and nitrogen source, oxygen, temperature and pH in bacteria nano-selenium production, and molecular mechanisms of nano-selenium reduced by bacteria.

Is selenium supplementation in autoimmune thyroid diseases justified?

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Winther, Kristian H.; Bonnema, Steen; Hegedüs, Laszlo

2017-01-01

PURPOSE OF REVIEW: This review provides an appraisal of recent evidence for or against selenium supplementation in patients with autoimmune thyroid diseases, and discusses possible effect mechanisms. RECENT FINDINGS: Epidemiological data suggest an increased prevalence of autoimmune thyroid...... diseases under conditions of low dietary selenium intake. Two systematic reviews have evaluated controlled trials among patients with autoimmune thyroiditis and report that selenium supplementation decreases circulating thyroid autoantibodies. The immunomodulatory effects of selenium might involve reducing...... proinflammatory cytokine release. However, clinically relevant effects of selenium supplementation, including improvement in quality of life, are more elusive. In Graves’ disease, some, but not all, trials indicate that adjuvant selenium supplementation enhances the restoration of biochemical euthyroidism...

Biomimetic synthesis of selenium nanospheres by bacterial strain JS-11 and its role as a biosensor for nanotoxicity assessment: a novel se-bioassay.

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Dwivedi, Sourabh; Alkhedhairy, Abdulaziz A; Ahamed, Maqusood; Musarrat, Javed

2013-01-01

Selenium nanoparticles (Se-NPs) were synthesized by green technology using the bacterial isolate Pseudomonas aeruginosa strain JS-11. The bacteria exhibited significant tolerance to selenite (SeO3(2-)) up to 100 mM concentration with an EC50 value of 140 mM. The spent medium (culture supernatant) contains the potential of reducing soluble and colorless SeO3(2-) to insoluble red elemental selenium (Se(0)) at 37°C. Characterization of red Se° product by use of UV-Vis spectroscopy, X-ray diffraction (XRD), atomic force microscopy (AFM) and transmission electron microscopy (TEM) with energy dispersive X-ray spectrum (EDX) analysis revealed the presence of stable, predominantly monodispersed and spherical selenium nanoparticles (Se-NPs) of an average size of 21 nm. Most likely, the metabolite phenazine-1-carboxylic acid (PCA) released by strain JS-11 in culture supernatant along with the known redox agents like NADH and NADH dependent reductases are responsible for biomimetic reduction of SeO3(2-) to Se° nanospheres. Based on the bioreduction of a colorless solution of SeO3(2-) to elemental red Se(0), a high throughput colorimetric bioassay (Se-Assay) was developed for parallel detection and quantification of nanoparticles (NPs) cytotoxicity in a 96 well format. Thus, it has been concluded that the reducing power of the culture supernatant of strain JS-11 could be effectively exploited for developing a simple and environmental friendly method of Se-NPs synthesis. The results elucidated that the red colored Se° nanospheres may serve as a biosensor for nanotoxicity assessment, contemplating the inhibition of SeO3(2-) bioreduction process in NPs treated bacterial cell culture supernatant, as a toxicity end point.

Does selenium supplementation affect thyroid function?

DEFF Research Database (Denmark)

Winther, Kristian Hillert; Bonnema, Steen Joop; Cold, Frederik

2015-01-01

OBJECTIVE: Selenium is present in the active site of proteins important for thyroid hormone synthesis and metabolism. The objective of this study is to investigate the effect of selenium supplementation in different doses on thyroid function, under conditions of suboptimal dietary selenium intake....... DESIGN: The Danish PREvention of Cancer by Intervention with SElenium pilot study (DK-PRECISE) is a randomized, double-blinded, placebo-controlled trial. A total of 491 males and females aged 60-74 years were randomized to 100 μg (n=124), 200 μg (n=122), or 300 μg (n=119) selenium-enriched yeast......=0.015), respectively, per 100 μg/day increase, with insignificant differences between 6 months and 5 years. No significant effects were found for FT3 and FT3:FT4 ratio. CONCLUSIONS: In euthyroid subjects, selenium supplementation minutely and dose-dependently affects thyroid function, when compared...

Selenium

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Stillings, Lisa L.; Schulz, Klaus J.; DeYoung,, John H.; Seal, Robert R.; Bradley, Dwight C.

2017-12-19

Selenium (Se) was discovered in 1817 in pyrite from copper mines in Sweden. It is a trace element in Earth’s crust, with an abundance of three to seven orders of magnitude less than the major rock-forming elements. Commercial use of selenium began in the United States in 1910, when it was used as a pigment for paints, ceramic glazes, and red glass. Since that time, it has had many other economic uses—notably, in the 1930s and 1940s, when it was used in rectifiers (which change alternating current to direct current), and in the 1960s, when it began to be used in the liner of photocopier drums. In the 21st century, other compounds have replaced selenium in these older products; modern uses for selenium include energy-efficient windows that limit heat transfer and thin-film photovoltaic cells that convert solar energy into electricity.In Earth’s crust, selenium is found as selenide minerals, selenate and selenite salts, and as substitution for sulfur in sulfide minerals. It is the sulfide minerals, most commonly those in porphyry copper deposits, that provide the bulk of the selenium produced for the international commodity market. Selenium is obtained as a byproduct of copper refining and recovered from the anode slimes generated in electrolytic production of copper. Because of this, the countries that have the largest resources and (or) reserves of copper also have the largest resources and (or) reserves of selenium.Because selenium occurs naturally in Earth’s crust, its presence in air, water, and soil results from both geologic reactions and human activity. Selenium is found concentrated naturally in soils that overlie bedrock with high selenium concentrations. Selenium mining, processing, use in industrial and agricultural applications, and disposal may all contribute selenium to the environment. A well-known case of selenium contamination from agricultural practices was discovered in 1983 in the Kesterson National Wildlife Refuge in California. There

Preparation and characterization of a laboratory scale selenomethionine-enriched bread. Selenium bioaccessibility.

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Sánchez-Martínez, María; Pérez-Corona, Teresa; Caímara, Carmen; Madrid, Yolanda

2015-01-14

This study focuses on the preparation at lab scale of selenomethionine-enriched white and wholemeal bread. Selenium was supplemented either by adding selenite directly to the dough or by using lab-made selenium-enriched yeast. The best results were obtained when using fresh selenium-enriched yeast. The optimum incubation time for selenomethionine-enriched yeast preparation, while keeping formation of selenium byproducts to a minimum, was 96 h. Selenium content measured by isotope dilution analysis (IDA)-ICP-MS in Se-white and Se-wholemeal bread was 1.28 ± 0.02 μg g–1 and 1.16 ± 0.02 μg g–1 (expressed as mean ± SE, 3 replicates), respectively. HPLC postcolumn IDA-ICP-MS measurements revealed that selenomethionine was the main Se species found in Se-enriched bread, which accounted for ca. 80% of total selenium. In vitro gastrointestinal digestion assay provided selenium bioaccessibility values of 100 ± 3% and 40 ± 1% for white and wholemeal Se-enriched bread, respectively, being selenomethionine the main bioaccessible Se species in white bread, while in wholemeal bread this compound was undetectable.

Selenium bioavailability from naturally produced high-selenium peas and oats in selenium-deficient rats.

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Yan, Lin; Johnson, LuAnn K

2011-06-08

This study determined the bioavailability of selenium (Se) from yellow peas and oats harvested from the high-Se soil of South Dakota, United States. The Se concentrations were 13.5 ± 0.2 and 2.5 ± 0.1 mg/kg (dry weight) for peas and oats, respectively. Male weanling Sprague-Dawley rats were depleted of Se by feeding them a 30% Torula yeast-based diet (4.1 μg Se/kg) for 56 days, and then they were replenished with Se for an additional 50 days by feeding them the same diet supplemented with 20, 30, or 40 μg Se/kg from peas or oats, respectively. Selenium bioavailability was determined on the basis of the restoration of Se-dependent enzyme activities and tissue Se concentrations in Se-depleted rats, comparing those responses for yellow peas and oats to those for l-selenomethionine (SeMet; used as a reference) by using a slope-ratio method. Dietary supplementation with peas or oats resulted in linear or log-linear, dose-dependent increases in glutathione peroxidase activities in blood and liver and in thioredoxin reductase activity in liver. Supplementation with peas or oats resulted in linear or log-linear, dose-dependent increases in Se concentrations of plasma, liver, gastrocnemius muscle, and kidneys. The overall bioavailability was approximately 88% for Se from yellow peas and 92% from oats, compared to SeMet. It was concluded that Se from naturally produced high-Se yellow peas or oats is highly bioavailable in this model and that these high-Se foods may be a good dietary source of Se.

Inter-individual variation of selenium in maternal plasma, cord plasma and placenta

International Nuclear Information System (INIS)

Lee, Anne M.; Huel, Guy; Godin, Jean; Hellier, Georgette; Sahuquillo, Josiane; Moreau, Thierry; Blot, Phillipe

1994-01-01

Selenium (Se) in high doses has been known to cause injury to the fetus and newborn. The major difficulty in assessing the effects of selenium on human reproduction stems from the need for a suitable means of estimating maternal and fetal exposure. The present investigation, therefore, examines the respective reliability of maternal plasma, cord plasma and placenta as epidemiological indicators as well as inter-individual variation of this trace element. An unselected population of 128 pregnancies was studied. Obstetrical characteristics were noted. Selenium concentrations were determined for maternal plasma, cord plasma, and placental tissue by fluorometric analysis. Maternal plasma selenium concentrations (Se-Bm) were significantly greater than fetal concentrations (Se-Bc). Placental selenium (Se-Pl) levels were four times that of fetal levels. Variability of Se-Bc is best explained by placental concentrations. Maternal weight and ethnic origin are significantly correlated with Se-Bc. Female newborn have higher selenium levels than male newborn. The present study demonstrates the significance of the placenta as an indicator of fetal selenium exposure

Effect of dietary selenium and omega-3 fatty acids on muscle composition and quality in broilers

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Hetland Harald

2007-10-01

Full Text Available Abstract Background Human health may be improved if dietary intakes of selenium and omega-3 fatty acids are increased. Consumption of broiler meat is increasing, and the meat content of selenium and omega-3 fatty acids are affected by the composition of broiler feed. A two-way analyses of variance was used to study the effect of feed containing omega-3 rich plant oils and selenium enriched yeast on broiler meat composition, antioxidation- and sensory parameters. Four different wheat-based dietary treatments supplemented with 5% rapeseed oil or 4% rapeseed oil plus 1% linseed oil, and either 0.50 mg selenium or 0.84 mg selenium (organic form per kg diet was fed to newly hatched broilers for 22 days. Results The different dietary treatments gave distinct different concentrations of selenium and fatty acids in thigh muscle; one percent linseed oil in the diet increased the concentration of the omega-3 fatty acids 18:3, 20:5 and 22:5, and 0.84 mg selenium per kg diet gave muscle selenium concentration at the same level as is in fish muscle (0.39 mg/kg muscle. The high selenium intake also resulted in increased concentration of the long-chain omega-3 fatty acids EPA (20:5, DPA (22:5 and DHA (22:6, thus it may be speculated if high dietary selenium might have a role in increasing the concentration of EPA, DPA and DHA in tissues after intake of plant oils contning omega-3 fatty acids. Conclusion Moderate modifications of broiler feed may give a healthier broiler meat, having increased content of selenium and omega-3 fatty acids. High intakes of selenium (organic form may increase the concentration of very long-chain omega-3 fatty acids in muscle.

Plasma Selenium Biomarkers in Low Income Black and White Americans from the Southeastern United States

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Hargreaves, Margaret K.; Liu, Jianguo; Buchowski, Maciej S.; Patel, Kushal A.; Larson, Celia O.; Schlundt, David G.; Kenerson, Donna M.; Hill, Kristina E.; Burk, Raymond F.; Blot, William J.

2014-01-01

Biomarkers of selenium are necessary for assessing selenium status in humans, since soil variation hinders estimation of selenium intake from foods. In this study, we measured the concentration of plasma selenium, selenoprotein P (SEPP1), and glutathione peroxidase (GPX3) activity and their interindividual differences in 383 low-income blacks and whites selected from a stratified random sample of adults aged 40–79 years, who were participating in a long-term cohort study in the southeastern United States (US). We assessed the utility of these biomarkers to determine differences in selenium status and their association with demographic, socio-economic, dietary, and other indicators. Dietary selenium intake was assessed using a validated food frequency questionnaire designed for the cohort, matched with region-specific food selenium content, and compared with the US Recommended Dietary Allowances (RDA) set at 55 µg/day. We found that SEPP1, a sensitive biomarker of selenium nutritional status, was significantly lower among blacks than whites (mean 4.4±1.1 vs. 4.7±1.0 mg/L, p = 0.006), with blacks less than half as likely to have highest vs. lowest quartile SEPP1 concentration (Odds Ratio (OR) 0.4, 95% Confidence Interval (CI) 0.2–0.8). The trend in a similar direction was observed for plasma selenium among blacks and whites, (mean 115±15.1 vs. 118±17.7 µg/L, p = 0.08), while GPX3 activity did not differ between blacks and whites (136±33.3 vs. 132±33.5 U/L, p = 0.320). Levels of the three biomarkers were not correlated with estimated dietary selenium intake, except for SEPP1 among 10% of participants with the lowest selenium intake (≤57 µg/day). The findings suggest that SEPP1 may be an effective biomarker of selenium status and disease risk in adults and that low selenium status may disproportionately affect black and white cohort participants. PMID:24465457

Nuclear transformations studies in selenium isotopes

International Nuclear Information System (INIS)

Lopez M, B.E.

1976-01-01

A compilation is made with regard to the chemical effects produced by nuclear transformations, such as the chemical effects of the beta decay and the chemical effects of the reaction (n,γ) in selenium radioisotopes. As a particular case the chemical effect of the isomeric transition of sup(81m)Se(VI) in potassium selenate crystals marked with radioactive selenium is studied experimentally and the method of adsorption in activated carbon is applied for the analytical separation of the traces of the nuclear isomer tetravalent sup(81b)Se(IV) of one fraction which contains the mixture of the selenium radioisotopes. (author)

Selenium and hazardous elements distribution in plant-soil-water system and human health risk assessment of Lower Cambrian, Southern Shaanxi, China.

Science.gov (United States)

Du, Yajun; Luo, Kunli; Ni, Runxiang; Hussain, Rahib

2018-03-01

The natural selenium poisoning due to toxic Se levels in food chain had been observed in humans and animals in Lower Cambrian outcrop areas in Southern Shaanxi, China. To find out the distribution pattern of selenium and other hazardous elements in the plant, soil and water of Lower Cambrian in Southern Shaanxi, China, and their possible potential health risk, a total of 30 elements were analyzed and the health risk assessment of 18 elements was calculated. Results showed that the soil, plant and natural water of Lower Cambrian all had relatively high Se levels. In Lower Cambrian, the soil was enriched with Se, As, Ba, Cu, Mo, Ni, Zn, Ga, Cd and Cr (1.68 food intake was the major pathway. For minimizing potential health risk, the local inhabitants should use the mix-imported food with local growing foods.

Selenopeptides and elemental selenium in Thunbergia alata after exposure to selenite: quantification method for elemental selenium.

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Aborode, Fatai Adigun; Raab, Andrea; Foster, Simon; Lombi, Enzo; Maher, William; Krupp, Eva M; Feldmann, Joerg

2015-07-01

Three month old Thunbergia alata were exposed for 13 days to 10 μM selenite to determine the biotransformation of selenite in their roots. Selenium in formic acid extracts (80 ± 3%) was present as selenopeptides with Se-S bonds and selenium-PC complexes (selenocysteinyl-2-3-dihydroxypropionyl-glutathione, seleno-phytochelatin2, seleno-di-glutathione). An analytical method using HPLC-ICPMS to detect and quantify elemental selenium in roots of T. alata plants using sodium sulfite to quantitatively transform elemental selenium to selenosulfate was also developed. Elemental selenium was determined as 18 ± 4% of the total selenium in the roots which was equivalent to the selenium not extracted using formic acid extraction. The results are in an agreement with the XAS measurements of the exposed roots which showed no occurrence of selenite or selenate but a mixture of selenocysteine and elemental selenium.

In vitro antioxidant and antiproliferative activities of selenium-containing phycocyanin from selenium-enriched Spirulina platensis.

Science.gov (United States)

Chen, Tianfeng; Wong, Yum-Shing

2008-06-25

Both selenium and phycocyanin have been reported to show potent cancer chemopreventive activities. In this study, we investigated the in vitro antioxidant and antiproliferative activities of selenium-containing phycocyanin (Se-PC) purified from selenium-enriched Spirulina platensis. The antioxidant activity of Se-PC was evaluated by using four different free radical scavenging assays, namely, the 2,2'-azinobis-3-ethylbenzothiazolin-6-sulfonic acid (ABTS) assay, 1,1-diphenyl-2-picryhydrazyl (DPPH) assay, superoxide anion scavenging assay, and erythrocyte hemolysis assay. The results indicated that Se-PC exhibited stronger antioxidant activity than phycocyanin by scavenging ABTS, DPPH, superoxide anion, and 2,2'-azobis-(2-amidinopropane)dihydrochloride free radicals. Se-PC also showed dose-dependent protective effects on erythrocytes against H 2O 2-induced oxidative DNA damage as evaluated by the Comet assay. Moreover, Se-PC was identified as a potent antiproliferative agent against human melanoma A375 cells and human breast adenocarcinoma MCF-7 cells. Induction of apoptosis in both A375 and MCF-7 cells by Se-PC was evidenced by accumulation of sub-G1 cell populations, DNA fragmentation, and nuclear condensation. Further investigation on intracellular mechanisms indicated that depletion of mitochondrial membrane potential (DeltaPsi m) was involved in Se-PC-induced cell apoptosis. Our findings suggest that Se-PC is a promising organic Se species with potential applications in cancer chemoprevention.

Determinants of selenium in the toenail biomonitor

International Nuclear Information System (INIS)

Morris, J.S.; Spate, V.L.; Ngwenyama, R.A.

2006-01-01

The evaluation of human nails as a measure of selenium intake and to assess selenium status in critical tissues is now being used routinely to investigate hypotheses relating selenium status to chronic disease, especially cancer. In this study we report on our observations of the major determinants of toenail selenium concentrations. Toenail specimens (3575) were, under a protocol we provided, self-collected by adult females (1940, 54.3%) and males (1635, 45.7%) living in 111 of Missouri's 114 counties. The health-conscious participants ranged in age from 18 to 94 years with means of 53.7±14.1 and 56.4±14.2 years for females and males, respectively. Selenium supplement use was over represented, 39.1% and 42.7%, and smoking was under represented, 7.5% and 7.8%, for females and males, respectively. The major determinants of toenail selenium concentration were supplement use, sex and cigarette smoking. We found no overall correlations with age, body mass index or diet selection. (author)

Comparative effect of selenium and selenium tolerant microbes on brachiaria reptans l. growth

International Nuclear Information System (INIS)

Yasin, M.; Faisal, M.

2014-01-01

Brachiaria reptans L. is an annual grass. It is good fodder grass which is distributed in tropical Asia, Kenya, Pakistan and India and introduced throughout the tropics. In present study we determine the growth correlation among B. reptans, selenium (Se) and two Se tolerant bacteria (Bacillus licheniformis-YAP7 and Bacillus cereus-YAP6). Plants treated with Se showed a significant decrease in shoot length (33%) and fresh biomass (41%) compared to control. When plants were co-cultivated in the presence of bacteria or Se and bacteria both the shoot length increased (16-34%) significantly compared to control. B. reptans plants treated with Se have shown a significant decrease in peroxidase contents (59%) compared to control. However, bacterial inoculation of Se treated plants resulted in significant increase in peroxidase contents (113-171%). Selenium treatment caused increase in leaf soluble protein contents compared to control. In conclusion, bacteria can enhance B. reptans growth under Se stress. (author)

Treating chronic arsenic toxicity with high selenium lentil diets

Energy Technology Data Exchange (ETDEWEB)

Sah, Shweta [Department of Ecosystem and Public Health, Faculty of Medicine, University of Calgary, Calgary, AB T2N 4Z6 (Canada); Vandenberg, Albert [Department of Plant Sciences, University of Saskatchewan, Saskatoon, SK S7N 5A8 (Canada); Smits, Judit, E-mail: judit.smits@ucalgary.ca [Department of Ecosystem and Public Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB T2N 4Z6 (Canada)

2013-10-01

Arsenic (As) toxicity causes serious health problems in humans, especially in the Indo-Gangetic plains and mountainous areas of China. Selenium (Se), an essential micronutrient is a potential mitigator of As toxicity due to its antioxidant and antagonistic properties. Selenium is seriously deficient in soils world-wide but is present at high, yet non-toxic levels in the great plains of North America. We evaluate the potential of dietary Se in counteracting chronic As toxicity in rats through serum biochemistry, blood glutathione levels, immunotoxicity (antibody response), liver peroxidative stress, thyroid response and As levels in tissues and excreta. To achieve this, we compare diets based on high-Se Saskatchewan (SK) lentils versus low-Se lentils from United States. Rats drank control (0 ppm As) or As (40 ppm As) water while consuming SK lentils (0.3 ppm Se) or northwestern USA lentils (< 0.01 ppm Se) diets for 14 weeks. Rats on high Se diets had higher glutathione levels regardless of As exposure, recovered antibody responses in As-exposed group, higher fecal and urinary As excretion and lower renal As residues. Selenium deficiency caused greater hepatic peroxidative damage in the As exposed animals. Thyroid hormones, triiodothyronine (T3) and thyroxine (T4), were not different. After 14 weeks of As exposure, health indicators in rats improved in response to the high Se lentil diets. Our results indicate that high Se lentils have a potential to mitigate As toxicity in laboratory mammals, which we hope will translate into benefits for As exposed humans. - Highlights: • We reduce chronic arsenic toxicity in rats with a whole food solution. • High selenium lentils decrease liver damage and increase blood glutathione levels. • High selenium lentil diets increase urinary and fecal arsenic excretion. • High selenium lentil diets decrease arsenic levels in kidney, the storage organ. • High selenium lentil diets reverse arsenic suppression of the B cell

Treating chronic arsenic toxicity with high selenium lentil diets

International Nuclear Information System (INIS)

Sah, Shweta; Vandenberg, Albert; Smits, Judit

2013-01-01

Arsenic (As) toxicity causes serious health problems in humans, especially in the Indo-Gangetic plains and mountainous areas of China. Selenium (Se), an essential micronutrient is a potential mitigator of As toxicity due to its antioxidant and antagonistic properties. Selenium is seriously deficient in soils world-wide but is present at high, yet non-toxic levels in the great plains of North America. We evaluate the potential of dietary Se in counteracting chronic As toxicity in rats through serum biochemistry, blood glutathione levels, immunotoxicity (antibody response), liver peroxidative stress, thyroid response and As levels in tissues and excreta. To achieve this, we compare diets based on high-Se Saskatchewan (SK) lentils versus low-Se lentils from United States. Rats drank control (0 ppm As) or As (40 ppm As) water while consuming SK lentils (0.3 ppm Se) or northwestern USA lentils (< 0.01 ppm Se) diets for 14 weeks. Rats on high Se diets had higher glutathione levels regardless of As exposure, recovered antibody responses in As-exposed group, higher fecal and urinary As excretion and lower renal As residues. Selenium deficiency caused greater hepatic peroxidative damage in the As exposed animals. Thyroid hormones, triiodothyronine (T3) and thyroxine (T4), were not different. After 14 weeks of As exposure, health indicators in rats improved in response to the high Se lentil diets. Our results indicate that high Se lentils have a potential to mitigate As toxicity in laboratory mammals, which we hope will translate into benefits for As exposed humans. - Highlights: • We reduce chronic arsenic toxicity in rats with a whole food solution. • High selenium lentils decrease liver damage and increase blood glutathione levels. • High selenium lentil diets increase urinary and fecal arsenic excretion. • High selenium lentil diets decrease arsenic levels in kidney, the storage organ. • High selenium lentil diets reverse arsenic suppression of the B cell

Arsenic induced clinico-hemato-pathological alterations in broilers and its attenuation by vitamin e and selenium

International Nuclear Information System (INIS)

Mashkoor, J.; Khan, A.; Khan, M.Z.; Saleemi, M.K.; Mahmood, F.

2012-01-01

Present study was carried out to know the arsenic (As) induced toxico-pathological alterations in broiler chicks and their attenuation with vitamin E (Vit E) and selenium (Se). A total of 90 day-old broiler chicks were equally distributed into 5 groups. Groups 1-4 were administered As at 50 mg/kg BW daily through feed for 30 days. In addition to A , groups 2 to 4 received Vitamin E at 150 mg/kg BW, selenium at 0.25 mg/kg BW and Vitamin E plus selenium, respectively. Group 5 (Control) received normal drinking water for 30 days. Dullness, depression, open mouth breathing, increased thirst; ruffled feathers, pale comb, skin irritation and watery diarrhea were the most striking clinical signs. The body weight and feed intake was significantly decreased in treated birds. The erythrocyte counts, hemoglobin concentration and packed cell volume decreased (P<0.05) in treated broilers with As or As with Se and Vit E. Grossly pale and hemorrhagic liver and swollen kidneys were observed in As treated birds. Arsenic treated groups showed significant decrease in serum. Histopathologically, liver exhibited congestion and cytoplasmic vacuolation. In kidneys, condensation of tubular epithelium nuclei, epithelial cell necrosis, increased urinary spaces, sloughing of tubules from basement membrane and cast deposition were observed. In conclusion As induced toxico-pathological alterations and vitamin E and selenium partially ameliorate the toxic effects in broilers chicks. (author)

The determination of Se content in Se egg by NAA in MNSR

International Nuclear Information System (INIS)

Wang Ke; Hou Xiaolin

1994-01-01

The selenium contents in the yolk, albumin and shell of the egg which was laid by layer hen fed with various Se concentrations are determined by thermal neutron activation analysis with a nuclear reaction 78 Se(n, γ) 77 Se m on the miniature neutron source reactor (MNSR). The results show that the more the selenium added to the feed, the higher the Se content in the egg and that in the egg constituents, the highest Se content is in the egg yolk and the lowest in the egg albumin

Marginal selenium deficiency down-regulates inflammation-related genes in splenic leukocytes of the mouse

NARCIS (Netherlands)

Kipp, A.P.; Banning, A.; Schothorst, van E.M.; Meplan, C.; Coort, S.L.; Evelo, C.; Keijer, J.; Hesketh, J.; Brigelius, R.

2012-01-01

Moderate selenium deficiency may lead to an impaired capacity to cope with health challenges. Functional effects of suboptimal selenium intake are not fully known, and biomarkers for an insufficient selenium supply are inadequate. We therefore fed mice diets of moderately deficient or adequate

Association between Toenail Mercury and Metabolic Syndrome Is Modified by Selenium

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Kyong Park

2016-07-01

Full Text Available Background: Although Asian populations consume relatively large amounts of fish and seafood and have a high prevalence of metabolic diseases, few studies have investigated the association between chronic mercury exposure and metabolic syndrome and its effect modification by selenium. Methods: We analyzed baseline data from the Trace Element Study of Korean Adults in the Yeungnam area. Participants included 232 men and 269 women, aged 35 years or older, who had complete data regarding demographic, lifestyle, diet, toenail mercury and selenium levels, and health. Toenail mercury and selenium concentrations were measured using instrumental neutron-activation analysis. The metabolic biomarker levels were obtained through biannual medical checkups. Results: Higher toenail mercury levels were associated with habitual consumption of whale and shark meats, older age, obesity, smoking, alcohol drinking, and higher household income. Multivariable analysis showed a positive association between toenail mercury exposure and metabolic syndrome. In addition, this association was significantly stronger at lower selenium levels and was weaker at higher selenium levels. Conclusion: The possible harmful effects of mercury on metabolic syndrome may be attenuated by high levels of selenium. Future studies are needed to suggest optimal dietary guidelines regarding fish and selenium intakes, particularly for Asians with high levels of fish intake.

Effect of selenium-saturated bovine lactoferrin (Se-bLF) on antioxidant enzyme activities in human gut epithelial cells under oxidative stress.

Science.gov (United States)

Burrow, Hannah; Kanwar, Rupinder K; Mahidhara, Ganesh; Kanwar, Jagat R

2011-10-01

Cancer and many chronic inflammatory diseases are associated with increased amounts of reactive oxygen species (ROS). The potential cellular and tissue damage created by ROS has significant impact on many disease and cancer states and natural therapeutics are becoming essential in regulating altered redox states. We have shown recently that iron content is a critical determinant in the antitumour activity of bovine milk lactoferrin (bLF). We found that 100% iron-saturated bLF (Fe-bLF) acts as a potent natural adjuvant and fortifying agent for augmenting cancer chemotherapy and thus has a broad utility in the treatment of cancer. Furthermore, we also studied the effects of iron saturated bLF's ability as an antioxidant in the human epithelial colon cancer cell line HT29, giving insights into the potential of bLF in its different states. Thus, metal saturated bLF could be implemented as anti-cancer neutraceutical. In this regard, we have recently been able to prepare a selenium (Se) saturated form of bLF, being up to 98% saturated. Therefore, the objectives of this study were to determine how oxidative stress induced by hydrogen peroxide (H2O2) alters antioxidant enzyme activity within HT29 epithelial colon cancer cells, and observe changes in this activity by treatments with different antioxidants ascorbic acid (AA), Apo (iron free)-bLF and selenium (Se)-bLF. The states of all antioxidant enzymes (glutathione peroxidase (GPx), glutathione reductase (GR), glutathione- s-transferase (GsT), catalase and superoxide dismutase (SOD)) demonstrated high levels within untreated HT29 cells compared to the majority of other treatments being used, even prior to H2O2 exposure. All enzymes showed significant alterations in activity when cells were treated with antioxidants AA, Apo-bLF or Se-bLF, with and/or without H2O2 exposure. Obvious indications that the Se content of the bLF potentially interacted with the glutathione (GSH)/GPx/GR/GsT associated redox system could be

Ethanol Consumption by Wistar Rat Dams Affects Selenium Bioavailability and Antioxidant Balance in Their Progeny

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Olimpia Carreras

2009-07-01

Full Text Available Ethanol consumption affects maternal nutrition, the mothers’ antioxidant balance and the future health of their progeny. Selenium (Se is a trace element cofactor of the enzyme glutathione peroxidase (GPx. We will study the effect of ethanol on Se bioavailability in dams and in their progeny. We have used three experimental groups of dams: control, chronic ethanol and pair-fed; and three groups of pups. Se levels were measured by graphite-furnace atomic absorption spectrometry. Serum and hepatic GPx activity was determined by spectrometry. We have concluded that ethanol decreased Se retention in dams, affecting their tissue Se deposits and those of their offspring, while also compromising their progeny’s weight and oxidation balance. These effects of ethanol are caused by a reduction in Se intake and a direct alcohol-generated oxidation action.

Evaluation of the inorganic selenium biotransformation in selenium-enriched yogurt by HPLC-ICP-MS.

Science.gov (United States)

Alzate, Adriana; Cañas, Benito; Pérez-Munguía, Sandra; Hernández-Mendoza, Hector; Pérez-Conde, Concepción; Gutiérrez, Ana Maria; Cámara, Carmen

2007-11-28

Selenium is an essential element in the human diet. Interestingly, there has been an increased consumption of dietary supplements containing this element in the form of either inorganic or organic compounds. The effect of using selenium as a dietary supplement in yogurt has been evaluated. For this purpose, different concentrations of inorganic Se (ranging from 0.2 to 5000 microg g(-1)) have been added to milk before the fermentation process. Biotransformation of inorganic Se into organic species has been carefully evaluated by ion-exchange, reversed-phase, or size-exclusion chromatography, coupled to inductively coupled plasma mass spectrometry (ICP-MS). Yogurt fermentation in the presence of up to 2 microg g(-1) of Se(IV) produces a complete incorporation of this element into proteins as has been demonstrated applying a dialysis procedure. Analysis by SEC-ICP-MS showed that most of them have a molecular mass in the range of 30-70 kDa. Species determination after enzymatic hydrolysis has allowed the identification of Se-cystine using two different chromatographic systems. The biotransformation process that takes place during yogurt fermentation is very attractive because yogurt can act as a source of selenium supplementation.

Mechanism of Selenium Loss in Copper Slag

Science.gov (United States)

Desai, Bhavin; Tathavadkar, Vilas; Basu, Somnath

2018-03-01

During smelting of copper sulfide concentrate, selenium is distributed between silica-saturated iron-silicate slag and copper-iron sulfide matte. The recovery coefficients of selenium between slag and matte were determined as a function of the initial concentration of selenium at 1523 K (1250 °C) under an inert atmosphere in a vertical tubular furnace. The initial concentration of selenium was varied by the addition of metallic selenium as well as selenium dioxide to the mixture of slag and matte. Analysis of the results indicated high affinity of selenium for matte. The apparent loss of selenium with the slag was attributed to the presence of selenium-enriched matte particles entrapped in the slag, rather than dissolved SeO2. The mechanisms proposed by previous investigators were discussed and also compared with the results of the present investigation.

Mechanism of Selenium Loss in Copper Slag

Science.gov (United States)

Desai, Bhavin; Tathavadkar, Vilas; Basu, Somnath

2018-06-01

During smelting of copper sulfide concentrate, selenium is distributed between silica-saturated iron-silicate slag and copper-iron sulfide matte. The recovery coefficients of selenium between slag and matte were determined as a function of the initial concentration of selenium at 1523 K (1250 °C) under an inert atmosphere in a vertical tubular furnace. The initial concentration of selenium was varied by the addition of metallic selenium as well as selenium dioxide to the mixture of slag and matte. Analysis of the results indicated high affinity of selenium for matte. The apparent loss of selenium with the slag was attributed to the presence of selenium-enriched matte particles entrapped in the slag, rather than dissolved SeO2. The mechanisms proposed by previous investigators were discussed and also compared with the results of the present investigation.

Assessment of selenium bioavailability from naturally produced high-selenium soy foods in selenium-deficient rats.

Science.gov (United States)

Yan, Lin; Reeves, Philip G; Johnson, LuAnn K

2010-10-01

We assessed the bioavailability of selenium (Se) from a protein isolate and tofu (bean curd) prepared from naturally produced high-Se soybeans. The Se concentrations of the soybeans, the protein isolate and tofu were 5.2±0.2, 11.4±0.1 and 7.4±0.1mg/kg, respectively. Male weanling Sprague-Dawley rats were depleted of Se by feeding them a 30% Torula yeast-based diet (4.1μg Se/kg) for 56 days, and then they were replenished with Se for an additional 50 days by feeding them the same diet containing 14, 24 or 30 μg Se/kg from the protein isolate or 13, 23 or 31 μg Se/kg from tofu, respectively. l-Selenomethionine (SeMet) was used as a reference. Selenium bioavailability was determined on the basis of the restoration of Se-dependent enzyme activities and tissue Se concentrations in Se-depleted rats, comparing those responses for the protein isolate and tofu to those for SeMet by using a slope-ratio method. Dietary supplementation with the protein isolate or tofu resulted in linear or log-linear, dose-dependent increases in glutathione peroxidase activities in blood and liver and in thioredoxin reductase activity in liver. Furthermore, supplementation with the protein isolate or tofu resulted in linear or log-linear, dose-dependent increases in the Se concentrations of plasma, liver, muscle and kidneys. These results indicated an overall bioavailability of approximately 101% for Se from the protein isolate and 94% from tofu, relative to SeMet. We conclude that Se from naturally produced high-Se soybeans is highly bioavailable in this model and that high-Se soybeans may be a good dietary source of Se. Published by Elsevier GmbH.

Is selenium supplementation in autoimmune thyroid diseases justified?

Science.gov (United States)

Winther, Kristian H; Bonnema, Steen J; Hegedüs, Laszlo

2017-10-01

This review provides an appraisal of recent evidence for or against selenium supplementation in patients with autoimmune thyroid diseases, and discusses possible effect mechanisms. Epidemiological data suggest an increased prevalence of autoimmune thyroid diseases under conditions of low dietary selenium intake. Two systematic reviews have evaluated controlled trials among patients with autoimmune thyroiditis and report that selenium supplementation decreases circulating thyroid autoantibodies. The immunomodulatory effects of selenium might involve reducing proinflammatory cytokine release. However, clinically relevant effects of selenium supplementation, including improvement in quality of life, are more elusive. In Graves' disease, some, but not all, trials indicate that adjuvant selenium supplementation enhances the restoration of biochemical euthyroidism, and might benefit patients with mild Graves' orbitopathy. The use of selenium supplementation as adjuvant therapy to standard thyroid medication may be widespread, but a growing body of evidence yields equivocal results. The available evidence from trials does not support routine selenium supplementation in the standard treatment of patients with autoimmune thyroiditis or Graves' disease. However, correction of moderate to severe selenium deficiency may offer benefits in preventing, as well as treating, these disorders. Molecular mechanisms have been proposed, but further studies are needed.

Impact of Selenium Supplementation on Growth and Selenium Accumulation on Spinach (Spinacia oleracea L.) Plants

OpenAIRE

Azadeh SAFFARYAZDI; Mehrdad LAHOUTI; Ali GANJEALI; Hassan BAYAT

2012-01-01

Selenium (Se) has been proved to be an essential element for humans and animals. However, less is known about its effects on plants. A hydroponic experiment was carried out to investigate the effects of selenium on growth, selenium accumulation and some physiological characteristics of spinach (Spinacia oleracea L. cv. �Missouri�) plants. Plants were grown in Hoagland nutrient solution amended with sodium selenite at 0 (control), 1, 2, 4, 6 and 10 mg.L-1 for 28 days. Growth parameters like sh...

The influence of selenium and deiodinases blockers on juvenile rats body weight

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Milanović Svetlana

2014-01-01

Full Text Available In this work there was investigated the influence of selenium and deodinases blockers on juvenile rats body weight during three months. The experiment was carried out on 64 rats divided into eight groups with eight individual animals per group. Following groups were formed: 1. Se+PTU-IA- (control group, 2. Se+PTU+IA+, 3. Se+PTU+IA-, 4. Se+PTU- IA+, 5. Se-PTU-IA-, 6. Se-PTU+IA+, 7. Se-PTU+IA- and 8. Se-PTU-IA+. The groups labeled (Se+ were selenium adequate and they were fed with food that contained 0.334 mg Se/kg. The groups labeled (Se- were selenium deficient and obtained food with 0.031 mg Se/kg. As deiodinases blockers there were used propylthiouracil (PTU+ in a dose of 150 mg/L of drinking water and iopanoic acid (IA+ in a dose of 6 mg/100 g TM intraperitoneally. Body weight of experimental rats was measured every seven days. After three weeks of treatment there were taken blood samples of animals from all experimental groups and following parameters were determined: selenium concentration in blood, thyroxine (T4, triiodothyronine (T3 and thyroidstimulating hormone (TSH in blood plasma. Analysis of the samples showed that the animals from the groups treated with PTU had lower body weight in regard to the control group, as well as lower concentration of T3 and T4 in plasma. Selenium deficient rats had lower average body weight compared to the selenium adequate ones after three weeks, but there were no differences in thyroid hormones concentration. The lowest average body weight was noticed in selenium deficient rats groups treated with PTU. [Projekat Ministartsva nauke Republike Srbije, br. TR31050 i br. TR31003

Selenium accumulation and metabolism in algae.

Science.gov (United States)

Schiavon, Michela; Ertani, Andrea; Parrasia, Sofia; Vecchia, Francesca Dalla

2017-08-01

Selenium (Se) is an intriguing element because it is metabolically required by a variety of organisms, but it may induce toxicity at high doses. Algae primarily absorb selenium in the form of selenate or selenite using mechanisms similar to those reported in plants. However, while Se is needed by several species of microalgae, the essentiality of this element for plants has not been established yet. The study of Se uptake and accumulation strategies in micro- and macro-algae is of pivotal importance, as they represent potential vectors for Se movement in aquatic environments and Se at high levels may affect their growth causing a reduction in primary production. Some microalgae exhibit the capacity of efficiently converting Se to less harmful volatile compounds as a strategy to cope with Se toxicity. Therefore, they play a crucial role in Se-cycling through the ecosystem. On the other side, micro- or macro-algae enriched in Se may be used in Se biofortification programs aimed to improve Se content in human diet via supplementation of valuable food. Indeed, some organic forms of selenium (selenomethionine and methylselenocysteine) are known to act as anticarcinogenic compounds and exert a broad spectrum of beneficial effects in humans and other mammals. Here, we want to give an overview of the developments in the current understanding of Se uptake, accumulation and metabolism in algae, discussing potential ecotoxicological implications and nutritional aspects. Copyright © 2017 Elsevier B.V. All rights reserved.

Selenium speciation and isotope composition in 77Se-enriched yeast using gradient elution HPLC separation and ICP-dynamic reaction cell-MS

DEFF Research Database (Denmark)

Larsen, Erik Huusfeldt; Sloth, Jens Jørgen; Hansen, M.

2003-01-01

using the enriched Se-77-selenite as substrate, were released by enzymatic hydrolysis using (I), a beta-glucosidase followed by a protease mixture, and (II), a commercial protease preparation. For selenium speciation the chromatographic selectivity of the cation exchange HPLC system was adjusted...

Removal of Selenium and Nitrate in Groundwater Using Organic Carbon-Based Reactive Mixtures

Science.gov (United States)

An, Hyeonsil; Jeen, Sung-Wook

2016-04-01

Treatment of selenium and nitrate in groundwater was evaluated through column experiments. Four columns consisting of reactive mixtures, either organic carbon-limestone (OC-LS) or organic carbon-zero valent iron (OC-ZVI), were used to determine the removal efficiency of selenium with different concentrations of nitrate. The source waters were collected from a mine site in Korea or were prepared artificially based on the mine drainage water or deionized water, followed by spiking of elevated concentrations of Se (40 mg/L) and nitrate (100 or 10 mg/L as NO3-N). The results for the aqueous chemistry showed that selenium and nitrate were effectively removed both in the mine drainage water and deionized water-based artificial input solution. However, the removal of selenium was delayed when selenium and nitrate coexisted in the OC-LS columns. The removal of selenium was not significant when the influent nitrate concentration was 100 mg/L as NO3-N, while most of nitrate was gradually removed within the columns. In contrast, 94% of selenium was removed when the influent nitrate concentration was reduced to 10 mg/L as NO3-N. In the OC-ZVI column, selenium and nitrate was removed almost simultaneously and completely even with the high nitrate concentration; however, a high concentration of ammonia was produced as a by-product of abiotic reaction between ZVI and nitrate. The elemental analysis for the solid samples after the termination of the experiments showed that selenium was accumulated in the reactive materials where removal of aqueous-phase selenium mostly occurred. The X-ray absorption near-edge structure (XANES) study indicated that selenium existed in the forms of SeS2 and Se(0) in the OC-LS column, while selenium was present in the forms of FeSe, SeS2 and absorbed Se(IV) in the OC-ZVI column. This study shows that OC-based reactive mixtures have an ability to remove selenium and nitrate in groundwater. However, the removal of selenium was influenced by the high

Effect of foliar application of selenium on its uptake and speciation in carrot

DEFF Research Database (Denmark)

Kápolna, Emese; Hillestrøm, Peter René; Laursen, K.H.

2009-01-01

Carrot (Daucus carota) shoots were enriched by selenium using foliar application. Solutions of sodium selenite or sodium selenate at 10 and 100 mu g Se ml(-1), were sprayed on the carrot leaves and the selenium content and uptake rate of selenium were estimated by ICP-MS analysis. Anion and cation......(-1) (dry mass) in the carrot root whereas the selenium concentration in the controls was below the limit of detection at 0.045 mu g Se g(-1) (dry mass). Selenate-enriched carrot leaves accumulated as much as 80 mu g Se g(-1) (dry mass), while the selenite-enriched leaves contained approximately 50 mu...... g Se g(-1) (dry mass). The speciation analyses showed that inorganic selenium was present in both roots and leaves. The predominant metabolised organic forms of selenium in the roots were selenomethionine and gamma-glutamyl-selenomethyl-selenocysteine, regardless of which of the inorganic species...

Selenium contents of Japanese foodstuffs by neutron activation analysis

International Nuclear Information System (INIS)

Noda, Katsuhiko; Hirai, Shoji; Danbara, Hiroshi.

1980-01-01

Selenium (Se) contents of Japanese foodstuffs were measured by neutron activation analyses with the TRIGA-II reactor in Atomic Energy Research Laboratory, Musashi Institute of Technology. Freezedried samples (200 - 500 mg) were irradiated in the pneumatic tube (thermal neutron flux, 1 x 10 12 n.cm -2 . sec -1 ) for 10 sec, and sup(77m)Se produced was counted for 30 sec in a gamma -ray spectrometer system equipped with a Ge(Li) detector. Samples containing less than 0.05 ppm Se and the processed foods of high salt contents were analyzed with radioactivities of 75 Se after irradiation in the central symble (thermal neutron flux, 4 x 10 12 n.cm -2 .sec -1 ) for 5 hours, digestion in the HNO 3 -HClO 4 mixture, and then purification by a precipitation process. Foodstuffs of animal origins contained more Se than those of plant origins. Se contents were as follows in the descending order: fish, meats, cereals, vegetables, and fruit. Daily per capital intaked of Se was in the range of 100 - 200 mu g, as calculated for and as found by analysis of composite diets representing ordinary Japanese meals. (author)

Activation analysis of selenium in odorous vegetable foods

International Nuclear Information System (INIS)

Suzuki, Shogo; Hirai, Shoji; Noda, Katsuhiko.

1981-01-01

The selenium in odorous vegetables was analyzed by nondestructive neutron activation analysis using 75 Se, by the γ-ray coincidence method with a Ge(Li) and a NaI(Tl) detectors of definite energy ranges. By means of the coincidence counting, the background spectrum in 75 Se in the vicinity of 265 KeV was able to be reduced to about 1/20 of that by the former detector alone, so that the 75 Se detection sensitivity was raised over fourfold. Thus the selenium in odorous vegetables was able to be determined down to the content as low as 0.02 μg/g. The selenium content in garlic bulbs was 0.02 - 0.31 μg/g, and in onion bulbs 0.02 - 0.05 μg/g, both of which agreed well with those by fluorometry. In other odorous vegetables, the selenium content was as little as 0.1 μg/g or lower. It has been said that the selenium content is relatively large along with sulfur because of the same group, but it was found to be fairly small in the odorous vegetables. (Mori, K.)

Synthesis and biodistribution of 75Se-dinonyl-diselenide

International Nuclear Information System (INIS)

Liu, Y.F.; Qian, H.Q.; Zhang, Q.X.; Wang, X.Y.; Sun, J.G.; Li, B.Z.; Zhang, W.J.

1985-01-01

Selenium-75-labelled dinonyl-diselenide, C 9 H 19 75 SeSeC 9 H 19 , was synthesized and identified. It was injected into white rats in order to observe the selenium distribution in the tissues using inorganic 75 SeO 2 as the control agent. The sequence order of the 75 Se-dinonyl-diselenide uptake by tissues was: pancreas, muscles, stomach, liver, kidneys, spleen, blood, lungs, heart, brain, eyes. A very high accumulation of 75 Se-dinonyl-diselenide in the pancreas was observed, similar to that of the pancreatic imaging agent 75 Se-methionine. Furthermore, the enzymatic activity of glutathione peroxidase in the case of organic diselenide injection was higher than that measured for selenite. Selenium of dinonyl-diselenide was more effective and retainable in the process of converting itself to selenium-containing enzyme via the metabolic reactions. It may be advisable to replace inorganic sodium selenite by organic selenium compounds. Sodium selenite has been widely used in the prevention of the Keshan disease in China. (author)

Biotransformation and accumulation of selenium inside organisms in an engineered aquatic ecosystem designed for bioremediation of Se from agriculture drainage water and brine shrimp production

Science.gov (United States)

Excessive selenium (Se) in soils and waters present in the westside of central California was determined to be responsible for ecotoxicities observed in water fowl frequenting large bodies of water, i.e., evaporation ponds. In order to monitor the fate and potentially design an aquatic Se remediatio...

Histopathological changes due to the effect of selenium in experimental cockerels

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S.A.A Latheef

2014-01-01

Full Text Available Background & objectives: Selenium usually acts as an antioxidant at optimal levels in the body and increased levels are toxic. In this study an attempt was made to evaluate the effect of an optimum dose (0.14 mg of selenium on histopathological changes in experimental hypercholesterolemia in cockerels. Methods: The effect of selenium (0.14 mg was investigated on histopathological changes in four tissues namely liver, kidney, heart, and descending aorta in cockerel animal model. Animals were either fed with stock diet (group C, stock diet with cholesterol (group CH, stock diet with selenium (group Se, stock diet, selenium and cholesterol (group CH+Se for six months. Animals were sacrified and the tissues were isolated and subjected to histopathological study. Results: Xanthochromatic collections in liver were observed in group CH; hydropic degeneration in group Se and lobular disarray, hydropic degeneration and kuppfer cell hyperplasia in group CH+Se were observed. In kidney, mild mononuclear infiltration was observed in interstitium in groups CH, Se and CH+Se. myocyte disruption, and mononuclear infiltration in group CH and c0 H+Se, and disruption of muscle bundles with vascular congestion in group Se were observed. Smooth muscle proliferation in the media of blood vessel was observed in groups CH, Se and CH+Se. Interpretation & conclusions: The results of the present study suggested that the optimum dose of (140 ΅g/day feeding induced atherogenesis by inflammation and smooth muscle proliferation in cockerels with experimentally induced hypercholesterolaemia.

Selenium and breast cancer risk: A prospective nested case-control study on serum selenium levels, smoking habits and overweight.

Science.gov (United States)

Sandsveden, Malte; Manjer, Jonas

2017-11-01

Previous research has not been conclusive regarding the association between selenium (Se) and breast cancer. This study was conducted to clarify if there is an association between prediagnostic serum Se levels and breast cancer risk. A population based cohort, the Malmö Diet and Cancer Study, was used and linked with the Swedish cancer registry up to 31 December 2013. Our study included 1,186 women with breast cancer and an equal number of controls. Selenium levels were analysed from stored serum samples. The included individuals were divided into quartiles based on Se value and we compared breast cancer cases with controls using logistic regression yielding odds ratios (OR) with 95% confidence intervals. Serum Se was also analysed as a continuous variable regarding breast cancer risk. The analyses were adjusted for established risk factors and stratified on smoking status and body mass index (BMI). When comparing the highest Se quartile with the lowest, the adjusted OR for breast cancer was 0.98 (0.75-1.26). With selenium as a continuous variable the adjusted OR was 1.00 (1.00-1.01) per 10 ng/ml. When comparing the highest with the lowest Se quartile in women with BMI > 25 kg/m 2 the adjusted OR was 0.77 (0.53-1.14). We conclude that it is unlikely that prediagnostic serum selenium is overall associated with breast cancer risk and no modifying effect from BMI or smoking was seen. © 2017 UICC.

Selenium Cycling Across Soil-Plant-Atmosphere Interfaces: A Critical Review

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Lenny H.E. Winkel

2015-05-01

Full Text Available Selenium (Se is an essential element for humans and animals, which occurs ubiquitously in the environment. It is present in trace amounts in both organic and inorganic forms in marine and freshwater systems, soils, biomass and in the atmosphere. Low Se levels in certain terrestrial environments have resulted in Se deficiency in humans, while elevated Se levels in waters and soils can be toxic and result in the death of aquatic wildlife and other animals. Human dietary Se intake is largely governed by Se concentrations in plants, which are controlled by root uptake of Se as a function of soil Se concentrations, speciation and bioavailability. In addition, plants and microorganisms can biomethylate Se, which can result in a loss of Se to the atmosphere. The mobilization of Se across soil-plant-atmosphere interfaces is thus of crucial importance for human Se status. This review gives an overview of current knowledge on Se cycling with a specific focus on soil-plant-atmosphere interfaces. Sources, speciation and mobility of Se in soils and plants will be discussed as well as Se hyperaccumulation by plants, biofortification and biomethylation. Future research on Se cycling in the environment is essential to minimize the adverse health effects associated with unsafe environmental Se levels.

Mercury and selenium in European catfish (Silurus glanis) from Northern Italian Rivers: can molar ratio be a predictive factor for mercury toxicity in a top predator?

Science.gov (United States)

Squadrone, S; Benedetto, A; Brizio, P; Prearo, M; Abete, M C

2015-01-01

The study of mercury and selenium bioaccumulation in fish is crucially important for evaluating the extent of contamination in freshwater environments, and the possible health risk posed for humans when the antagonistic interactions of these two elements are considered. Several factors affect the risk of mercury intake from fish consumption, including mercury levels, human consumption patterns, and sensitive populations (e.g., pregnant women, foetuses, young children and unknown genetic factors). The protective effects of selenium on mercury toxicity have been extensively publicised in recent years, particularly targeting fish consumers. In this study, mercury (Hg) and selenium (Se) concentrations were determined in the muscle of European catfish (Silurus glanis) collected from North Italian Rivers. Differences in mercury and selenium levels, as a function of size, gender and location were investigated. Hg was strongly related to length, gender and location, while Se levels are not dependent on fish size or location. The mean Se/Hg molar ratio was strongly affected by location, and significantly related to length and age. Selenium was in molar excess of mercury in all sites, with a rank order of mean Se/Hg molar ratio of the Parma River (2.55)>Po River (1.71)>Tanaro River (1.66)>Bormida River (1.36). However, in 37% of analyzed samples, Hg exceeded the maximum level set by 1881/2006/EC and 629/2008/EC in fish muscle. The molar ratio of Se/Hg was 0.5mg/kg), and therefore the mean molar ratio cannot be considered as a safety criterion in top predator fish. Copyright © 2014 Elsevier Ltd. All rights reserved.

Mercury and selenium in fishes from the Tapajós River in the Brazilian Amazon: An evaluation of human exposure.

Science.gov (United States)

Lino, A S; Kasper, D; Guida, Y S; Thomaz, J R; Malm, O

2018-07-01

This work aimed to evaluate associated risks of fish consumption to human health, concerning mercury (Hg) and selenium (Se) concentrations in fish species largely consumed in the Tapajós River basin in the Brazilian Amazon. Total mercury (THg), methylmercury (MeHg) and Se concentrations were measured in 129 fish specimens from four sites of the Tapajós River basin. Estimated daily intake (EDI) of Hg and Se were reported regarding fish consumption. EDI were compared with the reference value of provisional tolerable daily intake proposed by the World Health Organization (WHO). Se:Hg ratios and selenium health benefit values (Se HBVs) seem to offer a more comprehensive fish safety model. THg concentrations in fishes ranged from 0.03 to 1.51 μg g -1 of wet weight (w.w.) and MeHg concentrations ranged from 0.02 to 1.44 μg g -1 (w.w.). 80% of the samples were below the value of Hg recommended by the WHO for human consumption (0.5 μg g -1 w.w.). However, Hg EDI exceeded the dose suggested by the United States Environmental Protection Agency (0.1 μg kg -1  day -1 ), due to the large level of fish consumption in that area. Se concentrations in fishes ranged from 0.02 to 0.44 μg g -1 w.w. An inverse pattern was observed between Hg and Se concentrations in the trophic chain (highest levels of Se in the lowest trophic levels). The molar ratio Se:Hg and Se HBVs were higher in iliophagous and herbivorous fishes, which is noteworthy to reduce toxic effects of Hg contamination. For planktivores, the content of Se and Hg was almost equimolar. Carnivorous fishes - with the exception of Hemisorubim platyrhynchos and Pseudoplatystoma fasciatum -, showed Se:Hg ratios <1. Thus, they do not act as a favorable source of Se in the diet. Therefore, reduced intake of carnivorous fishes with preferential consumption of iliophages, herbivores and, to some extent, even planktivores should be promoted as part of a healthier diet. Copyright © 2018 Elsevier GmbH. All

Thioacetamide-induced cirrhosis in selenium-adequate mice displays rapid and persistent abnormity of hepatic selenoenzymes which are mute to selenium supplementation

International Nuclear Information System (INIS)

Zhang Jinsong; Wang Huali; Yu Hanqing

2007-01-01

Selenium reduction in cirrhosis is frequently reported. The known beneficial effect of selenium supplementation on cirrhosis is probably obtained from nutritionally selenium-deficient subjects. Whether selenium supplementation truly improves cirrhosis in general needs additional experimental investigation. Thioacetamide was used to induce cirrhosis in selenium-adequate and -deficient mice. Selenoenzyme activity and selenium content were measured and the influence of selenium supplementation was evaluated. In Se-adequate mice, thioacetamide-mediated rapid onset of hepatic oxidative stress resulted in an increase in thioredoxin reductase activity and a decrease in both glutathione peroxidase activity and selenium content. The inverse activity of selenoenzymes (i.e. TrxR activity goes up and GPx activity goes down) was persistent and mute to selenium supplementation during the progress of cirrhosis; accordingly, cirrhosis was not improved by selenium supplementation in any period. On the other hand, selenium supplementation to selenium-deficient mice always more efficiently increased hepatic glutathione peroxidase activity and selenium content compared with those treated with thioacetamide, indicating that thioacetamide impairs the liver bioavailability of selenium. Although thioacetamide profoundly affects hepatic selenium status in selenium-adequate mice, selenium supplementation does not modify the changes. Selenium supplementation to cirrhotic subjects with a background of nutritional selenium deficiency can improve selenium status but cannot restore hepatic glutathione peroxidase and selenium to normal levels

Selenium recovery from kiln powder of cement manufacturing by chemical leaching and bioreduction.

Science.gov (United States)

Soda, S; Hasegawa, A; Kuroda, M; Hanada, A; Yamashita, M; Ike, M

2015-01-01

A novel process by using chemical leaching followed by bacterial reductive precipitation was proposed for selenium recovery from kiln powder as a byproduct of cement manufacturing. The kiln powder at a slurry concentration of 10 w/v% with 0.25 M Na2CO3 at 28°C produced wastewater containing about 30 mg-Se/L selenium. The wastewater was diluted four-fold and adjusted to pH 8.0 as preconditioning for bioreduction. A bacterial strain Pseudomonas stutzeri NT-I, capable of reducing selenate and selenite into insoluble elemental selenium, could recover about 90% selenium from the preconditioned wastewater containing selenium of 5 mg-Se/L when supplemented with lactate or glycerol. The selenium concentrations in the treated wastewater were low around the regulated effluent concentration of 0.1 mg-Se/L in Japan.

Se metallomics during lactic fermentation of Se-enriched yogurt.

Science.gov (United States)

Palomo, María; Gutiérrez, Ana M; Pérez-Conde, M Concepción; Cámara, Carmen; Madrid, Yolanda

2014-12-01

Selenium biotransformation by lactic acid bacteria during the preparation of Se-enriched yogurt was evaluated. The study focused on the distribution of selenium in the aqueous soluble protein fraction and the detection of selenoamino acids. Screening of selenium in Tris-buffer-urea soluble fraction was carried out by sodium dodecyl sulphate polyacrylamide gel electrophoresis after pre-fractionating with asymmetric field flow fractionation using inductively coupled plasma-mass spectrometry as the detector. Selenium-containing fractions were identified by peptide mapping using nano LC-ESI/LTQMS. Proteins such as thioredoxin, glutaredoxin, albumin, β-lactoglobulin, and lactoperoxidase were identified in the selenium-containing fraction. All these proteins were detected in both the control and the selenium-enriched yogurt except chaperones, which were only detected in the control samples. Chaperones are heat-shock proteins expressed in response to elevated temperature or other cellular stresses. Selenium may have an effect on chaperones expression in Lactobacillus. For the amino acids analysis, selenocysteine was the primary seleno-containing species. Copyright © 2014 Elsevier Ltd. All rights reserved.

Determination of selenium via the fluorescence quenching effect of selenium on hemoglobin-catalyzed peroxidative reaction.

Science.gov (United States)

Chen, Ya-Hong; Zhang, Ya-Nan; Tian, Feng-Shou

2015-05-01

A new method for the determination of selenium based on its fluorescence quenching on the hemoglobin-catalyzed reaction of H2 O2 and l-tyrosine has been established. The effect of pH, foreign ions and the optimization of variables on the determination of selenium was examined. The calibration curve was found to be linear between the fluorescence quenching (F0 /F) and the concentration of selenium within the range of 0.16-4.00 µg/mL. The detection limit was 1.96 ng/mL and the relative standard deviation was 3.14%. This method can be used for the determination of selenium in Se-enriched garlic bulbs with satisfactory results. Copyright © 2014 John Wiley & Sons, Ltd.

Toxicological implications of selenium nanoparticles with different coatings along with Se4+ on Lemna minor.

Science.gov (United States)

Tarrahi, Roshanak; Khataee, Alireza; Movafeghi, Ali; Rezanejad, Farkhondeh; Gohari, Gholamreza

2017-08-01

Nanoparticles have potential high risks for living organisms in the environment due to their specific qualities and their easy access. In the present study, selenium nanoparticles (Se NPs) with two different coatings (l-cysteine and tannic acid) were synthesized. The characteristics of particles were analyzed using XRD, FT-IR and SEM. The impact of the nanoparticles besides Se 4+ , on the aquatic higher plant Lemna minor was evaluated and compared. Entrance of l-cysteine and tannic acid capped Se NPs in the roots of Lemna minor was proved by TEM and fluorescence microscopy. Adverse effects of mentioned NPs and differences of these effects from those by sodium selenite as the ionic form were assessed by a range of biophysicochemical tests. Altogether, the results asserted that Lemna minor was notably poisoned by both capped Se NPs and Se 4+ . Thus, growth and photosynthetic pigments were decreased while lipid peroxidation along with total phenol and flavonoid contents were raised. Eventually some changes in enzymatic activities were presented. To sum up the consequences, it can be concluded that all changes occurred due to the plant defense system especially in order to remove reactive oxygen species (ROS) and possible phytotoxicity originated by l- cysteine and tannic acid capped Se NPs in addition to Se 4+ . The influence of tannic acid capped Se NPs after sodium selenite is stronger by the means of antioxidant enzymes activity in comparison with l-cysteine capped Se NPs. Copyright © 2017 Elsevier Ltd. All rights reserved.

Nutrigenetics, Nutrigenomics, and Selenium

OpenAIRE

Ferguson, Lynnette R.; Karunasinghe, Nishi

2011-01-01

Selenium (Se) is an important micronutrient that, as a component of selenoproteins, influences oxidative and inflammatory processes. Its’ levels vary considerably, with different ethnic and geographic population groups showing varied conditions, ranging from frank Se deficiencies to toxic effects. An optimum Se level is essential for the maintenance of homeostasis, and this optimum may vary according to life stage, general state of health, and genotype. Nutrigenetic studies of different Se le...

Investigation of the selenium metabolism in cancer cell lines

DEFF Research Database (Denmark)

Lunøe, Kristoffer; Gabel-Jensen, Charlotte; Stürup, Stefan

2011-01-01

The aim of this work was to compare different selenium species for their ability to induce cell death in different cancer cell lines, while investigating the underlying chemistry by speciation analysis. A prostate cancer cell line (PC-3), a colon cancer cell line (HT-29) and a leukaemia cell line...... (Jurkat E6-1) were incubated with five selenium compounds representing inorganic as well as organic Se compounds in different oxidation states. Selenomethionine (SeMet), Se-methylselenocysteine (MeSeCys), methylseleninic acid (MeSeA), selenite and selenate in the concentration range 5-100 mu M were...... incubated with cells for 24 h and the induction of cell death was measured using flow cytometry. The amounts of total selenium in cell medium, cell lysate and the insoluble fractions was determined by ICP-MS. Speciation analysis of cellular fractions was performed by reversed phase, anion exchange and size...

Nuclear-based methods for the study of selenium

International Nuclear Information System (INIS)

Spyrou, N.M.; Akanle, O.A.; Dhani, A.

1988-01-01

The essentiality of selenium to the human being and in particular its deficiency state, associated with prolonged inadequate dietary intake, have received considerable attention. In addition, the possible relationship between selenium and cancer and the claim that selenium may possess cancer-prevention properties have focused research effort. It has been observed in a number of studies on laboratory animals that selenium supplementation protects the animals against carcinogen-induced neoplastic growth in various organ sites, reduces the incidence of spontaneous mammary tumors, and suppresses the growth of transplanted tumor cells. In these research programs on the relationship between trace element levels and senile dementia and depression and the elemental changes in blood associated with selenium supplementation in a normal group of volunteers, it became obvious that in addition to establishing normal levels of elements in the population of interest, there was a more fundamental requirement for methods to be developed that would allow the study of the distribution of selenium in the body and its binding sites. The authors propose emission tomography and perturbed angular correlation as techniques worth exploring

Selenium as an essential micronutrient: roles in cell cycle and apoptosis.

Science.gov (United States)

Zeng, Huawei

2009-03-23

Selenium is an essential trace element for humans and animals, and selenium deficiency is associated with several disease conditions such as immune impairment. In addition, selenium intakes that are greater than the recommended daily allowance (RDA) appear to protect against certain types of cancers. In humans and animals, cell proliferation and death must be regulated to maintain tissue homeostasis, and it has been well documented that numerous human diseases are directly related to the control of cell cycle progression and apoptosis. Thus, the elucidation of the mechanisms by which selenium regulates the cell cycle and apoptosis can lead to a better understanding of the nature of selenium's essentiality and its role in disease prevention. This article reviews the status of knowledge concerning the effect of selenium on cell cycle and apoptosis.

Supplementation with Selenium and Coenzyme Q10 Reduces Cardiovascular Mortality in Elderly with Low Selenium Status. A Secondary Analysis of a Randomised Clinical Trial

Science.gov (United States)

Alexander, Jan; Aaseth, Jan

2016-01-01

Background Selenium is needed by all living cells in order to ensure the optimal function of several enzyme systems. However, the selenium content in the soil in Europe is generally low. Previous reports indicate that a dietary supplement of selenium could reduce cardiovascular disease but mainly in populations in low selenium areas. The objective of this secondary analysis of a previous randomised double-blind placebo-controlled trial from our group was to determine whether the effects on cardiovascular mortality of supplementation with a fixed dose of selenium and coenzyme Q10 combined during a four-year intervention were dependent on the basal level of selenium. Methods In 668 healthy elderly individuals from a municipality in Sweden, serum selenium concentration was measured. Of these, 219 individuals received daily supplementation with selenium (200 μg Se as selenized yeast) and coenzyme Q10 (200 mg) combined for four years. The remaining participants (n = 449) received either placebo (n = 222) or no treatment (n = 227). All cardiovascular mortality was registered. No participant was lost during a median follow-up of 5.2 years. Based on death certificates and autopsy results, all mortality was registered. Findings The mean serum selenium concentration among participants at baseline was low, 67.1 μg/L. Based on the distribution of selenium concentration at baseline, the supplemented group was divided into three groups; 85 μg/L (45 and 90 percentiles) and the remaining participants were distributed accordingly. Among the non-treated participants, lower cardiovascular mortality was found in the high selenium group as compared with the low selenium group (13.0% vs. 24.1%; P = 0.04). In the group with the lowest selenium basal concentration, those receiving placebo or no supplementation had a mortality of 24.1%, while mortality was 12.1% in the group receiving the active substance, which was an absolute risk reduction of 12%. In the middle selenium concentration

Molecular neutron activation analysis of selenium metabolites in urine

International Nuclear Information System (INIS)

Blotcky, A.J.; Hansen, G.T.; Ebrahim, A.; Rack, E.P.

1988-01-01

Because of the biological importance of selenium in living biological systems, various analytical procedures have been developed for analysis of microquantities of elemental selenium, in urine, serum, and tissue. For urine selenium, these include atomic absorption spectrometry, solution absorption spectrometry, solution fluorescence spectrometry, volumetry, and neutron activation analysis. Of equal or greater importance is the determination of selenium metabolites present in urine for the purpose of describing the biological pathways for the metabolism of selenium in living organisms. While it is known from previous studies that trimethylselenonium ion (TMSe) is a major metabolite in urine, probably the result of reduction and methylation reaction, there are no definitive results in the literature indicating the nature or quantity of other selenium metabolic products in urine. Early techniques to measure TMSe levels in urine involved the use of the radiotracer 75 Se. Because of the long biological half-life of selenium and issues of radiation exposure, its use in humans has been limited. In this paper, the authors report the experimental procedure for the determination of total selenoamino acid concentration in urine and present total selenium values, and, where applicable, TMSe, SeO 2- 3 , and total selenoamino acid concentrations in the urine of normal and diseased subjects

Growth and fruit body formation of Pleurotus ostreatus on media supplemented with inorganic selenium

Directory of Open Access Journals (Sweden)

Savić Milena D.

2009-01-01

Full Text Available Selenium is a trace mineral chemically related to sulfur and tellurium. In the body selenium combines with protein molecules to form selenoproteins and it is distributed in low concentrations and unequally in air, soil and water all over the world. Edible mushrooms are known to be selenium accumulators. Since mushrooms contain relatively high protein levels, and they can accumulate large amounts of selenium, it is reasonable to expect that selenium could be incorporated into proteins. The growth of mycelia and fruit body formation of different medicinal mushroom strains of Pleurotus ostreatus (Hk-35 and P70 over the wide range of concentrations of inorganic form of selenium were examined. Mushrooms were cultivated on agar base media and on substrates based on sawdust. Vegetative growths of mycelium were measured as colony diameter in pure cultures supplemented with inorganic form of Se supplements, prepared as Na2SeO4 and Na2SeO3 in concentrations of: 1, 10, 25, 50, 75, 100 and 150 mg/l. Inorganic form of Se supplements, showed stimulation effects (in concentration of 1-50 mg/l and toxic effects in higher concentration. On the standard industrial sawdust based substrate, supplemented with 100 mg/kg Na2SeO4 and Na2SeO3, accumulation of Se in fruit bodies was determined by the method of flameless atomic absorption spectrophotometer. The readings were performed on Varian SpectrAA-10 spectrophotometer equipped with VGA-76. Se as Na2SeO4 and Na2SeO3 was effectively taken up from substrates and accumulated in fruit bodies. Mushrooms accumulated selenium between 120 and 250 mg/kg dry weight. In mushrooms cultivated without Se supplement, Se contents were only about 1 mg/kg and in substrate about 0.1 mg/kg.

Elevated levels of selenium in the typical diet of Amazonian riverside populations

Energy Technology Data Exchange (ETDEWEB)

Lemire, Melanie, E-mail: lemire.melanie@courrier.uqam.ca [Centre de recherche interdisciplinaire sur la biologie, la sante, la societe et l' environnement (CINBIOSE), Universite du Quebec a Montreal, Montreal (Canada); Fillion, Myriam [Centre de recherche interdisciplinaire sur la biologie, la sante, la societe et l' environnement (CINBIOSE), Universite du Quebec a Montreal, Montreal (Canada); Barbosa, Fernando [Depto. de Analises Clinicas, Toxicologicas e Bromatologicas, Universidade de Sao Paulo, Ribeirao Preto (Brazil); Guimaraes, Jean Remy Davee [Instituto de Biofisica, Universidade Federal do Rio de Janeiro, Rio de Janeiro (Brazil); Mergler, Donna [Centre de recherche interdisciplinaire sur la biologie, la sante, la societe et l' environnement (CINBIOSE), Universite du Quebec a Montreal, Montreal (Canada)

2010-09-01

Selenium (Se) intake is generally from food, whose Se content depends on soil Se and plant accumulation. For humans, adequate Se intake is essential for several selenoenzymes. In the Lower Tapajos region of the Brazilian Amazon, Se status is elevated with large inter-community variability. Se intake in this region, where Hg exposure is among the highest in the world, may be important to counteract mercury (Hg) toxicity. The present study was conducted in 2006 with 155 persons from four communities of the Lower Tapajos. The objectives were: i) to evaluate Se content in their typical diet and drinking water; ii) to compare food Se concentrations with respect to geographic location; and iii) to examine the contribution of consumption of different food items to blood Se. More than 400 local foods and 40 drinking water samples were collected. Participants responded to an interview-administered food frequency questionnaire and provided blood samples. Food, water and blood Se levels were assessed by ICP-MS. Since Brazil nuts may also contain significant levels of barium (Ba) and strontium (Sr), these elements were likewise analyzed in nuts. The highest Se concentrations were found in Brazil nuts, but concentrations were highly variable (median: 13.9 {mu}g/g; range: 0.4-158.4 {mu}g/g). Chicken, game meat, eggs and beef also contained considerable levels of Se, with median concentrations from 0.3 to 1.4 {mu}g/g. There was no particular geographic distribution of food Se. Se concentration in drinking water was very low (< 1.4 {mu}g/L). Blood Se covered a (103-1500 {mu}g/L), and was positively related to regular consumption of Brazil nuts, domestic chicken and game meat. Brazil nuts were found to contain highly variable and often very high concentrations of Ba (88.0 {mu}g/g, 1.9-1437 {mu}g/g) and Sr (38.7 {mu}g/g, 3.3-173 {mu}g/g). Further studies should address multiple nutrient/toxic interactions in the diet and related effects on health.

Elevated levels of selenium in the typical diet of Amazonian riverside populations

International Nuclear Information System (INIS)

Lemire, Melanie; Fillion, Myriam; Barbosa, Fernando; Guimaraes, Jean Remy Davee; Mergler, Donna

2010-01-01

Selenium (Se) intake is generally from food, whose Se content depends on soil Se and plant accumulation. For humans, adequate Se intake is essential for several selenoenzymes. In the Lower Tapajos region of the Brazilian Amazon, Se status is elevated with large inter-community variability. Se intake in this region, where Hg exposure is among the highest in the world, may be important to counteract mercury (Hg) toxicity. The present study was conducted in 2006 with 155 persons from four communities of the Lower Tapajos. The objectives were: i) to evaluate Se content in their typical diet and drinking water; ii) to compare food Se concentrations with respect to geographic location; and iii) to examine the contribution of consumption of different food items to blood Se. More than 400 local foods and 40 drinking water samples were collected. Participants responded to an interview-administered food frequency questionnaire and provided blood samples. Food, water and blood Se levels were assessed by ICP-MS. Since Brazil nuts may also contain significant levels of barium (Ba) and strontium (Sr), these elements were likewise analyzed in nuts. The highest Se concentrations were found in Brazil nuts, but concentrations were highly variable (median: 13.9 μg/g; range: 0.4-158.4 μg/g). Chicken, game meat, eggs and beef also contained considerable levels of Se, with median concentrations from 0.3 to 1.4 μg/g. There was no particular geographic distribution of food Se. Se concentration in drinking water was very low (< 1.4 μg/L). Blood Se covered a (103-1500 μg/L), and was positively related to regular consumption of Brazil nuts, domestic chicken and game meat. Brazil nuts were found to contain highly variable and often very high concentrations of Ba (88.0 μg/g, 1.9-1437 μg/g) and Sr (38.7 μg/g, 3.3-173 μg/g). Further studies should address multiple nutrient/toxic interactions in the diet and related effects on health.

Novel selenium-doped hydroxyapatite coatings for biomedical applications.

Science.gov (United States)

Rodríguez-Valencia, C; López-Álvarez, M; Cochón-Cores, B; Pereiro, I; Serra, J; González, P

2013-03-01

Nowadays there is a short-term need of investigating in orthopedic implants with a greater functionality, including an improved osseointegration and also antibacterial properties. The coating of metallic implants with hydroxyapatite (HA) remains to be the main proposal, but superior quality HA coatings with compositions closer to natural bone apatites, including carbonates, trace elements are required. Selenium is an essential nutrient in biological tissues and, at the same time, it also presents antibacterial properties. A pioneering study on the fabrication of selenium-doped carbonated hydroxyapatite (iHA:Se) coatings by Pulsed Laser Deposition (PLD) is presented. Different proportions of selenium were incorporated to obtain the iHA:Se coatings. Their physicochemical characterization, performed by SEM/EDS, FTIR, FT-Raman, Interferometric Profilometry and XPS, revealed typical columnar growth of HA in globular aggregates and the efficient incorporation of selenium into the HA coatings by the, most probably, substitution of SeO(3)(2-) groups in the CO(3)(2-) sites. Biological evaluation illustrated the absence of cytotoxicity when an amount of 0.6 at.% of Se was added to the iHA:Se coatings and excellent proliferation of the MC3T3-E1 preosteoblasts. Antibacterial properties were also proved with the inhibition of P. aeruginosa and S. aureus from establishing bacterial biofilms. Copyright © 2012 Wiley Periodicals, Inc.

Effect of Gamma Radiation on The Microbial Production of Selenium Nanoparticles

International Nuclear Information System (INIS)

El Zahaby, D.A.T.M.

2014-01-01

Selenium is a trace element commonly found in materials of the earth's crust. Selenium is well known for its photoelectric, semiconductor, free-radical scavenging (HUANG et al., 2003), anti-oxidant(El-Batal et al., 2012 a) and anti-cancer properties(El-Batal et al., 2012 b ; El-Batal et al., 2012 c; Mansour et al., 2010; Zhang et al., 2004). Selenium occurs in different forms as red amorphous selenium (Se"0), highly water soluble selenate(SeO_4"2"-) and Selenite(SeO_3"2"-), and as gaseous selenide(Se"2"-). Amongst its various forms, the SeO_3"2"- is highly toxic, which adversely affect the cellular respiration and antioxidant system causes protein inactivation and DNA repair inhibition (Dong et al., 2003; Eustice et al., 1981; Turner et al., 1998). Therefore, detoxification of SeO_3"2"- has attracted a great deal of attention, particularly the reduction of this oxy anion by the microorganisms(Dwivedi et al., 2013). Most methods used to synthesize selenium nanoparticles (SeNPs) are physical and chemical methods, they are characterized by elevated temperatures, long growth times, high pressures, low yields and are also environmentally hazardous (Li et al., 2007). There is an interesting and exciting biogenic synthesis to prepare SeNPs, the synthesis of SeNPs by biological systems occurs at close to ambient temperatures and pressures and at neutral ph(Bharde et al., 2006). This method is a clean, nontoxic and environmentally friendly procedure. In addition, biological synthesis can present extra advantages over chemical methods such as higher productivity and lower cost (Parikh et al., 2008). Attempts have been made to synthesize SeNPs from such microorganisms as bacteria, fungi (Zare et al., 2013) and yeast (Hariharan et al., 2012). However, a bacterial system is preferred mainly due to reduced time of reaction, ease in handling, and easy genetic manipulation (Wang et al., 2010). The majority of studies on the biogenesis of SeNPs have focused on anaerobic systems

Shape coexistence in selenium isotopes

International Nuclear Information System (INIS)

Liu Ying; Cao Zhongbin; Xu Furong

2010-01-01

Nuclear shape change and shape coexistence in the Selenium isotopes have been investigated by Total-Routhian-Surface (TRS) calculations. It is found that nuclear shapes vary significantly with increasing neutron number. The TRS calculations for the ground states of 66,72,92,94 Se isotopes show that both neutron-deficient and neutron-dripline Selenium isotopes have oblate and prolate shape coexistence. The cranking shell-model calculations for 72,94 Se give that prolate and oblate shape coexistence in low rotational frequency. However, oblate rotational bands disappear and prolate rotational bands become yrast bands with increasing rotational frequency, which is due to the intrusion of the g 9/2 orbitals. (authors)

Hypercholesterolemia and apolipoprotein B expression: Regulation by selenium status

Directory of Open Access Journals (Sweden)

Bansal Mohinder P

2005-11-01

Full Text Available Abstract Background Apolipoprotein B (apoB contains ligand-binding domain for the binding of LDL to LDL-R site, which enables the removal of LDL from circulation. Our recent data showed that selenium (Se is involved in the lipid metabolism. The present study was aimed to understand the effect of Se deficiency (0.02 ppm and selenium supplementation (1 ppm on apoB expression in liver during hypercholesterolemia in male Sprague Dawley rats. Animals were fed with control and high cholesterol diet (2% for 1 and 2 months. ApoB levels by ELISA and protein expression by western blot was done. Hepatic LDL receptor (LDL-R activity (in vivo and mRNA expression by RT-PCR was monitored. Results In selenium deficiency and on high cholesterol diet (HCD feeding apoB levels increased and LDL-R expression decreased significantly after 2 months. On 1 ppm selenium supplementation apoB expression significantly decreased and LDL-R expression increased after 2 months. But after one month of treatment there was no significant change observed in apoB and LDL-R expression. Conclusion So the present study demonstrates that Se deficiency leads to up regulation of apoB expression during experimental hypercholesterolemia. Selenium supplementation upto 1 ppm leads to downregulation of apoB expression. Further, this study will highlight the nutritional value of Se supplementation in lipid metabolism.

Toxicity and oxidative stress of different forms of organic selenium (Se) and dietary protein in mallard (Anas platyrhynchos) ducklings

Science.gov (United States)

Hoffman, D.; Heinz, G.; Eisemann, J.; Pendleton, G.

1994-01-01

High concentrations of Se have been found in aquatic food chains associated with irrigation drainwater and toxicity to fish and wildlife. Earlier studies have compared toxicities of Se as selenite and as seleno-DL-methionine (DL) in mallards. This study compares DL, seleno-L-methionine (L), selenized yeast (Y) and selenized wheat (W). Day-old mallard ducklings received an untreated diet (controls) containing 75% wheat (22% protein) or the same diet containing 15 or 30 ppm Se in the above forms. After 2 weeks blood and liver samples were collected for biochemical assays and Se analysis. All forms of selenium caused significant increases in plasma and hepatic glutathione peroxidase activities. Se as L was the most toxic, resulting in high mortality (64%) and impaired growth (>50%) and the greatest increase in ratio of oxidized to reduced glutathione with 30 ppm in the diet. Se as Y accumulated the least in liver. In a subsequent experiment with 30% dietary protein Se as L was less toxic.

Synthesis of 75Se-2-phenyl-1,2-benzisoselenazol-3(2H)-one (PZ 51; Ebselen). A novel biologically active organo-selenium compound

International Nuclear Information System (INIS)

Cantineau, R.; Tihange, G.; Plenevaux, A.; Christiaens, L.; Guillaume, M.; Welter, A.; Dereu, N.

1986-01-01

The preparation of 75 Se-ebselen ( 75 Se-PZ 51) in a high radiochemical yield (approx. 40%) and with a specific activity of 240 mCi/mM (8.9 GBq/mM) is described. It entails a very simple, fast and one-pot procedure starting from elemental 75 Se-selenium. 75 Se-diselenosalicylic acid is initially prepared as the key intermediate which is transformed into a corresponding dichloride before reacting with aniline to yield the desired 75 Se-ebselen. Identity and purity of the labelled compound were controlled by comparison in TLC, HPLC and MS with an authentic sample. (author)

Selenium and Its Supplementation in Cardiovascular Disease—What do We Know?

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Carina Benstoem

2015-04-01

Full Text Available The trace element selenium is of high importance for many of the body’s regulatory and metabolic functions. Balanced selenium levels are essential, whereas dysregulation can cause harm. A rapidly increasing number of studies characterizes the wide range of selenium dependent functions in the human body and elucidates the complex and multiple physiological and pathophysiological interactions of selenium and selenoproteins. For the majority of selenium dependent enzymes, several biological functions have already been identified, like regulation of the inflammatory response, antioxidant properties and the proliferation/differentiation of immune cells. Although the potential role of selenium in the development and progression of cardiovascular disease has been investigated for decades, both observational and interventional studies of selenium supplementation remain inconclusive and are considered in this review. This review covers current knowledge of the role of selenium and selenoproteins in the human body and its functional role in the cardiovascular system. The relationships between selenium intake/status and various health outcomes, in particular cardiomyopathy, myocardial ischemia/infarction and reperfusion injury are reviewed. We describe, in depth, selenium as a biomarker in coronary heart disease and highlight the significance of selenium supplementation for patients undergoing cardiac surgery.

Selenium and Its Supplementation in Cardiovascular Disease—What do We Know?

Science.gov (United States)

Benstoem, Carina; Goetzenich, Andreas; Kraemer, Sandra; Borosch, Sebastian; Manzanares, William; Hardy, Gil; Stoppe, Christian

2015-01-01

The trace element selenium is of high importance for many of the body’s regulatory and metabolic functions. Balanced selenium levels are essential, whereas dysregulation can cause harm. A rapidly increasing number of studies characterizes the wide range of selenium dependent functions in the human body and elucidates the complex and multiple physiological and pathophysiological interactions of selenium and selenoproteins. For the majority of selenium dependent enzymes, several biological functions have already been identified, like regulation of the inflammatory response, antioxidant properties and the proliferation/differentiation of immune cells. Although the potential role of selenium in the development and progression of cardiovascular disease has been investigated for decades, both observational and interventional studies of selenium supplementation remain inconclusive and are considered in this review. This review covers current knowledge of the role of selenium and selenoproteins in the human body and its functional role in the cardiovascular system. The relationships between selenium intake/status and various health outcomes, in particular cardiomyopathy, myocardial ischemia/infarction and reperfusion injury are reviewed. We describe, in depth, selenium as a biomarker in coronary heart disease and highlight the significance of selenium supplementation for patients undergoing cardiac surgery. PMID:25923656

Selenium hyperaccumulation - Astragalus bisulcatus, Cardamine hupingshanensis and Stanleya pinnata - may be useful for agromining selenium-rich soils

Science.gov (United States)

Selenium hyperaccumulator plants like Stanleya pinnata, Astragalus bisulcatus and the newly discovered Se-accumulator Cardamine hupingshanensis may play an important role in the Se cycle from soil to plant to human in China. Se-hyperaccumulators can be used for agromining or for phytoremediation of ...

Selenium deficiency risk predicted to increase under future climate change.

Science.gov (United States)

Jones, Gerrad D; Droz, Boris; Greve, Peter; Gottschalk, Pia; Poffet, Deyan; McGrath, Steve P; Seneviratne, Sonia I; Smith, Pete; Winkel, Lenny H E

2017-03-14

Deficiencies of micronutrients, including essential trace elements, affect up to 3 billion people worldwide. The dietary availability of trace elements is determined largely by their soil concentrations. Until now, the mechanisms governing soil concentrations have been evaluated in small-scale studies, which identify soil physicochemical properties as governing variables. However, global concentrations of trace elements and the factors controlling their distributions are virtually unknown. We used 33,241 soil data points to model recent (1980-1999) global distributions of Selenium (Se), an essential trace element that is required for humans. Worldwide, up to one in seven people have been estimated to have low dietary Se intake. Contrary to small-scale studies, soil Se concentrations were dominated by climate-soil interactions. Using moderate climate-change scenarios for 2080-2099, we predicted that changes in climate and soil organic carbon content will lead to overall decreased soil Se concentrations, particularly in agricultural areas; these decreases could increase the prevalence of Se deficiency. The importance of climate-soil interactions to Se distributions suggests that other trace elements with similar retention mechanisms will be similarly affected by climate change.

Binding and Conversion of Selenium in Candida utilis ATCC 9950 Yeasts in Bioreactor Culture

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Marek Kieliszek

2017-02-01

Full Text Available Selenium is considered an essential component of all living organisms. The use of yeasts as a selenium supplement in human nutrition has gained much interest over the last decade. The accumulation and biochemical transformation of selenium in yeast cells is particularly interesting to many researchers. In this article, we present the results of the determination of selenium and selenomethionine content in the biomass of feed yeast Candida utilis ATCC 9950 obtained from the culture grown in a bioreactor. The results indicated that C. utilis cells performed the biotransformation of inorganic selenium(IV to organic derivatives (e.g., selenomethionine. Selenium introduced (20–30 mg Se4+∙L−1 to the experimental media in the form of sodium(IV selenite (Na2SeO3 salt caused a significant increase in selenium content in the biomass of C. utilis,irrespective of the concentration. The highest amount of selenium (1841 μg∙gd.w.−1 was obtained after a 48-h culture in media containing 30 mg Se4+∙L−1. The highest content of selenomethionine (238.8 μg∙gd.w.−1 was found after 48-h culture from the experimental medium that was supplemented with selenium at a concentration of 20 mg Se4+∙L−1. Biomass cell in the cultures supplemented with selenium ranged from 1.5 to 14.1 g∙L−1. The results of this study indicate that yeast cell biomass of C. utilis enriched mainly with the organic forms of selenium can be a valuable source of protein. It creates the possibility of obtaining selenium biocomplexes that can be used in the production of protein-selenium dietary supplements for animals and humans

Evaluación de la exposición a selenio en Los Altos de Jalisco, México Evaluation of the exposure to selenium in Los Altos de Jalisco, México

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Roberto Hurtado-Jiménez

2007-08-01

Full Text Available OBJETIVO: Evaluar la exposición a selenio (Se vía agua potable en los habitantes de Los Altos de Jalisco. MATERIAL Y MÉTODOS: Se determinó la concentración de Se en 125 pozos y se estimaron los niveles de exposición a Se en bebés, niños y adultos. RESULTADOS: La dosis de exposición y la ingestión de Se vía agua potable variaron en los siguientes rangos: a bebés: 1.3-6.7 µg/kg/d y 12.6-67.2 µg/d; b niños: 0.8-4.5 µg/kg/d y 16.8-89.6 µg/d; c adultos: 0.6-3.0 µg/kg/d y 33.6-179.2 µg/d. CONCLUSIONES: En este caso, la exposición a Se representa un riesgo potencial para la salud de la población, ya que en la mayoría de los casos es mayor que la recomendada por organismos internacionales de salud. Sin embargo, no es tan alta como para esperar la ocurrencia de selenosis.OBJECTIVE: To evaluate the exposure to selenium in drinking water in Los Altos de Jalisco (Jalisco State Heights. MATERIALS AND METHODS: The concentration of selenium was determined in 125 water wells, and the exposure doses to selenium were estimated for babies, children and adults. RESULTS: The estimated values of the exposure doses to selenium and total intake of selenium were in the following ranges, respectively: (a babies: 1.3-6.7 µg/kg/d and 12.6-67.2 µg/d; (b children: 0.8-4.5 µg/kg/d and 16.8-89.6 µg/d, (c adults: 0.6-3.0 µg/kg/d and 33.6-179.2 µg/d. CONCLUSIONS: The estimated exposure levels to selenium were higher than those recommended as optimum by international health organizations, representing a potential health risk. Nevertheless, estimated values are not high enough to produce selenosis.

Status of selenium in cancer prevention

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An abundance of data indicate that selenium (Se) can be antitumorigenic. Those data, mostly from controlled studies using animal tumor models and some from clinical studies in free-living people, indicate that treatment with Se in the absence of nutritional Se-deficiency, can reduce cancer risk. T...

Chemopreventive effects of PBI-Se, a selenium-containing analog of PBIT, on AOM-induced aberrant crypt foci in F344 rats.

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Janakiram, Naveena B; Mohammed, Altaf; Ravillah, Durgadevi; Choi, Chang In; Zhang, Yuting; Desai, Dhimant; Amin, Shantu; Rao, Chinthalapally V

2013-08-01

Inducible nitric oxide synthase (iNOS) is a potential target for the treatment of inflammation and cancer. Previously, we showed that the selective iNOS inhibitor S,S'-1,4-phenylenebis(1,2-ethanediyl)bis-isothiourea (PBIT) caused significant inhibition of colon carcinogenesis induced by azoxymethane (AOM), although it did not completely abrogate NO production due to the exogenous bioavailability of NO and NO generation by eNOS in tumor tissues. To create an iNOS-targeting molecule that may have additional benefits, a novel isosteric analog of PBIT, PBI-Se, was developed, in which sulfur was replaced with selenium. Chemopreventive efficacy of PBI-Se was evaluated in an AOM-induced rat colon carcinogenesis model using aberrant crypt foci (ACF) as the endpoint. At 7 weeks of age, rats (12/group) were fed the control diet (AIN 76A) and then colonic ACF were induced with two AOM treatments. Three days later, rats were fed diets containing PBI-Se (0-20 ppm) for 8 weeks, and then ACF were evaluated histopathologically. Dietary administration of 10 or 20 ppm of PBI-Se significantly suppressed AOM-induced total colonic ACF formation (32 or 41%, pPBI-Se was dose-dependent and was half the dose of PBIT for inhibiting total ACF in rats. Both PBIT and PBI-Se induced dose-dependent apoptosis in CaCo2 cells and caused a significant decrease in the cell cycle proteins cyclin D1 (70%, pPBI-Se (2 and 4  µM) significantly decreased the LPS-induced cytokine interleukin-6 level. Incorporation of selenium into the structure of PBIT provided the agent with additional novel cytotoxic and immunologic properties. Results from the in vitro and in vivo bioassays suggest that PBI-Se could be developed further for the prevention and treatment of colon cancer.

Influence of Se concentrations and species in hydroponic cultures on Se uptake, translocation and assimilation in non-accumulator ryegrass.

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Versini, Antoine; Di Tullo, Pamela; Aubry, Emmanuel; Bueno, Maïté; Thiry, Yves; Pannier, Florence; Castrec-Rouelle, Maryse

2016-11-01

The success of biofortification and phytoremediation practices, addressing Se deficiency and Se pollution issues, hinges crucially on the fate of selenium in the plant media in response to uptake, translocation and assimilation processes. We investigate the fate of selenium in root and shoot compartments after 3 and 6 weeks of experiment using a total of 128 plants grown in hydroponic solution supplied with 0.2, 2, 5, 20 and 100 mg L -1 of selenium in the form of selenite, selenate and a mixture of both species. Selenate-treated plants exhibited higher root-to-shoot Se translocation and total Se uptake than selenite-treated plants. Plants took advantage of the selenate mobility and presumably of the storage capacity of leaf vacuoles to circumvent selenium toxicity within the plant. Surprisingly, 28% of selenate was found in shoots of selenite-treated plants, questioning the ability of plants to oxidize selenite into selenate. Selenomethionine and methylated organo-selenium amounted to 30% and 8% respectively in shoots and 35% and 9% in roots of the identified Se, suggesting that selenium metabolization occurred concomitantly in root and shoot plant compartments and demonstrating that non-accumulator plants can synthesize notable quantities of precursor compound for volatilization. The present study demonstrated that non-accumulator plants can develop the same strategies as hyper-accumulator plants to limit selenium toxicity. When both selenate and selenite were supplied together, plants used selenate in a storage pathway and selenite in an assimilation pathway. Plants might thereby benefit from mixed supplies of selenite and selenate by saving enzymes and energy required for selenate reduction. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Plant selenium hyperaccumulation- Ecological effects and potential implications for selenium cycling and community structure.

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Reynolds, R Jason B; Pilon-Smits, Elizabeth A H

2018-04-25

Selenium (Se) hyperaccumulation occurs in ~50 plant taxa native to seleniferous soils in Western USA. Hyperaccumulator tissue Se levels, 1000-15,000 mg/kg dry weight, are typically 100 times higher than surrounding vegetation. Relative to other species, hyperaccumulators also transform Se more into organic forms. We review abiotic and biotic factors influencing soil Se distribution and bioavailability, soil being the source of the Se in hyperaccumulators. Next, we summarize the fate of Se in plants, particularly hyperaccumulators. We then extensively review the impact of plant Se accumulation on ecological interactions. Finally, we discuss the potential impact of Se hyperaccumulators on local community composition and Se cycling. Selenium (hyper)accumulation offers ecological advantages: protection from herbivores and pathogens and competitive advantage over other plants. The extreme Se levels in and around hyperaccumulators create a toxic environment for Se-sensitive ecological partners, while offering a niche for Se-resistant partners. Through these dual effects, hyperaccumulators may influence species composition in their local environment, as well as Se cycling. The implied effects of Se hyperaccumulation on community assembly and local Se cycling warrant further investigations into the contribution of hyperaccumulators and general terrestrial vegetation to global Se cycling and may serve as a case study for how trace elements influence ecological processes. Furthermore, understanding ecological implications of plant Se accumulation are vital for safe implementation of biofortification and phytoremediation, technologies increasingly implemented to battle Se deficiency and toxicity. Copyright © 2018. Published by Elsevier B.V.

Selenium (Se) improves drought tolerance in crop plants--a myth or fact?

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Ahmad, Rashid; Waraich, Ejaz Ahmad; Nawaz, Fahim; Ashraf, Muhammad Y; Khalid, Muhammad

2016-01-30

Climate change has emerged as one of the most complex challenges of the 21st century and has become an area of interest in the past few decades. Many countries of the world have become extremely vulnerable to the impacts of climate change. The scarcity of water is a serious concern for food security of these countries and climate change has aggravated the risks of extreme events like drought. Oxidative stress, caused by a variety of active oxygen species formed under drought stress, damages many cellular constituents, such as carbohydrates, lipids, nucleic acids and proteins, which ultimately reduces plant growth, respiration and photosynthesis. Se has become an element of interest to many biologists owing to its physiological and toxicological importance. It plays a beneficial role in plants by enhancing growth, reducing damage caused by oxidative stress, enhancing chlorophyll content under light stress, stimulating senesce to produce antioxidants and improving plant tolerance to drought stress by regulating water status. Researchers have adopted different strategies to evaluate the role of selenium in plants under drought stress. Some of the relevant work available regarding the role of Se in alleviating adverse effect of drought stress is discussed in this paper. © 2015 Society of Chemical Industry.

Chemical processing for production of no-carrier-added selenium-73 from germanium and arsenic targets and synthesis of L-2-amino-4-([73Se]methylseleno) butyric acid (L-[73Se]selenomethionine)

International Nuclear Information System (INIS)

Plenevaux, A.; Guillaume, M.; Brihaye, C.; Lemaire, C.; Cantineau, R.

1990-01-01

The Ge( 4 He,xn) and 75 As(p,3n) reactions were compared as the best potential routes for routine production of selenium-73 ( 73 Se) for medical applications. With 26 MeV α particles, available with compact cyclotrons, the first reaction required an enriched 70 Ge target of sodium metagermanate to give a production yield of 1 mCi/μAh (0.037 GBq/μAh) in a 105 mg/cm 2 target. With 55 MeV protons the As(p,3n) reaction on natural arsenic yielded 20 mCi/μAh (0.74 GBq/μAh) in a 685 mg/cm 2 target. A simple method was developed and optimized for both targets in order to isolate and purify the no-carrier-added selenium in the elemental form with a radiochemical yield greater than 75% in less than 90 min. An automated radiochemical processing unit has been designed for the routine production of 100-150 mCi(3.7-5.5 GBq) batches of carrier-free 73 Se ready for radiopharmaceutical labeling. 30 mCi (1.11 GBq) (EOS) of L-2-amino-4-([ 73 Se]methylseleno) butyric acid (L-[ 73 Se]selenomethionine) ready for injection with a specific activity of 5 Ci/mmol (185 GBq/mmol) (EOS) were obtained through a fast chemical synthesis. Radiation absorbed dose estimates for L-[ 73 Se ]selenomethionine have been determined. A value of 0.70 rem/mCi (0.19 mSv/MBq) administered was calculated for the risk from irradiation in man. The first human PET investigation with [ 73 Se]selenomethionine showed a very good delineation between liver and pancreas. (author)

Investigation of electrical noise in selenium-immersed thermistor bolometers

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Tarpley, J. L.; Sarmiento, P. D.

1980-01-01

The selenium immersed, thermistor bolometer, IR detector failed due to spurious and escalating electrical noise outburst as a function of time at elevated temperatures during routine ground based testing in a space simulated environment. Spectrographic analysis of failed bolometers revealed selenium pure zones in the insulating selenium arsenic (Se-As) glass film which surrounds the active sintered Mn, Ni, Co oxide flake. The selenium pure film was identified as a potentially serious failure mechanism. Significant changes were instituted in the manufacturing techniques along with more stringent process controls which eliminated the selenium pure film and successfully produced 22study bolometers.

Preparation and antioxidant properties of selenium nanoparticles-loaded chitosan microspheres

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Bai K

2017-06-01

Full Text Available Kaikai Bai,1,2 Bihong Hong,1,2 Jianlin He,1,2 Zhuan Hong,1,2 Ran Tan1,2 1Third Institute of Oceanography, 2Engineering Research Center of Marine Biological Resource, Comprehensive Utilization, State Oceanic Administration, Xiamen, People’s Republic of China Abstract: Selenium nanoparticles (SeNPs, as a special form of selenium (Se supplement, have attracted worldwide attention due to their favorable properties and unique bioactivities. Herein, an eco-friendly and economic way to prepare stable SeNPs is introduced. SeNPs were synthesized in aqueous chitosan (CTS and then embedded into CTS microspheres by spray-drying, forming selenium nanoparticles-loaded chitosan microspheres (SeNPs-M. The physicochemical properties including morphology, elemental state, size distribution and surface potential were investigated. Institute of Cancer Research mice were used as model animal to evaluate the bioactivities of SeNPs-M. Trigonal-phase SeNPs of ~35 nm were synthesized, and SeNPs-M physically embedding those SeNPs were successfully prepared. Amazingly, acute toxicity test indicated that SeNPs-M were much safer than selenite in terms of Se dose, with a LD50 of around 18-fold of that of selenite. In addition, SeNPs-M possessed powerful antioxidant activities, as evidenced by a dramatic increase of both Se retention and the levels of glutathione peroxidase, superoxide dismutase and catalase. The design of SeNPs-M can offer a new way for further development of SeNPs with a higher efficacy and better biosafety. Thus, SeNPs-M may be a potential candidate for further evaluation as an Se supplement with antioxidant properties and be used against Se deficiency in animals and human beings. Keywords: selenium, nano, microsphere, chitosan, antioxidant

Arsenic and selenium in microbial metabolism

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Stolz, John F.; Basu, Partha; Santini, Joanne M.; Oremland, Ronald S.

2006-01-01

Arsenic and selenium are readily metabolized by prokaryotes, participating in a full range of metabolic functions including assimilation, methylation, detoxification, and anaerobic respiration. Arsenic speciation and mobility is affected by microbes through oxidation/reduction reactions as part of resistance and respiratory processes. A robust arsenic cycle has been demonstrated in diverse environments. Respiratory arsenate reductases, arsenic methyltransferases, and new components in arsenic resistance have been recently described. The requirement for selenium stems primarily from its incorporation into selenocysteine and its function in selenoenzymes. Selenium oxyanions can serve as an electron acceptor in anaerobic respiration, forming distinct nanoparticles of elemental selenium that may be enriched in (76)Se. The biogenesis of selenoproteins has been elucidated, and selenium methyltransferases and a respiratory selenate reductase have also been described. This review highlights recent advances in ecology, biochemistry, and molecular biology and provides a prelude to the impact of genomics studies.

Determination of selenium in biological material by instrumental neutron activation analysis using 77m Se radioisotope

International Nuclear Information System (INIS)

Vasconcellos, Marina B.A.; Moreira, Edson G.; Catharino, Marilia G.M.; Tokura, Alexandra M.; Saiki, Mitiko

1999-01-01

Selenium is an essential element in human diet due to its relation to the protection against carcinogenic substances, heart disease, hypertension, sexual performance enhancement, and others. In this work Se concentration in samples of the biological certificate reference materials Human Hair BCR-CRM 397, Spiked Human Hair IAEA-085, Unspiked Human Hair IAEA-086; Dogfish Liver DOLT-1 and Dogfish Muscle DORM-1 were determined in order to improve the instrumental neutron activation analysis, INAA, method using 77m Se radioisotope. The application of this method allows the analysis of a large number of samples of samples with reduced time of experimental and cost. the best results were obtained with the reactor operating at 5 MW and time of irradiation between 10 and 20 s. In these experimental conditions the relative standard deviation and error were generally lower than 10%. (author)

Feasibility of measuring selenium in humans using in vivo neutron activation analysis.

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Tahir, S N A; Chettle, D R; Byun, S H; Prestwich, W V

2015-11-01

Selenium (Se) is an element that, in trace quantities, plays an important role in the normal function of a number of biological processes in humans. Many studies have demonstrated that selenium deficiency in the body may contribute to an increased risk for certain neoplastic, cardiovascular, osseous, and nervous system diseases including retardation of bone formation. However, at higher concentrations Se is cytotoxic. For these reasons it is desirable to have a means of monitoring selenium concentration in humans.This paper presents the outcome of a feasibility study carried out for measuring selenium in humans using in vivo neutron activation analysis (IVNAA). In this technique a small dose of neutrons is delivered to the organ of interest, the neutrons are readily captured by the target nuclei, and the γ-rays given off are detected outside of the body. For the present study, human hand (bone) tissue equivalent phantoms were prepared with varying amounts of Se. These were irradiated by a low energy fast neutron beam produced by the (7)Li(p,n)(7)Be reaction employing the high beam current Tandetron accelerator. The counting data saved using a 4π NaI(TI) detection system were analyzed. The selenium was detected via the neutron capture reaction, (76)Se(n,γ)(77 m)Se, whereas calcium was detected through the (48)Ca(n,γ)(49)Ca reaction for the purpose of normalization of the Se signals to the calcium signals. From the calibration lines drawn between Se/Ca concentrations and Se/Ca counts ratio, the minimum detection limits (MDLs) were computed for two sets of phantoms irradiated under different irradiation parameters.In this study the optimized MDL value was determined to be 81 ng g(-1) (Se/phantom mass) for an equivalent dose of 188 mSv to the phantom. This MDL was found at least 10 times lower than the reported data on Se concentration measured in bone tissues. It was concluded that the NAA technique would be a feasible means of performing in vivo measurements of

Effect of dietary supplementation with selenium-enriched yeast or sodium selenite on ruminal enzyme activities and blood chemistry in sheep

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Zita Faixová

2016-01-01

Full Text Available The experiment was conducted to evaluate the effect of feeding a diet supplemented with different forms of selenium on the rumen fluid, blood and serum enzyme activity and osmotic fragility of red blood cells in sheep. The experiment was carried out on 18 sheep of the Valashka breed at the age of 18 months, divided into 3 groups. The first group was given basal diet (BD with a Se content of 0.17 mg/kg of dry matter (DM. The second group received BD supplemented with 0.4 mg Se/kg of (DM in the form of sodium selenite. The third group received BD supplemented with 0.4 mg Se/kg of (DM in the form of Se-yeast extract. Duration of the trial was 12 weeks. Selenium concentration in blood and total rumen fluid were elevated in both supplemented groups with the highest values in Se-yeast-treated sheep. Blood glutathione peroxidase (GPx activity was significantly increased, regardless of the source of selenium. Osmotic resistance of red blood cells was not affected by selenium supplementation. The results indicate that feeding a diet supplemented with selenium from Se-yeast or selenite improved selenium status in blood and total rumen fluid. Selenium from sodium selenite was as effective as selenium from Se-yeast in the availability of selenium for the blood GPx activity. The effect of selenium supplementation on the ruminal enzyme activity depends on the selenium form; GGT and GDH were significantly higher in the Se-yeast supplement group, AST and ALP were significantly higher in the selenite supplement group.

Dietary advice on Inuit traditional food use needs to balance benefits and risks of mercury, selenium, and n3 fatty acids.

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Laird, Brian D; Goncharov, Alexey B; Egeland, Grace M; Chan, Hing Man

2013-06-01

Elevated concentrations of mercury (Hg) are commonly found in the traditional foods, including fish and marine mammals, of Inuit living in Canada's Arctic. As a result, Inuit often have higher dietary Hg intake and elevated Hg blood concentrations. However, these same traditional foods are excellent sources of essential nutrients. The goals of this study were 1) to identify the traditional food sources of Hg exposure for Inuit, 2) to estimate the percentage of Inuit who meet specific nutrient Dietary Reference Intakes and/or exceed the Toxicological Reference Values (TRVs), and 3) to evaluate options that maximize nutrient intake while minimizing contaminant exposure. A participatory cross-sectional survey was designed in consultation with Inuit in 3 Canadian Arctic jurisdictions (Nunatsiavut, Nunavut, and the Inuvialuit Settlement Region). Estimated intakes for EPA (20:5n3) and DHA (22:6n3) met suggested dietary targets, and estimated selenium (Se) intake fell within the Acceptable Range of Oral Intake. Estimated intakes of Hg (rs = 0.41, P Inuit.

Overview and prospects of selenium phytoremediation approaches

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Evidence is lacking on whether selenium (Se) is essential for vegetation growth, but plants can absorb, assimilate, and accumulate Se in leaves and roots. The capability of plants to take up substantial amount of Se is now being utilized to remove excess Se from contaminated soils. This process has ...

Biocompatibility selenium nanoparticles with an intrinsic oxidase-like activity

International Nuclear Information System (INIS)

Guo, Leilei; Huang, Kaixun; Liu, Hongmei

2016-01-01

Selenium nanoparticles (SeNPs) are considered to be the new selenium supplement forms with high biological activity and low toxicity; however, the molecular mechanism by which SeNPs exert the biological function is unclear. Here, we reported that biocompatibility SeNPs possessed intrinsic oxidase-like activity. Using Na 2 SeO 3 as a precursor and glutathione as a reductant, biocompatibility SeNPs were synthesized by the wet chemical reduction method in the presence of bovine serum albumin (BSA). The results of structure characterization revealed that synthesized SeNPs were amorphous red elementary selenium with spherical morphology, and ranged in size from 25 to 70 nm size with a narrow distribution (41.4 ± 6.7 nm). The oxidase-like activity of the as-synthesized SeNPs was tested with 3,3′,5,5′-tetramethylbenzidine (TMB) as a substrate. The results indicated that SeNPs could catalyze the oxidization of TMB by dissolved oxygen. These SeNPs showed an optimum catalytic activity at pH 4 and 30 °C, and the oxidase-like activity was higher as the concentration of SeNPs increased and the size of SeNPs decreased. The Michaelis constant (K m ) values and maximal reaction velocity (V max ) of the SeNPs for TMB oxidation were 0.0083 mol/L and 3.042 μmol/L min, respectively.

Biocompatibility selenium nanoparticles with an intrinsic oxidase-like activity

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Guo, Leilei; Huang, Kaixun; Liu, Hongmei

2016-03-01

Selenium nanoparticles (SeNPs) are considered to be the new selenium supplement forms with high biological activity and low toxicity; however, the molecular mechanism by which SeNPs exert the biological function is unclear. Here, we reported that biocompatibility SeNPs possessed intrinsic oxidase-like activity. Using Na2SeO3 as a precursor and glutathione as a reductant, biocompatibility SeNPs were synthesized by the wet chemical reduction method in the presence of bovine serum albumin (BSA). The results of structure characterization revealed that synthesized SeNPs were amorphous red elementary selenium with spherical morphology, and ranged in size from 25 to 70 nm size with a narrow distribution (41.4 ± 6.7 nm). The oxidase-like activity of the as-synthesized SeNPs was tested with 3,3',5,5'-tetramethylbenzidine (TMB) as a substrate. The results indicated that SeNPs could catalyze the oxidization of TMB by dissolved oxygen. These SeNPs showed an optimum catalytic activity at pH 4 and 30 °C, and the oxidase-like activity was higher as the concentration of SeNPs increased and the size of SeNPs decreased. The Michaelis constant ( K m) values and maximal reaction velocity ( V max) of the SeNPs for TMB oxidation were 0.0083 mol/L and 3.042 μmol/L min, respectively.

Determination of the solubility limiting solid of the selenium in the presence of iron under anoxic conditions

International Nuclear Information System (INIS)

Iida, Y.; Yamaguchi, T.; Tanaka, T.; Kitamura, A.; Nakayama, S.

2009-01-01

Dissolution experiments of selenium were performed from both under saturation and over saturation directions to determine the solubility limiting solid of selenium under the conditions which thermodynamically prefer the formation of ferroselite (FeSe 2 ). X-ray diffractometry (XRD) showed that FeSe 2 was formed in the over-saturation experiments. However, the ion activity products for the reaction of 0.5 FeSe 2 + H + + e - 0.5 Fe 2+ + HSe - , aFe 2+0.5 aHSe - a H+ -1 a e- -1 , obtained from both under saturation and over saturation directions were 3 to 4 orders of magnitude higher than the equilibrium constants calculated from existing thermodynamic data. The dependencies of the selenium concentration on pH, Eh and the iron concentration were better interpreted as a dissolution reaction of selenium solid (Se(s)) than the iron-selenium compounds. The equilibrium constant of: Se(s) + H + + 2e - = HSe - was determined to be logK 0 -7.46±0.11. This value agrees with the value of logK 0 = -7.62±0.06 calculated from existing thermodynamic data of crystalline selenium within errors. Because crystalline selenium was not identified in the solid phases by XRD, the solubility limiting solid would be amorphous or minor amount of crystalline selenium, even if the iron-selenium compound was formed. (authors)

Multispecies Biofilms Transform Selenium Oxyanions into Elemental Selenium Particles: Studies Using Combined Synchrotron X-ray Fluorescence Imaging and Scanning Transmission X-ray Microscopy

Energy Technology Data Exchange (ETDEWEB)

Yang, Soo In; George, Graham N.; Lawrence, John R.; Kaminskyj, Susan G. W.; Dynes, James J.; Lai, Barry; Pickering, Ingrid J.

2016-10-04

Selenium (Se) is an element of growing environmental concern, because low aqueous concentrations can lead to biomagnification through the aquatic food web. Biofilms, naturally occurring microbial consortia, play numerous important roles in the environment, especially in biogeochemical cycling of toxic elements in aquatic systems. The complexity of naturally forming multispecies biofilms presents challenges for characterization because conventional microscopic techniques require chemical and physical modifications of the sample. Here, multispecies biofilms biotransforming selenium oxyanions were characterized using X-ray fluorescence imaging (XFI) and scanning transmission X-ray microscopy (STXM). These complementary synchrotron techniques required minimal sample preparation and were applied correlatively to the same biofilm areas. Sub-micrometer XFI showed distributions of Se and endogenous metals, while Se K-edge X-ray absorption spectroscopy indicated the presence of elemental Se (Se0). Nanoscale carbon K-edge STXM revealed the distributions of microbial cells, extracellular polymeric substances (EPS), and lipids using the protein, saccharide, and lipid signatures, respectively, together with highly localized Se0 using the Se LIII edge. Transmission electron microscopy showed the electron-dense particle diameter to be 50–700 nm, suggesting Se0 nanoparticles. The intimate association of Se0 particles with protein and polysaccharide biofilm components has implications for the bioavailability of selenium in the environment.

Selenium and tellurium as carbon substitutes

International Nuclear Information System (INIS)

Knapp, F.F. Jr.

1980-01-01

This review has summarized structure-activity studies with 75 Se- and /sup 123m/Te-labeled radiopharmaceuticals in which the selenium or tellurium heteroatom has been inserted between carbon-carbon bonds. The agents that have been investigated in most detail include steroids for adrenal imaging and long-chain fatty acids, and a variety of other unique agents have also been studied. Because of the great versatility of the organic chemistry of selenium and tellurium, there is continuing interest in the preparation of radiopharmaceuticals labeled with 75 Se, 73 Se, and /sup 123m/Te. There are two important factors which will determine the extent of future interest in such agents. These include the necessity of a decrease in the cost of highly enriched 122 Te to make the reactor production of /sup 123m/Te cost effective. In addition, the potential preparation of large amounts of 73 Se should stimulate the development of 73 Se-labeled radiopharmaceuticals

SELENIUM SUBSTITUTION – EFFECT ON THYROID FUNCTION

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Milica Pešić

2015-03-01

Full Text Available The understanding of the essential role of selenium (Se in thyroid hormone synthesis, metabolism and action, as well as normal thyroid function, increased during the past decades. The thyroid gland is among the human tissues with the highest Se content per mas unit, similar to other endocrine organs and brain. Biological actions of Se are mediated, in most cases, through the expression of at least 30 selenoproteins coded by 25 selenoprotein genes in the human. Via the selenoproteins, selenium can influence the cell function through antioxidant activites, modifying redox status and thyroid hormone synthesis and metabolism. Selenoproteins iodothyronine deiodinases are present in most tissues and have a role to increase the production of bioactive tri-iodothyronine. Futhermore, Se has been shown to be important in the regulation of immune function. Se deficiency is accompained by the loss of immune competence. The links between Se deficiency, altered immune function and inflamation have prompted studies in humans to examine if Se suplementation can modify auto-antibodies production in patients with chronic autoimmune thyroiditis. Until now, several randomised prospective clinical trials have been performed in patients with established chronic autoimmune thyrioditis. The clinical endpoint of each study was the decrease in TPO antibodies concentration after 3-12 months of treatment. Ussualy, the dosage of daily Se supplementation was 200µg. Selenium suplemetation had no significant effect on the concentration of TSH or thyroid hormone concentrations. These studies indicate that Se treatment result in reduced inflammatory activity, but it does not cure chronc autoimmune process.

Identification QTLs Controlling Genes for Se Uptake in Lentil Seeds.

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Duygu Ates

Full Text Available Lentil (Lens culinaris Medik. is an excellent source of protein and carbohydrates and is also rich in essential trace elements for the human diet. Selenium (Se is an essential micronutrient for human health and nutrition, providing protection against several diseases and regulating important biological systems. Dietary intake of 55 μg of Se per day is recommended for adults, with inadequate Se intake causing significant health problems. The objective of this study was to identify and map quantitative trait loci (QTL of genes controlling Se accumulation in lentil seeds using a population of 96 recombinant inbred lines (RILs developed from the cross "PI 320937" × "Eston" grown in three different environments for two years (2012 and 2013. Se concentration in seed varied between 119 and 883 μg/kg. A linkage map consisting of 1,784 markers (4 SSRs, and 1,780 SNPs was developed. The map spanned a total length of 4,060.6 cM, consisting of 7 linkage groups (LGs with an average distance of 2.3 cM between adjacent markers. Four QTL regions and 36 putative QTL markers, with LOD scores ranging from 3.00 to 4.97, distributed across two linkage groups (LG2 and LG5 were associated with seed Se concentration, explaining 6.3-16.9% of the phenotypic variation.

Selenium Treatment Technologies

Science.gov (United States)

Selenium (Se) is a metalloid that is a dietary requirement in small quantities, but toxic at higher quantities. It also is known to bioaccumulate. In oxic environments, it exists as selenate (+6) and selenite (+4), both of which are soluble. Selenite will sorb more strongly to...

Effects of selenium biofortification on crop nutritional quality

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Mario eMalagoli

2015-04-01

Full Text Available Selenium (Se at very low doses has crucial functions in humans and animals. Since plants represent the main dietary source of this element, Se-containing crops may be used as a means to deliver Se to consumers (biofortification. Several strategies have been exploited to increase plant Se content. Selenium assimilation in plants affects both sulphur (S and nitrogen (N metabolic pathways, which is why recent research has also focused on the effect of Se fertilization on the production of S- and N- secondary metabolites with putative health benefits. In this review we discuss the function of Se in plant and human nutrition and the progress in the genetic engineering of Se metabolism to increase the levels and bioavailability of this element in food crops. Particular attention is paid to Se biofortification and the synthesis of compounds with beneficial effects on health.

Evaluation of the Content of Antimony, Arsenic, Bismuth, Selenium, Tellurium and Their Inorganic Forms in Commercially Baby Foods.

Science.gov (United States)

Ruiz-de-Cenzano, M; Rochina-Marco, A; Cervera, M L; de la Guardia, M

2017-12-01

Baby foods, from the Spanish market and prepared from meat, fish, vegetables, cereals, legumes, and fruits, were analyzed to obtain the concentration of antimony (Sb), arsenic (As), bismuth (Bi), and tellurium (Te) as toxic elements and selenium (Se) as essential element. An analytical procedure was employed based on atomic fluorescence spectroscopy which allowed to obtain accurate data at low levels of concentration. Values of 14 commercial samples, expressed in nanograms per gram fresh weight, ranged for Sb 0.66-6.9, As 4.5-242, Te 1.35-2.94, Bi 2.18-4.79, and Se 5.4-109. Additionally, speciation studies were performed based on data from a non-chromatographic screening method. It was concluded that tellurium and bismuth were mainly present as inorganic forms and selenium as organic form, and antimony and arsenic species depend on the ingredients of each baby food. Risk assessment considerations were made by comparing dietary intake of the aforementioned elements through the consumption of one baby food portion a day and recommended or tolerable guideline values.

Metabolism in rats of selenium from intrinsically and extrinsically labeled isolated soy protein

International Nuclear Information System (INIS)

Mason, A.C.; Weaver, C.M.

1986-01-01

Absorption, retention and tissue accumulation by rats of 75 Se from intrinsically labeled isolated soy protein were compared with utilization of 75 Se from the extrinsic sources of [ 75 Se]selenite, [ 75 Se]selenate or [ 75 Se]selenomethionine. Extrinsic sources of selenium were given by gavage or mixed with isolated soy protein. There were no differences in absorption and retention of 75 Se from intrinsically labeled soy diet compared to the three extrinsically labeled soy diets. Of the three extrinsic sources tested, 75 Se from selenate was better absorbed than from selenite or selenomethionine when incorporated into a soy diet. Absorption of 75 Se was significantly lower when given to animals in gavage solution than when mixed with soy diets. After a 14-d test period, retention of 75 Se was the same for all four soy diet groups. In gavaged groups, 75 Se from selenomethionine was retained to a greater extent than 75 Se from selenite. The liver, testes and kidney accumulated more 75 Se from the test meal than did the blood and lungs. In the testes more 75 Se from selenite and selenate was accumulated than from selenomethionine-labeled diets. Selenium absorption from the soy isolate source was very high (86-96%), indicating that, although soy does not normally contain high levels of selenium, the selenium present is well absorbed from this plant source

Full four-component relativistic calculations of the one-bond 77Se-13C spin-spin coupling constants in the series of selenium heterocycles and their parent open-chain selenides.

Science.gov (United States)

Rusakov, Yury Yu; Rusakova, Irina L; Krivdin, Leonid B

2014-05-01

Four-component relativistic calculations of (77)Se-(13)C spin-spin coupling constants have been performed in the series of selenium heterocycles and their parent open-chain selenides. It has been found that relativistic effects play an essential role in the selenium-carbon coupling mechanism and could result in a contribution of as much as 15-25% of the total values of the one-bond selenium-carbon spin-spin coupling constants. In the overall contribution of the relativistic effects to the total values of (1)J(Se,C), the scalar relativistic corrections (negative in sign) by far dominate over the spin-orbit ones (positive in sign), the latter being of less than 5%, as compared to the former (ca 20%). A combination of nonrelativistic second-order polarization propagator approach (CC2) with the four-component relativistic density functional theory scheme is recommended as a versatile tool for the calculation of (1)J(Se,C). Solvent effects in the values of (1)J(Se,C) calculated within the polarizable continuum model for the solvents with different dielectric constants (ε 2.2-78.4) are next to negligible decreasing negative (1)J(Se,C) in absolute value by only about 1 Hz. The use of the locally dense basis set approach applied herewith for the calculation of (77)Se-(13)C spin-spin coupling constants is fully justified resulting in a dramatic decrease in computational cost with only 0.1-0.2-Hz loss of accuracy. Copyright © 2014 John Wiley & Sons, Ltd.

Selenium Utilization Strategy by Microalgae

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Hiroya Araie

2009-11-01

Full Text Available The diversity of selenoproteins raises the question of why so many life forms require selenium. Selenoproteins are found in bacteria, archaea, and many eukaryotes. In photosynthetic microorganisms, the essential requirement for selenium has been reported in 33 species belonging to six phyla, although its biochemical significance is still unclear. According to genome databases, 20 species are defined as selenoprotein-producing organisms, including five photosynthetic organisms. In a marine coccolithophorid, Emiliania huxleyi (Haptophyta, we recently found unique characteristics of selenium utilization and novel selenoproteins using 75Se-tracer experiments. In E. huxleyi, selenite, not selenate, is the main substrate used and its uptake is driven by an ATP-dependent highaffinity, active transport system. Selenite is immediately metabolized to low-molecular mass compounds and partly converted to at least six selenoproteins, named EhSEP1–6. The most (EhSEP2 and second-most abundant selenoproteins (EhSEP1 are disulfide isomerase (PDI homologous protein and thioredoxin reductase (TR 1, respectively. Involvement of selenium in PDI is unique in this organism, while TR1 is also found in other organisms. In this review, we summarize physiological, biochemical, and molecular aspects of selenium utilization by microalgae and discuss their strategy of selenium utilization.

Assessment of serum selenium levels in 2-month-old sucking calves using total reflection technique

International Nuclear Information System (INIS)

Bernardini, D.; Testoni, S.; Buoso, M.C.; Ceccato, D.; Moschini, G.; Valdes, M.; Torboli, A.

2000-01-01

The assessment of selenium status of livestock is an important aspect of production medicine as evidence for the influence of low Se levels on disease resistance in ruminants is reviewed with emphasis on susceptibility to various pathologies (such as infections, exudative diathesis, pneumonia, pancreatic degeneration). Additional evidence suggests that Se deficiency may cause muscular dystrophy in calves, while, severe deficiency has been associated with cardiomyopathy and even death. Serum Se content is a good indicator of the short term Se status and reflects the recent dietary intake of the element. Since serum Se content is a good indicator of the short term status of the element and reflects the its recent dietary intake, the present work is aimed to determine Se concentration in serum from a group of 2 months old sucking calves suspected to be severely deficient. We used the TX 2000 X-ray spectrometer manufactured by Ital Structures. The energy resolution (FWHM) of the Si(Li) detector was 137 eV for Mn Kα. Among nuclear techniques the TXRF method is the best suitable for trace element analysis in liquid or dissolved samples and can deal much easier with elemental investigation. Physical basis of used analytical method, experimental set up and the sample preparation procedure are described. The concentration data obtained are presented and discussed. (author)

Genome Sequence of Selenium-Solubilizing Bacterium Caulobacter vibrioides T5M6

DEFF Research Database (Denmark)

Wang, Yihua; Qin, Yanan; Kot, Witold

2016-01-01

Caulobacter vibrioides T5M6 is a Gram-negative strain that strongly solubilizes selenium (Se) mineral into Se(IV) and was isolated from a selenium mining area in Enshi, southwest China. This strain produces the phytohormone IAA and promotes plant growth. Here we present the genome of this strain...

Extracellular Polymeric Substances Govern the Surface Charge of Biogenic Elemental Selenium Nanoparticles

KAUST Repository

Jain, Rohan

2015-02-03

© 2014 American Chemical Society. The origin of the organic layer covering colloidal biogenic elemental selenium nanoparticles (BioSeNPs) is not known, particularly in the case when they are synthesized by complex microbial communities. This study investigated the presence of extracellular polymeric substances (EPS) on BioSeNPs. The role of EPS in capping the extracellularly available BioSeNPs was also examined. Fourier transform infrared (FT-IR) spectroscopy and colorimetric measurements confirmed the presence of functional groups characteristic of proteins and carbohydrates on the BioSeNPs, suggesting the presence of EPS. Chemical synthesis of elemental selenium nanoparticles in the presence of EPS, extracted from selenite fed anaerobic granular sludge, yielded stable colloidal spherical selenium nanoparticles. Furthermore, extracted EPS, BioSeNPs, and chemically synthesized EPS-capped selenium nanoparticles had similar surface properties, as shown by ζ-potential versus pH profiles and isoelectric point measurements. This study shows that the EPS of anaerobic granular sludge form the organic layer present on the BioSeNPs synthesized by these granules. The EPS also govern the surface charge of these BioSeNPs, thereby contributing to their colloidal properties, hence affecting their fate in the environment and the efficiency of bioremediation technologies.

Uptake and speciation of selenium in garlic cultivated in soil amended with symbiotic fungi (mycorrhiza) and selenate

Energy Technology Data Exchange (ETDEWEB)

Larsen, Erik H.; Hansen, Marianne; Rasmussen, Peter Have; Sloth, Jens J. [Danish Institute for Food and Veterinary Research, Department of Food Chemistry, Soeborg (Denmark); Lobinski, Ryszard; Ruzik, Rafal; Mazurowska, Lena [CNRS UMR 5034, Pau (France); Warsaw University of Technology, Department of Analytical Chemistry, Warsaw (Poland); Burger-Meyer, Karin; Scholten, Olga [Wageningen University and Research Centre, Plant Research International (PRI), P.O. Box 16, Wageningen (Netherlands); Kik, Chris [Wageningen University and Research Centre, Plant Research International (PRI), P.O. Box 16, Wageningen (Netherlands); Wageningen University and Research Centre, Centre for Genetic Resources, The Netherlands (CGN), P.O. Box 16, Wageningen (Netherlands)

2006-07-15

The scope of the work was to investigate the influence of selenate fertilisation and the addition of symbiotic fungi (mycorrhiza) to soil on selenium and selenium species concentrations in garlic. The selenium species were extracted from garlic cultivated in experimental plots by proteolytic enzymes, which ensured liberation of selenium species contained in peptides or proteins. Separate extractions using an aqueous solution of enzyme-deactivating hydroxylamine hydrochloride counteracted the possible degradation of labile selenium species by enzymes (such as alliinase) that occur naturally in garlic. The selenium content in garlic, which was analysed by ICP-MS, showed that addition of mycorrhiza to the natural soil increased the selenium uptake by garlic tenfold to 15 {mu}g g{sup -1} (dry mass). Fertilisation with selenate and addition of mycorrhiza strongly increased the selenium content in garlic to around one part per thousand. The parallel analysis of the sample extracts by cation exchange and reversed-phase HPLC with ICP-MS detection showed that {gamma}-glutamyl-Se-methyl-selenocysteine amounted to 2/3, whereas methylselenocysteine, selenomethionine and selenate each amounted to a few percent of the total chromatographed selenium in all garlic samples. Se-allyl-selenocysteine and Se-propyl-selenocysteine, which are selenium analogues of biologically active sulfur-containing amino acids known to occur in garlic, were searched for but not detected in any of the extracts. The amendment of soil by mycorrhiza and/or by selenate increased the content of selenium but not the distribution of detected selenium species in garlic. Finally, the use of two-dimensional HPLC (size exclusion followed by reversed-phase) allowed the structural characterisation of {gamma}-glutamyl-Se-methyl-selenocysteine and {gamma}-glutamyl-Se-methyl-selenomethionine in isolated chromatographic fractions by quadrupole time-of-flight mass spectrometry. (orig.)

Effect of selenium on its content in milk and performance of dairy cows in ecological farming

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Pavel Horký

2015-08-01

Full Text Available Currently, the ecological farming is increasingly spread in the European Union. The aim of this relatively young farming method is a friendly approach to agricultural production with an emphasis to deliver healthy raw materials and food to final consumer. Selenium is included in an essential trace micronutrients which are necessary for the proper process of physiological reactions. It is a part of glutathione peroxidase, which is a powerful antioxidant. At present,  selenium-deficiency can occur in feed and food in central Europe. Selenium deficiency is one cause of the higher occurrence of cardiovascular diseases. The aim of the experiment was to study whether the addition of selenium to the diet of dairy cows in ecological farming can increase its concentration in milk and affect quantitative (milk yield and quality (content of protein, fat, lactose, somatic cells and urea milk indicators. The experiment included twenty cows of Holstein breed. The first experimental group of cows (n = 10 was fed with selenium in an amount of 0.3 mg.kg-1 (as selenomethionine in the feed dose. The control group (n = 10 was not fed with the increased selenium in the feed dose. The basic feed dose contained 0.17 mg of Se/kg in the diet. For dairy cows, daily intake was of 20.5 kg of dry matter feed. The duration of the experiment was set at 45 days. The selenium concentration in milk was measured from 0.13 to 0.15 µg.mL-1 in the experimental group of cows during the evaluation. The control group of cows without the addition of selenium to the diet showed a selenium concentration below the detection limit. During the experiment, milk yield, lactose, fat and protein were not affected. A significant decrease (p <0.05 of somatic cells by 58% occurred in milk in the experimental group. The amount of urea was significantly lower in both groups in the experimental (by 52%; p <0.05 and control (50%; p <0.05. These results show that the addition of selenium may increase

Optimization of wet digestion procedure of blood and tissue for selenium determination by means of 75Se tracer

International Nuclear Information System (INIS)

Holynska, B.; Lipinska-Kalita, K.

1977-01-01

Selenium-75 tracer has been used for optimization of analytical procedure of selenium determination in blood and tissue. Wet digestion procedure and reduction of selenium to its elemental form with tellurium as coprecipitant have been tested. It is seen that the use of a mixture of perchloric and sulphuric acid with sodium molybdenate for the wet digestion of organic matter followed by the reduction of selenium to its elementary form by a mixture of stannous chloride and hydroxylamine hydrochloride results in very good recovery of selenium. Recovery of selenium obtained with the use of optimized analytical procedure amounts to 95% and precision is equal to 4.2%. (T.I.)

Synthesis of /sup 75/Se-2-phenyl-1,2-benzisoselenazol-3(2H)-one (PZ 51; Ebselen). A novel biologically active organo-selenium compound

Energy Technology Data Exchange (ETDEWEB)

Cantineau, R.; Tihange, G.; Plenevaux, A.; Christiaens, L.; Guillaume, M.; Welter, A.; Dereu, N.

1986-01-01

The preparation of /sup 75/Se-ebselen (/sup 75/Se-PZ 51) in a high radiochemical yield (approx. 40%) and with a specific activity of 240 mCi/mM (8.9 GBq/mM) is described. It entails a very simple, fast and one-pot procedure starting from elemental /sup 75/Se-selenium. /sup 75/Se-diselenosalicylic acid is initially prepared as the key intermediate which is transformed into a corresponding dichloride before reacting with aniline to yield the desired /sup 75/Se-ebselen. Identity and purity of the labelled compound were controlled by comparison in TLC, HPLC and MS with an authentic sample.

Biocompatibility selenium nanoparticles with an intrinsic oxidase-like activity

Energy Technology Data Exchange (ETDEWEB)

Guo, Leilei; Huang, Kaixun; Liu, Hongmei, E-mail: hmliu2004@126.com [Huazhong University of Science and Technology, School of Chemistry and Chemical Engineering (China)

2016-03-15

Selenium nanoparticles (SeNPs) are considered to be the new selenium supplement forms with high biological activity and low toxicity; however, the molecular mechanism by which SeNPs exert the biological function is unclear. Here, we reported that biocompatibility SeNPs possessed intrinsic oxidase-like activity. Using Na{sub 2}SeO{sub 3} as a precursor and glutathione as a reductant, biocompatibility SeNPs were synthesized by the wet chemical reduction method in the presence of bovine serum albumin (BSA). The results of structure characterization revealed that synthesized SeNPs were amorphous red elementary selenium with spherical morphology, and ranged in size from 25 to 70 nm size with a narrow distribution (41.4 ± 6.7 nm). The oxidase-like activity of the as-synthesized SeNPs was tested with 3,3′,5,5′-tetramethylbenzidine (TMB) as a substrate. The results indicated that SeNPs could catalyze the oxidization of TMB by dissolved oxygen. These SeNPs showed an optimum catalytic activity at pH 4 and 30 °C, and the oxidase-like activity was higher as the concentration of SeNPs increased and the size of SeNPs decreased. The Michaelis constant (K{sub m}) values and maximal reaction velocity (V{sub max}) of the SeNPs for TMB oxidation were 0.0083 mol/L and 3.042 μmol/L min, respectively.

Biogenesis of Selenium Nanoparticles Using Green Chemistry.

Science.gov (United States)

Shoeibi, Sara; Mozdziak, Paul; Golkar-Narenji, Afsaneh

2017-11-09

Selenium binds some enzymes such as glutathione peroxidase and thioredoxin reductase, which may be activated in biological infections and oxidative stress. Chemical and physical methods for synthesizing nanoparticles, apart from being expensive, have their own particular risks. However, nanoparticle synthesis through green chemistry is a safe procedure that different biological sources such as bacteria, fungi, yeasts, algae and plants can be the catalyst bed for processing. Synthesis of selenium nanoparticles (SeNPs) by macro/microorganisms causes variation in morphology and shape of the particles is due to diversity of reduction enzymes in organisms. Reducing enzymes of microorganisms by changing the status of redox convert metal ions (Se 2- ) to SeNPs without charge (Se 0 ). Biological activity of SeNPs includes their protective role against DNA oxidation. Because of the biological and industrial properties, SeNPs have wide applications in the fields of medicine, microelectronic, agriculture and animal husbandry. SeNPs can show strong antimicrobial effects on the growth and proliferation of microorganisms in a dose-dependent manner. The objective of this review is to consider SeNPs applications to various organisms.

Polymer supported synthesis of unsymmetrical n.c.a. selenium-73/75 ethers for the labelling of amino acids

International Nuclear Information System (INIS)

Schmaljohann, J.

1995-09-01

The synthesis of n.c.a. selenium-73/75 labelled methionine and of a selenoalkylation agent have been performed according to a reaction including a primary, polymer supported alkylation step. The selenium-75 was produced through the 75 As(p, n)-process and separated as [ 75 Se]selenium dioxide by thermochromatography. The [ 75 Se]SeO 2 -sublimate was dissolved in hydrochloric acid and reduced with sulfur dioxide to obtain elemental n.c.a. selenium-75, which was extracted into benzene. Reaction of the elemental n.c.a. selenium-75 with polymeric bound triphenylphosphine led to the formation of the corresponding [ 75 Se]triphenylphosphinselenide in a nearly quantitative yield. The asymmetrical [ 75 Se]selenoethers were synthesized in homogeneous phase through the reaction of the [ 75 Se]MeSe - with propylhalides in radiochemical yields up of to 55%. A selenium-75 labelled prosthetic group was synthesized in radiochemical yields of 48% by the reaction of 1-chloro-3-iodopropane with the [ 75 ]selenation reagent [ 75 Se]MeSe - . For labelling amino functions via [ 75 Se]selenoalkylation the [ 75 Se]selenated propyl chloride has to be transfered into the iodide with sodium iodide, which was performed in radiochemical yields of 90%. After the reaction of [ 75 Se]-1-iodo-3-(methylseleno)propane with butylamine or with N α -, O-protected lysine in DMF at 80 C the [ 75 Se]methylselenopropylated products were obtained in radiochemical yields of 95% and 90%, respectively. (orig./SR)

Facile Synthesis and Optical Properties of Small Selenium Nanocrystals and Nanorods

Science.gov (United States)

Jiang, Fengrui; Cai, Weiquan; Tan, Guolong

2017-06-01

Selenium is an important element for human's health, small size is very helpful for Se nanoparticles to be absorbed by human's body. Here, we present a facile approach to fabrication of small selenium nanoparticles (Nano-Se) as well as nanorods by dissolving sodium selenite (Na2SeO3) in glycerin and using glucose as the reduction agent. The as-prepared selenium nanoparticles have been characterized by X-ray diffraction (XRD), UV-Vis absorption spectroscopy and high resolution transmission electron microscope (HRTEM). The morphology of small Se nanoparticles and nanorods have been demonstrated in the TEM images. A small amount of 3-mercaptoproprionic acid (MPA) and glycerin play a key role on controlling the particle size and stabilize the dispersion of Nano-Se in the glycerin solution. In this way, we obtained very small and uniform Se nanoparticles; whose size ranges from 2 to 6 nm. This dimension is much smaller than the best value (>20 nm) ever reported in the literatures. Strong quantum confinement effect has been observed upon the size-dependent optical spectrum of these Se nanoparticles.

EPR of SeO2- and SeO3- radicals in alkaline borate glasses with 77Se isotope

International Nuclear Information System (INIS)

Galimov, D.G.; Tarzimanov, K.D.

1977-01-01

Alkaline borate glasses with 77 Se were investigated in order to establish the nature of selenium compounds and radicals in glasses. The relationship between alkali ions and the oxygen radical of selenium was determined by decoding the hyperfine structure of the alkaline borate glass EPR spectra obtained before and after γ-irradiation. The irradiated and non-irradiated glasses were characterized by hyperfine splitting of the EPR lines from the α- and β centres. Moreover, the irradiated samples were noted to have a line doublet (signal phi). With intenser reduction conditions of glass fusion, the intensities of α, β, and phi signals were noted to decline. This confirmes the suggestion that these centres were caused by oxygen compouds. The authors concluded that α and β signals were due to the paramagnetic centres of SeO 2 - and [SeO 2 - ]R + , and phi signal to the SeO 3 - radicals

Biofortification and phytoremediation of selenium in China

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Zhilin eWu

2015-03-01

Full Text Available Selenium (Se is an essential trace element for humans and animals but at high concentrations, Se becomes toxic to organisms due to Se replacing sulfur in proteins. Selenium biofortification is an agricultural process that increases the accumulation of Se in crops, through plant breeding, genetic engineering, or use of Se fertilizers. While Se phytoremediation is a green biotechnology to clean up Se-contaminated environments, primarily through phytoextraction and phytovolatilization. By integrating Se phytoremediation and biofortification technologies, Se-enriched plant materials harvested from Se phytoremediation can be used as Se-enriched green manures or other supplementary sources of Se for producing Se-biofortified agricultural products. Earlier studies primarily aimed at enhancing efficacy of phytoremediation and biofortification of Se based on natural variation in progenitor or identification of unique plant species. In this review, we discuss promising approaches to improve biofortification and phytoremediation of Se using knowledge acquired from model crops. We also explored the feasibility of applying biotechnologies such as inoculation of microbial strains for improving the efficiency of biofortification and phytoremediation of Se. The key research and practical challenges that remain in improving biofortification and phytoremediation of Se have been highlighted, and the future development and uses of Se-biofortified agricultural products in China has also been discussed.

Elucidating the selenium and arsenic metabolic pathways following exposure to the non-hyperaccumulating Chlorophytum comosum, spider plant

Science.gov (United States)

Afton, Scott E.; Catron, Brittany; Caruso, Joseph A.

2009-01-01

Although many studies have investigated the metabolism of selenium and arsenic in hyperaccumulating plants for phytoremediation purposes, few have explored non-hyperaccumulating plants as a model for general contaminant exposure to plants. In addition, the result of simultaneous supplementation with selenium and arsenic has not been investigated in plants. In this study, Chlorophytum comosum, commonly known as the spider plant, was used to investigate the metabolism of selenium and arsenic after single and simultaneous supplementation. Size exclusion and ion-pairing reversed phase liquid chromatography were coupled to an inductively coupled plasma mass spectrometer to obtain putative metabolic information of the selenium and arsenic species in C. comosum after a mild aqueous extraction. The chromatographic results depict that selenium and arsenic species were sequestered in the roots and generally conserved upon translocation to the leaves. The data suggest that selenium was directly absorbed by C. comosum roots when supplemented with SeVI, but a combination of passive and direct absorption occurred when supplemented with SeIV due to the partial oxidation of SeIV to SeVI in the rhizosphere. Higher molecular weight selenium species were more prevalent in the roots of plants supplemented with SeIV, but in the leaves of plants supplemented with SeVI due to an increased translocation rate. When supplemented as AsIII, arsenic is proposed to be passively absorbed as AsIII and partially oxidized to AsV in the plant root. Although total elemental analysis demonstrates a selenium and arsenic antagonism, a compound containing selenium and arsenic was not present in the general aqueous extract of the plant. PMID:19273464

Nanocrystalline hydroxyapatite doped with selenium oxyanions: A new material for potential biomedical applications

International Nuclear Information System (INIS)

Kolmas, Joanna; Oledzka, Ewa; Sobczak, Marcin; Nałęcz-Jawecki, Grzegorz

2014-01-01

Selenium-substituted hydroxyapatites containing selenate SeO 4 2− or selenite SeO 3 2− ions were synthesized using a wet precipitation method. The selenium content was determined by atomic absorbance spectrometry. The raw, unsintered powders were also characterized using powder X-ray diffraction, middle-range FT-IR spectroscopy and transmission electron microscopy with energy-dispersive X-ray spectroscopic microanalysis. The synthesized apatites were found to be pure and nanocrystalline with a crystal size similar to that in bone mineral. The incorporation of selenium oxyanions into the crystal lattice was confirmed. The toxicity of hydroxyapatites containing selenite or selenate ions was evaluated with a protozoan assay and bacterial luminescence test. - Highlights: • We synthesized and analyzed hydroxyapatites doped with selenium oxyanions. • We used various analytical methods, i.e. XRD, TEM, AAS and FT-IR. • We confirmed incorporation of SeO 3 2− and SeO 4 2− into the crystal lattice. • The toxicity of the materials was studied

Optimization of wet digestion procedure of blood and tissue for selenium determination by means of 75Se tracer

International Nuclear Information System (INIS)

Holynska, B.; Lipinska, K.

1977-01-01

Selenium-75 tracer has been used for optimization of analytical procedure of selenium determination in blood and tissue. Wet digestion procedure and reduction of selenium to its elemental form with tellurium as coprecipitant have been tested. Recovery of selenium obtained with the use of optimized analytical procedure amounts up 95% and precision is equal to 4.2%. (author)

Quantitative selenium speciation in human urine by using liquid chromatography–electrospray tandem mass spectrometry

International Nuclear Information System (INIS)

Lu Ying; Rumpler, Alice; Francesconi, Kevin A.; Pergantis, Spiros A.

2012-01-01

Highlights: ► Development of a selected reaction monitoring mass spectrometric method for the identification of Se species in human urine. ► A selenosugar was detected as the major human urinary metabolite of selenium in the samples analysed. ► The trimethylselenonium ion was detected in the urine of one volunteer before and after receiving a selenium supplement. ► Strict quality control measures were applied to validate identification. ► Quantitation was conducted using an isotopically labelled internal standard and the standard additions methodology. - Abstract: A liquid chromatography–electrospray-tandem mass spectrometry (ES-MS/MS) method was developed for the speciation analysis of four organic selenium species of relevance to human urinary metabolism, namely trimethylselenomium ion (TMSe + ), selenomethionine (SeMet) and the two selenosugars, methyl 2-acetamido-2-deoxy-1-seleno-β-D-galactos/-glucos-amine (SeGalNAc and SeGluNAc, respectively). Their chromatographic separation was achieved by using a cation exchange pre-column coupled in-series with a reversed-phase high-performance liquid chromatography column, along with an isocratic mobile phase. Online detection was performed using ES-MS/MS in selective reaction monitoring mode. SeGalNAc was detected as the major human urinary metabolite of selenium in the samples analysed, whereas TMSe + was detected in the urine of one volunteer before and after receiving a selenium supplement. SeMet was not detected as a urine excretory metabolite in this study. Spiking experiments performed with the urine samples revealed significant signal suppression caused by coeluting matrix constituents. To overcome such interferences, isotopically labelled 13 CD 3 82 SeGalNAc was used as an internal standard, whereas in the absence of an isotopically labelled internal standard for TMSe + , the standard addition method was applied. Quality control for the accurate quantitation of TMSe + and SeGalNAc was carried out by

Reduction of selenite by Azospirillum brasilense with the formation of selenium nanoparticles.

Science.gov (United States)

Tugarova, Anna V; Vetchinkina, Elena P; Loshchinina, Ekaterina A; Burov, Andrei M; Nikitina, Valentina E; Kamnev, Alexander A

2014-10-01

The ability to reduce selenite (SeO(3)(2-)) ions with the formation of selenium nanoparticles was demonstrated in Azospirillum brasilense for the first time. The influence of selenite ions on the growth of A. brasilense Sp7 and Sp245, two widely studied wild-type strains, was investigated. Growth of cultures on both liquid and solid (2 % agar) media in the presence of SeO(3)(2-) was found to be accompanied by the appearance of the typical red colouration. By means of transmission electron microscopy (TEM), electron energy loss spectroscopy (EELS) and X-ray fluorescence analysis (XFA), intracellular accumulation of elementary selenium in the form of nanoparticles (50 to 400 nm in diameter) was demonstrated for both strains. The proposed mechanism of selenite-to-selenium (0) reduction could involve SeO(3)(2-) in the denitrification process, which has been well studied in azospirilla, rather than a selenite detoxification strategy. The results obtained point to the possibility of using Azospirillum strains as endophytic or rhizospheric bacteria to assist phytoremediation of, and cereal cultivation on, selenium-contaminated soils. The ability of A. brasilense to synthesise selenium nanoparticles may be of interest to nanobiotechnology for "green synthesis" of bioavailable amorphous red selenium nanostructures.

Analyses of Selenotranscriptomes and Selenium Concentrations in Response to Dietary Selenium Deficiency and Age Reveal Common and Distinct Patterns by Tissue and Sex in Telomere-Dysfunctional Mice.

Science.gov (United States)

Cao, Lei; Zhang, Li; Zeng, Huawei; Wu, Ryan Ty; Wu, Tung-Lung; Cheng, Wen-Hsing

2017-10-01

Background: The hierarchies of tissue selenium distribution and selenotranscriptomes are thought to critically affect healthspan and longevity. Objective: We determined selenium status and selenotranscriptomes in response to long-term dietary selenium deficiency and age in tissues of male and female mice. Methods: Weanling telomerase RNA component knockout C57BL/6 mice were fed a selenium-deficient (0.03 mg Se/kg) Torula yeast-based AIN-93G diet or a diet supplemented with sodium selenate (0.15 mg Se/kg) until age 18 or 24 mo. Plasma, hearts, kidneys, livers, and testes were collected to assay for selenotranscriptomes, selected selenoproteins, and tissue selenium concentrations. Data were analyzed with the use of 2-factor ANOVA (diet × age) in both sexes. Results: Dietary selenium deficiency decreased ( P ≤ 0.05) selenium concentrations (65-72%) and glutathione peroxidase (GPX) 3 (82-94%) and selenoprotein P (SELENOP) (17-41%) levels in the plasma of both sexes of mice and mRNA levels (9-68%) of 4, 4, and 12 selenoproteins in the heart, kidney, and liver of males, respectively, and 5, 16, and 14 selenoproteins, respectively, in females. Age increased selenium concentrations and SELENOP levels (27% and 30%, respectively; P ≤ 0.05) in the plasma of males only but decreased (12-46%; P selenium deficiency and age in ≥1 tissue or sex, or both. Dietary selenium deficiency upregulated (40-160%; P ≤ 0.05) iodothyronine deiodinase 2 ( Dio2 ) and selenoprotein N ( Selenon ) in the kidneys of males. Age upregulated (11-44%; P selenium status and selenotranscriptomes because of dietary selenium deficiency and age. © 2017 American Society for Nutrition.

Iodine and selenium migration through argillaceous rocks

International Nuclear Information System (INIS)

Frasca, Benjamin

2011-01-01

Deep argillaceous formations are considered as potential host rock for high-level radioactive waste repository. Based on safety assessment calculations, active selenium ( 79 Se) and iodine ( 129 I) from high level radioactive waste might be ones of the major dose contributors due to their longevity and their anionic character. However, because of their high sensitivity to redox condition, a special attention to the oxidation state of these elements is required. A comparative study on the diffusion properties of selenium and iodine through argillaceous rocks was realized with the aim to determine the effects of both the redox conditions and the mineralogy on the migration of these two elements. For these purposes, we have studied two argillaceous rocks: Toarcian argillite from Tournemire (France) and Opalinus clay (OPA) from the Mont-Terri (Switzerland). The study of the iodide migration allowed to confirm the control on the iodide retention of both oxidized pyrite and natural organic matter. A kinetic control of the iodide sorption is also suspected. We focus the selenium study on the more oxidized species, Se(IV) and Se(VI). The Se(IV) migration is strongly dependant from oxido-reduction processes. Indeed, the Se(IV) diffusion experiments through Tournemire argillite and OPA indicated a significant reduction associated to Fe(II). The Se(VI) study evidenced a behavior dependant from the initial concentration: at the highest concentration, no significant retention was observed while the retention is significant at the lowest concentration. Furthermore, spectroscopic analyses tend to show a low Se(VI) reduction at the Fe contact. However, biotic origin cannot be excluded. (author)

Characterisation of selenium compounds in rye seedling biomass using {sup 75}Se-labelling/SDS-PAGE separation/{gamma}-scintillation counting, and HPLC-ICP-MS analysis of a range of enzymatic digests

Energy Technology Data Exchange (ETDEWEB)

Bryszewska, Malgorzata A. [Technical University of Lodz (Poland). Institute of General Food Chemistry; Ambroziak, Wojciech [Technical University of Lodz (Poland). Institute of Fermentation Technology and Microbiology; Rudzinski, Juliusz [Technical University of Lodz (Poland). Institute of Applied Radiation Chemistry; Lewis, D. John [Central Science Laboratory, York (United Kingdom)

2005-07-01

In the present study, selenium-enriched plant biomass was investigated to evaluate the ability of rye seedlings to take up, and assimilate, inorganic selenium. Two different analytical approaches were used. Electrophoretic separation (SDS-PAGE) of proteins extracted from {sup 75}Se-labelled biomass was used to investigate the biotransformation of selenite into organic forms of the element. Ion-pair chromatography coupled with ICP-MS detection was chosen for the analysis of selenium species, enzymatically extracted from the plant biomass. The results of three enzymatic hydrolysis procedures and three sequential enzymatic extractions procedures are compared. The most effective single extraction was proteolysis (using protease type XIV), giving an overall extraction efficiency of 48%. However, for combinations of enzymes, the most effective was cellulase (Trichoderma viride) followed by sequential extraction of the solid pellet using protease type XIV, giving an extraction efficiency of 70%. The complementary data from the electrophoretic fractionation of proteins, and the HPLC separation of Se-species in the proteolytic digests, reveal the existence of large number of selenium-containing compounds in the rye seedling plant biomass. The results showed the complete biotransformation of inorganic selenium into organic forms during germination of the rye seedlings. HPLC-ICP-MS analysis of extracts from the plant biomass did not show the presence of selenate or selenite. At the time of this study, the lack of suitable organic-MS facilities meant that it was not possible to characterise them fully. However, the data does show that a combination of different enzymes, rather than just the commonly-used protease, should be considered when developing an extraction strategy for selenium in different food types to those already reported in the literature. (orig.)

Determination of human and Sprague-Dawley rat trimethylseleonium ion and total selenium urine concentrations from endogenous body selenium pool by neutron activation analysis

International Nuclear Information System (INIS)

Blotcky, A.J.; Claassen, J.P.; Rack, E.P.

1992-01-01

This study determined trimethylselenonium ion [TMSe,(CH 3 ) 3 Se + ] and total organic selenium cationic species urinary excretion values for healthy human subjects and Sprague-Dawley rats fed regular diets. The only source of TMSe was from the endogenous selenium body pool. Total selenium concentration in urine was determined by instrumental neutron activation analysis. TMSe and total selenium cationic species concentrations and percent of total selenium urine excretion were determined by chemical neutron activation analysis and coupled anion-cation exchange chromatography and anion-exchange chromatography, respectively. Within experimental error, mean values for TMSe and cationic species as percent selenium were comparable for both human subjects and Sprague-Dawley rats. This study suggested that TMSe excreated in urine by healthy human subjects and Sprague-Dawley rats fed a normal diet is not a minor but a general metabolite of selenium ingested in a normal diet. (author) 27 refs.; 1 fig.; 2 tabs

Selenium: environmental significance, pollution, and biological treatment technologies.

Science.gov (United States)

Tan, Lea Chua; Nancharaiah, Yarlagadda V; van Hullebusch, Eric D; Lens, Piet N L

2016-01-01

Selenium is an essential trace element needed for all living organisms. Despite its essentiality, selenium is a potential toxic element to natural ecosystems due to its bioaccumulation potential. Though selenium is found naturally in the earth's crust, especially in carbonate rocks and volcanic and sedimentary soils, about 40% of the selenium emissions to atmospheric and aquatic environments are caused by various industrial activities such as mining-related operations. In recent years, advances in water quality and pollution monitoring have shown that selenium is a contaminant of potential environmental concern. This has practical implications on industry to achieve the stringent selenium regulatory discharge limit of 5μgSeL(-1) for selenium containing wastewaters set by the United States Environmental Protection Agency. Over the last few decades, various technologies have been developed for the treatment of selenium-containing wastewaters. Biological selenium reduction has emerged as the leading technology for removing selenium from wastewaters since it offers a cheaper alternative compared to physico-chemical treatments and is suitable for treating dilute and variable selenium-laden wastewaters. Moreover, biological treatment has the advantage of forming elemental selenium nanospheres which exhibit unique optical and spectral properties for various industrial applications, i.e. medical, electrical, and manufacturing processes. However, despite the advances in biotechnology employing selenium reduction, there are still several challenges, particularly in achieving stringent discharge limits, the long-term stability of biogenic selenium and predicting the fate of bioreduced selenium in the environment. This review highlights the significance of selenium in the environment, health, and industry and biotechnological advances made in the treatment of selenium contaminated wastewaters. The challenges and future perspectives are overviewed considering recent

Continued selenium biofortification of carrots and broccoli grown in soils once amended with Se-enriched S. pinnata

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Gary S. Bañuelos

2016-08-01

Full Text Available Selenium (Se biofortification has been practiced in Se-deficient regions throughout the world primarily by adding inorganic sources of Se to the soil. Considering the use of adding organic sources of Se could be useful as an alternative Se amendment for the production of Se-biofortified food crops. In this multi-year micro-plot study, we investigate growing carrots and broccoli in soils that had been previously amended with Se-enriched Stanleya pinnata Pursh (Britton three and four years prior to planting one and two, respectively. Results showed that total and extractable Se concentrations in soils (0-30 cm were 1.65 mg kg-1 and 88 µg L-1, and 0.92 mg kg-1 and 48.6 µg L-1 at the beginning of the growing season for planting one and two, respectively. After each respective growing season, total Se concentrations in the broccoli florets and carrots ranged from 6.99 to 7.83 mg kg-1 and 3.15 to 6.25 mg kg-1 in planting one and two, respectively. In broccoli and carrot plant tissues, SeMet (selenomethionine was the predominant selenoamino acid identified in Se aqueous extracts. In postharvest soils from planting one, phospholipid analyses (PLFA showed that amending the soil with S. pinnata exerted no effect on the microbial biomass, AMF (arbuscular mycorrhizal fungi, actinomycetes and Gram-positive and bacterial PLFA at both 0-5 and 0-30 cm, respectively, three years later. Successfully producing Se-enriched broccoli and carrots three and four years later after amending soil with Se-enriched S. pinnata clearly demonstrates its potential source as an organic Se enriched fertilizer for Se-deficient regions.

Distribution of Selenium and Oxidative Stress in Breast Tumor-Bearing Mice

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Pei-Chung Chen

2013-02-01

Full Text Available The present study investigated the effects of breast tumors on the blood and tissue distribution of essential trace mineral selenium (Se, and oxidative stress status of mice. Female 10-week-old BALB/cByJNarl mice were randomly assigned into control (CNL and breast tumor-bearing (TB groups. TB mice were injected subcutaneously into the right hind thigh with 5 × 106 EMT6 mouse mammary tumor cells. After 22 days, we measured Se concentrations, Se-dependent glutathione peroxidase (GPx activities, and malondialdehyde (MDA products (indicator of oxidative stress in plasma, various tissues, and plasma vascular endothelial growth factor (VEGF concentrations. There were no significant differences in body weights and daily intake between both groups. Compared with the CNL group, TB mice have decreases in plasma Se concentrations and GPx activities, as well as higher plasma VEGF and MDA concentrations. Plasma Se concentrations were also negatively correlated with plasma MDA and VEGF concentrations. Furthermore, tissue Se concentrations and GPx activities in TB animals were lower; whereas the MDA concentrations higher in various tissues including liver, kidney, brain, lung, spleen, and thymic tissues. In conclusion, disruption of Se homeostasis critically reflects oxidative stress in target tissues, thus may increase the risk for progression of breast cancer and metastasis.

Anti-biofilm activity of biogenic selenium nanoparticles and selenium dioxide against clinical isolates of Staphylococcus aureus, Pseudomonas aeruginosa, and Proteus mirabilis.

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Shakibaie, Mojtaba; Forootanfar, Hamid; Golkari, Yaser; Mohammadi-Khorsand, Tayebe; Shakibaie, Mohammad Reza

2015-01-01

The aim of the present study was to investigate the anti-biofilm activity of biologically synthesized selenium nanoparticles (Se NPs) against the biofilm produced by clinically isolated bacterial strains compared to that of selenium dioxide. Thirty strains of Staphylococcus aureus, Pseudomonas aeruginosa, and Proteus mirabilis were isolated from various specimens of the patients hospitalized in different hospitals (Kerman, Iran). Quantification of the biofilm using microtiter plate assay method introduced 30% of S. aureus, 13% of P. aeruginosa and 17% of P. mirabilis isolates as severely adherent strains. Transmission electron micrograph (TEM) of the purified Se NPs (produced by Bacillus sp. MSh-1) showed individual and spherical nano-structure in the size range of 80-220nm. Obtained results of the biofilm formation revealed that selenium nanoparticles inhibited the biofilm of S. aureus, P. aeruginosa, and P. mirabilis by 42%, 34.3%, and 53.4%, respectively, compared to that of the non-treated samples. Effect of temperature and pH on the biofilm formation in the presence of Se NPs and SeO2 was also evaluated. Copyright © 2014 Elsevier GmbH. All rights reserved.

A comparison of the uptake of [75Se]Selenite [75Se] Selenomethionine and [35S]methionine by the tissues of ewes and lambs

International Nuclear Information System (INIS)

Fuss, C.N.; Godwin, K.O.

1975-01-01

The fate of selenium, given as Na 2 75 SeO 3 , or [ 75 Se] selenomethionine, and of [ 35 S]methionine administered intravenously to ewes and lambs, has been examined. The main intention was to follow the incorporation of selenium into protein in a number of tissues, including liver and kidney, and to measure the extent of that incorporation of selenoamino acid, particularly with respect to the administration of selenite. The ewes chosen were lactating ewes with lambs at foot, and the lambs were animals which had been weaned on to fodder low in selenium and were recovering from white muscle disease with selenium therapy. These two experimental situations were chosen as they offered conditions under which selenium incorporation might be considered to be maximal. Entry of isotope into milk was rapid and was greater when 75 Se was given as the selenoamino acid than as selenite. In both ewes and lambs greater amounts of activity, derived from selenite, were bound to plasma proteins than to the proteins of milk. This was particularly evident in samples taken some hours after administration. This ability of the plasma to bind selenium was demonstrated by alkaline dialysis. Small, though significant amounts of selenium, derived from Na 2 75 SeO 3 , were incorporated as selenoamino acids into the proteins of liver, kidney and pancreas, as well as into the proteins of milk and plasma. In ewes, both selenomethionine and selenocystine were identified chromatographically in enzyme digests of defatted liver and kidney. Some differences occurred in the distribution of labelled compounds in organs from lactating ewes and recovering lambs. The incorporation of selenium into protein is discussed briefly in relation to the recent findings of an association between selenium and the enzyme glutathione peroxidase. (author)

Selenium in aquatic biota inhabiting agricultural drains in the Salton Sea Basin, California

Science.gov (United States)

Saiki, Michael K.; Martin, Barbara A.; May, Thomas W.

2012-01-01

Resource managers are concerned that water conservation practices in irrigated farmlands along the southern border of the Salton Sea, Imperial County, California, could increase selenium concentrations in agricultural drainwater and harm the desert pupfish (Cyprinodon macularius), a federally protected endangered species. As part of a broader attempt to address this concern, we conducted a 3-year investigation to collect baseline information on selenium concentrations in seven agricultural drains inhabited by pupfish. We collected water, sediment, selected aquatic food-chain taxa (particulate organic detritus, filamentous algae, net plankton, and midge [Chironomidae] larvae), and two poeciliid fishes (western mosquitofish Gambusia affinis and sailfin molly Poecilia latipinna) for selenium determinations. The two fish species served as ecological surrogates for pupfish, which we were not permitted to sacrifice. Dissolved selenium ranged from 0.70 to 32.8 μg/L, with selenate as the major constituent. Total selenium concentrations in other environmental matrices varied widely among drains, with one drain (Trifolium 18) exhibiting especially high concentrations in detritus, 5.98–58.0 μg Se/g; midge larvae, 12.7–50.6 μg Se/g; mosquitofish, 13.2–20.2 μg Se/g; and mollies, 12.8–30.4 μg Se/g (all tissue concentrations are based on dry weights). Although toxic thresholds for selenium in fishes from the Salton Sea are still poorly understood, available evidence suggests that ambient concentrations of this element may not be sufficiently elevated to adversely affect reproductive success and survival in selenium-tolerant poeciliids and pupfish.

Selenium in aquatic biota inhabiting agricultural drains in the Salton Sea Basin, California.

Science.gov (United States)

Saiki, Michael K; Martin, Barbara A; May, Thomas W

2012-09-01

Resource managers are concerned that water conservation practices in irrigated farmlands along the southern border of the Salton Sea, Imperial County, California, could increase selenium concentrations in agricultural drainwater and harm the desert pupfish (Cyprinodon macularius), a federally protected endangered species. As part of a broader attempt to address this concern, we conducted a 3-year investigation to collect baseline information on selenium concentrations in seven agricultural drains inhabited by pupfish. We collected water, sediment, selected aquatic food-chain taxa (particulate organic detritus, filamentous algae, net plankton, and midge [Chironomidae] larvae), and two poeciliid fishes (western mosquitofish Gambusia affinis and sailfin molly Poecilia latipinna) for selenium determinations. The two fish species served as ecological surrogates for pupfish, which we were not permitted to sacrifice. Dissolved selenium ranged from 0.70 to 32.8 μg/L, with selenate as the major constituent. Total selenium concentrations in other environmental matrices varied widely among drains, with one drain (Trifolium 18) exhibiting especially high concentrations in detritus, 5.98-58.0 μg Se/g; midge larvae, 12.7-50.6 μg Se/g; mosquitofish, 13.2-20.2 μg Se/g; and mollies, 12.8-30.4 μg Se/g (all tissue concentrations are based on dry weights). Although toxic thresholds for selenium in fishes from the Salton Sea are still poorly understood, available evidence suggests that ambient concentrations of this element may not be sufficiently elevated to adversely affect reproductive success and survival in selenium-tolerant poeciliids and pupfish.

Biosynthesis of selenium nanoparticles by Pantoea agglomerans and their antioxidant activity

Energy Technology Data Exchange (ETDEWEB)

Torres, S. K.; Campos, V. L., E-mail: vcampos@udec.cl; Leon, C. G. [Universidad de Concepcion, Laboratorio de Microbiologia Ambiental, Departamento de Microbiologia (Chile); Rodriguez-Llamazares, S. M. [Centro de Investigacion de Polimeros Avanzados (CIPA) (Chile); Rojas, S. M.; Gonzalez, M. [Universidad de Concepcion, Laboratorio de Fisiologia Vascular, Departamento de Fisiologia (Chile); Smith, C. [Universidad de Concepcion, Departamento de Microbiologia (Chile); Mondaca, M. A. [Universidad de Concepcion, Laboratorio de Microbiologia Ambiental, Departamento de Microbiologia (Chile)

2012-11-15

The bio-reduction of selenite (Se (IV)) generates nanoparticles with sizes ranging between 30 and 300 nm. Biologic properties of Se nanoparticles, e.g., antioxidant activity, are dependent on the nanoparticle size; smaller particles have greater activity. In this study, the bio-reduction of selenite by Pantoea agglomerans strain UC-32 under aerobic conditions and room temperature to produce bioactive Se nanoparticles smaller than 100 nm was demonstrated. Isolation and purification of the nanoparticles was performed by alkaline lysis. These purified nanoparticles were stabilized with l-cysteine (4 mM). The visualization and characterization of nanoparticles were performed by transmission electron microscopy, energy dispersive X-ray spectroscopy, and scanning electron microscopy. The antioxidant activity of nanoparticles was determined by production of reactive oxygen species using human umbilical vein endothelial cells. Transmission electron microscopy images showed the accumulation of spherical selenium nanoparticles as intracellular and extracellular deposits. The size of Se nanoparticles varied with incubation time. Amorphous Se nanoparticles with size in the order of 100 nm were obtained before 24 h of incubation; but, at 24 h of incubation, the size of the majority of the nanoparticles was in the desirable order of 100 nm and they were not aggregated. Energy dispersive spectroscopy spectra indicated that nanoparticles were composed entirely of selenium. Antioxidant activity of stabilized selenium nanoparticles demonstrated high antioxidant activity when compared to selenite and selenium nanoparticles without stabilization. Stabilized biologically synthetized selenium (0) nanoparticles with size less than 100 nm have a potential application as a food additive with antioxidant properties relevant to human health.

Biosynthesis of selenium nanoparticles by Pantoea agglomerans and their antioxidant activity

International Nuclear Information System (INIS)

Torres, S. K.; Campos, V. L.; León, C. G.; Rodríguez-Llamazares, S. M.; Rojas, S. M.; González, M.; Smith, C.; Mondaca, M. A.

2012-01-01

The bio-reduction of selenite (Se (IV)) generates nanoparticles with sizes ranging between 30 and 300 nm. Biologic properties of Se nanoparticles, e.g., antioxidant activity, are dependent on the nanoparticle size; smaller particles have greater activity. In this study, the bio-reduction of selenite by Pantoea agglomerans strain UC-32 under aerobic conditions and room temperature to produce bioactive Se nanoparticles smaller than 100 nm was demonstrated. Isolation and purification of the nanoparticles was performed by alkaline lysis. These purified nanoparticles were stabilized with l-cysteine (4 mM). The visualization and characterization of nanoparticles were performed by transmission electron microscopy, energy dispersive X-ray spectroscopy, and scanning electron microscopy. The antioxidant activity of nanoparticles was determined by production of reactive oxygen species using human umbilical vein endothelial cells. Transmission electron microscopy images showed the accumulation of spherical selenium nanoparticles as intracellular and extracellular deposits. The size of Se nanoparticles varied with incubation time. Amorphous Se nanoparticles with size in the order of 100 nm were obtained before 24 h of incubation; but, at 24 h of incubation, the size of the majority of the nanoparticles was in the desirable order of 100 nm and they were not aggregated. Energy dispersive spectroscopy spectra indicated that nanoparticles were composed entirely of selenium. Antioxidant activity of stabilized selenium nanoparticles demonstrated high antioxidant activity when compared to selenite and selenium nanoparticles without stabilization. Stabilized biologically synthetized selenium (0) nanoparticles with size less than 100 nm have a potential application as a food additive with antioxidant properties relevant to human health.

Soil Selenium (Se) Biofortification Changes the Physiological, Biochemical and Epigenetic Responses to Water Stress in Zea mays L. by Inducing a Higher Drought Tolerance.

Science.gov (United States)

Bocchini, Marika; D'Amato, Roberto; Ciancaleoni, Simona; Fontanella, Maria C; Palmerini, Carlo A; Beone, Gian M; Onofri, Andrea; Negri, Valeria; Marconi, Gianpiero; Albertini, Emidio; Businelli, Daniela

2018-01-01

Requiring water and minerals to grow and to develop its organs, Maize ( Zea mays L.) production and distribution is highly rainfall-dependent. Current global climatic changes reveal irregular rainfall patterns and this could represent for maize a stressing condition resulting in yield and productivity loss around the world. It is well known that low water availability leads the plant to adopt a number of metabolic alterations to overcome stress or reduce its effects. In this regard, selenium (Se), a trace element, can help reduce water damage caused by the overproduction of reactive oxygen species (ROS). Here we report the effects of exogenous Se supply on physiological and biochemical processes that may influence yield and quality of maize under drought stress conditions. Plants were grown in soil fertilized by adding 150 mg of Se (sodium selenite). We verified the effects of drought stress and Se treatment. Selenium biofortification proved more beneficial for maize plants when supplied at higher Se concentrations. The increase in proline, K concentrations and nitrogen metabolism in aerial parts of plants grown in Se-rich substrates, seems to prove that Se-biofortification increased plant resistance to water shortage conditions. Moreover, the increase of SeMeSeCys and SeCys2 forms in roots and aerial parts of Se-treated plants suggest resistance strategies to Se similar to those existing in Se-hyperaccumulator species. In addition, epigenetic changes in DNA methylation due to water stress and Se treatment were also investigated using methylation sensitive amplified polymorphism (MSAP). Results suggest that Se may be an activator of particular classes of genes that are involved in tolerance to abiotic stresses. In particular, PSY (phytoene synthase) gene, essential for maintaining leaf carotenoid contents, SDH (sorbitol dehydrogenase), whose activity regulates the level of important osmolytes during drought stress and ADH (alcohol dehydrogenase), whose activity

Soil Selenium (Se) Biofortification Changes the Physiological, Biochemical and Epigenetic Responses to Water Stress in Zea mays L. by Inducing a Higher Drought Tolerance

Science.gov (United States)

Bocchini, Marika; D’Amato, Roberto; Ciancaleoni, Simona; Fontanella, Maria C.; Palmerini, Carlo A.; Beone, Gian M.; Onofri, Andrea; Negri, Valeria; Marconi, Gianpiero; Albertini, Emidio; Businelli, Daniela

2018-01-01

Requiring water and minerals to grow and to develop its organs, Maize (Zea mays L.) production and distribution is highly rainfall-dependent. Current global climatic changes reveal irregular rainfall patterns and this could represent for maize a stressing condition resulting in yield and productivity loss around the world. It is well known that low water availability leads the plant to adopt a number of metabolic alterations to overcome stress or reduce its effects. In this regard, selenium (Se), a trace element, can help reduce water damage caused by the overproduction of reactive oxygen species (ROS). Here we report the effects of exogenous Se supply on physiological and biochemical processes that may influence yield and quality of maize under drought stress conditions. Plants were grown in soil fertilized by adding 150 mg of Se (sodium selenite). We verified the effects of drought stress and Se treatment. Selenium biofortification proved more beneficial for maize plants when supplied at higher Se concentrations. The increase in proline, K concentrations and nitrogen metabolism in aerial parts of plants grown in Se-rich substrates, seems to prove that Se-biofortification increased plant resistance to water shortage conditions. Moreover, the increase of SeMeSeCys and SeCys2 forms in roots and aerial parts of Se-treated plants suggest resistance strategies to Se similar to those existing in Se-hyperaccumulator species. In addition, epigenetic changes in DNA methylation due to water stress and Se treatment were also investigated using methylation sensitive amplified polymorphism (MSAP). Results suggest that Se may be an activator of particular classes of genes that are involved in tolerance to abiotic stresses. In particular, PSY (phytoene synthase) gene, essential for maintaining leaf carotenoid contents, SDH (sorbitol dehydrogenase), whose activity regulates the level of important osmolytes during drought stress and ADH (alcohol dehydrogenase), whose activity

Soil Selenium (Se Biofortification Changes the Physiological, Biochemical and Epigenetic Responses to Water Stress in Zea mays L. by Inducing a Higher Drought Tolerance

Directory of Open Access Journals (Sweden)

Marika Bocchini

2018-03-01

Full Text Available Requiring water and minerals to grow and to develop its organs, Maize (Zea mays L. production and distribution is highly rainfall-dependent. Current global climatic changes reveal irregular rainfall patterns and this could represent for maize a stressing condition resulting in yield and productivity loss around the world. It is well known that low water availability leads the plant to adopt a number of metabolic alterations to overcome stress or reduce its effects. In this regard, selenium (Se, a trace element, can help reduce water damage caused by the overproduction of reactive oxygen species (ROS. Here we report the effects of exogenous Se supply on physiological and biochemical processes that may influence yield and quality of maize under drought stress conditions. Plants were grown in soil fertilized by adding 150 mg of Se (sodium selenite. We verified the effects of drought stress and Se treatment. Selenium biofortification proved more beneficial for maize plants when supplied at higher Se concentrations. The increase in proline, K concentrations and nitrogen metabolism in aerial parts of plants grown in Se-rich substrates, seems to prove that Se-biofortification increased plant resistance to water shortage conditions. Moreover, the increase of SeMeSeCys and SeCys2 forms in roots and aerial parts of Se-treated plants suggest resistance strategies to Se similar to those existing in Se-hyperaccumulator species. In addition, epigenetic changes in DNA methylation due to water stress and Se treatment were also investigated using methylation sensitive amplified polymorphism (MSAP. Results suggest that Se may be an activator of particular classes of genes that are involved in tolerance to abiotic stresses. In particular, PSY (phytoene synthase gene, essential for maintaining leaf carotenoid contents, SDH (sorbitol dehydrogenase, whose activity regulates the level of important osmolytes during drought stress and ADH (alcohol dehydrogenase, whose

Selenium for preventing cancer.

Science.gov (United States)

Vinceti, Marco; Filippini, Tommaso; Del Giovane, Cinzia; Dennert, Gabriele; Zwahlen, Marcel; Brinkman, Maree; Zeegers, Maurice Pa; Horneber, Markus; D'Amico, Roberto; Crespi, Catherine M

2018-01-29

increasing selenium intake - has not been confirmed. As RCT participants have been overwhelmingly male (88%), we could not assess the potential influence of sex or gender.We included 15 additional observational cohort studies (70 in total; over 2,360,000 participants). We found that lower cancer incidence (summary odds ratio (OR) 0.72, 95% CI 0.55 to 0.93; 7 studies, 76,239 participants) and lower cancer mortality (OR 0.76, 95% CI 0.59 to 0.97; 7 studies, 183,863 participants) were associated with the highest category of selenium exposure compared with the lowest. Cancer incidence was lower in men (OR 0.72, 95% CI 0.46 to 1.14, 4 studies, 29,365 men) than in women (OR 0.90, 95% CI 0.45 to 1.77, 2 studies, 18,244 women). Data show a decrease in risk of site-specific cancers for stomach, colorectal, lung, breast, bladder, and prostate cancers. However, these studies have major weaknesses due to study design, exposure misclassification, and potential unmeasured confounding due to lifestyle or nutritional factors covarying with selenium exposure beyond those taken into account in multi-variable analyses. In addition, no evidence of a dose-response relation between selenium status and cancer risk emerged. Certainty of evidence was very low for each outcome. Some studies suggested that genetic factors might modify the relation between selenium and cancer risk - an issue that merits further investigation. Well-designed and well-conducted RCTs have shown no beneficial effect of selenium supplements in reducing cancer risk (high certainty of evidence). Some RCTs have raised concerns by reporting a higher incidence of high-grade prostate cancer and type 2 diabetes in participants with selenium supplementation. No clear evidence of an influence of baseline participant selenium status on outcomes has emerged in these studies.Observational longitudinal studies have shown an inverse association between selenium exposure and risk of some cancer types, but null and direct relations have

Conventional foods, followed by dietary supplements and fortified foods, are the key sources of vitamin D, vitamin B6, and selenium intake in Dutch participants of the NU-AGE study.

Science.gov (United States)

Berendsen, Agnes A M; van Lieshout, Lilou E L M; van den Heuvel, Ellen G H M; Matthys, Christophe; Péter, Szabolcs; de Groot, Lisette C P G M

2016-10-01

With aging, energy needs decrease, necessitating a more nutrient-dense diet to meet nutritional needs. To bridge this gap, the use of nutrient-dense foods, fortified foods, and dietary supplements can be important. This observational study aims to describe current micronutrient intakes of Dutch elderly and to identify the contribution of nutrient-dense foods, fortified foods, and dietary supplements to the intake of micronutrients that are often inadequately consumed in Dutch elderly. Data of 245 Dutch volunteers from the NU-AGE study aged 65 to 80 years were used. Dietary intake was assessed by means of 7-day food records, and dietary supplement use was recorded with an additional questionnaire. Information on fortified foods was obtained from the Dutch Food Composition Table 2011. Nutrient density of foods was evaluated using the Nutrient Rich Food 9.3 score. The percentages of participants not meeting their average requirement were high for vitamin D (99%), selenium (41%), and vitamin B6 (54%) based on conventional foods and also when taking into account fortified foods (98%, 41%, and 27%, respectively) and vitamin and mineral supplements (87%, 36%, and 20%, respectively). Conventional foods were the main source of vitamin D, vitamin B6, and selenium intake (42%, 45%, and 82%, respectively), followed by vitamin and mineral supplements (41%, 44%, and 18%) and fortified foods (17%, 11%, and 1%). Foods with the highest nutrient density contributed most to total vitamin B6 intake only. To optimize nutrient intakes of elderly, combinations of natural food sources, fortified foods, and dietary supplements should be considered. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

[Is plasma selenium correlated to transthyretin levels in critically ill patients?

Science.gov (United States)

Freitas, Renata G B O N; Nogueira, Roberto Jose Negrão; Cozzolino, Silvia Maria Franciscato; Vasques, Ana Carolina Junqueira; Ferreira, Matthew Thomas; Hessel, Gabriel

2017-06-05

Selenium is an essential trace element, but critically ill patients using total parenteral nutrition (PN) do not receive selenium because this mineral is not commonly offered. Threfore, the eval uation of plasma selenium levels is very important for treating or preventing this deficiency. Recent studies have shown that transthyretin may reflect the selenium intake and could be considered a biomarker. However, this issue is still little explored in the literature. This study aims to investigate the correlation of transthyretin with the plasma selenium of critically ill patients receiving PN. This was a prospective cohort study with 44 patients using PN without selenium. Blood samples were carried out in 3 stages: initial, 7th and 14th day of PN. In order to evaluate the clinical condition and the inflammatory process, albumin, C-reactive protein (CRP), transthyretin, creatinine and HDL cholesterol levels were observed. To assess the selenium status, plasma selenium and glutathione peroxidase (GPx) in whole blood were measured. Descriptive analyses were performed and the ANOVA, Mann-Whitney and Spearman's coefficient tests were conducted; we assumed a significance level of 5%. A positive correlation of selenium with the GPx levels (r = 0.46; p = 0.03) was identified. During two weeks, there was a positive correlation of transthyretin with plasma selenium (r = 0.71; p = 0.05) regardless of the CRP values. Transthyretin may have reflected plasma selenium, mainly because the correlation was verified after the acute phase.

Improvement of Selenium Status of Pasture Crops

DEFF Research Database (Denmark)

Nielsen, Gunnar Gissel

1984-01-01

Selenium was applied to pasture crops in a field experiment (1) by foliar application of 10 g Se/ha as selenite in the spring, (2) or by 5 g Se/ha in the spring plus 5 g in early August, (3) as selenite-enriched calcium ammonium nitrate (CAN) at 4 g Se/ha after each cut, and (4) as 4 g Se after...

Kinetic spectrophotometric determination of trace amounts of selenium and vanadium

Energy Technology Data Exchange (ETDEWEB)

Safavi, A.; Sedghy, H.R.; Shams, E. [Dept. of Chemistry, Shiraz Univ. (Iran)

1999-11-01

A sensitive kinetic spectrophotometric method has been developed for the determination of Se(IV) over the range of 45 to 4000 ng in 10 mL of solution. The method is based on the catalytic effect of Se(IV) on the reduction reaction of bromate by hydrazinium dichloride, with subsequent reaction of Ponceau S with products of the above reaction (chlorine and bromine), causing color changing of Ponceau S. Method development includes optimization of time interval for measurement of slope, pH, reagents concentration, and temperature. The optimized conditions yielded a theoretical detection limit of 33 ng/10 mL of solution of Se(IV). The interfering effects were studied and removed. The method was applied to the determination of selenium in spiked water, Kjeldahl tablet, selenium tablet, and shampoo. Vanadium(V) has an inhibition effect on the catalyzed reaction of bromate and hydrazine by selenium. Using this effect, V(V) can be determined in the range of 70 to 2500 ng in 10 mL of solution. The optimization procedure includes pH and selenium concentration. An extraction method was used for interference removal. The method was applied to the determination of vanadium in petroleum. (orig.)

Synergistic Effects of SAM and Selenium Compounds on Proliferation, Migration and Adhesion of HeLa Cells.

Science.gov (United States)

Sun, Licui; Zhang, Jianxin; Yang, Qiu; Si, Yang; Liu, Yiqun; Wang, Qin; Han, Feng; Huang, Zhenwu

2017-08-01

To determine the antitumor activities and molecular mechanism of selenium compounds in HeLa cells. Western blotting was used to detect ERK and AKT activation in HeLa cells induced by selenium compounds selenomethionine (SeMet), methylselenocysteine (MeSeCys) and methylseleninic acids (MeSeA). Using MTT, wound-healing and Matrigel adhesion assays, the antitumor effects of SAM and selenium compounds were evaluated in HeLa cells. MeSeA inhibited ERK and AKT signaling pathways and suppressed the proliferation (peffects compared to the other treatments. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Selenium, selenoproteins and the thyroid gland: interactions in health and disease.

Science.gov (United States)

Schomburg, Lutz

2011-10-18

The trace element selenium is an essential micronutrient that is required for the biosynthesis of selenocysteine-containing selenoproteins. Most of the known selenoproteins are expressed in the thyroid gland, including some with still unknown functions. Among the well-characterized selenoproteins are the iodothyronine deiodinases, glutathione peroxidases and thioredoxin reductases, enzymes involved in thyroid hormone metabolism, regulation of redox state and protection from oxidative damage. Selenium content in selenium-sensitive tissues such as the liver, kidney or muscle and expression of nonessential selenoproteins, such as the glutathione peroxidases GPx1 and GPx3, is controlled by nutritional supply. The thyroid gland is, however, largely independent from dietary selenium intake and thyroid selenoproteins are preferentially expressed. As a consequence, no explicit effects on thyroid hormone profiles are observed in healthy individuals undergoing selenium supplementation. However, low selenium status correlates with risk of goiter and multiple nodules in European women. Some clinical studies have demonstrated that selenium-deficient patients with autoimmune thyroid disease benefit from selenium supplementation, although the data are conflicting and many parameters must still be defined. The baseline selenium status of an individual could constitute the most important parameter modifying the outcome of selenium supplementation, which might primarily disrupt self-amplifying cycles of the endocrine-immune system interface rectifying the interaction of lymphocytes with thyroid autoantigens. Selenium deficiency is likely to constitute a risk factor for a feedforward derangement of the immune system-thyroid interaction, while selenium supplementation appears to dampen the self-amplifying nature of this derailed interaction.

A systematic approach to the accurate quantification of selenium in serum selenoalbumin by HPLC-ICP-MS

International Nuclear Information System (INIS)

Jitaru, Petru; Goenaga-Infante, Heidi; Vaslin-Reimann, Sophie; Fisicaro, Paola

2010-01-01

In this paper, two different methods are for the first time systematically compared for the determination of selenium in human serum selenoalbumin (SeAlb). Firstly, SeAlb was enzymatically hydrolyzed and the resulting selenomethionine (SeMet) was quantified using species-specific isotope dilution (SSID) with reversed phase-HPLC (RP-HPLC) hyphenated to (collision/reaction cell) inductively coupled plasma-quadrupole mass spectrometry (CRC ICP-QMS). In order to assess the enzymatic hydrolysis yield, SeAlb was determined as an intact protein by affinity-HPLC (AF-HPLC) coupled to CRC ICP-QMS. Using this approach, glutathione peroxidase (GPx) and selenoprotein P (SelP) (the two selenoproteins present in serum) were also determined within the same chromatographic run. The levels of selenium associated with SeAlb in three serum materials, namely BCR-637, Seronorm level 1 and Seronorm level 2, obtained using both methods were in a good agreement. Verification of the absence of free SeMet, which interferes with the SeAlb determination (down to the amino acid level), in such materials was addressed by analyzing the fraction of GPx, partially purified by AF-HPLC, using RP-HPLC (GPx only) and size exclusion-HPLC (SE-HPLC) coupled to CRC ICP-QMS. The latter methodology was also used for the investigation of the presence of selenium species other than the selenoproteins in the (AF-HPLC) SelP and SeAlb fractions; the same selenium peaks were detected in both control and BCR-637 serum with a difference in age of ca. 12 years. It is also for the first time that the concentrations of selenium associated with SeAlb, GPx and SelP species in such commercially available serums (only certified or having indicative levels of total selenium content) are reported. Such indicative values can be used for reference purposes in future validation of speciation methods for selenium in human serum and/or inter-laboratory comparisons.

A systematic approach to the accurate quantification of selenium in serum selenoalbumin by HPLC-ICP-MS

Energy Technology Data Exchange (ETDEWEB)

Jitaru, Petru, E-mail: Petru.Jitaru@lne.fr [Laboratoire National de Metrologie et d' Essais (LNE), Department of Biomedical and Inorganic Chemistry, 1 rue Gaston Boissier, 75015 Paris (France); Goenaga-Infante, Heidi [LGC Limited, Queens Road, Teddington, TW11 OLY, Middlesex (United Kingdom); Vaslin-Reimann, Sophie; Fisicaro, Paola [Laboratoire National de Metrologie et d' Essais (LNE), Department of Biomedical and Inorganic Chemistry, 1 rue Gaston Boissier, 75015 Paris (France)

2010-01-11

In this paper, two different methods are for the first time systematically compared for the determination of selenium in human serum selenoalbumin (SeAlb). Firstly, SeAlb was enzymatically hydrolyzed and the resulting selenomethionine (SeMet) was quantified using species-specific isotope dilution (SSID) with reversed phase-HPLC (RP-HPLC) hyphenated to (collision/reaction cell) inductively coupled plasma-quadrupole mass spectrometry (CRC ICP-QMS). In order to assess the enzymatic hydrolysis yield, SeAlb was determined as an intact protein by affinity-HPLC (AF-HPLC) coupled to CRC ICP-QMS. Using this approach, glutathione peroxidase (GPx) and selenoprotein P (SelP) (the two selenoproteins present in serum) were also determined within the same chromatographic run. The levels of selenium associated with SeAlb in three serum materials, namely BCR-637, Seronorm level 1 and Seronorm level 2, obtained using both methods were in a good agreement. Verification of the absence of free SeMet, which interferes with the SeAlb determination (down to the amino acid level), in such materials was addressed by analyzing the fraction of GPx, partially purified by AF-HPLC, using RP-HPLC (GPx only) and size exclusion-HPLC (SE-HPLC) coupled to CRC ICP-QMS. The latter methodology was also used for the investigation of the presence of selenium species other than the selenoproteins in the (AF-HPLC) SelP and SeAlb fractions; the same selenium peaks were detected in both control and BCR-637 serum with a difference in age of ca. 12 years. It is also for the first time that the concentrations of selenium associated with SeAlb, GPx and SelP species in such commercially available serums (only certified or having indicative levels of total selenium content) are reported. Such indicative values can be used for reference purposes in future validation of speciation methods for selenium in human serum and/or inter-laboratory comparisons.

Glassy selenium at high pressure: Le Chatelier's principle still works

Science.gov (United States)

Brazhkin, V. V.; Tsiok, O. B.

2017-10-01

Selenium is the only easily vitrified elementary substance. Numerous experimental studies of glassy Se (g -Se) at high pressures show a large spread in the data on the compressibility and electrical resistivity of g -Se. Furthermore, H. Liu et al. [Proc. Natl. Acad. Sci. USA 105, 13229 (2008), 10.1073/pnas.0806857105] have arrived at the surprising conclusion that the volume of glass increases during pressure-induced crystallization. We have performed high-precision measurements of the specific volume and electrical resistivity of glassy selenium (g -Se) at high hydrostatic pressures up to 9 GPa. The measured bulk modulus at normal pressure is B =(9.0 5 ±0.15 ) GPa and its pressure derivative is BP'=6.4 ±0.2 . In the pressure range P <3 GPa, glassy selenium has an anomalously large negative second derivative of the bulk modulus. The electrical resistivity of g -Se decreases almost exponentially with increasing pressure and reaches 20 Ω cm at a pressure of 8.75 GPa. The inelastic behavior and weak relaxation of the volume for g -Se begin at pressures above 3.5 GPa; the volume and logarithm of the electrical resistivity relax significantly (logarithmically with the time) at pressures above 8 GPa. Bulk measurements certainly indicate that the volume of g -Se glass in the crystallization pressure range is larger than the volumes of both appearing crystalline phases (by 2% and 4%). Therefore, the "volume expansion phenomenon" suggested in [H. Liu et al., Proc. Natl. Acad. Sci. USA 105, 13229 (2008), 10.1073/pnas.0806857105] is not observed, and the pressure-induced crystallization of glassy selenium is consistent with the laws of thermodynamics.

Toxicity of selenium (Na sub 2 SeO sub 3 ) and mercury (HgCl sub 2 ) on the planarian Dugesia gonocephala

Energy Technology Data Exchange (ETDEWEB)

Congiu, A.M.; Casu, S.; Ugazio, G. (Istituto di Genetica (Italy))

1989-10-01

The toxicity of selenium (Na{sub 2}SeO{sub 3}) and mercury (HgCl{sub 2}) was determined by using a freshwater planarian which is particularly sensitive to pollution, and belongs to a fissiparous breed of Dugesia gonocephala. The mortality and fissiparity frequency of the subjects were studied. They were exposed to intense treatments (48 hours) or for medium to long periods of time (21 days) to either the single compounds or a combination of both, and were fed or fasting. The lethal effect of sodium selenite is correlated to the food intake, whereas the toxicity of mercurous chloride is probably the result of a fixative effect which does not depend on feeding. The 21-day treatment with the first compound has a non-negligible lethal effect which is probably due to an accumulation phenomenon. At doses where an antioxidant effect prevails, fissiparity is stimulated. On the other hand, the second compound reduces reproduction frequency to half the base values. Compared to the Paracentrotus lividus, the Dugesia gonocephala offers various advantages concerning toxicological experiments; besides being easier to handle in the laboratory, it is available all year round and is not subject to seasonal cycles. It is also more susceptible to the toxic effect of mercury, which is a common and highly toxic pollutant, than the sea urchin.

Nanocrystalline hydroxyapatite doped with selenium oxyanions: A new material for potential biomedical applications

Energy Technology Data Exchange (ETDEWEB)

Kolmas, Joanna, E-mail: joanna.kolmas@wum.edu.pl [Medical University of Warsaw, Faculty of Pharmacy, Department of Inorganic and Analytical Chemistry, ul. Banacha 1, 02-097 Warsaw (Poland); Oledzka, Ewa; Sobczak, Marcin [Medical University of Warsaw, Faculty of Pharmacy, Department of Inorganic and Analytical Chemistry, ul. Banacha 1, 02-097 Warsaw (Poland); Nałęcz-Jawecki, Grzegorz [Medical University of Warsaw, Faculty of Pharmacy, Department of Environmental Health Sciences, ul. Banacha 1, 02-097 Warsaw (Poland)

2014-06-01

Selenium-substituted hydroxyapatites containing selenate SeO{sub 4}{sup 2−} or selenite SeO{sub 3}{sup 2−} ions were synthesized using a wet precipitation method. The selenium content was determined by atomic absorbance spectrometry. The raw, unsintered powders were also characterized using powder X-ray diffraction, middle-range FT-IR spectroscopy and transmission electron microscopy with energy-dispersive X-ray spectroscopic microanalysis. The synthesized apatites were found to be pure and nanocrystalline with a crystal size similar to that in bone mineral. The incorporation of selenium oxyanions into the crystal lattice was confirmed. The toxicity of hydroxyapatites containing selenite or selenate ions was evaluated with a protozoan assay and bacterial luminescence test. - Highlights: • We synthesized and analyzed hydroxyapatites doped with selenium oxyanions. • We used various analytical methods, i.e. XRD, TEM, AAS and FT-IR. • We confirmed incorporation of SeO{sub 3}{sup 2−} and SeO{sub 4}{sup 2−} into the crystal lattice. • The toxicity of the materials was studied.

Selenium determination in biological materials by neutron activation analysis - statistical comparison between the use of {sup 77m} Se (t{sub 1/2} 17.45 s) and {sup 75} Se (t{sub 1/2} = 119,8 d); Determinacao de selenio em materiais biologicos por analise por ativacao com neutrons - comparacao estatistica entre o uso do {sup 77m} Se (t{sub 1/2} 17.45s) e {sup 75} Se (t{sub 1/2} = 119,8d)

Energy Technology Data Exchange (ETDEWEB)

Catharino, Marilia G.M.; Vasconcelos, Marina B.A. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)

2002-07-01

Selenium is nowadays considered to be an essential trace element in human diet. The most extensively studied biochemical role of this element is related to its participation in the composition of glutathione peroxidase. This enzyme acts as an antioxidant for the free radicals formed in the human body. In the present work, selenium was determined by INAA in reference materials ('Human hair' IAEA-085, 'Human hair' IAEA-086, 'Dogfish Liver' DOLT-1 e 'Dogfish Muscle' DORM-1) and in toenails and vitamin supplement, using the short-lived radioisotope {sup 77m} Se. The usual method, which utilizes long- lived {sup 75} Se, was also employed, in order to make a comparative study. A statistical test was applied for this comparison. It was verified that the average concentrations of selenium, in the reference materials and in the samples analyzed, do not differ statistically at a significance level of 0.05, which indicates the applicability of the short-lived {sup 77m} Se for INAA of the matrixes studied. (author)

Loss of selenium in drying and storage of agronomic plant species

DEFF Research Database (Denmark)

Nielsen, Gunnar Gissel

1970-01-01

In two experiments with Se75, loss of selenium from agricultural species was noted during both drying and storage. The loss of selenium during drying was to some extent overshadowed by the influence of self-absorption caused by the water in the fresh material. The results showed that even plant...... material of non-indicator plantslose volatile selenium at drying temperatures of 60°C or higher, and in some cases even at temperatures below 60°C. The results also showed that storage as briquettes gives the lowest storage loss of selenium....

No evidence of selenosis from a selenium-rich diet in the Brazilian Amazon.

Science.gov (United States)

Lemire, Mélanie; Philibert, Aline; Fillion, Myriam; Passos, Carlos José Sousa; Guimarães, Jean Rémy Davée; Barbosa, Fernando; Mergler, Donna

2012-04-01

Selenium (Se) is an essential element and a well-known anti-oxidant. In the Lower Tapajós River region of the Brazilian Amazon, biomarkers of Se range from normal to very high. The local traditional diet includes important Se sources such as Brazil nuts, chicken, game meat and certain fish species. Some studies have reported alterations in keratin structure, gastrointestinal problems and paresthesia in populations with high Se intake. The objective of the present study was to evaluate cutaneous and garlic odor of the breath signs and sentinel symptoms of Se toxicity (selenosis) in relation to Se status in communities along the Tapajós River. Participants (N=448), aged 15-87 years, were recruited from 12 communities. Se concentrations were measured in blood (B-Se) and plasma (P-Se) by ICP-MS. A nurse performed an examination of the hair, nails, skin and breath for signs of Se toxicity. Interview-administered questionnaires were used to collect information on socio-demographics, medical history and possible symptoms of Se toxicity. In this population, the median levels of B-Se and P-Se were 228.4 μg/L (range 103.3-1500.2 μg/L) and 134.8 μg/L (range 53.6-913.2 μg/L) respectively. Although B-Se and P-Se surpassed concentrations considered toxic (B-Se: 1000 μg/L (U.S. EPA, 2002)), no dermal or breath signs or symptoms of Se toxicity were associated with the biomarkers of Se status. In the present study population, where Se intake is mostly from traditional diet, there is no evidence of selenosis. These findings support the need to re-assess Se toxicity considering factors such as the chemical form of Se exposure, route of exposure (inhaled versus ingested), co-exposures to toxic elements such as mercury. Considering the current food transition towards a western diet in the Amazon, further studies should address the possible association between high Se status and cardiometabolic health in this study population. Copyright © 2011 Elsevier Ltd. All rights reserved.

Serum selenium concentration is associated with metabolic factors in the elderly: a cross-sectional study

Directory of Open Access Journals (Sweden)

Huang Hui-Ying

2010-05-01

Full Text Available Abstract Background Selenium is an essential micronutrient known for its antioxidant function. However, the association of serum selenium with lipid profiles and fasting glucose are inconsistent in populations with average intake of selenium. Furthermore, there were few studies conducted specifically for the elderly. This study examined the relationship of serum selenium concentration with serum lipids and fasting glucose in the Taiwanese elderly population. Methods This was a cross-sectional study of 200 males and females aged 65-85 years (mean 71.5 ± 4.6 years from Taipei, Taiwan. Serum selenium was measured by inductively coupled plasma-mass spectrometer. The association between serum selenium and metabolic factors was examined using a multivariate linear regression analysis after controlling several confounders. Results The mean serum selenium concentration was 1.14 μmol/L, without significant difference between sexes. Total cholesterol, triglycerides, and LDL cholesterol increased significantly with serum selenium concentration (P P P P Conclusions Total cholesterol, triglycerides, and LDL cholesterol, and fasting serum glucose concentrations increased significantly with serum selenium concentration in the Taiwanese elderly. The underlying mechanism warrants further research.

Enriched selenium and its effects on growth and biochemical composition in Lactobacillus bulgaricus.

Science.gov (United States)

Xia, Shu Kai; Chen, Long; Liang, Jun Qing

2007-03-21

Se-enriched Lactobacillus bulgaricus (L. bulgaricus) was generated by administration of sodium selenite (0, 1, 4, 8, 16, 32, and 64 mg/L, respectively) in MRS medium and enriched selenium manifestation in L. bulgaricus was investigated using transmission electron microscopy and energy-dispersive X-ray spectrometry and alterations of essential elements and amino acids in the organism were evaluated. We demonstrate that administration of sodium selenite in the dosage of 1-16 mg/L is suitable for selenium enrichment in L. bulgaricus and can enhance nutritive value in the organism by elevating the contents of essential elements including P, Mg, Mn, Zn, Ca, and total amino acids as well as reducing selenite to insoluble elemental selenium, an electron-dense and amorphous Se (0) granule, thereby depositing it both in the cytoplasm and in the extracellular space of L. bulgaricus. Thus, Se-enriched Lactobacillus can provide a potential dietary source of nontoxic selenium and functional regulator used for food and medical industry.

Selenium as an alternative peptide label - comparison to fluorophore-labelled penetratin

DEFF Research Database (Denmark)

Hyrup Møller, Laura; Bahnsen, Jesper Søborg; Nielsen, Hanne Mørck

2015-01-01

lysates, primarily the intact peptide (PenMSe, TAMRA-PenMSe or TAMRA-Pen) was observed. Selenium labelling caused minimal alteration of the physicochemical properties of the peptide and allowed for absolute quantitative determination of cellular uptake by inductively coupled plasma mass spectrometry......In the present study, the impact on peptide properties of labelling peptides with the fluorophore TAMRA or the selenium (Se) containing amino acid SeMet was evaluated. Three differently labelled variants of the cell-penetrating peptide (CPP) penetratin (Pen) were synthesized, PenMSe, TAMRA....... Selenium is thus proposed as a promising alternative label for quantification of peptides in general, altering the properties of the peptide to a minor extent as compared to commonly used peptide labels....

Mixed Surfactant Template Method for Preparation of Nanometer Selenium

Directory of Open Access Journals (Sweden)

Zhi-Lin Li

2009-01-01

Full Text Available Selenium nanoparticles have been synthesized in an aqueous solution by using sodium dodecyl sulfate and polyvinyl alcohol as a soft template. The factors on synthesis, such as reaction time, concentration of reactants and ultrasonic irradiation were studied. The uniform stable selenium nanospheres were obstained in the conditions of 1.0 (mass fraction sodium dodecyl sulfate, 1.0 (mass fraction polyvinyl alcohol, n(Vc:n(H2SeO3=7:1 and 7 minutes after the initiation of the reaction at room temperature. The average particle size of selenium is about 30 nm. The product was characterized by UV and TEM. Finally the applications of the red element nanometer selenium in anti-older cosmetics are presented.

Effects of cyanide on selenium metabolism in rats

International Nuclear Information System (INIS)

Beilstein, M.A.; Whanger, P.D.

1984-01-01

Adult male rats were given drinking water containing either 0 or 150 ppm cyanide for 2 weeks. They were then injected with 5 microCi 75 Se-selenite, and excretion of radioactivity in urine and feces was determined. No difference in excretion of 75 Se occurred during the rapid phase, but the cyanide-treated rats (T1/2 28 days) excreted significantly more 75 Se in urine than control (T1/2 38 days) rats. Cyanide had no effect on excretion of 75 Se in feces or on the distribution of 75 Se in cytosolic proteins in liver, kidney, muscle or testes. In a second experiment weanling male rats were given water with either 0 or 150 ppm cyanide and were killed for glutathione peroxidase assay and selenium analysis in blood, kidney, liver, muscle and testes after 3, 6 or 9 weeks of treatment. Glutathione peroxidase activity and selenium concentrations were significantly reduced by cyanide in all tissues except testes

Biogeochemistry of selenium isotopes: processes, cycling and paleoenvironmental applications

NARCIS (Netherlands)

Mitchell, K.A.

2012-01-01

Selenium (Se) is an essential trace element, which, with multiple oxidation states and six stable isotopes, has been suggested as a potentially powerful environmental tracer and paleoenvironmental proxy. Chapter 1 provides a literature review of the Se cycle. While the Se cycle shares some

Selenium accumulation in plants--phytotechnological applications and ecological implications.

Science.gov (United States)

Valdez Barillas, José Rodolfo; Quinn, Colin F; Pilon-Smits, Elizabeth A H

2011-01-01

Selenium (Se) is an essential trace element for many organisms including humans, yet toxic at higher levels. Both Se deficiency and toxicity are problems worldwide. Since plants readily accumulate and volatilize Se, they may be used both as a source of dietary Se and for removing excess Se from the environment. Plant species differ in their capacity to metabolize and accumulate Se, from non-Se accumulators ( 1,000 mg Se/kg DW). Here we review plant mechanisms of Se metabolism in these various plant types. We also summarize results from genetic engineering that have led to enhanced plant Se accumulation, volatilization, and/or tolerance, including field studies. Before using Se-accumulating plants at a large scale we need to evaluate the ecological implications. Research so far indicates that plant Se accumulation significantly affects the plant's ecological interactions below and above ground. Selenium canprotect plants from fungal pathogens and from a variety of invertebrate and vertebrate herbivores, due to both deterrence and toxicity. However, specialist (Se-tolerant herbivores), detritivores and endophytes appear to utilize Se hyperaccumulator plants as a resource. These findings are relevant for managing phytoremediation of Se and similar elements.

75Se-labelled cortisol in analysis by competition

International Nuclear Information System (INIS)

Glover, J.S.; Chambers, V.E.M.

1975-01-01

Selenium 75 has nuclear properties very suitable for the labelling of steroids used as tracers in competition analysis. A method of preparing a selenium-labelled cortisol derivative, 75 Se methylselenoprednisolone, is described. A system based on bonding competition between plasma cortisol and 75 Se methylselenoprednisolone on transcortine was studied, the separation taking place on a Sephadex adsorbant. An early analysis with highly stable reagents was achieved [fr

SPECIATION OF SELENIUM AND ARSENIC COMPOUNDS BY CAPILLARY ELECTROPHORESIS WITH HYDRODYNAMICALLY MODIFIED ELECTROOSMOTIC FLOW AND ON-LINE REDUCTION OF SELENIUM(VI) TO SELENIUM(IV) WITH HYDRIDE GENERATION INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRIC DETECTION

Science.gov (United States)

Capillary electrophoresis (CE) with hydride generation inductively coupled plasma mass spectrometry was used to determine four arsenicals and two selenium species. Selenate (SeVI) was reduced on-line to selenite (SeIV') by mixing the CE effluent with concentrated HCl. A microporo...

Selenium toxicity: cause and effects in aquatic birds

Science.gov (United States)

Spallholz, J.E.; Hoffman, D.J.

2002-01-01

There are several manners in which selenium may express its toxicity: (1) an important mechanism appears to involve the formation of CH3Se- which either enters a redox cycle and generates superoxide and oxidative stress, or forms free radicals that bind to and inhibit important enzymes and proteins. (2) Excess selenium as selenocysteine results in inhibition of selenium methylation metabolism. As a consequence, concentrations of hydrogen selenide, an intermediate metabolite, accumulate in animals and are hepatotoxic, possibly causing other selenium-related adverse effects. (3) It is also possible that the presence of excess selenium analogs of sulfur-containing enzymes and structural proteins play a role in avian teratogenesis. l-selenomethionine is the most likely major dietary form of selenium encountered by aquatic birds, with lesser amounts of l-selenocysteine ingested from aquatic animal foods. The literature is suggestive that l-selenomethionine is not any more toxic to adult birds than other animals. l-Selenomethionine accumulates in tissue protein of adult birds and in the protein of egg white as would be expected to occur in animals. There is no suggestion from the literature that the levels of l-selenomethionine that would be expected to accumulate in eggs in the absence of environmental concentration of selenium pose harm to the developing embryo. For several species of aquatic birds, levels of Se as selenomethionine in the egg above 3 ppm on a wet weight basis result in reduced hatchability and deformed embryos. The toxicity of l-selenomethionine injected directly into eggs is greater than that found from the entry of l-selenomethionine into the egg from the normal adult diet. This suggests that there is unusual if not abnormal metabolism of l-selenomethionine in the embryo not seen when l-selenomethionine is present in egg white protein where it likely serves as a source of selenium for glutathione peroxidase synthesis in the developing aquatic chick.

Dietary Selenium Deficiency or Excess Reduces Sperm Quality and Testicular mRNA Abundance of Nuclear Glutathione Peroxidase 4 in Rats.

Science.gov (United States)

Zhou, Ji-Chang; Zheng, Shijie; Mo, Junluan; Liang, Xiongshun; Xu, Yuanfei; Zhang, Huimin; Gong, Chunmei; Liu, Xiao-Li; Lei, Xin Gen

2017-10-01

Background: Glutathione peroxidase (GPX) 4 and selenoprotein P (SELENOP) are abundant, and several variants are expressed in the testis. Objective: We determined the effects of dietary selenium deficiency or excess on sperm quality and expressions of GPX4 and SELENOP variants in rat testis and liver. Methods: After weaning, male Sprague-Dawley rats were fed a Se-deficient basal diet (BD) for 5 wk until they were 9 wk old [mean ± SEM body weight (BW) = 256 ± 5 g]. They were then fed the BD diet alone (deficient) or with 0.25 (adequate), 3 (excess), or 5 (excess) mg Se/kg for 4 wk. Testis, liver, blood, and semen were collected to assay for selenoprotein mRNA and protein abundances, selenium concentration, GPX activity, 8-hydroxy-deoxyguanosine concentration, and sperm quality. Results: Dietary selenium supplementations elevated ( P selenium concentrations and GPX activities. Compared with those fed BD + 0.25 mg Se/kg, rats fed BD showed lower ( P selenium-adequate group. Compared with the selenium-adequate group, dietary selenium deficiency (BD) or excess (BD + 3 or 5 mg Se/kg) resulted in 45-77% lower ( P selenium concentrations in similar ways to sperm parameters and may be used as a sensitive marker to assess appropriate Se status for male function. © 2017 American Society for Nutrition.

Potential Moderating Effects of Selenium on Mercury Uptake and Selenium:Mercury Molar Ratios in Fish From Oak Ridge and Savannah River Site - 12086

Energy Technology Data Exchange (ETDEWEB)

Burger, Joanna; Gochfeld, Michael; Donio, Mark [Division of Life Sciences, Rutgers University, 604 Allison Road, Piscataway, New Jersey 08854-8082 (United States); Environmental and Occupational Medicine, UMDNJ-Robert Wood Johnson Medical School, Piscataway, New Jersey 08854 (United States); Jeitner, Christian; Pittfield, Taryn [Division of Life Sciences, Rutgers University, 604 Allison Road, Piscataway, New Jersey 08854-8082 (United States); Consortium for Risk Evaluation with Stakeholder Participation (CRESP), Rutgers University and Vanderbilt University, Nashville, Tennessee 37235 (United States)

2012-07-01

Mercury contamination is an important remediation issue at the U.S. Department of Energy's (DOE) Oak Ridge Reservation and to a lesser extent at other DOE sites because of the hazard it presents, potential consequences to humans and eco-receptors, and completed pathways, to offsite receptors. Recent work has emphasized that selenium might ameliorate the toxicity of mercury, and we examine the selenium:mercury (Se:Hg) molar ratios in fish from Oak Ridge, and compare them to Se:Hg molar ratios in fish from the Savannah River. Selenium/mercury molar ratios varied considerably among and within fish species. There was considerable variation in the molar ratios for individual fish (as opposed to mean ratios by species) for freshwater fish from both sites. The inter-individual variation in molar ratios indicates that such that the molar ratios of mean Se and Hg concentrations may not be representative. Even for fish species with relatively low mercury levels, some individual fish have molar ratios less than unity, the value sometime thought to be protective. Selenium levels varied narrowly regardless of fish size, consistent with homeostatic regulation of this essential trace element. The data indicate that considerable attention will need to be directed toward variations and variances, as well as the mechanisms of the interaction of selenium and mercury, before risk assessment and risk management policies can use this information to manage mercury pollution and risk. Even so, if there are high levels of selenium in the fish from Poplar Creek on Oak Ridge, then the potential exists for some amelioration of adverse health effects, on the fish themselves, predators that eat them, and people who consume them. This work will aid DOE because it will allow managers and scientists to understand another aspect that affects fate and transport of mercury, as well as the potential effects of methylmercury in fish for human and ecological receptors. The variability within fish

Comparative effect of organic and inorganic selenium supplementation on selenium status in camel

Directory of Open Access Journals (Sweden)

B. Faye

2014-04-01

Full Text Available Selenium deficiency is widely described in livestock from the Arabian Peninsula, notably in the camel, and selenium supplementation is based on cattle or horse requirements, usually with sodium selenite product. In order to test the effect of organic Se supplementation vs inorganic Se, 24 pregnant camels were subjected to 3 treatment groups starting one month before delivery (control without Se, non-organic bolus, organic Se. Blood, milk and feces samples were collected from one month before delivery to 3 months of lactation. At delivery, the organic group had a significant higher Se concentration (P < 0.01 in serum (8.21 ± 1.38 μg/100 mL and in colostrum (7.27 ± 2.89 μg/100 mL than in inorganic group (3.90 ± 0.68 and 3.72 ± 0.71, respectively and than in control group (5.45 ± 2.38 and 2.70 ± 0.66, respectively. In calf serum, the Se concentration was significantly higher (P < 0.001 in the two supplemented groups (6.32 ± 2.81 and 5.99 ± 3.31 μg/100 mL in organic and inorganic groups, respectively than in control (3.42 ± 1.41 μg/100 mL. The Se in mother serum decreased after parturition but was highly correlated to Se serum in calf and to Se fecal excretion. Se in milk was lower than in colostrum in all groups (P < 0.01. Treatments had no significant effect on somatic cell count. This study revealed that organic supplementation in camel appeared more efficient.

HORMONAL REGULATION OF SELENIUM ACCUMULATION BY PLANTS

Directory of Open Access Journals (Sweden)

N. A. Golubkina

2015-01-01

Full Text Available Hormonal regulation is considered to be a unique mechanism controlling growth and development of living organism. The review discusses the correlations between pant hormonal status of non-accumulators and hyper-accumulators of Se with the accumulation levels of this microelement. The phenomenon of stimulation and redistribution of selenium as a result of phytohormone treatment, the peculiarities of phytohormones effect among different species and cultivars, and influence of plant sexualization on selenium accumulation are described in article. Data of hormonal regulation of selenium level for spinach, garlic, perennial onion, Brassica chinenesis and Valeriana officialis are presented in the review.

Selenium transformation in coal mine spoils: Its environmental impact assessment

Energy Technology Data Exchange (ETDEWEB)

Harness, J.; Atalay, A.; Koll, K.J.; Zhang, H.; Maggon, D.

1991-12-31

The objective of this program was to conduct an environmental impact assessment study for selenium from coal mine spoils. The use of in-situ lysimetry to predict selenium speciation, transformation, and mobility under natural conditions was evaluated. The scope of the study was to construct and test field-scale lysimeter and laboratory mini-column to assess mobility and speciation of selenium in coal mine overburden and soil systems; to conduct soil and groundwater sampling throughout the state of Oklahoma for an overall environmental impact assessment of selenium; and to conduct an in-depth literature review on the solubility, speciation, mobility, and toxicity of selenium from various sources. Groundwater and surface soil samples were also collected from each county in Oklahoma. Data collected from the lysimeter study indicated that selenium in the overburden of the abandoned mine site was mainly found in the selenite form. The amount of selenite found was too low and immobile to be of concern to the environment. The spoil had equilibrated long enough (over 50 years) that most of the soluble forms of selenium have already been lost. Examination of the overburden indicated the presence of pyrite crystals that precipitated over time. The laboratory mini-column study indicated that selenite is quite immobile and remained on the overburden material even after leaching with dilute acid. Data from groundwater samples indicated that based on the current permissible level for selenium in groundwater (0.01 mg Se/L), Oklahoma groundwater is widely contaminated with the element. However, according to the new regulation (0.05 mg Se/L), which is to be promulgated in 1992, only 9 of the 77 counties in the state exceed the limit.

Copper and selenium supplementation in the diet of Brangus steers on the nutritional characteristics of meat

Directory of Open Access Journals (Sweden)

Arlindo Saran Netto

2013-01-01

Full Text Available Twenty-eight Brangus cattle were used to determine the effect of copper and selenium supplementation on the carcass characteristics, fatty acid composition of the longissimus dorsi muscle and on the copper and selenium concentrations in the liver. The treatments were: no supplementation of copper or selenium; 2 mg Se/kg DM as sodium selenite; 40 mg Cu/kg DM as copper sulfate; and 2 mg Se/kg DM as sodium selenite and 40 mg Cu/kg DM as copper sulfate. The fat thickness, rib eye area and fatty acid composition of the longissimus dorsi muscle were not affected by treatments. There was no effect on carcass yield and cooling loss with the supplementation of copper, selenium or selenium × copper in the levels studied. For the ether extract concentration in the longissimus dorsi muscle, no differences were found according to the treatments with selenium, copper or selenium × copper. The treatments with selenium and selenium × copper showed higher selenium concentrations in the liver than the control and copper treatments. For the copper concentration in the liver, the copper and selenium × copper treatments showed higher values than the control and selenium treatments. Despite the little effect on the meat composition, the results of this experiment demonstrate no interaction between selenium and copper in the levels studied.

Sweet chemistry: a green way for obtaining selenium nanoparticles active against cancer cells

International Nuclear Information System (INIS)

Vieira, Adriana P.; Stein, Erika M.; Ferreira, Ana Maria D.C.; Colepicolo, Pio; Andreguetti, Daniel X.; Cebrián-Torrejón, Gerardo; Doménech-Carbó, Antonio

2017-01-01

We present an environment friendly synthesis of selenium nanoparticles and the study of their cytotoxic activity against uterine sarcoma cancer and fibroblasts cells. Amorphous selenium (a-SeNPs) and trigonal selenium (t-SeNPs) were synthesized using D-fructose as the reducing agent and characterized by high-resolution transmission electron microscopy (HRTEM), energy dispersive X-ray spectroscopy (EDX), powder X-ray diffraction analysis (XRD), inductively coupled plasma optical emission spectrometry (ICP OES), dynamic light scattering (DLS) to obtain zeta potential values and cyclic voltammetry (CV). Particularly, a-SeNPs presented high toxicity toward the resistant cancer cell line MES-SA/Dx5 and its parental MES-SA line. However, they are not toxic against P4 fibroblast cells in comparative studies. (author)

Sweet chemistry: a green way for obtaining selenium nanoparticles active against cancer cells

Energy Technology Data Exchange (ETDEWEB)

Vieira, Adriana P.; Stein, Erika M.; Ferreira, Ana Maria D.C.; Colepicolo, Pio, E-mail: apiresvieira@gmail.com [Universidade de São Paulo (USP), São Paulo-SP (Brazil); Andreguetti, Daniel X.; Cebrián-Torrejón, Gerardo; Doménech-Carbó, Antonio [Departament de Química Analítica, Facultat de Química, Universitat de València, Valencia (Spain)

2017-07-01

We present an environment friendly synthesis of selenium nanoparticles and the study of their cytotoxic activity against uterine sarcoma cancer and fibroblasts cells. Amorphous selenium (a-SeNPs) and trigonal selenium (t-SeNPs) were synthesized using D-fructose as the reducing agent and characterized by high-resolution transmission electron microscopy (HRTEM), energy dispersive X-ray spectroscopy (EDX), powder X-ray diffraction analysis (XRD), inductively coupled plasma optical emission spectrometry (ICP OES), dynamic light scattering (DLS) to obtain zeta potential values and cyclic voltammetry (CV). Particularly, a-SeNPs presented high toxicity toward the resistant cancer cell line MES-SA/Dx5 and its parental MES-SA line. However, they are not toxic against P4 fibroblast cells in comparative studies. (author)

Seasonal variability of iodine and selenium in surface and groundwater as a factor that may contribute to iodine isotope balance in the thyroid gland and its irradiation in case of radioiodine contamination during accidents at the NPP

Science.gov (United States)

Korobova, Elena; Kolmykova, Lyudmila; Ryzhenko, Boris; Berezkin, Viktor; Saraeva, Anastasia

2016-04-01

Radioiodine release to the environment during the accident at the Chernobyl NPP led to the increased risk of the thyroid cancer cases within the contaminated areas, the effect being aggravated in conditions of stable iodine and selenium deficiency in local food chains. Although the drinking water iodine is usually believed to contribute not more than 10% to local diet, our estimations accounting of water content in other products and several regional studies (e.g. India and Australia) proved its portion to be at least twice as much. As radioiodine isotopes are short-lived, their absorption depends greatly on stable iodine and selenium sufficiency in thyroid gland in the first few days of contamination and seasonal variation of stable iodine and selenium in local sources of drinking water may be significant as modifying the resulting thyroid irradiation in different seasons of the year. The main goal of the study was to evaluate seasonal variation of levels of iodine and selenium in natural waters of the Bryansk region as a possible factor affecting the radioiodine intake by thyroid gland of animals and humans in case of radioiodine contamination during the accident. Seasonal I and Se concentration was measured in the years of 2014 and 2015 at 14 test points characterizing surface (river and lake) and drinking groundwater. Obtained data proved considerable seasonal variation of I and Se concentration in natural waters (3,7-8,1 μg/l and 0,04-0,4 μg/l respectively) related to physico-chemical water parameters, such as pH, Eh and fluctuations in concentration of dissolved organic matter. The widest I and Se seasonal variability was observed in surface and well waters, maximum I level being found in autumn at the end of vegetation period characterized by active I leaching from the decomposed organic residues by long lasting precipitations. The content of selenium in the surface waters during summer-autumn (0,06-0,3 μg/l) was higher than in spring (0,04-0,05 �

Sensitivity and toxic mode of action of dietary organic and inorganic selenium in Atlantic salmon (Salmo salar).

Science.gov (United States)

Berntssen, M H G; Sundal, T K; Olsvik, P A; Amlund, H; Rasinger, J D; Sele, V; Hamre, K; Hillestad, M; Buttle, L; Ørnsrud, R

2017-11-01

Depending on its chemical form, selenium (Se) is a trace element with a narrow range between requirement and toxicity for most vertebrates. Traditional endpoints of Se toxicity include reduced growth, feed intake, and oxidative stress, while more recent finding describe disturbance in fatty acid synthesis as underlying toxic mechanism. To investigate overall metabolic mode of toxic action, with emphasis on lipid metabolism, a wide scope metabolomics pathway profiling was performed on Atlantic salmon (Salmo salar) (572±7g) that were fed organic and inorganic Se fortified diets. Atlantic salmon were fed a low natural background organic Se diet (0.35mg Se kg -1 , wet weight (WW)) fortified with inorganic sodium selenite or organic selenomethionine-yeast (SeMet-yeast) at two levels (∼1-2 or 15mgkg -1 , WW), in triplicate for 3 months. Apparent adverse effects were assessed by growth, feed intake, oxidative stress as production of thiobarbituric acid-reactive substances (TBARS) and levels of tocopherols, as well as an overall metabolomic pathway assessment. Fish fed 15mgkg -1 selenite, but not 15mgkg -1 SeMet-yeast, showed reduced feed intake, reduced growth, increased liver TBARS and reduced liver tocopherol. Main metabolic pathways significantly affected by 15mgkg -1 selenite, and to a lesser extent 15mgkg -1 SeMet-yeast, were lipid catabolism, endocannabinoids synthesis, and oxidant/glutathione metabolism. Disturbance in lipid metabolism was reflected by depressed levels of free fatty acids, monoacylglycerols and diacylglycerols as well as endocannabinoids. Specific for selenite was the significant reduction of metabolites in the S-Adenosylmethionine (SAM) pathway, indicating a use of methyl donors that could be allied with excess Se excretion. Dietary Se levels to respectively 1.1 and 2.1mgkg -1 selenite and SeMet-yeast did not affect any of the above mentioned parameters. Apparent toxic mechanisms at higher Se levels (15mgkg -1 ) included oxidative stress and

Selenium and selenium species in feeds and muscle tissue of Atlantic salmon

DEFF Research Database (Denmark)

Sele, Veronika; Ørnsrud, Robin; Sloth, Jens Jørgen

2018-01-01

Selenium (Se) is an essential element for animals, including fish. Due to changes in feed composition for Atlantic salmon (Salmo salar), it may be necessary to supplement feeds with Se. In the present work, the transfer of Se and Se species from feed to muscle of Atlantic salmon fed Se supplemented...... diets was studied. Salmon were fed basal fish feed (0.35 mg Se/kg and 0.89 mg Se/kg feed), or feed supplemented either with selenised yeast or sodium selenite, at low (1–2 mg Se/kg feed) and high (15 mg Se/kg feed) levels, for 12 weeks. For the extraction of Se species from fish muscle, enzymatic...... cleavage with protease type XIV was applied. The extraction methods for Se species from fish feed were optimised, and two separate extraction procedures were applied, 1) enzymatic cleavage for organic Se supplemented feeds and 2) weak alkaline solvent for inorganic Se supplemented feeds, respectively...

No-carrier-added labeling of the neuroprotective Ebselen with selenium-73 and selenium-75.

Science.gov (United States)

Helfer, Andreas; Ermert, Johannes; Humpert, Sven; Coenen, Heinz H

2015-03-01

Selenium-73 is a positron emitting non-standard radionuclide, which is suitable for positron emission tomography. A copper-catalyzed reaction allowed no-carrier-added labeling of the anti-inflammatory seleno-organic compound Ebselen with (73) Se and (75) Se under addition of sulfur carrier in a one-step reaction. The new authentically labeled radioselenium molecule is thus available for preclinical evaluation and positron emission tomography studies. Copyright © 2015 John Wiley & Sons, Ltd.

Relationship between glutation peroxidase (GSH-PX) activity and the uptake of 75-Se by erytrocytes for practical assesment of selenium status in dairy cows

International Nuclear Information System (INIS)

Danius, J.

1988-01-01

An experiment to study the relationship between glutation peroxidase (GSH-Px) activity and the uptake of 75-Se by erytrocytes was conducted for practical assesment of selenium status in Holstein-Friesian (HF) dairy cows. The blood used in the experiment was stored in refrigerator for 7 and 10 days. Radioselenium with a specific activity at about 0.84 mCi/m was used. A high negative correlatin (r = -0.86 and r = -0.98) was found between red blood cell GSH-Px activity and red blood cell uptake of 75-Se. Results indicated that red blood cell uptake of 75-Se can be used for determination of Se status in dairy cattle, although some factors which might affect red blood cell uptake of 75-Se should be calculated first. (author). 21 refs, 2 figs

Absorption, distribution, metabolism and excretion of selenium following oral administration of elemental selenium nanoparticles or selenite in rats

DEFF Research Database (Denmark)

Löschner, Katrin; Hadrup, Niels; Hansen, Marianne

2014-01-01

A suspension of nanoparticles of BSA-stabilized red amorphous elemental selenium (Se) or an aqueous solution of sodium selenite was repeatedly administered by oral gavage for 28 days at 0.05 mg/kg bw/day (low dose) or at 0.5 mg/kg bw/day (high dose) as Se to female rats. Prior to administration...

Temporal measurements and kinetics of selenium release during coal combustion and gasification in a fluidized bed

International Nuclear Information System (INIS)

Shen, Fenghua; Liu, Jing; Zhang, Zhen; Yang, Yingju

2016-01-01

Highlights: • The temporal release of Se from coal combustion and gasification was measured. • Kinetic laws for Se release from coal combustion and gasification were determined. • The influences of temperature and chemical composition of flue gas were clarified. • The interactions of Se species with mineral affect the release kinetics of Se. - Abstract: The temporal release of selenium from coal during combustion and gasification in a fluidized bed was measured in situ by an on-line analysis system of trace elements in flue gas. The on-line analysis system is based on an inductively coupled plasma optical emission spectroscopy (ICP-OES), and can measure concentrations of trace elements in flue gas quantitatively and continuously. The results of on-line analysis suggest that the concentration of selenium in flue gas during coal gasification is higher than that during coal combustion. Based on the results of on-line analysis, a second-order kinetic law r(x) = 0.94e −26.58/RT (−0.56 x 2 −0.51 x + 1.05) was determined for selenium release during coal combustion, and r(x) = 11.96e −45.03/RT (−0.53 x 2 −0.56 x + 1.09) for selenium release during coal gasification. These two kinetic laws can predict respectively the temporal release of selenium during coal combustion and gasification with an acceptable accuracy. Thermodynamic calculations were conducted to predict selenium species during coal combustion and gasification. The speciation of selenium in flue gas during coal combustion differs from that during coal gasification, indicating that selenium volatilization is different. The gaseous selenium species can react with CaO during coal combustion, but it is not likely to interact with mineral during coal gasification.

Highly luminescent CdSe/ZnSe core-shell quantum dots of one-pot preparation in octadecene

NARCIS (Netherlands)

Zeng, Q.; Kong, X.; Zhang, Y.; Zhang, H.

2008-01-01

CdSe/ZnSe core-shell quantum dots were synthesized using a new one-pot procedure where the core was prepared in octadecene. A ZnSe shell around a CdSe nanoparticle was formed by the reaction of selenium-richness on the surfaces of CdSe nanoparticles with Zn2+ from the injected zinc stearate

{sup 77} Se NMR of deuteride vinyl and acetylene selenides; RMn de {sup 77} Se de selenetos vinilicos e acetilenicos deuterados

Energy Technology Data Exchange (ETDEWEB)

Roque, L C; Stefani, H A; Arruda Campos, I.P. de; Comasseto, J V [Sao Paulo Univ., SP (Brazil). Inst. de Quimica

1992-12-31

The main objective of this work is a contribution for establishing a data base sufficient for interpretation of the selenium organic compound spectra. Due to the short literature on acetylene and vinyl selenides, the investigation of these compounds using {sup 77} Se NMR has been considered interesting. Particularly, compounds containing the selenium phenyl group have been selected, as they are larger used in organic chemistry. Non usual deuterated compounds have been applied, viewing simplification of the experimental results interpretation, since the use of deuterium virtually eliminates the Se-H coupling constants, due to the protons of the selenium phenyl group 5 refs., 2 tabs.

Combined effect of selenium and ascorbic acid on alcohol induced hyperlipidemia in male guinea pigs.

Science.gov (United States)

Asha, G S; Indira, M

2004-02-01

Alcoholics usually suffer from malnutrition and are especially deficient in micronutrients like vitamin C, selenium and Zn. In the present study, combined effects of selenium and ascorbic acid on alcohol-induced hyperlipidemia were studied in guinea pigs. Four groups of male guinea pigs were maintained for 45 days as follows: control (1 mg ascorbate (AA)/100 g body mass/day), ethanol (900 mg ethanol/100 g body mass + 1 mg AA/100 g body mass/day), selenium+ascorbic acid [(25 mg AA + 0.05 mg Se)/100 g body mass/day], ethanol+selenium+ascorbic acid [(25 mg AA + 0.05 mg Se + 900 mg ethanol)/100 g body mass/day]. Co-administration of selenium and ascorbic acid along with alcohol reduced the concentration of all lipids, as also evidenced from the decreased activities of hydroxymethylglutaryl-CoA reductase and enhanced activities of plasma lecithin cholesterol acyl transferase and lipoprotein lipase. Concentrations of bile acids were increased. We conclude that the supplementation of Se and ascorbic acid reduced alcohol induced hyperlipidemia, by decreased synthesis and increased catabolism.

Selenium status and cancer mortality in subjects residing in four Canadian provinces

International Nuclear Information System (INIS)

Morris, J.S.; Horsman, T.L.; Spate, V.L.; Baskett, C.K.; Mason, M.M.; Nichols, T.A.; Rohan, T.; Soskolne, C.L.; Jain, M.

2001-01-01

Selenium status in male and female Canadian subjects was measured relative to cancer mortality in their respective provinces. Toenail specimens from 755 subjects, 377 males and 378 females, living in Vancouver (186), Edmonton (188), Toronto (197) and Montreal (184) were analyzed by instrumental neutron activation analysis giving means of 0.968 ± 0.177, 0.950 ± 0.148, 0.932 ± 0.135 and 0.896 ± 0.127 ppm Se, respectively. The effect of selenium determinants such as gender, selenium supplementation and smoking on selenium status is presented. Details of the observed inverse relationship of selenium status and cancer mortality are discussed. (author)

Selenium and vitamin E concentrations in human milk and formula milk from Hungary

International Nuclear Information System (INIS)

Sziklai-Laszlo, I.; Majchrzak, D.; Elmadfa, I.; Cser, M.A.

2009-01-01

The metabolic roles of vitamin E and selenium are closely related, and to a very great extent, each can compensate for the deficiency of the other. The aim of the study was to determine and compare the Se and vitamin E (α- and γ-tocopherol) contents of breast milk and commercially available infant formulas in Hungary. The Se content was measured by instrumental neutron activation analysis (INAA), while the α-, and γ-tocopherol concentrations were determined by high performance liquid chromatography (HPLC). The mean Se concentration was 17.4±2.8 μg/L in transitional and 13.8±2.3 μg/L in mature milk. It was found that, all of the starter (ST), the follow-on (FO) and the specialized formulas (SF) had lower Se content than breast milk. Transitional breast milk resulted in a higher Se intake (14 μg/day) than mature milk (11 μg/day). The daily Se intakes in Hungarian infants were within the Recommended Dietary Allowance (RDA) range. The natural vitamin E contents of human milk were similar during the early and late lactation. Mature breast milk had 3.30±1.13 mg/L α-TE concentration and this was significantly higher than that of in ST (1.98±1.57), and FO (1.77±0.78), or in SF ready to feed preparations (1.03±0.74). The present study suggests that the formulas for the optimal development of young infants, should contain concentrations of these antioxidants on a level which is comparable to that of the human milk. (author)

Selenium and the regulation of cell cycle and apoptosis

Science.gov (United States)

Selenium was discovered by Berzelius in 1817, and the essentiality of Se was demonstrated that trace amounts of Se protected against liver necrosis in vitamin E deficient rats in the mid-1950s. The benefits of Se are many including protection against cancer, heart diseases, muscle disorders, immunit...

Current mass spectrometry strategies for selenium speciation in dietary sources of high-selenium

Energy Technology Data Exchange (ETDEWEB)

Infante, Heidi Goenaga; Hearn, Ruth; Catterick, Tim [LGC Limited, Teddington, Middlesex (United Kingdom)

2005-06-01

This document reviews the most relevant mass spectrometry approaches to selenium (Se) speciation in high-Se food supplements in terms of qualitative and quantitative Se speciation and Se-containing species identification, with special reference to high-Se yeast, garlic, onions and Brazil nuts. Important topics such as complexity of Se speciation in these materials and the importance of combining Se-specific detection and molecule-specific determination of the particular species of this element in parallel with chromatography, to understand their nutritional role and cancer preventive properties are critically discussed throughout. The versatility and potential of mass spectrometric detection in this field are clearly demonstrated. Although great advances have been achieved, further developments are required, especially if ''speciated''certified reference materials (CRMs) are to be produced for validation of measurements of target Se-containing species in Se-food supplements. (orig.)

Selenium inhibits the phytotoxicity of mercury in garlic (Allium sativum)

International Nuclear Information System (INIS)

Zhao, Jiating; Gao, Yuxi; Li, Yu-Feng; Hu, Yi; Peng, Xiaomin; Dong, Yuanxing; Li, Bai; Chen, Chunying; Chai, Zhifang

2013-01-01

To investigate the influence of selenium on mercury phytotoxicity, the levels of selenium and mercury were analyzed with inductively coupled plasma-mass spectrometry (ICP-MS) in garlic tissues upon exposure to different dosages of inorganic mercury (Hg 2+ ) and selenite (SeO 3 2− ) or selenate (SeO 4 2− ). The distributions of selenium and mercury were examined with micro-synchrotron radiation X-ray fluorescence (μ-SRXRF), and the mercury speciation was investigated with micro-X-ray absorption near edge structure (μ-XANES). The results show that Se at higher exposure levels (>1 mg/L of SeO 3 2− or SeO 4 2− ) would significantly inhibit the absorption and transportation of Hg when Hg 2+ levels are higher than 1 mg/L in culture media. SeO 3 2− and SeO 4 2− were found to be equally effective in reducing Hg accumulation in garlic. The inhibition of Hg uptake by Se correlates well with the influence of Se on Hg phytotoxicity as indicated by the growth inhibition factor. Elemental imaging using μ-SRXRF also shows that Se could inhibit the accumulation and translocation of Hg in garlic. μ-XANES analysis shows that Hg is mainly present in the forms of Hg–S bonding as Hg(GSH) 2 and Hg(Met) 2 . Se exposure elicited decrease of Hg–S bonding in the form of Hg(GSH) 2 , together with Se-mediated alteration of Hg absorption, transportation and accumulation, may account for attenuated Hg phytotoxicity by Se in garlic. -- Highlights: ► Hg phytotoxicity can be mitigated by Se supplement in garlic growth. ► Se can inhibit the accumulation and transportation of Hg in garlic tissues. ► Localization and speciation of Hg in garlic can be modified by Se

Cathodic electrodeposition of amorphous elemental selenium from an air- and water-stable ionic liquid.

Science.gov (United States)

Redman, Daniel W; Murugesan, Sankaran; Stevenson, Keith J

2014-01-14

Electrodeposition of selenium from 1-propyl-1-methylpiperidinium bis(trifluoromethylsulfonyl)imide is reported. In situ UV-vis spectroelectrochemistry was used to investigate the reduction of diethyl selenite to form elemental selenium thin films from an ionic liquid-acetonitrile medium. Three reduction peaks of diethyl selenite were observed via cyclic voltammetry and are attributed to the stepwise reduction of the selenium precursor adsorbed on the electrode. The electrodeposition mechanism is influenced by both potential and time. Electrodeposition at -1.7 V vs Pt QRE resulted in the deposition of elemental selenium nanoparticles that with time coalesced to form a continuous film. At reduction potentials more negative than -1.7 V the morphology of the deposit changed significantly due to the reduction of elemental Se to Se(2-). In addition, p-type photoconductivity of the films was observed during the spectroelectrochemical measurements. X-ray diffraction and Raman spectroscopy confirmed that the deposited selenium films were amorphous. X-ray photoelectron spectroscopy and energy dispersive X-ray spectroscopy confirm the films consisted of pure selenium with minor residual contamination from the precursor and ionic liquid.

Derivation of site-specific selenium criteria for a Kentucky stream receiving fly ash effluent

International Nuclear Information System (INIS)

Reash, R.J.; Van Hassel, J.H.

1993-01-01

Blaine Creek, a fifth-order tributary to the Big Sandy River in eastern Kentucky, receives fly ash effluent from Kentucky Power Company's Big Sandy Plant fly ash pond near the creek's mouth. Long-term biosurvey/physicochemical data and speciation studies were used to derive proposed site-specific selenium water quality criteria. Biosurvey results from 1982--1990 were consistent in showing no adverse effects of fly ash discharge, even during low flow conditions when the effluent comprised 75% of creek flow. Five macroinvertebrate parameters (taxa richness, total abundance, EPT taxa, number caddisflies and chironomids) were significantly correlated with % effluent, indicating enhanced communities at high instream waste concentrations. Several fish metrics similarly showed greater enhancement at high % effluent conditions. Selenium speciation studies indicated that selenite (Se 4+ ) represented 100% of total selenium in the effluent. Total selenium concentrations were low at fully mixed downstream reaches. US EPA's Recalculation Procedure was used to calculate site-specific selenium criteria based on Se 4+ toxicity data for resident species. These criteria are higher than statewide criteria which are based on selenium, effects at waterbodies having low turnover rates

Effects of organic selenium in broiler feed on the content of selenium and fatty acid profile in lipids of thigh muscle tissue

Directory of Open Access Journals (Sweden)

Zlata Kralik

2013-01-01

Full Text Available The aim of our study was to determine the effects of selenium supplementation to broiler feed on the content of selenium, total fatty acids in lipids and on the oxidative stability of broiler thigh muscle tissue. The experiment involved 40 broilers fattened for 42 days. During the first three weeks, all broilers consumed starter diet containing 22% crude protein. After three weeks, broilers were divided into two groups and fed finisher diets containing 18% crude protein and supplemented with 3% sunflower oil and 3% linseed oil. Group 1 was not administered artificial selenium; Group 2 was supplemented with organic selenium at the amount of 0.5 mg Se/kg of feed. Significantly higher (P P P > 0.05 and increase of linolenic acid and total n-3 polyunsaturated fatty acids (P < 0.05 in thigh muscle tissue of broilers. Since selenium and n-3 polyunsaturated fatty acids are nutricines, our results show that the produced broiler meat may be considered as functional food.

Selenium derivatives of thyroxine and tri-iodothyronine

International Nuclear Information System (INIS)

Cree, G.M.

1980-01-01

Novel selenium derivatives of thyroxine and tri-iodothyronine are described. They preferably contain at least one 75 Se atom. The compounds are useful in dual isotope assays of thyroid function. (U.K.)

Ecological aspects of selenium and tellurium in human and animal health

Energy Technology Data Exchange (ETDEWEB)

Frost, D V; Ingvoldstad, D

1975-01-01

Animal and human studies indicate that selenium inadequacy, in part, underlies various chronic diseases. Epidemiologic evidence suggests that cancer and heart disease are most common where ambient Se availability is low. Plant Se uptake and Se blood levels are inverse to human cancer mortality. As the active group in glutathione peroxidase, Se/sup -2/ inhibits aberrant oxidations which lead to chronic diseases. It binds heavy metals, and with tocopherol maintains tissue integrity. Sulfur dioxide fallout from the atmosphere, resulting from fossil fuel burning, may diminish the nutritional availability of selenium by diminishing plant uptake. Intensive ruminant grazing returns unavailable Se/sup 0/ to soils. Trimethyl selenium ion, as excreted by animals, also appears to be unavailable to plants. Modern fertilization practices and the effect of buildup of sulfates in the soil, due to acid rains, both appear to lessen the availability of Se to plants. SeO/sub 2/ added to the atmosphere from combustion and volcanic activity react with SO/sub 2/ to yield Se/sup 0/. This is presumed to fall out as particles from the air. How traces of Se are otherwise carried in air, explaining its enrichment in some areas, is unknown. The New Zealand experience with Se inadequacy in animals and man may be repeated in other parts of the world. Se inadequacy is far more of a human health problem than Se toxicity. There are no known adverse health effects from tellurium, other than tellurium breath. 164 references, 5 figures, 3 tables.

In{sub 6}Se{sub 7} thin films by heating thermally evaporated indium and chemical bath deposited selenium multilayers

Energy Technology Data Exchange (ETDEWEB)

Ornelas, R.E.; Avellaneda, D. [Universidad Autonoma de Nuevo Leon, Facultad de Ingenieria Mecanica y Electrica, San Nicolas de los Garza, Nuevo Leon-66450 (Mexico); Shaji, S. [Universidad Autonoma de Nuevo Leon, Facultad de Ingenieria Mecanica y Electrica, San Nicolas de los Garza, Nuevo Leon-66450 (Mexico); Universidad Autonoma de Nuevo Leon-CIIDIT, Apodaca, N.L (Mexico); Castillo, G.A.; Roy, T.K. Das [Universidad Autonoma de Nuevo Leon, Facultad de Ingenieria Mecanica y Electrica, San Nicolas de los Garza, Nuevo Leon-66450 (Mexico); Krishnan, B., E-mail: kbindu_k@yahoo.com [Universidad Autonoma de Nuevo Leon, Facultad de Ingenieria Mecanica y Electrica, San Nicolas de los Garza, Nuevo Leon-66450 (Mexico); Universidad Autonoma de Nuevo Leon-CIIDIT, Apodaca, N.L (Mexico)

2012-05-15

Indium selenide (In{sub 6}Se{sub 7}) thin films were prepared via selenization of thermally evaporated indium thin films by dipping in sodium selenosulphate solution followed by annealing in nitrogen atmosphere. First, indium was thermally evaporated on glass substrate. Then, the indium coated glass substrates were dipped in a solution containing 80 ml 0.125 M sodium selenosulphate and 1.5 ml dilute acetic acid (25%) for 5 min. Glass/In-Se layers were annealed at 200-400 Degree-Sign C in nitrogen atmosphere (0.1 Torr) for 30 min. X-ray diffraction studies showed the formation of monoclinic In{sub 6}Se{sub 7}. Morphology of the thin films formed at different conditions was analyzed using Scanning electron microscopy. The elemental analysis was done using Energy dispersive X-ray detection. Electrical conductivity under dark and illumination conditions was evaluated. Optical band gap was computed using transmittance and reflectance spectra. The band gap value was in the range 1.8-2.6 eV corresponding to a direct allowed transition. We studied the effect of indium layer thickness and selenium deposition time on the structure, electrical and optical properties of In{sub 6}Se{sub 7} thin films.

Role of selenium toxicity and oxidative stress in aquatic birds

Science.gov (United States)

Hoffman, D.J.

2002-01-01

Adverse effects of selenium (Se) in wild aquatic birds have been documented as a consequence of pollution of the aquatic environment by subsurface agricultural drainwater and other sources. These effects include mortality, impaired reproduction with teratogenesis, reduced growth, histopathological lesions and alterations in hepatic glutathione metabolism. A review is provided, relating adverse biological effects of Se in aquatic birds to altered glutathione metabolism and oxidative stress. Laboratory studies, mainly with an organic form of Se, selenomethionine, have revealed oxidative stress in different stages of the mallard (Anas platyrhynchos) life cycle. As dietary and tissue concentrations of Se increase, increases in plasma and hepatic GSH peroxidase activities occur, followed by dose-dependent increases in the ratio of hepatic oxidized to reduced glutathione (GSSG:GSH) and ultimately hepatic lipid peroxidation measured as an increase in thiobarbituric acid reactive substances (TBARS). One or more of these oxidative effects were associated with teratogenesis (4.6 ppm wet weight Se in eggs), reduced growth in ducklings (15 ppm Se in liver), diminished immune function (5 ppm Se in liver) and histopathological lesions (29 ppm Se in liver) in adults. Manifestations of Serelated effects on glutathione metabolism were also apparent in field studies in seven species of aquatic birds. Reduced growth and possibly immune function but increased liver:body weight and hepatic GSSG:GSH ratios were apparent in American avocet (Recurvirostra americana) hatchlings from eggs containing 9 ppm Se. In blacknecked stilts (Himantopus mexicanus), which contained somewhat lower Se concentrations, a decrease in hepatic GSH was apparent with few other effects. In adult American coots (Fulica americana), signs of Se toxicosis included emaciation, abnormal feather loss and histopathological lesions. Mean liver concentrations of 28 ppm Se (ww) in the coots were associated with elevated

Photodynamic effect and mechanism study of selenium-enriched phycocyanin from Spirulina platensis against liver tumours.

Science.gov (United States)

Liu, Zijian; Fu, Xiang; Huang, Wei; Li, Chunxia; Wang, Xinyan; Huang, Bei

2018-03-01

Selenium-containing phycocyanin (Se-PC) has been proved to have many biological effects, including anti-inflammatory and antioxidant. In this study, we investigated the photodynamic therapy (PDT) effects of Se-PC against liver tumour in vitro and in vivo experiment. Our results demonstrated that the half lethal dose of Se-PC PDT on HepG2 cells was 100μg/ml PC containing 20% selenium. Se-PC location migration from lysosomes to mitochondria was time dependent. In in vivo experiments, the tumour inhibition rate was 75.4% in the Se-PC PDT group, compared to 52.6% in PC PDT group. Histological observations revealed that the tumour cells outside the tissue showed cellular necrosis, and those inside the tissue exhibited apoptotic nuclei and digested vacuoles in the cytoplasm after Se-PC PDT treatment. Antioxidant enzyme analysis indicated that GSH-Px activity was linked to the selenium content of Se-PC, and SOD activity was affected by PC PDT. Therefore, Se-PC PDT could induce cell death through free radical production of PDT in tumours and enhance the activity of antioxidant enzymes with selenium in vivo. The mechanism of Se-PC PDT against liver tumour involves hematocyte damage and mitochondria-mediated apoptosis accompanied with autophagy inhibition during early stage of tumour development, which displayed new prospect and offered relatively safe way for cancer therapy. Copyright © 2017 Elsevier B.V. All rights reserved.

An application of nitrogen microwave-induced plasma mass spectrometry to isotope dilution analysis of selenium in marine organisms

Energy Technology Data Exchange (ETDEWEB)

Shirasaki, Toshihiro [Hitachi Instruments Engineering Co. Ltd., Hitachinaka, Ibaraki (Japan); Yoshinaga, Jun; Morita, Masatoshi; Okumoto, Toyoharu; Oishi, Konosuke

1996-01-01

Nitrogen microwave-induced plasma mass spectrometry was studied for its applicability to the isotope dilution analysis of selenium in biological samples. Spectroscopic interference by calcium, which is present in high concentrations in biological samples, was investigated. No detectable background spectrum was observed for the major selenium isotopes of {sup 78}Se and {sup 80}Se. No detectable interferences by sodium, potassium, calcium and phosphorus on the isotope ratio {sup 80}Se/{sup 78}Se were observed up to concentration of 200 mg/ml. The method was applied to the analysis of selenium in biological reference materials of marine organisms. The results showed good agreement between the certified and found values. (author).

Selenium status of South Bohemia seniors characterized by INAA of blood serum

International Nuclear Information System (INIS)

Kvicala, J.; Zamrazil, V.; Nemecek, J.; Jiranek, J.

2008-01-01

To estimate the status of selenium in seniors of the South Bohemia region, Czech Republic, 481 serum samples from seniors living in 17 Asylum Houses for seniors in the age between 60 and 99 years were obtained. Samples were analyzed by instrumental neutron activation analysis with concurrent analysis of 4 reference materials for quality assurance. Average concentration of serum Se, arithmetic means in individual Asylum Houses, frequency distribution of serum Se concentrations as well as five years running monitoring of serum Se concentrations of one group of seniors proved selenium deficiency of the elderly population of the region South Bohemia. (author)

Mercury and selenium relationship in a tropical estuarine fish

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Ana Carolina Pizzochero

2015-11-01

Full Text Available Aquatic systems have been considered as final sinks for persistent and bioaccumulative toxicants (PBTs, such as metals and organohalogen compounds. Among the trace elements, non-essential metals deserve special attention due to their toxicity. In this context, mercury (Hg should be highlighted due to its toxic effects, which comprise neurotoxicity, nephrotoxicity, hepatotoxicity, genotoxicity, among others. Several studies have highlighted the selenium-mediated methylmercury detoxification process, via mercury selenide formation in tissues of marine vertebrates. Despite being an essential element, selenium may also be toxic in high concentrations. This study focused on Guanabara Bay (GB, a heavily polluted urban estuary in Rio de Janeiro state (Brazil, where the whitemouth croaker (Micropogonias furnieri provides a valuable fishery resource. Therefore, hepatic (Hg and Se and muscular (Hg concentrations of these elements were determined in GB whitemouth croakers. Mercury and selenium measurements were performed by cold vapor atomic absorption spectrometry (CV-AAS and electrothermal AAS (ET-AAS, respectively. Total mercury (THg concentrations in muscle (n=19 ranged from 184.9 to 858.6 (ng/g, while in liver they varied from 11.05 to 1188 (ng/g. Hepatic selenium concentrations ranged from 7820 to 40085 (ng/g. The hepatic Se:THg molar ratio ranged from 40,8 to 3102,5. The results showed a significant correlation between hepatic mercury and selenium levels, but the molar ratio suggests the absence of mercury selenide formation. Some of the Se concentrations found were above the threshold level for freshwater fish (12000 ng/g; however, it is not yet clear if these concentrations are toxic for marine fish as well. More studies are necessary for evaluating the impact of such exposure in fish from Guanabara Bay.

Selenium fertilization on lentil (Lens culinaris Medikus) grain yield, seed selenium concentration, and antioxidant activity

Science.gov (United States)

Selenium (Se) is an essential element for mammals but has not been considered as an essential element for higher plants. Lentil (Lens culinaris Medik.) is a cool season food legume rich in protein and a range of micronutrients including minerals (iron and zinc), folates, and carotenoids. The objecti...

Stabilization/solidification of selenium-impacted soils using Portland cement and cement kiln dust.

Science.gov (United States)

Moon, Deok Hyun; Grubb, Dennis G; Reilly, Trevor L

2009-09-15

Stabilization/solidification (S/S) processes were utilized to immobilize selenium (Se) as selenite (SeO(3)(2-)) and selenate (SeO(4)(2-)). Artificially contaminated soils were prepared by individually spiking kaolinite, montmorillonite and dredged material (DM; an organic silt) with 1000 mg/kg of each selenium compound. After mellowing for 7 days, the Se-impacted soils were each stabilized with 5, 10 and 15% Type I/II Portland cement (P) and cement kiln dust (C) and then were cured for 7 and 28 days. The toxicity characteristic leaching procedure (TCLP) was used to evaluate the effectiveness of the S/S treatments. At 28 days curing, P doses of 10 and 15% produced five out of six TCLP-Se(IV) concentrations below 10mg/L, whereas only the 15% C in DM had a TCLP-Se(IV) concentration soil-cement slurries aged for 30 days enabled the identification of Se precipitates by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM)-energy dispersive X-ray spectroscopy (EDX). XRD and SEM-EDX analyses of the Se(IV)- and Se(VI)-soil-cement slurries revealed that the key selenium bearing phases for all three soil-cement slurries were calcium selenite hydrate (CaSeO(3).H(2)O) and selenate substituted ettringite (Ca(6)Al(2)(SeO(4))(3)(OH)(12).26H(2)O), respectively.

Relationship between arsenic and selenium in workers occupationally exposed to inorganic arsenic.

Science.gov (United States)

Janasik, Beata; Zawisza, Anna; Malachowska, Beata; Fendler, Wojciech; Stanislawska, Magdalena; Kuras, Renata; Wasowicz, Wojciech

2017-07-01

The interaction between arsenic (As) and selenium (Se) has been one of the most extensively studied. The antagonism between As and Se suggests that low Se status plays an important role in aggravating arsenic toxicity in diseases development. The objective of this study was to assess the Se contents in biological samples of inorganic As exposed workers (n=61) and in non-exposed subjects (n=52). Median (Me) total arsenic concentration in urine of exposed workers was 21.83μg/g creat. (interquartile range (IQR) 15.49-39.77) and was significantly higher than in the control group - (Me 3.75μg/g creat. (IQR 2.52-9.26), piAs+MMA+DMA) was significantly associated with the high total selenium urine excretion (B=0.14 (95%CI (confidence interval) 0.05-0.23)). Combination of both arsenic and selenium status to assess the risk of arsenic-induced diseases requires more studies with regard to both the analysis of speciation, genetics and the influence of factors such as nutritional status. Copyright © 2017 Elsevier GmbH. All rights reserved.

Effect of solvent on Se-modified ruthenium/carbon catalyst for oxygen reduction

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Chuanxiang Zhang

2014-12-01

Full Text Available Se-modified ruthenium supporting on carbon (Sex–Ru/C electrocatalyst was prepared by solvothermal one-step synthesis method. The reaction mechanism was revealed after discussing impact of different solvents (i-propanol and EG in solvotermal reaction. The result showed that the grain size of Se-modified ruthenium electrocatalyst was as small as 1 to 3 nm and highly dispersed on carbon surface. X-ray photoelectron spectroscopy (XPS presented that selenium mainly existed in the catalyst in the form of elemental selenium and selenium oxides when the solvent was EG and i-propanol, respectively. The oxygen reduction reaction (ORR performance was improved by appearance of selenium oxides.

The role of selenium in predicting preeclampsia

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Z Ghaemi

2013-10-01

Full Text Available Introduction: Preeclampsia is a common disorder that is a leading cause of perinatal and maternal morbidity and mortality; however its specific etiology has still remained obscure.The first step in preventing preeclampsia is early detection of women at risk. Since there is no valid and reliable screening test, appropriate diagnostic and screening tests are necessary, which are inexpensive, non-invasive and beneficial for pregnant women. Therefore, regarding the role of selenium as an antioxidant in the prevention preeclampsia, this study was designed which aimed to determine the prognostic value of plasma selenium levels in the diagnosis of preeclampsia in primigravida women Methods: In a nested case control design, a sample of 650 normal primigravida women of 24-28 weeks participated in the study. Subjects who involved the case group were followed up for 3 months and 38 were affected by preeclampsia. Blood samples were obtained from these 38patients as well as from 38 subjects as their matched controls. Moreover, the amount of selenium was measured by atomic absorption spectrometry. Results: The mean level of selenium in blood plasma of the cases was significantly lower than in their matched controls. The present study findings revealed that pregnant women with serum Se < 66.1 μg/L had a significantly increased risk of preeclampsia. Conclusion: Lower plasma selenium level in women destines to suffering from preeclampsia which confirms the destructive effect of selenium deficiency as an antioxidant in etiopathology of preeclampsia. Measurement of plasma selenium can improve the prediction of preeclampsia; thus, it seems that plasma selenium level test owns an acceptable sensitivity and specificity for predicting preeclampsia.

Antioxidant effects of selenium on lung injury in paraquat intoxicated rats

Science.gov (United States)

Kim, K.S.; Suh, G.J.; Kwon, W.Y.; Kwak, Y.H.; Lee, Kenneth; Lee, H.J.; Jeong, K.Y.; Lee, M.W.

2012-01-01

CONTEXT: Paraquat (PQ) causes lethal intoxication by inducing oxidant injury to the lung. Selenium is a cofactor for glutathione peroxidase (GPx), which is one of the major endogenous antioxidant enzymes. OBJECTIVE: To determine whether selenium post-treatment activates GPx, decreases lung injury, and improves survival in PQ intoxicated rats. MATERIALS AND METHODS: Male Spraque-Dawley rats were categorized into three groups: sham (n = 6), PQ (n = 12), and PQ + Se (n = 12). In the PQ and PQ + Se groups, 50 mg/kg of PQ was administered intraperitoneally. After 10 minutes, 60 μg/kg of Se (PQ + Se) or saline (PQ) was administered via the tail vein. Six rats per group were euthanized 6 hours or 24 hours later. Lung tissues were harvested for the measurement of GPx activity, reduced glutathione (GSH), glutathione disulfide (GSSG) and malondialdehyde (MDA) and for histological analysis. Using separated set of rats, survival of PQ (n = 10) and PQ + Se (n = 10) were observed for 72 hours. RESULTS: GPx activity in the PQ group at the 6-hour and 24-hour time points was lower than in the sham group (p CONCLUSION: Single dose of selenium post-treatment activates GPx and attenuates lipid peroxidation and lung injury early after paraquat intoxication, but does not improve 72 hours of survival.

Selenium hyperaccumulation offers protection from cell disruptor herbivores

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Quinn Colin F

2010-08-01

Full Text Available Abstract Background Hyperaccumulation, the rare capacity of certain plant species to accumulate toxic trace elements to levels several orders of magnitude higher than other species growing on the same site, is thought to be an elemental defense mechanism against herbivores and pathogens. Previous research has shown that selenium (Se hyperaccumulation protects plants from a variety of herbivores and pathogens. Selenium hyperaccumulating plants sequester Se in discrete locations in the leaf periphery, making them potentially more susceptible to some herbivore feeding modes than others. In this study we investigate the protective function of Se in the Se hyperaccumulators Stanleya pinnata and Astragalus bisulcatus against two cell disrupting herbivores, the western flower thrips (Frankliniella occidentalis and the two-spotted spider mite (Tetranychus urticae. Results Astragalus bisulcatus and S. pinnata with high Se concentrations (greater than 650 mg Se kg-1 were less subject to thrips herbivory than plants with low Se levels (less than 150 mg Se kg-1. Furthermore, in plants containing elevated Se levels, leaves with higher concentrations of Se suffered less herbivory than leaves with less Se. Spider mites also preferred to feed on low-Se A. bisulcatus and S. pinnata plants rather than high-Se plants. Spider mite populations on A. bisulcatus decreased after plants were given a higher concentration of Se. Interestingly, spider mites could colonize A. bisulcatus plants containing up to 200 mg Se kg-1 dry weight, concentrations which are toxic to many other herbivores. Selenium distribution and speciation studies using micro-focused X-ray fluorescence (μXRF mapping and Se K-edge X-ray absorption spectroscopy revealed that the spider mites accumulated primarily methylselenocysteine, the relatively non-toxic form of Se that is also the predominant form of Se in hyperaccumulators. Conclusions This is the first reported study investigating the

Assessing the anticancer compounds Se-methylselenocysteine and glucosinolates in Se-biofortified broccoli (brassica oleracea L. var. italica) sprouts and florets

Science.gov (United States)

Broccoli (Brassica oleracea L. var. italica) is a rich source of chemopreventive compounds. Here, we evaluated and compared the effect of selenium (Se) treatment on the accumulation of anticancer compound Se-methylselenocysteine (SeMSCys) and glucosinolates in broccoli sprouts and florets. Total Se ...

Nanocrystalline hydroxyapatite doped with selenium oxyanions: a new material for potential biomedical applications.

Science.gov (United States)

Kolmas, Joanna; Oledzka, Ewa; Sobczak, Marcin; Nałęcz-Jawecki, Grzegorz

2014-06-01

Selenium-substituted hydroxyapatites containing selenate SeO4(2-) or selenite SeO3(2-) ions were synthesized using a wet precipitation method. The selenium content was determined by atomic absorbance spectrometry. The raw, unsintered powders were also characterized using powder X-ray diffraction, middle-range FT-IR spectroscopy and transmission electron microscopy with energy-dispersive X-ray spectroscopic microanalysis. The synthesized apatites were found to be pure and nanocrystalline with a crystal size similar to that in bone mineral. The incorporation of selenium oxyanions into the crystal lattice was confirmed. The toxicity of hydroxyapatites containing selenite or selenate ions was evaluated with a protozoan assay and bacterial luminescence test. Copyright © 2014 Elsevier B.V. All rights reserved.

Effect of salinity on Brassica rapa var. toria (BRSRT under selenium defence: A trial to assess the protective role of selenium

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Akanksha SAO

2017-12-01

Full Text Available The present study assesses the role of selenium, an antioxidant in salt-stressed plants. A hydroponic trial of sodium selenate (Na2SeO4 on the growth, oxidative stress and antioxidant protection system of Brassica rapa var. toria (BRSRT plant was studied. 40 µmol and 100 µmol of Na2SeO4 were hydroponically applied to BRSRT roots with 50 mmol and 100 mmol sodium chloride (NaCl for 12 days. Plant growth, biomass production and photosynthetic pigments at 100 mmol salt stress was inhibited while oxidative stress indicators, for example, hydrogen peroxide and lipid peroxidation were stimulated. Supplementation of 40 µmol Na2SeO4 with 50 mmol and 100 mmol NaCl improved growth, photosynthetic pigments and acted as an antioxidant by inhibiting lipid peroxidation and increasing superoxide dismutase, ascorbate peroxidase, catalase, glutathione peroxidase, glutathione reductase activities. The in-gel assays also showed enhanced activities of these enzymes. At 100 µmol concentration, selenium under salt stress, repressed growth and expression of antioxidant enzymes and stimulated oxidative stress with enhanced glutathione peroxidase activity. Under consolidated stress treatment, an addition of 40 µmol Na2SeO4 was the most effective for both NaCl concentrations. The finding reveals that the optimal selenium supplementation presents a promising potential for use in conditions of relatively high levels of NaCl stress for BRSRT seedlings.

Internal correction of spectral interferences and mass bias for selenium metabolism studies using enriched stable isotopes in combination with multiple linear regression.

Science.gov (United States)

Lunøe, Kristoffer; Martínez-Sierra, Justo Giner; Gammelgaard, Bente; Alonso, J Ignacio García

2012-03-01

The analytical methodology for the in vivo study of selenium metabolism using two enriched selenium isotopes has been modified, allowing for the internal correction of spectral interferences and mass bias both for total selenium and speciation analysis. The method is based on the combination of an already described dual-isotope procedure with a new data treatment strategy based on multiple linear regression. A metabolic enriched isotope ((77)Se) is given orally to the test subject and a second isotope ((74)Se) is employed for quantification. In our approach, all possible polyatomic interferences occurring in the measurement of the isotope composition of selenium by collision cell quadrupole ICP-MS are taken into account and their relative contribution calculated by multiple linear regression after minimisation of the residuals. As a result, all spectral interferences and mass bias are corrected internally allowing the fast and independent quantification of natural abundance selenium ((nat)Se) and enriched (77)Se. In this sense, the calculation of the tracer/tracee ratio in each sample is straightforward. The method has been applied to study the time-related tissue incorporation of (77)Se in male Wistar rats while maintaining the (nat)Se steady-state conditions. Additionally, metabolically relevant information such as selenoprotein synthesis and selenium elimination in urine could be studied using the proposed methodology. In this case, serum proteins were separated by affinity chromatography while reverse phase was employed for urine metabolites. In both cases, (74)Se was used as a post-column isotope dilution spike. The application of multiple linear regression to the whole chromatogram allowed us to calculate the contribution of bromine hydride, selenium hydride, argon polyatomics and mass bias on the observed selenium isotope patterns. By minimising the square sum of residuals for the whole chromatogram, internal correction of spectral interferences and mass

Response of selenium changes in blood using cyclic activation analysis

International Nuclear Information System (INIS)

Spyrou, N.M.; Akanle, O.B.; Damyanova, A.A.

1986-01-01

A study was undertaken to investigate the response of selenium uptake and washout in whole blood and its components in healthy subjects, aged 20 to 30 yr, who were given selenium as a supplement to their usual diet, in the form of a yeast tablet (200 mg) containing 100 μg of the element together with vitamins A, C, and E (natural). Selenium has gained worldwide interest not only as an essential trace element but as a potent modifier of environmental hazards and as a naturally occurring toxicant. It is important therefore to investigate the character and the degree of the changes in healthy people on selenium supplementation. Cyclic activation analysis was used for the determination of selenium concentration through the detection of /sup 77m/Se (17.5 s), because of the increased sensitivity of the method and the large number of samples involved

Targeted sulphur and selenium speciation in yeast by parallel elemental and molecular mass spectrometry

DEFF Research Database (Denmark)

Hillestrøm, Peter René; Mapelli, Valeria; Olsson, Lisbeth

Selenium supplement, often selenized yeast, are currently the subject of intense study owing to their potential preventive effects against cancer. However, fundamental knowledge of the yeast’s metabolism is required for metabolic engineering biosynthetic production of potent Se-species. A method ...... determination of metabolites present. Selenium metabolites were detected by simultaneous ICP-MS and ESI-MS/MS while targeted sulphur species were determined by ESI-MS/MS.......Selenium supplement, often selenized yeast, are currently the subject of intense study owing to their potential preventive effects against cancer. However, fundamental knowledge of the yeast’s metabolism is required for metabolic engineering biosynthetic production of potent Se-species. A method...

Selenium behaviour in the presence of minerals and under hydrogen atmosphere

International Nuclear Information System (INIS)

Jeanson, A.; Gebala, N.; Fattahi, M.; Landesman, C.; Granbow, B.

2010-01-01

Document available in extended abstract form only. In the framework of nuclear waste handling, radionuclide diffusion ability in soil has to be studied in order to better evaluate the risks of infiltration of radioactive elements in our environment. Indeed, radionuclide behaviour is deeply dependent of the soil characteristics, like its composition, pH, potentials, or the water composition. In the case of a deep geological depository, the high-level radioactive waste will be put in a glass matrix, confined in a steel container. Those containers are exposed to corrosion phenomena, forming ferrous minerals, hydrogen gas, and potentially leading to radionuclide leaks. In this case, radionuclides could be in the presence of minerals and hydrogen in a reducing environment. 79 Selenium is expected to be present as a fission product of 235 U. It is present at the oxidation state (+IV) in the glass matrix, but under reductive conditions ([-400;-300] mV (E.N.H.)) can be under the form of selenide (Se(-II)). Those reductive condition could exist in Callovo-Oxfordian soil (COX) in the presence of H 2 gas and Fe(II) coming from the containers corrosion. Thus, our study focuses on Se(IV) and Se(-II) behaviour in the presence of minerals (magnetite, and COX argillite), under hydrogen atmosphere. According to Martinez et al., selenium is sorbed on magnetite surface. When pH increases, selenium is less adsorbed on magnetite. Se(IV) sorption mechanism has been proposed by Mayant et al.: it implies the formation of two types of complexes in the inner sphere of magnetite surface. Moreover, Sheinost et al. show that synthetic nanoparticles of magnetite quantitatively reduce Se(IV) to Se(-II) in a few hours, leading to the formation of an iron selenide cluster close to Fe II 5 Fe III 2 Se 8 . While Se(IV) sorption on minerals has been broadly studied, very few data is found about Se(-II), due to its very high sensibility to oxidation causing its handling to be difficult. Suspensions of

Plasma and breast-milk selenium in HIV-infected Malawian mothers are positively associated with infant selenium status but are not associated with maternal supplementation: results of the Breastfeeding, Antiretrovirals, and Nutrition study.

Science.gov (United States)

Flax, Valerie L; Bentley, Margaret E; Combs, Gerald F; Chasela, Charles S; Kayira, Dumbani; Tegha, Gerald; Kamwendo, Debbie; Daza, Eric J; Fokar, Ali; Kourtis, Athena P; Jamieson, Denise J; van der Horst, Charles M; Adair, Linda S

2014-04-01

Selenium is found in soils and is essential for human antioxidant defense and immune function. In Malawi, low soil selenium and dietary intakes coupled with low plasma selenium concentrations in HIV infection could have negative consequences for the health of HIV-infected mothers and their exclusively breastfed infants. We tested the effects of lipid-based nutrient supplements (LNS) that contained 1.3 times the Recommended Dietary Allowance of sodium selenite and antiretroviral drugs (ARV) on maternal plasma and breast-milk selenium concentrations. HIV-infected Malawian mothers in the Breastfeeding, Antiretrovirals, and Nutrition study were randomly assigned at delivery to receive: LNS, ARV, LNS and ARV, or a control. In a subsample of 526 mothers and their uninfected infants, we measured plasma and breast-milk selenium concentrations at 2 or 6 (depending on the availability of infant samples) and 24 wk postpartum. Overall, mean (± SD) maternal (range: 81.2 ± 20.4 to 86.2 ± 19.9 μg/L) and infant (55.6 ± 16.3 to 61.0 ± 15.4 μg/L) plasma selenium concentrations increased, whereas breast-milk selenium concentrations declined (14.3 ± 11.5 to 9.8 ± 7.3 μg/L) from 2 or 6 to 24 wk postpartum (all P milk selenium from 2 or 6 to 24 wk postpartum (both P milk selenium, but maternal selenium concentrations were positively associated with infant plasma selenium at 2 or 6 and 24 wk postpartum (P milk selenium concentrations. Future research should examine effects of more readily incorporated forms of selenium (ie, selenomethionine) in HIV-infected breastfeeding women.

Comparison of the redox chemistry of sulfur- and selenium-containing analogs of uracil✰

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Payne, N. Connor; Geissler, Andrew; Button, Aileen; Sasuclark, Alexandru R.; Schroll, Alayne L.; Ruggles, Erik L.; Gladyshev, Vadim N.; Hondal, Robert J.

2017-01-01

Selenium is present in proteins in the form of selenocysteine, where this amino acid serves catalytic oxidoreductase functions. The use of selenocysteine in nature is strongly associated with redox catalysis. However, selenium is also found in a 2-selenouridine moiety at the wobble position of tRNAGlu, tRNAGln and tRNALys. It is thought that the modifications of the wobble position of the tRNA improves the selectivity of the codon-anticodon pair as a result of the physico-chemical changes that result from substitution of sulfur and selenium for oxygen. Both selenocysteine and 2-selenouridine have widespread analogs, cysteine and thiouridine, where sulfur is used instead. To examine the role of selenium in 2-selenouridine, we comparatively analyzed the oxidation reactions of sulfur-containing 2-thiouracil-5-carboxylic acid (s2c5Ura) and its selenium analog 2-selenouracil-5-carboxylic acid (se2c5Ura) using 1H-NMR spectroscopy, 77Se-NMR spectroscopy, and liquid chromatography-mass spectrometry. Treatment of s2c5Ura with hydrogen peroxide led to oxidized intermediates, followed by irreversible desulfurization to form uracil-5-carboxylic acid (c5Ura). In contrast, se2c5Ura oxidation resulted in a diselenide intermediate, followed by conversion to the seleninic acid, both of which could be readily reduced by ascorbate and glutathione. Glutathione and ascorbate only minimally prevented desulfurization of s2c5Ura, whereas very little deselenization of se2c5Ura occurred in the presence of the same antioxidants. In addition, se2c5Ura but not s2c5Ura showed glutathione peroxidase activity, further suggesting that oxidation of se2c5Ura is readily reversible, while oxidation of s2c5Ura is not. The results of the study of these model nucleobases suggest that the use of 2-selenouridine is related to resistance to oxidative inactivation that otherwise characterizes 2-thiouridine. As the use of selenocysteine in proteins also confers resistance to oxidation, our findings suggest a

Comparison of the redox chemistry of sulfur- and selenium-containing analogs of uracil.

Science.gov (United States)

Payne, N Connor; Geissler, Andrew; Button, Aileen; Sasuclark, Alexandru R; Schroll, Alayne L; Ruggles, Erik L; Gladyshev, Vadim N; Hondal, Robert J

2017-03-01

Selenium is present in proteins in the form of selenocysteine, where this amino acid serves catalytic oxidoreductase functions. The use of selenocysteine in nature is strongly associated with redox catalysis. However, selenium is also found in a 2-selenouridine moiety at the wobble position of tRNA Glu , tRNA Gln and tRNA Lys . It is thought that the modifications of the wobble position of the tRNA improves the selectivity of the codon-anticodon pair as a result of the physico-chemical changes that result from substitution of sulfur and selenium for oxygen. Both selenocysteine and 2-selenouridine have widespread analogs, cysteine and thiouridine, where sulfur is used instead. To examine the role of selenium in 2-selenouridine, we comparatively analyzed the oxidation reactions of sulfur-containing 2-thiouracil-5-carboxylic acid (s 2 c 5 Ura) and its selenium analog 2-selenouracil-5-carboxylic acid (se 2 c 5 Ura) using 1 H-NMR spectroscopy, 77 Se-NMR spectroscopy, and liquid chromatography-mass spectrometry. Treatment of s 2 c 5 Ura with hydrogen peroxide led to oxidized intermediates, followed by irreversible desulfurization to form uracil-5-carboxylic acid (c 5 Ura). In contrast, se 2 c 5 Ura oxidation resulted in a diselenide intermediate, followed by conversion to the seleninic acid, both of which could be readily reduced by ascorbate and glutathione. Glutathione and ascorbate only minimally prevented desulfurization of s 2 c 5 Ura, whereas very little deselenization of se 2 c 5 Ura occurred in the presence of the same antioxidants. In addition, se 2 c 5 Ura but not s 2 c 5 Ura showed glutathione peroxidase activity, further suggesting that oxidation of se 2 c 5 Ura is readily reversible, while oxidation of s 2 c 5 Ura is not. The results of the study of these model nucleobases suggest that the use of 2-selenouridine is related to resistance to oxidative inactivation that otherwise characterizes 2-thiouridine. As the use of selenocysteine in proteins also confers

Selenium for preventing cancer

Science.gov (United States)

Vinceti, Marco; Dennert, Gabriele; Crespi, Catherine M; Zwahlen, Marcel; Brinkman, Maree; Zeegers, Maurice PA; Horneber, Markus; D'Amico, Roberto; Del Giovane, Cinzia

2015-01-01

.69, 95% confidence interval (CI) 0.53 to 0.91, N = 8) and cancer mortality (OR 0.60, 95% CI 0.39 to 0.93, N = 6) associated with higher selenium exposure. Gender-specific subgroup analysis provided no clear evidence of different effects in men and women (P value 0.47), although cancer incidence was lower in men (OR 0.66, 95% CI 0.42 to 1.05, N = 6) than in women (OR 0.90, 95% CI 0.45 to 1.77, N = 2). The most pronounced decreases in risk of site-specific cancers were seen for stomach, bladder and prostate cancers. However, these findings have limitations due to study design, quality and heterogeneity that complicate interpretation of the summary statistics. Some studies suggested that genetic factors may modify the relation between selenium and cancer risk-a hypothesis that deserves further investigation. In RCTs, we found no clear evidence that selenium supplementation reduced the risk of any cancer (risk ratio (RR) 0.90, 95% CI 0.70 to 1.17, two studies, N = 4765) or cancer-related mortality (RR 0.81, 95% CI 0.49 to 1.32, two studies, N = 18,698), and this finding was confirmed when the analysis was restricted to studies with low risk of bias. The effect on prostate cancer was imprecise (RR 0.90, 95% CI 0.71 to 1.14, four studies, N = 19,110), and when the analysis was limited to trials with low risk of bias, the interventions showed no effect (RR 1.02, 95% CI 0.90 to 1.14, three studies, N = 18,183). The risk of non-melanoma skin cancer was increased (RR 1.44, 95% CI 0.95 to 1.17, three studies, N = 1900). Results of two trials-the Nutritional Prevention of Cancer Trial (NPCT) and the Selenium and Vitamin E Cancer Trial (SELECT)-also raised concerns about possible increased risk of type 2 diabetes, alopecia and dermatitis due to selenium supplements. An early hypothesis generated by NPCT that individuals with the lowest blood selenium levels at baseline could reduce their risk of cancer, particularly of prostate cancer, by increasing selenium intake has not been

Immobilization of selenium by biofilm of Shewanella putrefaciens with and without Fe(III)-citrate complex

International Nuclear Information System (INIS)

Suzuki, Yoshinori; Sakama, Yosuke; Saiki, Hiroshi; Kitamura, Akira; Yoshikawa, Hideki; Tanaka, Kazuya

2014-01-01

To investigate the effect of biofilms on selenium migration, we examined selenite reduction by biofilms of an iron-reducing bacterium, Shewanella putrefaciens, under anaerobic conditions. The biofilms were grown under static conditions on culture cover glasses coated with poly-L-lysine. Optical microscopic observation of the biofilms after staining with 0.1% crystal violet solution revealed that the cells were surrounded by filamentous extracellular polymer substances. Exposure of the biofilms to aqueous selenite resulted in the formation of red precipitates, which were assigned to nanoparticulate elemental selenium using X-ray absorption near-edge structure analysis. Micrographic observation showed that the precipitates immobilized at the biofilms. We also examined the selenite reduction in the presence of Fe(III)-citrate complex. In this case, a dark brown precipitate formed at the biofilms. X-ray absorption near-edge structure analysis revealed that the precipitate was a mixed compound with elemental selenium and iron selenide. These findings indicate that biofilms of iron-reducing bacteria in the environment can immobilize selenium by reducing Se(IV) to Se(0), and Fe(III)-citrate complex promotes the reduction of Se(0) to Se(-II). (author)

Selenium transformation in coal mine spoils: Its environmental impact assessment. Final report

Energy Technology Data Exchange (ETDEWEB)

Harness, J.; Atalay, A.; Koll, K.J.; Zhang, H.; Maggon, D.

1991-12-31

The objective of this program was to conduct an environmental impact assessment study for selenium from coal mine spoils. The use of in-situ lysimetry to predict selenium speciation, transformation, and mobility under natural conditions was evaluated. The scope of the study was to construct and test field-scale lysimeter and laboratory mini-column to assess mobility and speciation of selenium in coal mine overburden and soil systems; to conduct soil and groundwater sampling throughout the state of Oklahoma for an overall environmental impact assessment of selenium; and to conduct an in-depth literature review on the solubility, speciation, mobility, and toxicity of selenium from various sources. Groundwater and surface soil samples were also collected from each county in Oklahoma. Data collected from the lysimeter study indicated that selenium in the overburden of the abandoned mine site was mainly found in the selenite form. The amount of selenite found was too low and immobile to be of concern to the environment. The spoil had equilibrated long enough (over 50 years) that most of the soluble forms of selenium have already been lost. Examination of the overburden indicated the presence of pyrite crystals that precipitated over time. The laboratory mini-column study indicated that selenite is quite immobile and remained on the overburden material even after leaching with dilute acid. Data from groundwater samples indicated that based on the current permissible level for selenium in groundwater (0.01 mg Se/L), Oklahoma groundwater is widely contaminated with the element. However, according to the new regulation (0.05 mg Se/L), which is to be promulgated in 1992, only 9 of the 77 counties in the state exceed the limit.

Catalytic oxidant scavenging by selenium-containing compounds

DEFF Research Database (Denmark)

Carroll, Luke; Pattison, David I; Fu, Shanlin

2017-01-01

Myeloperoxidase produces strong oxidants during the immune response to destroy invading pathogens. However, these oxidants can also cause tissue damage, which contributes to the development of numerous inflammatory diseases. Selenium containing compounds, including selenomethionine (SeMet) and 1,...

Selenium inhibits the phytotoxicity of mercury in garlic (Allium sativum)

Energy Technology Data Exchange (ETDEWEB)

Zhao, Jiating [CAS Key Laboratory of Nuclear Analytical Techniques, Key Lab for Biomedical Effects of Nanomaterial and Nanosafety, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China); Gao, Yuxi, E-mail: gaoyx@ihep.ac.cn [CAS Key Laboratory of Nuclear Analytical Techniques, Key Lab for Biomedical Effects of Nanomaterial and Nanosafety, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China); Li, Yu-Feng; Hu, Yi; Peng, Xiaomin [CAS Key Laboratory of Nuclear Analytical Techniques, Key Lab for Biomedical Effects of Nanomaterial and Nanosafety, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China); Dong, Yuanxing [Department of Physics, Xinzhou Teachers University, Xinzhou 034000 (China); Li, Bai; Chen, Chunying [CAS Key Laboratory of Nuclear Analytical Techniques, Key Lab for Biomedical Effects of Nanomaterial and Nanosafety, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China); Chai, Zhifang, E-mail: chaizf@ihep.ac.cn [CAS Key Laboratory of Nuclear Analytical Techniques, Key Lab for Biomedical Effects of Nanomaterial and Nanosafety, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China)

2013-08-15

To investigate the influence of selenium on mercury phytotoxicity, the levels of selenium and mercury were analyzed with inductively coupled plasma-mass spectrometry (ICP-MS) in garlic tissues upon exposure to different dosages of inorganic mercury (Hg{sup 2+}) and selenite (SeO{sub 3}{sup 2−}) or selenate (SeO{sub 4}{sup 2−}). The distributions of selenium and mercury were examined with micro-synchrotron radiation X-ray fluorescence (μ-SRXRF), and the mercury speciation was investigated with micro-X-ray absorption near edge structure (μ-XANES). The results show that Se at higher exposure levels (>1 mg/L of SeO{sub 3}{sup 2−} or SeO{sub 4}{sup 2−}) would significantly inhibit the absorption and transportation of Hg when Hg{sup 2+} levels are higher than 1 mg/L in culture media. SeO{sub 3}{sup 2−} and SeO{sub 4}{sup 2−} were found to be equally effective in reducing Hg accumulation in garlic. The inhibition of Hg uptake by Se correlates well with the influence of Se on Hg phytotoxicity as indicated by the growth inhibition factor. Elemental imaging using μ-SRXRF also shows that Se could inhibit the accumulation and translocation of Hg in garlic. μ-XANES analysis shows that Hg is mainly present in the forms of Hg–S bonding as Hg(GSH){sub 2} and Hg(Met){sub 2}. Se exposure elicited decrease of Hg–S bonding in the form of Hg(GSH){sub 2}, together with Se-mediated alteration of Hg absorption, transportation and accumulation, may account for attenuated Hg phytotoxicity by Se in garlic. -- Highlights: ► Hg phytotoxicity can be mitigated by Se supplement in garlic growth. ► Se can inhibit the accumulation and transportation of Hg in garlic tissues. ► Localization and speciation of Hg in garlic can be modified by Se.

Selenium Derivatization of Nucleic Acids for Phase and Structure Determination in Nucleic Acid X-ray Crystallography

Directory of Open Access Journals (Sweden)

Zhen Huang

2008-03-01

Full Text Available Selenium derivatization (via selenomethionine of proteins for crystal structure determination via MAD phasing has revolutionized protein X-ray crystallography. It is estimated that over two thirds of all new crystal structures of proteins have been determined via Se-Met derivatization. Similarly, selenium functionalities have also been successfully incorporated into nucleic acids to facilitate their structure studies and it has been proved that this Se-derivatization has advantages over halogen strategy, which was usually used as a traditional method in this field. This review reports the development of site-specific selenium derivatization of nucleic acids for phase determination since the year of 2001 (mainly focus on the 2’-position of the ribose. All the synthesis of 2’-SeMe modified phosphoramidite building blocks (U, C, T, A, G and the according oligonucleotides are included. In addition, several structures of selenium contained nucleic acid are also described in this paper.

Optimised selenium enrichment of Artemia sp. feed to improve red drum (Sciaenops ocellatus) larvae rearing.

Science.gov (United States)

Juhász, Péter; Lengyel, Szvetlana; Udvari, Zsolt; Sándor, Alex Nagy; Stündl, László

2017-09-01

Selenium is an essential microelement for the normal functioning of life processes. Moreover, it is a component of enzymes with antioxidant effects. However, it has the smallest window of any micronutrient between requirement and toxicity. Selenium is a regularly used element in fish feeds; moreover, enriching zooplankton with selenium to rear larvae is also a well-known technology. It is accepted that the most common starter foods of fish larvae, natural rotifers contain the smallest dosage of selenium, but providing selenium enriched Artemia sp. instead could increase survival and growth rate of fish. However, no such references are available for the red drum (Sciaenops ocellatus) larvae. Therefore, in this study, Artemia sp. was enriched with nano-selenium of verified low toxicity and easy availability in 5 treatments (1, 5, 10, 50, 100 mg/l Se), and then, fish larvae were fed with four of these enriched Artemia stocks (1, 5, 10, 50 mg/l Se) and a control group. At the end of the 9-day-long experiment, survival rate (S) and growth parameters (SL, W, K-factor, SGR) of fish larvae were calculated as well as their selenium retention and glutathione peroxidase enzyme activity were analysed. It was revealed that a moderate level of selenium enrichment (~4 mg/kg dry matter) of Artemia sp. positively influences the rearing efficiency (i.e. survival and growth) of fish larvae, but higher dosages of selenium could cause adverse effects.

Selenium for the Prevention of Cutaneous Melanoma

Science.gov (United States)

Cassidy, Pamela B.; Fain, Heidi D.; Cassidy, James P.; Tran, Sally M.; Moos, Philip J.; Boucher, Kenneth M.; Gerads, Russell; Florell, Scott R.; Grossman, Douglas; Leachman, Sancy A.

2013-01-01

The role of selenium (Se) supplementation in cancer prevention is controversial; effects often depend on the nutritional status of the subject and on the chemical form in which Se is provided. We used a combination of in vitro and in vivo models to study two unique therapeutic windows for intervention in the process of cutaneous melanomagenisis, and to examine the utility of two different chemical forms of Se for prevention and treatment of melanoma. We studied the effects of Se in vitro on UV-induced oxidative stress in melanocytes, and on apoptosis and cell cycle progression in melanoma cells. In vivo, we used the HGF transgenic mouse model of UV-induced melanoma to demonstrate that topical treatment with l-selenomethionine results in a significant delay in the time required for UV-induced melanoma development, but also increases the rate of growth of those tumors once they appear. In a second mouse model, we found that oral administration of high dose methylseleninic acid significantly decreases the size of human melanoma xenografts. Our findings suggest that modestly elevation of selenium levels in the skin might risk acceleration of growth of incipient tumors. Additionally, certain Se compounds administered at very high doses could have utility for the treatment of fully-malignant tumors or prevention of recurrence. PMID:23470450

Toenail mercury and dyslipidemia: Interaction with selenium.

Science.gov (United States)

Park, Kyong; Seo, Eunmin

2017-01-01

confirmed the beneficial effects of selenium against the harmful effects of mercury in humans with relatively high consumption of fish. Our finding has important implications in making dietary recommendations regarding optimal levels of fish and selenium intakes. Further studies are warranted to determine the appropriate level of fish consumption, considering both methylmercury and selenium exposure, in a larger prospective cohort or RCT. Copyright © 2016 Elsevier GmbH. All rights reserved.

Biofortification and phytoremediation of selenium in China

Science.gov (United States)

Biofortification is an agricultural process that increases the uptake and accumulation of specific nutrients, e.g. selenium (Se), in agricultural food products through plant breeding, genetic engineering, and manipulation of agronomic practices. The development and uses of biofortified agricultural ...

Polarographic determination of selenium in indium

International Nuclear Information System (INIS)

Kaplan, B.Ya.; Mikheeva, V.A.; Priz, N.B.

1978-01-01

The procedure of determining nx10 -6 % Se in indium after concentrating in an elemental form on arsenic and sulphur has been developed. The selenium content is determined by inversion a.c. polarography on a sulphuric-acid background in the presence of Cu(2), potassium bichromate, and sodium pyrophosphate. 5.7x10 -6 % Se in metal indium has been determined by this procedure, the mean standard deviation being Sr=0.26

Assessment of selenium mineralization and availability from catch crops

DEFF Research Database (Denmark)

Stavridou, Eleftheria; Thorup-Kristensen, Kristian; Young, S.D.

2011-01-01

Selenium (Se) release from four plant species (Indian mustard, fodder radish, Italian ryegrass and hairy vetch) was measured under controlled leaching conditions and in a pot incubation experiment as part of a study of the potential for using these plant species as Se catch crops. Catch crops may...

Selenium deficiency occurs in some patients with moderate-to-severe cirrhosis and can be corrected by administration of selenate but not selenomethionine: a randomized controlled trial123

Science.gov (United States)

Burk, Raymond F; Hill, Kristina E; Motley, Amy K; Byrne, Daniel W; Norsworthy, Brooke K

2015-01-01

Background: Selenomethionine, which is the principal dietary form of selenium, is metabolized by the liver to selenide, which is the form of the element required for the synthesis of selenoproteins. The liver synthesizes selenium-rich selenoprotein P (SEPP1) and secretes it into the plasma to supply extrahepatic tissues with selenium. Objectives: We conducted a randomized controlled trial to determine whether cirrhosis is associated with functional selenium deficiency (the lack of selenium for the process of selenoprotein synthesis even though selenium intake is not limited) and, if it is, whether the deficiency is associated with impairment of selenomethionine metabolism. Design: Patients with Child-Pugh (C-P) classes A, B, and C (mild, moderate, and severe, respectively) cirrhosis were supplemented with a placebo or supranutritional amounts of selenium as selenate (200 or 400 μg/d) or as selenomethionine (200 μg/d) for 4 wk. Plasma SEPP1 concentration and glutathione peroxidase (GPX) activity, the latter due largely to the selenoprotein GPX3 secreted by the kidneys, were measured before and after supplementation. Results: GPX activity was increased more by both doses of selenate than by the placebo in C-P class B patients. The activity was not increased more by selenomethionine supplementation than by the placebo in C-P class B patients. Plasma selenium was increased more by 400 μg Se as selenate than by the placebo in C-P class C patients. Within the groups who responded to selenate, there was a considerable variation in responses. Conclusion: These results indicate that severe cirrhosis causes mild functional selenium deficiency in some patients that is associated with impaired metabolism of selenomethionine. This trial was registered at clinicaltrials.gov as NCT00271245. PMID:26468123

Distribution and retention of inhaled selenium compounds in the rat

International Nuclear Information System (INIS)

Burkstaller, M.A.; Cuddihy, R.G.

1978-01-01

Selenium containing compounds released into the atmosphere during coal combustion are principally of the elemental form or the dioxide. These compounds differ greatly in their chemical properties. Fischer-344 rats were exposed via inhalation to both the dioxide and the red elemental form of selenium. Subsequently, measurements were made of internal absorption, organ distribution and retention, and modes of excretion. A radiotracer, 75 Se, was incorporated into the aerosol to facilitate these measurements. Retention of both aerosols in the total body showed long term components with half lives of 43 and 15 days accounting for 25 to 35% of the initially deposited selenium. Excretion occurred principally by way of urine. For both aerosols, selenium absorbed into the systemic circulation was mainly found in the liver, kidney, blood, gastrointestinal tract and bone

Effect of selenium-vitamin E injection in ewes on reproduction and ...

African Journals Online (AJOL)

user

selenium (Se) and Se plus vitamin E on oestrus, fertility, prolificacy, number of lambs ... deficiency plays a role in numerous economically important livestock diseases, ... Fecundity rate = number of lambs born/number of ewes lambing x 100.

Dietary supply of selenium for adolescents in three residential care orphanages in Southern Ghana

International Nuclear Information System (INIS)

Adotey, Dennis K.; Stibilj, Vekoslava; Serfor-Armah, Yaw; Nyarko, Benjamin J.B.; Jaćimović, Radojko

2011-01-01

Adolescents require optimum dietary supply of the essential trace mineral selenium (Se); however the absence of reliable and accurate data on the dietary supply of selenium for the adolescent population in Ghanaian residential care orphanages have made it difficult for public health nutritionists to assess the adequacy of the dietary supply. The dietary supply of selenium for adolescents (12–15 years) in three residential care orphanages, (Osu, Tutu-Akwapim and Teshie), in Southern Ghana have been evaluated by sampling their 24-h duplicate diets (including water) for 7-consecutive days using the duplicate diet sampling technique. The mass fraction of selenium in the blended lyophilized homogenates of duplicate diets was determined by radiochemical neutron activation analysis (RNAA). The validity of the RNAA method for selenium determination was checked by analyses of NIST SRM 1548a (Typical diet). The chemical yield of the radiochemical separation was determined by spectrophotometry. The average mass fractions of selenium in the blended lyophilized 24-hour duplicate diets for Osu, Tutu-Akwapim and Teshie were; 165 ± 61 [117.2–285.2], 203 ± 68 [110.5–304.9] and 250 ± 92 [128.8–408.0] ng Se g −1 lyophilized matter respectively. The average dietary supply of Se were, 57.6 ± 17.3 [42.2–88.4], 82.0 ± 30.7 [44.3–136.2] and 91.7 ± 44.2 [46.0–153.4] μg Se day −1 for Osu, Tutu-Akwapim and Teshie orphanages respectively. The data generated will help public health nutritionists in the provision of dietary advice and nutritional support for the studied orphanages, as well as other orphanages. The data will also help in the planning of institutional diets.

Influence of relative trophic position and carbon source on selenium bioaccumulation in turtles from a coal fly-ash spill site

International Nuclear Information System (INIS)

Van Dyke, James U.; Hopkins, William A.; Jackson, Brian P.

2013-01-01

Selenium (Se) is a bioaccumulative constituent of coal fly-ash that can disrupt reproduction of oviparous wildlife. In food webs, the greatest enrichment of Se occurs at the lowest trophic levels, making it readily bioavailable to higher consumers. However, subsequent enrichment at higher trophic levels is less pronounced, leading to mixed tendencies for Se to biomagnify. We used stable isotopes ( 15 N and 13 C) in claws to infer relative trophic positions and relative carbon sources, respectively, of seven turtle species near the site of a recently-remediated coal fly-ash spill. We then tested whether Se concentrations differed with relative trophic position or relative carbon source. We did not observe a strong relationship between δ 15 N and Se concentration. Instead, selenium concentrations decreased with increasing δ 13 C among species. Therefore, in an assemblage of closely-related aquatic vertebrates, relative carbon source was a better predictor of Se bioaccumulation than was relative trophic position. -- Highlights: •Stable isotope results showed trophic separation among turtle species. •Selenium concentrations did not biomagnify with relative trophic position. •Selenium concentrations decreased with increasing δ 13 C among species. •Carbon source influenced Se bioaccumulation in an assemblage of related vertebrates. -- Stable isotope differences indicate that claw selenium concentrations differ among relative carbon sources, and not among relative trophic positions, in an assemblage of aquatic turtles

Quality control in the neutron activation analysis of biological markers for selenium in epidemiological investigations

International Nuclear Information System (INIS)

Morris, J.S.; Ngwenyama, R.A.; Guthrie, J.M.; Brockman, J.D.; Spate, V.L.; Robertson, J.D.

2008-01-01

Instrumental neutron activation analysis is routinely used at the MURR to quantify selenium in prospectively-collected biologic markers including blood serum and toenails. These specimens are typically collected from well-defined cohort populations participating in investigations assessing selenium intake and incidence of chronic disease endpoints. These epidemiological investigations, whether observational (case-control) or clinical (intervention), typically generate thousands of samples. The purpose of this paper is to assess, through evaluation of quality control results, if the achievable accuracy and precision in the measurement of selenium using NAA is adequate to determine a relative risk of 1.2 at high confidence in epidemiological studies. (author)

Chapter 6: Selenium Toxicity to Aquatic Organisms

Science.gov (United States)

This chapter addresses the characteristics and nature of organic selenium (Se) toxicity to aquatic organisms, based on the most current state of scientific knowledge. As such, the information contained in this chapter relates to the 'toxicity assessment' phase of aquatic ecologi...

Methods of Selenium Supplementation: Bioavailability and Determination of Selenium Compounds.

Science.gov (United States)

Bodnar, Malgorzata; Szczyglowska, Marzena; Konieczka, Piotr; Namiesnik, Jacek

2016-01-01

Selenium, a "dual-surface" element, maintains a very thin line between a level of necessity and harmfulness. Because of this, a deficiency or excess of this element in an organism is dangerous and causes health-related problems, both physically and mentally. The main source of selenium is a balanced diet, with a proper selection of meat and plant products. Meanwhile, the proper assimilation of selenium into these products depends on their bioavailability, bioaccessibility, and/or bioactivity of a given selenium compound. From the time when it was discovered that selenium and its compounds have a significant influence on metabolic processes and in many countries throughout the world, a low quantity of selenium was found in different parts of the environment, pressure was put upon an effective and fast method of supplementing the environment with the help of selenium. This work describes supplementation methods applied with the use of selenium, as well as new ideas for increasing the level of this element in various organisms. Based on the fact that selenium appears in the environment at trace levels, the determination of total amount of selenium or selenium speciation in a given sample demands the selection of appropriate measurement methods. These methods are most often comprised of a sample preparation technique and/or a separation technique as well as a detection system. The work presents information on the subject of analytical methods used for determining selenium and its compounds as well as examples in literature of their application.

Effect of nano-sized, elemental selenium supplement on the proteome of chicken liver.

Science.gov (United States)

Gulyas, G; Csosz, E; Prokisch, J; Javor, A; Mezes, M; Erdelyi, M; Balogh, K; Janaky, T; Szabo, Z; Simon, A; Czegledi, L

2017-06-01

The nano-sized (100-500 nm) selenium has higher bioavailability and relatively lower toxicity compared to other selenium forms. The objective of the present study was to compare liver proteome profiles of broiler chicken fed with control diet without Se supplementation and diet supplemented with nano-Se with 4.25 mg/kg DM. Differential proteome analyses were performed by two-dimensional gel electrophoresis (2D-PAGE) followed by tryptic digestion and protein identification by liquid chromatography-mass spectrometry (LC-MS). Seven hundred and eight spots were detected, and 18 protein spots showed significant difference in their intensity (p selenium supplementation induced a dietary stress. Selenium supplementation may influence the metabolism of fatty acids and carbohydrates and antioxidant system, and increase the quantity of cytoskeletal actin and the expression of actin regulatory protein as well. Journal of Animal Physiology and Animal Nutrition © 2016 Blackwell Verlag GmbH.

The Determination of Selenium in Blood. RCN Report

International Nuclear Information System (INIS)

Japenga, J.; Das, H.A.; Hoede, D.; Zonderhuis, J.

1971-12-01

A procedure for the determination of selenium by neutron activation analysis in blood is given. The radionuclide used is 75 Se (T½ = 120 d). Chemical separation is performed by precipitation of the element. (author)

Effect of chronic selenium exposure on the freshwater bivalve Corbicula fluminea

Energy Technology Data Exchange (ETDEWEB)

Fournier, E.; Adam, C.; Massabuau, J.C.; Garnier-Laplace, J. [CEA Cadarache (DEI/SECRE/LRE), Laboratory of Radioecology and Ecotoxicology, Institute for Radioprotection and Nuclear Safety, 13 - Saint-Paul-lez-Durance (France)

2004-07-01

Selenium is essential for most of living organisms. In oxic to moderately oxic fresh-waters, Se exists predominantly in the (+VI) and (+IV) oxidation states as selenate (SeO{sub 4}{sup 2-}) and selenite (SeO{sub 3}{sup 2-}) respectively, whereas in the biota it is incorporated as Se(-II) into seleno-proteins or amino-acids, or as elemental selenium Se(0). At low concentrations, it acts against oxidative damages mainly as the glutathione peroxidase seleno-dependant, but it may be toxic at higher levels (for example, by replacing sulphur in important biomolecules). In filter feeders, such as the freshwater bivalve Corbicula fluminea, selected as biological model, the ventilation activity is a primary limiting step that controls the water influx and therefore the delivery of contaminants. Consequently, a series of short-term experiments were performed to study the effects of different dissolved Se concentrations and forms (selenite; selenate; selenomethionine) on the ventilation activity of Corbicula fluminea and Se tissular distribution. The modification of the ventilation activity of the Se-exposed groups, in comparison to this of reference groups (not exposed to Se) varied greatly according to the form and the concentrations of the Se used. Se concentrations in tissues indicated that selenite was the less bioavailable form whereas selenomethionine displayed the opposite trend. On the basis of this set of experiments, a limited number of conditions have been selected to provide highly contrasting ventilation flow rates and selenium bioaccumulation levels, in order to study the effects of long term exposures, i) at the molecular level, by measuring bio-markers of oxidative stress (forms of glutathione, glutathione peroxidase, glutathione reductase, superoxide dismutase, catalase, and bio-marker of genotoxicity (comet assay), ii) at the (sub)cellular level by analysing Se micro-localisation in target organs and iii) at the individual level by monitoring the variation

The Voltammetric Analysis of Selenium Electrodeposition from H2SeO3 Solution on Gold Electrode

OpenAIRE

Kowalik R.

2015-01-01

The different voltammetry techniques were applied to understand the process of selenium deposition from sulfate solution on gold polycrystalline electrode. By applying the cycling voltammetry with different scan limits as well as the chronoamper-ometry combined with the cathodic and anodic linear stripping voltammetry, the different stages of the deposition of selenium were revealed. It was found that the process of reduction of selenous acid on gold surface exhibits a multistage character. T...

Beneficial Effects of Selenium on Some Morphological and Physiological Trait of Hot Pepper (Capsicum anuum

Directory of Open Access Journals (Sweden)

L. Shekari

2016-07-01

Full Text Available Introduction: Aluminum (Al, cobalt (Co, sodium (Na, selenium (Se, and silicon (Si are considered as beneficial elements for plants. They are not required for all plants but they can improve the growth and development of some plant species. Selenium is an essential element for human with antioxidant and antivirus functions but is not considered essential for higher plants. Selenium is reported to be protective against cancer and more than 40 types of diseases are associated with Se deficiency. The amounts of selenium in food also depend on the amount of the element in the soil. However, its beneficial role in improving plant growth and stress tolerances is well established. Plants revealed different physiological reactions into the Se levels, some specious accumulate it unlike some which are sensitive and Se is a toxic element for them. Some studies showed that Se can reduce adverse effects of salinity, drought, high and low temperatures and also heavy metal stress by enhancing antioxidant defense and MG detoxification systems. Pepper is one of the most important vegetable crops which have strong antioxidant properties. The effect of Se on vegetable especially on hot pepper is not well documented. Materials and Methods: Present experiment was designed in order to study the effects of different concentrations of selenium on vegetative growth and physiological trait of hot pepper (Capsicum annum cv. kenya in hydroponic conditions in the greenhouse at the Department of Horticulture Science, Islamic Azad University of Shiraz (Iran under natural light with a day/night average temperature of 25/17 °C, relative humidity of 50±8.5% and photoperiod 14/10 (day/night. This experiment was carried out based on completed randomized design (CRD with 5 Se levels at (0 as control, 3, 5, 7 and 10 µM with 3 replications. 30 days old seedling with uniform size were selected and transplanted into 4 L pot containing a mixture of peat moss and perlite (1:1. The

Review: Selenium contamination, fate, and reactive transport in groundwater in relation to human health

Science.gov (United States)

Bailey, Ryan T.

2017-06-01

Selenium (Se) is an essential micro-nutrient for humans, but can be toxic at high levels of intake. Se deficiency and Se toxicity are linked with serious diseases, with some regions worldwide experiencing Se deficiency due to Se-poor rocks and soils and other areas dealing with Se toxicity due to the presence of Se-enriched geologic materials. In addition, Se is consumed primarily through plants that take up Se from soil and through animal products that consume these plants. Hence, the soil and groundwater system play important roles in determining the effect of Se on human health. This paper reviews current understanding of Se fate and transport in soil and groundwater systems and its relation to human health, with a focus on alluvial systems, soil systems, and the interface between alluvial systems and Cretaceous shale that release Se via oxidation processes. The review focuses first on the relation between Se and human health, followed by a summary of Se distribution in soil-aquifer systems, with an emphasis on the quantitative relationship between Se content in soil and Se concentration in underlying groundwater. The physical, chemical, and microbial processes that govern Se fate and transport in subsurface systems then are presented, followed by numerical modeling techniques used to simulate these processes in study regions and available remediation strategies for either Se-deficient or Se-toxic regions. This paper can serve as a guide to any field, laboratory or modeling study aimed at assessing Se fate and transport in groundwater systems and its relation to human health.

Selenium regulates gene expression of selenoprotein W in chicken skeletal muscle system.

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Ruan, Hongfeng; Zhang, Ziwei; Wu, Qiong; Yao, Haidong; Li, Jinlong; Li, Shu; Xu, Shiwen

2012-01-01

Selenoprotein W (SelW) is abundantly expressed in skeletal muscles of mammals and necessary for the metabolism of skeletal muscles. However, its expression pattern in skeletal muscle system of birds is still uncovered. Herein, to investigate the distribution of SelW mRNA in chicken skeletal muscle system and its response to different selenium (Se) status, 1-day-old chickens were exposed to various concentrations of Se as sodium selenite in the feed for 35 days. In addition, myoblasts were treated with different concentrations of Se in the medium for 72 h. Then the levels of SelW mRNA in skeletal muscles (wing muscle, pectoral muscle, thigh muscle) and myoblasts were determined on days 1, 15, 25, and 35 and at 0, 24, 48, and 72 h, respectively. The results showed that SelW was detected in all these muscle components and it increased both along with the growth of organism and the differentiation process of myoblasts. The thigh muscle is more responsive to Se intake than the other two skeletal muscle tissues while the optimal Se supplementation for SelW mRNA expression in chicken myoblasts was 10(-7) M. In summary, Se plays important roles in the development of chicken skeletal muscles. To effect optimal SelW gene expression, Se must be provided in the diet and the media in adequate amounts and neither at excessive nor deficient levels.

Solubility constraints affecting the migration of selenium through the cementitious backfill of a geological disposal facility

Energy Technology Data Exchange (ETDEWEB)

Felipe-Sotelo, M., E-mail: m.felipe-sotelo@lboro.ac.uk; Hinchliff, J.; Evans, N.D.M.; Read, D.

2016-03-15

Highlights: • The availability of Ca controls the concentration of SeO{sub 3}{sup 2−} in solution. • Cellulose degradation products increase the solubility of SeO{sub 3}{sup 2−} at alkaline pH. • Selenite diffuses faster through the backfill NRVB than through fly ash cements. - Abstract: This work presents the study of the solubility of selenium under cementitious conditions and its diffusion, as SeO{sub 3}{sup 2−}, through monolithic cement samples. The solubility studies were carried out under alkaline conditions similar to those anticipated in the near-field of a cement-based repository for low- and intermediate-level radioactive waste. Experiments were conducted in NaOH solution, 95%-saturated Ca(OH){sub 2}, water equilibrated with a potential backfill material (Nirex reference vault backfill, NRVB) and in solutions containing cellulose degradation products, with and without reducing agents. The highest selenium concentrations were found in NaOH solution. In the calcium-containing solutions, analysis of the precipitates suggests that the solubility controlling phase is Ca{sub 2}SeO{sub 3}(OH){sub 2}·2H{sub 2}O, which appears as euhedral rhombic crystals. The presence of cellulose degradation products caused an increase in selenium concentration, possibly due to competitive complexation, thereby, limiting the amount of calcium available for precipitation. Iron coupons had a minor effect on selenium solubility in contrast to Na{sub 2}S{sub 2}O{sub 4}, suggesting that effective reduction of Se(IV) occurs only at E{sub h} values below −300 mV. Radial through-diffusion experiments on NRVB and in a fly ash cement showed no evidence of selenium breakthrough after one year. However, autoradiography of the exposed surfaces indicated that some migration had occurred and that selenium was more mobile in the higher porosity backfill than in the fly ash cement.

[Effect of selenium on the uptake and translocation of manganese, iron, phosphorus and selenium in rice (Oryza sativa L.)].

Science.gov (United States)

Hu, Ying; Huang, Yi-Zong; Huang, Yan-Chao; Liu, Yun-Xia; Liang, Jian-Hong

2013-10-01

A pot experiment was conducted to clarify the effect of selenium on the uptake and translocation of manganese (Mn), iron (Fe) , phosphorus (P) and selenium (Se) in rice ( Oryza sativa L.). The results showed that addition of Se led to the significant increase of Se concentration in iron plaque on the root surface, root, shoot, husk and brown rice, and significant decrease of Mn concentration in shoot, husk and brown rice. At the Se concentrations of 0.5 and 1.0 mg.kg-1 in soil, Mn concentrations in rice shoot decreased by 32. 2% and 35.0% respectively, in husk 22.0% and 42.6% , in brown rice 27.5% and 28.5% , compared with the Se-free treatment. There was no significant effect of Se on the P and Fe concentrations in every parts of rice, except for Fe concentrations in husk. The translocation of P and Fe from iron plaque, root, shoot and husk to brown rice was not significantly affected by Se addition, but Mn translocation from iron plaque and root to brown rice was significantly inhibited by Se addition. Addition of 1.0 mg.kg-1. Se resulted in the decrease of translocation factor from iron plaque and root to brown rice by 38.9% and 37.9%, respectively, compared with the control treatment. The distribution ratios of Mn, Fe, P and Se in iron plaque, root, shoot, husk and brown rice were also affected by Se addition. The results indicated that Mn uptake, accumulation and translocation in rice could be decreased by the addition of Se in soil, therefore, Se addition could reduce the Mn harm to human health through food chain.

Vaporization studies on elemental tellurium and selenium by Knudsen effusion mass spectrometry

Energy Technology Data Exchange (ETDEWEB)

Viswanathan, R., E-mail: rvis1953@gmail.com; Balasubramanian, R., E-mail: rbs@igcar.gov.in; Darwin Albert Raj, D., E-mail: darwinalbertraj1953@gmail.com; Sai Baba, M., E-mail: msb@igcar.gov.in; Lakshmi Narasimhan, T.S., E-mail: tslak@igcar.gov.in

2014-08-01

Highlights: • A detailed KEMS study of vaporization of elemental tellurium and selenium systems. • Clusters Te{sub i}(g) (i = 2 to 7) and Se{sub i}(g) (i = 2 to 9) identified over Te(s) and Se(s). • p–T relations for Te{sub i}(g) (590 to 690 K) and Se{sub i}(g) (380 to 480 K). • Vapor phase of Te dominated by Te{sub 2}(g) (∼95%) while that of Se by Se{sub 6}(g) (∼50%) and Se{sub 5}(g) (∼25%). • Sublimation and atomization enthalpies deduced for Te{sub i}(g) and Se{sub i}(g). - Abstract: Vaporization studies on elemental tellurium and selenium were conducted by Knudsen effusion mass spectrometry in the temperature range of 590–690 K and 380–480 K, respectively. The ionic species Te{sub i}{sup +} (i = 1–7) and Se{sub i}{sup +}(g) (i = 1–9) were detected in the mass spectra over these two condensed phases. Measurement of ion intensities were performed as a function of electron impact energy and as a function of temperature (at different electron impact energies) for identifying the gaseous precursor species as well as for determining the partial pressure–temperature relations and sublimation enthalpies for these species. While the major species over elemental tellurium was confirmed to be Te{sub 2}(g) (with all other gaseous species Te{sub 3}–Te{sub 7} put together constituting less than 5%), the major species over elemental selenium was found to be Se{sub 6}(g), closely followed by Se{sub 5}(g) (with other gaseous species Se{sub 2}–Se{sub 4} and Se{sub 7}–Se{sub 9} put together also moderately constituting ∼25%). From the partial pressures, the thermodynamic data for the sublimation reactions i Te(s) = Te{sub i}(g) and i Se(s) = Se{sub i}(g) were deduced by second- and third-law methods. The atomization enthalpies of tellurium and selenium clusters were also deduced by using the recommended enthalpies of formation of monomeric species. Comparison of the findings obtained in the present study with those in previous studies revealed

Antagonistic Growth Effects of Mercury and Selenium in Caenorhabditis elegans Are Chemical-Species-Dependent and Do Not Depend on Internal Hg/Se Ratios.

Science.gov (United States)

Wyatt, Lauren H; Diringer, Sarah E; Rogers, Laura A; Hsu-Kim, Heileen; Pan, William K; Meyer, Joel N

2016-03-15

The relationship between mercury (Hg) and selenium (Se) toxicity is complex, with coexposure reported to reduce, increase, and have no effect on toxicity. Different interactions may be related to chemical compound, but this has not been systematically examined. Our goal was to assess the interactive effects between the two elements on growth in the nematode Caenorhabditis elegans, focusing on inorganic and organic Hg (HgCl2 and MeHgCl) and Se (selenomethionine, sodium selenite, and sodium selenate) compounds. We utilized aqueous Hg/Se dosing molar ratios that were either above, below, or equal to 1 and measured the internal nematode total Hg and Se concentrations for the highest concentrations of each Se compound. Observed interactions were complicated, differed between Se and Hg compounds, and included greater-than-additive, additive, and less-than-additive growth impacts. Biologically significant interactions were only observed when the dosing Se solution concentration was 100-25,000 times greater than the dosing Hg concentration. Mitigation of growth impacts was not predictable on the basis of internal Hg/Se molar ratio; improved growth was observed at some internal Hg/Se molar ratios both above and below 1. These findings suggest that future assessments of the Hg and Se relationship should incorporate chemical compound into the evaluation.

Grain Accumulation of Selenium Species in Rice (Oryza sativa L.)

Science.gov (United States)

Selenium (Se) is an essential micronutrient in which up to 1 billion people worldwide are deficient, causing a range of health disorders and potentially an increased risk of certain cancers. Consequently, there is much interest in Se biofortification of rice, the staple food for...

Selenium determination in cereal plants and cultivation soils by radiochemical neutron activation analysis

International Nuclear Information System (INIS)

Galinha, C.; Freitas, M.C.; Anawar, H.M.; Pacheco, A.M.G.; Kamenik, J.; Kucera, J.; Coutinho, J.; Macas, B.; Almeida, A.S.

2012-01-01

Selenium (Se) is an essential micronutrient for human health but it is deficient in at least 1 billion people around the globe. Cereals are by far the most significant agricultural crops, not only on a gross tonnage basis, but also by what they represent in terms of energy supply and dietary intake for human nutrition worldwide. Portugal is no exception to such pattern. The Portuguese situation is difficult to assess though, due to scarce information and lack of consistent studies on the subject. In these terms, the Se status of major cereals and their cultivation soils are dealt with herein. Two species of wheat-bread and durum wheat-were sown at the end of November 2009, and then sampled in different growth stages. Rye was collected during harvest season, and cultivation soils were analyzed as well. Se results were within the range of: 100-225 ng g -1 for soils; 3-55 ng g -1 for durum wheat; 6-80 ng g -1 for bread wheat; and 4-30 ng g -1 for rye. Accuracy of the RNAA procedure was proved by analysis of reference materials NIST-SRM 1515 and NIS-SRM 8433. (author)

Selenium Sulfide

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Selenium sulfide, an anti-infective agent, relieves itching and flaking of the scalp and removes the dry, ... Selenium sulfide comes in a lotion and is usually applied as a shampoo. As a shampoo, selenium ...

The effect of catch crop species on selenium availability for succeeding crops

DEFF Research Database (Denmark)

Stavridou, Eleftheria; Young, Scott D.; Thorup-Kristensen, Kristian

2012-01-01

2007–10 investigated the ability of catch crops (Italian ryegrass, fodder radish and hairy vetch) under different fertiliser regimes to reduce soil Se content in the autumn and to increase its availability in spring to the succeeding crop. Results and Conclusions The catch crops (Italian ryegrass...... and fodder radish) increased water-extractable Se content in the 0.25–0.75msoil layer in only one of the experiments. Selenium uptake by the catch crops varied between 65 and 3263 mg ha−1, depending on species, year and fertilisation treatment; this corresponded to 0.1–3.0% of the water-extractable soil Se......Background and Aims Selenium (Se) is an essential nutrient for humans and animals. In order to ensure an optimal concentration of Se in crops, Se fertilisers are applied. Catch crops may be an alternative way to increase Se concentrations in vegetables. Methods Three experiments in Denmark between...

Radio protective effects of selenium on rats

International Nuclear Information System (INIS)

Bakir, A.; Alya, G

2005-11-01

Potential radio-protective effects of different selenium supplement concentrations of 4, 8, 15 and 30 ppm were evaluated in rats. Four groups of rats were administered different concentrations of selenium in drinking water for 30 days before irradiation starting from the ablactation which considered as day 0. The results showed that the sodium selenite of 4 ppm and 8 ppm enhance the 30-day survival of irradiated rats at 7 Gy ( sup 6 sup 0 Co source, whole body irradiation dose rate of 1 Gy x min sup - sup 1) compared to the control group. The mean cumulated probability of survival of rats was 69%+-6 (mean+-S.E.) and 77%+-6 in 4 and 8 ppm groups, respectively, versus 42%+-9 for control group (P<0.001). It was also indicated that sodium selenite with concentrations of 15 and 30 ppm had no significant reduction in mortality. The mean cumulated probability of survival of rats was 50%+-12 (P=0.39) and 49%+-14 (P=0.04), respectively. The toxic effects of selenium were observed at 15 ppm and 30 ppm, survivals after 30 days of selenium intake were 76% and 46%, respectively. It was concluded that 4 and 8 ppm sodium selenite have a radio-protective effect. 15 and 30 ppm sodium selenite had no radio-protective effects in rats, this may be due to a synergism of toxicity and radiation effects. (author)

The effect of dietary selenium supplementation on meat quality of broiler chickens

Directory of Open Access Journals (Sweden)

Miezeliene, A.

2011-01-01

Full Text Available Currently there is a focus on the development of functional poultry products capable of enrichment by selenium, vitamin E, iodine and fatty acids of the third order. Since there is a lack of data about various selenium sources and its synergistic effect on sensory and other properties of vitamin E enriched poultry, the objective of this research was to examine the effect of addition of selenium in broilers diet on meat quality. The amount of Se in the diet was increased from 0.15 mg.kg-1 feed (control group to 0.5 mg.kg-1 feed. Addition of Se had no significant effect (p > 0.05 on cooking and thawing losses, as well as on the majority of sensory attributes, adhesiveness, cohesiveness of chicken breast samples. Aftertaste (p < 0.05, hardness (p < 0.001 and resilience (p < 0.001 of the texture of the samples increased along with the increased amount of Se in bird diet. Mean values of the sensory attributes of thigh muscles showed no significant differences among the samples in case of intensities of odor and taste attributes; however, firmness and chewiness of the tested samples increased by increasing the amount of Se in the feed (p > 0.05. In addition, Se did not have significant influence on meat cooking or thawing losses. The results of this study showed that 0.15 mg and 0.5 mg of selenium in complex with 40 mg of vitamin E could be added to broiler diet without having negative effect on technological or sensory properties of the broiler meat and acceptability.

Selenium speciation in urine by ion-pairing chromatography with perfluorinated carboxylic acids and ICP-MS detection

DEFF Research Database (Denmark)

Gammelgaard, Bente; Bendahl, L.; Sidenius, U.

2002-01-01

Five aqueous standards, selenomethionine (SeMet), methylselenomethionine (MeSeMet), methylselenocysteine (MeSeCys), selenogammaaminobutyric acid (SeGaba) and the trimethylselenonium ion (TMSe), were separated in ion-pairing chromatographic systems based on perfluorinated carboxylic acids in metha...... were major compounds in urine samples-even after massive consumption of selenium-containing supplements. The selenium species in the urine samples showed a limited stability, as they changed during storage at +4 degreesC as well as -18 degreesC...... of between 2.3 and 5.1 pg. Urine samples from different individuals before and during supplementation with selenomethionine were analysed. Several species were separated in the different urine samples. A major component eluting at the beginning of the chromatogram was predominant in many samples, especially...... after selenium consumption. This species was not identified and solid phase extraction experiments suggested that it was neutral. When different urine samples were spiked with the available standards, co-elution of species with TMSe, MeSeMet or SeMet was observed in some samples. None of these species...

Selenium promotes sulfur accumulation and plant growth in wheat (Triticum aestivum)

Science.gov (United States)

Selenium (Se) is an essential micronutrient for animals and humans and a target for biofortification in crops. Sulfur (S) is a crucial nutrient for plant growth. To gain better understanding of Se and S nutrition and interaction in plants, the effects of Se dosages and forms on plant growth as well ...

Plasma levels of selenium-containing proteins in Inuit adults from Nunavik.

Science.gov (United States)

Achouba, Adel; Dumas, Pierre; Ouellet, Nathalie; Lemire, Mélanie; Ayotte, Pierre

2016-11-01

Selenium (Se) is highly abundant in marine foods traditionally consumed by Inuit of Nunavik (Northern Quebec, Canada) and accordingly, their Se intake is among the highest in the world. However, little is known regarding the biological implications of this high Se status in this Arctic indigenous population. We used a method combining affinity chromatography and inductively coupled plasma-mass spectrometry with quantification by post-column isotope dilution to determine total Se levels and concentrations of Se-containing proteins in archived plasma samples of Inuit adults who participated to the 2004 Nunavik Inuit Health Survey (N = 852). Amounts of mercury (Hg) associated with Se-containing proteins were also quantified. Results show that glutathione peroxidase 3 (GPx3), selenoprotein P (SelP) and selenoalbumin (SeAlb) represented respectively 25%, 52% and 23% of total plasma Se concentrations. In addition, small amounts of Hg co-eluted with each Se-containing protein and up to 50% of plasma Hg was associated to SelP. Total plasma Se concentrations (median = 139 μg L− 1; interquartile range (IQR) = 22.7 μg L− 1) were markedly lower and less variable than whole blood Se concentration (median = 261 μg L− 1, IQR = 166 μg L− 1). A non linear relation was observed between whole blood Se and plasma Se levels, with plasma Se concentrations leveling off at approximately 200 μg L− 1, whereas 16% and 3% of individuals exhibited whole blood concentrations higher than 500 μg L− 1 and 1000 μg L− 1, respectively. In contrast, a linear relationship was previously reported in communities consuming Brazil nuts which are rich Se, mainly present as selenomethionine. This suggests that a different selenocompound, possibly selenoneine, is present in the Arctic marine food chain and accumulates in the blood cellular fraction of Inuit.