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Sample records for selenium se content

  1. 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)

  2. Selenium content of mushrooms.

    Science.gov (United States)

    Stijve, T

    1977-07-29

    The selenium contents of 83 species of wild mushrooms were determined by oxygen combustion of the sample, followed by conversion of selenite to bromopiazselenol and final estimation by electron capture gas-liquid chromatography. Selenium concentration were found to range from 0.012-20.0 mg/kg dry weight. Selenium content was species-dependent. High concentrations were found in Agaricaceae and in certain Boletaceae of the genus Tubiporus, whereas in Russulaceae, Amanitaceae and Cantharellaceae selenium-rich species were absent or rare. Ascomycetes and all mushrooms growing on wood had a very low selenium content. The highest selenium concentrations (up to 20 ppm) were found in Boletus (Tubiporus) edulis, a most popular edible mushroom. Analyses of various parts of carpophores of B. edulis, Suillus luteus and Amanita muscaria indicate that in all three species the stalk contains less selenium than the fleshy part of the cap. In Boletus and Suillus the highest selenium content was found in the tubes.

  3. 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

  4. Effect of Se-enriched Organic Fertilizers on Selenium Accumulation in Corn and Soil

    Directory of Open Access Journals (Sweden)

    LI Sheng-nan

    2015-12-01

    Full Text Available The effect of two Se-enriched organic fertilizers (cow dung and rice straw biochar on selenium accumulation of corn growing in selenium deficient soil was studied with pot experiment. The results showed that corn accumulated more selenium and the selenium was much easier to convert from root to shoot in the corn plant with the application of Se-enriched cow dung than Se-enriched rice straw biochar. With the application of more organic fertilizer such as 25 t·hm-2 Se-enriched cow dung or 40 t·hm-2 Se-enriched rice straw biochar, the accumulation of selenium and growth status of corn were getting better than the other treatments. At the same time, as the application amount of Se-enriched organic fertilizers (cow dung and rice straw biochar increased, the total selenium content in the soil also increased, which positively correlated with each other.

  5. 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

  6. Selenium content in wheat and estimation of the selenium daily intake in different regions of Algeria

    International Nuclear Information System (INIS)

    Beladel, B.; Nedjimi, B.; Mansouri, A.; Tahtat, D.; Belamri, M.; Tchanchane, A.; Khelfaoui, F.; Benamar, M.E.A.

    2013-01-01

    In this work, we have measured the selenium content in wheat produced locally in eight different regions of Algeria from east to west, and we have established the annual consumption of selenium for five socio-professional categories. Instrumental neutron activation analysis is used. The selenium levels in wheat samples varied from 21 (Tiaret) to 153 μg/kg (Khroub), with a mean value about 52 μg/kg. The mean of selenium daily consumption from ingestion of wheat per person in the eight regions varied from 32 to 52 μg/day which is close to the minimal FAO recommendation. - Highlights: ► Cereals and cereal products represent a staple food in Algeria. ► The objective of this study is to determine the Se intake in wheat produced locally. ► The concentration of Se in the wheat reflects the level of the Se in regional soils. ► The mean of Se daily consumption is close to the minimal WHO/FAO recommendation.

  7. Selenium Content, Influential Factors Within the Plant and the Transformation of Different Selenium Specification

    Directory of Open Access Journals (Sweden)

    LIU Yuan-yuan

    2014-12-01

    Full Text Available The paper collected relevant literatures on selenium and explored the function to plant, selenium content, influential factors and selenium specification and transformation. We believed that there should be more deep researches on function of selenium to plant. Approaches of molecular, genetic engineering and isotope could be employed to breed selenium rich crops and possibilities in practice. More efforts should be spent on the technologies research for improving selenium level in crops under natural soil conditions to sustainably utilize the selenium resources.

  8. 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...

  9. Selenium content of foods purchased or produced in Ohio.

    Science.gov (United States)

    Snook, J T; Kinsey, D; Palmquist, D L; DeLany, J P; Vivian, V M; Moxon, A L

    1987-06-01

    Approximately 450 samples of about 100 types of foods consumed by rural and urban Ohioans were analyzed for selenium. Meat, dairy products, eggs, and grain products produced in Ohio have considerably lower selenium content than corresponding products produced in high selenium areas, such as South Dakota. Retail Ohio foods with interregional distribution tended to be higher in selenium content than corresponding foods produced in Ohio. Best sources of selenium in Ohio foods commonly consumed were meat and pasta products. Poor sources of selenium were fruits, most vegetables, candies, sweeteners, and alcoholic and nonalcoholic beverages. Establishment of an accurate data base for selenium depends on knowledge of the interregional distribution of foods, the selenium content of foods at their production site, and the selenium content of foods with wide local distribution.

  10. Direct solution-phase synthesis of Se submicrotubes using Se powder as selenium source

    International Nuclear Information System (INIS)

    Yan Shancheng; Wang Haitao; Zhang Yuping; Li Shuchun; Xiao Zhongdang

    2009-01-01

    The selenium submicrotubes were directly prepared using Se powder as selenium source by microwave-assisted method. Field-emission scan electron microscopy (FESEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD) were adopted to characterize the as-prepared products. The results of high-resolution transmission electron microscopy (HRTEM) and XRD pattern proved that the selenium submicrotubes were single crystalline in nature and [0 0 1] oriented. A possible growth mechanism of the selenium submicrotubes was proposed. The effects of the experimental conditions, such as alkaline concentration and solvent properties, on the morphology and dimension of the products have also been discussed

  11. Selenium content in milk and diary samples

    International Nuclear Information System (INIS)

    Kira, Carmen S.; Maihara, Vera A.

    2005-01-01

    Food is the primary source of Se for human beings. As such determining Se levels in foodstuffs become very important. However, information concerning Se levels in different sources of nutrition in different country, particularly in Brazil, is limited. Instrumental Neutron Activation Analysis (INAA) has been used to effectively determine micronutrient levels in foodstuffs, such as milk and dairy samples. The advantage of using the INAA technique is that the samples do not require previous dissolution before analysis. In this study, INAA was applied to determine Se concentration in milk and dairy products. The samples were acquired in the markets of Sao Paulo city. After a 8-hour irradiation in the research reactor IEA-R1, selenium was analyzed by gamma-ray spectrometry. Methodology validation was done analyzing NIST reference materials (Whole Milk Powder and Non Fat Milk Powder). Se concentrations in the sample analyzed were below 0.300 μg g -1 . (author)

  12. Selenium

    Science.gov (United States)

    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

  13. 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)

  14. Bio-transformation of selenium in Se-enriched bacterial strains of Lactobacillus casei.

    Science.gov (United States)

    Kurek, Eliza; Ruszczyńska, Anna; Wojciechowski, Marcin; Łuciuk, Anna; Michalska-Kacymirow, Magdalena; Motyl, Ilona; Bulska, Ewa

    Selenium is an element of very great importance for the proper functioning of the human body, mainly due to its antioxidant properties. Selenium exhibits a preventive effect in the case of cardiovascular disease, the immune system, male infertility and inhibits the toxic action of other agents. Selenium is important for Hashimoto's disease. Intake of selenium in the diet slows the aging process. The biological and toxicological effects of selenium strongly depend on its chemical form. Some organisms for example: plant, yeast, are capable of metabolizing low bioavailable selenium compounds (inorganic selenium) into its high bioavailable forms (organic selenium). The aim of this study was to investigate the bio-transformation of selenium by Lactobacillus bacteria towards the characterisation of selenium metabolites. The speciation of selenium was evaluated by high performance liquid chromatography with inductively coupled plasma mass spectrometry detector. The extraction of selenium species from lyophilized bacteria was executed with water, the mixture of lipase and protease, as well as lisozyme and sodium dodecyl sulphate. All investigated bacteria strains cultivated in the presence of Na2SeO3 effectively uptake selenium. Surprisingly, none of the applied extraction media exhibited a strong power to release the majority of the uptaken selenium compounds. Thus a maximum of 10% of the selenium was extracted from bacteria exposed to the enzymes. However, it was found that Lactobacillus bacteria are able to metabolize inorganic ions of selenium (IV) into Se-methionine, Se-methyloselenocysteine and other unidentified forms. The study confirmed the ability of probiotic bacteria to biotransform inorganic selenium into its organic derivatives. Therefore, Se-enriched bacteria can be considered as an addition to the functional food. selenium speciation, extraction procedure, Lactobacillus casei bacteria, Lactic acid bacteria (LAB), HPLC ICP-MS, functional food.

  15. Relationship between soil contents and plasma levels of selenium ...

    African Journals Online (AJOL)

    The soil contents of trace elements selenium, chromium and manganese were measured to determine their impact on the plasma levels of 160 healthy adult Nigerians in five different experimental locations in Cross River and Akwa Ibom States, South - South Nigeria. The mean (±SD) soil selenium, chromium and ...

  16. Production of urinary selenium metabolites in the rat following 75SeO32- administration

    International Nuclear Information System (INIS)

    Kiker, K.W.; Burk, R.F.

    1974-01-01

    Urinary metabolites of 75 Se were studied in male Holtzmann rats fed a Torula yeast diet with either no selenium (basal) or 0.5 ppM selenium (selenium) added as sodium selenite. The animals were anesthetized, a ureter was cannulated, and 20 μCi of 75 SeO 3 2- were injected intraportally. Only a small fraction (1.3 percent) of the injected 75 Se was excreted in 6 h by animals fed the basal diet but 13.3 percent was excreted by animals fed the selenium diet. Paper chromatography showed that both groups excreted mostly inorganic 75 Se in the first 10 min. A decrease in 75 Se excretion followed, and then, 70 min after the collection was started, the selenium diet group had an increase in 75 Se excretion which persisted for the rest of the 6 h and consisted mainly of the organic metabolites trimethylselenonium ion and U-2. 75 Se excretion remained low in the basal diet group. Liver uptake and release of 75 Se in the 1 h following intraperitoneal 75 SeO 3 2- injection was much greater in the selenium diet rats than in the basal diet rats. These results suggest that the greater excretion of 75 Se by rats fed the selenium diet than that by rats fed the basal diet was due to increased production of organic urinary selenium metabolites by the liver. (U.S.)

  17. Accumulation of selenium and assessment of the microelements contents in rape spring on meadow-black soil

    International Nuclear Information System (INIS)

    Ermokhin, Yu.I.; Sindireva, A.V.

    2008-01-01

    Quantitative correlation was installed as a result of work between arrival of the selenium on meadow-black soil and contents of this element in green mass of the rape spring. Correlation between the contents of Se and Cd, Ni, Zn in green mass at the rape spring was studied. In this article the assessment of the microelements contents depending on doses and methods of using selenium is offered

  18. 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.

  19. 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

  20. 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.

  1. Loss of selenium-binding protein 1 decreases sensitivity to clastogens and intracellular selenium content in HeLa cells

    Science.gov (United States)

    Selenium-binding protein 1 (SBP1) is not a selenoprotein but structurally binds selenium. Loss of SBP1 during carcinogenesis usually predicts poor prognosis. Because genome instability is a hallmark of cancer, we hypothesized that loss of SBP1 modulates cellular selenium content and the response of ...

  2. COMPARISON OF DETERMINING METHODS REGARDING SELENIUM CONTENT IN WHEAT PLANT

    Directory of Open Access Journals (Sweden)

    Mihaela Monica Stanciu-Burileanu

    2010-01-01

    Full Text Available As a metallic chemical element, selenium has received special attention from biologists because of its dual role as a trace element essential and toxic. The important part of enzymes that protect cells against the effects of free radicals that are produced during normal metabolism of oxygen. Also, selenium is essential for normal immune system and thyroid gland, The concentration of selenium in the soil, which varies by region, determines the default concentration of selenium in plants growing in the soil.The purpose of this paper is to present methods of comparison, dry oxidation at 450ºC and wet digestion – digestion with acids in high concentrations at microwave system digestion, for determining selenium content from wheat samples collected from the south-eastern part of Romania, namely Bărăgan Plain and Central-South Dobrogea. Selenium separation and dosage from obtained extracts carry out through a selective hydride generation atomic absorption spectrophotometry. With the software SURFER, a tendency map of selenium distribution was drawn.

  3. 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...

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

    Directory of Open Access Journals (Sweden)

    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

  5. Effect of selenium deficiency on 75Se and 45Ca metabolism in chicks

    International Nuclear Information System (INIS)

    Edwardly, J.S.

    1981-01-01

    Two hundred, 1 day old broiler chicks were used to study the effect of selenium deficiency on 75 Se and 45 Ca metabolism in chicks. The chicks were randomly divided into five groups. One group was fed a purified basal diet low in selenium ( 75 Se or 45 Ca. Levels of radioisotopes in blood and tissue, as well as total body excretion of radioactivity were determined. Whole body retention of 75 Se was significantly higher (p 45 Ca was significantly higher in selenium deficient chicks than in supplemented animals. Total Ca concentration in muscle was also higher in this group. Studies of red cell uptake of 75 Se demonstrated a clear difference between Se repleted and selenium deficient groups. (author)

  6. 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.

  7. Preliminary Study on the Standard of Selenium Content in Agricultural Products

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhi-yuan; YOU Yong; GUO Qing-quan; WANG Yong-hong; DENG Shi-lin

    2012-01-01

    With the improvement of living standards, people pay more attention to the agricultural products with health protection function, and the selenium-rich agricultural products attract more and more consumers. The main biological role of selenium is to resist oxidation and inflammatory response, mainly focusing on resisting aging, preventing cardiovascular disease, protecting eyesight, counteracting or destroying the toxic properties, preventing cancer and thyroid disease. In most areas of China, there is a widespread shortage of selenium, thus producing selenium-rich agricultural products to provide natural selenium-rich health food to the areas in need of selenium, has gradually become a new hot spot of China’s health food industry, but high content of selenium in food is detrimental to human body, even leads to selenium intoxication, and artificially adding inorganic selenium is difficult to guarantee that the selenium content of agricultural products is not exceeded. According to human body’s daily demand for selenium in dietetics and the content of selenium in agricultural products in the Chinese food composition table, we put forward the recommendations on the standard of selenium in agricultural products, in order to provide the basis for China to formulate the health standard of selenium content in selenium-rich agricultural products.

  8. Rubidium contents in erythrocyte of children, rice and soil in the areas with different selenium status

    International Nuclear Information System (INIS)

    Liu Nianqing; Zhao Shunying; Qian Qinfang; Zhu Lianzhen; Piao Jianhua

    1997-01-01

    Rubidium concentration of erythrocyte of healthy children aged from 6-11 years living in four areas of Sichuan Province with different selenium status was measured by PIXE and the results show that the Rb concentration in erythrocyte for the Keshan Disease area is two times more than other three areas. Meanwhile the glutathione peroxidase (GSHPx) activity of erythrocyte was determined and the results confirm that children in the Keshan Disease area are really with selenium deficiency. The Rb contents in rice and soil samples from the Keshan Disease area and the Se-deficiency area but with Se-supplementation to the inhabitants, were tested by INNA. It was found that Rb contents in rice and soil from the former area were much higher than those from the latter. This result indicates that Rb in erythrocyte of children is mainly taken from staple food (rice) and that a higher Rb level in soil is probably another environmental factor causing the Keshan Disease

  9. Distribution and reuse of 76Se-selenosugar in selenium-deficient rats

    International Nuclear Information System (INIS)

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

    2006-01-01

    Nutritional selenium compounds are transformed to the common intermediate selenide and then utilized for selenoprotein synthesis or excreted in urine mostly as 1β-methylseleno-N-acetyl-DD-galactosamine (selenosugar). Since the biological significance of selenosugar formation is unknown, we investigated their role in the formation of selenoenzymes in selenium deficiency. Rats were depleted of endogenous natural abundance selenium with a single stable isotope ( 82 Se) and then made Se-deficient. 76 Se-Selenosugar was administered intravenously to the rats and their urine, serum, liver, kidneys and testes were subjected to speciation analysis with HPLC inductively coupled argon plasma mass spectrometry. Most 76 Se was recovered in its intact form (approximately 80% of dose) in urine within 1 h. Speciation analysis revealed that residual endogenous natural abundance selenium estimated by 77 Se and 78 Se was negligible and distinct distributions of the labeled 76 Se were detected in the body fluids and organs without interference from the endogenous natural abundance stable isotope. Namely, intact 76 Se-selenosugar was distributed to organs after the injection, and 76 Se was used for selenoprotein synthesis. Oxidation to methylseleninic acid and/or hydrolysis of the selenoacetal group to methylselenol were proposed to the transformation of selenosugar for the reuse. Effective use of an enriched stable isotope as an absolute label in hosts depleted of natural abundance isotopes was discussed for application in tracer experiments

  10. 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...

  11. Effect of irradiation on sod activity and selenium content in garlic

    International Nuclear Information System (INIS)

    Xu Weimin; Zheng Anjian; Yan Jianmin; Cao Qingsui; Wu Haihong; Cao Shifeng

    2006-01-01

    The effects of irradiation at 0.1 kGy, 1.0 kGy on SOD activity and the content of total selenium, inorganic selenium, organic selenium in garlic (Allium sativum L.) stored at 10 degree C or 25 degree C were investigated. The results indicated that irradiation treatment with 0.1 kGy, 1 kGy significantly slowed the reduction of SOD activities in garlic stored at 10 degree C or 25 degree C, while the treatment irradiation had no influence on the content of all kinds of selenium. But the garlic stored at 25 degree C had higher content of total selenium, inorganic selenium, organic selenium than that in garlic stored at 10 degree C. (authors)

  12. 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.

  13. Examination of the selenium content of wheat grasses produced in different soil types in Csik Basin

    Directory of Open Access Journals (Sweden)

    Tamás M.

    2015-01-01

    Full Text Available In the course of the research, we determined selenium and dry matter content of 35 wheat grass and 35 wheat seed samples. The selenium content of the preparation plant probes was measured by spectrofluorimetric determination (λexcitation = 380 nm, λemission = 519 nm of the resulted piazselenol complex. It was established that between the selenium content of the wheat grass and wheat seed the correlation coefficient was 0.36 at p = 0.05 level, which indicates a medium-close correlation. Similarly, there was a medium-close correlation between the selenium content of the wheat grass calculated on dry-matter basis and total selenium content of the wheat, with a correlation coefficient of 0.40 at p = 0.02 level. Afterwards, beside the selenium content, we measured the selenomethionine content by ion-exchange chromatography and highperformance liquid chromatography, and the organic selenium content was calculated. A very close correlation was established between the total selenium, selenomethionine and calculated organic selenium content of wheat (the correlation coefficients were between 0.92 and 0.99 at p = 0.01 level. The correlation between the selenomethionine content of wheat grass and wheat seed was very weak (r = 0.23.

  14. Selenium

    Science.gov (United States)

    ... Health Information Supplement Fact Sheets Frequently Asked Questions Making Decisions What you Need To Know About Supplements Dietary ... understand how selenium in food and dietary supplements affects heart health. Cognitive decline Blood selenium levels decrease as people age, ...

  15. Increase in the selenium content of extra virgin olive oil: quantitative and qualitative implications

    Directory of Open Access Journals (Sweden)

    D’Amato, R.

    2014-06-01

    Full Text Available The biofortification of food crops for human consumption is a direct strategy increasing dietary intake of selenium (Se. The aim of this study was to evaluate the possibility of increasing the Se content of extra virgin olive oil (EVOO by spraying the olive tree canopy with sodium selenate and the effect of the increase in Se on the chemical properties and sensory characteristics of the EVOO. Se treatments were up to 50 times more effective in enhancing Se content in the EVOO compared with the untreated controls. Se concentration in all the EVOO samples can be considered adequate and useful for providing the human diet with the correct dose of Se. Se-enriched EVOO showed a significant increase in pigment and phenol content. Also, Se treatment does not produce negative effects on fruit characteristics or the sensory quality of EVOO.La biofortificación de cultivos alimenticios para el consumo humano es una estrategia directa para aumentar la ingesta de selenio (Se en la dieta. El objetivo de este estudio fue evaluar la posibilidad de aumentar el contenido de Se en aceites de oliva virgen extra (AOVE pulverizando la copa de los olivos con selenato de sodio y el efecto del aumento en el contenido de Se en las propiedades químicas y características sensoriales del AOVE. Los tratamientos con Se fueron muy eficaces consiguiendo aumentar el contenido de Se en el AOVE hasta 50 veces más en comparación con los controles no tratados. La concentración de Se en todas las muestras EVOO puede considerarse adecuada y útil para proporcionar a la dieta humana con la dosis correcta de Se. EVOO-Se enriquecido mostró un aumento significativo en pigmentos y contenido de fenoles. Además, el tratamiento de Se no implica efectos negativos sobre caracteristicas frutales ni sobre la calidad sensorial de AOVE.

  16. Effect of selected method of meat technological treatment on selenium content in mutton

    International Nuclear Information System (INIS)

    Nowosad, R.; Simoni, J.; Tyszkiewicz, B.

    1977-01-01

    Measurements were carried out of a radioisotope 75 Se content in mutton meat exposed to some technological treatments (soaking in tap water for 24 hours, pickling for 14 days, boiling for 1 hour) and to 24-hour soaking in 1% solutions of some organic acids used for alimentary purposes (lactic acid, citric acid, and acetic acid). The lowest decrease of radioactivity (11,69%) was noted following 24-hour soaking in tap water while the highest loss of selenium (41,69%) was measured after 24-hour soaking of granulated meat in 1% solution of lactic acid. The application of the same technological measures to the homogeneous force-meat resulted in higher loss of radioselenium in samples under test. The lowest decrease of radioactivity (19.19%) was observed following 1-hour boiling while the highest loss of selenium (60.81%) was measured after 24-hour soaking in 1% soaking in 1% solution of lactic acid. (author)

  17. 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 ...

  18. Influence of long-term fertilization on the selenium content of calcareous chernozem soil.

    Science.gov (United States)

    Blagojević, S; Jakovljević, M; Zarković, B

    1998-01-01

    Available data on the selenium (Se) content in Yugoslavian soils indicate that the element is present in small amounts (chernozem soil. The experiment of the Maize Research Institute in Belgrade was set up in 1971 and soil samples were examined by chemical analysis after 23 years. The following important conclusions can be drawn based on the analytical data obtained. The total content of Se in the investigated experimental variants in calcareous chernozem soil ranges from 166 to 593 microg/kg. All the variants had a higher content of Se than soil samples taken before the experiment was set up. Comparison with the control (variant without fertilizers) indicated that the Se content increased in the experimental variants where farmyard manure had been applied. This effect was noticed to a depth of 80 cm. Application of farmyard manure should be considered as a means of increasing the levels of Se in Se-deficient soil. Correlation coefficients between total Se content in the soil and some important agrochemical properties of the investigated soils are presented in this paper.

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

    Science.gov (United States)

    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.

  20. 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.

  1. Loss of Selenium-Binding Protein 1 Decreases Sensitivity to Clastogens and Intracellular Selenium Content in HeLa Cells.

    Science.gov (United States)

    Zhao, Changhui; Zeng, Huawei; Wu, Ryan T Y; Cheng, Wen-Hsing

    2016-01-01

    Selenium-binding protein 1 (SBP1) is not a selenoprotein but structurally binds selenium. Loss of SBP1 during carcinogenesis usually predicts poor prognosis. Because genome instability is a hallmark of cancer, we hypothesize that SBP1 sequesters cellular selenium and sensitizes cancer cells to DNA-damaging agents. To test this hypothesis, we knocked down SBP1 expression in HeLa cervical cancer cells by employing a short hairpin RNA (shRNA) approach. Reduced sensitivity to hydrogen peroxide, paraquat and camptothecin, reactive oxygen species content, and intracellular retention of selenium after selenomethionine treatment were observed in SBP1 shRNA HeLa cells. Results from Western analyses showed that treatment of HeLa cells with selenomethionine resulted in increased SBP1 protein expression in a dose-dependent manner. Knockdown of SBP1 rendered HeLa cells increased expression of glutathione peroxidase-1 but not glutathione peroxidase-4 protein levels and accelerated migration from a wound. Altogether, SBP1 retains supplemental selenium and sensitizes HeLa cancer cells to clastogens, suggesting a new cancer treatment strategy by sequestering selenium through SBP1.

  2. 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.)

  3. 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.)

  4. Resistance, accumulation and transformation of selenium by the cyanobacterium Synechocystis sp. PCC 6803 after exposure to inorganic SeVI or SeIV

    International Nuclear Information System (INIS)

    Gouget, B.; Avoscan, L.; Collins, R.; Carriere, M.; Sarret, G.

    2005-01-01

    Our purpose was to investigate the ability of Synechocystis sp. PCC 6803, a photosynthetic prokaryote isolated from fresh water, to resist, incorporate and reduce the oxidized forms of selenium including selenite and selenate, the major selenium species present in aquatic systems. Selenium speciation and the chemical intermediates during selenium transformation were determined by X-ray absorption near edge structure (XANES) spectroscopy. The possible internalisation pathways involving selenium and the metabolic fate of selenate and selenite were examined. Selenate metabolism seemed to proceed via the sulfate reduction pathway resulting in the formation of the R-Se-H, R-Se-R and R-Se-Se-R species. The transformation of selenate to toxic amino acids may explain the high sensitivity of Synechocystis to selenate. Several mechanisms of selenium reduction seem to complete during selenite assimilation. A specific mechanism may transform internalised selenite into selenide and, subsequently induce the biosynthesis of selenoproteins. A non-specific mechanism may interfere with thiols, such as glutathione in the cell cytoplasm, or with proteins in the periplasm of the bacteria, notably thioredoxins. Several hypotheses concerning the complex transformation of selenium in Synechocystis could therefore be proposed. (orig.)

  5. 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.

  6. Development of in-plant reference material for composition of chinese cabbage with certified selenium content

    Directory of Open Access Journals (Sweden)

    D. A. Chupahin

    2014-01-01

    Full Text Available In-plant reference material for composition of Chinese cabbage with certified selenium content was developed for accuracy control of the results of selenium determination and within-laboratory quality control of analytical work in the analysis of food raw material.

  7. 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.

  8. 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.

  9. 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...

  10. 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

  11. Selenium content in tissues and meat quality in rabbits fed selenium yeast

    Czech Academy of Sciences Publication Activity Database

    Dokoupilová, A.; Marounek, Milan; Skřivanová, V.; Březina, P.

    2007-01-01

    Roč. 52, č. 6 (2007), s. 165-169 ISSN 1212-1819 Institutional research plan: CEZ:AV0Z50450515 Keywords : rabbits * selenium * meat Subject RIV: GH - Livestock Nutrition Impact factor: 0.633, year: 2007

  12. Investigations of the Connection between Vitamin E Deficiency and the Selenium Content in Animal Organs

    Energy Technology Data Exchange (ETDEWEB)

    Duftschmid, K. E. [Reaktor-Zentrum Seibersdorf (Austria); Leibetseder, J. [Tierarztliche Hochschule, Vienna (Austria)

    1967-10-15

    The highly toxic effects of selenium have been well known for a long time. Just ten years ago, however, the important role of Se in the prophylaxis of certain pathological symptoms, e.g. in the exudative diathesis of chickens, was recognized. In particular, the connection between Se and vitamin E has attracted considerable attention. Detailed feeding experiments with laboratory animals have shown some relation between the symptoms of vitamin E deficiency and Se, but up to now the underlying mechanisms have remained obscure. To contribute to clearing up these questions we have used activation analysis to determine whether a deficiency of vitamin E alters the Se content of certain typical organs. For this purpose 40 Cobb's one-day-old chicks were bred in batteries. One group was fed with vitamin-E-free standard diet; the other group was given the same diet but with an additive of 30 ppm of vitamin E. The Se content was 5 ppm in both cases. At an age of three weeks the chicks were killed and preparations of blood, plasma, cerebrum, cerebellum, pectoral muscle, liver, kidney and gonads were taken. In order to assay the Se content of some 600 preparations in a reasonable time a fast method of analysis was chosen using the 17. 5-s {sup 77m}Se. In this way the following advantages were obtained: (i) the short half-life and high activation cross-section made possible a high sensitivity even after very short irradiation times (20 s); (ii) problems arising from the matrix activity (mainly {sup 24}Na) were minimized and a chemical separation was unnecessary. To eliminate the critical influence of the half-life, each sample was irradiated and measured simultaneously with a Se standard using a multichannel analyser with an input facility for two detectors. The statistical evaluation of the measurements showed various interesting results. It was established that the Se content of certain organs is influenced by the vitamin E supply. Thus, the muscle preparations from vitamin

  13. Impact of selenium supply on Se-methylselenocysteine and glucosinolate accumulation in selenium-biofortified Brassica sprouts.

    Science.gov (United States)

    Avila, Fabricio William; Yang, Yong; Faquin, Valdemar; Ramos, Silvio Junio; Guilherme, Luiz Roberto G; Thannhauser, Theodore W; Li, Li

    2014-12-15

    Brassica sprouts are widely marketed as functional foods. Here we examined the effects of Se treatment on the accumulation of anticancer compound Se-methylselenocysteine (SeMSCys) and glucosinolates in Brassica sprouts. Cultivars from the six most extensively consumed Brassica vegetables (broccoli, cauliflower, green cabbage, Chinese cabbage, kale, and Brussels sprouts) were used. We found that Se-biofortified Brassica sprouts all were able to synthesize significant amounts of SeMSCys. Analysis of glucosinolate profiles revealed that each Brassica crop accumulated different types and amounts of glucosinolates. Cauliflower sprouts had high total glucosinolate content. Broccoli sprouts contained high levels of glucoraphanin, a precursor for potent anticancer compound. Although studies have reported an inverse relationship between accumulation of Se and glucosinolates in mature Brassica plants, Se supply generally did not affect glucosinolate accumulation in Brassica sprouts. Thus, Brassica vegetable sprouts can be biofortified with Se for the accumulation of SeMSCys without negative effects on chemopreventive glucosinolate contents. Published by Elsevier Ltd.

  14. 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.

  15. 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

  16. Selenium contents in tobacco and main stream cigarette smoke determined using neutron activation analysis

    International Nuclear Information System (INIS)

    Marica Sorak-Pokrajac; Dermelj, M.; Zdenka Slejkovec; Eskinja, I.

    1994-01-01

    In the domain of the essential trace elements, the role of selenium is extermely important. As one of the volatile elements is can be partly absorbed through the pulmonary system during smoking and transported to different organs of the body. Thus a knowledge of its concentration levels in various sorts of tobacco and in the smoke of commercial cigarettes, as well as in the same type of cigarettes from plants treated with selenium, is of interest for various research fields. The purpose of this contribution is to present reliable quantitative data on selenium contents in tobacco, soil, and main stream cigarette smoke, obtained by destructive neutron activation analysis

  17. Changes in sugar content and related enzyme activities in table grape (Vitis vinifera L.) in response to foliar selenium fertilizer.

    Science.gov (United States)

    Zhu, Shuaimeng; Liang, Yinli; An, Xiaojuan; Kong, Fanchao; Gao, Dekai; Yin, Hongfei

    2017-09-01

    Spraying selenium (Se) fertilizer is an effective method for Se-enriched fruit production. Sugar content in fruit is the major factor determining berry quality. However, changes in sugar metabolism in response to Se fertilizer are unclear. Hence, this study was conducted to identify the effects of Se fertilizer on sugar metabolism and related enzyme activities of grape berries. Additionally, production of leaves with and without Se fertilizer was also investigated. Acid invertase (AI) activity, total soluble sugar and Se content in berries, and photosynthetic rate in leaves produced under Se fertilizer treatments were higher than that of control. Glucose and fructose were the primary sugars in berries, with a trace of sucrose. In both berries and leaves, neutral invertase activity was lower than AI, there was no significant difference in neutral invertase, sucrose synthase and sucrose phosphate synthase between Se fertilizer-treated and control. In berries, AI showed a significant positive correlation with glucose and fructose; also Se content was significantly correlated with sugar content. AI played an important role in the process of sugar accumulation in berries; high AI activity in berries and photosynthetic rate in leaves could explain the mechanism by which Se fertilizer affected sugar accumulation in berries. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  18. 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.

  19. Blood selenium content determination by X-ray fluorescence

    International Nuclear Information System (INIS)

    Mainardi, R.T.

    1987-01-01

    The presence of some elements in small amounts (traces) in the human body is of foremost importance for the prevention and treatment of several diseases. It has been recently shown that traces of selenium in blood are closely related to the occurrence of miotonic distrophy, a muscular disease that is affecting a significant percentage of the population. This work describes a simple procedure to determine selenium in human blood serum by energy dispersive X-ray fluorescence analysis. Final quantification is achieved through the addition of titanium as an internal standard. (Author) [es

  20. 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)

  1. Selenium content of Argentinean infant formulae and baby foods by pseudo-cyclic instrumental neutron activation analysis coupled to Compton suppression

    International Nuclear Information System (INIS)

    Hevia, S.; Chatt, A.

    2013-01-01

    The selenium levels of Argentinean infant formulae and baby food were measured using the 162-keV gamma-ray of 77m Se (t ½ = 17.4 s) by a pseudo-cyclic instrumental neutron activation analysis (PC-INAA) method in conjunction with Compton suppression spectrometry (CSS). For comparison purposes, 5 selected infant formulae were also analyzed for selenium by a radiochemical neutron activation analysis (RNAA) method. The selenium levels for three samples agreed between ±2.8 and 6.5 % while the other two differed by 12 and 17 % which could perhaps be attributed to sample inhomogeneity. The selenium content of cow milk-based infant formulae varied from 42-146 μg kg -1 compared to 52-63 μg kg -1 for soy-based milk formulae. In the case of baby foods, the selenium levels varied from 34 to 74 μg kg -1 . The detection limits for selenium by PC-INAA-CSS for all the samples analyzed in this work were between 8.5 and 65 μg kg -1 depending on the major elements present in the samples, while it was 20 μg kg -1 for the RNAA method. The expanded uncertainty (κ = 2) of the PC-INAA-CSS method was 7.0 % at the end of cycle 4 for a sample containing 73.7 μg kg -1 selenium compared to the RNAA value of 24.2 % for a sample of 67.0 μg kg -1 selenium content. (author)

  2. 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.

  3. 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

  4. INFLUENCE OF SELENIUM CONTENT AND OIL SOURCES IN FEED ON CONCENTRATION OF THYROID GLAND HORMONES AND ELECTROLYTE IN BROILER BLOOD

    Directory of Open Access Journals (Sweden)

    Zlata Kralik

    2014-12-01

    Full Text Available The research aimed to elaborate the influence of designed mixtures used in broilers fattening on the concentration of electrolytes and thyroid gland hormones in the blood.. The research was carried out on 120 male Ross 308 hybrid broilers. The fattening lasted for 42 days. During the first three weeks of fattening broilers were fed standard starter diet containing 22% crude protein and 13.90 MJ/kg ME. During the last three weeks of fattening, broilers were divided into 6 experimental groups, each fed specially prepared finisher diets (P1=6% sunflower oil+0.0 mg Se/kg of feed, P2=6% linseed oil+0.0 mg Se/kg of feed, P3=6% sunflower oil+0.3 mg Se/kg of feed, P4=6% linseed oil+0.3 mg Se/kg of feed, P5=6% sunflower oil+0.5 mg Se/kg of feed, P6=6% linseed oil+0.5 mg Se/kg of feed. Finisher diet was balanced at 18.02% crude protein and 14.40 MJ/kg ME. It was found out that the type of oil in chicken feed influenced to blood pH (P <0.001, whereas selenium level (P=0.014 in the feed, as well as the oil type and selenium level interaction (P<0.001 influenced the concentration of potassium in the blood. Oil type (P=0.037 influenced the concentration of fT3, which was lower in chickens fed mixtures with addition of linseed oil than in the chickens fed sunflower oil added mixtures. Interaction of selenium content and oil type had influence on differences in concentration of fT4 as well as on the ratio of fT3/fT4, (P<0.001, i.e. P=0.021. The research results indicated that oils supplemented to broiler diets and combined with different organic selenium concentrations affected pH, concentration of some electrolytes and thyroid gland hormones in broiler blood, however, all obtained values were within reference range for poultry.

  5. Selenium content of tissues in Finnish infants and adults with various diseases, and studies on the effects of selenium supplementation in neuronal ceroid lipofuscinosis patients

    International Nuclear Information System (INIS)

    Westermarck, T.

    1977-01-01

    A low blood selenium level has previously been observed in healthy inhabitants of Finland. In this study even lower blood selenium values were observed in patients with acrodermatitis enteropathica, dystrophia musculorum progressiva (Duchenne), infantile and juvenile type of neuronal ceroid lipofuscinosis (NCL), severe mental retardation caused by various factors, and myocardial infarction. The selenium content of the brain, heart, kidney and liver in patients of different ages was also determined. The highest selenium level was found in the kidney. The mean liver selenium concentrations in stillborn, premature and full-term neonates were 1.11 plus minus 0.23 (8), 1.21 plus minus 0.17 (12) and 0.93 plus minus 0.16 μg/g dry weight (12) respectively (the number of subjects in parentheses). The selenium values are considerably higher than those in infants of from one to nine months of age and adults, whose liver selenium values were 0.58 plus minus 0.21 (8) and 0.67 plus minus 0.08 μg/g dry weight (8) respectively. The vitamin E levels of serum in patients with NCL, as well as in subjects with severe mental retardation (controls), were low compared with values in healthy normal subjects. Sodium selenite supplementation in patients with NCL produced at least a transitory improvement without causing any toxic effects during one year of administration. (author)

  6. Ultrasound-assisted extraction technique for establishing selenium contents in breast cancer biopsies by Zeeman-electrothermal atomic absorption spectrometry using multi-injection

    International Nuclear Information System (INIS)

    Lavilla, I.; Mosquera, A.; Millos, J.; Cameselle, J.; Bendicho, C.

    2006-01-01

    A solid-liquid extraction method is developed to establish the contents of selenium in breast cancer biopsies. The method is based on the ultrasound-assisted extraction of selenium from pretreated biopsies prior to Se determination by atomic absorption spectrometry with longitudinal-Zeeman background correction. Fifty-one breast biopsies were collected from the Cies Hospital (Vigo, Spain), 32 of which correspond to tumor tissue and 19 to normal tissue (parenchyma). Difficulties arising from the samples analyzed, i.e. small samples mass (50-100 mg), extremely low Se contents and sample texture modification including tissue hardening due to formaldehyde preservation are addressed and overcome. High intensity sonication using a probe together with addition of hydrogen peroxide succeeded in completely extracting Se from biopsies. The multiple injection technique was useful to tackle the low Se contents present in some biopsies. The detection limit was 25 ng g -1 of Se and the precision, expressed as relative standard deviation, was less than 10%. Se contents ranged from 0.08 to 0.4 μg g -1 for parenchyma samples and from 0.09 to 0.8 μg g -1 for tumor samples. In general, Se levels in tumor biopsies were higher as compared with the adjacent normal tissue in 19 patients by a factor of up to 6. Analytical data confirmed Se accumulation in the breast tumors

  7. 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.

  8. Effect of Organic Selenium from Se-enriched Alga (Chlorella spp. on Selenium Transfer from Sows to Their Progeny

    Directory of Open Access Journals (Sweden)

    Martin Svoboda

    2009-01-01

    Full Text Available The study was conducted to determine the efficacy of organic Se from Se-enriched alga Chlorella spp. in placental transfer to piglets. In group A (n = 8 the sows were fed during the gestation a diet supplemented with inorganic Se (sodium selenite, 0.3 mg/kg. In group B (n = 8 the diet of the sows was supplemented with organic Se from Se-enriched alga (0.3 mg/kg. The Se concentrations in the whole blood (P P Chlorella spp. in sows resulted in greater transfer of Se to their progeny.

  9. 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

  10. 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

  11. 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

  12. 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.

  13. 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

  14. Ecological Importance of Insects in Selenium Biogenic Cycling

    Directory of Open Access Journals (Sweden)

    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.

  15. Content of arsenic, selenium, mercury in the coal, food, clay and drinking water on the Zhaotong fluorosis area, eastern Yunnan Province

    Energy Technology Data Exchange (ETDEWEB)

    Luo Kun-li; Li Hui-jie; Chen Tong-bin (and others) [Chinese Academy of Sciences, Beijing (China). Institute of Geographic Sciences and Natural Resources Research

    2008-03-15

    About 160 samples of coal, corn, capsicum and drinking water were collected from the endemic fluorosis area of Zhenxiong and Weixin County, Zhaotong City of Yunnan Province, to determine the arsenic (As), selenium (Se) and mercury (Hg) content by AAF-800. The study found that the As content in the main coal seam from the Late Permian coal mines in Zhaotong City is 8.84 mg/kg and some civil coal can reach 89.09 mg/kg. The Se and Hg in the coal samples of Late Permian is lower, but Se and Hg are more concentrated in the pyritic coal balls and the pyritic gangue of the coal seam. The As content in corn and capsicum dried by coal-burning is more than 0.7 mg/kg, the natural standard amount of arsenic content permitted in food by China. The Se and Hg content in corn dried by coal-burning is lower than the natural standard of Se and Hg content in food in China but the Se and Hg content of capsicum dried by coal-burning exceeds the amount permitted by the natural standard for food in China. Clay, used as an additive for the coal-burning process and as a binder in making briquettes, contains a high content of As, generally more than 16 mg/kg. However, the Se and Hg content of clay itself are low. The As, Se and Hg content of drinking water are lower than the natural standard of As, Se and Hg content in the drinking water. So, there is high-As content coal and high-As content dried corn and capsicum in the endemic fluorosis area of Zhaotong City of Yunnan Province. The high As content of the dried corn and capsicum might have originated from the high arsenic content of burnt coal and clay. 30 refs., 4 tabs.

  16. Iodine and Selenium Contents in Skeletal Muscles of Red Deer (Cervus elaphus, Roe Deer (Capreolus capreolus and Wild Boar (Sus scrofa in the Czech Republic

    Directory of Open Access Journals (Sweden)

    Jaroslav Kursa

    2010-01-01

    Full Text Available The objective of this study was to examine iodine and selenium contents in skeletal muscles of selected species of game animals living in regions with low iodine and selenium contents in the soil and water. Iodine content was determined in 66 samples of skeletal muscles of red deer cut out of the musculus gracilis, 32 samples and 27 samples from the same muscle of roe deer and wild boar, respectively. The shot game animals came from hunting grounds in western and southern regions of the Czech Republic and in Protected Landscape Area Šumava. In red deer muscles the average iodine content was 44.9 ± 15.2 μg I·kg-1 wet weight with the range of 6.9 to 82.0 μg I·kg-1. The lower concentration in roe deer meat with the average 39.3 ± 14.1 μg I·kg-1 and the range from 18.3 to 84.4 μg I·kg-1 may be due to differences between biotopes and food. The average iodine concentration in the musculus gracilis of wild boars was 55.9± 27.0 μg·kg-1 wet weight. Selenium content was determined in 22 samples of red deer, 51 samples of roe deer and 27 samples of wild boar skeletal muscles. The average values of selenium content in the meat of red deer, roe deer and wild boars were 16.2 ± 8.4, 36.9 ± 16.6 and 27.6 ± 19.8 μg Se·kg-1 wet weight, respectively. All three species of game animals are characterised by low content and high variability of selenium concentration in meat with the minimum value 3.9 µg and maximum value 83.3 μg·kg-1 wet weight. The study brings new data on iodine and selenium content in the muscle of game animals in the Czech Republic.

  17. Synthesis of selenium/EDTA-derived porous carbon composite as a Li–Se battery cathode

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Chenhao, E-mail: zhaochenhao123456@163.com; Fang, Shuzhen; Hu, Zhibiao, E-mail: zhibiaohu@163.com; Qiu, Sheng’en; Liu, Kaiyu [LongYan University, College of Chemistry & Materials Science (China)

    2016-07-15

    The carbon substrate with unique 3D macroporous structure has been prepared through the immediate carbonization of ethylenediaminetetraacetic acid (EDTA) and KOH mixture. The porous carbon composed of micro- and small mesoporous (2–5 nm) structure has a BET specific surface area of 1824.8 m{sup 2} g{sup −1}. The amorphous and nanosized Se is uniformly encapsulated into the porous structure of porous carbon using melting diffusion route, and the weight content of Se in target Se/C composite can be as high as ~50 %. As an Li–Se battery cathode, the Se/C composite delivers a reversible (2nd) discharge capacity of 597.4 mAh g{sup −1} at 0.24C and retains a discharge capacity of 538.4 mAh g{sup −1} at 0.24C after 100 cycles. Furthermore, the composite also has a stable capacity of 291.0 mAh g{sup −1} at a high current of 4.8C. The high specific area and good porous size of EDTA-derived carbon substrate may a be responsibility for the excellent electrochemical performances of Se/C composite.

  18. 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.

  19. 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

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

    Directory of Open Access Journals (Sweden)

    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.

  1. 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

  2. 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.

  3. Reference material certification of chinese cabbage composition for selenium, nitrogen, phosphorus and potassium content

    Directory of Open Access Journals (Sweden)

    D. A. Chupakhin

    2016-01-01

    Full Text Available Rationale. The reference material of composition with the established metrological characteristics including a certified value and an expanded uncertainty is necessary to ensure an effective accuracy and precision control of results of element composition determination in food ingredients and products. This paper represents the development of a reference material of food crop composition for selenium, nitrogen, phosphorus and potassium content. Methods. To identify the selenium the hybrid atomic absorption method was used, to identify the nitrogen and phosphorus the photometric method was used, to determine the potassium flame-photometric method was used. When determining the metrological characteristics of the reference material the Russian national instructions and recommendations MI 3174-2009 and P 50.2.058-2007 were applied. Results. Based on the research findings the reference material of Chinese cabbage composition with a certified value and an expanded uncertainty was developed: for selenium 0.044 ± 0.017 mg/kg; for nitrogen 4.09 ± 0.27 %; for phosphorus 0.69 ± 0.14 %; for potassium 2.87 ± 0.22 %.

  4. 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)

  5. 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.)

  6. 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...

  7. 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.

  8. Effects of soil type, moisture content, redox potential and methyl bromide fumigation on Kd values of radio-selenium in soil

    International Nuclear Information System (INIS)

    Ashworth, D.J.; Moore, J.; Shaw, G.

    2008-01-01

    Understanding the processes that determine the solid-liquid partitioning (K d value) of Se is of fundamental importance in assessing the risk associated with the disposal of radio-selenium-containing waste. Using a mini-column (rather than batch) approach, K d values for 75 Se were determined over time in relation to soil moisture content (field capacity or saturated), redox potential and methyl bromide fumigation (used to disrupt the soil microbial population) in three contrasting soil types: clay loam, organic and sandy loam. The K d values were generally in the range 50-500 L kg -1 , with mean soil K d increasing with increasing organic matter content. Saturation with water lowered the measured redox potentials in the soils. However, only in the sandy loam soil did redox potential become negative, and this led to an increase in 75 Se K d value in this soil. Comparison of the data with the Eh-pH stability diagram for Se suggested that such strong reduction may have been consistent with the formation of the insoluble Se species, selenide. These findings, coupled with the fact that methyl bromide fumigation had no discernible effect on 75 Se K d value in the sandy loam soil, suggest that geochemical, rather than microbial, processes controlled 75 Se partitioning. The inter-relations between soil moisture content, redox potential and Se speciation should be considered in the modelling and assessment of radioactive Se fate and transport in the environment

  9. [FEATURES OF THE CONTENT OF MOVABLE FORMS OF HEAVY METALS AND SELENIUM IN SOILS OF THE YAROSLAVL REGION].

    Science.gov (United States)

    Bakaeva, E A; Eremeyshvili, A V

    2016-01-01

    With the use of the method of inversion voltammetry there was analyzed the content of movableforms of trace elements: (selenium, zinc, copper lead, cadmium) in soils in the Yaroslavl district of the Yaroslavl region, and also content of zinc, copper lead, cadmium in soils and snow cover in the city of Yaroslavl. According to values of concentrations of movable compounds in soils determined trace elements can be ranked into the following row: zinc > lead > copper > selenium > cadmium. There was revealed insufficient if compared with literature data concentrations, content of movable compounds of selenium, copper and zinc in examined explored soils. The maximal concentrations of lead are revealed in the close proximity to both the city of Yaroslavl and large highways of the city. It indicates to the anthropogenic pollution of soils by this element.

  10. 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.)

  11. Selenium and Zinc content and radical scavenging capacity of edible mushrooms Armilaria mellea and Lycoperdon saccatum

    Directory of Open Access Journals (Sweden)

    Z. Zeković

    2010-01-01

    Full Text Available Armillaria mellea and Lycoperdon saccatum are two delicious mushrooms growing widely trough all Balkan region. Investigation of A. mellea and L. saccatum antioxidant properties includes preparation of mushrooms extracts, determination of Selenium and Zinc content and evaluation of theirs antioxidant activity involving scavenging activity of ˙O2- radicals, DPPH and reducing power assay. Higher extraction yield of 24.48 % has been achieved for L. saccatum, but higher content of Selenium and Zinc was determined in A. mallea extract, 2.359 mg/kg and 50.380 mg/kg, respectively. The radical scavenging activity was found to exhibit 50 % of inhibition value (IC50 value at the extracts concentration of 0.0161±0.0001 mg/ml for the L. saccatum extract and 0.0108±0.0002 mg/ml for A. mallea extract. The determined relative inhibition of ˙O2- radicals for L. sacatum extract is lower than for A. malea. It was determined that both mushrooms extract posses’ reductive capabilities and thus were capable of reducing iron (III.

  12. INAA for the evaluation of selenium contents in grain foods consumed by Korean

    International Nuclear Information System (INIS)

    Moon, J.H.; Kim, S.H.; Kim, K.S.; Okhee Lee

    2016-01-01

    This study was aimed to measure the Se content in common consumed grain and potato foods. About 1 g of analytical sample of 40 items of foods was irradiated for 3 h by thermal neutrons (Φ th = 2.8 × 10 13 n/cm 2 s) and 75 Se nuclide was used for the determination of Se contents. The rice showed the range of Se contents from 0.55 to 3.64 μg per 100 g of sample. The Se contents in grain products varied according to the type of grain processing. The acquired Se value in this study will be useful to assess the Se intake of Korean. (author)

  13. Effect of selenium on the Hg, Zn, Fe and Co content of yeast cells

    International Nuclear Information System (INIS)

    Czauderna, M.; Peplowski, A.; Smolinski, S.

    1992-01-01

    The yeast cells, Saccharomyces cerevisiae, were exposed to Hg 2+ ions (10 -4 M) and SeO 2 (2x10 -4 -10 -2 M) or Se-methionine (2x10 -4 M). Instrumental neutron activation analysis (INAA) was used to analyze changes in the Hg, Zn,Fe and Co levels in these cells. When the yeast was incubated in a medium containing 10 -3 M and 10 -2 M Se) 2 , the Hg content of the yeast markedly increased. It was also found that the uptake of Se and Hg influenced the levels of Zn, Fe and Co found in the cells. While the presence of Se-methionine (Se-Met), SeO 2 or Hg 2+ ions caused increases in the intracellular Zn levels, the combined presence of Hg 2+ and SeO 2 and their assumed interaction, reduced the efficiency of Se for increasing the Zn content of yeast. (author) 17 refs.; 3 tabs

  14. [Selenium uptake and transport of rice under different Se-enriched natural soils].

    Science.gov (United States)

    Jiang, Chao-qiang; Shen, Jia; Zu, Chao-long

    2015-03-01

    In this study, a pot experiment was conducted with "Wandao 205" as test materials to investigate Se uptake and translocation in rice under different Se concentrations (0.5, 1.0, and 1.5 mg . kg-1). Results showed that there was no significant change in rice yield when Se concentration in soil was lower than 1.5 mg . kg-1. Significant linear correlations existed between Se concentration in soil and different rice plant tissues. Se concentration in rice plant followed the order of root > straw > grain. Se concentration in different rice grain fractions followed the order of bran > polished rice > hull. The root absorption index of Se was more than 1.86, suggest that the rice could absorpt Se from soil effectively. However, the transport and accumulation of Se in seeds from Se-enriched soil was relatively constant. The Se transport index in seeds was between 0.53 and 0.59. Soil Se concentration within the range of 0.5 to 1.0 mg . kg-1 could produce Se-enriched rice, which might be enough for human requirement of 60-80 µg . d-1 Se. However, polished rice at high-Se treatment (1.5 mg . kg-1) exceeded the maximum standard limit of Se (0.3 mg . kg-1) for cereals in China. These results suggested that we could produce Se-enriched rice under soil Se concentration in the range of 0.5 to 1.0 mg . kg-1 without spraying Se fertilizer, thus reducing the cost and avoiding soil and water pollution caused by exogenous Se.

  15. Selenium biofortification

    Science.gov (United States)

    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...

  16. The Effect of Red Pepper Waste Added to Compost on Selenium Content of Pleurotus citrinopileatus Singer

    Directory of Open Access Journals (Sweden)

    Fatih Kalyoncu

    2016-03-01

    Full Text Available In this study, selenium levels of P.citrinopileatus added different rates of red pepper waste to compost as a source of selenium were determined. For this purpose, six different compost groups were prepared and inoculated with P.citrinopileatus mycelia. Selenium levels of harvested mushrooms were analysed. In conclusion, 0.338 µg/g selenium were determined in one gram dry mushroom that red pepper waste added to compost at 5%. Mycelia growth and selenium accumulation were negatively affected by higher rates of red pepper waste.

  17. Selenium content in the blood serum and urine of ewes receiving selenium-enriched unicellular alga Chlorella

    Czech Academy of Sciences Publication Activity Database

    Trávníček, J.; Písek, I.; Herzig, I.; Doucha, Jiří; Kvíčala, J.; Kroupová, V.; Rodinová, H.

    2007-01-01

    Roč. 52, - (2007), s. 42-48 ISSN 0375-8427 Grant - others:GA ČR(CZ) GD523/03/H076 Program:GD Institutional research plan: CEZ:AV0Z50200510 Source of funding: V - iné verejné zdroje Keywords : sodium selenite * organically bound selenium * ewes Subject RIV: EE - Microbiology, Virology Impact factor: 0.645, year: 2007

  18. 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.

  19. 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...

  20. Role of lattice inhomogeneities on the electronic properties of selenium deficient Bi2Se3

    Science.gov (United States)

    Tayal, Akhil; Kumar, Devendra; Lakhani, Archana

    2017-11-01

    Inter-layer coupling is widely considered to play a crucial role in tuning electronic properties of 3D topological insulators. The aim of this study is to evaluate the role of crystallographic defects on inter-layer coupling in the Se deficient Bi2Se3 (0 0 3) crystal using extended x-ray absorption fine structure spectroscopy (EXAFS) technique. EXAFS measurements at Se-K and Bi-L3 edges reveal distinct local geometry around these atomic sites. It has been observed that short inter-layer Bi-Se and Se-Se bonds emerge in the sample. This additional structural motif coexists with the conventional crystallographic arrangement. Within the quintuple layer Bi-Se bonds are preserved with slight compression in intra-planer Bi-Bi and Se-Se distance and overall reduction in c/a ratio. These findings suggest formation of deformed lattice region, localized and dispersed inhomogeneously within the sample. Such inhomogeneities have also resulted in interesting transport properties such as quantum Hall effect (QHE), large linear magnetoresistance and π-Berry phase in Shubnikov-de Haas (SdH) oscillations of bulk crystals. Detailed analyses of magnetotransport measurements suggest that tuning of inter-layer coupling by local lattice deformation is the key factor for unusual transport properties. Role of axial strain, and stacking faults generated due to defects and charged Se vacancies are discussed to understand the observed electronic properties.

  1. Associations Between Selenium Content in Hair and Kashin-Beck Disease/Keshan Disease in Children in Northwestern China: a Prospective Cohort Study.

    Science.gov (United States)

    Liu, Huan; Yu, Fangfang; Shao, Wanzhen; Ding, Dexiu; Yu, Zhidao; Chen, Fengshi; Geng, Dong; Tan, Xiwang; Lammi, Mikko J; Guo, Xiong

    2018-07-01

    The objective of this study was to investigate the relationship between selenium content in hair and the incidence of Kashin-Beck disease (KBD) and Keshan disease (KD) in China. A prospective cohort study was conducted among children aged 5-12 years with different levels of low-selenium (group 1, Se ≤ 110 ng/g; group 2, 110  200 ng/g) exposure. A person-years approach was used to calculate the incidence and rate of positive clinical signs. Relative risk (RR), attributable risk, and etiologic fraction were used to determine the strength of association between selenium and disease incidence. Seven new KBD cases were diagnosed during 3-year follow-up. Positive clinical signs of KBD were found in 17.78 (95% confidence interval [CI] 14.27-21.29) cases per 100 person-years in group 1, 13.28 (9.82-16.74) in group 2, 12.95 (9.34-16.56) in group 3, and 8.18 (5.50-10.85) in group 4. Compared with group 4, the RR (95% CI) of groups 1, 2, and 3 were 2.17 (1.48-3.19), 1.62 (1.07-2.47), and 1.58 (1.03-2.43), respectively. Positive clinical signs of KD were 25.90 (18.62-33.18) cases per 100 person-years in group 1, 5.66 (1.26-10.06) in group 2, 4.60 (0.20-9.00) in group 3, and 14.62 (8.54-20.69) in group 4. Compared with group 4, the RR (95% CI) were 1.77 (1.07-2.93), 0.39 (0.16-0.93), and 0.31 (0.11-0.89), respectively. In children, the onset of KBD was negatively correlated with selenium content within a certain range. However, there may be a U-shaped association between selenium content and KD in children.

  2. 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)

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

    Science.gov (United States)

    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.

  4. The evolution of the global selenium cycle: Secular trends in Se isotopes and abundances

    Science.gov (United States)

    Stüeken, E. E.; Buick, R.; Bekker, A.; Catling, D.; Foriel, J.; Guy, B. M.; Kah, L. C.; Machel, H. G.; Montañez, I. P.; Poulton, S. W.

    2015-08-01

    The Earth's surface has undergone major transitions in its redox state over the past three billion years, which have affected the mobility and distribution of many elements. Here we use Se isotopic and abundance measurements of marine and non-marine mudrocks to reconstruct the evolution of the biogeochemical Se cycle from ∼3.2 Gyr onwards. The six stable isotopes of Se are predominantly fractionated during redox reactions under suboxic conditions, which makes Se a potentially valuable new tool for identifying intermediate stages from an anoxic to a fully oxygenated world. δ82/78Se shows small fractionations of mostly less than 2‰ throughout Earth's history and all are mass-dependent within error. In the Archean, especially after 2.7 Gyr, we find an isotopic enrichment in marine (+0.37 ± 0.27‰) relative to non-marine samples (-0.28 ± 0.67‰), paired with increasing Se abundances. Student t-tests show that these trends are statistically significant. Although we cannot completely rule out the possibility of volcanic Se addition, these trends may indicate the onset of oxidative weathering on land, followed by non-quantitative reduction of Se oxyanions during fluvial transport. The Paleoproterozoic Great Oxidation Event (GOE) is not reflected in the marine δ82/78Se record. However, we find a major inflection in the secular δ82/78Se trend during the Neoproterozoic, from a Precambrian mean of +0.42 ± 0.45‰ to a Phanerozoic mean of -0.19 ± 0.59‰. This drop probably reflects the oxygenation of the deep ocean at this time, stabilizing Se oxyanions throughout the water column. Since then, reduction of Se oxyanions has likely been restricted to anoxic basins and diagenetic environments in sediments. In light of recent Cr isotope data, it is likely that oxidative weathering before the Neoproterozoic produced Se oxyanions in the intermediate redox state SeIV, whereas the fully oxidized species SeVI became more abundant after the Neoproterozoic rise of

  5. The influence of Se content of the seed and the root of Areca catechu by fermenting of Acetobacter–Saccharomyces consortium as an antimicrobial gargle

    Directory of Open Access Journals (Sweden)

    TITIN YULINERI

    2006-01-01

    Full Text Available The research on the using of Areca catechu seeds and roots extract contain selenium which fermented by Acetobacter–Saccharomyces consortium as a gargle had been conducted. The aim of the research was to know the influence of Se content of the seed and the root of Areca catechu by fermenting of Acetobacter–Saccharomyces consortium on the growth of Streptococcus mutans bacteria. The research consisted of four stages i.e. fermented the extract, isolated S. mutans, tested the activity of the antimicrobial and analyzed selenium concentration in the extract. The result showed that the concentration of selenium has fluctuation. The highest content of selenium of the seeds extract at 2.2 g/L concentration was 3.05 ppb on the fifteenth day while on the root extract at 8.8 g/L was 14.03 ppb on the twenty first day fermentation. Both of the extract has potential used as antiseptic gargle. The antimicrobial agents could inhibit the growth of S. mutans better than the three kinds of commercial gargles.

  6. Effect of selenium treatment on biomass production and mineral content in common bean varieties

    Science.gov (United States)

    The mineral selenium is important to human health. The goal of the research was to evaluate common bean cultivars for their responses to and abilities to accumulate selenium. The experimental design was completely randomized and the treatments consisted of control (in modified Hoagland and Arnon's s...

  7. Electrical Properties Of Amorphous Selenium (aSe)/p-Type Silicon ...

    African Journals Online (AJOL)

    aSe) on four chemically etched p-type silicon crystals (pSi) each of 5Ω-cm resistivity and carrier concentration of 2.8x1015cm-3. Two of the pSi crystals have surface orientation of (111) while the other two crystals have (100) surface orientation.

  8. 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...

  9. 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.

  10. 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.

  11. Selenium-induced toxicity is counteracted by sulfur in broccoli (Brassica oleracea L. var. italic)

    Science.gov (United States)

    Selenium (Se) is an essential micronutrient for humans. Increasing Se content in food crops offers an effective approach to enhance the consumption of Se in human diets. A thoroughly understanding of the effects of Se on plant growth is important for Se biofortification in food crops. Given that Se ...

  12. Selenium content in milk and diary samples; Conteudo de selenio em amostras de leite, queijos e achocolatados

    Energy Technology Data Exchange (ETDEWEB)

    Kira, Carmen S. [Instituto Adolfo Lutz, Sao Paulo, SP (Brazil). Secao de Equipamentos Especializados. Div. de BQ]. E-mail: carmkira@ial.sp.gov.br; Maihara, Vera A. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil). Lab. de Analise por Ativacao Neutronica]. E-mail: vmaihara@ipen.br

    2005-07-01

    Food is the primary source of Se for human beings. As such determining Se levels in foodstuffs become very important. However, information concerning Se levels in different sources of nutrition in different country, particularly in Brazil, is limited. Instrumental Neutron Activation Analysis (INAA) has been used to effectively determine micronutrient levels in foodstuffs, such as milk and dairy samples. The advantage of using the INAA technique is that the samples do not require previous dissolution before analysis. In this study, INAA was applied to determine Se concentration in milk and dairy products. The samples were acquired in the markets of Sao Paulo city. After a 8-hour irradiation in the research reactor IEA-R1, selenium was analyzed by gamma-ray spectrometry. Methodology validation was done analyzing NIST reference materials (Whole Milk Powder and Non Fat Milk Powder). Se concentrations in the sample analyzed were below 0.300 {mu}g g{sup -1}. (author)

  13. 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.

  14. 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...

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

    Directory of Open Access Journals (Sweden)

    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

  16. 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)

  17. 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)

  18. 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...

  19. 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

  20. 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.

  1. 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)

  2. 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.

  3. Selenium Biofortification in Fragaria × ananassa: Implications on Strawberry Fruits Quality, Content of Bioactive Health Beneficial Compounds and Metabolomic Profile

    Directory of Open Access Journals (Sweden)

    Tanja Mimmo

    2017-11-01

    Full Text Available Selenium (Se is an essential nutrient for humans, due to its antioxidant properties, whereas, to date, its essentiality to plants still remains to be demonstrated. Nevertheless, if added to the cultivation substrate, plants growth resulted enhanced. However, the concentration of Se in agricultural soils is very variable, ranging from 0.01 mg kg-1 up to 10 mg kg-1 in seleniferous areas. Therefore several studies have been performed aimed at bio-fortifying crops with Se and the approaches exploited were mainly based on the application of Se fertilizers. The aim of the present research was to assess the biofortification potential of Se in hydroponically grown strawberry fruits and its effects on qualitative parameters and nutraceutical compounds. The supplementation with Se did not negatively affect the growth and the yield of strawberries, and induced an accumulation of Se in fruits. Furthermore, the metabolomic analyses highlighted an increase in flavonoid and polyphenol compounds, which contributes to the organoleptic features and antioxidant capacity of fruits; in addition, an increase in the fruits sweetness also was detected in biofortified strawberries. In conclusion, based on our observations, strawberry plants seem a good target for Se biofortification, thus allowing the increase in the human intake of this essential micronutrient.

  4. A pilot study of the selenium content in the soils of the endemic Dobrogea region, Romania, using nuclear and related analytical techniques

    International Nuclear Information System (INIS)

    Tripadus, V.; Craciun, L.; Lacatusu, R.; Frontasyeva, M.V.; Stan, O.; Lyapunov, S.M.

    2000-01-01

    At present, there is growing interest in the understanding of the role of selenium in human and animal metabolism. Selenium is known to be a normal component of several enzymes, proteins and some aminoacrylic transfer nucleic acids. Low levels of selenium intake are reported to cause diseases such as cardiomyopathy (Keshan disease), cancer and endemic osteoarthropathy characterized by necrosis of cartilage and dystrophy of skeletal muscles (Kaschin-Beck disease). In conjunction with the vitamin E, it removes free radicals from the living organisms. About two-to-three orders of magnitude higher levels of selenium are known to impart toxic effects. The Dobrogea Region in Romania is known for endemic cardiovascular diseases affecting domestic cattle, mostly sheep and milk cows. Soil, being the source of selenium, is responsible for its content in the whole trophic chain. A limited number of soil samples collected in the pastures (Dobrogea) were subject to epithermal neutron activation analysis at the IBR-2 pulsed fast reactor in Dubna, Russia. To verify the obtained results, the same samples were analyzed by the fluorescent extraction method, especially efficient for determination of selenium at low concentrations, at the Geological Institute of RAS in Moscow, Russia. The mean concentration of selenium was found to be equal to 0.38 ppm with a standard deviation of 0.13. The accuracy of the selenium determination was not worse than 20%. These preliminary results are not evidence of obvious selenium deficiency, however. A systematic study on a large geographical scale is strongly recommended to elucidate the problem of cattle morbidity in the examined area. (authors)

  5. 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.

  6. 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.

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

    Science.gov (United States)

    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.

  8. 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.

  9. Cancer incidence following long-term consumption of drinking water with high inorganic selenium content.

    Science.gov (United States)

    Vinceti, Marco; Vicentini, Massimo; Wise, Lauren A; Sacchettini, Claudio; Malagoli, Carlotta; Ballotari, Paola; Filippini, Tommaso; Malavolti, Marcella; Rossi, Paolo Giorgi

    2018-04-16

    Selenium, a trace element to which humans are exposed mainly through diet, has been involved in the etiology of human cancer. We investigated the long-term effects of selenium exposure on cancer incidence using data from a natural experiment in Northern Italy. During the 1970s-1980s, in a part of the Italian municipality of Reggio Emilia, residents were inadvertently exposed to unusually high levels of inorganic hexavalent selenium (selenate) through drinking water. We followed the exposed residents for 28years, generating data on incidence (when available) and mortality rates for selected cancer sites; the remaining municipal residents comprised the unexposed (reference) group. We observed no substantial difference in overall cancer incidence comparing exposed and unexposed cohorts. We detected, however, a higher incidence of cancer at some sites, and for a few of them, namely cancers of the buccal cavity and pharynx, melanoma, urinary tract and lymphoid tissue, the excess incidence was particularly evident in the first period of follow-up but decreased over time. Overall, these results suggest that consumption of water with levels of selenium in its inorganic hexavalent form close to the European standard, 10μg/L, may have unfavourable effects on cancer incidence. Copyright © 2018 Elsevier B.V. All rights reserved.

  10. 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.

  11. Dynamic equilibrium of endogenous selenium nanoparticles in selenite-exposed cancer cells: a deep insight into the interaction between endogenous SeNPs and proteins.

    Science.gov (United States)

    Bao, Peng; Chen, Song-Can; Xiao, Ke-Qing

    2015-12-01

    Elemental selenium (Se) was recently found to exist as endogenous nanoparticles (i.e., SeNPs) in selenite-exposed cancer cells. By sequestrating critical intracellular proteins, SeNPs appear capable of giving rise to multiple cytotoxicity mechanisms including inhibition of glycolysis, glycolysis-dependent mitochondrial dysfunction, microtubule depolymerization and inhibition of autophagy. In this work, we reveal a dynamic equilibrium of endogenous SeNP assembly and disassembly in selenite-exposed H157 cells. Endogenous SeNPs are observed both in the cytoplasm and in organelles. There is an increase in endogenous SeNPs between 24 h and 36 h, and a decrease between 36 h and 72 h according to transmission electron microscopy results and UV-Vis measurements. These observations imply that elemental Se in SeNPs could be oxidized back into selenite by scavenging superoxide radicals and ultimately re-reduced into selenide; then the assembly and disassembly of SeNPs proceed simultaneously with the sequestration and release of SeNP high-affinity proteins. There is also a possibility that the reduction of elemental Se to selenide pathway may lie in selenite-exposed cancer cells, which results in the assembly and disassembly of endogenous SeNPs. Genome-wide expression analysis results show that endogenous SeNPs significantly altered the expression of 504 genes, compared to the control. The endogenous SeNPs induced mitochondrial impairment and decreasing of the annexin A2 level can lead to inhibition of cancer cell invasion and migration. This dynamic flux of endogenous SeNPs amplifies their cytotoxic potential in cancer cells, thus provide a starting point to design more efficient intracellular self-assembling systems for overcoming multidrug resistance.

  12. 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.

  13. Antioxidant capacity of meagre (Argyrossomus regius fed different lipid content and source, with and without selenium

    Directory of Open Access Journals (Sweden)

    Sthelio Braga Fonseca

    2014-06-01

    Meagre (600 animals were kept in 24 tanks (80 L with constant renovation and aeration and maintained at 20.7 ± 0.7ºC and oxygen 8.8 ± 1.7 mg L-1. Fish were fed twice per day, six days per week, with eight different experimental diets for 60 days. Diets were formulated to have two different oil sources (fish or vegetable blend oils with 45% of linseed, 35% of rapeseed and 20% of soybean oil, two lipid levels (12 and 17% and two selenium supplementation (0 and 1 mg/kg diet. Lipid peroxidation (LPO, glutathione reductase (GR, glutathione peroxidase (GPx, total glutathione (TG and catalase (CAT were analyzed in liver of fish. CAT, GPx and GR activities were not significantly altered in fish fed with diets with different oil sources. However, TG in fish fed with fish oil diet was higher than the levels observed in fish fed with vegetable blend oil. Furthermore, fish fed with fish oil diet showed lower lipid peroxidation when compared with fish fed vegetable blend oil diet (Table 1. Concerning the oil level in diet, it was observed that fish fed with a diet of 17% lipids had a higher level of total glutathione when compared to fish fed with a diet of 12% lipids. On the other hand, the fish fed with a diet with 12% lipids showed lower levels of lipid peroxidation when compared to fish fed with a diet of 17% lipids. Fish fed with diets supplemented with selenium showed a significantly increased activity of GPx when compared with fish fed without selenium. Three-way ANOVA analysis showed that dietary lipid level and the presence of selenium have a significant interaction on the activities of CAT and GR, as well as, levels of TG and LPO. A significant interaction between the source of oil and the presence of selenium on GR activities was observed. Interaction on source and level was observed to CAT. In conclusion, the antioxidant capacity of meagre is influenced by the source of oil, the level of lipids and the presence of selenium in their diet.

  14. 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.)

  15. 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

  16. 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)

  17. Liquid chromatography-electrospray ionization tandem mass spectrometry for on-line characterization, monitoring and isotopic profiling of the main selenium-metabolite in human urine after consumption of Se-rich and Se-enriched food

    International Nuclear Information System (INIS)

    Dumont, Emmie; Ogra, Yasumitsu; Suzuki, Kazuo T.; Vanhaecke, Frank; Cornelis, Rita

    2006-01-01

    The metabolism of selenium (Se) in the human body has yet not completely been unravelled and hence, an efficient method for characterization and on-line monitoring of the main Se-compound in human urine after consumption of Se-rich food was developed. Total Se-concentration in human urine after consumption of several Se-rich products was measured with inductively coupled plasma mass spectrometry (ICP-MS). The highest Se concentration in urine was observed after 4-10 h. The urine samples were brought onto a reversed phase column and the Se was detected by ICP-MS. Parameters for liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS-MS) measurements were optimized by using commercially available sugars, because it is known that some of the urinary metabolites contain a sugar moiety. In order to characterize the predominant Se-metabolite, it was necessary to extensively clean-up the sample and preconcentrate the species. The main metabolite was measured on its precursor ion on three different m/z according to three isotopes of Se. Relative peak surfaces matched the relative abundances of the isotopes. The product ions could be measured in a human urine sample in accordance to the product ions of the commercially available sugars. Moreover, the evidence of a selenosugar was demonstrated by the use of the Se-isotopes when measuring the product ions. LC-ESI-MS-MS was proven to be very efficient for the characterization of the main urinary Se-metabolite and can be used for on-line monitoring of the compound in urine samples. The method can be extended for clinical screening after consumption of Se-(en)rich(ed) food by use of the Se-isotopic profile and/or of the typical product ions of (methyl)-N-acetyl-hexosamines

  18. 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

  19. Selenium-assisted controlled growth of graphene–Bi_2Se_3 nanoplates hybrid Dirac materials by chemical vapor deposition

    International Nuclear Information System (INIS)

    Sun, Zhencui; Man, Baoyuan; Yang, Cheng; Liu, Mei; Jiang, Shouzhen; Zhang, Chao; Zhang, Jiaxin; Liu, Fuyan; Xu, Yuanyuan

    2016-01-01

    Graphical abstract: - Highlights: • We synthesize the graphene–Bi_2Se_3 nanoplates hybrid Dirac materials via CVD. • The Se seed layer impels the Bi_2Se_3 plates growing along the lateral direction. • The Se seed layer can supply enough Se atoms to fill the Se vacancies. • The Se seed layer can effectively avoid the interaction of Bi_2Se_3 and the graphene. • The Se seed layer can be used to control the density of the Bi_2Se_3 nanoplates. - Abstract: Se seed layers were used to synthesize the high-quality graphene–Bi_2Se_3 nanoplates hybrid Dirac materials via chemical vapor deposition (CVD) method. The morphology, crystallization and structural properties of the hybrid Dirac materials were characterized by SEM, EDS, Raman, XRD, AFM and HRTEM. The measurement results verify that the Se seed layer on the graphene surface can effectively saturate the surface dangling bonds of the graphene, which not only impel the uniform Bi_2Se_3 nanoplates growing along the horizontal direction but also can supply enough Se atoms to fill the Se vacancies. We also demonstrate the Se seed layer can effectively avoid the interaction of Bi_2Se_3 and the graphene. Further experiments testify the different Se seed layer on the graphene surface can be used to control the density of the Bi_2Se_3 nanoplates.

  20. Understanding the paradox of selenium contamination in mercury mining areas: high soil content and low accumulation in rice.

    Science.gov (United States)

    Zhang, Hua; Feng, Xinbin; Jiang, Chengxin; Li, Qiuhua; Liu, Yi; Gu, Chunhao; Shang, Lihai; Li, Ping; Lin, Yan; Larssen, Thorjørn

    2014-05-01

    Rice is an important source of Se for billions of people throughout the world. The Wanshan area can be categorized as a seleniferous region due to its high soil Se content, but the Se content in the rice in Wanshan is much lower than that from typical seleniferous regions with an equivalent soil Se level. To investigate why the Se bioaccumulation in Wanshan is low, we measured the soil Se speciation using a sequential partial dissolution technique. The results demonstrated that the bioavailable species only accounted for a small proportion of the total Se in the soils from Wanshan, a much lower quantity than that found in the seleniferous regions. The potential mechanisms may be associated with the existence of Hg contamination, which is likely related to the formation of an inert Hg-Se insoluble precipitate in soils in Wanshan. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Selenium Sulfide

    Science.gov (United States)

    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 ...

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

    Science.gov (United States)

    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.

  3. Determination of selenium in biological material by instrumental neutron activation analysis using {sup 77m} Se radioisotope; Determinacao de selenio em materiais biologicos por analise por ativacao com neutrons instrumental usando o radioisotopo {sup 77m} Se

    Energy Technology Data Exchange (ETDEWEB)

    Vasconcellos, Maria B.A.; Moreira, Edson G.; Catharino, Marilia G.M.; Tokura, Alexandra M.; Saiki, Mitiko [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil). Supervisao de Radioquimica

    1999-11-01

    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 {sup 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) 5 refs., 7 tabs.

  4. 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.)

  5. 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.

  6. Biofortification (Se: Does it increase the content of phenolic compounds in virgin olive oil (VOO?

    Directory of Open Access Journals (Sweden)

    Roberto D'Amato

    Full Text Available Extra-Virgin Olive Oil (EVOO is a fundamental component of the Mediterranean diet and it may contain several anti-oxidant substances, such as phenols. Previous research has shown that this food may be enriched in phenols by spraying a sodium-selenate solution (100 mg L-1 Se onto the crop canopy before flowering. The aim of this research was to evaluate the effect of this Se-fertilization before flowering (cv. Leccino on the phenolic profile of EVOOs, and test to what extent such effects depend on the weather pattern, as observed in two contrasting experimental seasons (2013 and 2014. Results showed that Se-fertilisation enriched EVOOs both in selenium (up to 120 μg kg-1 and in phenols (up to 401 mg kg-1. This latter enrichment was related to an increase in PAL (L-Phenylalanine Ammonia-Lyase activities and it was largely independent on the climatic pattern. Considering the phenolic profile, oleacein, ligustroside, aglycone and oleocanthal were the most affected compounds and were increased by 57, 50 and 32%, respectively. All these compounds, especially oleacein, have been shown to exert a relevant anti-oxidant activity, contributing both to the shelf-life of EVOOs and to positive effects on human health. It is suggested that Se-fertilisation of olive trees before flowering may be an interesting practice, particularly with poor cultivars and cold and rainy weather patterns, which would normally lead to the production of EVOOs with unfavourable phenolic profile.

  7. Biofortification (Se): Does it increase the content of phenolic compounds in virgin olive oil (VOO)?

    Science.gov (United States)

    D’Amato, Roberto; Proietti, Primo; Onofri, Andrea; Regni, Luca; Esposto, Sonia; Servili, Maurizio; Businelli, Daniela; Selvaggini, Roberto

    2017-01-01

    Extra-Virgin Olive Oil (EVOO) is a fundamental component of the Mediterranean diet and it may contain several anti-oxidant substances, such as phenols. Previous research has shown that this food may be enriched in phenols by spraying a sodium-selenate solution (100 mg L-1 Se) onto the crop canopy before flowering. The aim of this research was to evaluate the effect of this Se-fertilization before flowering (cv. Leccino) on the phenolic profile of EVOOs, and test to what extent such effects depend on the weather pattern, as observed in two contrasting experimental seasons (2013 and 2014). Results showed that Se-fertilisation enriched EVOOs both in selenium (up to 120 μg kg-1) and in phenols (up to 401 mg kg-1). This latter enrichment was related to an increase in PAL (L-Phenylalanine Ammonia-Lyase) activities and it was largely independent on the climatic pattern. Considering the phenolic profile, oleacein, ligustroside, aglycone and oleocanthal were the most affected compounds and were increased by 57, 50 and 32%, respectively. All these compounds, especially oleacein, have been shown to exert a relevant anti-oxidant activity, contributing both to the shelf-life of EVOOs and to positive effects on human health. It is suggested that Se-fertilisation of olive trees before flowering may be an interesting practice, particularly with poor cultivars and cold and rainy weather patterns, which would normally lead to the production of EVOOs with unfavourable phenolic profile. PMID:28448631

  8. 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.

  9. Zr{sub 2}N{sub 2}Se. The first zirconium(IV) nitride selenide by the oxidation of zirconium(III) nitride with selenium

    Energy Technology Data Exchange (ETDEWEB)

    Lissner, Falk; Hack, Bettina; Schleid, Thomas [Institute for Inorganic Chemistry, University of Stuttgart (Germany); Lerch, Martin [Institute for Chemistry, Technical University of Berlin (Germany)

    2012-08-15

    The oxidation of zirconium(III) nitride (ZrN) with suitable amounts of selenium (Se) in the presence of sodium chloride (NaCl) as flux yields small yellow brownish platelets of the first zirconium(IV) nitride selenide with the composition Zr{sub 2}N{sub 2}Se. The new compound crystallizes in the hexagonal space group P6{sub 3}/mmc (no. 194) with a = 363.98(2) pm, c = 1316.41(9) pm (c/a = 3.617) and two formula units per unit cell. The crystallographically unique Zr{sup 4+} cations are surrounded by three selenide and four nitride anions in the shape of a capped trigonal antiprism. The Se{sup 2-} anions are coordinated by six Zr{sup 4+} cations as trigonal prism and the N{sup 3-} anions reside in tetrahedral surrounding of Zr{sup 4+} cations. These [NZr{sub 4}]{sup 13+} tetrahedra become interconnected via three edges each to form {sup 2}{sub ∞}{[(NZr_4_/_4)_2]"2"+} double layers parallel to the (001) plane, which are held together by monolayers of Se{sup 2-} anions. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  10. SELENIUM ACCUMULATION BY BASIL PLANTS (OCINUM BASILICUM L.

    Directory of Open Access Journals (Sweden)

    N. A. Golubkina

    2014-01-01

    Full Text Available Selenium accumulation level in basil plants is investigated. A direct correlation between selenium concentration and essential oil content is demonstrated for basil and other aroma plants. No correlation is found between selenium and flavonoids.

  11. 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

  12. Effects of selenium biofortification on crop nutritional quality

    Directory of Open Access Journals (Sweden)

    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.

  13. Biomarkers of selenium status

    Science.gov (United States)

    The essential trace element selenium (Se) has multiple biological activities, which depend on the level of Se intake. Relatively low Se intakes determine the expression of selenoenzymes in which it serves as an essential constituent. Higher intakes have been shown to have anti-tumorigenic potentia...

  14. Pancreas Scanning with Se{sup 75}-Selenomethionine; Scintigraphie du Pancreas avec de la Selenomethionine Marquee au Selenium-75; Skennirovanie podzheludochnoj zhelezy s pomoshch'yu selenometionina, mechennogo Selenom-75; Exploracion del Pancreas con Selenometionina-{sup 75}Se

    Energy Technology Data Exchange (ETDEWEB)

    Blau, M. [Department of Nuclear Medicine, Roswell Park Memorial Institute, Buffalo, NY (United States)

    1964-10-15

    Amino-acids show a high degree of localization in the pancreas during the first few hours after administration. This specificity is related to the rapid synthesis and turnover of the digestive enzymes. Since none of the elements in the structure of amino-acids (C,H, N,0 and S) have suitable gamma-emitting isotopes, they cannot be used for scanning. Several I{sup 131} derivatives of amino-acids were prepared and tested, but the pancreas-localizing property of the original amino-acid was lost in every case. The chemical similarity of selenium and sulphur suggested that the selenium analogue of methionine might resemble methionine closely enough to take its place in protein synthesis. Se{sup 75} (halflife, 128 d; principal gamma-ray, 0.27 MeV) is suitable for scanning. Selenium-75-selenomethionine was prepared by yeast biosynthesis. The yeast was grown on a low sulphur medium containing high specific activity Se{sup 75} as selenite. After extraction with ether and hot trichloracetic acid, the protein residue was hydrolysed with hydrochloric acid The resulting amino-acid mixture was separated by column chromatography. Selenium-75-selenomethionine prepared in this manner showed biological properties of a natural aminoacid. The uptake in pancreas was about 7% of the administered dose and the concentration in a gramme of pancreas was seven times that in a gramme of liver. Blood and other organs had even lower uptakes. The clinical usefulness of pancreas scanning is now being evaluated. Tumours of the pancreas have been found as areas of decreased uptake. There is no concentration of selenomethionine in cases of acute pancreatitis. It is too early to give a statistical estimate of our ability to find tumours of the pancreas by this technique. The estimated total body dose from this procedure is less than 1 rad. The selenium dose is only a. few microgrammes and represents no toxicity hazard. (author) [Spanish] Los aminoacidos tienden a localizarse en el pancreas durante las

  15. 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.)

  16. 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.

  17. 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

  18. 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.

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

    Directory of Open Access Journals (Sweden)

    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.

  20. 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.

  1. 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.

  2. 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.

  3. Migration of {sup 75}Se(IV) in crushed Beishan granite: Effects of the iron content

    Energy Technology Data Exchange (ETDEWEB)

    He, Jiangang; Ma, Bin; Kang, Mingliang; Wang, Chunli; Nie, Zhe; Liu, Chunli, E-mail: liucl@pku.edu.cn

    2017-02-15

    Highlights: • The diffusion of {sup 75}SeO{sub 3}{sup 2−} in crushed BsG was slowest at approximately pH 5. • The D{sub a} values under aerobic conditions were nearly one order of magnitude lower than those under anaerobic conditions. • Fe(II)-bearing mineralogical components can be responsible for the great difference in D{sub a} values. • Se{sup IV} can be reduced to Se{sup 0} by BsG under anaerobic conditions. - Abstract: The diffusion of selenite (labeled with {sup 75}Se) in compacted Beishan granite (BsG) was investigated using the in-diffusion capillary method at pH values from ∼2.0 to ∼11.0 under oxic and anoxic conditions. The results indicate that the apparent diffusion coefficient (D{sub a}) values of selenite in BsG always reached the minimum at approximately pH 5. Unexpectedly, the D{sub a} values under oxic conditions are nearly one order of magnitude lower than those under the anoxic conditions. Further characterization reveals the existence of redox-sensitive Fe(II)-containing components, which can be responsible for the great difference in D{sub a} values. Fe(2p) X-ray photoelectron spectroscopy (XPS) results show that more Fe(III)-oxyhydroxide coating is formed on the granite’s surface under aerobic conditions than is formed under anaerobic conditions. Correspondingly, Se(3d) spectra indicate that more selenium is sorbed under oxic conditions, and the sorbed amount always reached the maximum at pH values from ∼4 to ∼5. A linear combination fit of X-ray absorption near edge structure (XANES) spectroscopy data revealed that Se(0) was formed under anoxic condition and that selenite preferred to form inner-sphere complexes with Fe(III)-oxyhydroxide. Overall, this study indicates that natural Fe-bearing minerals can greatly attenuate selenite diffusion and the retardation would be enhanced under aerobic conditions.

  4. 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.

  5. 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, ...

  6. 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.

  7. Columnar recombination for X-ray generated electron-holes in amorphous selenium and its significance in a-Se x-ray detectors

    International Nuclear Information System (INIS)

    Bubon, O.; Jandieri, K.; Baranovskii, S. D.; Kasap, S. O.; Reznik, A.

    2016-01-01

    Although amorphous selenium (a-Se) has a long and successful history of application in optical and X-ray imaging, some of its fundamental properties are still puzzling. In particularly, the mechanism of carrier recombination following x-ray excitation and electric field and temperature dependences of the electron-hole pair creation energy (W_e_h_p) remain unclear. Using the combination of X-ray photocurrent and pulse height spectroscopy measurements, we measure W_e_h_p in a wide range of temperatures (218–320 K) and electric fields (10–100 V/µm) and show that the conventional columnar recombination model which assumes Langevin recombination within a column (a primary electron track) fails to explain experimental results in a wide range of electric fields and temperatures. The reason for the failure of the conventional model is revealed in this work, and the theory of the columnar recombination is modified to include the saturation of the recombination rate at high electric field in order to account for the experimental results in the entire range of fields and temperatures.

  8. 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...

  9. Selenium Accumulation in Unicellular Green Alga Chlorella vulgaris and Its Effects on Antioxidant Enzymes and Content of Photosynthetic Pigments

    Science.gov (United States)

    Sun, Xian; Zhong, Yu; Huang, Zhi; Yang, Yufeng

    2014-01-01

    The aim of the present study was to investigate selenite effects in the unicellular green algae Chlorella vulgaris as a primary producer and the relationship with intracellular bioaccumulation. The effects of selenite were evaluated by measuring the effect of different selenite concentrations on algal growth during a 144 h exposure period. It was found that lower Se concentrations (≤75 mg L−1) positively promoted C. vulgaris growth and acted as antioxidant by inhibiting lipid peroxidation (LPO) and intracellular reactive oxygen species (ROS). The antioxidative effect was associated with an increase in guaiacol peroxidase (GPX), catalase (CAT), superoxide dismutase (SOD) and photosynthetic pigments. Meanwhile, significant increase in the cell growth rate and organic Se content was also detected in the algae. In contrast, these changes were opposite in C. vulgaris exposed to Se higher than 100 mg L−1. The antioxidation and toxicity appeared to be correlated to Se bioaccumulation, which suggests the appropriate concentration of Se in the media accumulation of C. vulgaris should be 75 mg L−1. Taken together, C. vulgaris possesses tolerance to Se, and Se-Chlorella could be developed as antioxidative food for aquaculture and human health. PMID:25375113

  10. Review on Nano SeleniumProduced by Bacteria

    Directory of Open Access Journals (Sweden)

    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.

  11. Combustion characteristics and retention-emission of selenium during co-firing of torrefied biomass and its blends with high ash coal.

    Science.gov (United States)

    Ullah, Habib; Liu, Guijian; Yousaf, Balal; Ali, Muhammad Ubaid; Abbas, Qumber; Zhou, Chuncai

    2017-12-01

    The combustion characteristics, kinetic analysis and selenium retention-emission behavior during co-combustion of high ash coal (HAC) with pine wood (PW) biomass and torrefied pine wood (TPW) were investigated through a combination of thermogravimetric analysis (TGA) and laboratory-based circulating fluidized bed combustion experiment. Improved ignition behavior and thermal reactivity of HAC were observed through the addition of a suitable proportion of biomass and torrefied. During combustion of blends, higher values of relative enrichment factors in fly ash revealed the maximum content of condensing volatile selenium on fly ash particles, and depleted level in bottom ash. Selenium emission in blends decreased by the increasing ratio of both PW and TPW. Higher reductions in the total Se volatilization were found for HAC/TPW than individual HAC sample, recommending that TPW have the best potential of selenium retention. The interaction amongst selenium and fly ash particles may cause the retention of selenium. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. SELENIUM SUBSTITUTION – EFFECT ON THYROID FUNCTION

    Directory of Open Access Journals (Sweden)

    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.

  13. 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.

  14. 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...

  15. 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...

  16. Studies on the relationship between trace element (selenium, zinc) accumulation in hair and metabolism in body of rabbit by using 75Se and 65Zn tracer technique

    International Nuclear Information System (INIS)

    Cai Xuelin; Song Xuehua; Wu Suqiong

    1999-01-01

    In the study, the rabbit was used as experimental animal. After 2 months of feeding the diet with different levels of Se or Zn, five animals from each group were given an oral dose of Na 2 75 SeO 3 or 65 ZnSO 4 solution, respectively. The process of absorption, exertion, accumulation and transfer of isotopes to the hair were determined, and the tissues retention of 75 Se or 65 Zn were also examined at the end of the experiments. The results obtained from the measurement of radioactive change of back hair in each group animal after the oral intake of 75 Se or 65 Zn showed that the 75 Se or 65 Zn transfer to hair were fast. At the seventh and fifth day after dosing, the 75 Se or 65 Zn were determined in the down-end section and upper-end section of back hair, and the radioactivity increased with time. At the first, the radioactivity in down-end section was higher than that of the upper-end section. However, at the end of experiment the upper-end section was higher than the down-end section. The data obtained from the different measuring point indicated that the accumulation, distribution of trace element in hair was not even. there was extended process from the down-end to the upper-end of hair and accumulation in upper-end section. The content of 75 Se or 65 Zn in hair was related to the level of Se or Zn in diet. However, there were difference among the different trace elements

  17. 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

  18. Selenium essentials

    CERN Document Server

    Sams, Prashanth

    2015-01-01

    If you are a developer who wants to migrate from Selenium RC or any other automation tool to Selenium WebDriver, then this book is for you. Knowledge of automation tools is necessary to follow the examples in this book.

  19. Selenium balance in the adult cat in relation to intake of dietary sodium selenite and organically bound selenium

    NARCIS (Netherlands)

    Todd, S.E.; Thomas, D.G.; Hendriks, W.H.

    2012-01-01

    The response of cats to dietary sodium selenite (Na2SeO3) and organically bound selenium was studied in two separate studies with four cats per treatment and three levels of selenium supplementation (targets 1.0, 1.5 and 2.0 µg/g DM) for each Se source. Whole blood and plasma selenium concentrations

  20. The relationship between selenium and gastric cancer

    International Nuclear Information System (INIS)

    Shi Kuixiong; Ma Guansheng; Zhang Tingyu; Cheng Wufeng; Mao Dajuan; Pan Bixia; Xu Xiuxian

    1993-01-01

    Both sodium selenite and selenium yeast were chosen to block the MNNG mutagenesis. The inhibition rates were 66.5% and 37.9% respectively. The selenium levels in hair, serum and gastric juice, and the contents of nitrosamine in gastric juice were also determined. The results showed that the selenium levels were SG > CAG and Dys > GC (p CAG, Dyas and GC (p < 0.05). 19 cases of CAG patients treated with selenium yeast and 16 cases of the control were observed. After 10 weeks, the selenium levels in serum for the treated group were significantly increased. The symptoms of CAG patients seemed to be alleviated

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

    Science.gov (United States)

    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.

  2. 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.

  3. 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

  4. Selenium speciation profiles in biofortified sangiovese wine.

    Science.gov (United States)

    Fontanella, Maria Chiara; D'Amato, Roberto; Regni, Luca; Proietti, Primo; Beone, Gian Maria; Businelli, Daniela

    2017-09-01

    Biofortification is an agronomic-based strategy, utilized by farmers, to produce selenium (Se)-enriched food products that may help reduce dietary deficiencies of Se occurring throughout susceptible regions of the world. The foliar exposure route application ensures a high efficiency of Se assimilation by the plant since it does not depend on root-to-shoot translocation. In this study we treated grapevines of Sangiovese variety in the pre-flowering period with sodium selenate (100mg Se L -1 ). Se content was measured in leaves, fruit at harvest time and in wine respectively in treated and not treated samples with ICP-MS. At harvest, a higher amount of Se in the treated leaves compared to untreated ones was found, 16.0±3.1mgkg -1 dry weight (dw) against 0.17±0.006mgkg -1 dw in the untreated ones. The treated grapes had a content of Se of 0.800±0.08mgkg -1 dw, while that untreated one 0.065±0.025mgkg -1 dw. Immediately after the malolactic fermentation, the wine obtained from treated and untreated vines had a Se content of 0.620±0.09mg Se L -1 and 0.024±0.010mg Se L -1 respectively. In our case the percentage of inorganic Se is 26% of the total Se in the untreated wine, while in Se enriched wine this percentage increase to 47.5% of the total Se. The Se(VI) was the inorganic chemical form more present in enriched wine, probably due to foliar application with selenate. Distributions of Se species suggested being careful to the choice of the enrichment solutions to promote a balanced distribution of different chemical forms, perhaps favouring the accumulation of organic forms. Copyright © 2016 Elsevier GmbH. All rights reserved.

  5. Determination of molybdenum and selenium in bioenvironmental samples using neutron activation analysis

    International Nuclear Information System (INIS)

    Abu-Samra, A.; Morris, J.S.; Koirtyohann, S.R.; Vogt, J.R.

    1974-01-01

    Because of the increasing interest as to their roles in biological systems, a procedure has been developed by which molybdenum and selenium can be determined at nanogram levels in these types of samples. Results from the analysis of orchard leaves and bovine liver are presented. The samples are packaged in pre-cleaned quartz vials prepared from GE-204 tubing. If both selenium and molybdenum are to be determined, the samples are irradiated for 40 or more hours at a thermal neutron flux of 8 x 10 13 n cm -2 sec -1 . After the samples have decayed for approximately 48 hours the vials are unpackaged, cleaned in aqua-regia, and broken. The irradiation period can be reduced to 24 hours if molybdenum is to be determined individually or if the selenium content is known to be 1 microgram or more. The sample is digested with carriers and the selenium is then distilled as a volatile selenium halide. Elemental selenium is precipitated by reduction with SO 2 produced through the protonation of the hydrogen sulfite ion and subsequent decomposition of the resulting sulfurous acid. The 401 keV summation peak of 75 Se is normally used for quantitative determination. The chemical yield is determined by drying and weighing the elemental selenium

  6. The correlation between selenium adsorption and the mineral and chemical composition of Taiwan local granite samples

    Energy Technology Data Exchange (ETDEWEB)

    Wang, TsingHai; Chiang, Chu-Ling; Wang, Chu-Fang [National Tsing Hua Univ., Hsinchu, Taiwan (China). Biomedical Engineering and Environmental Sciences

    2015-07-01

    Selenium-79 (Se-79) is a radioactive isotope of selenium, which is considered as one of the highly mobile nuclides since Se-79 would be presented in an anion species when dissolving into the intruded groundwater. Being an anionic species, the transport of Se-79 would be regulated by the metal oxides relevant minerals such as goethite and hematite (Jan et al., 2008). This is true that the transport of selenium in the shallow surface environment could be relatively easy to estimate by considering the amount of these metal oxides presenting in the soils and sediments. However, when dealing with deep geological repository, the transport of Se-79 becomes less predictable because of the much less content of metal oxide residing in the host rock such as granite. In order to conduct a reliable performance assessment of repository, it is very important to establish the correlation between selenium adsorption and the properties of potential host rock, in this study, the mineral and chemical compositions of Taiwan local granite. From this point of view, selenium adsorption experiments were conducted with 54 different Taiwan local granite samples collected from the depth ranging from 100 ∝ 400 meters below the surface. These granite samples represent a variety of deep geological environments, including the intact rock, groundwater intruded zones, and some weathered samples. Based upon our preliminary results, several solid conclusions could be made. First, the correlation coefficients between the Kd values and the mineral and chemical compositions are rather low (R-square values are often < 0.2). This points out the complexity of these geological samples and strongly suggests more efforts should be put into to acquire more relevant information. Second, the correlation between the selenium Kd values and the content of iron oxide (R-square 0.110) is much higher than that between the CEC of these granite samples (R-square 0.001). This clearly indicates that the minerals that

  7. Selenium-72 formation via {sup nat}Br(p,x) induced by 100 MeV Protons: Steps towards a novel {sup 72}Se/{sup 72}As generator system

    Energy Technology Data Exchange (ETDEWEB)

    Ballard, B. [Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Wycoff, D. [Department of Chemistry, University of Missouri-Columbia, Columbia, MO 65211 (United States); Birnbaum, E.R.; John, K.D. [Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Lenz, J.W. [John Lenz and Associates, East Lansing, MI 48823 (United States); Jurisson, S.S. [Department of Chemistry, University of Missouri-Columbia, Columbia, MO 65211 (United States); Cutler, C.S. [Missouri University Research Reactor Center, University of Missouri-Columbia, Columbia, MO 65211 (United States); Nortier, F.M.; Taylor, W.A. [Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Fassbender, M.E., E-mail: mifa@lanl.gov [Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2012-04-15

    Selenium-72 production by the proton bombardment of a natural NaBr target has been successfully demonstrated at the Los Alamos National Laboratory Isotope Production Facility (LANL-IPF). Arsenic-72 (half life 26 h) is a medium-lived positron emitting radionuclide with the major advantage of being formed as the daughter of another 'generator' radioisotope (Se-72, 8.5 d). A {sup 72}Se/{sup 72}As generator would be the preferred mechanism for clinical utilization of {sup 72}As for positron emission tomography (PET). No portable {sup 72}Se/{sup 72}As generator system has been demonstrated for convenient, repeated {sup 72}As elution ('milking'). In this work, we describe {sup 72}Se production and recovery from irradiated NaBr targets using a 100 MeV proton beam. We also introduce an {sup 72}As generator principle based on {sup 72}Se chelation followed by liquid-liquid extraction, which will be transferred to a solid-phase sorption/elution system. - Highlights: Black-Right-Pointing-Pointer A bulk production and processing method for {sup 72}Se using low-toxic NaBr in a high-energy proton beam has been developed. Black-Right-Pointing-Pointer A chelation based principle for a {sup 72}Se/{sup 72}As generator has been demonstrated. Black-Right-Pointing-Pointer Comparison of experimental yields to theoretical predictions resulted in good agreement.

  8. The influence of iodine and selenium supplementation on trace elemental contents in erythrocyte of the cretinism rats

    International Nuclear Information System (INIS)

    Liu Nianqing; Liu Pingsheng

    2001-01-01

    The contents of K, Ca, Mn, Fe, Cr, Cu, Zn, Rb and Pb in the erythrocyte of 5 groups of rats, were measured by PIXE and XRF. Four groups of the cretinism rats were continuously fed the feed from epidemic cretinism area. zone sandstone-type uranium deposit mineral haloes of intesupplementation. Control group was normal rats fed normal feed. Five weeks later the blood samples were collected. The erythrocyte was separated for the determination of elemental concentrations, the serum for the radioimmunoassay of thyroid hormones T3, T4, FT3, FT4 and rT3 status. The comparison among five groups and the correlation between elements and thyroid hormones were performed by using SPSS/PC statistical package. The results showed that comparing with non-supplementation or control groups the concentrations of Zn, Mn, Cu, or Rb in the groups of I and/or Se supplementation were significantly fluctuating, while thyroid hormones T4, FT4 and rT3 significantly increased

  9. 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

  10. Antioxidant activity of water extracts from fruit body of Lentinus edodes enriched with selenium

    Directory of Open Access Journals (Sweden)

    Savić Milena D.

    2011-01-01

    Full Text Available Shiitake (Lentinus edodes belongs to medically important and delicious fungi. It is recognizable for its healing properties, excellent taste and rich aroma. According to the traditional Japanese and Chinese medicine, shiitake mushroom significantly increases the strength and vitality of the body. Shiitake contains immunostimulants, compounds that lower cholesterol, prevents clogging of blood vessels, regulates the pressure, balances blood sugar levels, regulates digestion, and improves the performance of respiratory organs by its antirheumatic and antiallergic activities. Shiitake is recommended to use as food, prevention and cure, usually in a form of a spice (dried and ground or tea. It can be consumed fresh, too. The objective of this study was to test the effect of enrichment in selenium on antioxidant, reducing and free radical scavenging activity of water extracts from fruit body of Lentinus edodes. The fungus was enhanced by adding organic selenium, zinc (II complex with the ligand 2.6-bis diacetylpyridine (selenosemicarbazon and inorganic compounds (Na2SeO3 of selenium in nutritional substrate where the fungus was grown. The total selenium content in fruit body was around 50 ppm for the sample enriched with selenium originating from organic sources, and 80 ppm for the sample enriched with selenium from inorganic sources. Samples were prepared by extraction of fruiting bodies in heated water. The results indicated that water extracts of whole fruit bodies, from both control and mushrooms supplemented with selenium, had quite good antioxidant activity. However, there was no significant difference between the samples supplemented with selenium content and those that were not.

  11. Assessing arsenic and selenium in a single nail clipping using portable X-ray fluorescence

    International Nuclear Information System (INIS)

    Fleming, David E.B.; Nader, Michel N.; Foran, Kelly A.; Groskopf, Craig; Reno, Michael C.; Ware, Chris S.; Tehrani, Mina; Guimarães, Diana; Parsons, Patrick J.

    2017-01-01

    The feasibility of measuring arsenic and selenium contents in a single nail clipping was investigated using a small-focus portable X-ray fluorescence (XRF) instrument with monochromatic excitation beams. Nail clipping phantoms supplemented with arsenic and selenium to produce materials with 0, 5, 10, 15, and 20 µg/g were used for calibration purposes. In total, 10 different clippings were analyzed at two different measurement positions. Energy spectra were fit with detection peaks for arsenic K_α, selenium K_α, arsenic K_β, selenium K_β, and bromine K_α characteristic X-rays. Data analysis was performed under two distinct conditions of fitting constraint. Calibration lines were established from the amplitude of each of the arsenic and selenium peaks as a function of the elemental contents in the clippings. The slopes of the four calibration lines were consistent between the two conditions of analysis. The calculated minimum detection limit (MDL) of the method, when considering the K_α peak only, ranged from 0.210±0.002 µg/g selenium under one condition of analysis to 0.777±0.009 µg/g selenium under another. Compared with previous portable XRF nail clipping studies, MDLs were substantially improved for both arsenic and selenium. The new measurement technique had the additional benefits of being short in duration (~3 min) and requiring only a single nail clipping. The mass of the individual clipping used did not appear to play a major role in signal strength, but positioning of the clipping is important. - Highlights: • Portable X-ray fluorescence was used to assess As and Se in nail clipping phantoms. • Calibration lines were consistent between two different conditions of data analysis. • This new XRF approach was sensitive and required only a single nail clipping.

  12. Influence of selenium amount on the structural and electronic properties of Cu(In,Ga)Se{sub 2} thin films and solar cells formed by the stacked elemental layer process

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, B.J., E-mail: bjm.mueller@web.de [Institute of Micro- and Nanomaterials, University of Ulm, D-89081 Ulm (Germany); Corporate Research, Robert Bosch GmbH, D-71272 Renningen (Germany); Opasanont, B.; Haug, V. [Corporate Research, Robert Bosch GmbH, D-71272 Renningen (Germany); Hergert, F. [Bosch Solar CISTech GmbH, D-14772 Brandenburg (Germany); Zweigart, S. [Corporate Research, Robert Bosch GmbH, D-71272 Renningen (Germany); Herr, U., E-mail: ulrich.herr@uni-ulm.de [Institute of Micro- and Nanomaterials, University of Ulm, D-89081 Ulm (Germany)

    2016-06-01

    In the following article the influence of selenium supply on the stacked elemental layer process during the final annealing step is investigated. We find that the Se supply strongly influences the phase formation in the Cu(In,Ga)Se {sub 2} resulting in a modified Ga/In distribution. The effects of Se supply on the structural and electronic properties of the films are reported. The solar cell performance has been investigated in detail using current voltage and external quantum efficiency measurements. We find that the chalcopyrite crystal formation is strongly influenced by the Se supply during the growth process. Furthermore the interdiffusion of Ga and In is accelerated with increasing Se amount. This has direct consequences on band gap and series resistance, which leads to changes in the values of short-circuit current density, open-circuit voltage and fill factor. The open-circuit voltage increases with increasing band gap of the Cu(In,Ga)Se {sub 2}, whereas the short-circuit current density decreases with increasing band gap. The fill factor is affected by the formation of MoSe {sub 2} at the back contact. The experimental findings are compared with the theoretical efficiency limits calculated from the Shockley–Queisser model, and also with numerical 1D SCAPS simulations. - Highlights: • Adjustment of the Ga/In distribution by the Se supply • Enhanced Ga incorporation near-surface • Interdiffusion coefficients of Ga/In are investigated. • Shockley–Queisser modeling and 1D SCAPS simulations • Fill factor is strongly coupled on the MoSe2/Mo ratio.

  13. Effects of maternal dietary selenium (Se-enriched yeast) on testis development, testosterone level and testicular steroidogenesis-related gene expression of their male kids in Taihang Black Goats.

    Science.gov (United States)

    Shi, Lei; Song, Ruigao; Yao, Xiaolei; Duan, Yunli; Ren, Youshe; Zhang, Chunxiang; Yue, Wenbin; Lei, Fulin

    2018-07-01

    To investigate the effects of maternal dietary selenium (Se-enriched yeast) on testis development, testosterone level and steroidogenesis-related gene expression in testis of their male kids, selected pregnant Taihang Black Goats were randomly allotted to four treatment groups. They were fed the basal gestation and lactation diets supplemented with 0 (control), 0.5, 2.0 and 4.0 mg of Se/kg DM. Thirty days after weaning, testes were collected from the kids. After the morphological development status of testis was examined, tissue samples were collected for analyzing testosterone concentration and histological parameters. Testosterone synthesis-related genes were detected using real-time PCR. Localization and quantification of androgen receptor (AR) in testis of goats were determined by immunohistochemical and western blot analysis. The results show that Se supplementation in the diet of dams led to higher (p kids. Excessive Se (4.0 mg/kg) can inhibit the development of testis by decreasing testicular weight and volume. The density of spermatogenic cells and Leydig cells in the Se treatment groups was significantly (p kids by modulating testosterone synthesis in goats. More attention should be given to the potential role of maternal nutrition in improving reproductive performance of their offspring. Copyright © 2018 Elsevier Inc. All rights reserved.

  14. 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.

  15. 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)

  16. 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

  17. Damp Heat Treatment of Cu(In,GaSe2 Solar Cells with Different Sodium Content

    Directory of Open Access Journals (Sweden)

    Felix Daume

    2013-11-01

    Full Text Available Long term stability is crucial to maturing any photovoltaic technology. We have studied the influence of sodium, which plays a key role in optimizing the performance of Cu(In,GaSe2 (CIGSe solar cells, on the long-term stability of flexible CIGSe solar cells on polyimide foil. The standardized procedure of damp heat exposure (85% relative humidity at 85 °C was used to simulate aging of the unencapsulated cells in multiple time steps while they were characterized by current-voltage analysis, capacitance-voltage profiling, as well as electroluminescence imaging. By comparing the aging process to cells that were exposed to heat only, it could be confirmed that moisture plays the key role in the degradation process. We found that cells with higher sodium content suffer from a more pronounced degradation. Furthermore, the experimental results indicate the superposition of an enhancing and a deteriorating mechanism during the aging process. We propose an explanation based on the corrosion of the planar contacts of the solar cell.

  18. Substoichiometric determination of selenium with potassium ethyl xanthate

    International Nuclear Information System (INIS)

    Chandrasekhar Reddy, P.; Polaiah, B.; Rangamannar, B.

    1989-01-01

    A substoichiometric radiochemical method was developed for the determination of selenium with potassium ethyl xanthate. The selenium ethyl xanthate complex formed was extracted into chloroform from borate buffer at pH 5. The effect of foreign ions on the extraction was studied. Microgram quantities of selenium could be conveniently determined with a fair degree of accuracy. The method was successfully applied for the determination of selenium content in food stuffs such as 'Jaggery' and 'Wheat powder'. (author) 4 refs.; 3 figs

  19. Selenium Utilization Strategy by Microalgae

    Directory of Open Access Journals (Sweden)

    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.

  20. Overview and prospects of selenium phytoremediation approaches

    Science.gov (United States)

    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 ...

  1. 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 ...

  2. Studies in radioselenium 75Se distribution in tissues and rumen content and on its excretion with bile, urine and faeces in sheep

    International Nuclear Information System (INIS)

    Dejneka, J.; Nowosad, R.; Simoni, J.

    1979-01-01

    The studies were carried out on 11 mature sheep fistulated and cannulated from the gall bladder or rumen. Radioactive sodium selenate in aqueous solution was administered intravenously. Before selenium was given to the animal, rumen content or bile, as well as blood, urine and faeces were collected as control material. After selenium had been given, 10 ml of rumen content or 3 ml of bile were taken at 15-minute intervals during the first two hours, and then every 60 minutes up to the 96th hour of the trials. Urine and faeces were collected at 3-hour intervals. Blood was taken from the zygomatic vein once a day. After the 4th day of the trials, the sheep were anaesthetized and bled, and then samples were collected from various organs. Measurements of radioactivity were made in the samples. The greatest amount of selenium was found in the cortical part of the kidney, and the smallest amount in the vitreous body of the eye. (author)

  3. 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)

  4. 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)

  5. 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

  6. Alleviation of cadmium toxicity in cucumber (Cucumis sativus) seedlings by the application of selenium

    International Nuclear Information System (INIS)

    Sun, H.; Wang, X.; Wang, Y.; Wei, T.; Wang, G.

    2016-01-01

    In the present study, the role of selenium in cadmium toxicity was investigated in cucumber seedlings by hydroponic experiments. The application of Se for cucumber exposed to Cd significantly reduced Cd accumulation in all tissues, elevated Cd-depressed chlorophyll content, and improved photosynthetic performance. External Se significantly reduced ·OH, H2O2 and malondialdehyde content. Exogenous Se balanced Cd-depressed elements (e.g., Se enhanced Cd-induced decreases in root Zn, leaf/stem/root Mn concentrations) and carbohydrate contents. External Se also significantly decreased the Cd-induced increases in Na+K+-, Ca2+Mg2+- and total ATPase activities, which recovered almost to control level. Results indicate that application of Se can alleviate Cd toxicity in cucumber seedlings by reducing Cd uptake and reactive oxygen species (ROS) accumulation, moreover protecting photosynthetic machinery from damaging, balancing elements and carbohydrate contents, and improving ATPase activities in cucumber.

  7. Alleviation of cadmium toxicity in cucumber (Cucumis sativus) seedlings by the application of selenium

    Energy Technology Data Exchange (ETDEWEB)

    Sun, H.; Wang, X.; Wang, Y.; Wei, T.; Wang, G.

    2016-07-01

    In the present study, the role of selenium in cadmium toxicity was investigated in cucumber seedlings by hydroponic experiments. The application of Se for cucumber exposed to Cd significantly reduced Cd accumulation in all tissues, elevated Cd-depressed chlorophyll content, and improved photosynthetic performance. External Se significantly reduced ·OH, H2O2 and malondialdehyde content. Exogenous Se balanced Cd-depressed elements (e.g., Se enhanced Cd-induced decreases in root Zn, leaf/stem/root Mn concentrations) and carbohydrate contents. External Se also significantly decreased the Cd-induced increases in Na+K+-, Ca2+Mg2+- and total ATPase activities, which recovered almost to control level. Results indicate that application of Se can alleviate Cd toxicity in cucumber seedlings by reducing Cd uptake and reactive oxygen species (ROS) accumulation, moreover protecting photosynthetic machinery from damaging, balancing elements and carbohydrate contents, and improving ATPase activities in cucumber.

  8. Investigation of electrical noise in selenium-immersed thermistor bolometers

    Science.gov (United States)

    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.

  9. Influence of different sulfur to selenium ratios on the structural and electronic properties of Cu(In,Ga)(S,Se){sub 2} thin films and solar cells formed by the stacked elemental layer process

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, B. J., E-mail: bjm.mueller@web.de [Robert Bosch GmbH, Corporate Research and Advance Engineering, Advanced Functional Materials and Microsystems, D-70839 Gerlingen (Germany); Institute of Micro- and Nanomaterials, University of Ulm, D-89081 Ulm (Germany); Zimmermann, C.; Haug, V., E-mail: veronika.haug@de.bosch.com; Koehler, T.; Zweigart, S. [Robert Bosch GmbH, Corporate Research and Advance Engineering, Advanced Functional Materials and Microsystems, D-70839 Gerlingen (Germany); Hergert, F. [Bosch Solar CISTech GmbH, D-14772 Brandenburg (Germany); Herr, U., E-mail: ulrich.herr@uni-ulm.de [Institute of Micro- and Nanomaterials, University of Ulm, D-89081 Ulm (Germany)

    2014-11-07

    In this study, we investigate the effect of different elemental selenium to elemental sulfur ratios on the chalcopyrite phase formation in Cu(In,Ga)(S,Se){sub 2} thin films. The films are formed by the stacked elemental layer process. The structural and electronic properties of the thin films and solar cells are analyzed by means of scanning electron microscopy, glow discharge optical emission spectrometry, X-ray diffraction, X-ray fluorescence, Raman spectroscopy, spectral photoluminescence as well as current-voltage, and quantum efficiency measurements. The influence of different S/(S+Se) ratios on the anion incorporation and on the Ga/In distribution is investigated. We find a homogenous sulfur concentration profile inside the film from the top surface to the bottom. External quantum efficiency measurements show that the band edge of the solar cell device is shifted to shorter wavelength, which enhances the open-circuit voltages. The relative increase of the open-circuit voltage with S/(S+Se) ratio is lower than expected from the band gap energy trend, which is attributed to the presence of S-induced defects. We also observe a linear decrease of the short-circuit current density with increasing S/(S+Se) ratio which can be explained by a reduced absorption. Above a critical S/(S+Se) ratio of around 0.61, the fill factor drops drastically, which is accompanied by a strong series resistance increase which may be attributed to changes in the back contact or p-n junction properties.

  10. 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

  11. 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.

  12. Arsenic and selenium in microbial metabolism

    Science.gov (United States)

    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.

  13. Blood selenium levels and contribution of food groups to selenium intake in adolescent girls in Iceland.

    Science.gov (United States)

    Gudmundsdottir, Edda Y; Gunnarsdottir, Ingibjorg; Thorlacius, Arngrimur; Reykdal, Olafur; Gunnlaugsdottir, Helga; Thorsdottir, Inga; Steingrimsdottir, Laufey

    2012-01-01

    Significant changes have been reported in dietary habits and food availability in Iceland that would be expected to compromise selenium intake and status, especially among young people. These include substantial decreases in the consumption of fish and milk, as well as the selenium content of imported wheat. The aim of this study was to assess selenium in the diet and whole blood of adolescent girls, as well as define the most important foods contributing to intake and blood concentrations of selenium. The subjects were 96 randomly selected girls, aged 16-20, who answered a validated food frequency questionnaire (FFQ) for dietary assessment. Selenium intake from each food group was calculated in µg/day. Blood samples were collected for measurement of whole blood selenium. Mean dietary selenium was 51±25 µg/day. Milk/dairy products, including cheese, contributed 36±14% of total dietary selenium; fish 18±12%; and bread/cereal products 13±6%. Mean whole blood selenium was 117±12 µg/l (range 90-208); nearly 90% of subjects were above the optimal level of 100 µg/l. Fish and bread/cereal products were the only foods significantly correlated with selenium in blood (r=0.32; P=0.002 and r=0.22; P=0.04, respectively) while no correlation was found with milk and dairy products in spite of their greater contribution to total selenium intake. In this population of Icelandic adolescent girls, selenium intake and status seem acceptable. Judging from associations between intake and blood levels, fish and cereals may be the most important contributors to blood selenium.

  14. Blood selenium levels and contribution of food groups to selenium intake in adolescent girls in Iceland

    Directory of Open Access Journals (Sweden)

    Ingibjorg Gunnarsdottir

    2012-08-01

    Full Text Available Background/objectives: Significant changes have been reported in dietary habits and food availability in Iceland that would be expected to compromise selenium intake and status, especially among young people. These include substantial decreases in the consumption of fish and milk, as well as the selenium content of imported wheat. The aim of this study was to assess selenium in the diet and whole blood of adolescent girls, as well as define the most important foods contributing to intake and blood concentrations of selenium. Design: The subjects were 96 randomly selected girls, aged 16–20, who answered a validated food frequency questionnaire (FFQ for dietary assessment. Selenium intake from each food group was calculated in µg/day. Blood samples were collected for measurement of whole blood selenium. Results: Mean dietary selenium was 51±25 µg/day. Milk/dairy products, including cheese, contributed 36±14% of total dietary selenium; fish 18±12%; and bread/cereal products 13±6%. Mean whole blood selenium was 117±12 µg/l (range 90–208; nearly 90% of subjects were above the optimal level of 100 µg/l. Fish and bread/cereal products were the only foods significantly correlated with selenium in blood (r=0.32; P = 0.002 and r=0.22; P = 0.04, respectively while no correlation was found with milk and dairy products in spite of their greater contribution to total selenium intake. Conclusion: In this population of Icelandic adolescent girls, selenium intake and status seem acceptable. Judging from associations between intake and blood levels, fish and cereals may be the most important contributors to blood selenium.

  15. Nd2(SeO3)2(SeO4) . 2H2O - a mixed-valence compound containing selenium in the oxidation states +IV and +VI

    International Nuclear Information System (INIS)

    Berdonosov, P.S.; Dityat'yev, O.A.; Dolgikh, V.A.; Schmidt, P.; Ruck, Michael; Lightfoot, P.

    2004-01-01

    Pale pink crystals of Nd 2 (SeO 3 ) 2 (SeO 4 ) . 2H 2 O were synthesized under hydrothermal conditions from H 2 SeO 3 and Nd 2 O 3 at about 200 C. X-ray diffraction on powder and single-crystals revealed that the compound crystallizes with the monoclinic space group C 2/c (a = 12.276(1) A, b = 7.0783(5) A, c = 13.329(1) A, β = 104.276(7) ). The crystal structure of Nd 2 (SeO 3 ) 2 (SeO 4 ) . 2H 2 O is an ordered variant of the corresponding erbium compound. Eight oxygen atoms coordinate the Nd III atom in the shape of a bi-capped trigonal prism. The oxygen atoms are part of pyramidal (Se IV O 3 ) 2- groups, (Se VI O 4 ) 2- tetrahedra and water molecules. The [NdO 8 ] polyhedra share edges to form chains oriented along [010]. The selenate ions link these chains into layers parallel to (001). The layers are interconnected by the selenite ions into a three-dimensional framework. The dehydration of Nd 2 (SeO 3 ) 2 (SeO 4 ) . 2H 2 O starts at 260 C. The thermal decomposition into Nd 2 SeO 5 , SeO 2 and O 2 at 680 C is followed by further loss of SeO 2 leaving cubic Nd 2 O 3 . (Abstract Copyright [2004], Wiley Periodicals, Inc.) [de

  16. Selenium status in cattle herds in Wallonia (Belgium: overview and health management

    Directory of Open Access Journals (Sweden)

    Youcef Mehdi

    2014-12-01

    Full Text Available Aim: Monitoring was performed in order to determine the Selenium (Se status of cattle herds in different agricultural areas in Wallonia (Belgium. Materials and Methods: The study included 114 heifers and 184 cows (82 dairy and 102 beef cows from 66 cattle farms situated in Wallonia. The Se status was assessed by measuring the glutathion peroxydase in red cells and converting it to the equivalent Se blood content. Results: The average blood concentrations of Se were very low. The Ardennes region was an area where the lowest Se status was recorded. The highest levels of Se in dairy cows and beef cows were recorded respectively in the limoneuse region and Famenne areas. The Se content in beef herds was lower compared with that of dairy herds (35 vs. 56 μg/L, p<0.01. Conclusion: On average over all the regions, 87% of animals were classified as deficient and only 13% of the animals were classified as adequate. The heifers from both dairy and beef herds in Wallonia exhibited a deficiency in Se classified as moderate to severe. The beef herds showed larger deficiencies compared with the dairy herds. Selenium deficiency can be prevented by ensuring adequate supplementation of deficient animals in Se deficient regions. An increased consumption of vitamin-mineral supplements, the use of Se-enriched fertilizers and ingredients containing high levels of Se can help to reduce or correct deficiencies recorded in cattle herds in Wallonia.

  17. Impact of Selenium Addition to Animal Feeds on Human Selenium Status in Serbia

    Directory of Open Access Journals (Sweden)

    Zoran Pavlovic

    2018-02-01

    Full Text Available Research conducted during the 1980s demonstrated Se deficiency in humans. Increased inclusion of selenium in animal feeds started from the year 2000 onwards. The aim of this study was to estimate the effects of selenium inclusion in animal feeds on human selenium status and dietary habits of the Serbian population related to food of animal origin. Plasma selenium concentration in healthy adult volunteers, including residents of one of the regions with the lowest (Eastern Serbia, n = 60 and of one of the regions with the highest Se serum levels reported in the past (Belgrade, n = 82, was determined by hydride generation atomic absorption spectrometry. Multivariate analysis was employed to determine the correlation between Se plasma levels and dietary intake data derived from food frequency questionnaires and laboratory tests. The mean plasma Se level of the participants was 84.3 ± 15.9 μg/L (range: 47.3–132.1 μg/L, while 46% of participants had plasma Se levels lower than 80 μg/L. Frequency of meat, egg, and fish consumption was significantly correlated with plasma selenium level (r = 0.437, p = 0.000. Selenium addition to animal feed in the quantity of 0.14 mg/kg contributed to the improvement of human plasma selenium levels by approximately 30 μg/L.

  18. Monitoring of selenium in macrophytes - the case of Slovenia.

    Science.gov (United States)

    Mechora, Špela; Germ, Mateja; Stibilj, Vekoslava

    2014-09-01

    This paper examines macrophytes from various locations in Slovenian streams for selenium (Se) content in an attempt to discover if Se contamination is present and if Se uptake varies between sampling sites. For this purpose, macrophytes and water from ten locations in the Notranjska and Central regions (Slovenia) with different land use in the catchment were sampled. To assess the environmental conditions of the streams the Riparian, Channel, and Environment (RCE) inventory was applied, which revealed that investigated stretches of streams fall into RCE classes III, IV and V. The concentration of Se in water at all locations was less than 1μgSeL(-1). The Se content in macrophytes differed between sampling sites, with the highest content of Se in samples from Žerovniščica stream and the lowest in samples from Lipsenjščica stream. The content of Se was the highest in moss samples (3038ngSeg(-1) DM) and in the amphibious species Veronica anagallis-aquatica (1507ngSeg(-1) DM). Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Vitamin C, Phenolic Compounds and Antioxidant Capacity of Broccoli Florets Grown under Different Nitrogen Treatments Combined with Selenium

    Directory of Open Access Journals (Sweden)

    Peñas Elena

    2018-06-01

    Full Text Available Broccoli consumption is rising worldwide and fertilization is a tool to increase its production. However, little is known about the effect of mineral supplementation to the soil on the bioactive compounds. Therefore, the aim of this investigation was to analyze the content of vitamin C, total phenolic compounds and the antioxidant capacity of broccoli florets cultivated under different nitrogen (N conditions in combination with selenium (IV and VI. Greenhouse experiments were conducted in broccoli grown in commercial soil treated with different N sources [(NH42SO4, NaNO3, NH4NO3 or CO(NH22 at 160 kg N/ha]. In addition, selenium (Se salts [Na2SeO3 (Se IV or Na2SeO4 (Se VI at 10 and 20 kg Se/ha] were applied. There were no evidences of the influence of N treatment on vitamin C content whilst Se (IV or VI uptake led to a significant reduction of this vitamin in broccoli florets, irrespective of the N source. In contrast, total phenolics content and antioxidant capacity underwent a significant increment under N application. However, their combination with Se salts modified total phenolic content and antioxidant capacities in broccoli florets depending on N source and Se doses. Among all the experimental trials, application of NH4NO3 combined with 10 g Se (IV/ha was the elective treatment strategy to produce broccoli florets with higher content of phenolic compounds and antioxidant capacity and, therefore, enhanced functionality.

  20. Status of selenium in cancer prevention

    Science.gov (United States)

    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...

  1. The occurrence and origin of selenium minerals in Se-rich stone coals, spoils and their adjacent soils in Yutangba, China

    Czech Academy of Sciences Publication Activity Database

    Zhu, J.M.; Johnson, T.M.; Finkelman, R.B.; Zheng, B.S.; Sýkorová, Ivana; Pešek, J.

    2012-01-01

    Roč. 330, November (2012), s. 27-38 ISSN 0009-2541 Institutional support: RVO:67985891 Keywords : native Se * Cu-selenides * mandarinoite Subject RIV: DD - Geochemistry Impact factor: 3.154, year: 2012 http://www.sciencedirect.com/science/article/pii/S0009254112003828

  2. 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.

  3. Selenium in bread and durum wheats grown under a soil-supplementation regime in actual field conditions, determined by cyclic and radiochemical neutron activation analysis

    International Nuclear Information System (INIS)

    Catarina Galinha; Maria do Carmo Freitas; Marek Fikrle; Jan Kucera; Wolterbeek, H.T.

    2015-01-01

    This work focuses on the ability of bread and durum wheat to accumulate selenium (Se) via a soil-addition procedure at sowing time. Total Se in mature-grain samples was determined by neutron activation analysis (cyclic and radiochemical). Results show that Se-supplementation at the top rate (100 g Se ha -1 ) can increase Se contents up to 2, 16, 18 and 20 times for Jordao, Roxo, Marialva and Celta cultivars, respectively, when compared to their unsupplemented crops. These findings do not preclude the need for weighing up an eventual trade-off between agrochemical costs, field logistics and Se recovery for alternative Se-biofortification methods. (author)

  4. Effect of application of fertilizer nitrogen, zinc and selenium on zinc nutrition of ryegrass

    International Nuclear Information System (INIS)

    Wei Dongpu; Bai Lingyu; Yao Yunyin; Hua Luo

    2001-01-01

    A pot experiment was carried out to study the effect of zinc or selenium fertilizer applied alone, combined application of nitrogen, zinc and selenium fertilizer on zinc nutrition of ryegrass in mono culture or in mixed culture in mountain yellow-brown earth of Hubei province. The results showed that: 1) Zn content was enhanced by mixed culture (white clover: ryegrass = 1:4), at the same time, Zn content of ryegrass in mixed culture was increased with increasing of Zn fertilizer. 2) The main reason of Zn content of ryegrass decreased in mixed culture was dilution effect due to the increase of dry weight. 3) In mono-Se treatment, Zn content of ryegrass in mixed culture was decreased with increasing of Se fertilizer. 4) In 9 treatment of combined applications of N, Zn and Se fertilizer, treatment of the highest Zn content of ryegrass in mixed culture was N46Zn25Se1; treatment of the highest Zn content of ryegrass in mono culture was N30Zn25Se5

  5. [Selenium treatment in thyreopathies].

    Science.gov (United States)

    Sotak, Štefan

    Selenium (latin Selenium) is a micronutrient embedded in several proteins. In adults, the thyroid is the organ with the highest amount of selenium per gram of tissue. Selenium levels in the body depend on the characteristics of the population and its diet and geographic area. In the thyroid, selenium is required for the antioxidant function and for the metabolism of thyroid hormones. The literature suggests that selenium supplementation of patients with Hashimotos thyroiditis is associated with a reduction in antithyroperoxidase antibody levels. Selenium supplementation also in mild Graves orbitopathy is associated with delayed progression of ocular disorders. As a consequence of this observation The European Group on Graves Orbitopathy recommend six months selenium preparates supportive therapy for patients with mild form of Graves orbitopathy.Key words: Graves-Basedows disease - Hashimotos thyroiditis - selenium - supplementation.

  6. Certification of the content (mass fractions) of arsenic, cadmium, copper, cobalt, manganese, lead, selenium and zinc in a single-cell protein. CRM no. 274

    Energy Technology Data Exchange (ETDEWEB)

    Griepink, B

    1987-01-01

    This report describes the preparation of a single cell protein as a reference material. Homogeneity and stability of the material are studied. The applied methods for the determination of concentrations of As, Cd, Cu, Co, Mn, Pb, Se, and Zn are presented, the contents of which are resp.: 0.1, 0.03, 0.04, 13, 52, 0.04, 1 and 43 ..mu..g/g. With 5 graphs, 55 tabs.

  7. Multiple sources of selenium in ancient seafloor hydrothermal systems: Compositional and Se, S, and Pb isotopic evidence from volcanic-hosted and volcanic-sediment-hosted massive sulfide deposits of the Finlayson Lake District, Yukon, Canada

    Science.gov (United States)

    Layton-Matthews, Daniel; Leybourne, Matthew I.; Peter, Jan M.; Scott, Steven D.; Cousens, Brian; Eglington, Bruce M.

    2013-09-01

    Volcanic-hosted massive sulfide (VHMS) and volcanic-sediment-hosted massive sulfide (VSHMS; i.e., hosted by both volcanic and sedimentary rocks) deposits in the Finlayson Lake District, Yukon, Canada, provide a unique opportunity to study the influence of seafloor and sub-seafloor hydrothermal processes on the formation of Se-poor (GP4F VHMS deposit; 7 ppm Se average), intermediate (Kudz Ze Kayah—KZK VHMS deposit; 200 ppm Se average), and Se-enriched (Wolverine VSHMS deposit; 1100 ppm Se average) mineralization. All three deposits are hosted by mid-Paleozoic (˜360-346 Ma) felsic volcanic rocks, but only the Wolverine deposit has voluminous coeval carbonaceous argillites (black shales) in the host rock package. Here we report the first application of Se isotope analyses to ancient seafloor mineralization and use these data, in conjunction with Pb and S isotope analyses, to better understand the source(s) and depositional process(es) of Se within VHMS and VSHMS systems. The wide range of δ82Se (-10.2‰ to 1.3‰, relative to NIST 3149), δ34S (+2.0‰ to +12.8‰ CDT), and elevated Se contents (up to 5865 ppm) within the Wolverine deposit contrast with the narrower range of δ82Se (-3.8‰ to -0.5‰), δ34S (9.8‰ to 13.0‰), and lower Se contents (200 ppm average) of the KZK deposit. The Wolverine and KZK deposits have similar sulfide depositional histories (i.e., deposition at the seafloor, with concomitant zone refining). The Se in the KZK deposit is magmatic (leaching or degassing) in origin, whereas the Wolverine deposit requires an additional large isotopically negative Se source (i.e. ˜-15‰ δ82Se). The negative δ82Se values for the Wolverine deposit are at the extreme light end for measured terrestrial samples, and the lightest observed for hypogene sulfide minerals, but are within calculated equilibrium values of δ82Se relative to NIST 3149 (˜30‰ at 25 °C between SeO4 and Se2-). We propose that the most negative Se isotope values at the

  8. 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.

  9. 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.

  10. Reactivity of uranium(IV) bridged chalcogenido complexes UIV–E–UIV (E = S, Se) with elemental sulfur and selenium: synthesis of polychalcogenido-bridged uranium complexes

    OpenAIRE

    Franke, Sebastian M.; Heinemann, Frank W.; Meyer, Karsten

    2014-01-01

    We report the syntheses, electronic properties, and molecular structures of a series of polychalcogenido-bridged dinuclear uranium species. These complexes are supported by the sterically encumbering but highly flexible, single N-anchored tris(aryloxide) chelator (AdArO)3N3−. Reaction of an appropriate uranium precursor, either the U(III) starting material, [((AdArO)3N)U(DME)], or the dinuclear mono-chalcogenido-bridged uranium(IV/IV) compounds [{((AdArO)3N)U(DME)}2(μ-E)] (E = S, Se), with el...

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

    Science.gov (United States)

    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.

  12. Effects of the copper content on the structural and electrical properties of Cu2ZnSnSe4 bulks

    Science.gov (United States)

    Tsega, Moges; Dejene, F. B.; Koao, L. F.

    2016-01-01

    We have investigated the concept of defect in CuxZnSnSe4 (x=1.6-2.0) and Cuy(Zn0.9Sn1.1)Se4 (y= 1.6-2.0) bulks prepared by liquid-phase sintering at 600 °C for 2 h with soluble sintering aids of Sb2S3 and Te. All samples were found to exhibit p-type semiconductor for CuxZnSnSe4, while n-type of behavior obtained at y= 1.8-2.0 for Cuy(Zn0.9Sn1.1)Se4 pellets. The Cu vacancy acts as an acceptor point defect to form the p-type semiconductor, and Sn4+ acts as a donor to form the n-type behavior for the Sn-rich CZTSe. SEM images of pellets show dense surface morphology, and increase in grain size upon Cu inclusion. The largely increased Hall mobility and the slightly changed carrier concentration for Cuy(Zn0.9Sn1.1)Se4 with increasing the Cu content is related to the types of its defects. At y=2.0 with carrier concentration of 4.88×1017 cm-3 showed the highest mobility of around 58 cm2/V s. Based upon the proposed point defects, the CZTSe property can be consistently explained.

  13. Microstructure characterization of the soda-lime-glass/copper-indium-gallium-selenium interface in Cu-poor Cu(In,Ga)Se{sub 2} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jian, E-mail: wangjustb@gmail.com; Qiao, Yi; Zhu, Jie, E-mail: jiezhu@ustb.edu.cn

    2015-05-29

    The microstructure characteristics of the soda-lime-glass/Cu(In,Ga)Se{sub 2} (SLG/CIGS) interface in Cu-poor CIGS films are investigated by transmission electron microscopy and selected area electronic diffraction (SAED). The SAED patterns show very sharp and strong spots, indicating the main structure of CIGS chalcopyrite. Small dispersed crystals with size distribution from 2 to 5 nm seem to be embedded in amorphous matrix, and additional spots indicate the presence of an ordered vacancy compound (OVC). This observation is consistent with the Raman results, and the OVC phase with the nanoclusters exists in the CIGS matrix, instead of layer structure. Lattice distortion results in local changes in contrast. Some pseudo-disordered structure is observed, however, the structure is actually the chalcopyrite CIGS structure. 180° rotation twins are also observed at the SLG/CIGS interface. Lattice distortion is widely observed at the interface of the Cu-poor CIGS films, and the extra spots could be caused by different lattice orientations. - Highlights: • Cu(In,Ga)Se{sub 2} (CIGS) were prepared on bare soda-lime-glass (SLG) substrates. • Microstructure of the SLG/CIGS interface was investigated. • An ordered vacancy compound (OVC) phase was observed. • The OVC phase with nanoclusters exists in the CIGS matrix, instead of layer structure. • 180° rotation twins were observed at the SLG/CIGS interface.

  14. 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.

  15. 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.

  16. Methods of making copper selenium precursor compositions with a targeted copper selenide content and precursor compositions and thin films resulting therefrom

    Science.gov (United States)

    Curtis, Calvin J [Lakewood, CO; Miedaner, Alexander [Boulder, CO; van Hest, Marinus Franciscus Antonius Maria; Ginley, David S [Evergreen, CO; Leisch, Jennifer [Denver, CO; Taylor, Matthew [West Simsbury, CT; Stanbery, Billy J [Austin, TX

    2011-09-20

    Precursor compositions containing copper and selenium suitable for deposition on a substrate to form thin films suitable for semi-conductor applications. Methods of forming the precursor compositions using primary amine solvents and methods of forming the thin films wherein the selection of temperature and duration of heating controls the formation of a targeted species of copper selenide.

  17. Selenium Status in Heifers, Late Pregnancy Cows and Their Calves in the Šumava Region, Czech Republic

    Directory of Open Access Journals (Sweden)

    P. Slavík

    2007-01-01

    Full Text Available The objective of this study was to ascertain selenium status in beef cattle in different stages of production in the Šumava region. In the region, blood collections and analyses for selected metabolic variables were performed in 54 animals in different production stages (18 heifers, 18 cows in late pregnancy and 18 calves aged 3 weeks on the average. Three herds were studied. The selenium status was determined both directly by measuring serum selenium (Se contents and indirectly by measuring glutathione peroxidase (GSH-Px activity in whole blood. The mean serum selenium concentration in all the animals under study (n = 54 was 30.6 μg/l +/- 2.91, and mean GSH-Px activity was 167.01 μkat/l +/- 92.39. In heifers, mean serum selenium concentration was 34.81 μg/l +/- 13.84; mean GSHPx activity was 186.96 μkat/l +/- 112.15. In late pregnancy cows, mean serum selenium concentration was 26.58 μg/l +/- 8.01, mean GSH-Px activity was 94.55 +/- 35.72 μkat/l. In calves, mean serum selenium concentration and GSH-Px activity were 30.41 μg/l +/- 12 and 219.54 μkat/l +/- 64.41, respectively. There was a statistically significant difference between the heifers and late pregnancy cows in both variables under study. However, between the late pregnancy cows and the calves, only the difference in GSH-Px activity was significant. The results indicate severe Se deficiency in the animals under study. It means apart from other things that mineral licks used did not provide enough minerals to meet the basic requirements of the animals.

  18. Production of selenium-enriched milk and dairy products

    Directory of Open Access Journals (Sweden)

    Csapó J.

    2015-01-01

    Full Text Available Until the middle of the last century, selenium was considered to be toxic, but recently it turned out to be a micronutrient with important physiological effects, whose lack impedes the functioning of several enzymes, while in the case of a prolonged deficiency, disease processes can also occur in the body. Hungary belongs to the selenium-deficient regions in Europe; therefore, our aim was to contribute to the improvement of selenium supply of the population through increasing the selenium content of milk and dairy products. A daily supplementation of 1-6 mg organic selenium to the feed of dairy cows increases the selenium content of milk from the value of 18 μg/kg to 94 μg/kg in 8 weeks, decreasing again to the initial value in 6 weeks after stopping the supplementation.

  19. Speciation of Se and DOC in soil solution and their relation to Se bioavailability.

    Science.gov (United States)

    Weng, Liping; Vega, Flora Alonso; Supriatin, Supriatin; Bussink, Wim; Van Riemsdijk, Willem H

    2011-01-01

    A 0.01 M CaCl(2) extraction is often used to asses the bioavailability of plant nutrients in soils. However, almost no correlation was found between selenium (Se) in the soil extraction and Se content in grass. The recently developed anion Donnan membrane technique was used to analyze chemical speciation of Se in the 0.01 M CaCl(2) extractions of grassland soils and fractionation of DOC (dissolved organic carbon). The results show that most of Se (67-86%) in the extractions (15 samples) are colloidal-sized Se. Only 13-34% of extractable Se are selenate, selenite and small organic Se (<1 nm). Colloidal Se is, most likely, Se bound to or incorporated in colloidal-sized organic matter. The dominant form of small Se compounds (selenate, selenite/small organic compounds) depends on soil. A total of 47-85% of DOC is colloidal-sized and 15-53% are small organic molecules (<1 nm). In combination with soluble S (sulfur) and/or P (phosphor), concentration of small DOC can explain most of the variability of Se content in grass. The results indicate that mineralization of organic Se is the most important factor that controls Se availability in soils. Competition with sulfate and phosphate needs to be taken into account. Further research is needed to verify if concentration of small DOC is a good indicator of mineralization of soil organic matter.

  20. Aquatic Life Criterion - Selenium

    Science.gov (United States)

    Documents pertaining to the 2016 Acute and Chronic Ambient Aquatic Life Water Quality Criteria for Selenium (Freshwater). These documents include what the safe levels of Selenium are in water for the majority of species.

  1. 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)

  2. La comunicación publicitaria se pone de moda: branded content y fashion films / Advertising communication gets fashionable: branded content and fashion films

    Directory of Open Access Journals (Sweden)

    Cristina DEL PINO-ROMERO

    2015-01-01

    Full Text Available Los cambios vividos por la industria comunicativa en los últimos años, entre otros motivos debido al auge de las redes sociales, han convertido a los contenidos, informativos o de entretenimiento, en la piedra angular para hacer llegar el mensaje publicitario al destinatario. El esfuerzo por parte de los anunciantes de tener una estrategia de contenidos definida para su presencia en medios sociales o nuevos formatos comunicativos como el branded content, son ejemplo de que el advertainment está actualmente de moda. Este artículo se centra en el branded content y en otro ejemplo de esta tendencia: los fashion films, un nuevo género publicitario que ha irrumpido especialmente en los sectores de la moda y los productos de lujo, con el fin, entre otros, de ofrecer una nueva visión de éstos basada en la originalidad, contando historias que conecten con su público objetivo.

  3. Selenium determination by fluorimetric method

    International Nuclear Information System (INIS)

    Lavorenti, A.

    1981-01-01

    A fluorimetric method to determine selenium both in vegetable samples and blood serum is developed. The method consists of a radioisotope 75 Se initially in order to optimize the determination of analytical conditions. Three samples digestion processes and also some factors related to methodology is studied. The nitric-percloric digestion process for 40 samples and the analytical process is shown. (M.J.C.) [pt

  4. 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...

  5. Selenium and Human Health

    Directory of Open Access Journals (Sweden)

    M Abedi

    2013-04-01

    Full Text Available Introduction: Selenium is an essential element for human health and it is toxic at high concentrations. Selenium is a constituent component of selenoproteins that have enzymatic and structural roles in human biochemistry. Selenium is a best antioxidant and catalyst for production of thyroid hormone. This element has the key role in the immune function; prevention of AIDS progression and the deactivity of toxins. Furthermore, selenium is essential for sperm motility and can reduce abortions. Selenium deficiency was also associated with adverse mood states. The findings regarding cardiovascular disease risk related to selenium deficiency is unclear, though other conditions such as vascular inflammation, oxidative stress and selenium deficiency can cause this disease too. Moreover, consuming of 60 mg of selenium per day may be associated with reduction of cancer risk. In this study, a review of studies has been performed on the biochemical function of selenium toxicity, and its effects on human health. Furthermore, certain identified cancers associated with selenium have been discussed to absorb more attention to the status of this element and also as a guide for further studies. Selenium plays the dual character (useful and harmful in human health, and then it is necessary to determine the concentration of this element in body fluids and tissues. An appropriate method for routine measurement of selenium in clinical laboratories is electro thermal atomic absorption spectrometry (ETAAS with very low detection limit and good precision.

  6. 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...

  7. 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.

  8. 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

    nutrient solution was a modified Hoagland’s solution and each plant received 400 mL nutrient daily. Selenium concentrations were added by 0, 3, 7 µM Na2SeO3 (Merck, Germany 10 days after transplanting. Leaf number (by counting, leaf area (with leaf area meter, relative water content (RWC, membrane stability index (MSI, chlorophyll and carotenoids content were determined one month after treatment applications. All data were subjected to one-way ANOVA by Statistix 8 (Tallahassee FL, USA and the means were compared for significance by the least significant difference (LSD test at p < 0.05. Results and Discussion: The results showed that selenium supplement at 5 µM significantly increased relative water content by 12.8% compared to control. Se increased root growth and thus absorbed more water and increased RWC in present experiment. Selenium at 7 and 10 µM Se increased membrane stability index by 33.61 and 80.06, respectively, compared to control which may be due to increasing potassium by Se application. Selenium at 3 and 5 µM increased leaf area by 24.6% and 25.1% relation to plants which were grown without Se supplementation. Leaf number increased by application of 5 µM Se about 15.14% and chlorophyll a, b and total increased by 64.67%, 38.5% and, 55.8%, respectively, in comparison with plants grown without Se application. Carotenoid content was not affected by different Se concentrations. Se increase chlorophyll content by increasing Mg and Fe absorption, or protect of chlorophyll content against chloroplast enzymes. The highest leaf area was observed at 3 µM Se in comparison with other treatments. Se at 5 µM is beneficial for growth, photosynthesis pigments, and leaf area and leaf number. Se application had no beneficial influence on lateral shoot. The highest starch concentration was observed at 5 µM Se in comparison with other treatments and control (by about 60% in comparison with plants were grown without Se application. Conclusion: In general, the result

  9. Studies on 75Se accumulation in rice plants and its effect on yield

    International Nuclear Information System (INIS)

    Prasad, T.; Arora, S.P.

    1980-01-01

    Radioactive selenium ( 75 Se) as sodium selenosulphate was applied to 8 kg soil per pot so as to get selenium concentration of 0, 0.270, 0.515, 0.764, 1.032 and 1.588 ppm in treatment groups I to VI, respectively. Pusa 2.21 paddy seedlings were transplanted and grown in the pots by conventional procedure. Both grain and straw yields decreased with increase in selenium dose upto 0.764 ppm. Mean dry grain yields per plant at harvest were 6.96, 5.31, 4.30, 3.33, 3.13 and 3.13 g and straw yields were 4.96, 4.05, 3.69, 3.19, 3.56 and 3.72 g, respectively, in treatments I to VI. Maximum plant height per plant also showed a decreasing trend with progressive increase in selenium upto a level of 0.764 ppm. At harvest, the selenium content in treatments I to VI was 0, 2.34, 4.29, 8.01, 10.99 and 12.80 ppm in straw and 0, 1.31, 2.81, 5.92, 9.92 and 10.76 ppm in grains, respectively. Selenium accumulation varied from 5.24 to 9.78 times in grains and 8.06 to 11.66 times in straw as per the dose applied to the soil. (author)

  10. Plasma selenium concentrations are sufficient and associated with protease inhibitor use in treated HIV-infected adults

    Science.gov (United States)

    Background: Selenium (Se) is an essential constituent of selenoproteins which play significant roles in antioxidant defense and inflammatory cascades. Selenium deficiency is associated with disease states characterized by inflammation including cardiovascular disease (CVD). While HIV infection has b...

  11. EDXS and XRD Analyses of Coleus with Different Concentration Selenium Supplements Under Lead Stress

    Directory of Open Access Journals (Sweden)

    QIN Hui-yuan

    2014-04-01

    Full Text Available In order to study the changes of the morphologies and element composition in Coleus hlumei Benth(Coleusroots and leaves under1.0 mmol·L-1 Pb2+ stress with selenium ( Setreatments, and to preliminarily investigate the relief mechanism of Se level on lead toxicity from the perspective of spectroscopy, Coleus was cultivated in nutrient solutions with different concentrations of Se. The results showed that the content of C, K and Ca elements in roots decreased, while 0, Mg, Al, Si, Fe and Pb elements increased under Pb stress with Se treatments. In addi-tion, the content of C, Mg, Al, Si, K, Ca and Fe elements in leaves decreased, while 0 and Cl elements increased. The element species and its contents in roots were changed obviously under Pb stress with Se treatments, and crystalline solid and crystal phase in roots were correspond-ingly changed.

  12. Comparison of Selenium Toxicity in Sunflower and Maize Seedlings Grown in Hydroponic Cultures.

    Science.gov (United States)

    Garousi, Farzaneh; Veres, Szilvia; Kovács, Béla

    2016-11-01

    Several studies have demonstrated that selenium (Se) at low concentrations is beneficial, whereas high Se concentrations can induce toxicity. Controlling Se uptake, metabolism, translocation and accumulation in plants is important to decrease potential health risks and helping to select proper biofortification methods to improve the nutritional content of plant-based foods. The uptake and distribution of Se, changes in Se content, and effects of various concentrations of Se in two forms (sodium selenite and sodium selenate) on sunflower and maize plants were measured in nutrient solution experiments. Results revealed the Se content in shoots and roots of both sunflower and maize plants significantly increased as the Se level increased. In this study, the highest exposure concentrations (30 and 90 mg/L, respectively) caused toxicity in both sunflower and maize. While both Se forms damaged and inhibited plant growth, each behaved differently, as toxicity due to selenite was observed more than in the selenate treatments. Sunflower demonstrated a high Se accumulation capacity, with higher translocation of selenate from roots to shoots compared with selenite. Since in seleniferous soils, a high change in plants' capability exists to uptake Se from these soils and also most of the cultivated crop plants have a bit tolerance to high Se levels, distinction of plants with different Se tolerance is important. This study has tried to discuss about it.

  13. Neutron activation analysis applied to the determination of selenium in bovine plasma

    International Nuclear Information System (INIS)

    Hevia, Sonia E.; Resnizky, Sara M.; Gil, Susana B.; Pawlak, Eva

    1999-01-01

    The procedure used to determine selenium in bovine plasma by neutron irradiation of the samples, followed by a radiochemical separation, is described. This procedure allows the direct determination of the value of the selenium plasmatic level, instead of the indirect conventional method that determines the blood glutathion peroxidase enzyme, as an indicator of the selenium content in the blood. (author)

  14. 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.

  15. Biofortification and phytoremediation of selenium in China

    Directory of Open Access Journals (Sweden)

    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.

  16. Selenium status in soil, water and essential crops of Iran

    Directory of Open Access Journals (Sweden)

    Nazemi Lyly

    2012-11-01

    Full Text Available Abstracts As a contributing factor to health, the trace element selenium (Se is an essential nutrient of special interest for humans and all animals. It is estimated that 0.5 to 1 billion people worldwide suffer from Se deficiency. In spite of the important role of Se, its concentrations in soil, water and essential crops have not been studied in Iran. Therefore, the main aim of the current study was to determine the Se content of soil, water, and essential crops (rice in North, wheat in Center, date, and pistachio in South of different regions of Iran. Sampling was performed in the North, South, and Central regions of Iran. In each selected area in the three regions, 17 samples of surface soil were collected; samples of water and essential crops were also collected at the same sampling points. Upon preliminary preparation of all samples, the Se concentrations were measured by ICP-OES Model Varian Vista-MPX. The amount of soil-Se was found to be in the range between 0.04 and 0.45 ppm in the studied areas; the Se content of soil in the central region of Iran was the highest compared to other regions (p

  17. The Effect of Indium Content on the Atomic Environment and Cluster Stability of GeSe4Inx=10,15 Glasses

    Directory of Open Access Journals (Sweden)

    Georgios S. E. Antipas

    2015-01-01

    Full Text Available The atomic environments of two chalcogenide glasses, with compositions GeSe4In10 and GeSe4In15, were studied via Reverse Monte Carlo and Density Functional Theory. Indium content demoted Ge–Se bonding in favor of Se-In while the contribution of Se–Se in the first coordination shell order was faint. Upon transition to the richer In glass, there was formation of rich Ge-centered clusters at radial distances further than 4 Å from the RMC box center, which was taken to signify a reduction of Ge–Se interactions. Cluster coordination by Se promoted stability while, very conclusively, In coordination lowered cluster stability by intervening in the Ge–Se and Se–Se networks.

  18. Spectrophotometric evaluation of selenium binding by Saccharomyces cerevisiae ATCC MYA-2200 and Candida utilis ATCC 9950 yeast.

    Science.gov (United States)

    Kieliszek, Marek; Błażejak, Stanisław; Płaczek, Maciej

    2016-05-01

    In this study, the ability of selenium binding the biomas of Saccharomyces cerevisiae ATCC MYA-2200 and Candida utilis ATCC 9950 was investigated. Sodium selenite(IV) salts were added to the experimental media at concentrations of 10, 20, 40, and 60 mg Se(4+) L(-1). In the tested concentration range, one concentration reported a significant reduction in the biomass yield of both yeast strains. Intense growth was observed for C. utilis yeast, which reached the highest biomass yield of 15 gd.w.L(-1) after 24h cultivation in the presence of 10mg Se(4+) L(-1). Based on the use of spectrophotometric method for the determination of selenium content by using Variamine Blue as a chromogenic agent, efficient accumulation of this element in the biomass of the investigated yeast was observed. The highest amount of selenium, that is, 5.64 mg Se(4+)gd.w.(-1), was bound from the environment by S. cerevisiae ATCC MYA-2200 cultured in the presence of 60 mg Se(4+) L(-1) medium 72h Slightly less amount, 5.47 mg Se(4+) gd.w.(-1), was absorbed by C. utilis ATCC 9950 during similar cultural conditions. Based on the results of the biomass yield and the use of selenium from the medium, it can be observed that yeasts of the genus Candida are more efficient in binding this element, and this property finds practical application in the production of selenium-enriched yeast. Copyright © 2016 Elsevier GmbH. All rights reserved.

  19. Study On Selenium Accumulation In Turkey Tail Fungus (Trametes Versicolor) By Using Instrumental Neutron Activation Analysis

    International Nuclear Information System (INIS)

    Le Xuam Tham; Ho Van Hai; Bui Thi Minh Hai; Nguyen Giang; Nguyen Thi Dieu Hanh

    2008-01-01

    Medicinal mushroom Kawaratake Trametes versicolor strain obtained from Chiba University, Japan, was fermented at stationary Erlenmayer flasks 250 ml, containing PG media with Se (10 ppm as selenate) and without Se (control) supplement, incubated at 32-34 o C (room temperature in Ho Chi Minh City). Selenium was added as dissolve selenate Na 2 SeO 4 , in which Se was enriched with 74 Se. Under neutron fluxes in nuclear reactor 74 Se will be activated into 75 Se emitted gamma rays (n-γ reaction), recorded for calculations of Se contents in the samples. Cultivation of Kawaratake on mixed substrates based sawdusts supplemented with Se by injecting directly into center region of the substrate based on rubber tree sawdust. Analysis of Se contents in fungal biomass harvested by using INAA with neutron flux at 10 12 cm -2 .s -1 in Nuclear Reactor at Dalat City, Vietnam. The results obtained with Trametes versicolor showed Se levels in mycelial biomass up to 600-1500 ppm, while in the control (without Se supplement), only trace of Se (1 ppm more or less) was found. It would be related to the researches on configurations of complex of polysaccharides and proteins in biomass with high bioactivities. Se would substitute S for some due structures and enhance their antioxydant activities. (author)

  20. The role of selenium in predicting preeclampsia

    Directory of Open Access Journals (Sweden)

    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.

  1. Selenium and tellurium nanomaterials

    Science.gov (United States)

    Piacenza, Elena; Presentato, Alessandro; Zonaro, Emanuele; Lampis, Silvia; Vallini, Giovanni; Turner, Raymond J.

    2018-04-01

    Over the last 40 years, the rapid and exponential growth of nanotechnology led to the development of various synthesis methodologies to generate nanomaterials different in size, shape and composition to be applied in various fields. In particular, nanostructures composed of Selenium (Se) or Tellurium (Te) have attracted increasing interest, due to their intermediate nature between metallic and non-metallic elements, being defined as metalloids. Indeed, this key shared feature of Se and Te allows us the use of their compounds in a variety of applications fields, such as for manufacturing photocells, photographic exposure meters, piezoelectric devices, and thermoelectric materials, to name a few. Considering also that the chemical-physical properties of elements result to be much more emphasized when they are assembled at the nanoscale range, huge efforts have been made to develop highly effective synthesis methods to generate Se- or Te-nanomaterials. In this context, the present book chapter will explore the most used chemical and/or physical methods exploited to generate different morphologies of metalloid-nanostructures, focusing also the attention on the major advantages, drawbacks as well as the safety related to these synthetic procedures.

  2. Selenium bioavailability from soy protein isolate and tofu in rats fed a torula yeast-based diet.

    Science.gov (United States)

    Yan, Lin; Graef, George L; Reeves, Philip G; Johnson, LuAnn K

    2009-12-23

    Selenium (Se) is an essential nutrient, and soy is a major plant source of dietary protein to humans. The United States produces one-third of the world's soybeans, and the Se-rich Northern Plains produce a large share of the nation's soybeans. The present study used a rat model to determine the bioavailability of Se from a protein isolate and tofu (bean curd) prepared from a soybean cultivar we recently developed specifically for food grade markets. The soybean seeds contained 2.91 mg Se/kg. Male Sprague-Dawley rats were depleted of Se by feeding them a 30% Torula yeast-based diet containing 5 microg Se/kg; after 56 days, they were replenished of Se for an additional 50 days by feeding them the same diet supplemented with 20, 30, or 40 microg Se/kg from soy protein isolate or tofu. l-Selenomethionine (SeMet) was used as a reference. Selenium bioavailability was determined on the basis of the responses of Se-dependent enzyme activities and tissue Se contents, comparing those responses for each soy product to those for SeMet using a slope-ratio method. Dietary supplementation with the protein isolate or tofu resulted in dose-dependent increases in glutathione peroxidase activities in blood and liver and thioredoxin reductase activity in liver, as well as dose-dependent increases in the Se contents of plasma, liver, muscle, and kidneys. These responses indicated an overall bioavailability of approximately 97% for Se from both the protein isolate and tofu, relative to SeMet. These results demonstrate that Se from this soybean cultivar is highly bioavailable in this model and that high-Se soybeans can be good dietary sources of Se.

  3. 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...

  4. 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,...

  5. Copper and selenium supplementation of ewes grazing on pastures ...

    African Journals Online (AJOL)

    ,09 pg Se/g DM, het bloedseleniumkonsentrasiesvaono ie verhoog, maar het min invloed op die lewer- en nierseleniumkonsentrasievsa n lammers kort na geboorte gehad. Keywords: Blood selenium, copper supplementiation, fertility, plasma ...

  6. 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)

  7. 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.

  8. 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.)

  9. The fascinating facets of plant selenium accumulation - biochemistry, physiology, evolution and ecology.

    Science.gov (United States)

    Schiavon, Michela; Pilon-Smits, Elizabeth A H

    2017-03-01

    Contents 1582 I. 1582 II. 1583 III. 1588 IV. 1590 V. 1592 1592 References 1592 SUMMARY: The importance of selenium (Se) for medicine, industry and the environment is increasingly apparent. Se is essential for many species, including humans, but toxic at elevated concentrations. Plant Se accumulation and volatilization may be applied in crop biofortification and phytoremediation. Topics covered here include beneficial and toxic effects of Se on plants, mechanisms of Se accumulation and tolerance in plants and algae, Se hyperaccumulation, and ecological and evolutionary aspects of these processes. Plant species differ in the concentration and forms of Se accumulated, Se partitioning at the whole-plant and tissue levels, and the capacity to distinguish Se from sulfur. Mechanisms of Se hyperaccumulation and its adaptive significance appear to involve constitutive up-regulation of sulfate/selenate uptake and assimilation, associated with elevated concentrations of defense-related hormones. Hyperaccumulation has evolved independently in at least three plant families, probably as an elemental defense mechanism and perhaps mediating elemental allelopathy. Elevated plant Se protects plants from generalist herbivores and pathogens, but also gives rise to the evolution of Se-resistant specialists. Plant Se accumulation affects ecological interactions with herbivores, pollinators, neighboring plants, and microbes. Hyperaccumulation tends to negatively affect Se-sensitive ecological partners while facilitating Se-resistant partners, potentially affecting species composition and Se cycling in seleniferous ecosystems. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

  10. Antitumor Effect of Selenium and Modified Pectin Nano Particles and Gamma Radiation on Ehrilch Solid Tumor in Female Mice

    International Nuclear Information System (INIS)

    Mansour, S. Z.; Anis, L.M.; EI- Batal, A.I.

    2010-01-01

    Selenium nano particle (Nano- Se) is a novel Se species with novel biological activities with low toxicity. The aim of the present work was to evaluate the antitumor activity of a novel Nano- Se compound with or without gamma irradiation of female mice. Selenium size- controlled Nano-Se was prepared by a simple method by adding modified pectin to the selenious acid and ascorbic acid. The antitumor activity of Selenium and Modified Pectin Nano Particles (Se-Mp- NPs) were evaluated against Ehrilch ascites carcinoma (In vitro) and Ehrilch solid tumor model (In vivo). The antioxidant states of the novel compound were assessed measuring parameters in blood and tumor tissue of female mice. Malonaldehydoyl (MDA) end product of lipid peroxidation was evaluated in plasma and tumor tissue. Glutathione -S- transferase (GST) and cytochrome P450 (Cyto P450) were determined in tumor tissue homogenate. Tumor necrosis factor alpha (TNF- a) concentration and interleukin 10 (IL- 10) concentrations was evaluated in plasma of female mice. The effect of tumor inoculation and different treatments on liver enzymes (ALT and AST) and kidney Function (urea and creatinine) were detected in the plasma of animals. Apoptosis was shown and estimated in tumor tissue of animals histopathological of tumor in different groups of mice were examined. Ehrilch solid tumor induced a significant increase in MDA content, GSH-Px and GST activities level and in the amount of metabolites of CYP 450. Moreover, a significant decrease was observed in GSH content, SOD activity level in the tumor tissue, INF- a concentration, IL- 10 concentration in the plasma. Also, a significant alteration in kidney and liver functions was occurred as compared to control group. The results showed a significant antitumor activity of selenium and Modified Pectin Nano Particles (Se-Mp- NPs) at the concentration 2.25 μg / ml was 70%

  11. Speciation of selenium dietary supplements; formation of S-(methylseleno)cysteine and other selenium compounds

    International Nuclear Information System (INIS)

    Amoako, Prince O.; Uden, Peter C.; Tyson, Julian F.

    2009-01-01

    Speciation of selenium is of interest because it is both essential and toxic to humans, depending on the species and the amount ingested. Following indications that selenium supplementation could reduce the incidence of some cancers, selenium-enriched yeast and other materials have been commercialized as supplements. Most dramatically however, the SELECT trial that utilized L-selenomethionine as the active supplement was terminated in 2008 and there is much debate regarding both the planning and the results of efficacy studies. Further, since dietary supplements are not regulated as pharmaceuticals, there are concerns about the quality, storage conditions, stability and selenium content in selenium supplements. Enzymatic hydrolysis enabled selenium speciation profiles to be obtained by high performance liquid chromatography with inductively coupled plasma mass spectrometry (HPLC-ICP-MS) and following derivatization gas chromatography with atomic emission detection (GC-AED). Coated fiber solid phase microextraction (SPME) was used to extract volatile selenium species for determination by GC-AED and GC-MS. Similar speciation patterns were observed between yeast-based supplements subject to extended storage and those heated briefly at elevated temperatures. All the yeast-based supplements and one yeast-free supplement formed S-(methylseleno)cysteine on heating. Evidence was obtained in support of the hypotheses that S-(methylseleno)cysteine is formed from a reaction between dimethyldiselenide and cysteine or cystine.

  12. 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.

  13. 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

  14. Relationship of dietary intake of fish and non-fish selenium to serum lipids in Japanese rural coastal community.

    Science.gov (United States)

    Miyazaki, Yukiko; Koyama, Hiroshi; Nojiri, Masami; Suzuki, Shosuke

    2002-01-01

    Several studies have suggested that dietary selenium deficiency may be associated with an increased risk of coronary heart disease (CHD). In the present study, 55 men and 71 women were selected from participants in a health examination in a rural coastal community in Japan. The mean dietary selenium intake calculated from the simple food frequency questionnaire (SFFQ) was 127.5 micrograms/day. Fish was the major source of dietary selenium and it contributed to 68.7% of the daily total. HDL cholesterol was higher in the middle selenium intake group and in the high selenium intake group than in the low selenium intake group in all subjects and for males, and a significant difference was found between the middle selenium intake group and the low selenium intake group. The atherogenic index was significantly higher in the low selenium intake group than in the middle selenium intake group and in the high selenium intake group in males. GPx activity, total cholesterol and triacylglycerols did not show any significant differences among the three different selenium intake groups. Dietary intake of non-fish Se had a positive correlation with HDL cholesterol, and an inverse correlation with the atherogenic index in all subjects and for females. On the other hand, dietary intake of fish-Se had no relationship with any serum lipids. Non-fish Se is an important factor in selenium status for the prevention of CHD.

  15. 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.

  16. Reduced Utilization of Selenium by Naked Mole Rats Due to a Specific Defect in GPx1 Expression*

    Science.gov (United States)

    Kasaikina, Marina V.; Lobanov, Alexei V.; Malinouski, Mikalai Y.; Lee, Byung Cheon; Seravalli, Javier; Fomenko, Dmitri E.; Turanov, Anton A.; Finney, Lydia; Vogt, Stefan; Park, Thomas J.; Miller, Richard A.; Hatfield, Dolph L.; Gladyshev, Vadim N.

    2011-01-01

    Naked mole rat (MR) Heterocephalus glaber is a rodent model of delayed aging because of its unusually long life span (>28 years). It is also not known to develop cancer. In the current work, tissue imaging by x-ray fluorescence microscopy and direct analyses of trace elements revealed low levels of selenium in the MR liver and kidney, whereas MR and mouse brains had similar selenium levels. This effect was not explained by uniform selenium deficiency because methionine sulfoxide reductase activities were similar in mice and MR. However, glutathione peroxidase activity was an order of magnitude lower in MR liver and kidney than in mouse tissues. In addition, metabolic labeling of MR cells with 75Se revealed a loss of the abundant glutathione peroxidase 1 (GPx1) band, whereas other selenoproteins were preserved. To characterize the MR selenoproteome, we sequenced its liver transcriptome. Gene reconstruction revealed standard selenoprotein sequences except for GPx1, which had an early stop codon, and SelP, which had low selenocysteine content. When expressed in HEK 293 cells, MR GPx1 was present in low levels, and its expression could be rescued neither by removing the early stop codon nor by replacing its SECIS element. In addition, GPx1 mRNA was present in lower levels in MR liver than in mouse liver. To determine if GPx1 deficiency could account for the reduced selenium content, we analyzed GPx1 knock-out mice and found reduced selenium levels in their livers and kidneys. Thus, MR is characterized by the reduced utilization of selenium due to a specific defect in GPx1 expression. PMID:21372135

  17. Selenium deficiency-induced alterations in ion profiles in chicken muscle.

    Directory of Open Access Journals (Sweden)

    Haidong Yao

    Full Text Available Ion homeostasis plays important roles in development of metabolic diseases. In the present study, we examined the contents and distributions of 25 ions in chicken muscles following treatment with selenium (Se deficiency for 25 days. The results revealed that in chicken muscles, the top ranked microelements were silicon (Si, iron (Fe, zinc (Zn, aluminum (Al, copper (Cu and boron (B, showing low contents that varied from 292.89 ppb to 100.27 ppm. After Se deficiency treatment, essential microelements [Cu, chromium (Cr, vanadium (V and manganese (Mn], and toxic microelements [cadmium (Cd and mercury (Hg] became more concentrated (P < 0.05. Elements distribution images showed generalized accumulation of barium (Ba, cobalt (Co, Cu, Fe and V, while Cr, Mn, and Zn showed pin point accumulations in muscle sections. Thus, the ion profiles were generally influenced by Se deficiency, which suggested a possible role of Se deficiency in muscle dysfunctions caused by these altered ion profiles.

  18. 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

  19. 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)

  20. 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...

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

    DEFF Research Database (Denmark)

    Larsen, Erik Huusfeldt; Lobinski, R.; Burger-Meyer, K.

    2006-01-01

    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...... 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(-1) (dry mass). Fertilisation with selenate and addition of mycorrhiza strongly increased the selenium content...... 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...

  2. Impact of selenium enrichment on seed potato tubers

    Directory of Open Access Journals (Sweden)

    M. TURAKAINEN

    2008-12-01

    Full Text Available The aim of this study was to investigate the effect of Se enrichment on the growth of sprouts and growth vigour of seed potatoes (Solanum tuberosum L. stored for 2 to 8 months. Our results showed that Se did not affect the duration of dormancy. At the high addition levels (0.075 and 0.9 mg kg-1 quartz sand, Se had some positive effects on the growth of sprouts. The peak sprouting capacity was reached after 8 months of storage. The highest Se enrichment of tubers had some positive effect on the free putrescine content in sprouts. However, the better growth of sprouts was not consistent with the growth vigour of the seed tubers and yield produced. Selenium had no significant effect on the malondialdehyde (MDA or on the concentration of soluble sugars and starch. No significant effect of added Se on the early growth, stem and tuber numbers and yield parameters was observed. Irrespective of the level of Se added, the highest yield was harvested from plants produced with seed tubers stored for 6 months. Our results indicate that Se had some positive effects on the growth of sprouts, but it had no consistent effect on the growth vigour of seed tubers.;

  3. A crystallization study of amorphous Tex(Bi2Se3)1-x alloys with variation of the Se content

    International Nuclear Information System (INIS)

    Saxena, Manish

    2005-01-01

    Alloys of the Te x (Bi 2 Se 3 ) 1-x glass system, obtained using rapid quenching technique, have been characterized by calorimetric measurements and differential thermal analysis for different heating rates in this work. A systematic investigation of crystallization kinetics is carried out for the composition range in which amorphous alloys exhibit a large glass-forming ability in Se-based systems, thermal stability including in the temperature range between the glass transition temperature, T g , and crystallization temperature, T c , and the effect of ΔT c (=T c - T g ) at different heating rates for the formation of an amorphous single phase is evaluated from thermal analytical data. The thermal stability of these glasses is found to provide good control for forming these glasses with ease. This analysis helps to find the suitability of an alloy for use in phase transition optical memories/switches

  4. Controls on selenium distribution and mobilization in an irrigated shallow groundwater system underlain by Mancos Shale, Uncompahgre River Basin, Colorado, USA

    Energy Technology Data Exchange (ETDEWEB)

    Mills, Taylor J.; Mast, M. Alisa; Thomas, Judith; Keith, Gabrielle

    2016-10-01

    Elevated selenium (Se) concentrations in surface water and groundwater have become a concern in areas of the Western United States due to the deleterious effects of Se on aquatic ecosystems. Elevated Se concentrations are most prevalent in irrigated alluvial valleys underlain by Se-bearing marine shales where Se can be leached from geologic materials into the shallow groundwater and surface water systems. This study presents groundwater chemistry and solid-phase geochemical data from the Uncompahgre River Basin in Western Colorado, an irrigated alluvial landscape underlain by Se-rich Cretaceous marine shale. We analyzed Se species, major and trace elements, and stable nitrogen and oxygen isotopes of nitrate in groundwater and aquifer sediments to examine processes governing selenium release and transport in the shallow groundwater system. Groundwater Se concentrations ranged from below detection limit (< 0.5 μg L{sup −1}) to 4070 μg L{sup −1}, and primarily are controlled by high groundwater nitrate concentrations that maintain oxidizing conditions in the aquifer despite low dissolved oxygen concentrations. High nitrate concentrations in non-irrigated soils and nitrate isotopes indicate nitrate is largely derived from natural sources in the Mancos Shale and alluvial material. Thus, in contrast to areas that receive substantial NO{sub 3} inputs through inorganic fertilizer application, Se mitigation efforts that involve limiting NO{sub 3} application might have little impact on groundwater Se concentrations in the study area. Soluble salts are the primary source of Se to the groundwater system in the study area at-present, but they constitute a small percentage of the total Se content of core material. Sequential extraction results indicate insoluble Se is likely composed of reduced Se in recalcitrant organic matter or discrete selenide phases. Oxidation of reduced Se species that constitute the majority of the Se pool in the study area could be a potential

  5. Natural variation of selenium in Brazil nuts and soils from the Amazon region.

    Science.gov (United States)

    Silva Junior, E C; Wadt, L H O; Silva, K E; Lima, R M B; Batista, K D; Guedes, M C; Carvalho, G S; Carvalho, T S; Reis, A R; Lopes, G; Guilherme, L R G

    2017-12-01

    Brazil nut tree (Bertholletia excelsa) is native of the Amazon rainforest. Brazil nuts are consumed worldwide and are known as the richest food source of selenium (Se). Yet, the reasoning for such Se contents is not well stablished. We evaluated the variation in Se concentration of Brazil nuts from Brazilian Amazon basin, as well as soil properties, including total Se concentration, of the soils sampled directly underneath the trees crown, aiming to investigate which soil properties influence Se accumulation in the nuts. The median Se concentration in Brazil nuts varied from 2.07 mg kg - 1 (in Mato Grosso state) to 68.15 mg kg - 1 (in Amazonas state). Therefore, depending on its origin, a single Brazil nut could provide from 11% (in the Mato Grosso state) up to 288% (in the Amazonas state) of the daily Se requirement for an adult man (70 μg). The total Se concentration in the soil also varied considerably, ranging from Brazil nuts generally increased in soils with higher total Se content, but decreased under acidic conditions in the soil. This indicates that, besides total soil Se concentration, soil acidity plays a major role in Se uptake by Brazil nut trees, possibly due to the importance of this soil property to Se retention in the soil. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

    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.

  7. Evaluation of genotypic variation of broccoli (Brassica oleracea var. italic) in response to selenium treatment.

    Science.gov (United States)

    Ramos, Silvio J; Yuan, Youxi; Faquin, Valdemar; Guilherme, Luiz Roberto G; Li, Li

    2011-04-27

    Broccoli (Brassica oleracea var. italic) fortified with selenium (Se) has been promoted as a functional food. Here, we evaluated 38 broccoli accessions for their capacity to accumulate Se and for their responses to selenate treatment in terms of nutritional qualities and sulfur gene expresion. We found that the total Se content varied with over 2-fold difference among the leaf tissues of broccoli accessions when the plants were treated with 20 μM Na(2)SeO(4). Approximately half of total Se accumulated in leaves was Se-methylselenocysteine and selenomethionine. Transcriptional regulation of adenosine 5'-phosphosulfate sulfurylase and selenocysteine Se-methyltransferase gene expression might contribute to the different levels of Se accumulation in broccoli. Total glucosinolate contents were not affected by the concentration of selenate application for the majority of broccoli accessions. Essential micronutrients (i.e., Fe, Zn, Cu, and Mn) remained unchanged among half of the germplasm. Moreover, the total antioxidant capacity was greatly stimulated by selenate in over half of the accessions. The diverse genotypic variation in Se, glucosinolate, and antioxidant contents among accessions provides the opportunity to breed broccoli cultivars that simultaneously accumulate Se and other health benefit compounds.

  8. 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

  9. Mechanisms of Selenium Enrichment and Measurement in Brassicaceous Vegetables, and Their Application to Human Health

    Directory of Open Access Journals (Sweden)

    Melanie Wiesner-Reinhold

    2017-08-01

    Full Text Available Selenium (Se is an essential micronutrient for human health. Se deficiency affects hundreds of millions of people worldwide, particularly in developing countries, and there is increasing awareness that suboptimal supply of Se can also negatively affect human health. Selenium enters the diet primarily through the ingestion of plant and animal products. Although, plants are not dependent on Se they take it up from the soil through the sulphur (S uptake and assimilation pathways. Therefore, geographic differences in the availability of soil Se and agricultural practices have a profound influence on the Se content of many foods, and there are increasing efforts to biofortify crop plants with Se. Plants from the Brassicales are of particular interest as they accumulate and synthesize Se into forms with additional health benefits, such as methylselenocysteine (MeSeCys. The Brassicaceae are also well-known to produce the glucosinolates; S-containing compounds with demonstrated human health value. Furthermore, the recent discovery of the selenoglucosinolates in the Brassicaceae raises questions regarding their potential bioefficacy. In this review we focus on Se uptake and metabolism in the Brassicaceae in the context of human health, particularly cancer prevention and immunity. We investigate the close relationship between Se and S metabolism in this plant family, with particular emphasis on the selenoglucosinolates, and consider the methodologies available for identifying and quantifying further novel Se-containing compounds in plants. Finally, we summarize the research of multiple groups investigating biofortification of the Brassicaceae and discuss which approaches might be most successful for supplying Se deficient populations in the future.

  10. Effects of Fermented Mushroom of Cordyceps sinensis, Rich in Selenium, on Uterine Cervix Cancer

    Directory of Open Access Journals (Sweden)

    Jing Ji

    2014-01-01

    Full Text Available The purpose of this study was to investigate the effect of fermented mushroom of Cordyceps sinensis (CS, rich in selenium (Se-CS, on uterine cervical cancer in mice. The methylcholanthrene- (MCA- induced tumor model was used in this paper. After the mice were administered Se-CS, the animals showed 40% tumor incidence (P<0.05. Se-CS also enhanced the immune functions. Se-CS treatment showed significant (P<0.05–0.01 restoration in the level of glutathione content, lipid peroxidation, glutathione peroxidase activity, glutathione reductase activity, catalase activity, Na+/K+-ATPase activity, and glutathione S transferase activity. This finding suggested that the concomitant use of Se and CS could be a potential therapeutic approach to improve the efficacy of therapy for uterine cervical cancer.

  11. Selenium in diet

    Science.gov (United States)

    ... how much of the mineral was in the soil where the plants grew. Brazil nuts are a very good source of selenium. Fish, shellfish , red meat, grains, eggs, chicken, liver, and garlic ... soil have higher levels of selenium. Brewer's yeast, wheat ...

  12. 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

  13. 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

  14. 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.

  15. 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...

  16. 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.

  17. 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.

  18. Assessment of the anticancer compounds Se-methylselenocysteine and glucosinolates in Se-biofortified broccoli (Brassica oleracea L. var. italica) sprouts and florets.

    Science.gov (United States)

    Ávila, Fabricio William; Faquin, Valdemar; Yang, Yong; Ramos, Silvio Junio; Guilherme, Luiz Roberto G; Thannhauser, Theodore W; Li, Li

    2013-07-03

    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 compounds Se-methylselenocysteine (SeMSCys) and glucosinolates in broccoli sprouts and florets. Total Se and SeMSCys content in sprouts increased concomitantly with increasing Se doses. Selenate was superior to selenite in inducing total Se accumulation, but selenite is equally effective as selenate in promoting SeMSCys synthesis in sprouts. Increasing sulfur doses reduced total Se and SeMSCys content in sprouts treated with selenate, but not in those with selenite. Examination of five broccoli cultivars reveals that sprouts generally have better fractional ability than florets to convert inorganic Se into SeMSCys. Distinctive glucosinolate profiles between sprouts and florets were observed, and sprouts contained approximately 6-fold more glucoraphanin than florets. In contrast to florets, glucosinolate content was not affected by Se treatment in sprouts. Thus, Se-enriched broccoli sprouts are excellent for simultaneous accumulation of chemopreventive compounds SeMSCys and glucoraphanin.

  19. Study of selenocompounds from selenium-enriched culture of edible sprouts.

    Science.gov (United States)

    Funes-Collado, Virginia; Morell-Garcia, Albert; Rubio, Roser; López-Sánchez, José Fermín

    2013-12-15

    Selenium is recognised as an essential micronutrient for humans and animals. One of the main sources of selenocompounds in the human diet is vegetables. Therefore, this study deals with the Se species present in different edible sprouts grown in Se-enriched media. We grew alfalfa, lentil and soy in a hydroponic system amended with soluble salts, containing the same proportion of Se, in the form of Se(VI) and Se(IV). Total Se in the sprouts was determined by acidic digestion in a microwave system and by ICP/MS. Se speciation was carried out by enzymatic extraction (Protease XIV) and measured by LC-ICP/MS. The study shows that the Se content of plants depends on the content in the growth culture, and that part of the inorganic Se was biotransformed mainly into SeMet. These results contribute to our understanding of the uptake of inorganic Se and its biotransformation by edible plants. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Dietary Selenium and Human Health

    Directory of Open Access Journals (Sweden)

    Lutz Schomburg

    2016-12-01

    Full Text Available Next year (2017, the micronutrient Selenium (Se is celebrating its birthday—i.e., 200 years after first being identified by the Swedish chemist Jöns Jakob Berzelius. Despite its impressive age, research into the functions of this essential trace element is very alive and reaching out for new horizons. This special issue presents some recent fascinating, exciting, and promising developments in Se research in the form of eight original contributions and seven review articles. Collectively, aspects of Se supply, biochemical, physiological, and chemotherapeutic effects, and geobiological interactions are covered by leading scientists in the areas of nutritional, basic, and clinical research. It is obvious from the contributions that the bicentennial anniversary will celebrate a micronutrient still in its infancy with respect to being understood in terms of its biomedical importance.

  1. 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

  2. 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...

  3. 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.

  4. 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...

  5. Selenium for preventing cancer

    Directory of Open Access Journals (Sweden)

    Gabriele Dennert

    Full Text Available BACKGROUND: Selenium is a trace element essential to humans. Higher selenium exposure and selenium supplements have been suggested to protect against several types of cancers. OBJECTIVE: Two research questions were addressed in this review: What is the evidence for: 1. an aetiological relationship between selenium exposure and cancer risk in women and men?; 2. the efficacy of selenium supplementation for cancer prevention in women and men? SEARCH STRATEGY: We searched electronic databases and bibliographies of reviews and included publications. SELECTION CRITERIA: We included prospective observational studies to answer research question (a and randomised controlled trials (RCTs to answer research question (b. DATA COLLECTION AND ANALYSIS: We conducted random effects meta-analyses of epidemiological data when five or more studies were retrieved for a specific outcome. We made a narrative summary of data from RCTs. MAIN RESULTS: We included 49 prospective observational studies and six RCTs. In epidemiologic data, we found a reduced cancer incidence (summary odds ratio, OR, 0.69; 95% confidence interval, CI, 0.53 to 0.91 and mortality (OR 0.55, 95% CI 0.36 to 0.83 with higher selenium exposure. Cancer risk was more pronouncedly reduced in men (incidence: OR 0.66, 95% CI 0.42 to 1.05 than in women (incidence: OR 0.90, 95% CI 0.45 to 1.77. These findings have potential limitations due to study design, quality and heterogeneity of the data, which complicated the interpretation of the summary statistics. The RCTs found no protective efficacy of selenium yeast supplementation against non-melanoma skin cancer or L-selenomethionine supplementation against prostate cancer. Study results for the prevention of liver cancer with selenium supplements were inconsistent and studies had an unclear risk of bias. The results of the Nutritional Prevention of Cancer Trial (NPCT and SELECT raised concerns about possible harmful effects of selenium supplements. AUTHORS

  6. 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 ...

  7. 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.

  8. Luminescence investigation of Cu(In,Ga)Se{sub 2}solar cells with different Ga-contents grown in a three-stage-process on glass substrate

    Energy Technology Data Exchange (ETDEWEB)

    Wendt, Kristin; Mueller, Mathias; Hempel, Thomas; Bertram, Frank; Christen, Juergen [Institute of Experimental Physics, Otto-von-Guericke-University Magdeburg (Germany); Abou-Ras, Daniel; Rissom, Thorsten; Unold, Thomas; Schock, Hans-Werner [Helmholtz-Zentrum Berlin for Materials and Energy (Germany)

    2011-07-01

    A fundamental advantage of Cu(In,Ga)Se{sub 2} (CIGS) alloys as absorber materials in thin-film solar cells is their direct band gap energies which can be varied between 1.04 eV (CuInSe{sub 2}) and 1.68 eV (CuGaSe{sub 2}). Photoluminescence (PL) spectra of complete CIGS solar cells with a systematic variation of the Ga-content in the absorber layer will be presented. The CIGS cells investigated were grown on a Mo back contact sputtered on soda lime glass and have a Ga-concentration ranging over the entire range from CuInSe{sub 2} to CuGaSe{sub 2}. Samples with Ga-contents between 100 % and 33 % show two broad luminescence bands. In contrast, CuInSe{sub 2} exhibits only one broad luminescence band. Each band is composed of two or three different transitions. Varying excitation density over four orders of magnitude results for samples with Ga-content of 0 % and 33 % in a blueshift of the main peak with increasing excitation density. For higher Ga-concentrations, first a blue- and then a redshift of the dominating peak with increasing excitation density is visible. The temperature dependence of the PL spectra is investigated going from 4 K to 300 K.

  9. 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...

  10. Selenium accumulation in the cockle Anadara trapezia

    International Nuclear Information System (INIS)

    Jolley, Dianne F.; Maher, William A.; Kyd, Jennelle

    2004-01-01

    An extensive study on Se accumulation in a population of Anadara trapezia from a marine lake is reported. The effects of organism mass, gender, reproductive cycle, and season on Se accumulation and tissue distribution were investigated. Analyses showed that gender and reproductive cycle had no significant effect on Se accumulation. A. trapezia showed a strong positive correlation between Se burden and tissue mass. Constant Se concentrations were observed within individual populations but varied spatially with sediment Se concentrations. Se concentrations in tissues decreased from gills > gonad/intestine > mantle > muscle > foot, which remained constant over 12 months, however, significantly lower concentrations were observed in the summer compared to winter. A. trapezia is a good biomonitor for Se, as gender and size do not effect concentration, however, season of collection must be reported if changes in Se bioavailability are to be identified in short term studies, or during intersite comparisons. - Capsule: The marine bivalve Anadara trapezia is a good bioindicator for marine selenium contamination

  11. 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.

  12. 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.

  13. The organic selenium identification on the cattle feedstuffs in Sumedang region

    International Nuclear Information System (INIS)

    Endang Yuni Setyowati; Ujang Hidayat Tanuwiria; Muhayatun Santoso

    2010-01-01

    Selenium is an essential micro mineral which has an important role in cattle growth. Feeding cattle with this mineral increase feed efficiency and decrease oxidative stress that results in lengthening cattle product shelf live. Se deficiency reduce cattle resistance to infection disease and growth rate. Feeding cattle with variety feedstuffs is necessary in order to balance its nutrient requirement. Se content within feedstuffs is varying and depends on the Se content and the condition of soil. Sumedang is a potential region for cattle production as it has variety plants for cattle feed. However, there is no information on the Se content of feedstuffs since it has not been identified yet. This research was aim to identify Se content of several feedstuffs, that were grass, cassava pumice and chips, coconut meal, soya sauce waste, rice brand and wheat pollard. Samples were identified by Neutron Activation Analysis (NAA). There was no Se detection on the grass and rice brand. Se on soya sauce waste is vary from 0.25-0.45 mg/kg; on coconut meat is vary between 0.23-0.44 mg/kg; on cassava chips is 0.18 mg/kg; on cassava pumice is between 0.32-0.40 mg/kg and that on wheat pollard is between 0.18-0.35 mg/kg. Se content on the ration that mixed from all feedstuffs is 0.279 mg/kg. Supplementation organic Se 0.3 ppm on the ration increases the Se content to 0.608 mg/kg. It could expect that Se supplementation to the ration would result in rising cattle production. (author)

  14. Blood Selenium Associated with Health and Fertility in Norwegian Dairy Herds

    Directory of Open Access Journals (Sweden)

    Kommisrud E

    2006-12-01

    Full Text Available A survey of blood selenium (Se concentrations in Norwegian Red heifers and dry period cows was conducted to reveal possible association to management, feeding, health and fertility. Selenium contents were determined in 254 herd blood samples consisting of pooled samples from individual non-lactating animals from herds in 5 counties. The Se concentrations showed a normal distribution with mean 0.09 μg Se/g blood, with a standard deviation (SD of 0.05, and ranged from 0.02 to 0.23 μg/g, with 50 % of the samples being between 0.06 and 0.11 μg/g. The herds with Se concentrations below 0.06 μg/g were smaller (21.4 ± 8.7 cow-years than those with Se levels above 0.11 μg/g (27.5 ± 14.1 cow-years (P pre partum and decreased incidence of mastitis, ovarian cysts and anoestrus/silent oestrus post partum.

  15. Selenium reduces cadmium uptake and mitigates cadmium toxicity in rice

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Li; Zhou, Weihui; Dai, Huaxin; Cao, Fangbin; Zhang, Guoping [Department of Agronomy, College of Agriculture and Biotechnology, Zijingang Campus, Zhejiang University, Hangzhou, 310058 (China); Wu, Feibo, E-mail: wufeibo@zju.edu.cn [Department of Agronomy, College of Agriculture and Biotechnology, Zijingang Campus, Zhejiang University, Hangzhou, 310058 (China)

    2012-10-15

    Highlights: Black-Right-Pointing-Pointer Se alleviated Cd-toxicity, reduced Cd content and O{sub 2}{center_dot}{sup -}, H{sub 2}O{sub 2}, MDA in rice plants. Black-Right-Pointing-Pointer Se counteracted Cd-induced alterations of antioxidant enzymes. Black-Right-Pointing-Pointer Se suppressed Cd-induced increase in SOD, APX, but elevated depressed CAT activity. Black-Right-Pointing-Pointer Se markedly increased H{sup +}-ATPase, Ca{sup 2+}-ATPase activities in roots under Cd exposure. - Abstract: Hydroponic experiments were performed to investigate physiological mechanisms of selenium (Se) mitigation of Cd toxicity in rice. Exogenous Se markedly reduced Cd concentration in leaves, roots, and stems. Addition or pretreatment of 3 {mu}M Se in 50 {mu}M Cd solution significantly addressed Cd-induced growth inhibition, recovered root cell viability, and dramatically depressed O{sub 2}{center_dot}{sup -}, H{sub 2}O{sub 2}, and malondialdehyde (MDA) accumulation. Supplemental Se counteracted 50 {mu}M Cd-induced alterations of certain antioxidant enzymes, and uptake of nutrients, e.g. depressed Cd-induced increase in leaf and root superoxide dismutase (SOD) and leaf peroxidase (POD) activities, but elevated depressed catalase (CAT) activity; decreased Cd-induced high S and Cu concentrations in both leaves and roots. External Se counteracted the pattern of alterations in ATPase activities induced by Cd, e.g. significantly elevated the depressed root H{sup +}- and Ca{sup 2+}-ATPase activities, but decreased the ascent root Na{sup +}K{sup +}-ATP activity. Results indicate that alleviated Cd toxicity by Se application is related to reduced Cd uptake and ROS accumulation, balanced nutrients, and increased H{sup +}- and Ca{sup 2+}-ATPase activities in rice.

  16. 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...

  17. Effect of feeding selenium-fertilized alfalfa hay on performance of weaned beef calves.

    Directory of Open Access Journals (Sweden)

    Jean A Hall

    Full Text Available Selenium (Se is an essential micronutrient in cattle, and Se-deficiency can affect morbidity and mortality. Calves may have greater Se requirements during periods of stress, such as during the transitional period between weaning and movement to a feedlot. Previously, we showed that feeding Se-fertilized forage increases whole-blood (WB Se concentrations in mature beef cows. Our current objective was to test whether feeding Se-fertilized forage increases WB-Se concentrations and performance in weaned beef calves. Recently weaned beef calves (n = 60 were blocked by body weight, randomly assigned to 4 groups, and fed an alfalfa hay based diet for 7 wk, which was harvested from fields fertilized with sodium-selenate at a rate of 0, 22.5, 45.0, or 89.9 g Se/ha. Blood samples were collected weekly and analyzed for WB-Se concentrations. Body weight and health status of calves were monitored during the 7-wk feeding trial. Increasing application rates of Se fertilizer resulted in increased alfalfa hay Se content for that cutting of alfalfa (0.07, 0.95, 1.55, 3.26 mg Se/kg dry matter for Se application rates of 0, 22.5, 45.0, or 89.9 g Se/ha, respectively. Feeding Se-fertilized alfalfa hay during the 7-wk preconditioning period increased WB-Se concentrations (P Linear<0.001 and body weights (P Linear = 0.002 depending upon the Se-application rate. Based upon our results we suggest that soil-Se fertilization is a potential management tool to improve Se-status and performance in weaned calves in areas with low soil-Se concentrations.

  18. 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.

  19. Chemical form of selenium affects its uptake, transport, and glutathione peroxidase activity in the human intestinal Caco-2 cell model.

    Science.gov (United States)

    Zeng, Huawei; Jackson, Matthew I; Cheng, Wen-Hsing; Combs, Gerald F

    2011-11-01

    Determining the effect of selenium (Se) chemical form on uptake, transport, and glutathione peroxidase activity in human intestinal cells is critical to assess Se bioavailability at nutritional doses. In this study, we found that two sources of L-selenomethionine (SeMet) and Se-enriched yeast each increased intracellular Se content more effectively than selenite or methylselenocysteine (SeMSC) in the human intestinal Caco-2 cell model. Interestingly, SeMSC, SeMet, and digested Se-enriched yeast were transported at comparable efficacy from the apical to basolateral sides, each being about 3-fold that of selenite. In addition, these forms of Se, whether before or after traversing from apical side to basolateral side, did not change the potential to support glutathione peroxidase (GPx) activity. Although selenoprotein P has been postulated to be a key Se transport protein, its intracellular expression did not differ when selenite, SeMSC, SeMet, or digested Se-enriched yeast was added to serum-contained media. Taken together, our data show, for the first time, that the chemical form of Se at nutritional doses can affect the absorptive (apical to basolateral side) efficacy and retention of Se by intestinal cells; but that, these effects are not directly correlated to the potential to support GPx activity.

  20. Determination of selenium in roasted beans coffee samples consumed in Algeria by radiochemical neutron activation analysis method

    International Nuclear Information System (INIS)

    Messaoudi, Mohammed; Begaa, Samir; Hamidatou, Lylia; Salhi, M'hamed

    2018-01-01

    The essential trace element selenium is a focus of attention due to its effects on human health, there being consequences of both its deficiency and excess. Due to the ultra-trace content of selenium, the neutron activation analysis method (NAA) is difficult to apply. We therefore made use of the radiochemical neutron activation analysis (RNAA) to determine Se at low level concentrations in several consumed food items in Algeria. A radiochemical procedure based on liquid-liquid separation was established in our laboratory. In this research we focused on the determination of selenium in two species of coffee: Arabica and Robusta. The accuracy of the method was assessed by analyzing the certified reference material NIST-SRM 1573a (tomato leaves). The results obtained show a selenium variation from 0.025 to 0.052 μg/g in coffee beans and an average yield of the separation of about 85%. The results of this study were compared with those obtained with samples from Brazilian, Caribbean, Indian and Kenyan coffee beans.

  1. Selenium in Graves' disease

    Directory of Open Access Journals (Sweden)

    Jadwiga Kryczyk

    2013-05-01

    Full Text Available The aim of this study was to present the current state of knowledge of the role of selenium in Graves’ disease. Recently, in the pathogenesis and course of this autoimmune disease, more attention has been paid to the relationship between oxidative stress and the antioxidant system, where selenium compounds play an important role. The thyroid is the organ with the highest selenium concentration in the human body. Selenium compounds, having antioxidant properties, protect thyrocytes against the destructive effects of reactive oxygen species (ROS, which are generated during the synthesis of thyroid hormones. Therefore, strengthening the body’s defense mechanisms, which protect against the formation and activity of ROS during medical treatment of Graves’ disease patients, may be an effective adjuvant in commonly used methods of therapy.

  2. The response of broccoli (Brassica oleracea convar. italica) varieties on foliar application of selenium: uptake, translocation, and speciation.

    Science.gov (United States)

    Šindelářová, Kristýna; Száková, Jiřina; Tremlová, Jana; Mestek, Oto; Praus, Lukáš; Kaňa, Antonín; Najmanová, Jana; Tlustoš, Pavel

    2015-01-01

    A model small-scale field experiment was set up to investigate selenium (Se) uptake by four different varieties of broccoli plants, as well as the effect of Se foliar application on the uptake of essential elements for plants calcium (Ca), copper (Cu), iron (Fe), potassium (K), magnesium (Mg), manganese (Mn), phosphorus (P), sulfur (S), and zinc (Zn). Foliar application of sodium selenate (Na2SeO4) was carried out at two rates (25 and 50 g Se/ha), and an untreated control variant was included. Analyses of individual parts of broccoli were performed, whereby it was found that Se in the plant accumulates mainly in the flower heads and slightly less in the leaves, stems, and roots, regardless of the Se rate and broccoli variety. In most cases, there was a statistically significant increase of Se content in all parts of the plant, while there was no confirmed systematic influence of the addition of Se on the changing intake of other monitored elements. Selenization of broccoli leads to an effective increase in the Se content at a rate of 25 g/ha, whereas the higher rate did not result in a substantial increase of Se content compared to the lower rate in all varieties. Therefore, the rate of 25 g/ha can be recommended as effective to produce broccoli with an increased Se content suitable for consumption. Moreover, Se application resulted in an adequate increase of the main organic compounds of Se, such as selenocystine (SeCys2), selenomethionine (SeMet), and Se-methylselenocysteine (Se-MeSeCys).

  3. Selenium and Other Trace Element Mobility in Waste Products and Weathered Sediments at Parys Mountain Copper Mine, Anglesey, UK

    Directory of Open Access Journals (Sweden)

    Liam A. Bullock

    2017-11-01

    Full Text Available The Parys Mountain copper mining district (Anglesey, North Wales hosts exposed pyritic bedrock, solid mine waste spoil heaps, and acid drainage (ochre sediment deposits. Both natural and waste deposits show elevated trace element concentrations, including selenium (Se, at abundances of both economic and environmental consideration. Elevated concentrations of semi-metals such as Se in waste smelts highlight the potential for economic reserves in this and similar base metal mining sites. Selenium is sourced from the pyritic bedrock and concentrations are retained in red weathering smelt soils, but lost in bedrock-weathered soils and clays. Selenium correlates with Te, Au, Bi, Cd, Hg, Pb, S, and Sb across bedrock and weathered deposits. Man-made mine waste deposits show enrichment of As, Bi, Cu, Sb, and Te, with Fe oxide-rich smelt materials containing high Pb, up to 1.5 wt %, and Au contents, up to 1.2 ppm. The trace elements As, Co, Cu, and Pb are retained from bedrock to all sediments, including high Cu content in Fe oxide-rich ochre sediments. The high abundance and mobility of trace elements in sediments and waters should be considered as potential pollutants to the area, and also as a source for economic reserves of previously extracted and new strategic commodities.

  4. AgSbSe2 and AgSb(S,Se)2 thin films for photovoltaic applications

    International Nuclear Information System (INIS)

    Garza, J.G.; Shaji, S.; Rodriguez, A.C.; Das Roy, T.K.; Krishnan, B.

    2011-01-01

    Silver antimony selenide (AgSbSe 2 ) thin films were prepared by heating sequentially deposited multilayers of antimony sulphide (Sb 2 S 3 ), silver selenide (Ag 2 Se), selenium (Se) and silver (Ag). Sb 2 S 3 thin film was prepared from a chemical bath containing SbCl 3 and Na 2 S 2 O 3 , Ag 2 Se from a solution containing AgNO 3 and Na 2 SeSO 3 and Se thin films from an acidified solution of Na 2 SeSO 3 , at room temperature on glass substrates. Ag thin film was deposited by thermal evaporation. The annealing temperature was 350 deg. C in vacuum (10 -3 Torr) for 1 h. X-ray diffraction analysis showed that the thin films formed were polycrystalline AgSbSe 2 or AgSb(S,Se) 2 depending on selenium content in the precursor films. Morphology and elemental analysis of these films were done using scanning electron microscopy and energy dispersive X-ray spectroscopy. Optical band gap was evaluated from the UV-visible absorption spectra of these films. Electrical characterizations were done using Hall effect and photocurrent measurements. A photovoltaic structure: glass/ITO/CdS/AgSbSe 2 /Al was formed, in which CdS was deposited by chemical bath deposition. J-V characteristics of this structure showed V oc = 435 mV and J sc = 0.08 mA/cm 2 under illumination using a tungsten halogen lamp. Preparation of a photovoltaic structure using AgSbSe 2 as an absorber material by a non-toxic selenization process is achieved.

  5. AgSbSe{sub 2} and AgSb(S,Se){sub 2} thin films for photovoltaic applications

    Energy Technology Data Exchange (ETDEWEB)

    Garza, J.G. [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon, San Nicolas de los Garza, Nuevo Leon (Mexico); Shaji, S. [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon, San Nicolas de los Garza, Nuevo Leon (Mexico); Facultad de Ingenieria Mecanica y Electrica, CIIDIT - Universidad Autonoma de Nuevo Leon, Apodaca, Nuevo Leon (Mexico); Rodriguez, A.C.; Das Roy, T.K. [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon, San Nicolas de los Garza, Nuevo Leon (Mexico); Krishnan, B., E-mail: kbindu_k@yahoo.com [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon, San Nicolas de los Garza, Nuevo Leon (Mexico); Facultad de Ingenieria Mecanica y Electrica, CIIDIT - Universidad Autonoma de Nuevo Leon, Apodaca, Nuevo Leon (Mexico)

    2011-10-01

    Silver antimony selenide (AgSbSe{sub 2}) thin films were prepared by heating sequentially deposited multilayers of antimony sulphide (Sb{sub 2}S{sub 3}), silver selenide (Ag{sub 2}Se), selenium (Se) and silver (Ag). Sb{sub 2}S{sub 3} thin film was prepared from a chemical bath containing SbCl{sub 3} and Na{sub 2}S{sub 2}O{sub 3}, Ag{sub 2}Se from a solution containing AgNO{sub 3} and Na{sub 2}SeSO{sub 3} and Se thin films from an acidified solution of Na{sub 2}SeSO{sub 3}, at room temperature on glass substrates. Ag thin film was deposited by thermal evaporation. The annealing temperature was 350 deg. C in vacuum (10{sup -3} Torr) for 1 h. X-ray diffraction analysis showed that the thin films formed were polycrystalline AgSbSe{sub 2} or AgSb(S,Se){sub 2} depending on selenium content in the precursor films. Morphology and elemental analysis of these films were done using scanning electron microscopy and energy dispersive X-ray spectroscopy. Optical band gap was evaluated from the UV-visible absorption spectra of these films. Electrical characterizations were done using Hall effect and photocurrent measurements. A photovoltaic structure: glass/ITO/CdS/AgSbSe{sub 2}/Al was formed, in which CdS was deposited by chemical bath deposition. J-V characteristics of this structure showed V{sub oc} = 435 mV and J{sub sc} = 0.08 mA/cm{sup 2} under illumination using a tungsten halogen lamp. Preparation of a photovoltaic structure using AgSbSe{sub 2} as an absorber material by a non-toxic selenization process is achieved.

  6. The influence of precursor Cu content and two-stage processing conditions on the microstructure of Cu{sub 2}ZnSnSe{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Márquez-Prieto, J., E-mail: jose.prieto@northumbria.ac.uk [Northumbria Photovoltaic Application Centre, Faculty of Engineering and Environment, Northumbria University, Ellison Building, Newcastle upon Tyne NE1 8ST (United Kingdom); Ren, Y. [Ångström Solar Center, Solid State Electronics, Uppsala University, Uppsala 751 21 (Sweden); Miles, R.W.; Pearsall, N.; Forbes, I. [Northumbria Photovoltaic Application Centre, Faculty of Engineering and Environment, Northumbria University, Ellison Building, Newcastle upon Tyne NE1 8ST (United Kingdom)

    2015-05-01

    This paper reports the influence of processing temperature on the microstructure of Cu{sub 2}ZnSnSe{sub 4} (CZTSe) absorber layers for temperatures between 380 and 550 °C produced using a 2-stage process. X-ray diffraction analysis showed the formation of Cu{sub 2}ZnSnSe{sub 4} over this temperatures range. The Williamson-Hall method was used for microstructural analysis of the CZTSe absorbers, and this showed a progressive decrease of the micro-strain of the CZTSe with increasing selenisation temperature. The influence of precursor Cu content on the microstructure of the CZTSe was also studied. An increase of Cu content in the precursor is correlated to an increase in grain size and a decrease in micro-strain. Raman measurements show an asymmetrical broadening towards lower energies of the main 197 cm{sup −1} mode for Cu-poor compositions. This study provides an insight into the dependency of the crystallinity of CZTSe on composition and synthesis temperature. - Highlights: • We fabricate Cu{sub 2}ZnSnSe{sub 4} thin films by sputtering and post-reactive annealing. • The micro-strain of Cu{sub 2}ZnSnSe{sub 4} increases when Cu content decreases. • The micro-strain of Cu{sub 2}ZnSnSe{sub 4} decreases with increasing processing temperature. • The defect concentration of Cu{sub 2}ZnSnSe{sub 4} increases when Cu content decreases.

  7. Selenium-Induced Toxicity Is Counteracted by Sulfur in Broccoli (Brassica oleracea L. var. italica).

    Science.gov (United States)

    Tian, Ming; Hui, Maixia; Thannhauser, Theodore W; Pan, Siyi; Li, Li

    2017-01-01

    Selenium (Se) is an essential micronutrient for humans. Increasing Se content in food crops offers an effective approach to enhance the consumption of Se in human diets. A thoroughly understanding of the effects of Se on plant growth is important for Se biofortification in food crops. Given that Se is an analog of sulfur (S) and can be toxic to plants, its effect on plant growth is expected to be greatly affected by S nutrition. However, this remains to be further understood. Here, we evaluated the influence of Se treatments on broccoli ( Brassica oleracea L. var. italica ) growth when S was withheld from the growth nutrient solution. We found that Se was highly toxic to plants when S nutrition was poor. In contrast to Se treatments with adequate S nutrition that slightly reduced broccoli growth, the same concentration of Se treatments without S supplementation dramatically reduced plant sizes. Higher Se toxicity was observed with selenate than selenite under low S nutrition. We examined the bases underlying the toxicity. We discovered that the high Se toxicity in low S nutrition was specifically associated with an increased ratio of Se in proteins verse total Se level, enhanced generation of reactive oxygen species, elevated lipid peroxidation causing increased cell membrane damage, and reduced antioxidant enzyme activities. Se toxicity could be counteracted with increased supplementation of S, which is likely through decreasing non-specific integration of Se into proteins and altering the redox system. The present study provides information for better understanding of Se toxicity and shows that adequate S nutrition is important to prevent Se toxicity during biofortification of crops by Se fertilization.

  8. Selenium-Induced Toxicity Is Counteracted by Sulfur in Broccoli (Brassica oleracea L. var. italica

    Directory of Open Access Journals (Sweden)

    Ming Tian

    2017-08-01

    Full Text Available Selenium (Se is an essential micronutrient for humans. Increasing Se content in food crops offers an effective approach to enhance the consumption of Se in human diets. A thoroughly understanding of the effects of Se on plant growth is important for Se biofortification in food crops. Given that Se is an analog of sulfur (S and can be toxic to plants, its effect on plant growth is expected to be greatly affected by S nutrition. However, this remains to be further understood. Here, we evaluated the influence of Se treatments on broccoli (Brassica oleracea L. var. italica growth when S was withheld from the growth nutrient solution. We found that Se was highly toxic to plants when S nutrition was poor. In contrast to Se treatments with adequate S nutrition that slightly reduced broccoli growth, the same concentration of Se treatments without S supplementation dramatically reduced plant sizes. Higher Se toxicity was observed with selenate than selenite under low S nutrition. We examined the bases underlying the toxicity. We discovered that the high Se toxicity in low S nutrition was specifically associated with an increased ratio of Se in proteins verse total Se level, enhanced generation of reactive oxygen species, elevated lipid peroxidation causing increased cell membrane damage, and reduced antioxidant enzyme activities. Se toxicity could be counteracted with increased supplementation of S, which is likely through decreasing non-specific integration of Se into proteins and altering the redox system. The present study provides information for better understanding of Se toxicity and shows that adequate S nutrition is important to prevent Se toxicity during biofortification of crops by Se fertilization.

  9. 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.

  10. 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.

  11. Selenium Uptake and Volatilization by Marine Algae

    Science.gov (United States)

    Luxem, Katja E.; Vriens, Bas; Wagner, Bettina; Behra, Renata; Winkel, Lenny H. E.

    2015-04-01

    Selenium (Se) is an essential trace nutrient for humans. An estimated one half to one billion people worldwide suffer from Se deficiency, which is due to low concentrations and bioavailability of Se in soils where crops are grown. It has been hypothesized that more than half of the atmospheric Se deposition to soils is derived from the marine system, where microorganisms methylate and volatilize Se. Based on model results from the late 1980s, the atmospheric flux of these biogenic volatile Se compounds is around 9 Gt/year, with two thirds coming from the marine biosphere. Algae, fungi, and bacteria are known to methylate Se. Although algal Se uptake, metabolism, and methylation influence the speciation and bioavailability of Se in the oceans, these processes have not been quantified under environmentally relevant conditions and are likely to differ among organisms. Therefore, we are investigating the uptake and methylation of the two main inorganic Se species (selenate and selenite) by three globally relevant microalgae: Phaeocystis globosa, the coccolithophorid Emiliania huxleyi, and the diatom Thalassiosira oceanica. Selenium uptake and methylation were quantified in a batch experiment, where parallel gas-tight microcosms in a climate chamber were coupled to a gas-trapping system. For E. huxleyi, selenite uptake was strongly dependent on aqueous phosphate concentrations, which agrees with prior evidence that selenite uptake by phosphate transporters is a significant Se source for marine algae. Selenate uptake was much lower than selenite uptake. The most important volatile Se compounds produced were dimethyl selenide, dimethyl diselenide, and dimethyl selenyl sulfide. Production rates of volatile Se species were larger with increasing intracellular Se concentration and in the decline phase of the alga. Similar experiments are being carried out with P. globosa and T. oceanica. Our results indicate that marine algae are important for the global cycling of Se

  12. 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.

  13. 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.

  14. 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...

  15. 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...

  16. 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

  17. Biological selenium removal from wastewaters

    NARCIS (Netherlands)

    Lenz, M.

    2008-01-01

    In this thesis, microbial conversion of water-soluble, highly toxic forms of selenium (selenate, selenite) to less bioavailable elemental selenium was investigated. By the exploitation of different groups of microorganisms (selenium-respiring, nitrate-reducing and sulfate-reducing bacteria,

  18. Selenium in human mammary carcinogenesis

    DEFF Research Database (Denmark)

    Overvad, Kim; Grøn, P.; Langhoff, Otto

    1991-01-01

    /l and TNM stage II 76 +/- 13 micrograms selenium/l), indicating disease-mediated changes. The evaluation of selenium as a risk indicator in human breast cancer was therefore restricted to TNM stage I patients (n = 36). Multiple logistic regression analyses including variables associated with selenium levels...

  19. 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.

  20. 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

  1. 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...

  2. Selenium speciation in radix puerariae using ultrasonic assisted extraction combined with reversed phase high performance liquid chromatography-inductively coupled plasma-mass spectrometry after magnetic solid-phase extraction with 5-sulfosalicylic acid functionalized magnetic nanoparticles

    Science.gov (United States)

    Cao, Yupin; Yan, Lizhen; Huang, Hongli; Deng, Biyang

    2016-08-01

    A new method for determination of selenium species in radix puerariae was described. The method consists of sample enrichment with 5-sulfosalicylic acid (SSA)-functionalized silica-coated magnetic nanoparticles (SMNPs), high performance liquid chromatography (HPLC) separation, and online detection using inductively coupled plasma mass spectrometry (ICP-MS). The selenium species were extracted using ultrasonic extraction system with a mixture of protease K and lipase. The SSA-SMNPs were used to enrich trace amounts of selenite [Se(IV)], selenate [Se(VI)], selenomethionine (SeMet), and selenocystine (SeCys2) from lower selenium containing samples. Under the optimal conditions, the limits of detection (3σ) for SeCys2, Se(IV), SeMet and Se(VI) were observed as 0.0023, 0.0015, 0.0043, and 0.0016 ng mL- 1, respectively. The RSD values (n = 6) of method for intraday were observed between 0.5% and 0.9%. The RSD values of method for interday were less than 1.3%. The linear concentration ranges for SeCys2, Se(IV), SeMet and Se(VI) were 0.008-1000, 0.005-200, 0.015-500 and 0.006-200 ng mL- 1, respectively. The detection limits of this method were improved by 10 times due to the enrichment with the SSA-SMNP extraction. The contents of SeCys2, Se(IV), SeMet, and Se(VI) in radix puerariae were determined as 0.0140, 0.171, 0.0178, and 0.0344 μg g- 1, respectively. The recoveries were in the range of 95.6%-99.4% and the RSDs (n = 6) of recoveries were less than 1.5%.

  3. Application of instrumental neutron activation analysis to assess dietary intake of selenium in Korean adults from meat and eggs

    International Nuclear Information System (INIS)

    Moon, J.H.; Kim, S.H.; Chung, Y.S.; Okhee Lee

    2015-01-01

    Thirty three frequently eaten items among meat and eggs were collected and pretreated. Selenium (Se) contents in the diet samples were analyzed using an instrumental neutron activation analysis (INAA). 100 g of beef contains 12.4-50.9 μg of Se; pork, 11.2-22.6 μg; chicken, 10.2-13.7 μg and eggs, 28.6-43.0 μg. Beef innards and chicken eggs contain the highest amounts of Se. This study reveals that Se intake of Korean adults are 28.7 μg/day in men and 27.6 μg/day in women from meat and eggs, which are over 1/2 of the Korean recommended Se intake. (author)

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

    Science.gov (United States)

    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

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

    Directory of Open Access Journals (Sweden)

    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

  6. 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....

  7. 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.

  8. Simultaneous Determination of Arsenic, Manganese, and Selenium in Biological Materials by Neutron-Activation Analysis

    DEFF Research Database (Denmark)

    Heydorn, Kaj; Damsgaard, Else

    1973-01-01

    A new method was developed for the simultaneous determination of arsenic, manganese, and selenium in biological material by thermal-neutron activation analysis. The use of 81 mSe as indicator for selenium permitted a reduction of activation time to 1 hr for a 1 g sample, and the possibility of loss...

  9. 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

    This review is the third update of the Cochrane review "Selenium for preventing cancer". Selenium is a naturally occurring element with both nutritional and toxicological properties. Higher selenium exposure and selenium supplements have been suggested to protect against several types of cancer. To gather and present evidence needed to address two research questions:1. What is the aetiological relationship between selenium exposure and cancer risk in humans?2. Describe the efficacy of selenium supplementation for cancer prevention in humans. We updated electronic searches of the Cochrane Central Register of Controlled Trials (CENTRAL; 2017, Issue 2), MEDLINE (Ovid, 2013 to January 2017, week 4), and Embase (2013 to 2017, week 6), as well as searches of clinical trial registries. We included randomised controlled trials (RCTs) and longitudinal observational studies that enrolled adult participants. We performed random-effects (RE) meta-analyses when two or more RCTs were available for a specific outcome. We conducted RE meta-analyses when five or more observational studies were available for a specific outcome. We assessed risk of bias in RCTs and in observational studies using Cochrane's risk assessment tool and the Newcastle-Ottawa Scale, respectively. We considered in the primary analysis data pooled from RCTs with low risk of bias. We assessed the certainty of evidence by using the GRADE approach. We included 83 studies in this updated review: two additional RCTs (10 in total) and a few additional trial reports for previously included studies. RCTs involved 27,232 participants allocated to either selenium supplements or placebo. For analyses of RCTs with low risk of bias, the summary risk ratio (RR) for any cancer incidence was 1.01 (95% confidence interval (CI) 0.93 to 1.10; 3 studies, 19,475 participants; high-certainty evidence). The RR for estimated cancer mortality was 1.02 (95% CI 0.80 to 1.30; 1 study, 17,444 participants). For the most frequently

  10. Structural and electrical properties of co-evaporated Cu(In,Ga)Se{sub 2} thin films with varied Cu contents

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Min Young; Kim, Girim; Kim, Jongwan; Park, Jae Hwan; Lim, Donggun, E-mail: dglim@ut.ac.kr

    2013-11-01

    Cu(In,Ga)Se{sub 2} (CIGS) thin films were fabricated with varying Cu contents. Cu/(Ga + In) ratios were varied between 0.4 and 1.02. Solar cells were then fabricated by co-evaporation using the CIGS layers as absorbers. The influences of Cu content on the cells' structural, optical and electrical properties were studied. The CIGS thin films were characterized by X-ray diffractometer, scanning electron microscopy, energy-dispersive spectroscopy, four-point probe measurement and Hall measurement. Grain size in the films increased with increasing Cu content. At a Cu/(Ga + In) ratio of 0.86, the (220/204) peak was stronger than the (112) peak and carrier concentration was 1.49 × 10{sup 16} cm{sup −3}. Optimizing the Cu content resulted in a CIGS solar cell with an efficiency of 16.5%. - Highlights: • Improvement of technique to form Cu(In,Ga)Se{sub 2} (CIGS) film by co-evaporation method • Cu/(In + Ga) ratio to improve the efficiency for CIGS thin film solar cell • Cu content effects have been analyzed. • Optimum condition of CIGS layer as an absorber of thin film solar cells.

  11. 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.)

  12. Biocompatibility selenium nanoparticles with an intrinsic oxidase-like activity

    Science.gov (United States)

    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.

  13. 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.

  14. 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.

  15. 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

  16. 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)

  17. 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.

  18. Calcium oxalate druses affect leaf optical properties in selenium-treated Fagopyrum tataricum.

    Science.gov (United States)

    Golob, Aleksandra; Stibilj, Vekoslava; Nečemer, Marijan; Kump, Peter; Kreft, Ivan; Hočevar, Anja; Gaberščik, Alenka; Germ, Mateja

    2018-03-01

    Plants of the genus Fagopyrum contain high levels of crystalline calcium oxalate (CaOx) deposits, or druses, that can affect the leaf optical properties. As selenium has been shown to modify the uptake and accumulation of metabolically important elements such as calcium, we hypothesised that the numbers of druses can be altered by selenium treatment, and this would affect the leaf optical properties. Tartary buckwheat (Fagopyrum tataricum Gaertn.) was grown outdoors in an experimental field. At the beginning of flowering, plants were foliarly sprayed with sodium selenate solution at 10 mg selenium L -1 or only with water. Plant morphological, biochemical, physiological and optical properties were examined, along with leaf elemental composition and content. Se spraying did not affect leaf biochemical and functional properties. However, it increased leaf thickness and the contents of Se in the leaves, and decreased the density of calcium oxalate druses in the leaves. Except Se content, Se spraying did not affect contents of other elements in leaves, including total calcium per dry mass of leaf tissue. Redundancy analysis showed that of all parameters tested, only the calcium oxalate druses parameters were significant in explaining the variability of the leaf reflectance and transmittance spectra. The density of CaOx druses positively correlated with the reflectance in the blue, green, yellow and UV-B regions of the spectrum, while the area of CaOx druses per mm 2 of leaf transection area positively correlated with the transmittance in the green and yellow regions of the spectrum. Copyright © 2018 Elsevier B.V. All rights reserved.

  19. 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

  20. 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

    Background This review is an update of the first Cochrane publication on selenium for preventing cancer (Dennert 2011). Selenium is a metalloid with both nutritional and toxicological properties. Higher selenium exposure and selenium supplements have been suggested to protect against several types of cancers. Objectives Two research questions were addressed in this review: What is the evidence for: an aetiological relation between selenium exposure and cancer risk in humans? andthe efficacy of selenium supplementation for cancer prevention in humans? Search methods We conducted electronic searches of the Cochrane Central Register of Controlled Trials (CENTRAL, 2013, Issue 1), MEDLINE (Ovid, 1966 to February 2013 week 1), EMBASE (1980 to 2013 week 6), CancerLit (February 2004) and CCMed (February 2011). As MEDLINE now includes the journals indexed in CancerLit, no further searches were conducted in this database after 2004. Selection criteria We included prospective observational studies (cohort studies including sub-cohort controlled studies and nested case-control studies) and randomised controlled trials (RCTs) with healthy adult participants (18 years of age and older). Data collection and analysis For observational studies, we conducted random effects meta-analyses when five or more studies were retrieved for a specific outcome. For RCTs, we performed random effects meta-analyses when two or more studies were available. The risk of bias in observational studies was assessed using forms adapted from the Newcastle-Ottawa Quality Assessment Scale for cohort and case-control studies; the criteria specified in the Cochrane Handbook for Systematic Reviews of Interventions were used to evaluate the risk of bias in RCTs. Main results We included 55 prospective observational studies (including more than 1,100,000 participants) and eight RCTs (with a total of 44,743 participants). For the observational studies, we found lower cancer incidence (summary odds ratio (OR) 0

  1. Selenium treatment differentially affects sulfur metabolism in high and low glucosinolate producing cultivars of broccoli (Brassica oleracea L.).

    Science.gov (United States)

    McKenzie, Marian J; Chen, Ronan K Y; Leung, Susanna; Joshi, Srishti; Rippon, Paula E; Joyce, Nigel I; McManus, Michael T

    2017-12-01

    The effect of selenium (Se) application on the sulfur (S)-rich glucosinolate (GSL)-containing plant, broccoli (Brassica oleracea L. var. italica) was examined with a view to producing germplasm with increased Se and GSL content for human health, and to understanding the influence of Se on the regulation of GSL production. Two cultivars differing in GSL content were compared. Increased Se application resulted in an increase in Se uptake in planta, but no significant change in total S or total GSL content in either cultivar. Also no significant change was observed in the activity of ATP sulfurylase (ATPS, EC 2.7.7.4) or O-acetylserine(thiol) lyase (OASTL, EC 2.5.1.47) with increased Se application. However, in the first investigation of APS kinase (APSK, EC 2.7.1.25) expression in response to Se fertilisation, an increase in transcript abundance of one variant of APS kinase 1 (BoAPSK1A) was observed in both cultivars, and an increase in BoAPSK2 transcript abundance was observed in the low GSL producing cultivar. A mechanism by which increased APSK transcription may provide a means of controlling the content of S-containing compounds, including GSLs, following Se uptake is proposed. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  2. 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)

  3. Controls on selenium distribution and mobilization in an irrigated shallow groundwater system underlain by Mancos Shale, Uncompahgre River Basin, Colorado, USA

    Science.gov (United States)

    Mills, Taylor J.; Mast, M. Alisa; Thomas, Judith C.; Keith, Gabrielle L.

    2016-01-01

    Elevated selenium (Se) concentrations in surface water and groundwater have become a concern in areas of the Western United States due to the deleterious effects of Se on aquatic ecosystems. Elevated Se concentrations are most prevalent in irrigated alluvial valleys underlain by Se-bearing marine shales where Se can be leached from geologic materials into the shallow groundwater and surface water systems. This study presents groundwater chemistry and solid-phase geochemical data from the Uncompahgre River Basin in Western Colorado, an irrigated alluvial landscape underlain by Se-rich Cretaceous marine shale. We analyzed Se species, major and trace elements, and stable nitrogen and oxygen isotopes of nitrate in groundwater and aquifer sediments to examine processes governing selenium release and transport in the shallow groundwater system. Groundwater Se concentrations ranged from below detection limit (groundwater nitrate concentrations that maintain oxidizing conditions in the aquifer despite low dissolved oxygen concentrations. High nitrate concentrations in non-irrigated soils and nitrate isotopes indicate nitrate is largely derived from natural sources in the Mancos Shale and alluvial material. Thus, in contrast to areas that receive substantial NO3 inputs through inorganic fertilizer application, Se mitigation efforts that involve limiting NO3 application might have little impact on groundwater Se concentrations in the study area. Soluble salts are the primary source of Se to the groundwater system in the study area at-present, but they constitute a small percentage of the total Se content of core material. Sequential extraction results indicate insoluble Se is likely composed of reduced Se in recalcitrant organic matter or discrete selenide phases. Oxidation of reduced Se species that constitute the majority of the Se pool in the study area could be a potential source of Se in the future as soluble salts are progressively depleted.

  4. Defect chalcopyrite Cu(In{sub 1-x}Ga{sub x}){sub 3}Se{sub 5} (0content Cu(In,Ga) Se{sub 2}-based solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Contreras, M.A.; Wiesner, H.; Niles, D.; Ramanathan, K.; Matson, R. [National Renewable Energy Lab., Golden, CO (United States)] [and others

    1996-05-01

    Crystallographic, optical, and electrical properties of defect chalcopyrite Cu(In{sub 1{minus}x}Ga{sub x}){sub 3}Se{sub 5} (0Se{sub 2} absorber materials is presented. Considering the chalcopyrite/defect chalcopyrite junction model, the authors postulate that the traditionally poor device performance of uniform high-Ga-content absorbers (x>0.3) is due to a relatively inferior character - both structural and electrical - at the very chalcopyrite/defect chalcopyrite interface. They demonstrate that this situation can be circumvented (for absorbers with x>0.3) by properly engineering such an interface by reducing Ga content in the region near the surface of the absorber.

  5. 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

  6. New scientific challenges - the possibilities of using selenium in poultry nutrition and impact on meat quality

    Science.gov (United States)

    Marković, R.; Glišić, M.; Bošković, M.; Baltić, M. Ž.

    2017-09-01

    Physiological stress is one of many concerns facing modern broiler production. In conditions when birds are exposed to stress, supplementation of selenium, which is a crucial glutathione peroxidase enzymatic cofactor, increases the antioxidant capacity of the animals and decreases the harmful effects of free radicals. Dietary selenium improves production performance and health of animals, and positively affects the immune system, the quality, selenium content and fatty acid composition of meat and eggs. There are several different forms of selenium, the most common dietary supplements being an inorganic form (sodium selenite) and anorganic form (selenomethionine). However, in recent years, new forms of selenium, such as a 2-hydroxy-4-methylselenobutanoic acid (HMSeBA) and nanoselenium, which have more bioavailability, bioefficacy, and low toxicity have been designed. In this short comparative overview discusses the effects of inorganic, organic and nanoforms of selenium on production results, glutathione peroxidase activity, meat quality and level of toxicity in poultry.

  7. Current Knowledge on the Importance of Selenium in Food for Living Organisms: A Review.

    Science.gov (United States)

    Kieliszek, Marek; Błażejak, Stanisław

    2016-05-10

    Selenium is one of the elements classified within the group of micronutrients which are necessary in trace amounts for the proper functioning of organisms. Selenium participates in the protection of cells against excess H₂O₂, in heavy metal detoxification, and regulation of the immune and reproductive systems as well. It also ensures the proper functioning of the thyroid gland. Selenium induces the occurrence of the selenoprotein synthesis process involved in the antioxidant defense mechanism of the organism. Recent years have brought much success in the studies on selenium. Anticarcinogenic properties of selenium against some cancers have been reported. Supplementation is increasingly becoming a solution to this problem. A large number of different supplementation methods are promoting studies in this area. Slight differences in the selenium content can result in excess or deficiency, therefore supplementation has to be done carefully and cautiously.

  8. Comparative study on the bioactivation mechanisms and cytotoxicity of Te-phenyl-L-tellurocysteine, Se-phenyl-L-selenocysteine, and S-phenyl-L-cysteine

    NARCIS (Netherlands)

    Rooseboom, Martijn; Vermeulen, Nico P E; Durgut, Fatma; Commandeur, Jan N M

    2002-01-01

    Tellurium compounds are effective antioxidants and chemoprotectors, even more active than their selenium and sulfur analogues. In addition to these properties, some selenium compounds, such as selenocysteine Se-conjugates, possess significant chemopreventive and antitumor activities, and selenol

  9. 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.

  10. Selenium supplementation of Portuguese wheat cultivars through foliar treatment in actual field conditions

    International Nuclear Information System (INIS)

    Catarina Galinha; Pacheco, A.M.G.; Maria do Carmo Freitas; Jose Coutinho; Benvindo Macas; Ana Sofia Almeida

    2013-01-01

    Selenium (Se) is a trace element essential to the well-being and health quality of humankind. Plant-derived foodstuffs, namely cereals, are the major dietary sources of Se in most countries throughout the world, even if Se contents are strongly dependent upon the corresponding levels in cereal-growing soils. Therefore, wheat is one of the staple crops that appears as an obvious candidate for Se biofortification, considering its gross-tonnage production and nutritional relevance worldwide. The present paper focuses on the ability of bread and durum wheat-Triticum aestivum L. and Triticum durum Desf., respectively-to accumulate Se after supplementation via a foliar-addition procedure. Two of the most representative wheat cultivars in Portugal - Jordao (bread) and Marialva (durum) - have been selected for supplementation trials, following the same agronomic practices and field schedules as the regular (non-supplemented) crops of those varieties (sowing: November 2010; harvesting: July 2011). Foliar additions were performed at the booting and grain-filling stages, using sodium selenate and sodium selenite solutions at three different Se concentrations-equivalent to field supplementation rates of 4, 20 and 100 g of Se per ha-with and without potassium iodide. Selenium contents in wheat grains obtained under foliar application are compared to data from regular wheat samples (field blanks) grown at the same soil/season, yet devoid of any Se supplementation. Total Se in all field samples was determined by cyclic neutron activation analysis (CNAA), via the short-lived nuclide 77m Se (half-life time: 17.5 s), in the Portuguese Research Reactor (RPI; CTN-IST, Sacavem). Quality control of the analytical procedure was asserted through concurrent analyses of NIST-SRM R 1567a (Wheat Flour). Results show that foliar additions can increase Se contents in mature grains up to 15 and 40 times for Marialva and Jordao, respectively, when compared to non-supplemented crops. Jordao and

  11. 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.

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

    Directory of Open Access Journals (Sweden)

    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.

  13. Novel selenium containing boro-phosphate glasses: Preparation and structural study

    International Nuclear Information System (INIS)

    Ciceo-Lucacel, R.; Radu, T.; Ponta, O.; Simon, V.

    2014-01-01

    We synthesized a new boro-phosphate glass system with different %mol SeO 2 content by conventional melt quenching technique. All samples were obtained in a glassy state with the vitreous structure confirmed by X-ray diffraction analysis. Scanning electron microscopy (SEM) revealed some non-homogeneous domains on the glasses surface, and their tendency to link each other once the selenium oxide content increases. Energy-dispersive X-ray analysis (EDAX) indicated similar elemental composition in different regions of each sample. X-ray photoelectron spectroscopy (XPS) was used to determine the nature of chemical bonding and the elemental composition at the sample surfaces, and Fourier transform infrared (FT-IR) spectroscopy was used to determine the structural groups in the obtained glass structure. Based on FT-IR results, the glass structure at short range order consists mainly of small phosphate units such as pyrophosphate (i.e. P 2 O 7 4− dimmers or terminating groups at the end of phosphate chains) and some metaphosphate (i.e. PO 3 − middle groups in the phosphate chains) units. The boron atoms are mainly placed in three-coordinated sites in BØ 3 or BØ 2 O − units. A small contribution of BØ 4 − units was also detected from the FT-IR spectra of glasses. For SeO 2 content higher than 5 mol%, the modifier role of selenium ions is strongly reflected on the local structure dominated in this case by pyrophosphate units. - Highlights: • New P 2 O 5 -CaO-B 2 O 3 -SeO 2 glasses synthesized by conventional melt quenching method. • Evidences for the Se ions modifier role in the local structure by FT-IR and XPS. • Significant advances in understanding the structural properties of the new system

  14. Impact of DDGS-supplemented diet with or without vitamin E and selenium supplementation on the fatty acid profile of beef

    Directory of Open Access Journals (Sweden)

    Holló I.

    2016-12-01

    Full Text Available The impact of supplementation of vitamin E or organic selenium in DDGS (dried distillers grains with solubles diet on fatty acid composition in two meat cuts of finishing Holstein bulls was investigated. Twenty-four Holstein bulls were allotted to treatments in three groups of eight bulls per group for a 100-day trial. The treatments were adequate Se and vitamin E supplementation in control group (C, supranutritional vitamin E supplementation in vitamin Group E (E, supranutritional Se supplementation in selenium group (Se. At similar age, slaughtering Group C had higher slaughter/carcass weight and EUROP fat score than Se counterparts. The killing out percentage and proximate composition of muscles differed among treatments. Inclusion of the vitamin E or Se supplement led to expected increases (P < 0.05 in vitamin E and Se contents of the brisket and loin. Higher vitamin E concentration caused significant lower SFA and greater PUFA. Higher Se level influenced significant SFA in brisket and PUFA in both muscles. Vitamin E or Se dietary treatments in DDGS-supplemented diet resulted in beef meat cuts considerably beneficial PUFA/SFA but markedly higher n-6/n-3 PUFA ratio and even higher health index in both meat samples opposite to Group C.

  15. Effect of selenium nanoparticles with different sizes in primary cultured intestinal epithelial cells of crucian carp, Carassius auratus gibelio

    Directory of Open Access Journals (Sweden)

    Wang YB

    2013-10-01

    Full Text Available Yanbo Wang, Xuxia Yan, Linglin Fu Marine Resources and Nutrition Biology Research Center, Food Quality and Safety Department, Zhejiang Gongshang University, Hangzhou, People's Republic of China Abstract: Nano-selenium (Se, with its high bioavailability and low toxicity, has attracted wide attention for its potential application in the prevention of oxidative damage in animal tissues. However, the effect of nano-Se of different sizes on the intestinal epithelial cells of the crucian carp (Carassius auratus gibelio is poorly understood. Our study showed that different sizes and doses of nano-Se have varied effects on the cellular protein contents and the enzyme activities of secreted lactate dehydrogenase, intracellular sodium potassium adenosine triphosphatase, glutathione peroxidase, and superoxide dismutase. It was also indicated that nano-Se had a size-dependent effect on the primary intestinal epithelial cells of the crucian carp. Thus, these findings may bring us a step closer to understanding the size effect and the bioavailability of nano-Se on the intestinal tract of the crucian carp. Keywords: selenium nanoparticle, intestinal epithelial cell, crucian carp, primary culture

  16. Distribution of Iodine and Selenium in Selected Food Commodities

    Directory of Open Access Journals (Sweden)

    Strapáč I.

    2016-03-01

    Full Text Available The aim of this study was to investigate the distribution of the contents of iodine and selenium in selected food commodities. Fresh food commodities were mineralized and analysed for their iodine and selenium content by Inductively Coupled Plasma-Mass Spectrometry using the calibration curve as the method for determining the contents of the elements. The average fruit and vegetables concentrations of iodine were very low. The cow’s milk, other dairy products, eggs, poultry, fresh water fish, beef, liver, and mushrooms are frequently regarded as the most important natural source of dietary iodine from common foods. The higher concentrations of selenium were recorded in the kidney, liver, pork, beef, poultry, fresh water fish, hen’s eggs, cow’s milk, other dairy products, wheat flour, fats, coffee, peppers, mushrooms and potatoes.

  17. Distribution and accumulation of selenium in wild plants growing naturally in the Gumuskoy (Kutahya) mining area, Turkey.

    Science.gov (United States)

    Sasmaz, Merve; Akgül, Bunyamin; Sasmaz, Ahmet

    2015-05-01

    This study investigated selenium uptake and transport from the soil to 12 plant species in the mining area of Gumuskoy (Kutahya), Turkey. Plant samples and their associated soils were collected and analyzed for Se content by ICP-MS. Mean Se values in the soils, roots, and shoots of all plants were 0.9, 0.6, and 0.8 mg kg(-1), respectively. The mean enrichment coefficients for roots (ECR) and shoots (ECS) of these plants were 0.78 and 0.97. The mean translocation factors (TLF) were 1.33. These values indicate that all 12 plant species had the ability to transfer Se from the roots to the shoot, but that transfer was more efficient in plants with higher ECR and ECS. Therefore, these plants may be useful in phytoremediation in rehabilitating areas contaminated by Se because their ECR, ECS and TLFs are >1.

  18. Variation of sulfur content in Cu(In,Ga)(S,Se){sub 2} thin film solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Knipper, Martin; Knecht, Robin; Riedel, Ingo; Parisi, Juergen [Energy and Semiconductor Research Laboratory, Department of Physics, University of Oldenburg (Germany)

    2011-07-01

    Chalcopyrite thin film solar cells made of the compound semiconductor Cu(In,Ga)(S,Se){sub 2} (CIGSSe) have a strong potential for achieving high efficiencies at low production costs. Volume production of CIGSSe-modules has already started to exploit their favorable attributes such as low cost processing and reasonable module efficiency. In this study we studied industrially produced CIGSSe modules obtained from rapid thermal processing (RTP) for sulfurization. In detail, we investigated the effect of sulfur offer and RTP temperature (500 C to 580 C) on the photoelectric characteristics of small-area solar cells cut from the modules. Current-voltage profiling under standard test conditions revealed a strong influence of the particular process recipe on the open circuit voltage whereas significant variations of the maximum quantum efficiency can be observed. X-ray diffraction was employed to relate these effects to the crystallographic structure of the actual CIGSSe films. Lock-in thermographic imaging was employed to link apparent film inhomogeneities and disruptions to the specific process recipe.

  19. Selenium Biofortification in Radish Enhances Nutritional Quality via Accumulation of Methyl-Selenocysteine and Promotion of Transcripts and Metabolites Related to Glucosinolates, Phenolics, and Amino Acids

    Science.gov (United States)

    Schiavon, Michela; Berto, Chiara; Malagoli, Mario; Trentin, Annarita; Sambo, Paolo; Dall'Acqua, Stefano; Pilon-Smits, Elizabeth A. H.

    2016-01-01

    Two selenium (Se) fertilization methods were tested for their effects on levels of anticarcinogenic selenocompounds in radish (Raphanus sativus), as well as other nutraceuticals. First, radish was grown on soil and foliar selenate applied 7 days before harvest at 0, 5, 10, and 20 mg Se per plant. Selenium levels were up to 1200 mg Se/kg DW in leaves and 120 mg Se/kg DW in roots. The thiols cysteine and glutathione were present at 2–3-fold higher levels in roots of Se treated plants, and total glucosinolate levels were 35% higher, due to increases in glucoraphanin. The only seleno-aminoacid detected in Se treated plants was Se-methyl-SeCys (100 mg/kg FW in leaves, 33 mg/kg FW in roots). The levels of phenolic aminoacids increased with selenate treatment, as did root total nitrogen and protein content, while the level of several polyphenols decreased. Second, radish was grown in hydroponics and supplied with 0, 5, 10, 20, or 40 μM selenate for 1 week. Selenate treatment led to a 20–30% increase in biomass. Selenium concentration was 242 mg Se/kg DW in leaves and 85 mg Se/kg DW in roots. Cysteine levels decreased with Se in leaves but increased in roots; glutatione levels decreased in both. Total glucosinolate levels in leaves decreased with Se treatment due to repression of genes involved in glucosinolates metabolism. Se-methyl-SeCys concentration ranged from 7–15 mg/kg FW. Aminoacid concentration increased with Se treatment in leaves but decreased in roots. Roots of Se treated plants contained elevated transcript levels of sulfate transporters (Sultr) and ATP sulfurylase, a key enzyme of S/Se assimilation. No effects on polyphenols were observed. In conclusion, Se biofortification of radish roots may be achieved via foliar spray or hydroponic supply. One to ten radishes could fulfill the daily human requirement (70 μg) after a single foliar spray of 5 mg selenate per plant or 1 week of 5–10 μM selenate supply in hydroponics. The radishes metabolized

  20. Selenium biofortification in radish enhances nutritional quality via accumulation of methyl-selenocysteine and promotion of transcripts and metabolites related to glucosinolates, phenolics and amino acids

    Directory of Open Access Journals (Sweden)

    Michela Schiavon

    2016-09-01

    Full Text Available Two selenium (Se fertilization methods were tested for their effects on levels of anticarcinogenic selenocompounds in radish (Raphanus sativus, as well as other nutraceuticals. First, radish was grown on soil and foliar selenate applied 7d before harvest at 0, 5, 10 and 20 mg Se per plant. Selenium levels were up to 1,200 mg Se/kg DW in leaves and 120 mg Se/kg DW in roots. The thiols cysteine and glutathione were present at 2-3 fold higher levels in roots of Se treated plants, and total glucosinolate levels were 35% higher, due to increases in glucoraphanin. The only seleno-aminoacid detected in Se treated plants was Se-methyl-SeCys (100 mg/kg FW in leaves, 33 mg/kg FW in roots. The levels of phenolic aminoacids increased with selenate treatment, as did root total nitrogen and protein content, while the level of several polyphenols decreased. Second, radish was grown in hydroponics and supplied with 0, 5, 10, 20, or 40 microM selenate for one week. Selenate treatment led to a 20-30% increase in biomass. Selenium concentration was 242 mg Se/kg DW in leaves and 85 mg Se/kg DW in roots. Cysteine levels decreased with Se in leaves but increased in roots; glutatione levels decreased in both. Total glucosinolate levels in leaves decreased with Se treatment due to repression of genes involved in glucosinolates metabolism. Se-methyl-SeCys concentration ranged from 7-15 mg/kg FW. Aminoacid concentration increased with Se treatment in leaves but decreased in roots. Roots of Se treated plants contained elevated transcript levels of sulfate transporters (Sultr and ATP sulfurylase, a key enzyme of S/Se assimilation. No effects on polyphenols were observed. In conclusion, Se biofortification of radish roots may be achieved via foliar spray or hydroponic supply. One to ten radishes could fulfill the daily human requirement (70 microg after a single foliar spray of 5 mg selenate per plant or one week of 5-10 microM selenate supply in hydroponics. The radishes

  1. Oxidative stress by Se-deficiency and dynamics of biotrace elements

    International Nuclear Information System (INIS)

    Sakuma, Yasunobu; Tsuyuki, Satoshi; Nagayama, Atsuko; Matsuoka, Keisuke; Honda, Chikako; Endo, Kazutoyo

    2006-01-01

    Metal ions such as Mn, Fe, Cu, Zn, Se are located at the center of the antioxidants in biological systems. Selenium (Se) is contained in GSH-Px (glutathione peroxidase), one of the antioxidants, and is related to various other metal ions to keep redox balance in organism. In the present study, Mn contents in cell fractions of liver homogenates of Se-deficient rat, and control (normal) rats were determined by means of INAA. The results showed that the Mn contents in microsomal fraction of male Se-deficient rats were greater than the control for male rats, and that the trend was different for female rats. The results were presented together with the results of SOD and TBARS. (author)

  2. 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

  3. Selenium for the Prevention of Cutaneous Melanoma

    Directory of Open Access Journals (Sweden)

    Douglas Grossman

    2013-03-01

    Full Text Available 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.

  4. 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

  5. Content

    DEFF Research Database (Denmark)

    Keiding, Tina Bering

    secondary levels. In subject matter didactics, the question of content is more developed, but it is still mostly confined to teaching on lower levels. As for higher education didactics, discussions on selection of content are almost non-existent on the programmatic level. Nevertheless, teachers are forced...... curriculum, in higher education, and to generate analytical categories and criteria for selection of content, which can be used for systematic didactical reflection. The larger project also concerns reflection on and clarification of the concept of content, including the relation between content at the level......Aim, content and methods are fundamental categories of both theoretical and practical general didactics. A quick glance in recent pedagogical literature on higher education, however, reveals a strong preoccupation with methods, i.e. how teaching should be organized socially (Biggs & Tang, 2007...

  6. 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.

  7. Selenium and Mercury Interactions in Apex Predators from the Gulf of Trieste (Northern Adriatic Sea

    Directory of Open Access Journals (Sweden)

    Jadran Faganeli

    2018-02-01

    Full Text Available Since the environmental levels of selenium (Se can moderate the bioaccumulation and toxicity of mercury (Hg in marine organisms, their interactions were studied in seawater, sediments, plankton and the benthic (Bull ray Pteromylaeus bovinus, Eagle ray Myliobatis aquila and the pelagic (Pelagic stingray Dasyiatis violacea rays, as apex predators in the Gulf of Trieste (Northern Adriatic Sea. Male and female rays showed no difference in the Se contents in muscle tissue. Pelagic species contained higher Se levels in muscle but slightly lower levels in the livers of both genders. The Hg/Se ratios in seawater dissolved and colloidal fractions, plankton and sediment were <0.5, while those in particulate matter were <1.3. In benthic ray species, a parallel increase in Se and Hg in muscle was observed, so that an increased in Hg (MeHg bioaccumulation results in Se coaccumulation. The Hg/Se ratios (molar in muscle and liver of pelagic and benthic rays were <1.4 and <0.7, respectively. The low levels of Hg in muscle and liver in all the ray species corresponded to low Hg/Se ratios and increases in muscle and liver to 1 at 7 µg/g, dry weight (dw and 5 µg/g dw, respectively, i.e., about 1.6 µg/g wet weight (ww.

  8. How might selenium moderate the toxic effects of mercury in stream fish of the Western USA?

    Science.gov (United States)

    The ability of selenium (Se) to moderate mercury (Hg) toxicity is well established in the literature. Mercury exposures that might otherwise produce toxic effects are counteracted by Se, particularly when Se:Hg molar ratios approach or exceed 1. We analyzed whole body Se and Hg c...

  9. Distribution of soil selenium in China is potentially controlled by deposition and volatilization?

    Science.gov (United States)

    Sun, Guo-Xin; Meharg, Andrew A.; Li, Gang; Chen, Zheng; Yang, Lei; Chen, Song-Can; Zhu, Yong-Guan

    2016-02-01

    Elucidating the environmental drivers of selenium (Se) spatial distribution in soils at a continental scale is essential to better understand it’s biogeochemical cycling to improve Se transfer into diets. Through modelling Se biogeochemistry in China we found that deposition and volatilization are key factors controlling distribution in surface soil, rather than bedrock-derived Se (balance in other terrestrial environments worldwide.

  10. Selecting Lentil Accessions for Global Selenium Biofortification

    Directory of Open Access Journals (Sweden)

    Dil Thavarajah

    2017-08-01

    Full Text Available The biofortification of lentil (Lens culinaris Medikus. has the potential to provide adequate daily selenium (Se to human diets. The objectives of this study were to (1 determine how low-dose Se fertilizer application at germination affects seedling biomass, antioxidant activity, and Se uptake of 26 cultivated lentil genotypes; and (2 quantify the seed Se concentration of 191 lentil wild accessions grown in Terbol, Lebanon. A germination study was conducted with two Se treatments [0 (control and 30 kg of Se/ha] with three replicates. A separate field study was conducted in Lebanon for wild accessions without Se fertilizer. Among cultivated lentil accessions, PI533690 and PI533693 showed >100% biomass increase vs. controls. Se addition significantly increased seedling Se uptake, with the greatest uptake (6.2 µg g−1 by PI320937 and the least uptake (1.1 µg g−1 by W627780. Seed Se concentrations of wild accessions ranged from 0 to 2.5 µg g−1; accessions originating from Syria (0–2.5 µg g−1 and Turkey (0–2.4 µg g−1 had the highest seed Se. Frequency distribution analysis revealed that seed Se for 63% of accessions was between 0.25 and 0.75 µg g−1, and thus a single 50 g serving of lentil has the potential to provide adequate dietary Se (20–60% of daily recommended daily allowance. As such, Se application during plant growth for certain lentil genotypes grown in low Se soils may be a sustainable Se biofortification solution to increase seed Se concentration. Incorporating a diverse panel of lentil wild germplasm into Se biofortification programs will increase genetic diversity for effective genetic mapping for increased lentil seed Se nutrition and plant productivity.

  11. Selecting Lentil Accessions for Global Selenium Biofortification.

    Science.gov (United States)

    Thavarajah, Dil; Abare, Alex; Mapa, Indika; Coyne, Clarice J; Thavarajah, Pushparajah; Kumar, Shiv

    2017-08-26

    The biofortification of lentil ( Lens culinaris Medikus.) has the potential to provide adequate daily selenium (Se) to human diets. The objectives of this study were to (1) determine how low-dose Se fertilizer application at germination affects seedling biomass, antioxidant activity, and Se uptake of 26 cultivated lentil genotypes; and (2) quantify the seed Se concentration of 191 lentil wild accessions grown in Terbol, Lebanon. A germination study was conducted with two Se treatments [0 (control) and 30 kg of Se/ha] with three replicates. A separate field study was conducted in Lebanon for wild accessions without Se fertilizer. Among cultivated lentil accessions, PI533690 and PI533693 showed >100% biomass increase vs. Se addition significantly increased seedling Se uptake, with the greatest uptake (6.2 µg g -1 ) by PI320937 and the least uptake (1.1 µg g -1 ) by W627780. Seed Se concentrations of wild accessions ranged from 0 to 2.5 µg g -1 ; accessions originating from Syria (0-2.5 µg g -1 ) and Turkey (0-2.4 µg g -1 ) had the highest seed Se. Frequency distribution analysis revealed that seed Se for 63% of accessions was between 0.25 and 0.75 µg g -1 , and thus a single 50 g serving of lentil has the potential to provide adequate dietary Se (20-60% of daily recommended daily allowance). As such, Se application during plant growth for certain lentil genotypes grown in low Se soils may be a sustainable Se biofortification solution to increase seed Se concentration. Incorporating a diverse panel of lentil wild germplasm into Se biofortification programs will increase genetic diversity for effective genetic mapping for increased lentil seed Se nutrition and plant productivity.

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

    Directory of Open Access Journals (Sweden)

    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

  13. Determination of selenium status using the nail biologic monitor in a canine model

    International Nuclear Information System (INIS)

    Steven Morris, J.; Spate, V.L.; Ruth Ann Ngwenyama; Waters, D.J.

    2012-01-01

    Toenails and fingernails are routinely used to estimate selenium status in epidemiological studies; however, literature validating nail selenium concentration as a surrogate for critical organs is limited. In this study diets of intact male dogs were selenium supplemented at two physiological levels (3 and 6 μg/kg/day) in two different forms, selenomethionine and selenium-enriched bioformed yeast. The selenium-adequate basal diet consumed by the treatment and control groups during the 4-week run-in period and throughout the trial contained 0.3 ppm selenium. After 7 months the dogs in the two treatment groups and the control group were euthanized. Representative tissue samples from prostate, brain, liver, heart and skeletal muscle were collected, rinsed and frozen. Toenail clippings from multiple toes were also collected. Selenium was determined by neutron activation analysis using Se77m (half life = 17.4 s) at the University of Missouri Research Reactor Center. NIST SRM 1577, Bovine Liver was analyzed as a quality control. The analysts were blinded to control and treatment group assignments. As expected, tissue selenium levels increased proportionally with supplementation. A slightly greater increase in tissue selenium was observed for the purified selenomethionine compared to the bioformed yeast; however this trend was significant only for brain tissue. Toenail selenium concentrations and tissue selenium were highly correlated (p < 0.003) with Pearson coefficients of 0.759 (skeletal muscle), 0.745 (heart), 0.729 (brain), 0.723 (prostate), and 0.632 (liver). The toenail biologic monitor accurately assesses selenium status in skeletal muscle, heart, brain, prostate, and liver in the canine model. (author)

  14. Contrasting food web factor and body size relationships with Hg and Se concentrations in marine biota.

    Directory of Open Access Journals (Sweden)

    Roxanne Karimi

    Full Text Available Marine fish and shellfish are primary sources of human exposure to mercury, a potentially toxic metal, and selenium, an essential element that may protect against mercury bioaccumulation and toxicity. Yet we lack a thorough understanding of Hg and Se patterns in common marine taxa, particularly those that are commercially important, and how food web and body size factors differ in their influence on Hg and Se patterns. We compared Hg and Se content among marine fish and invertebrate taxa collected from Long Island, NY, and examined associations between Hg, Se, body length, trophic level (measured by δ(15N and degree of pelagic feeding (measured by δ(13C. Finfish, particularly shark, had high Hg content whereas bivalves generally had high Se content. Both taxonomic differences and variability were larger for Hg than Se, and Hg content explained most of the variation in Hg:Se molar ratios among taxa. Finally, Hg was more strongly associated with length and trophic level across taxa than Se, consistent with a greater degree of Hg bioaccumulation in the body over time, and biomagnification through the food web, respectively. Overall, our findings indicate distinct taxonomic and ecological Hg and Se patterns in commercially important marine biota, and these patterns have nutritional and toxicological implications for seafood-consuming wildlife and humans.

  15. Contrasting Food Web Factor and Body Size Relationships with Hg and Se Concentrations in Marine Biota

    Science.gov (United States)

    Karimi, Roxanne; Frisk, Michael; Fisher, Nicholas S.

    2013-01-01

    Marine fish and shellfish are primary sources of human exposure to mercury, a potentially toxic metal, and selenium, an essential element that may protect against mercury bioaccumulation and toxicity. Yet we lack a thorough understanding of Hg and Se patterns in common marine taxa, particularly those that are commercially important, and how food web and body size factors differ in their influence on Hg and Se patterns. We compared Hg and Se content among marine fish and invertebrate taxa collected from Long Island, NY, and examined associations between Hg, Se, body length, trophic level (measured by δ15N) and degree of pelagic feeding (measured by δ13C). Finfish, particularly shark, had high Hg content whereas bivalves generally had high Se content. Both taxonomic differences and variability were larger for Hg than Se, and Hg content explained most of the variation in Hg:Se molar ratios among taxa. Finally, Hg was more strongly associated with length and trophic level across taxa than Se, consistent with a greater degree of Hg bioaccumulation in the body over time, and biomagnification through the food web, respectively. Overall, our findings indicate distinct taxonomic and ecological Hg and Se patterns in commercially important marine biota, and these patterns have nutritional and toxicological implications for seafood-consuming wildlife and humans. PMID:24019976

  16. The Thermodynamics of Selenium Minerals in Near-Surface Environments

    Directory of Open Access Journals (Sweden)

    Vladimir Krivovichev

    2017-10-01

    Full Text Available Selenium compounds are relatively rare as minerals; there are presently only 118 known mineral species. This work is intended to codify and systematize the data of mineral systems and the thermodynamics of selenium minerals, which are unstable (selenides or formed in near-surface environments (selenites, where the behavior of selenium is controlled by variations of the redox potential and the acidity of solutions at low temperatures and pressures. These parameters determine the migration of selenium and its precipitation as various solid phases. All selenium minerals are divided into four groups—native selenium, oxide, selenides, and oxysalts—anhydrous selenites (I and hydrous selenites and selenates (II. Within each of the groups, minerals are codified according to the minimum number of independent elements necessary to define the composition of the mineral system. Eh–pH diagrams were calculated and plotted using the Geochemist’s Workbench (GMB 9.0 software package. The Eh–pH diagrams of the Me–Se–H2O systems (where Me = Co, Ni, Fe, Cu, Pb, Zn, Cd, Hg, Ag, Bi, As, Sb, Al and Ca were plotted for the average contents of these elements in acidic waters in the oxidation zones of sulfide deposits. The possibility of the formation of Zn, Cd, Ag and Hg selenites under natural oxidation conditions in near surface environments is discussed.

  17. 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)

  18. Metabolism of manganese, iron, copper, and selenium in calves

    International Nuclear Information System (INIS)

    Ho, S.Y.

    1981-01-01

    Sixteen male Holstein calves were used to study manganese and iron metabolism. The calves were fed one of the following diets for 18 days: control, control + iron, control + manganese, and control + iron and manganese. All calves were dosed orally with manganese-54. Tissue concentrations of manganese, iron and manganese-54 were determined. Small intestinal iron was lower in calves fed the high manganese diet than in controls. Tissue manganese-54 was lower in calves fed a high manganese diet. Fecal manganese content increased in calves fed both high manganese and high manganese-high iron diets. Serum total iron was not affected by the dietary treatments. To study the effects of high dietary levels of copper and selenium on the intracellular distributions of these two elements in liver and kidney cytosol, calves were fed one of four diets for 15 days. These were 0 and 100 ppM supplemental copper and 0 and 1 ppM added selenium. The control diet containing 0.1 ppM of selenium and 15 ppM of copper. All calves were orally dosed 48 hrs prior to sacrifice with selenium-75. A high copper diet increased copper concentrations in all intracellular liver fractions and most kidney fractions. Only the effects in the liver were significant. Less copper was found in the mitochondria fractions in liver and kidney of calves fed a high selenium diet. Three major copper-binding protein peaks were separated from the soluble fractions of calf liver and kidney. Peak 1 appeared to be the major copper-binding protein in liver and kidney cytosol of copper-loaded animals. Added selenium alone or in combination with copper accentuated the copper accumulation in this peak. Most of selenium-75 was recovered in the same peak as the copper. The results of this experiment indicated that the large molecular proteins in liver and kidney cytosol of calves play an important role in copper and selenium-75 metabolism

  19. Genotypic-dependent effects of N fertilizer, glutathione, silicon, zinc, and selenium on proteomic profiles, amino acid contents, and quality of rice genotypes with contrasting grain Cd accumulation.

    Science.gov (United States)

    Cao, Fangbin; Fu, Manman; Wang, Runfeng; Cheng, Wangda; Zhang, Guoping; Wu, Feibo

    2017-07-01

    Soil heavy metal (HM) contamination has posed a serious problem for safe food production. For restricting the translocation of HM into grain, many proteins were regulated to involve in the process. To identify these proteins, 2D-based proteomic analysis was carried out using different rice genotypes with distinct Cd accumulation in grains and as affected by an alleviating regulator (AR) in field experiments. AR application improved grain quality, with increased contents in Glu, Cys, His, Pro, and protein. Twenty-six low-grain HM accumulation-associated protein species were identified and categorized as physiological functions via two-dimensional gel electrophoresis (2DE) and mass spectrometry. Among these proteins, 8, 9, and 9 proteins exhibited higher accumulation, lower accumulation, and unchanged accumulation, respectively, in Xiushui817 (low accumulator) vs R8097 (high accumulator) under control conditions but showed differential accumulation patterns after AR application. These proteins included sucrose synthase 3, alanine aminotransferase, glutelin, cupin family protein, and zinc finger CCCH domain-containing protein 32. The differential expression of these protein species might contribute to decreased HM accumulation in grain via decreasing the protein accumulation which had high affinity to HM or regulating energy metabolism and signal transduction. Our findings provide valuable insights into the mechanisms of low-grain HM accumulation in rice and possible utilization of candidate protein species in developing low-grain HM accumulation genotypes.

  20. 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.

  1. Tracking selenium in the Chalk aquifer of northern France: Sr isotope constraints

    International Nuclear Information System (INIS)

    Cary, L.; Benabderraziq, H.; Elkhattabi, J.; Gourcy, L.; Parmentier, M.; Picot, J.; Khaska, M.; Laurent, A.; Négrel, Ph.

    2014-01-01

    Highlights: • We report the chemistry of the Chalk groundwater affected by Se contamination. • Strontium isotopes were used to identify the groundwater bodies and their mixings. • The spatial and temporal Se variability is mainly linked to the presence of Se-rich clays. • Saturation or desaturation of Se-rich clays control Se mobility. - Abstract: Groundwater at the southern and eastern edges of France’s Paris Basin has a selenium content that at times exceeds the European Framework Directive’s drinking-water limit value of 10 μg/L. To better understand the dynamics of the Chalk groundwater being tapped to supply the city of Lille and the Se origins, we used a combination of geochemical and isotopic tools. Strontium isotopes, coupled with Ca/Sr, Mg/Sr and Se/Sr ratios, were used to identify the main groundwater bodies and their mixings, with the Mg/Sr and Se/Sr ratios constraining a ternary system. Groundwater in the agricultural aquifer-recharge zone represents a first end-member and displays the youngest water ages of the catchment along with the highest Sr isotopic signature (0.70842) and low Se contents. Anaerobic groundwater constitutes a second major end-member affected by water-rock interactions over a long residence time, with the lowest Sr isotopic signature (0.70789) and the lowest Se content, its low SF6 content confirming the contribution of old water. Se-rich groundwater containing up to 30 μg/L of Se represents a third major end-member, with an intermediate Sr isotopic ratio (0.70826), and is mainly constrained by the clayey Se-rich formation overlying the Chalk aquifer. The spatial and temporal Se variability in the groundwater is clearly linked to the presence of this formation identified as Tertiary and also to the hydrological conditions; saturation of the Se-rich clays by oxygenated groundwater enhances Se mobility and also Sr adsorption onto the clays. This multi-tool study including Sr isotopes successfully identified the Se

  2. 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.

  3. Accumulation of selenium in different wheat genotypes and its protective role against various abiotic stress factors

    OpenAIRE

    Özdemir, Özge; Ozdemir, Ozge

    2008-01-01

    Plant-based foods play a critical role in covering daily requirements of human beings for energy and minerals, especially in the developing world. Most of the nutritional compounds existing in cereal grains are the major protective agents against different chronic diseases. One particular compound with high protective effect against different diseases such as cancer and cardiovascular diseases is selenium (Se). It is widely believed that some forms of selenium (Se) are among the most effectiv...

  4. 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)

  5. 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.

  6. Acute selenium poisoning in lambs

    Energy Technology Data Exchange (ETDEWEB)

    Gabbedy, B J; Dickson, J

    1969-10-01

    An outbreak of sodium selenite poisoning is reported in which 180 of 190 six-weeks-old lambs died. The estimated dose rate of the selenium was 6.4 mg/kg body weight. Liver concentrations of selenium at the time of poisoning averaged 64 ppM and 15 days later liver and kidney concentrations of selenium averaged 26 ppM and 7.4 ppM respectively.

  7. Histopathological changes due to the effect of selenium in experimental cockerels

    Directory of Open Access Journals (Sweden)

    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.

  8. Effects of the copper content on the structural and electrical properties of Cu{sub 2}ZnSnSe{sub 4} bulks

    Energy Technology Data Exchange (ETDEWEB)

    Tsega, Moges, E-mail: mogestsega@yahoo.com [Department of Physics, University of the Free State (Qwaqwa Campus), Private Bag X13, Phuthaditjhaba 9866 (South Africa); Department of Physics, Bahir Dar University (Ethiopia); Dejene, F.B.; Koao, L.F. [Department of Physics, University of the Free State (Qwaqwa Campus), Private Bag X13, Phuthaditjhaba 9866 (South Africa)

    2016-01-01

    We have investigated the concept of defect in Cu{sub x}ZnSnSe{sub 4} (x=1.6–2.0) and Cu{sub y}(Zn{sub 0.9}Sn{sub 1.1})Se{sub 4} (y= 1.6–2.0) bulks prepared by liquid-phase sintering at 600 °C for 2 h with soluble sintering aids of Sb{sub 2}S{sub 3} and Te. All samples were found to exhibit p-type semiconductor for Cu{sub x}ZnSnSe{sub 4}, while n-type of behavior obtained at y= 1.8–2.0 for Cu{sub y}(Zn{sub 0.9}Sn{sub 1.1})Se{sub 4} pellets. The Cu vacancy acts as an acceptor point defect to form the p-type semiconductor, and Sn{sup 4+} acts as a donor to form the n-type behavior for the Sn-rich CZTSe. SEM images of pellets show dense surface morphology, and increase in grain size upon Cu inclusion. The largely increased Hall mobility and the slightly changed carrier concentration for Cu{sub y}(Zn{sub 0.9}Sn{sub 1.1})Se{sub 4} with increasing the Cu content is related to the types of its defects. At y=2.0 with carrier concentration of 4.88×10{sup 17} cm{sup −3} showed the highest mobility of around 58 cm{sup 2}/V s. Based upon the proposed point defects, the CZTSe property can be consistently explained.

  9. Selenium in food and health

    National Research Council Canada - National Science Library

    Reilly, Conor

    2006-01-01

    ...) to be a carcinogen and banned as an additive in food. Selenium is considered by some to be a serious hazard to the environment and to animal health. Selenium-contaminated water has brought deformity and death to wildlife in nature reserves in western USA. There is even concern that because of selenium contamination of soil, crops supplied to the great cities of California could become unfit for human consumption. In large areas of China, endemic selenium toxicity is a hazard for locals who depend on cr...

  10. 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

  11. 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.

  12. Decreased reproductive rates in sheep fed a high selenium diet

    Science.gov (United States)

    High Se-containing forages grow on seleniferous soils in many parts of the United States and throughout the world. Selenium is an essential trace element that is required for many physiological processes but can also be either acutely or chronically toxic to livestock. Anecdotal reports of decrease...

  13. Selenium and mercury interactions wtih emphasis on fish tissue

    Science.gov (United States)

    This review addresses the effects of mercury (Hg) in fish as it relates to the health of the fish themselves as well as potential risks of toxicity in wildlife and humans that consume fish. In particular, it addresses selenium (Se) as a bioindicator of susceptibility to harmful e...

  14. Sulfur and selenium isotope separation by distillation

    International Nuclear Information System (INIS)

    Mills, T. R.; McInteer, B. B.; Montoya, J. G.

    1988-01-01

    Sulfur and selenium isotopes are used for labeled compounds and as precursors for radioisotope production; however, both limited availability and high costs are problems. A new method is needed for large-scale separation of these isotopes. Experimental distillation columns were used to measure isotopic separations for sulfur and selenium compounds. The maximum total isotope separation of 32 S vs. 34 S were 1.127 for H 2 S, 1.048 for COS, 0.838 for SF 4 , and 1.058 for CH 3 SH. Relative volatilities of 32 S vs. 34 S are 1.0006 for COS and 0.9976 for SF 4 . There is a reverse isotope effect for carbon in COS. No isotopic separation was observed for dimethyl selenide. The lower mass selenium isotopes in H 2 Se are more volatile. Distillation is a promising method for separating sulfur isotopes on a production scale. Existing distillation technology produced separated isotopes with an effect similar to that found for sulfur in SF 4 . 8 refs., 2 tabs

  15. Sulfur and selenium isotope separation by distillation

    International Nuclear Information System (INIS)

    Mills, T.R.; McInteer, B.B.; Montoya, J.G.

    1989-01-01

    Sulfur and selenium isotopes are used for labeled compounds and as precursors for radioisotope production; however, both limited availability and high costs are problems. A new method is needed for large-scale separation of theses isotopes. Experimental distillation columns were used to measure isotopic separations for sulfur and selenium compounds. The maximum total isotope separations of 32 S vs. 34 S were 1.127 for H 2 S, 1.048 for COS, 0.838 for SF 4 , and 1.058 for CH 3 SH. Relative volatilities of 32 S and 34 S are 1.0006 for COS and 0.9976 for SF 4 . There is a reverse isotope effect for carbon in COS. No isotopic separation was observed for dimethyl selenide. The lower mass selenium isotopes in H 2 Se are more volatile. Distillation is a promising method for separating sulfur isotopes on a production scale. Existing distillation technology produces separated isotopes with an effect similar to that found for sulfur in SF 4 . (author). 8 refs.; 2 tabs

  16. 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

  17. 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.

  18. The Formation Mechanism of Cu(In0.7Ga0.3Se2 Nanoparticles and the Densification Trajectory of the Se-Rich Quaternary Target by Hot Pressing

    Directory of Open Access Journals (Sweden)

    Qiang Ma

    2018-03-01

    Full Text Available In this paper, a method to obtain the CuInGaSe2 (CIGS absorber layer with an appropriate selenium content is put forward, in which a Se-rich target is used to deposit a CIGS thin-film and this film is annealed in a Se-free inert atmosphere. The key issue of this method is the preparation of a Se-rich target with a homogeneous composition and a high-density. The formation mechanism of CuInSe2 and CuGaSe2 is investigated and the results point to the intermediate phase Cu2−xSe playing a role of a nucleation core. The sintering densification trajectory of the target with the addition of extra selenium is researched. Additionally, an effective way to avoid the sintering defects is proposed. Finally, a conversion efficiency of 11.2% for the CIGS solar cell is reached by sputtering from the obtained Se-rich target.

  19. Accumulation of selenium in aquatic systems downstream of a uranium mining operation in northern Saskatchewan, Canada

    International Nuclear Information System (INIS)

    Muscatello, J.R.; Belknap, A.M.; Janz, D.M.

    2008-01-01

    The objective of this study was to investigate the accumulation of selenium in lakes downstream of a uranium mine operation in northern Saskatchewan, Canada. Selenium concentrations in sediment and biota were elevated in exposure areas even though water concentrations were low (<5 μg/L). The pattern (from smallest to largest) of selenium accumulation was: periphyton < plankton and filterer invertebrates < detritivore and predator invertebrates < small bodied (forage) fish and predatory fish. Biomagnification of selenium resulted in an approximately 1.5-6 fold increase in the selenium content between plankton, invertebrates and forage fish. However, no biomagnification was observed between forage fish and predatory fish. Selenium content in organisms from exposure areas exceeded the proposed 3-11 μg/g (dry weight) dietary toxicity threshold for fish, suggesting that the selenium released into these aquatic systems has the potential to bioaccumulate and reach levels that could impair fish reproduction. - Selenium bioaccumulation patterns in a north temperate, cold water aquatic ecosystem were similar to those reported from warm water systems

  20. Muonic X-ray intensities in phosphorus- and selenium modifications

    International Nuclear Information System (INIS)

    Kaeser, K.; Robert-Tissot, B.; Schaller, L.A.; Schellenberg, L.; Schneuwly, H.

    1979-01-01

    Muonic X-ray intensity measurements have been performed at SIN on allotropic modifications of phosphorus (white, red and black) and of selenium (red and black). Structure effects have been found in the intensity ratios of the K-series between amorphous and crystalline modifications of the same element. The effect in the higher series (Se) is less pronounced. On the other hand, the two crystalline phosphorus modifications (red and black) show the same intensity behavior. The root-mean-square radii 2 >sup(1/2) of phosphorus and (natural) selenium were found to be 3.187(3) fm and 4.138(1) fm respectively. (Auth.)

  1. Selenium alleviates cadmium toxicity by preventing oxidative stress in sunflower (Helianthus annuus) seedlings.

    Science.gov (United States)

    Saidi, Issam; Chtourou, Yacine; Djebali, Wahbi

    2014-03-01

    The present study investigated the possible mediatory role of selenium (Se) in protecting plants from cadmium (Cd) toxicity. The exposure of sunflower seedlings to 20μM Cd inhibited biomass production, decreased chlorophyll and carotenoid concentrations and strongly increased accumulation of Cd in both roots and shoots. Similarly, Cd enhanced hydrogen peroxides content and lipid peroxidation as indicated by malondialdehyde accumulation. Pre-soaking seeds with Se (5, 10 and 20μM) alleviated the negative effect of Cd on growth and led to a decrease in oxidative injuries caused by Cd. Furthermore, Se enhanced the activities of catalase, ascorbate peroxidase and glutathione reductase, but lowered that of superoxide dismutase and guaiacol peroxidase. As important antioxidants, ascorbate and glutathione contents in sunflower leaves exposed to Cd were significantly decreased by Se treatment. The data suggest that the beneficial effect of Se during an earlier growth period could be related to avoidance of cumulative damage upon exposure to Cd, thus reducing the negative consequences of oxidative stress caused by heavy metal toxicity. Copyright © 2013 Elsevier GmbH. All rights reserved.

  2. 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.

  3. Effects on the accumulation of calcium, magnesium, iron, manganese, copper and zinc of adding the two inorganic forms of selenium to solution cultures of Zea mays.

    Science.gov (United States)

    Longchamp, M; Angeli, N; Castrec-Rouelle, M

    2016-01-01

    The addition of selenate or selenite to common fertilizers for crop production could be an effective way of producing selenium-rich food and feed. However, this would be feasible only if the increase in plant selenium (Se) content did not negatively influence the uptake of other essential elements. We therefore need to understand the interactions between Se and other major and trace elements during uptake by the plant. This study aimed to evaluate the influence of inorganic forms of Se on the accumulation of selected macronutrients (Ca and Mg) and micronutrients (Fe, Zn, Mn and Cu). Those essential elements are involved in the oxidative balance of cells. Zea mays seedlings were grown hydroponically in growth chambers in nutrient solutions to which we added 10, 50 or 1000 μg.L(-1) of selenate and/or selenite. Cation accumulation was significantly affected by the addition of 50 μg.L(-1) or 1000 μg.L(-1) Se, but not by the presence of 10 μg.L(-1) of Se in the nutrient solution. The highest concentration (1000 μg.L(-1)) of Se in the nutrient solution affected the accumulation of essential cations in Zea mays: selenate tended to increase the accumulation of Mg, Zn and Mn, whereas a selenate/selenite mixture tended to decrease the accumulation of Ca, Mg, Zn and Mn. Only Fe accumulation was unaffected by Se whatever its form or concentration. Selenium may also affect the distribution of cations on Zea mays. For example, levels of Mg and Zn translocation to the shoots were lower in the presence of selenite. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  4. Selenium Sequestration in a Cationic Layered Rare Earth Hydroxide: A Combined Batch Experiments and EXAFS Investigation.

    Science.gov (United States)

    Zhu, Lin; Zhang, Linjuan; Li, Jie; Zhang, Duo; Chen, Lanhua; Sheng, Daopeng; Yang, Shitong; Xiao, Chengliang; Wang, Jianqiang; Chai, Zhifang; Albrecht-Schmitt, Thomas E; Wang, Shuao

    2017-08-01

    Selenium is of great concern owing to its acutely toxic characteristic at elevated dosage and the long-term radiotoxicity of 79 Se. The contents of selenium in industrial wastewater, agricultural runoff, and drinking water have to be constrained to a value of 50 μg/L as the maximum concentration limit. We reported here the selenium uptake using a structurally well-defined cationic layered rare earth hydroxide, Y 2 (OH) 5 Cl·1.5H 2 O. The sorption kinetics, isotherms, selectivity, and desorption of selenite and selenate on Y 2 (OH) 5 Cl·1.5H 2 O at pH 7 and 8.5 were systematically investigated using a batch method. The maximum sorption capacities of selenite and selenate are 207 and 124 mg/g, respectively, both representing the new records among those of inorganic sorbents. In the low concentration region, Y 2 (OH) 5 Cl·1.5H 2 O is able to almost completely remove selenium from aqueous solution even in the presence of competitive anions such as NO 3 - , Cl - , CO 3 2- , SO 4 2- , and HPO 4 2- . The resulting concentration of selenium is below 10 μg/L, well meeting the strictest criterion for the drinking water. The selenate on loaded samples could be desorbed by rinsing with concentrated noncomplexing NaCl solutions whereas complexing ligands have to be employed to elute selenite for the material regeneration. After desorption, Y 2 (OH) 5 Cl·1.5H 2 O could be reused to remove selenate and selenite. In addition, the sorption mechanism was unraveled by the combination of EDS, FT-IR, Raman, PXRD, and EXAFS techniques. Specifically, the selenate ions were exchanged with chloride ions in the interlayer space, forming outer-sphere complexes. In comparison, besides anion exchange mechanism, the selenite ions were directly bound to the Y 3+ center in the positively charged layer of [Y 2 (OH) 5 (H 2 O)] + through strong bidentate binuclear inner-sphere complexation, consistent with the observation of the higher uptake of selenite over selenate. The results presented in

  5. 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

  6. Delineating hierarchy of selenotranscriptome expression and their response to selenium status in chicken central nervous system.

    Science.gov (United States)

    Jiang, Xiu-Qing; Cao, Chang-Yu; Li, Zhao-Yang; Li, Wei; Zhang, Cong; Lin, Jia; Li, Xue-Nan; Li, Jing-Long

    2017-04-01

    Selenium (Se) incorporated in selenoproteins as selenocysteine and supports various important cellular and organismal functions. We recently reported that chicken brain exhibited high priority for Se supply and retention under conditions of dietary Se deficiency and supernutrition Li et al. (2012) . However, the selenotranscriptome expressions and their response to Se status in chicken central nervous system (CNS) are unclear. To better understand the relationship of Se homeostasis and selenoproteins expression in chicken CNS, 1day-old HyLine White chickens were fed a low Se diet (Se-L, 0.028mg/g) supplemented with 4 levels of dietary Se (0 to 5.0mgSe/kg) as Na 2 SeO 3 for 8weeks. Then chickens were dissected for getting the CNS, which included cerebral cortex, cerebellum, thalamus, bulbus cinereus and marrow. The expressions of selenoproteome which have 24 selenoproteins were detected by the quantitative real-time PCR array. The concept of a selenoprotein hierarchy was developed and the hierarchy of different regions in chicken CNS was existence, especially cerebral cortex and bulbus cinereus. The expression of selenoproteins has a hierarch while changing Se content, and Selenoprotein T (Selt), Selenoprotein K (Selk), Selenoprotein W (Selw), Selenoprotein U (Selu), Glutathione peroxidase 3 (Gpx3), Glutathione peroxidase 4 (Gpx4), Selenoprotein P (Sepp1), Selenoprotein O (Selo), Selenoprotein 15 (Sel15), Selenoprotein N (Seln), Glutathione peroxidase 2 (Gpx2) and Selenoprotein P 2 (Sepp2) take more necessary function in the chicken CNS. Therefore, we hypothesize that hierarchy of regulated the transcriptions of selenoproteome makes an important role of CNS Se metabolism and transport in birds. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Understanding reduced inorganic mercury accumulation in rice following selenium application: Selenium application routes, speciation and doses.

    Science.gov (United States)

    Tang, Wenli; Dang, Fei; Evans, Douglas; Zhong, Huan; Xiao, Lin

    2017-02-01

    Selenium (Se) has recently been demonstrated to reduce inorganic mercury (IHg) accumulation in rice plants, while its mechanism is far from clear. Here, we aimed at exploring the potential effects of Se application routes (soil or foliar application with Se), speciation (selenite and selenate), and doses on IHg-Se antagonistic interactions in soil-rice systems. Results of our pot experiments indicated that soil application but not foliar application could evidently reduce tissue IHg concentrations (root: 0-48%, straw: 15-58%, and brown rice: 26-74%), although both application routes resulted in comparable Se accumulation in aboveground tissues. Meanwhile, IHg distribution in root generally increased with amended Se doses in soil, suggesting antagonistic interactions between IHg and Se in root. These results provided initial evidence that IHg-Se interactions in the rhizosphere (i.e., soil or rice root), instead of those in the aboveground tissues, could probably be more responsible for the reduced IHg bioaccumulation following Se application. Furthermore, Se dose rather than Se speciation was found to be more important in controlling IHg accumulation in rice. Our findings regarding the importance of IHg-Se interactions in the rhizosphere, together with the systematic investigation of key factors affecting IHg-Se antagonism and IHg bioaccumulation, advance our understanding of Hg dynamics in soil-rice systems. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. 3D-printed, TiO2 NP-incorporated minicolumn coupled with ICP-MS for speciation of inorganic arsenic and selenium in high-salt-content samples.

    Science.gov (United States)

    Su, Cheng-Kuan; Chen, Wei-Cheng

    2018-04-25

    To extend the applicability of solid phase extraction devices manufactured using 3D printing technologies, a stereolithographic 3D printer and resins incorporating titanium dioxide nanoparticles (TiO 2 NPs) were employed to fabricate a demountable minicolumn with TiO 2 NP-incorporated packing as a sample pretreatment device for the selective extraction of inorganic As and Se species from high-salt-content samples, and to facilitate their analyses when coupled to an inductively coupled plasma mass spectrometer. After optimization, the automatic system enabled highly sensitive determinations of As and Se species with detection limits as low as 0.004-0.033 μg L -1 for As and 0.061-0.128 μg L -1 for Se. Reliability was confirmed through analyses of the reference materials 1643f, SLEW-3, CASS-4, and 2670a, as well as spike analyses of samples of water and human urine. These 3D-printed minicolumns appear to be very useful for multi-elemental speciation of these elements from high-salt-content samples. Thus, the incorporation of active nanomaterials into raw printing resins can enable 3D printing technologies-not only to fabricate functionalized devices for diverse sample pretreatment applications but also to encourage the future development of multifunctional devices for analytical science. Graphical abstract Schematic presentation of a demountable minicolumn fabricated using a stereolithographic 3D printer and the resins incorporating with TiO 2 NPs. They were used to selectively extract As and Se species through controlling the sample acidities.

  9. 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.)

  10. Comparison of Selenium Treatments of Crops in the Field

    DEFF Research Database (Denmark)

    Nielsen, Gunnar Gissel

    1986-01-01

    Field experiments with spring and winter barley and ryegrass were carried out to compare the effect of fertilizers enriched with selenate or selenite with foliar application on the selenium (Se) concentrations in the crops. Application of about 20 g Se/ha given as selenate or about 100 g as selen...... not occur. The choice of method thus depends on the farming practice in the individual cases....

  11. Certification of the contents (mass fraction) of carbon, hydrogen, nitrogen, chlorine, arsenic, cadmium, manganese, mercury, lead, selenium, vanadium and zinc in three coals. Gas coal CRM No. 180; Coking coal CRM No. 181; Steam coal CRM No. 182

    Energy Technology Data Exchange (ETDEWEB)

    Griepink, B; Colinet, E; Wilkinson, H C

    1986-01-01

    The report first describes the preparation of three coal reference materials: Gas coal (BCR No. 180), Coking coal (BCR No. 181) and Steam coal (BCR No. 182). It deals further with the homogeneity and stability tests for major, minor and trace components. The contents (mass fractions) of the elements: C, H, N, Cl, As, Cd, Mn, Hg, Pb, Se, V and Zn are certified. The analytical techniques used in the certification are summarised. All the individual results are given and recommendations for analysis are made.

  12. Selenium implantation in epitaxial gallium arsenide layers

    International Nuclear Information System (INIS)

    Inada, T.; Tokunaga, K.; Taka, S.; Yuge, Y.; Kohzu, H.

    1981-01-01

    Selenium implantation at room temperature in S-doped epitaxial GaAs layers as a means of the formation of n + layers has been investigated. Doping profiles for Se-implanted layers have been examined by a C-V technique and/or a differential Hall effect method. It has been shown that n + layers with a maximum carrier concentration of approx. equal to1.5 x 10 18 cm -3 can be formed by implantation followed by a 15 min annealing at 950 0 C. Contact resistance of ohmic electrodes is reduced by use of the Se-implanted n + layers, resulting in the improvement on GaAs FET performance. Measured minimum noise figure of the Se-implanted GaAs FETs is 0.74 dB at 4 GHz. (orig.)

  13. 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 ...

  14. Determination of total selenium and selenium distribution in the milk phases in commercial cow's milk by HG-AAS

    Energy Technology Data Exchange (ETDEWEB)

    Muniz-Naveiro, Oscar; Dominguez-Gonzalez, Raquel; Bermejo-Barrera, Adela; Bermejo-Barrera, Pilar [University of Santiago de Compostela, Department of Analytical Chemistry, Nutrition and Bromatology, Santiago de Compostela (Spain); Cocho, Jose A. [University Clinical Hospital, Laboratory of Metabolic and Nutritional Disorders, Santiago de Compostela (Spain); Fraga, Jose M. [University Clinical Hospital, Department of Pediatrics, Santiago de Compostela (Spain)

    2005-03-01

    A procedure has been developed for determining the selenium in cow's milk using hydride generation-atomic absorption spectrometry (HG-AAS) following microwave-assisted acid digestion. The selenium distributions in milk whey, fat and micellar casein phases were studied after separating the different phases by ultracentrifugation and determining the selenium in all of them. The detection limits obtained by HG-AAS for the whole milk, milk whey and micellar casein were 0.074, 0.065 and 0.075 {mu}g l{sup -1}, respectively. The accuracy for the whole milk was checked by using a Certified Reference Material CRM 8435 whole milk powder from NIST, and the analytical recoveries for the milk whey and casein micelles were 100.9 and 96.9%, respectively. A mass balance study of the determination of selenium in the different milk phases was carried out, obtaining values of 95.5-100.8%. The total content of selenium was determined in 37 milk samples from 15 different manufacturers, 19 whole milk samples and 18 skimmed milk samples. The selenium levels found were within the 8.5-21 {mu}g l{sup -1} range. The selenium distributions in the different milk phases were studied in 14 whole milk samples, and the highest selenium levels were found in milk whey (47.2-73.6%), while the lowest level was found for the fat phase (4.8-16.2%). A strong correlation was found between the selenium levels in whole milk and the selenium levels in the milk components. (orig.)

  15. Electrochemical preconcentration and hydride generation methods for trace determination of selenium by atomic absorption spectrometry

    International Nuclear Information System (INIS)

    Bye, R.

    1986-01-01

    The use of atomic absorption spectrometry in combination with two different preconcentration/separation techniques for the determination of trace concentrations of selenium is described. Electrochemical preconcentration onto a platinum electrode with a subsequent atomization of selenium is discussed briefly. Several parameters are considered such as the presence of depolarizers, and the temperature of the electrolyzed solutions. Special attention is payed to the efficiency of the atomization step, and a method to improve this is proposed. Applications of the technique to real samples are also reported. Secondly, the separation of the selenium as the volatile selenium hydride from the sample solution is considered. Several papers in this thesis deal with commonly occurring interferants as nickel and copper and with ways of minimizing or avoiding the interferring effects, whereas other papers relate to more theoretical aspects of the hydride generation process. New methods for the determination of selenium in technical samples with high contents of nickel and copper are also presented

  16. 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...

  17. Optimization of Selenium-enriched Candida utilis by Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    ZHANG Fan

    2014-12-01

    Full Text Available The fermentation conditions of selenium enrichment by Candida utilis were studied. Based on the results of the single factor experiment, three factors including the concentration of sodium selenite, inital pH and incubation temperature were selected. The response surface method was used to optimize the various factors. The optimal conditions were obtained as follows: incubation time was 30 h, time of adding selenium was mid-logarithmic, the sodium selenite concentration was 35 mg·L-1 with inital pH of 6.6, incubation concentration of 10%, incubation temperature of 27 ℃, the medium volume of 150 mL/500 mL, respectively. Under the optimal condition, the biomass was 6.87 g·L-1. The total selenium content of Candida utilis was 12 639.7 μg·L-1, and the selenium content of the cells was 1 839.8 μg·g-1, in which sodium selenite conversion rate was 79.1% and the organic selenium was higher than 90%. The actual value of selenium content was substantially consistent with the theoretical value, and the response surface methodology was applicable for the fermentation conditions of selenium enriched by Candida utilis.

  18. Contents

    OpenAIRE

    BAHAR, Mehmet; KİLMEN, Sevilay; Editörleri, Dil; Türkçe, Salih Kürşad DOLUNAY; İngilizce, Selmin SÖYLEMEZ; YAVUZALP, Nuh; ALPAGUT, Uğur; ALTUN, Murat; AYDOĞAN, Yasemin; AVCI, Cemal; DURMUŞ, Soner; KALYONCU, Nesrin; ORBAY, Metin; ÖZBAY, Murat; TAŞPINAR, Mehmet

    2015-01-01

    Yayın Kurulu: Prof.Dr. Uğur ALPAGUT Prof.Dr. Murat ALTUN Prof.Dr. Yasemin AYDOĞAN Prof.Dr. Cemal AVCI Prof.Dr. Soner DURMUŞ Prof.Dr. Nesrin KALYONCU Prof.Dr. Metin ORBAY Prof.Dr. Murat ÖZBAY Prof.Dr. Mehmet TAŞPINAR Doç.Dr. Türkan ARGON Doç.Dr. Zeki ARSAL Doç.Dr. Bayram BIÇAK Doç.Dr. Bahri AYDIN Doç.Dr. Mehmet CANBULAT Doç.Dr. Eyüp COŞKUN Doç.Dr. Nihal DOĞAN Doç.Dr. Tolga ERDOĞAN Doç.Dr. Halit KARATAY Doç.Dr. Kemalettin KUZUCU Doç.Dr. Salih Paşa MEMİŞOĞLU Doç.Dr. Şenay Se...

  19. Pigments content in Сhlorella vulgaris under the influence of the sodium selenite and the ions of metals

    Directory of Open Access Journals (Sweden)

    O. I. Bodnar

    2016-01-01

    Full Text Available We investigated the content of pigments in Chlorella vulgaris Beij. (Chlorophyta under the influence of sodium selenite in concentrations based on Se4+ 0.5, 5.0, 10.0 and 20.0 mg/dm3 during one, three and seven days and under the influence of the simultaneous action of selenite in concentrations 10 mg Se4+/dm3 and ions of Zn2+, Mn2+, Co2+,Cu2+, Fe3+ in concentrations 5.00, 0.25, 0.05, 0.008 and 0.002 mg/dm3over seven days. This research was carried out to establish the conditions for obtaining algal lipidis substance enriched with selenium and biogenic metals in the aquaculture. The content of pigments was determined spectrophotometrically, the cellular walls were separatedby centrifuge in the percoll gradient and investigated microscopically. The pigments content in the Ch. vulgaris increased by 1.5–2.5 times in comparison with the control sample under the influence of 10 mg Se4+/dm3 with and without metal ions, in all variants of experimental influence due to binding of SeО32– with proteins and lipids. We found that selenium was included in all lipid fractions (triacylglycerols, dyacylglycerols, phospholipids, nonetherified fatty acids; the maximum amount of selenium-containing lipids wasrecorded in chloroplasts. The increase in the contents of carotenoids caused by the actions of experimental factors played an exceptional role in the mechanism of antioxidant protection that prevents destruction of chlorophyll and, accordingly, increases its amount in cells. Changes in the functioning of the photosynthetic apparatus of Ch. vulgaris affect the whole complex of metabolic transformation. Thus, the successful cultivation of chlorella, enriched with selenium and biogenic metals, is possible within seven days under the influence of 10 mg Se4+/dm3 and the above-mentioned concentration of metal ions.

  20. 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.

  1. 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.

  2. Elucidating the Impact of Chalcogen Content on the Photovoltaic Properties of Oxychalcogenide Perovkskites: NaMO3-x Qx (M=Nb, Ta; Q=S, Se, Te).

    Science.gov (United States)

    Park, Heesoo; Alharbi, Fahhad H; Sanvito, Stefano; Tabet, Nouar; El-Mellouhi, Fedwa

    2018-03-19

    In the quest for nontoxic and stable perovskites for solar cells, we have conducted a systematic study of the effect of chalcogen content in oxychalcogenide perovskite by using DFT and quasi-particle perturbation theory. We explored the changes in the electronic structure due to the substitution of O atoms in NaNbO 3 and NaTaO 3 perovskite structures with various chalcogens (S, Se, Te) at different concentrations. Interestingly, the introduction of the chalcogen atoms resulted in a drastic reduction in the electronic band gap, which made some of the compounds fall within the visible range of the solar spectrum. In addition, our analysis of the electronic structure shows that the optical transition becomes direct as a result of the strong hybridization between the orbitals of the transition metal and those of the chalcogen ion, in contrast to the indirect band feature of NaNbO 3 and NaTaO 3 . We identified candidates with a high theoretical solar conversion efficiency that approached the Shockley-Queisser limit, which makes them suitable for thin-film solar cell applications. The present work serves as a guideline for experimental efforts by identifying the chalcogen content that should be targeted during the synthetic route of thermodynamically stable and strongly photoactive absorbers for oxychalcogenide perovskites in thin-film solar cells. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. 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)

  4. 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.

  5. Selenium Accumulating Leafy Vegetables Are a Potential Source of Functional Foods

    Directory of Open Access Journals (Sweden)

    Petro E. Mabeyo

    2015-01-01

    Full Text Available Selenium deficiency in humans has been associated with various diseases, the risks of which can be reduced through dietary supplementation. Selenium accumulating plants may provide a beneficial nutrient for avoiding such illnesses. Thus, leafy vegetables such as Amaranthus hybridus, Amaranthus sp., Cucurbita maxima, Ipomoea batatas, Solanum villosum, Solanum scabrum, and Vigna unguiculata were explored for their capabilities to accumulate selenium when grown on selenium enriched soil and for use as a potential source of selenium enriched functional foods. Their selenium contents were determined by spectrophotometry using the complex of 3,3′-diaminobenzidine hydrochloride (DABH as a chromogen. The mean concentrations in the leaves were found to range from 7.90±0.40 to 1.95±0.12 μg/g dry weight (DW, with C. maxima accumulating the most selenium. In stems, the accumulated selenium content ranged from 1.12±0.10 μg/g in Amaranthus sp. to 5.35±0.78 μg/g DW in C. maxima and was hence significantly different (P<0.01. The cancer cell line MDA-MB-231 was used in cytotoxicity assays to determine the anticancer potential of these extracts. With exception of S. scabrum and S. villosum, no cytotoxicity was detected for the selenium enriched vegetable extracts up to 100 μg/mL concentration. Hence, following careful evaluation the studied vegetables may be considered as selenium enriched functional foods.

  6. Levels of trace elements in green turtle eggs collected from Hong Kong: Evidence of risks due to selenium and nickel

    International Nuclear Information System (INIS)

    Lam, James C.W.; Tanabe, Shinsuke; Chan, Simon K.F.; Lam, Michael H.W.; Martin, Michael; Lam, Paul K.S.

    2006-01-01

    Concentrations of 22 trace elements were determined in green turtle (Chelonia mydas) eggs collected from Hong Kong. Concentrations of selenium, lead and nickel in these eggs were generally higher than those reported in other studies. The predicted no effect concentrations (PNEC; ng/g wet weight) of Pb (1000), Se (340 and 6000 for the worst-case and best-case scenarios, respectively) and Ni (17) in the green turtle eggs were estimated. Hazard quotients (HQs) estimate that Se (HQs: 0.2-24.5) and Ni (HQs: 4.0-26.4) may pose some risks to the turtles. Our study also found that concentrations of Ag, Se, Zn, Hg and Pb in the shell of the turtle eggs were significantly correlated with levels in the whole egg contents (yolk + albumen). Once the precise relationships of specific elements are established, egg-shell concentrations may be used as a non-lethal, non-invasive, surrogate for predicting whole egg burden of certain contaminants in marine turtles. - Concentrations of selenium and nickel in green turtle eggs from Hong Kong might pose some risks to the turtles

  7. Levels of trace elements in green turtle eggs collected from Hong Kong: Evidence of risks due to selenium and nickel

    Energy Technology Data Exchange (ETDEWEB)

    Lam, James C.W. [Center for Coastal Pollution and Conservation, Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong (China); Tanabe, Shinsuke [Center for Marine Environmental Studies, Ehime University, Tarumi 3-5-7, Matsuyama 790-8556 (Japan); Chan, Simon K.F. [Agriculture, Fisheries and Conservation Department, Hong Kong SAR Government, Hong Kong, (China); Lam, Michael H.W. [Center for Coastal Pollution and Conservation, Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong (China); Martin, Michael [Center for Coastal Pollution and Conservation, Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong (China); Lam, Paul K.S. [Center for Coastal Pollution and Conservation, Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong (China)]. E-mail: bhpksl@cityu.edu.hk

    2006-12-15

    Concentrations of 22 trace elements were determined in green turtle (Chelonia mydas) eggs collected from Hong Kong. Concentrations of selenium, lead and nickel in these eggs were generally higher than those reported in other studies. The predicted no effect concentrations (PNEC; ng/g wet weight) of Pb (1000), Se (340 and 6000 for the worst-case and best-case scenarios, respectively) and Ni (17) in the green turtle eggs were estimated. Hazard quotients (HQs) estimate that Se (HQs: 0.2-24.5) and Ni (HQs: 4.0-26.4) may pose some risks to the turtles. Our study also found that concentrations of Ag, Se, Zn, Hg and Pb in the shell of the turtle eggs were significantly correlated with levels in the whole egg contents (yolk + albumen). Once the precise relationships of specific elements are established, egg-shell concentrations may be used as a non-lethal, non-invasive, surrogate for predicting whole egg burden of certain contaminants in marine turtles. - Concentrations of selenium and nickel in green turtle eggs from Hong Kong might pose some risks to the turtles.

  8. Novel selenium containing boro-phosphate glasses: preparation and structural study.

    Science.gov (United States)

    Ciceo-Lucacel, R; Radu, T; Ponta, O; Simon, V

    2014-06-01

    We synthesized a new boro-phosphate glass system with different %mol SeO2 content by conventional melt quenching technique. All samples were obtained in a glassy state with the vitreous structure confirmed by X-ray diffraction analysis. Scanning electron microscopy (SEM) revealed some non-homogeneous domains on the glasses surface, and their tendency to link each other once the selenium oxide content increases. Energy-dispersive X-ray analysis (EDAX) indicated similar elemental composition in different regions of each sample. X-ray photoelectron spectroscopy (XPS) was used to determine the nature of chemical bonding and the elemental composition at the sample surfaces, and Fourier transform infrared (FT-IR) spectroscopy was used to determine the structural groups in the obtained glass structure. Based on FT-IR results, the glass structure at short range order consists mainly of small phosphate units such as pyrophosphate (i.e. P2O7(4-) dimmers or terminating groups at the end of phosphate chains) and some metaphosphate (i.e. PO3(-) middle groups in the phosphate chains) units. The boron atoms are mainly placed in three-coordinated sites in BØ3 or BØ2O(-) units. A small contribution of BØ4(-) units was also detected from the FT-IR spectra of glasses. For SeO2 content higher than 5mol%, the modifier role of selenium ions is strongly reflected on the local structure dominated in this case by pyrophosphate units. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Mercury contents in aquatic macrophytes from two reservoirs in the Paraíba do Sul: Guandú river system, SE Brazil

    Directory of Open Access Journals (Sweden)

    M. M. Molisani

    Full Text Available This paper reports on a study to determine the Hg content in the five most abundant aquatic macrophyte species (Elodea densa, Sagittaria montevidensis, Salvinia auriculata, Pistia stratiotes and Eichhornia crassipes in two artificial reservoirs flooded by water diverted from the Paraíba do Sul river, SE Brazil. The potential of these species for Hg accumulation and their role in Hg transport along the river system due to macrophyte management were evaluated. Mercury concentrations were higher in free-floating than in rooted species. Roots were also richer in Hg than were leaves. Dry weight Hg concentrations in leaves and roots from all species varied from 46-246 ng.g-1 to 37-314 ng.g-1, respectively. These values are higher than those reported for uncontaminated lakes in Brazil and in other tropical areas and similar to those reported for moderately contaminated sites. Mercury concentrations can be attributed to fluvial transport from the heavily industrialized Paraíba do Sul river basin. Intensive sampling of Pistia stratiotes from two sites in the Vigário reservoir was performed to evaluate the capacity of Hg incorporation in short periods of time. The results showed a significant negative correlation between Hg content and size class of individual plants, demonstrating the importance of juveniles, fast growing plants in absorbing Hg. The foremost impact related to Hg contents in the studied area concerns the periodic removal of macrophytes for reservoir management, followed by disposal in nearby areas. This results in the mobilization of 0.52 to 1.3 Kg of Hg per year, a significant fraction of the Hg burden present in reservoir waters. Disposal of such material may result in Hg leaching to river systems, affecting the Hg transfer throughout the basin.

  10. Selenium-induced autometallographic demonstration of endogenous zinc in organs of the rainbow trout, Salmo gairdneri

    DEFF Research Database (Denmark)

    Baatrup, E

    1989-01-01

    of selenium obtained by each organ was determined by gamma-spectrometry, and compared with the autometallographic deposition of silver grains. The relative accumulation of selenium in the organs was: liver greater than spleen greater than kidney greater than intestine greater than gills greater than brain......, the intestine, and the gills, whereas, no such grains were found in preparations from fish having received 1 ppm Se. The use of selenium for the histochemical demonstration of endogenous zinc versus exogenous metals is discussed. Also, consideration is given to the question of which part of the total tissue...

  11. Plants and microbes assisted selenium nanoparticles: characterization and application.

    Science.gov (United States)

    Husen, Azamal; Siddiqi, Khwaja Salahuddin

    2014-08-16

    Selenium is an essential trace element and is an essential component of many enzymes without which they become inactive. The Se nanoparticles of varying shape and size may be synthesized from Se salts especially selenite and selenates in presence of reducing agents such as proteins, phenols, alcohols and amines. These biomolecules can be used to reduce Se salts in vitro but the byproducts released in the environment may be hazardous to flora and fauna. In this review, therefore, we analysed in depth, the biogenic synthesis of Se nanoparticles, their characterization and transformation into t- Se, m-Se, Se-nanoballs, Se-nanowires and Se-hollow spheres in an innocuous way preventing the environment from pollution. Their shape, size, FTIR, UV-vis, Raman spectra, SEM, TEM images and XRD pattern have been analysed. The weak forces involved in aggregation and transformation of one nano structure into the other have been carefully resolved.

  12. 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.

  13. Highly efficient CuIn{sub 1-x}Ga{sub x}Se{sub 2-y}S{sub y}/CdS thin-film solar cells by using diethylselenide as selenium precursor

    Energy Technology Data Exchange (ETDEWEB)

    Kadam, Ankur A.; Dhere, Neelkanth G. [Florida Solar Energy Center, University of Central Florida, Cocoa, FL 32922-5703 (United States)

    2010-05-15

    Conventional furnace selenization process was optimized to achieve effective selenization using diethylselenide (C{sub 2}H{sub 5}){sub 2}Se (DESe). An optimized quantity of Na was added to improve V{sub oc}, FF and morphology. Sputter-deposited CuGa and In metallic precursors were homogenized in an inert atmosphere prior to the introduction of DESe followed by rapidly heating to the maximum process temperature to avoid formation of detrimental binary phases. Selenization was carried out in the temperature range 475-515 C followed by sulfurization in dilute H{sub 2}S. Solar cells were completed by depositing CdS heterojunction partner layer, i:ZnO/ZnO:Al window-bilayer and metallic contact fingers. PV conversion efficiency of 13.7% with a V{sub oc} of 540 mV, J{sub sc} of 38.3 mA/cm{sup 2} and FF of 66.3% were obtained on 0.442 cm{sup 2} cell areas. The process can be easily scaled-up for economic large-scale manufacture. (author)

  14. Effect of a dietary supplementation with linseed oil and selenium to growing rabbits on their productive performances, carcass traits and fresh and cooked meat quality.

    Science.gov (United States)

    Matics, Zs; Cullere, M; Szín, M; Gerencsér, Zs; Szabó, A; Fébel, H; Odermatt, M; Radnai, I; Dalle Zotte, A; Szendrő, Zs

    2017-08-01

    The present experiment tested a dietary supplementation with linseed oil and selenium to growing rabbits. The basal diet (B) contained 3% sunflower oil, while it was substituted with 3% linseed oil in the experimental feed (S). The selenium (Se) content of the two diets was 0.10 vs. 0.46 mg/kg. Rabbits were fed with B diet from the age of 18 days. One group was fed with the B diet until 11 weeks of age (group B), whereas the experimental groups were fed with S diet for 1, 2, 3 or 4 weeks (groups S1, S2, S3 and S4, respectively), before slaughtering (11 weeks of age). Live performance and carcass traits of rabbits, fatty acid (FA) profile and selenium content of their hind leg (HL) and Longissimus thoracis et lumborum (LTL) meat were considered in this study. In addition, the effect of two different cooking methods on the nutritional value of the enriched HL meat was also assessed. The tested dietary supplementation only minimally affected the live performance and carcass traits of rabbits. The S supplementation significantly reduced the Σ n-6 FA and increased the Σ n-3 FA of the HL meat and LTL meat, compared to the B diet (p meat and LTL meat of S fed rabbits were significantly enriched in Se reaching a twofold increase in both meat cuts (p meat. The heat treatment affected cooking loss, Se and vitamin E contents as well as the oxidative status of the HL meat (p < 0.001), with the different cooking methods providing different results. In addition, even if the beneficial C20:5 n-3 and C22:6 n-3 decreased with cooking, the n-6/n-3 ratio remained unaffected. Journal of Animal Physiology and Animal Nutrition © 2016 Blackwell Verlag GmbH.

  15. Selenium hyperaccumulation offers protection from cell disruptor herbivores

    Directory of Open Access Journals (Sweden)

    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

  16. Selenium bioaccumulation in fish exposed to coal ash at the Tennessee Valley Authority Kingston spill site.

    Science.gov (United States)

    Mathews, Teresa J; Fortner, Allison M; Jett, R Trent; Morris, Jesse; Gable, Jennifer; Peterson, Mark J; Carriker, Neil

    2014-10-01

    In December 2008, 4.1 million cubic meters of coal ash were released into the Emory and Clinch Rivers by the Tennessee Valley Authority Kingston Fossil Plant. Coal ash contains several contaminants, including the bioaccumulative metalloid selenium (Se). Because Se is predominantly accumulated in aquatic organisms through dietary rather than aqueous exposure, tissue-based toxicity thresholds for Se are currently being considered. The proposed threshold concentrations range between 4 μg/g and 9 μg/g Se (dry wt.) in whole body fish, with a proposed fillet threshold of 11.8 μg/g. In the present study, the authors examined the spatial and temporal trends in Se bioaccumulation and examined the relationship between the Se content in fillets and in whole bodies of fish collected around the Kingston spill site to determine whether Se bioaccumulation was a significant concern at the ash spill site. Whereas Se concentrations in fish (whole bodies and fillets) were elevated at sampling locations affected by the Kingston ash spill relative to reference locations, concentrations do not appear to be above risk thresholds and have not been increasing over the 5-yr period since the spill. These findings are not only relevant to guiding the human health and ecological risk assessments at the Kingston ash spill site, but because of current national discussions on appropriate guidelines for Se in fish as well for the disposal of coal combustion wastes, the results are also relevant to the general understanding of Se bioaccumulation in contaminated water bodies. © 2014 SETAC.

  17. 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

  18. Mercury and selenium relationship in a tropical estuarine fish

    Directory of Open Access Journals (Sweden)

    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.

  19. 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

  20. Effects of Selenite on Unicellular Green Microalga Chlorella pyrenoidosa: Bioaccumulation of Selenium, Enhancement of Photosynthetic Pigments, and Amino Acid Production.

    Science.gov (United States)

    Zhong, Yu; Cheng, Jay J

    2017-12-20

    Microalgae were studied as function bioaccumulators of selenium (Se) for food and feed supplement. To investigate the bioaccumulation of Se and its effects on the unicellular green alga Chlorella pyrenoidosa, the algal growth curve, fluorescence parameters, antioxidant enzyme activity, and fatty acid and amino acid profiles were examined. We found that Se at low concentrations (≤40 mg L -1 ) positively promoted algal growth and inhibited lipid peroxidation and intracellular reactive oxygen species. The antioxidative effect was associated with an increase in the levels of glutathione peroxidase, catalase, linolenic acid, and photosynthetic pigments. Meanwhile, a significant increase in amino acid and organic Se content was also detected in the microalgae. In contrast, we found opposite effects in C. pyrenoidosa exposed to >60 mg L -1 Se. The antioxidation and toxicity appeared to be correlated with the bioaccumulation of excess Se. These results provide a better understanding of the effect of Se on green microalgae, which may help in the development of new technological applications for the production of Se-enriched biomass from microalgae.

  1. Exploratory studies of element substitutions in synthetic tetrahedrite. Part II. Selenium and tellurium as anions in Zn-Fe tetrahedrites

    DEFF Research Database (Denmark)

    Karup-Møller, Sven; Makovicky, E.

    1999-01-01

    -free) compositons do not materialize. The substituted Se tetrahedrite coexists with Cu3SbSe3, (iron-bearing) Cu2-xSe, Cu3SbSe4 plus/minus low Zn-sulfide melt. Selenium does not adopt the role of cation and tellurium that of anion in the tetrahedrite structure. The explanation of the severely restricted composition...

  2. How might selenium moderate the toxic effects of mercury in stream fish of the Western USA? - abstract

    Science.gov (United States)

    The ability of selenium (Se) to moderate mercury (Hg) toxicity is well established in the literature. Mercury exposures that might otherwise produce toxic effects are counteracted by Se, particularly when Se:Hg molar ratios approach or exceed 1. We analyzed whole body Se and Hg c...

  3. Contents

    Directory of Open Access Journals (Sweden)

    Editor IJRED

    2012-11-01

    Full Text Available International Journal of Renewable Energy Development www.ijred.com Volume 1             Number 3            October 2012                ISSN 2252- 4940   CONTENTS OF ARTICLES page Design and Economic Analysis of a Photovoltaic System: A Case Study 65-73 C.O.C. Oko , E.O. Diemuodeke, N.F. Omunakwe, and E. Nnamdi     Development of Formaldehyde Adsorption using Modified Activated Carbon – A Review 75-80 W.D.P Rengga , M. Sudibandriyo and M. Nasikin     Process Optimization for Ethyl Ester Production in Fixed Bed Reactor Using Calcium Oxide Impregnated Palm Shell Activated Carbon (CaO/PSAC 81-86 A. Buasri , B. Ksapabutr, M. Panapoy and N. Chaiyut     Wind Resource Assessment in Abadan Airport in Iran 87-97 Mojtaba Nedaei       The Energy Processing by Power Electronics and its Impact on Power Quality 99-105 J. E. Rocha and B. W. D. C. Sanchez       First Aspect of Conventional Power System Assessment for High Wind Power Plants Penetration 107-113 A. Merzic , M. Music, and M. Rascic   Experimental Study on the Production of Karanja Oil Methyl Ester and Its Effect on Diesel Engine 115-122 N. Shrivastava,  , S.N. Varma and M. Pandey  

  4. The preparation of three selenium-containing Cordyceps militaris polysaccharides: Characterization and anti-tumor activities.

    Science.gov (United States)

    Liu, Fei; Zhu, Zhen-Yuan; Sun, Xiaoli; Gao, Hui; Zhang, Yong-Min

    2017-06-01

    In the present work, three fractions of selenized Cordyceps militaris polysaccharides (SeCPS) named SeCPS- I, SeCPS- II and SeCPS- III were isolated and purified by ultra-filtration. Their selenium content were measured as 541.3, 863.7 and 623.3μg/g respectively by a graphite furnace atomic absorption spectroscopy. The monosaccharide comformation analysis showed that they were mainly consisted of D-Mannose, D-Glucose, and D-Galactose in mole ratios of 1:7.63:0.83, 1:1.34:0.31 and 1:3.77:0.41 respectively. Their structure characteristics were compared by IFR and NMR spectroscopy. Scanning electron microscopy (SEM) and Congo red (CR) spectrophotometric method were used to investigate their morphological characteristics and conformational transition. SeCPS-II showed the strongest anti-tumor effects judging from the result of in vitro anti-tumor assays against two tumor cell lines (hepatocellular carcinoma HepG-2 cells and lung adenocarcinom A549 cells). Copyright © 2017 Elsevier B.V. All rights reserved.

  5. 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

  6. Determination of trace selenium by solid substrate-room temperature phosphorescence enhancing method based on potassium chlorate oxidizing phenyl hydrazine-1,2-dihydroxynaphthalene-3,6-disulfonic acid system

    Science.gov (United States)

    Liu, Jia-Ming; Cui, Xiao-Jie; Li, Lai-Ming; Fu, Geng-Min; Lin, Shao-Xian; Yang, Min-Lan; Xu, Mei-Ying; Wu, Zhi-Qun

    2007-04-01

    A new method for the determination of trace selenium based on solid substrate-room temperature phosphorimetry (SS-RTP) has been established. This method was based on the fact that in HCl-KCl buffer solution, potassium chlorate could oxidize phenyl hydrazine to form chloridize diazo-ion after being heated at 100 °C for 20 min, and then the diazo-ion reacted with 1,2-dihydroxynaphthalene-3,6-disulfonic acid to form red azo-compound which could emit strong room temperature phosphorescence (RTP) signal on filter paper. Selenium could catalyze potassium chlorate oxidizing the reaction between phenyl hydrazine and 1,2-dihydroxynaphthalene-3,6-disulfonic acid, which caused the sharp enhancement of SS-RTP. Under the optimum condition, the relationship between the phosphorescence emission intensity (Δ Ip) and the content of selenium obeyed Beer's law when the concentration of selenium is within the range of 1.60-320 fg spot -1 (or 0.0040-0.80 ng ml -1 with a sample volume of 0.4 μl). The regression equation of working curve can be expressed as Δ Ip = 13.12 + 0.4839 CSe(IV) (fg spot -1) ( n = 6), with correlation coefficient r = 0.9991 and a detection limit of 0.28 fg spot -1 (corresponding to a concentration range of 7.0 × 10 -13 g ml -1 Se(IV), n = 11). After 11-fold measurement, R.S.D. were 2.8 and 3.5% for the samples containing 0.0040 and 0.80 ng ml -1 of Se(IV), respectively. This accurate and sensitive method with good repeatability has been successfully applied to the determination of trace selenium in Chinese wolfberry and egg yolk with satisfactory results. The mechanism of the enhancement of phosphorescence was also discussed.

  7. Acute selenium poisoning in cattle

    Energy Technology Data Exchange (ETDEWEB)

    Shortridge, E H; O' Hara, P J; Marshall, P M

    1971-01-01

    Three hundred and seventy-six (67%) of 557 calves of approximately 150-200 kg live-weight died following subcutaneous injection of a solution containing 100 mg selenium as sodium selenite. Eight per cent of the 254 heifer calves and 56% of the 303 steers died. The calves had endured the stress of being weaned twice and held in stockyards twice as well as encountering wet weather during the 4 days before receiving the selenium. The heifer calves were also vaccinated with Br. abortus strain 19 vaccine at the same time as receiving the selenium. The clinical signs and pathological findings of circulatory failure and myocardial damage were similar to those previously reported in acute selenium poisoning.

  8. 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.

  9. 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.

  10. 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 co