Total Se Content Research Articles

Selenium accumulation, speciation and bioaccessibility in selenium-enriched earthworm (Eisenia fetida)

Selenium (Se) is an essential micronutrient for humans and animals. Earthworm (Eisenia fetida) has been used as animal feed due to its high protein contents and bioactive components. In this laboratory study, earthworm substrates were treated with sodium selenite of 0, 20, or 40 mg kg−1, and further Se accumulation, speciation and bioaccessibility in earthworm tissues were determined. The results showed that in the Se treatments of 20 and 40 mg kg−1 the earthworm biomass and reproduction was not adversely affected, and total Se concentrations in earthworm tissues were 97.78 and 151.56 mg kg−1 dry weight, respectively. Se speciation in E. fetida was extracted with protease XIV, gastric and gastrointestinal enzymes and was analyzed by high performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICP-MS). Se (IV) was largely biotransformed into organoselenium metabolites, including about 45.8% in SeMet, 29.53% in SeCys2 and 7.3% in unidentified organic Se components. A small fraction of <2.23% was remained in inorganic Se (IV) form. Gastrointestinal digestion was the most efficient way to release Se from earthworm tissues, and Se bioaccessibility based on in vitro simulated gastrointestinal digestion testing was up to 90%. This study suggests that Se-enriched E. fetida could become a good source of Se supplementation in animal feed.

Selenate tolerance and selenium hyperaccumulation in the monocot giant reed (Arundo donax), a biomass crop plant with phytoremediation potential

The response of giant reed (Arundo donax L.) to selenium (Se), added as selenate, was studied. The development, stress response, uptake, translocation, and accumulation of Se were documented in three giant reed ecotypes STM (Hungary), BL (USA), and ESP (Spain), representing different climatic zones. Plantlets regenerated from sterile tissue cultures were grown under greenhouse conditions in sand supplemented with 0, 2.5, 5, and 10mgSekg-1 added as sodium selenate. Total Se content was measured in different plant parts using hydride generation atomic fluorescence spectroscopy. All plants developed normally in the 0-5.0mgSekg-1 concentration range regardless of ecotype, but no growth occurred at 10.0mgSekg-1. There were no signs of chlorosis or necrosis, and the photosynthetic machinery was not affected as evidenced by no marked differences in the structure of thylakoid membranes. There was no change in the maximum quantum yield of photosystem II (Fv/Fm ratio) in the three ecotypes under Se stress, except for a significant negative effect in the ESP ecotype in the 5.0mgSekg-1 treatment. Glutathione peroxidase (GPx) activity increased as the Se concentration increased in the growth medium. GPx activity was higher in the shoot system than the root system in all Se treatments. All ecotypes showed great capacity of take up, translocate and accumulate selenium in their stem and leaf. Relative Se accumulation is best described as leaf ˃˃ stem ˃ root. The ESP ecotype accumulated 1783μgg-1 in leaf, followed by BL with 1769μgg-1, and STM with 1606μgg-1 in the 5.0mgSekg-1 treatment. All ecotypes showed high values of translocation and bioaccumulation factors, particularly the ESP ecotype (10.1 and 689, respectively, at the highest tolerated Se supplementation level). Based on these findings, Arundo donax has been identified as the first monocot hyperaccumulator of selenium, because Se concentration in the leaves of all three ecotypes, and also in the stem of the ESP ecotype, is higher than 0.1% (dry weight basis) under the conditions tested. Tolerance up to 5.0mgSekg-1 and the Se hyperaccumulation capacity make giant reed a promising tool for Se phytoremediation.

The Selenium Supplementation Influences Olive Tree Production and Oil Stability Against Oxidation and Can Alleviate the Water Deficiency Effects.

Foliar fertilization with selenium (Se) may well be beneficial in increasing the nutritional and qualitative values of food in Se-deficient regions such as the Mediterranean Basin, and may contribute to an increase in drought resistance in plants. The present study has considered detachment force, flesh firmness, pigmentation, fresh and dry weight, and oil content of olive drupes from Se fertilized olive orchards (Olea europaea L.) under drought stress and well-watered conditions. This study has also evaluated the total Se, Se amino acid, phenol, carotenoid and chlorophyll contents of EVOO, plus its oxidative stability against oxidation. While there was no change in the ripening indexes and the production of olives generally, Se application did increase the total Se, Se methionine, phenol, and carotenoid and chlorophyll contents. The higher concentration of these (bio) chemical compounds in EVOO obtained from Se fertilized plants might well suggest enhanced antioxidant activity. Consequently, EVOO obtained from Se fertilized trees possesses a higher nutritional value and, as indicated by the greater oxidative stability against oxidation, longer shelf life. In addition, under water deficient conditions, a higher fresh olive weight corresponds to a higher level of phenol, carotenoid and chlorophyll, and the chlorophyll-to-carotenoid ratio in Se fertilized trees would appear to confirm the positive role of selenium in alleviating damage caused by drought stress conditions.

Comparative study of high hydrostatic pressure and high temperature short time processing on quality of clear and cloudy Se-enriched kiwifruit juices

Abstract Selenium (Se) distribution was investigated and a comparative study was carried out into the effects of high hydrostatic pressure (HHP) and high temperature short time (HTST) treatments on quality for both clear and cloudy Se-enriched kiwifruit juice (clear-SKJ, cloudy-SKJ). Organic Se which accounted for 62.32% has a wider distribution than inorganic Se in kiwifruits and mainly comprising Se-protein and Se-polysaccharide. The process of separating kiwifruit pomace from juice caused significant decline in Se content with 43.07% and 49.04% in cloudy and clear juices respectively, and the sterilization process of HHP and HTST significantly decreased the Se contents from 50.46 ± 0.42 μg/kg to 39.63 ± 0.51 μg/kg and 37.93 ± 0.08 μg/kg in cloudy-SKJ, respectively. During the storage period, HTST- and HHP-processed juices showed no significant differences in total Se content, and similarly for certain chemical-physical qualities of total soluble solids, titratable acid, viscosity and pH. In addition, HHP (500 MPa/10 min) and HTST (110 °C/8.6 s) treatments inactivated yeasts and molds (Y&M) completely and sustained total aerobic bacteria (TAB) counts below 2.0 Log10 CFU/mL which guaranteed the microbiological safety in clear-SKJ during storage at 4 °C and 25 °C for 42 days, but TAB counts were detected >2.0 Log10 CFU/mL which demonstrated a shorter shelf life in cloudy-SKJ under the same storage conditions. Moreover, the HHP-treated sample showed better quality characteristics compared with the HTST-treated sample during 42-day storage except for total phenols and the storage time at 4 °C was more conducive to the preservation of the juices after HHP and HTST treatments. Industrial relevance Se-enriched kiwifruit juice is a promising Se-enriched beverage product which has high nutrition and economic value. The results obtained underline the different effects of HHP and HTST on quality and storage stability of Se retention, microorganisms, color, total phenols, chlorophyll and other quality-related aspects. This study may provide technical support for the application of HHP or HTST in the Se-enriched kiwifruit juice industry. Furthermore, a non-thermal technique which can improve functional juice properties to meet the demand of consumers for healthier products is provided in this study.

In situ and ex situ bioremediation of seleniferous soils from northwestern India

Selenium (Se) toxicity or deficiency disorders are chiefly associated with Se concentration and speciation in soils. Elevated soil Se content may lead to contamination of water bodies and groundwaters due to the leaching caused by rainfall and irrigation. This study is focused on Se removal by in situ (biostimulation and bioaugmentation) and ex situ (soil washing) bioremediation as well as on its recovery. In this research, in situ bioremediation of Se-rich soil collected from rice fields in Ludhiana, Northwest India was studied in microcosms. The effect of biostimulation was determined by amending soil with different organic sources (fermentable, non-fermentable, and non-hydrolysable electron donors). The effect of bioaugmentation was determined by adding anaerobic granular sludge to the microcosms. With regard to ex situ bioremediation, the Se-rich soil was leached with water and the resulting leachate was biologically treated in an upflow anaerobic sludge blanket (UASB) reactor using lactate as electron donor. The UASB reactor was operated for 78 days in different conditions of lactate (electron donor) dosing to achieve maximum Se removal and recovery as elemental Se(0) on the granular sludge. The effluent of the UASB reactor was regularly analyzed to determine Se removal efficiencies. The effect of biostimulation and bioaugmentation showed no significant difference in terms of Se reduction profiles in the microcosms. This suggested that the indigenous Se-reducing microorganisms and oxidizable organic carbon present in the soil are sufficient for in situ soil bioremediation. During treatment of soil leachate in the UASB reactor, 90% Se removal was achieved irrespective of the lactate dosing and mineral salt medium composition of the reactor influent. Analysis of the granular sludge using scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM-EDS) and powder X-ray diffraction (P-XRD) confirmed the presence of elemental Se on the granular sludge. The total Se concentration in the anaerobic granular sludge amounted to 43.5 (± 0.7) μg Se per gram of granular sludge. In situ bioremediation achieved Se reduction in the Se-rich soil investigated. However, risk of Se re-oxidation and leaching into groundwater after in situ remediation cannot be disregarded. In contrast, during ex situ treatment, effluent from the UASB reactor contained less than the USEPA guideline value 5 μg L−1 Se. This study showed biological treatment of Se-rich soils is suitable for cleaning the soil, Se recovery, and environmentally acceptable effluent discharge of the soil washing leachate treatment.

Spatial variations in soil selenium and residential dietary selenium intake in a selenium-rich county, Shitai, Anhui, China

Shitai, a selenium (Se)-rich county in Anhui, China, has been reported for its resident longevity in the last 20 years. A recent survey by the Anhui Bureau of Geological Survey showed that soil Se contents in the Shitai area ranged from 0.05 to 51.20 mg/kg, with an average of 0.56 mg/kg. To explore the potential relationship between longevity and natural-occurring Se contents in Shitai county, Se concentrations were determined in Shitai’s food chain (including soils and foods) and the daily Se intakes and hair Se contents were calculated for the residents. In the present study, 33 soil samples, 66 food samples and 82 hair samples were randomly collected from field sites, local food markets and male and female residents in downtown Shitai and in four nearby villages (Dashan, Xianyu, Yongfu and Yuantou). The total Se contents in all samples and the levels of water soluble, exchangeable, acid soluble, organic bound and residual Se in soil samples were determined with hydride generation - atomic fluorescence spectrometry. The total Se contents in soils ranged from 227 to 2603 μg/kg, with the averages of 1607 ± 242 μg/kg in Dashan, 1149 ± 118 μg/kg in Xianyu, 521 ± 157 μg/kg in Yongfu, and 363 ± 140 μg/kg in Yuantou. The soil bioavailable Se content (soluble and exchangeable Se) in Dashan was highest (14.98%), followed by Xianyu (13.69%), Yongfu (13.18%) and Yuantou (9.38%). For food samples, the highest Se concentration of grains was 468.5 μg/kg in Dashan, while lowest was observed in downtown (41.7 μg/kg). The estimated daily Se intake of residents in Dashan reached 298.4 μg/d/adult, which is about 5 times higher than the recommend nutrient intake in China (60 μg/d/adult), and 6–10 times higher than the levels observed in Xianyu (47.6 μg/d/adult), Yuantou (46.1 μg/d/adult), Yongfu (40.0 μg/d/adult), and downtown (30.0 μg/d/adult). Although hair Se contents in Dashan (male: 709.2 μg/kg; female: 589.2 μg/kg) were significantly higher than those at the other study sites, no significant relationships between daily Se intakes and hair Se contents were observed. The present study demonstrated that Se levels in soils, foods, resident dietary intake and human hairs in Shitai County varied significantly; therefore, the region could be a unique field site to study the direct relationship between Se and human health.

Effects of selenium application on Se content and speciation in Lentinula edodes

Edible fungi have strong ability to transform inorganic Se into organic forms. Therefore, different concentrations of selenite, selenate and Se-yeast were injected as Se-supplements into substrates to produce Se-enriched Lentinula edodes. The Se content and its speciation distribution in the fruit bodies of L. edodes were analysed at different harvest times. Results indicate that Se concentrations of L. edodes increased first and then decreased over time. Based on Se accumulation in L. edodes, selenium use efficiency was ranked as selenite > selenate > Se-yeast. SeMet was the predominant Se speciation in the fruit bodies of L. edodes. SeMet made up the biggest proportion of total Se content and increased with application time for selenite and selenate treatments, whereas no significant change was found for Se-yeast treatment. This study demonstrates that Se-enriched L. edodes is a good source of dietary Se.

Hydrological and biogeochemical controls governing the speciation and accumulation of selenium in a wetland influenced by mine drainage.

Controls governing the speciation and accumulation of Se in a 3.7-ha marsh influenced by mine drainage were assessed through examination of water balance, water quality, sediment, and plant tissue components. Over the 8-mo study period (April through November, 2009), mean monthly flows ranged from 1600 to 2300 m3 d-1 (hydraulic retention time of 1-3 d). Total Se concentrations in the marsh outflow were lower than the inflow by 0.4 to 6.2 μg L-1 (mean difference = 3.3 μg L-1 ), illustrating Se removal. The Se accumulation pathways are illustrated by elevated concentrations of Se in sediments (3-35 mg kg-1 dry wt) as well as in below-ground (2-41 mg kg-1 dry wt; mean = 10 mg kg-1 dry wt) and above-ground (0.8-6.3 mg kg-1 dry wt; mean = 2 mg kg-1 dry wt) emergent plant tissues. Redox stratification in the shallow water column had a marked effect on Se speciation and behavior, illustrating bottom water removal of dissolved selenate in suboxic horizons and increased mobility of dissolved organo-Se. Mass balance data yielded inflow and outflow loading rates for Se of 27 and 23 g d-1 , respectively (net accumulation rate of 4 g d-1 or 0.11 mg m2 d-1 ). The rate of accumulation as calculated from the mass balance agrees with independently measured rates of Se accumulation in sediments for the site (3.6-8.1 g d-1 or 0.10-0.22 mg m-2 d-1 ). Environ Toxicol Chem 2018;37:1824-1838. © 2018 SETAC.

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

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

Effects of topography and soil properties on soil selenium distribution and bioavailability (phosphate extraction): A case study in Yongjia County, China

Selenium (Se) is an essential trace element for humans. In order to investigate how soil Se is influenced by topography and soil properties, we selected Yongjia County, an area with mountainous topography, as a study area. This study used cultivated soil data to comprehensively analyze the effects of topography and soil properties on Se mobility and bioavailability and to identify the key factors influencing Se distribution in the environment. Factors considered in this study were elevation, slope, topographic wetness index, the coefficient of weathering and eluviation, pH, organic matter, and Fe2O3. The concentration of total soil Se (0.382±0.123mgkg−1) was far higher than the background value of soil in China, and 98% of the soil samples were classified as having moderate Se levels (>0.175mgkg−1), indicating Yongjia County is a Se-rich region in China. Phosphate extracted Se accounted for an average of 9% of the total Se and was significantly associated with soil total Se, Fe2O3, pH, and the coefficient of weathering and eluviation. Fe2O3 primarily controlled Se adsorption, fixation, and availability in soil. Under the geo-environmental conditions in the study area, the total Se in the soil increased first and then decreased with increases in elevation, slope, and the topographic wetness index, and the phosphate extracted Se showed similar patterns except for the elevation. The findings showed that topographical attributes and soil physicochemical properties synthetically influenced the distribution and bioavailability of Se in soil.

Maternal dietary exposure to selenium nanoparticle led to malformation in offspring

Selenium (Se) is an essential element and its biological activity is related to its speciation. It is also well-known that in excess it can cause teratogenesis in fish and birds. In this study we compared dietary toxicity of elemental selenium nanoparticles (SeNPs) with selenite and selenomethionine (Se-Met). Japanese medaka (Oryzias latipes) was used as a laboratory model to determine Se effects on adults and their offspring. Adult females were individually exposed using a dry diet fortified with 0, 10 or 20 µg/g of the three Se species for 7 days and then allowed to breed for 3 days. Fertilization rate and the proportion of malformed offspring were examined. The three Se diets led to significant increase in maternal tissue Se concentration in the order of Se-Met >>selenite > SeNP. However, in terms of proportion of malformed offspring, the effect of Se-Met = selenite > SeNP. The malformations included pericardial edema and craniofacial changes, which were typical for Se toxicity. The mismatch of maternal ovary Se concentration and proportion of malformed offspring suggested total Se concentration is a poor predictor of toxicity and teratogenesis. Comparing expression of four genes related to oxidative stress in maternal tissue also showed that there were significant differences in expression patterns between three Se diets in the order of selenite = SeNP > Se-Met. Our results showed that SeNPs cause similar toxicity as other Se species but require further study to elucidate the underlying mechanism.

Selenium Accumulation, Antioxidant Enzyme Levels, and Amino Acids Composition in Chinese Mitten Crab (Eriocheir sinensis) Fed Selenium-Biofortified Corn.

The effects of selenium (Se)-biofortified corn on the total Se contents, the antioxidant enzyme levels, and the amino acids composition in Chinese mitten crab (Eriocheir sinensis) during the stage of the fifth shelling to maturity were investigated in the present study. The culture density of crabs was 600 per 667 m2, and they were continuously fed 120.4 mg Se from Se-biofortified corn per 667 m2 every two days for 90 days. The results showed that the total muscle Se levels in the crabs were significantly increased (p < 0.05). Activities of hemolymph supernatant enzymes including alkaline phosphatase (AKP), lysozyme (LZM), glutathione peroxidase (GPx), and superoxide dismutase (SOD) were also enhanced (p < 0.05). The protein and crude fat levels at maturity were higher than those at the fourth molt. The levels of total essential amino acids (∑EAAs) and total delicious amino acids (∑DAAs) were significantly increased (p < 0.05). We demonstrate that the feeding of Se-biofortified corn could significantly improve total muscle Se concentrations and hemolymph supernatant antioxidant enzyme activities in Chinese mitten crab, and slow down the rapid decline of ∑EAAs and ∑DAAs at maturity, thus improving the nutritional quality of Chinese mitten crab.

Bioavailability of Hg and Se from seafood after culinary treatments

The present study aims to evaluate the bioavailability of Hg and Se in blacktip shark, Asian tiger shrimp and squid tube samples after three culinary treatments: boiling, frying and sautéing. Cooked and uncooked samples were evaluated for each seafood species with and without addition of spices (salt, lemon juice and garlic). After each culinary treatment, the seafood samples were freeze-dried, ground and stored for further analysis. The following parameters were evaluated and optimized: sample mass, sample size, cooking time and temperature. The determination of total concentration of Hg and Se was carried out by ICP-MS/MS. In order to minimize the memory effects for Hg, an integrated sample introduction system (ISIS) coupled with ICP-MS/MS was used employing water, 5% HNO3 and 5mgL−1 Au for the washing steps. No significant losses of Se in the seafood were observed after culinary treatments with and without spices. For Hg, losses for blacktip shark and Asian tiger shrimp were observed after boiling, frying and sautéing procedures (14 to 33%) with and without spices. Blacktip shark showed the highest Hg concentration, about 245% higher than the maximum level recommended by the official health organizations. The Se/Hg molar ratio was also determined in all samples and blacktip shark showed a Se/Hg molar ratio<1 that can be considered to be a higher risk to health. Mercury presented a significant change in bioavailability due to the influence of all culinary treatments. However, the bioavailability of Se from cooked samples proved to be independent of the culinary treatment.

Biomonitoring of selenoprotein P in human serum by fast affinity chromatography coupled to ICP-MS.

Most of the Se in human serum is bound to selenoprotein P (SEPP1) in which Se is present in form of selenocysteine. The SEPP1 is a new possible biomarker for the Se status and for this reason we developed a fast, simple and reliable method for the quantitative determination of SEPP1 in serum by affinity chromatography coupled to ICP-MS. It is possible to separate SEPP1 from other selenoproteins in serum in only 5 min, which allows high sample throughput in clinical laboratories. Measured and certified concentrations of total Se and Se(SEPP1) are in good agreement for the reference material SRM 1950. The SEPP1 concentration was stable in serum samples of 3 persons for a minimum of 2 weeks. Further results of method validation were described including internal and external quality assurance. The analytical method was applied for a biomonitoring study of the SEPP1 and total Se concentration in human serum of 50 occupationally non-exposed persons living in northern Germany. Concentration ranges and mean concentrations for Se(SEPP1) are 31.1-59.7 and 46.2 μg/L, respectively. The corresponding values for total Se are 62-120 and 83.5 μg/L. The mean percentage of total Se in serum present as SEPP1 is 58%.

Metabolic transformation and urinary excretion of selenium (Se) in rats fed a Se-enriched defatted rapeseed (Brassica napus, L.) diet.

Se-Enriched defatted rapeseed (Se-DRS), a by-product of rapeseed oil production, is high in Se. This study aimed to detect possible changes in Se-metabolism after Se-DRS consumption and to assess its suitability as a Se supplement in monogaster feed. In this experiment, rats were fed three types of diets differing in Se-form: soybean meal, Se-salt and Se-DRS. Potential differences in Se-metabolism were evaluated based on the total Se concentrations along with non-protein Se speciation patterns in the urine and blood serum of the rats. The total Se concentrations were determined using inductively coupled plasma-mass spectrometry (ICP-MS). Se compounds in the samples were identified through high-performance liquid chromatography/ICP-MS. The total Se excretion rate was dose-dependent, and excess of dietary Se was eliminated in the form of Se-sugar 1, regardless of the administered Se-form. The excretion dynamics of dietary selenomethionine (soybean meal) and methylselenocysteine (Se-DRS) were different to that of the mineral Se (Se-salt). The proportions of Se species in the urine were significantly influenced by the Se source. A specific metabolic pathway, resulting in urinary excretion of Se-sugar 2, was observed in animals fed Se-DRS. Neither the total Se concentrations nor the serum Se speciation patterns differed between the animals fed the conventional diet and those fed the Se-DRS-enriched diet. Based on these results, Se-DRS can be considered a suitable Se supplement for monogaster nutrition in Se-deficient regions.

Effects of different concentrations of Se6+ on selenium absorption, transportation, and distribution of citrus seedlings (C. junos cv. Ziyang xiangcheng)

ABSTRACTDifferent concentrations of selenium (Se6+) were added in order to detect the rules of Se absorption, transportation, and distribution in seedlings of Ziyang xiangcheng. After two months of treatments, seedling growth parameters, Se concentrations in different parts, and rhizosphere microbial counts were detected. We found 1–8 mg Se6+/L treatments promoted plant growth, especially at 2 mg/L. The seedling Se concentrations were also improved with the increase of Se dose. Both Se concentrations and total Se content were the largest in leaves, followed by roots and stems. The counts of bacteria and fungi were maximized at the dose of 2 mg Se6+/L. With the increase of Se dose, Se transaction factors were reduced. Moreover, bioconcentration factors (BCFs) viz BCFroot/soil and BCFstem/soil were maximized at the dose of 2 mg/L Se6+. These results indicated that the optimized growth Se content is at the dose of 2 mg Se6+/L.

Macro, trace and toxic elements of 4 different edible wild plants from Karadeniz Region

The study was conducted to assess the content (mg kg -1 fresh wt.) of macro, trace and toxic elements in the 4 different edible wild plants. The percentage of dry matter and ash ranged from 6.77 to 20.56 and 0.79 to 2.26, respectively. The contents of Ca (1074), Fe (160.5), Mn (18.21), Ni (6.11), B (2.61), Cr (0.93), Co (0.50), Mo (1.80), Be (0.009) and Se (0.076) of U. diocia were richer than in other plants. Other hand, K (7742), Mg (954), Al (10.79), V (9.77) and Ag (0.109) in T. orientalis , Zn (12.47), Cu (9.98) and Ba (130.3) in O. umbellatum were taken the highest value. Also As, Hg, Tl, Cd and Pb were determined mg kg -1 level in fresh plants. Conversely, antimony (Sb) in wild plants could not be detected by ICP-MS. The results of statistical analysis of forty plants showed that moisture, total dry matter, ash, K, Ca, Mg, Fe, Zn, Cu, Mn, Ba, Ni, Al, V, B, Cr, Co, Mo, Be, Se, Ag, As, Tl, Cd and Pb contents were varied significantly compared to plant species except for Na and Hg (p<0.05). Consequently, wild plants may be used as popular vegetables in many people diet as a source of minerals (Fe, Cu, Mn, Cr, Mo, K, Zn and Mg). Excessive plant consumption may be adversely affected human health with Cd, As, Hg, Tl and Pb.

Ameliorative Effects of Selenium on Cadmium-Induced Injury in the Chicken Ovary: Mechanisms of Oxidative Stress and Endoplasmic Reticulum Stress in Cadmium-Induced Apoptosis.

Despite the well-established toxicity of cadmium (Cd) to animals and the ameliorative effects of selenium (Se), some specific mechanisms in the chicken ovary are not yet clarified. To explore the mechanism by which the toxicity effect of Cd is induced and explore the effect of supranutritional Se on Cd toxicity in female bird reproduction, forty-eight 50-day-old Isa Brown female chickens were divided randomly into four groups. Group I (control group) was fed the basic diet containing 0.2mg/kg Se. Group II (Se-treated group) was fed the basic diet supplemented with sodium selenite (Na2SeO3), and the total Se content was 2mg/kg. Group III (Se + Cd-treated group) was fed the basic diet supplemented with Na2SeO3; the total Se content was 2mg/kg, and it was supplemented with 150mg/kg cadmium chloride (CdCl2). Group IV (Cd-treated group) was with the basic diet supplemented with 150mg/kg CdCl2. The Cd, estradiol (E2), and progestogen (P4) contents changed after subchronic Cd exposure in chicken ovarian tissue; subsequently, oxidative stress occurred and activated the endoplasmic reticulum (ER) pathway to induce apoptosis. Further, Se decreased the accumulation of Cd in ovarian tissue, increased the E2 and P4 contents, alleviated oxidative stress, and reduced apoptosis via the ER stress pathway. The present results demonstrated that Cd could induce apoptosis via the ER stress pathway in chicken ovarian tissue and that Se had a significant antagonistic effect. These results are potentially valuable for finding a strategy to prevent Cd poisoning.

Hydroxy-selenomethionine: A novel organic selenium source that improves antioxidant status and selenium concentrations in milk and plasma of mid-lactation dairy cows

This study aimed to evaluate the effect of hydroxy-selenomethionine (HMSeBA), a novel organic selenium (Se) source, on milk performance, antioxidative status, and Se concentrations in the milk and plasma of mid-lactation dairy cows compared with that of sodium selenite (SS). Fifty mid-lactation dairy cows with similar days in milk, milk yield, and parity received the same basal diet containing 0.06 mg of Se/kg of DM. They were assigned to 1 of 5 treatments according to a randomized complete block design: negative control (without Se supplementation), SS supplementation (0.3 mg of Se/kg of DM; SS-0.3) or HMSeBA supplementation (0.1, 0.3, or 0.5 mg of Se/kg of DM: SO-0.1, SO-0.3, and SO-0.5, respectively). The experiment lasted for 10 wk, including a pretrial period of 2 wk. The results indicated that neither Se supplementation nor Se source affected dry matter intake, milk yield, milk composition, or blood biochemical parameters, except for milk fat percentage. Simultaneously, milk fat percentage and milk fat yield increased linearly as the quantity of HMSeBA supplementation was increased. Production of 4% FCM and ECM was elevated linearly as dietary HMSeBA increased. The SO-0.3 group showed higher serum activity of glutathione peroxidase, total antioxidant capacity, and superoxide dismutase than the SS-0.3 group, but malondialdehyde content was not affected by Se source. Furthermore, HMSeBA supplementation linearly increased the activities of serum glutathione peroxidase and superoxide dismutase, but decreased malondialdehyde content. Compared with the SS-0.3 group, the SO-0.3 group showed augmented concentrations of total Se in milk and plasma, and total Se milk-to-plasma concentration ratio. In addition, increasing doses of HMSeBA linearly increased the concentrations of total Se in the milk and plasma. This study demonstrates that HMSeBA improves antioxidant status and increases milk and plasma Se concentrations more effectively than SS, indicating that HMSeBA could replace SS as an effective organic Se source for lactating dairy cows.

Total Selenium Quantification in Biological Samples by Inductively Coupled Plasma Mass Spectrometry (ICP-MS).

Selenium (Se) is an element readily absorbed during the intestinal tract, distributed in the body by means of blood and excreted mainly by urine or feces. Here, we describe the method allowing the determination of the total Se content in biological tissues and fluids by Inductively Coupled Plasma Mass Spectrometry (ICP MS).