Bioavailability Of Selenium Research Articles

Changes in selenium bioavailability in selenium-enriched paddy soils induced by different water management and organic amendments

Combined effects of water management and agricultural organic waste return on selenium (Se) bioavailability and mechanisms in Se-enriched paddy soils remain unclear. We investigated the effects of continuous flooding (CF) and alternating wet and dry (AWD), two types (cotton straw biochar [BC] and sheep manure [SM]) and concentrations (10 and 50 g·kg−1) of organic amendments on soil Se bioavailability, bacterial community structure in naturally Se-enriched soils (1.69 mg·kg−1). Results showed that 10 g·kg−1 SM treatment was the most effective in increasing Se bioavailability, especially under AWD treatment, whereas BC treatment reduced it. Compared with CF treatment, AWD treatment increased the Se content of root surface iron plaque and rhizosphere affinity for Se, and promoted the conversion of soil weakly organic matter bound Se to soluble-Se and exchangeable-Se. BC and SM addition significantly altered soil solution Fe(II), dissolved organic carbon, and soil bacterial community structure and function, including sulfur-oxidizing bacteria (Thiobacillus) and Se-reducing bacteria (Pseudarthrobacter), under different water management regimes. Notably, these bacteria showed a significant correlation with bioavailable Se. The present study provides theoretical guidance for agronomic practices in Se-enriched paddy soils.

Bioavailable Selenium Concentration and Bioavailability in Tissues of Beef Cattle.

The aim of the study was to compare the levels of bioavailable Se between different organs in beef cattle with regard to selenium status. The animals were divided into two groups based on serum selenium concentration, viz. normal and deficient Se status. Bioavailable selenium was extracted from the organs by simulated in vitro digestion, and its concentration was determined by spectrofluorimetry. The percentage of bioavailable Se was calculated in the liver, kidney, lung, spleen, heart, and longissimus dorsi muscle, based on the total Se content. In all animals tested, the highest bioavailable selenium concentrations were found in the kidney (0.175-0.408 µg/g) and the lowest in the longissimus dorsi muscle (0.04-0.042 µg/g), regardless of Se status. The highest bioavailability of Se was recorded in bulls, reaching 56.6% in the longissimus dorsi muscle, and the lowest in the kidney (21.4%). The study showed that cattle with Se deficiency had a higher percentage of bioavailable Se in their tissues than those with normal Se levels. This is most likely related to the fact that the body seeks to ensure optimal levels of the element in the organs during insufficient supply. Despite balanced feeding, there was a deficiency of Se. This is most likely related to the fact that, in plants, it occurs mainly in its inorganic form, which is less well-utilised by the animals and does not cover their needs for this element.

Ultrasonic-microwave assisted extraction of selenium-rich rice bran protein: A study on its structural and physicochemical properties

This study explores the effects of different extraction methods on the physicochemical properties and functional performance of selenium-rich rice bran protein (Se-RBP). Four extraction techniques—alkaline extraction (AAE), microwave extraction (MAE), ultrasonic extraction (UAE), and ultrasonic-assisted microwave extraction (UMAE)—were assessed for their efficiency and impact on protein structure, solubility, and functional properties, including emulsifying and foaming capacities. The results demonstrate that UMAE significantly enhances the functional properties of Se-RBP, achieving an emulsion stability index of 86.76% and a foaming capacity of 188.63%, both of which outperform the other methods. Furthermore, UMAE-treated Se-RBP exhibited a 35.43% increase in selenium bioavailability following gastrointestinal digestion. UMAE also delivered the highest antioxidant activity, reducing the IC50 for DPPH radical scavenging to 0.85 mg/mL. These improvements are attributed to UMAE's ability to achieve a finer, more uniform particle distribution and increased exposure of bioactive compounds. This study reveals the potential of UMAE in optimizing the extraction and functional utilization of Se-RBP.

The Chemical and Rheological Properties of Corn Extrudates Enriched with Zn- and Se-Fortified Wheat Flour

This paper analyzed the influence of the addition of Zn- and Se-fortified wheat flour to corn extrudates on viscosity, total starch content, starch damage, and bioavailability of zinc and selenium. Fortified wheat flour was added to corn grits in 90:10, 80:20, 70:30, and 60:40 ratios at three extrusion temperature profiles: 140/170/170 °C, 150/180/180 °C, and 160/190/190 °C. Viscosity values decreased significantly at different extrusion temperature profiles and at different proportions of wheat. The extrusion process increased the starch content, regardless of the extrusion temperature, and decreased it by adding different proportions of flour enriched with zinc and selenium. The starch damage increased with extrusion, without significant changes with extrusion temperature increment. The addition of different proportions of Zn- and Se-fortified wheat flour reduced starch damage values proportionally to the added content of enriched wheat. Increasing the temperature and the proportions, the total zinc content in the extrudates increased. Zinc bioavailability increased with increasing extrusion temperature. As for selenium, the total content increased by proportion increment but decreased with an increase in the extrusion temperature, though there were no significant differences in selenium bioavailability regardless of changes in extrusion temperature or the proportion of enriched wheat.

Selenoprotein P increases upon selenium and coenzyme Q10 supplementation and is associated with telomere length, quality of life and reduced inflammation and mortality

BackgroundSelenoprotein P (SELENOP) transports selenium to extrahepatic tissues and is a biomarker of selenium status. Low soil selenium leads to low dietary selenium intake. A consequence is an increased risk of cardiovascular disease. ObjectiveTo investigate clinical aspects associated with SELENOP deficiency, including biomarkers of inflammation, quality of life, and mortality within 12 years, and the effect of dietary selenium and coenzyme Q10 supplementation on SELENOP. MethodsSELENOP was determined at inclusion and after four years of supplementation in 403 elderly community-living participants low in selenium receiving selenium yeast (200 μg/day) and coenzyme Q10 (200 mg/day), or placebo. Pre-intervention, the average serum selenium level was 67 μg/L. T-tests, repeated measures of variance, Cox proportional regressions analyses, Kaplan-Meier graphs and ANCOVA analyses were applied. Associations with biomarkers of inflammation, telomere length, quality of life and mortality were investigated. Benchmark modelling was used to determine the serum selenium concentration at which the saturation levels of SELENOP and GPx3 was achieved. Comparison with GPx3 and serum selenium to identify increased mortality risk was performed, and the effect of supplementation on SELENOP levels were evaluated. ResultsInverse associations were observed between the level of SELENOP at inclusion and biomarkers for inflammation. At follow-up, shorter telomere lengths were seen in those with low levels of SELENOP at inclusion, whereas high levels of SELENOP were associated with better quality of life and decreased mortality. SELENOP had increased prognostic power compared to GPx3 and selenium. Saturation of SELENOP was achieved at a serum selenium level of 146 μg/L, and for GPx3 at 99 μg/L. Supplementation induced higher levels of SELENOP. ConclusionSignificant associations between SELENOP and inflammation, length of telomeres, quality of life, and mortality were observed. Thus, selenium supplementation improved SELENOP expression, thereby facilitating systemic selenium bioavailability and resulting in the observed positive health effects.

Selenium Discrepancies in Fetal Bovine Serum: Impact on Cellular Selenoprotein Expression.

Selenium is an essential trace element in our diet, crucial for the composition of human selenoproteins, which include 25 genes such as glutathione peroxidases and thioredoxin reductases. The regulation of the selenoproteome primarily hinges on the bioavailability of selenium, either from dietary sources or cell culture media. This selenium-dependent control follows a specific hierarchy, with "housekeeping" selenoproteins maintaining constant expression while "stress-regulated" counterparts respond to selenium level fluctuations. This study investigates the variability in fetal bovine serum (FBS) selenium concentrations among commercial batches and its effects on the expression of specific stress-related cellular selenoproteins. Despite the limitations of our study, which exclusively used HEK293 cells and focused on a subset of selenoproteins, our findings highlight the substantial impact of serum selenium levels on selenoprotein expression, particularly for GPX1 and GPX4. The luciferase reporter assay emerged as a sensitive and precise method for evaluating selenium levels in cell culture environments. While not exhaustive, this analysis provides valuable insights into selenium-mediated selenoprotein regulation, emphasizing the importance of serum composition in cellular responses and offering guidance for researchers in the selenoprotein field.

Mineralogy and Selenium Speciation Analysis of Early Cambrian Selenium-Rich Black Shale in Southern Shaanxi Province, China

Selenium (Se) is an essential trace element for humans and animals, and an excess of or deficiency in Se is harmful to health. Research on the selenium enrichment zone began in the late 1970s in Shuang’an, Ziyang, southern Shaanxi Province. Naore village is only one selenosis area in Shuang’an, Ziyang, China. Different scholars have conducted systematic studies on the occurrence of selenium, its organic geochemistry and biomarkers, and its content and enrichment patterns in this area. This study applied the TIMA (TESCAN integrated mineral analyzer) for the first time to conduct detailed mineralogical work. The minerals included quartz, carbonate minerals (calcite and dolomite), feldspar (plagioclase, albite, and orthoclase), biotite and muscovite, clay minerals (chlorite and kaolinite), hematite, pyrite, and accessory minerals (almandine, olivine, zircon, and apatite) in Naore village, Ziyang, Shaanxi Province. The ATi index (100 × apatite/(apatite + tourmaline)) is used to determine the source of heavy minerals and the degree of heavy minerals’ weathering. The content POS (100 × (pyroxene + olivine + spinel)/transparent heavy mineral) of olivine, pyroxene, and spinel in heavy minerals can reflect the contribution of basic and ultrabasic rocks in the source area. The ATi and POS indexes for the heavy minerals in the research area were 91.83~99.96 and 0.01~18.75, respectively, reflecting the abundance of volcanic rock material in their source. In addition, the migration, transformation, bioavailability, and toxicity of selenium in the environment are closely related to its species. The species of selenium in various selenium-rich areas (Naore, Wamiao, and Guanquan) mainly include unusable residues and organic forms, followed by humic-acid-bound selenium. The proportions of water-soluble, exchangeable, and carbonate-bound selenium are relatively small, and the proportion of Fe-Mn oxide-bound selenium is the lowest.

Selenium-Chelating Peptide Derived from Wheat Gluten: In Vitro Functional Properties.

The efficacy of selenium-chelating polypeptides derived from wheat protein hydrolysate (WPH-Se) includes enhancing antioxidant capacity, increasing bioavailability, promoting nutrient absorption, and improving overall health. This study aimed to enhance the bioavailability and functional benefits of exogenous selenium by chelating with wheat gluten protein peptides, thereby creating bioactive peptides with potentially higher antioxidant capabilities. In this study, WPH-Se was prepared with wheat peptide and selenium at a mass ratio of 2:1, under a reaction system at pH 8.0 and 80 °C. The in vitro antioxidant activity of WPH-Se was evaluated by determining the DPPH, OH, and ABTS radical scavenging rate and reducing capacity under different conditions, and the composition of free amino acids and bioavailability were also investigated at various digestion stages. The results showed that WPH-Se possessed significant antioxidant activities under different conditions, and DPPH, OH, and ABTS radical scavenging rates and reducing capacity remained high at different temperatures and pH values. During gastrointestinal digestion in vitro, both the individual digestate and the final digestate maintained high DPPH, OH, and ABTS radical scavenging rates and reducing capacity, indicating that WPH-Se was able to withstand gastrointestinal digestion and exert antioxidant effects. Post-digestion, there was a marked elevation in tryptophan, cysteine, and essential amino acids, along with the maintenance of high selenium content in the gastrointestinal tract. These findings indicate that WPH-Se, with its enhanced selenium and amino acid profile, serves as a promising ingredient for dietary selenium and antioxidant supplementation, potentially enhancing the nutritional value and functional benefits of wheat gluten peptides.

Fertilizer application alters cadmium and selenium bioavailability in soil-rice system with high geological background levels

The co-occurrence of cadmium (Cd) pollution and selenium (Se) deficiency commonly exists in global soils, especially in China. As a result, there is great interest in developing practical agronomic strategies to simultaneously achieve Cd remediation and Se mobilization in paddy soils, thereby enhancing food quality/safety. To this end, we conducted a field-plot trial on soils having high geological background levels of Cd (0.67 mg kg−1) and Se (0.50 mg kg−1). We explored 12 contrasting fertilizers (urea, potassium sulfate (K2SO4), calcium-magnesium-phosphate (CMP)), amendments (manure and biochar) and their combinations on Cd/Se bioavailability. Soil pH, total organic carbon (TOC), soil available Cd/Se, Cd/Se fractions and Cd/Se accumulation in different rice components were determined. No significant differences existed in mean grain yield among treatments. Results showed that application of urea and K2SO4 decreased soil pH, whereas the CMP fertilizer and biochar treatments increased soil pH. There were no significant changes in TOC concentrations. Three treatments (CMP, manure, biochar) significantly decreased soil available Cd, whereas no treatment affected soil available Se at the maturity stage. Four treatments (CMP, manure, biochar and manure＋urea＋CMP＋K2SO4) achieved our dual goal of Cd reduction and Se enrichment in rice grain. Structural equation modeling (SEM) demonstrated that soil available Cd and root Cd were negatively affected by pH and organic matter (OM), whereas soil available Se was positively affected by pH. Moreover, redundancy analysis (RDA) showed strong positive correlations between soil available Cd, exchangeable Cd and reducible Cd with grain Cd concentration, as well as between pH and soil available Se with grain Se concentration. Further, there was a strong negative correlation between residual Cd/Se (non-available fraction) and grain Cd/Se concentrations. Overall, this study identified the primary factors affecting Cd/Se bioavailability, thereby providing new guidance for achieving safe production of Se-enriched rice through fertilizer/amendment management of Cd-enriched soils.

Stratum affects the distribution of soil selenium bioavailability by modulating the soil physicochemical properties: A case study in a Se-enriched area, China

The soil selenium (Se) content and bioavailability are important for human health. In this regard, knowing the factors driving the concentration of total Se and bioavailable Se in soils is essential to map Se, enhance foodstuffs' Se content, and improve the Se nutritional status of humans. In this study, total Se and Se bioavailability (i.e., phosphate extracted Se) in surface soils (0–20 cm) developed on different strata were analyzed in a Se-enriched region of Southwest China. Furthermore, the interaction between the stratum and soil properties was assessed and how did the stratum effect on the concentration and spatial distribution of Se bioavailability in soils was investigated. Results showed that the median concentration of total Se in soils was 0.308 mg/kg, which is higher than China's soil background. The mean proportion of phosphate extracted Se in total Se was 12.2 %. The values of total Se, phosphate extracted Se, and soil organic matter (SOM) in soils increased with the increasing stratum age. In contrast, the coefficient of weathering and eluviation (BA) values decreased. The analysis of statistics and Geodetector revealed that the SOM, stratum, and BA were the dominant controlling factors for the contents and distributions of soil total Se and phosphate extracted Se. This study provided strong evidence that the soil properties that affected the total Se and Se bioavailability were modulated by the local geological background, and had important practical implications for addressing Se malnutrition and developing the Se-rich resource in the study region and similar geological settings in different parts of the globe.

Factors controlling accumulation and bioavailability of selenium in paddy soils: A case study in Luxi County, China

Selenium (Se) accumulation in rice (Oryza sativa L.) has become a major global concern. Se offers multiple health benefits in humans; however, its inadequate or excessive intake can be harmful. Therefore, determining the factors driving Se abundance and bioavailability in paddy soils is essential to ensure the safety of human Se intake. This study investigated the accumulation, bioavailability, and distribution of Se in 820 paddy soil and rice grain samples from Luxi County, China to assess how soil properties (soil organic matter [SOM], cation exchange capacity [CEC], and pH), geographical factors (parent materials, elevation, and mean annual precipitation [MAP] and temperature [MAT]), and essential micronutrients (copper [Cu], zinc [Zn], and manganese [Mn]) govern Se accumulation and bioavailability in paddy soils. Results showed that the average soil Se content was 0.36 mg kg−1, which was higher than that in China (0.29 mg kg−1). Alternatively, the average rice grain Se content was 0.032 mg kg−1, which was lower than the minimum allowable content in Se-rich rice grains (0.04 mg kg−1). Five studied parent materials all had a significant effect on soil Se content but had little effect on Se bioavailability (p < 0.05). CEC, elevation, and SOM, as well as the soil contents of Cu, Zn, and Mn were positively correlated with soil Se content, but pH, MAP, and MAT were negatively correlated. Correspondingly, Se bioavailability was negatively correlated with SOM and soil Zn content, but positively correlated with MAP and grain contents of Cu, Zn, and Mn. Furthermore, partial least squares path analysis revealed the interactive impacts of the influencing factors on Se accumulation and bioavailability in soils. On this basis, prediction models were established to predict Se accumulation and bioavailability in paddy soils, thereby providing theoretical support for developing efficient control measures to meet Se challenges in agriculture.

Amorphous structure and crystal stability determine the bioavailability of selenium nanoparticles

Microorganisms play a critical role in the biogeochemical cycling of selenium, often reducing selenite/selenate to elemental selenium nanoparticles (SeNPs). These SeNPs typically exist in an amorphous structure but can transform into a trigonal allotrope. However, the crystal structural transition process and its impact on selenium bioavailability have not been well studied. To shed light on this, we prepared chemosynthetic and biogenic SeNPs and investigated the stability of their crystal structure. We found that biogenic SeNPs exhibited a highly stable amorphous structure in various conditions, such as lyophilization, washing, and laser irradiation, whereas chemosynthetic SeNPs transformed into a trigonal structure in the same conditions. Additionally, a core-shell structure was observed in biogenic SeNPs after electron beam irradiation. Further analysis revealed that biogenic SeNPs showed a coordination reaction between Se atoms and surface binding biomacromolecules, indicating that the outer layer of Se-biomacromolecules complex prevented the SeNPs from crystallizing. We also investigated the effects of SeNPs crystal structures on the bioavailability in bacteria, yeast, and plants, finding that the amorphous structure of SeNPs determined Se bioavailability.

PSXIV-8 Comparison of the Effects of Hydroxy-Selenomethionine and Selenium-Enriched Yeast Against Hydrogen Peroxide-Induced Oxidative Stress in Rat Intestinal Epithelial Cells

Abstract Superior bioavailability of organic selenium (Se) has been extensively studied. However, limited research has been conducted to evaluate the effect of organic forms on intestinal redox potential to support gut health and animal well-being. Two experiments (Exp) were conducted to compare the effect of either hydroxy-selenomethionine (OH-SeMet) or Se-enriched yeast (Se-yeast) on ameliorating hydrogen peroxide (H2O2)-induced oxidative stress in a rat intestinal epithelial cell line (IEC-6). A cell viability test was initially performed to validate the Se level (0.15, 0.3, 0.6 ug/mL) used for the reactive oxygen species (ROS) assay. In both studies, OH-SeMet or Se-yeast promoted cell viability and attenuated cell apoptosis indicating no negative impact on cell growth. However, the Se-yeast sources showed considerably greater effectiveness than OH-SeMet. To quantify redox potential, confluent cells were treated with DCFDA, an indicator of ROS production. Briefly, IEC-6 cells were seeded into 96-well plates (4 ×104 cells per well) with 3 replicates per treatment (Trt) and incubated with a fresh solution of DCFDA. The ROS production, in response to 30µM H2O2, was quantified by fluorescence emission at 485 nm. Data were analyzed with GLIMMIX procedure of SAS. In both Exp, Se inclusion in all Se-Trts was 0.3 ppm. In Exp 1, Trts included: Non treated (cells only), H2O2, H2O2 + 2mM Trolox (Vit. E analog), H2O2 + sodium selenite, H2O2 + OH-SeMet, H2O2 + Se-yeast product A, H2O2 + Se-yeast product B. Cells treated with H2O2 had 4.6-fold increase (P &amp;lt; 0.05) in ROS production relative to non-H2O2 treated cells. Trolox reduced ROS 7.6-fold (P &amp;lt; 0.05) relative to H2O2 only cells, OH-SeMet and sodium selenite did not ameliorate (P &amp;gt; 0.35) the negative impact of H2O2 on ROS production. However, cells treated with H2O2 + Se-yeast product A or B reduced ROS production by 15% (P = 0.07) and 32% (P &amp;lt; 0.01), respectively, compared with cells treated with H2O2 only. To validate the redox potential of OH-SeMet, Exp 2 included a pure form of selenomethionine. Treatments in Exp 2. were similar to Exp 1 with the inclusion of H2O2 + seleno-L-methionine. Selenomethionine, either as a pure source or the hydroxy analog, did not prevent (P &amp;gt; 0.40) H2O2-induced oxidative stress. However, Exp 2 confirmed the effectiveness of Se-Yeast products on reducing ROS production. More specifically, Se-Yeast product B (52% reduction, P = 0.04) was superior to product A (32% reduction, P = 0.17) in comparison to cells treated with H2O2 only. These findings suggest that the type of organic Se source differs in their ability to regulate intestinal redox potential, with Se-yeast sources being more effective than hydroxy analogs. Selenomethionine content in Se-yeast does not appear to be the main driver in reducing ROS in intestinal cells, suggesting that livestock fed Se-yeast can support better intestinal health during oxidative stress.

Relative bioavailability of selenium in rice using a rat model and its application to human health risk assessment

Deficiencies of selenium (Se), a necessary microelement for humans, can be remedied by appropriately supplying Se-enriched rice. However, overconsumption of Se-enriched rice poses a potential risk. To accurately assess Se human health risks associated with Se-enriched rice consumption, we developed a rat in vivo model to systematically explore the relative bioavailability of Se (Se-RBA) from Se-enriched rice from a wide geographic range. Se concentrations were in the range of 0.06 ± 0.05 to 0.15 ± 0.15 mg kg−1, averaging 0.12 ± 0.11 mg kg−1, in 196 rice samples from 21 Chinese provinces, and selenomethionine (SeMet) was the dominant Se fraction (58.0–96.5%). The Se-RBA of Se-enriched rice calculated from urine ranged from 34.86% to 102.29%, averaging 62.27% (n = 12), and was positively correlated with the proportion of SeMet in rice (p < 0.05, R2 = 0.51). Furthermore, the Se intake calculated based on the Se-RBA indicated that the Se intake of consumers of Se-enriched rice was far less than the tolerable upper intake level. Thus, the limits established by law assume overestimates of the actual nutritional value of the Se content in Se-enriched rice, and it is important to consider Se bioavailability. The current study offers suggestions for future research and provides methods to reduce the uncertainty in estimating the health risks associated with Se intake from rice.

Physicochemical and microbiological parameters during the manufacturing of a beer-type fermented beverage using selenized Saccharomycesboulardii

Selenium is an essential trace element in human health. However, it has been considered a widespread selenium deficiency worldwide, although the recommended daily intake is very low (55 μg per day). Strategies have been implemented to comply with the recommended doses, for example, through bioavailable selenium such as selenoamino acids. Thus, this research aimed to elaborate on a beer-type fermented beverage produced with previously selenized Saccharomyces boulardii. For this, the yeast was selenized by adding a minimum inhibitory concentration of Na2SeO3 (74 ppm) to YPD media. Subsequently, barley must fermentations were carried out for 120 h. Kinetic parameters of the fermentation and physicochemical parameters and selenium content of the beverage were measured. The yeast accumulated up to 25.12 mg/g of dry cell. Furthermore, selenization affected the fermentation rate, but the beverage's physicochemical parameters were not different from those of the control. Due to the final concentration of selenium in the beverage (0.378 mg/kg), it is considered a process that confers advantages for the safe intake of selenium with bioavailable potential. In conclusion, fermented beverages enriched with organic selenium could be produced through cell selenization to produce functional beverages and food.

Simulation and prediction for the spatial heterogeneity of soil selenium bioavailability at different stratigraphic scales

Stratigraphic lithology strongly influences the spatial heterogeneity of soil available selenium (ASe), however, it is often neglected in regional simulation. Therefore, taking the Jiangjin District, where the soil is richer in selenium (Se), as the research area, the changes of soil ASe at different spatial scales have been simulated by combining Geodetector and three popular models (Multiple linear regression (MLR), Random forest (RF) and BP neural network (BPN)). The results showed that modelling with ‘Formation’ as the spatial scale could reduce the influence of stratum lithology difference on the spatial heterogeneity of soil ASe and improve the model's prediction accuracy. Compared with the MLR (R2 = 0.52, root mean squares error (RMSE) = 13.217 μg kg−1) and BPN (R2 = 0.55, RMSE = 13.79 μg kg−1), the RF (R2 = 0.67, RMSE = 10.85 μg kg−1) exhibited higher R2 and smaller RMSE, and the simulation effect of soil ASe is the best in the Middle Jurassic Shaximiao Formation (J2s). The outcomes of variable importance analysis revealed that soil total selenium (TSe) and soil organic matter (SOM) were the imperative factors for predicting ASe. The scenario simulation prediction showed that in the next 40 years, due to the combined influence of SOM and pH, the content of ASe in soil developed in the J2s would decrease from 40.8 μg kg−1 to 37.8 μg kg−1, a 7.8 percent drop. The main areas of soil ASe loss were in the western farming areas. The ASe content in dry land and paddy fields decreased by 12.0% and 4.9%, respectively. Therefore, long-term agricultural production activities would lead to soil ASe loss. The present results could provide a new scheme for the simulation and prediction of regional soil ASe, which is helpful for scientific planning, utilization of selenium-rich soil resources, and development of regional agricultural economy.

Supplementation of different sources of selenium on laying performance, egg quality traits, and shell calcification expressions in 50 weeks Lohmann Brown layer hen reproductive tract

Massive consumption and exportation of eggs in Malaysia are possible by maintaining and improving layer productive performances and egg quality through antioxidant supplementation such as selenium. The bioavailability of organic selenium in tissues resulted in a preference for organic selenium in poultry diets. The present study assesses the effects of feeding 50 weeks layer hens with sodium selenite, selenised yeast, and Stenotrophomonas maltophilia, ADS18 as a source of selenium and vitamin E on laying integrity, egg qualities, and reproductive gene expressions. The four different treatments (diets) used in the experiment were tagged as follows: Control: a basal diet containing 100 mg/kg vitamin E, SS: basal diet plus 0.3 mg/kg sodium selenite, Se-yeast: basal diet plus 0.3 mg/kg selenised yeast, and VADS18: basal diet plus 0.3 mg/kg ADS18. Productive performances were analysed throughout a 90-days of production. Eggs were collected biweekly, and egg qualities were measured. The uterine and magnum tissues were examined for the genes ovocleidin and ovocalyxin; OCX32, OCX36, OC17 and OC116. The results showed that Se-yeast significantly (P &lt; 0.05) increased laying integrity, while VADS18 supplementation significantly (P &lt; 0.05) increased egg weight. Supplementation of different selenium sources significantly (P &lt; 0.05) improved egg production and quality. Additionally, uterine gene expression was significantly (P &lt; 0.05) increased by VADS18 supplementation. Therefore, adding organic selenium to the diet maintained various laying performance indicators, egg qualities, and upregulated gene expression. Further evaluations are required to determine the optimum inclusion level of ADS18 poultry.

Effects of organic and inorganic selenium on selenium bioavailability, growth performance, antioxidant status and meat quality of a local beef cattle in China.

Selenium (Se) is an essential nutrient with multiple health benefits to humans and animals. Cattle generally require dietary Se supplementation to meet their daily requirements. The two main forms of dietary Se in cattle are organic Se and inorganic Se. Data comparing the health and productivity effects of organic Se and inorganic Se on cattle are still insufficient, and it is necessary to conduct more research to evaluate the bioavailability, nutritional value, deposition, and body functions of Se sources in different breeds and physiological stages of cattle raised in areas with different Se levels. The objectives of this study were to determine the effects of organic and inorganic sources of Se on plasma biochemical indices, Se bioavailability, deposition in body tissues and organs, growth performance, antioxidant capacity and meat quality of beef cattle raised in Se-deficient areas. Fifteen Chinese Xiangzhong Black beef cattle with an average weight of 254.5 ± 8.85 kg were assigned to three dietary groups. The three groups were fed the same basal ration and supplemented with either an inorganic [sodium selenite (SS)] or organic [selenomethionine (SM) or Se-enriched yeast (SY)] source of Se (0.1 mg/kg dry matter) for 60 days. At the end of the experiment, three cattle from each group were randomly selected and slaughtered, and samples were collected from tissues and organs for analysis. The results revealed that growth performance, slaughter performance, Se content of tissues and organs, meat quality characteristics including chemical composition, pH45min, pH24h, drip loss, and cooking losses did not differ (p > 0.05) due to supplementation of the different organic and inorganic sources of Se. SM and SY were more effective in increasing (p < 0.05) immunoglobulin M (IgM) concentrations in the blood and reducing (p < 0.05) malondialdehyde (MDA) content in the longissimus dorsi than SS. In conclusion, organic Se is more effective than inorganic Se in improving the immune and antioxidant capacity of Chinese Xiangzhong Black beef cattle.

SELENOP rs3877899 Variant Affects the Risk of Developing Advanced Stages of Retinopathy of Prematurity (ROP).

The significance of selenoproteins for the incidence of prematurity and oxidative-damage-related diseases in premature newborns is poorly understood. The latter are at risk for ROP as well as BPD, IVH, PDA, RDS, and NEC, which is particularly high for newborns with extremely low gestational age (ELGA) and extremely low birth weight (ELBW). This study evaluates the hypothesis that variation in the selenoprotein-encoding genes SELENOP, SELENOS, and GPX4 affects the risk of ROP and other comorbidities. The study included infants born ≤ 32 GA, matched for onset and progression of ROP into three groups: no ROP, spontaneously remitting ROP, and ROP requiring treatment. SNPs were determined with predesigned TaqMan SNP genotyping assays. We found the association of the SELENOP rs3877899A allele with ELGA (defined as <28 GA), ROP requiring treatment, and ROP not responsive to treatment. The number of RBC transfusions, ELGA, surfactant treatment, and coexistence of the rs3877899A allele with ELGA were independent predictors of ROP onset and progression, accounting for 43.1% of the risk variation. In conclusion, the SELENOP rs3877899A allele associated with reduced selenium bioavailability may contribute to the risk of ROP and visual impairment in extremely preterm infants.

Influencing Factors on Bioavailability and Spatial Distribution of Soil Selenium in Dry Semi-Arid Area

The chemical transformation of selenium (Se) in the topsoil, especially when regarded as low to sufficient Se (with high bioavailability) in dry arid environments, has great importance in the alkaline soils to yield Se-enriched food regionally. The Se content in the highly alkaline soil of the northwest region of China has inordinate agriculture economic potential, and such soil distribution is likely to produce Se-enriched crops with distinct features. One such large area of Zhongwei was investigated for the distribution of soil Se and its bioavailability, and the influencing chemical factors of soil total Se (T-Se) and bioavailable Se (B-Se) in the agroecosystem. The results suggested that the T-Se in Zhongwei soils (mg/kg) ranged from 0.01 to 0.55 with a mean of 0.2 ± 0.08, which was lower than the average Se distribution of both China (0.29 mg/kg) and the world (0.40 mg/kg). However, the overall B-Se proportion (16%) in T-Se was adequately higher than in other Se-rich soils. Spatial distribution depicted that the T-Se was specified as deficient in 42.6% and sufficient in 55.5% of the studied area, while Zhongning county was prominent with a higher B-Se proportion (22%) in the T-Se of Zhongwei. The influencing factors, such as pH and organic matter (OM), showed significant association with B-Se, as suggested by Pearson’s correlation and multiple linear regression (MLR). Furthermore, the vertical distribution of T-Se and B-Se was higher in agricultural soil (AS) than in natural soil (NS) and can be justified in the context of their association with OM. Based on these results, the Se-fortified crops can be yielded by practices to improve corresponding influencing chemical factors of soil, especially in dry areas.