Sodium Selenite Solution Research Articles

Biosafety and pharmacokinetic characteristics of polyethylene pyrrolidone modified nano selenium in rats

ObjectiveThis study aims to investigate the biocompatibility and pharmacokinetic characteristics of polyvinyl pyrrolidone-modified selenium nanoparticles (PVP-Se NPs). Understanding the biosafety of PVP-Se NPs is crucial due to their potential applications in mitigating oxidative stress-related diseases and improving drug delivery systems.MethodsSelenium nanoparticles were prepared using a sodium selenite solution, followed by PVP modification. Particle size analysis was conducted using dynamic light scattering (DLS), and particle morphology was observed using transmission electron microscopy (TEM). Different concentrations of PVP-Se NPs were intraperitoneally injected into SD rats, and the survival rate was observed. Liver and kidney tissues, urine, feces, and blood samples were collected at the highest safe dose, and the concentration of selenium ions was measured.ResultsThe average particle size of PVP-Se NPs was 278.4 ± 124.8 nm, exhibiting a semi-spherical shape. The maximum safe dose of PVP-Se NPs for intraperitoneal injection in rats was approximately 320 µg/kg. At this dose, the content of PVP-Se NPs significantly increased in the liver and kidney tissues from day 1 to day 3, in urine and feces during the first 8 h, and in blood during the first 2 h, followed by a gradual decrease.ConclusionWhen administered at a safe dose, PVP-Se NPs do not damage liver and kidney tissues and can be eliminated from the body through liver and kidney metabolism without accumulation.

Effect of Sodium Selenite Foliar Treatment on the Nutritional Quality of Cyclocarya paliurus (Batalin) Iljinsk

Cyclocarya paliurus (Batalin) Iljinskaja is a rare, endemic tree species in China. The leaves of C. paliurus contain a high concentration of biologically active compounds, and they are often used to make herbal tea. Exogenous selenium (Se) enrichment can promote the levels of active ingredients in C. paliurus. To explore the effects of exogenous Se enrichment, this study applied different concentrations of sodium selenite solution on the leaves (0, 40, 80, 120, 160, and 300 mg/L) and measured the changes in Se, secondary metabolites, soluble sugar, soluble protein, starch, and trace elements in the leaves at different treatment times. The results showed that with the increase in the concentration of sodium selenite spray, the selenium content in the leaves of C. paliurus gradually increased, and high selenium concentrations could cause seedling burning to the leaf surface (>160 mg/kg). When the selenium treatment concentration was 80 mg/kg, the selenium content reached the maximum value of the selenium-rich tea standard (4 mg/kg). The content of polyphenols and most elements reached their maxima under the treatment of 40 mg/L Na2SeO3, except for Mg and Mn, which peaked at 300 mg/L. The content of soluble sugars (38.1 mg/g) and starch reached their maxima under relatively high selenium treatment concentrations, whereas soluble protein (10.63 mg/g) exhibited its maximum value in the control group. The optimal harvest time was mainly concentrated in the 10–20 day treatment period. The objective of this research is to investigate the effects of exogenous selenium application on the nutritional quality of C. paliurus leaves. The findings will provide guidance for the effective cultivation of selenium-enriched Poria cocos as a medicinal and health-promoting product.

Preparation and structural characterization of selenium nanoparticles from Lactobacillus reuteri and their protective effects on DSS-induced ulcerative colitis in mice

In this study, selenium nanoparticles (SeNPs) with protection against dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) in mice were prepared extracellularly by co-culturing a sodium selenite solution with Lactobacillus reuteri. Multiple analytical techniques have shown that SeNPs are mainly composed of C, N, O, and Se elements and are spherical structures encapsulated by polysaccharides or proteins, with a diameter distribution of 70∼130 nm and a potential of approximately −25 mV. The results of cell experiments showed that the prepared SeNPs could significantly reduce the production of nitric oxide (NO) induced by lipopolysaccharide (LPS) in Raw264.7 cells and exert an anti-inflammatory effect by decreasing the levels of TNF-α and IL-1β and increasing the level of IL-10. Animal experiments demonstrated that the SeNPs could effectively alleviate symptoms, such as diarrhea, weight loss, bloody stool, colon shortening, and histopathological changes induced by DSS in mice. They could also reduce mucus damage, goblet cell depletion, and intestinal permeability. In addition, the prepared SeNPs could alleviate colitis by promoting the expression of tight junction proteins, occludin-1 and zonula occluden 1 (ZO-1) and inhibiting oxidative enzymes and pro-inflammatory factors, thereby protecting the barrier function. Analysis of intestinal microbiota revealed that the SeNPs could greatly modulate the gut microbiota in colitis, restore the normal levels of gut microbiota, and enhance immune regulation in mice, thereby inhibiting the further occurrence and development of UC.

Exploring the Anti-Inflammatory and Antioxidative Potential of Selenium Nanoparticles Biosynthesized by Lactobacillus casei 393 on an Inflamed Caco-2 Cell Line.

Selenium (Se) plays a crucial role in modulating inflammation and oxidative stress within the human system. Biogenic selenium nanoparticles (SeNPs) synthesized by Lactobacillus casei (L. casei) exhibit anti-inflammatory and anti-oxidative properties, positioning them as a promising alternative to traditional supplements characterized by limited bioavailability. With this context in mind, this study investigates the impact of selenium and L. casei in ameliorating inflammation and oxidative stress using a cell line model. The study is centered on the biosynthesis of selenium nanoparticles (SeNPs) by L. casei 393 under anaerobic conditions using a solution of sodium selenite (Na2SeO3) in the bacterial culture medium. The generation of SeNPs ensued from the interaction of L. casei bacteria with selenium ions, a process characterized via transmission electron microscopy (TEM) to confirm the synthesis of SeNPs. To induce inflammation, the human colonic adenocarcinoma cell line, Caco-2 was subjected to interleukin-1 beta (IL-1β) at concentrations of 0.5 and 25 ng/ml. Subsequent analyses encompass the evaluation of SeNPs derived from L. casei, its supernatant, commercial selenium, and L. casei probiotic on Caco2 cell line. Finally, we assessed the inflammatory and oxidative stress markers. The assessment of inflammation involved the quantification of NF-κB and TGF-β gene expression levels, while oxidative stress was evaluated through the measurement of Nrf2, Keap1, NOX1, and SOD2 gene levels. L. casei successfully produced SeNPs, as confirmed by the color change in the culture medium and TEM analysis showing their uniform distribution within the bacteria. In the inflamed Caco-2 cell line, the NF-κB gene was upregulated, but treatment with L. casei-SeNPs and selenium increased TGF-β expression. Moreover, L. casei-SeNPs upregulated SOD2 and Nrf2 genes, while downregulating NOX1, Keap1, and NF-κB genes. These results demonstrated the potential of L. casei-SeNPs for reducing inflammation and managing oxidative stress in the Caco-2 cell line. The study underscores the ability of L. casei-SeNPs to reduce oxidative stress and inflammation in inflamed Caco-2 cell lines, emphasizing the effectiveness of L. casei as a source of selenium. These insights hold significant promise for the development of SeNPs derived from L. casei as potent anti-inflammatory and anti-cancer agents, paving the way for novel therapeutic applications in the field.

Exogenous selenium mitigates cadmium uptake and accumulation in two rice (Oryza sativa L.) varieties in cadmium-contaminated soil

Rice grown in cadmium (Cd)-contaminated soil, is a potential threat to human health, but exogenous selenium (Se) application on rice can mitigate Cd toxicity. However, the mechanisms underlying Se mitigation of Cd stress in ratoon rice (RR) are still poorly understood. We conducted a pot experiment with moderate Cd-contaminated yellow–brown paddy soil on two rice varieties ‘Taoyouxiangzhan’ (TX) and ‘Liangyou 6326’(LY). For all treatments, 1.0 mg kg−1 sodium selenite solution was added to soil. Treatment T1 was sodium selenite only, and in the other treatments 100 mg L−1 Se solution was sprayed on the leaves at seedling stage (T2), at tillering stage (T3), and in early anthesis stage (T4). Se treatments decreased Cd accumulation in rice grains and herbage. Under foliar spraying 100 mg L−1 Se at the seedling + 1.0 mg kg−1 Se in soil (T2), leaf Cd content decreased 16.95% in the current season and grains content decreased 46.67% in the subsequent season. Furthermore, grain Se content increased 0.94 mg kg−1 for the TX variety combined with the analysis of Cd bio-accumulation factor in grains, and Se treatments effectively decreased Cd grain concentrations due to reduced Cd translocation from roots to grains. TX variety rice showed a more pronounced response to Se treatments than LY.

Foliar application of sodium selenite affects the growth, antioxidant system, and fruit quality of strawberry.

Selenium (Se) plays a vital role in various physiological processes in plants and is regarded as an essential micronutrient for human health as well. In this study, sodium selenite solution at 10, 40, 70, and 100 mg·L-1 concentrations was foliar sprayed, and the strawberry plant growth, antioxidant system, and fruit quality with an emphasis on sugar and acid content were assessed. The results showed that 10 mg·L-1 of sodium selenite treatment promoted plant growth, while all the treated concentrations could enhance photosynthesis, the antioxidant system in leaves, the content of Se, and ascorbic acid in fruits. More importantly, 40 mg·L-1 sodium selenite treatment significantly increased fruit weight, total soluble solid, total phenolic content, and anthocyanins, as well as improved the shape index. Furthermore, it decreased the total flavonoid and proanthocyanidin content. Particularly, sodium selenite treatment at 40 and 70 mg·L-1 largely increased the ratio of soluble sugars to titratable acid. The changes of predominant sugars and organic acids during fruit development were further investigated. The sucrose, fructose, and glucose content was upregulated by sodium selenite treatment through upregulating the activities of sucrose phosphate synthase (SPS) and acid invertase, as well as the FaSPS expression. In addition, sodium selenite treatment inhibited the activity of citrate synthase and phosphoenolpyruvate carboxylase, rather than modulating their transcript levels to reduce the citric acid content. This work presented a potentially efficient approach to enhance plant growth and fruit quality and supplement Se in strawberry, providing insights into the mechanism of regulating sugar and acid metabolism by Se.

Green synthesis and anti‐biofilm effect on Drosophila melanogaster of selenium nanoparticles from Vitis vinifera for photocatalytic degradation and different biological applications

AbstractThis study aims to combine Vitis vinifera extract with sodium selenite (Na2SeO3) solution to develop a biobased approach for producing green selenium nanoparticles. V. vinifera fruit extract is potent in secondary metabolites such as phenols (1.19 mg gallic acid equivalents/g), flavonoids (0.42 mg catechin equivalents/g), and tannins (2.84 mg tannic acid equivalents/g), it was discovered to be particularly appropriate for the production of nanoparticles. SeNPs were characterized using UV–vis, SEM, zeta potential, EDS, DLS, FTIR, and XRD AFM. SeNPs were assessed for anti‐microbial, anti‐biofilm, and antioxidant assay. Biosynthesized‐produced SeNPs were discovered to possess significant antioxidant activity and high antibacterial action. Selenium nanoparticles had the potential to modulate the impact of Pseudomonas aeruginosa on Drosophila melanogaster. Molecular analyses were performed, and survival analysis curves were plotted to study the impact of SeNPs. When SeNPs are exposed to UV light, they efficiently break down crystal violet dye. To comprehend the impact of three variables—pH, time, and SeNP concentration—on the dye degradation, a full factorial design was employed. This study showed that SeNPs can be used as a potential anti‐biofilm agent and are also effective in the textile, dye, and pharmaceutical industries.

Three accelerated methods based on microwave, hydrothermal and conventional heating in the green synthesis of selenium nanoparticles using garlic aqueous extract: Screening and characterization

Selenium nanoparticles (Se NPs) have unique biological characteristics, including anticancer, antioxidant and antimicrobial activities. Furthermore, the green synthesis of Se NPs using plant extracts, due to their natural reductant and stabilizer molecules, can intensify the process with minimal toxic effects on the human body and the environment. Se NPs have been synthesized using an aqueous extract of garlic and three accelerated heating methods based on microwave (800 W for 2.5 min), hydrothermal (temperature and pressure of 121 ºC and 1.5 atm, for 15 min) and conventional (at 150 ºC for 1 h) heating using a heater with stirring. Solution mixtures containing 20 mL of the prepared extract and 5 mL of sodium selenite solution (10 mM) were exposed to these three mentioned heating methods. Fourier transform infrared spectroscopy, UV-Vis spectrophotometry, dynamic light scattering analysis and transmission electron microscopy were used to assess characteristics of the formed Se NPs. The results showed that the fabricated Se NPs via microwave, autoclave and conventional heating methods had minimum particle size (107 nm) and polydispersity index (0.155), and maximum zeta potential (-38.7 mV) values. Furthermore, the spherical formed Se NPs using garlic extract and under microwave, conventional and autoclave heating methods had antioxidant activity of 44.2, 34.8 and 32.6 %, respectively. The formed Se NPs also indicated high antibacterial activity toward Escherichia coli and Staphylococcus aureus bacteria strains.

Antioxidant Effects of Selenium Nanoparticles Prepared from Eruca Sativa Extract on Ketoconazole –Induced Testicular Oxidative Damage in Male Rats

Background: Recent studies have shown that the anti-fertility effects of Ketoconazole can be minimized by taking an antioxidant nanoparticles based-plant extract in combination with the medication or by taking it after medication. One of the effective methods to improve its medicinal properties and decrease the toxicities of Selenium is by formulating it as nanoparticles. However, this is still a challenging strategy. Objectives: The aim of this study was to analyze the impact of nano selenium, which was prepared from Eruca Sativa extract, on testicular oxidative stress parameters in rats that were treated with ketoconazole. The study will focus on the evaluation of glutathione peroxidase, superoxide dismutase, and malondialdehyde as indicators of oxidative stress. Methods: In this study, a 1% w/v solution of plant extract was added to a solution of 10mM sodium selenite in different ratios, and placed on a magnetic stirrer in the dark for 12 hours at a temperature 50Cº and pH9. The solution was then left for 48 hours, and the optimal fabricated selenium nanoparticles were selected for further characterization. forty-eight rats were divided into six groups with eight animals in each. Group A was the negative control, while Group B was given oral Ketoconazole at a dose of 50mg/kg for fourteen days. Group BC, BD, BE1 and BE2 were given oral Ketoconazole at a dose of 50 mg/kg for fourteen days, followed by 200mg/kg Eruca Sativa, 0.5mg/kg oral sodium selenite, 0.25mg/kg oral nano selenium and 0.5mg/kg oral nano selenium for 28 days, respectively. Finally, the animals were euthanized and their testicle anti-oxidant parameters were evaluated. Results: Significant increases in glutathione peroxidase and superoxide dismutase ( p value < 0.001), and a decrease in malondialdehyde levels ( p value < 0.001) were observed in groups treated with nanoparticles compared to control group. Conclusion: Nano forms of prepared by Eruca sativa extract exhibit significant antioxidant effects on testicular tissues, while being available for several metabolic, biological, and physiological functions.

The influence of microelements on the yield and its quality of wheat grown under drought conditions on soil with different phosphorus supplies

The results of 2-year vegetation studies devoted to the study of the existing prerequisites for treating seeds (PTS) with solutions of flax selenium, vanadium, tungsten and iodine on the yield and its structure, as well as indicators of the quality of wheat grain are presented. The experimental crop was grown on soil with different supplies of available phosphorus and was grown in an artificially created drought. The effectiveness of microelements was most realized under conditions of low phosphate content in the soil. The use of solutions of sodium selenite, ammonium vanadate, ammonium tungstate and potassium iodide helps to increase the weight of wheat grain by 14, 11, 13 and 7% relative to seed treatment with distilled water. Under stress conditions, persistent sodium selenite has the best effectiveness - grain increase of 11%.

Green synthesis of selenium nanoparticles using leaf extract of Moringa oleifera, their biological applications, and effects on the growth of Phaseolus vulgaris-: Agricultural synthetic biotechnology for sustainable nutrition

This research aims to design an eco-friendly approach for synthesizing green Selenium nanoparticles by mixing the leaf extract of Moringa oleifera and Sodium Selenite solution. The Selenium nanoparticles were characterized using UV–vis, FTIR, XRD and SEM, EDS, DLS, Zeta potential, and AFM. SeNPs were assessed for anti-microbial, anti-biofilm, and antioxidant assay. The analysis of X-ray diffraction reveals that Selenium NPs are 71.2 nm with a crystallinity of 66.8%. The band gap energy shows 2.4eV. Green-produced SeNPs were discovered to have high antibacterial action as well as significant antioxidant activity (IC50-50.21 μg for DPPH, 50.06 μg for ABTS, 62.9 μg for FRAP). SeNPs degrade crystal violet dye effectively when exposed to UV radiation. SeNPs were very effective against the biofilm formation by Pseudomonas aeruginosa, it was able to cease its growth to the maximum compared to the other bacterial strains. The full factorial method was followed to understand the consequences of three variable factors that is pH, time, and concentration of the SeNPs on the dye degradation. The concentration and pH were significant which influenced the dye degradation. Apart from this Selenium nanoparticles were able to influence the growth of Phaseolus vulgaris by increasing the amount of chlorophyll, tannin, flavonoid, and phenol in the plant grown in the presence of selenium compared to the control. The morphological characteristics of the plant were seen to be influenced by the selenium. Molecular analysis was also performed to study the change in the DNA content and the protein content. We conclude that SeNPs can be used by agro-based industries and textile dye industries.

Screening the possible effect of a phytofabricated nanoselenium-composite from Eruca sativa extract in reducing infertility in males

The antifertility effects of ketoconazole can be avoided or diminished by administering nano-selenium-based-antioxidant plant extract simultaneously or sequentially. Using selenium as nanoparticles (SeNPs) is one of the essential methods for enhancing its therapeutic effects and lowering toxicities. This study aimed to analyze the changes made to the parameters of androgens, such as testosterone and gonadotropin hormones: luteinizing hormone and follicle stimulating hormones together with sperm indexes after administration of antioxidant phytofabricated nanoselenium to mitigate oxidative damage brought on by ketoconazole. In brief, 1% weight-per-volume of the extract was loaded into a solution of 10 mM sodium selenite in various ratios on a magnetic stirrer (50 °C, PH 9) in the dark for 12 hours, left for 48 hours and then sent for characterization, which was performed using ultraviolet-visible spectroscopy (UV-vis spectra), Fourier transform infrared spectroscopy (FTIR), and dynamic light scattering (DLS). Then after the selection of the solution containing the optimal fabricated selenium nanoparticles it was administered to three groups out of seven groups of albino rats with eight animals in each one as follows: Gr. A negative control (no treatment), Gr. B oral ketoconazole 50 mg/kg for fourteen days, Gr. BC, BD, BE1, BE2 and BE3; each one received oral ketoconazole 50 mg/kg for fourteen days followed by: 200 mg/kg Eruca sativa (Gr. BC), 0.5 mg/kg oral sodium selenite (Gr. BD), 0.5 mg/kg/cm2 skin area local nanoselenium (Gr. BE1), 0.25 mg/kg oral nanoselenium (Gr. BE2) and 0.5 mg/kg oral nano selenium (Gr. BE3) respectively for 28 days. After this period, the animals were anesthetized, and plasma testosterone, luteinizing, and follicle stimulating hormones were assessed using Elisa Kit; after that, they were euthanized, and the epididymis of the right testis was carefully removed for evaluation of sperm indices (count, viability, abnormality, and motility). The reduction of selenium ions into PF-SeNPs induced by Eruca sativa extracts at a ratio of (1:2) (Na2SeO3: Eruca sativa) solution was confirmed by the gradual conversion of colour from dark brown to light yellow and then to reddish-orange after the addition of acidic sodium selenite solution and reacting for 12 h. The final reddish-orange colour is the most significant property of nanoparticles. In UV-vis spectroscopy, a strong absorption peak appeared between 268–964 nm with maxima at 268 nm, confirming the formation of nanoselenium. The optimal phytofabricated nanoselenium particles were obtained with a spherical shape, highly stable, and the smallest in size (39.4 nm in diameter) as proved by DLS with Poly Dispersity Index of 0.242 and zeta potential value of –56.57 mV. In the current study, testicles were damaged by administering ketoconazole at a dose of 50 mg/kg/day orally for 14 days. This testicular damage was linked to significant reductions in testosterone levels, elevated levels of LH and FSH, and significant decreases in sperm count, motility, and viability, which in turn affected spermatogenesis. Concurrently, the administration of Eruca sativa extract, sodium selenite and nanoselenium solution (in different doses and routes) following ketoconazole was shown to significantly improve biochemical parameters. These improvements included an increase in testosterone levels with little to no impact on LH and FSH levels as well as improved sperm indices. Additionally, the oral nanoselenium groups in 0.25 and 0.50 mg/kg produced the best outcomes with only minor differences between them. In conclusion, the antioxidant effects of the phytofabricated nanoselenium-based Eruca sativa leaf extract considerably improved testicular tissues.

Effects of High Doses of Selenate, Selenite and Nano-Selenium on Biometrical Characteristics, Yield and Biofortification Levels of Vicia faba L. Cultivars.

Faba bean (Vicia faba L.) has spread worldwide as an excellent source of proteins. To evaluate the efficiency of Se biofortification, four cultivars of V. faba (Belorussian, Russian Black, Hangdown Grünkernig, and Dreifach Weiβe) were foliar treated with 1.27 mM solutions of nano-Se, sodium selenate, and sodium selenite. Yield, protein, and Se contents were greatly affected by genetic factors and chemical form of Se. Selenium biofortification levels were negatively correlated with Se concentration in control plants and increased according to the following sequence: nano-Se < sodium selenite < sodium selenate. Contrary to selenate and selenite, nano-Se showed a growth-stimulating effect, improving yield, seed weight, and pod number. Pod thickness decreased significantly as a result of nano-Se supply and increased by 1.5-2.3 times under selenate and selenite supply. The highest Se concentrations were recorded in the seeds of Se-fortified cv. Belorussian and the lowest one in those of Se-treated Hangdown Grünkernig. Protein accumulation was varietal dependent and decreased upon 1.27 mM selenate and selenite treatment in the cvs. Hangdown Grünkernig and Dreifach Weiβe. The results indicate the high prospects of nano-Se supply for the production of faba bean seeds with high levels of Se.

Unveiling the mechanisms of aroma metabolism in selenium-treated broccoli through transcriptome sequencing analyses

The current study aimed to investigate the impacts of selenium (Se) treatment on the volatile aroma compounds of broccoli heads, and to understand the underlying mechanisms of aroma substances metabolism. To accomplish this, the dynamic changes of ethylene release rate, respiratory intensity, weight loss rate, and volatile compounds were determined in broccoli heads treated with a 2 mg L−1 sodium selenite solution for 50 days. RNA sequencing (RNA-seq) was conducted on samples taken at 10, 20 and 40 days to uncover the molecular mechanisms of the synthesis and metabolism of aroma substances in broccoli heads. The results showed that Se treatment decreased the release rate of ethylene, respiratory intensity, and weight loss rate. Additionally, an increase in the content of volatile aroma compounds in broccoli heads treated with Se was observed through GC-IMS technique. Aldehydes, esters, and alcohols were found to constitute the majority of these volatile aroma compounds. RNA-seq analysis identified 56,130 transcripts and revealed 524, 1943, and 2274 differentially expressed genes (DEGs) in the Se10d vs. CK10d, Se20d vs. CK20d, and Se40d vs. CK40d groups, respectively. These expression transcripts of volatile aroma substance metabolism were found to be enriched in related pathways, including glycolysis, pyruvate metabolism, fatty acid metabolism, transcription factors, and aromatic amino acid metabolism. In conclusion, this study not only enhances our understanding of selenium's mechanism of action but also has implications for the application of selenium in vegetable preservation.

The Physiological and Molecular Responses of Exogenous Selenium to Selenium Content and Fruit Quality in Walnut

To study the effect of exogenous selenium on fruit quality in walnut (Juglans regia L.), 8-year-old walnut (Qingxiang) was taken as the research object. In the fruit expansion stage, 300 mg/L of sodium selenate, yeast selenium and sodium selenite solutions were applied on the leaf of walnut, and the selenium levels in leaves, pericarp and kernel were determined at the ripening stage. The fruit quality, mineral nutrient content, antioxidant enzyme activity, and related genes’ expression were analyzed. The results showed that the three exogenous selenium increased the selenium levels in leaves, pericarp and kernel of walnut. They also significantly increased fruit and kernel weights, and kernel linoleic acid, but markedly decreased kernel crude fat and saturated fatty acid. Selenium spraying promoted the absorption of mineral nutrients such as potassium and zinc, but inhibited the absorption of calcium, and had no significant effect on iron and magnesium in the kernel. Three exogenous selenium increased the activities of superoxide dismutase (SOD), peroxidase (POD), ascorbate peroxidase (APX), and catalase (CAT) significantly in the kernel. Except for sodium selenate treatment significantly reduced malondialdehyde (MDA) content in the kernel, the other two selenium sources treatments had no significant effect on MDA and hydrogen peroxide (H2O2) levels. They also increased the expression of JrCu/Zn-SOD, Jr2-Cys POD, JrCyt-APX and JrCAT in kernel, to different extents. These implies that, in the walnut fruit enlargement period, the foliar spraying selenium could increase the selenium content of walnut, affect the mineral nutrient absorption, improve the antioxidant capacity and related genes’ expression, and reduce the degree of peroxide, and then improve the quality of fruit. Furthermore, yeast selenium showed the comprehensive effect of the best.

Toxicity monitoring signals analysis of selenite using microbial fuel cells

Microbial fuel cells (MFCs) based biosensors are widely studied to environmental monitoring. The suitable responsive signal is important for microbial electrochemical sensors. However, the responsive signals of toxins have not been investigated in detail. Using sodium selenite as a toxic substance, the different response signals are analyzed over a concentration range from 0 to 150 mg/L in the double chambered. The output voltage and power density had the opposite trend between 0 and 2.5 mg/L and 2.5–150 mg/L. To analyze the reasonable signal of Se(IV) monitoring sensor, correlation analysis of concentrations and responsive signal data (maximum voltage, maximum power density, coulombic recovery, coulombic efficiency, and normalized energy recovery, etc.) has been accomplished. The high concentration of exogenous selenite (2.5–100 mg/L) is negatively correlated with maximum voltage (r = −0.901, p < 0.01) and max power density (r = −0.910, p < 0.01). The low concentration of exogenous selenite is positively correlated with average voltage, max power density, coulombic yield (r = 0.973, 0.999 and 0.975, respectively. p < 0.05). Furthermore, Illumina sequencing results indicate that the addition of sodium selenite solution changes the anode community structure, thereby affecting the removal efficiency of organic matter, which may be the reason why coulombic efficiency and normalized energy recovery are not suitable as sensing signal. Overall, based on the analysis of experimental data, the maximum power density is the best response signal, which provides a reference for the selection of sensor response signal based on microbial fuel cells.

Effects of selenium solution on the crystalline structure, pasting and rheological properties of common buckwheat starch.

Selenium is an important element that affects human growth and development, and also affects the yield and quality of common buckwheat. In our study, two common buckwheat varieties were sprayed with different concentrations (0 g/hm2, 5 g/hm2, 20 g/hm2) of sodium selenite solution at the initial flowering period and the full flowering period, respectively, to determine the effects of selenium solution on the physicochemical properties of common buckwheat starch. With increasing selenium levels, the amylose content, peak viscosity, breakdown, relative crystallinity, pasting temperature and gelatinization enthalpy first decreased and then increased, while the transparency showed a trend of increasing and then decreasing. All samples exhibited a typical A-type pattern, while at high selenium level, the degree of short-range order of common buckwheat starches changed. From the rheological properties, it can be seen that the starch paste is dominated by elastic properties, while the low selenium treatment decreases the viscosity of the starch paste. These results showed that spraying different concentrations of selenium solutions at different periods significantly affected the physicochemical properties of common buckwheat starch.

Enhancing organic selenium content and antioxidant activities of soy sauce using nano-selenium during soybean soaking.

Nano-selenium has a greater potential than inorganic selenium in preventing selenium-deficiency diseases due to its higher safety. In this study, spherical nano-selenium particles (53.8 nm) were prepared using sodium selenite, ascorbic acid and chitosan. Selenium-enriched soy sauces were prepared by soaking soybean in nano-selenium and sodium selenite solutions (2–10 mg/L), respectively. Total selenium and organic selenium contents of soy sauces prepared by nano-selenium and sodium selenite were increased by 32–191-fold and 29–173-fold compared to the control (without selenium), and organic selenium accounted for over 90% of total selenium. Soy sauce prepared using 6 mg/L nano-selenium had the strongest antioxidant activities, which were 9.25–28.02% higher than the control. Nano-selenium (6 mg/L) markedly enhanced the koji's enzyme activities (9.76–33.59%), then the latter promoted the release of total phenolics (27.54%), total flavonoids (27.27%) and the formation of free amino acids (16.19%), Maillard reaction products (24.50%), finally the antioxidant activities of selenium-enriched soy sauce were enhanced.

Participation of low molecular weight antioxidants selenium and caffeic acid in the regulation of respiration in Solanum Tuberosum in hypothermic conditions

To study the effect of low molecular weight antioxidants on the respiration process, the content of auxins and abscisic acid, 15-day-old potato (Solanum tuberosum) tubers grown under laboratory conditions were sprayed with 5.8 μM sodium selenite solution or 0.1 mM caffeic acid solution. Control runners were treated with water. Hypothermia (-2 °C) simulating freezing was created for 2 hours. 21-day-old runners were analyzed. Under optimal temperature conditions, the studied antioxidants stimulated the respiration process, while selenite had a greater effect. Caffeic acid increased the maintenance respiration rate. Selenite and caffeic acid increased the auxin content in the runners. Selenite reduced the amount of abscisic acid, resulting in an increase in the indoleacetic acid/abscisic acid ratio. Under hypothermic conditions, caffeic acid significantly reduced the increase in respiration, and in the option with selenite, an insignificant stabilization of this process was noted with a greater decrease in indoleacetic acid/abscisic acid ration as compared with optimal conditions.

Yield and quality of Dega white lupine grain (Lupinus Albus) and yubileynaya 80 spring wheat (Triticum Aestivum L.) depending on the application method of sodium selenite.

In 2017-2019, we conducted the field and vegetation experiments at the field station of Russian State Agrarian University, Moscow Timiryazev Agricultural Academy to study the effect of sodium selenite on the yield and grain quality indicators of white lupine, Dega variety, and spring wheat, Yubileynaya-80 variety. The best way found to use selenium is to spray vegetative plants with 0.01% aqueous sodium selenite solution. The studies have shown an increase in grain yield by 15-17%, crude protein content by 9-15% and crude fat content by 5-7% when treated with sodium selenite. The obtained grain yield of white lupine has a higher feed and nutritional value and is suitable for feeding animals and preparing various types of feed and feed additives. The optimal way to use selenium is spraying vegetative plants before shooting. Treatment with sodium selenite contributes to an increase in wheat yield by 1.5 times. We have established the positive effect of sodium selenite on the quality indicators of wheat grain. An increase in the content of raw gluten and glassiness of grain has been noted, which determines high bread-making qualities.