Search Results (337)

This study explores the dual effects of selenium (Se) supplementation on silkworm development by analyzing miRNA expression profiles of fat bodies in silkworms under different Se concentrations (50 µM and 200 µM). Compared to the control, 84 miRNAs displayed different expression levels in the F_50 µM group, with 72 miRNAs up-regulated and 12 down-regulated; 152 miRNAs were differentially expressed in the F_200 µM group, with 124 up-regulated and 28 down-regulated. In the F_50 µM group, the target genes of differentially expressed miRNAs were mainly enriched in Toll and Imd signaling pathways, oxidative phosphorylation, and ribosome biogenesis in eukaryotes; however, mainly oxidative phosphorylation, ribosome biogenesis in eukaryotes, and the spliceosome were enriched in the F_200 µM group. Based on the results of the protein–protein interaction network and miRNA-target network, bmo-miR-2a-1-5p and bmo-miR-317-3p_L-2R+2 were screened as key miRNAs in the F_50 µM group and the F_200 µM group, respectively. The bmo-miR-2a-1-5p mainly targeted 10014128 (DREDD), 100862750 (ATF2), and 101744000 (Tak1) genes, which were enriched in Toll and Imd signaling pathways. The bmo-miR-317-3p_L-2R+2 primarily regulated 101738508 (SF3b) and 101746688 (Prp19) genes, which were in the spliceosome pathway. Thus, our results demonstrated that Se supplementation improved the silkworm development via bmo-miR-2a-1-5p miRNA regulation of the Toll and Imd signaling pathways and inhibited it via bmo-miR-317-3p_L-2R+2 miRNA targeting the spliceosome pathway. Our data revealed that 50 µM Se supplementation could improve silkworm productivity; meanwhile, a 200 µM Se treatment displayed toxic effects, leading to impaired development. Full article

Selenium is an essential trace element for human health, but it mainly exists in an inorganic form that cannot be directly absorbed by the body. Brewer’s yeast efficiently converts inorganic selenium into bioavailable organic selenium, making selenium-enriched yeast highly significant for human health research. Selenomethionine (SeM) is an important indicator for evaluating the quality of selenium-enriched yeast. Brewer’s yeast was selected as the experimental subject, and the digestion of this yeast (Brewer’s yeast) was simulated using an in vitro biomimetic gastrointestinal reactor to evaluate the effects of selenium-enriched yeast with various SeM levels on the gut flora of a healthy population. The experimental design comprised normal yeast (control group, OR), yeast containing moderate SeM levels (selenium-enriched group, SE), yeast containing high SeM levels (high-selenium group, MU), and a commercially available group comprising selenium-enriched yeast tablets (MA). The MU group exhibited a significantly higher concentration of short-chain fatty acids than the OR and MA groups during 48 h of fermentation, with significant differences observed (p < 0.05). Sequencing results revealed that the MU group showed significantly increased relative abundances of Bacteroidetes and Actinobacteria, while exhibiting a decreased ratio of Firmicutes to Bacteroidetes, which may simultaneously affect multiple metabolic pathways in vivo. These findings support the theory that selenium-enriched yeast with a high SeM has a more positive effect on human health compared with traditional yeast and offer new ideas for the development and application of selenium-enriched yeast. Full article

Selenium (Se) is an essential trace element for humans, and the production of Se-enriched rice (Oryza sativa) is a key approach for Se supplementation. Nevertheless, the effects of different Se forms and concentrations on the metabolism and aboveground absorption pathways of rice seedlings are not yet well-understood. Therefore, we conducted a hydroponic experiment and used transcriptome analysis to study the absorption and transformation processes of sodium selenite (Na₂SeO₃) and selenomethionine (SeMet) in rice at the seedling stage. The aboveground (stem + leaf) Se concentration at the seedling stage was higher under the SeMet treatments, and low Se applications (<25 μM) significantly promoted rice growth. Selenocysteine (SeCys) and SeMet were the primary forms of Se in rice, accounting for 57–86.35% and 7.6–31.5%, respectively, while selenate [Se (VI)] significantly increased when Se levels exceeded 25 μM. In the transcriptome, differentially expressed genes (DEGs) were significantly enriched in the following pathways: carbon metabolism, amino acid biosynthesis, and glutathione metabolism. In the Na₂SeO₃ treatments, genes encoding phosphoglycerate mutase (PGM), triosephosphate isomerase (TPI), phosphofructokinase (PFK), pyruvate kinase (PK), malate dehydrogenase (MDH), polyamine oxidase (PAO), aspartate aminotransferase (AST), and glutathione S-transferase (GST) were upregulated, and the expression levels of differentially expressed genes (DEGs) decreased with increasing Se levels. SeMet treatments upregulated genes encoding PFK, PK, glutamine synthetase (NADH-GOGAT), and L-ascorbate peroxidase (APX), and expression levels of DEGs increased with increasing Se levels. This study provides important insights into the molecular mechanisms of the uptake and metabolism of different Se forms in rice at the seedling stage. Full article

Selenium-enriched sweet maize is an important product to alleviate selenium deficiency in the human body. In this study, the effects of the basal application of selenium fertilizer on the selenium content and yield of maize were analyzed in a 2-year field trial using a two-factor, five-level, split-area experimental combination design with a different selenium fertilizer application rate (150–750 kg ha⁻¹) and depth (1–20 cm). It was found that the selenium application rate and depth significantly affected dry matter mass, selenium content, and selenium accumulation in maize. In particular, the Se3D4 treatment combination (a selenium application rate of 450 kg ha⁻¹ and depth of 15 cm) performed the best in increasing the selenium content and yield of the maize grain. The 2-year data showed that the selenium content of maize grain under Se3D4 treatment reached 3.59 mg kg⁻¹ and 3.24 mg kg⁻¹, which were 13.63 and 13.70 folds as the control, respectively, and the yield reached 6.28 t ha⁻¹ and 6.07 t ha⁻¹, which were 24.35% and 33.30% higher than the control, respectively. Therefore, by optimizing the application rate and depth of selenium fertilizer, the selenium content and yield of maize can be significantly increased. The results of this study provide a theoretical basis for the precise application of selenium fertilizer in the biofortification of sweet maize. Full article

Geometric and mechanical analyses were performed on 82 selenium-rich eggs, which underwent hydrostatic testing as 2 raw eggs, 60 steamed eggs, and 20 emptied eggshells. By analyzing the geometric and mechanical properties of the egg, we can draw inspiration from its structural design to create a pressure shell capable of effectively withstanding the immense water pressure in deep-sea environments. The major axis, minor axis, egg-shape coefficient, weight, thickness, volume, superficial area, and ultimate compressive strength were measured, and their correlations were analyzed. The thickness, egg-shape coefficient, and ultimate compressive strength were normally distributed, and many parameters were strongly correlated. Moreover, finite element analysis was conducted to evaluate the compressive resistance of egg-like pressure shells made from different materials, including metal, ceramic, resin, and selenium-enriched eggshell materials. The performance ratio of the ceramic shells was 2.6 times higher than that of eggshells, and eggshells outperformed metal and resin shells by factors of 2.14 and 4.49, respectively. The eggshells had excellent compression resistance. These findings offer novel insights into the design and optimization of egg-like pressure shells. Full article

Selenium–polysaccharides possess antioxidant properties, making them promising materials for functional foods, pharmaceuticals, and clinical applications. This study examines the incorporation of selenium into polysaccharides via mycelial biosynthesis and its effects on structure and antioxidant activity. Polysaccharides obtained from Lentinula edodes-submerged cultures grown in Se-supplemented and non-supplemented media were analysed for Se content (RP-HPLC/FLD), structure (FT-IR, HPLC, and HPGPC-ELSD), and antioxidant activity (DPPH scavenging, reducing power, and Fe²⁺ chelation). Two low-molecular-weight Se–heteropolysaccharides (Se-FE-1.1 and Se-FE-1.2) containing ~80 and 125 µg/g Se were isolated, primarily composed of glucose, mannose, and galactose with β-glycosidic linkages. Se incorporation into polysaccharides selectively enhanced their antioxidant activity in the DPPH radical scavenging assay, with minimal effects observed in iron chelation and reducing power assays. Crude Se–polysaccharides displayed the highest antioxidant activity, suggesting an additional contribution from protein components. Our findings demonstrate that Se is effectively incorporated into polysaccharides, altering monosaccharide composition while preserving glycosidic linkages. The selective enhancement of radical scavenging suggests that selenium plays a specific role in antioxidant activity, primarily influencing radical scavenging mechanisms rather than interactions with metal ions. Further research is needed to clarify the mechanisms of selenium incorporation, the nature of its bonding within the polysaccharide molecule, and its impact on biological activity. Full article

Although total selenium content is still useful in many areas, knowledge of its speciation is gaining importance as its various chemical forms have different environmental effects, toxicities and biological utilization. Among several methods used for the isolation and enrichment of selenium species, solid-phase extraction and its alternative approaches are often applied due to their simplicity and high efficiency. This brief overview summarizes the progress made in using different nanostructure sorbents to separate and preconcentrate inorganic selenium species in environmental waters. Nanomaterials are finding increasing applications as they have a large specific surface area and high chemical stability. Functionalizing their surface by covalent or noncovalent interactions with other components, grafting or doping with heteroatoms can improve the separation and removal efficiency. Strategies based on combining selective chemical reactions and separation procedures are discussed. Full article

A method for the determination of trace selenium in water enriched by metal–organic−framework material (MIL−125−NH₂) and reversed−phase ultra−high−performance liquid chromatography−diode array detection (UPLC−DAD) was established. The MIL−125−NH₂ material, synthesized by the microwave method, was characterized by SEM, XRD, and FT−IR. The MIL−125−NH₂ material was added to the water sample to enrich the selenium, the enriched selenium was desorbed with dilute HCl, and then the derivative reaction with 0.1 mol·L⁻¹ 4−nitro−o−phenylenediamine was performed to produce piaselenole. After extraction with cyclohexane, the retention time and the spectrogram were qualitatively detected by a liquid chromatography−diode array detector, and the peak area was quantitatively detected. The pH, time, amount of material, extractant, and other conditions of derivation and enrichment were optimized in the experiment, and the methodology was verified under optimized conditions. The results showed that the linear correlation coefficient R² was 0.9998, the detection limit of 0.13 μg·L⁻¹ without enrichment was close to that of the ICP−MS method, the detection limit after 10−fold enrichment was 0.013 μg·L⁻¹, the RSD was 0.7~2.7%, and the recovery was 87.8~102.1%, in the range of 2~1000 μg·L⁻¹. Therefore, the method can be applied for the determination of trace selenium in tap water, river water, mountain spring water, packaged drinking water, and industrial sewage. Full article

This study investigates selenium (Se) biofortification in four strains of the medicinal mushroom Hericium erinaceus using Se-enriched substrates to assess Se uptake, distribution, and its impact on yield. Experimental substrates included lignocellulosic materials fortified with Se (0, 2, 6, and 18 µg/g) in the form of sodium selenite. Se accumulation varied by strain, with M9521 showing the highest bioaccumulation efficiency, particularly for an unknown Se compound, suggesting unique metabolic pathways. Other strains predominantly accumulated selenomethionine. The bioconcentration factor was highest at 6 µg/g Se, indicating optimal efficiency at this level. Moderate Se supplementation (2–6 µg/g) improved yield, though time to harvest was affected by Se levels in some strains. Substrate composition influenced Se uptake, with wheat bran yielding the highest Se content and soybean hulls maximizing biological efficiency. A strong correlation between C/N and Se content was observed. Se distribution was higher in outer basidiocarp layers, and light intensity during cultivation enhanced Se accumulation. Se uptake decreased with subsequent flushes at medium and high supplementation levels, while substrates maintained the same bioavailable Se. The results highlight the potential of Se-enriched Hericium erinaceus as a functional food source and the role of substrate and cultivation conditions in optimizing Se content. Full article

Climate changes cause various types of abiotic stress in plants, thus affecting plant growth and causing decline in yield. An urgent need exists to develop an environmentally friendly attitude based on principles of sustainable agriculture. Nanomaterials may improve plant growth and enhance crop productivity by handling the conditions considered stressful for plants in a sustainable and ecofriendly manner. Selenium (Se) has been put into the category of beneficial elements in plants. Se-enriched crops present a successful choice of dietary resource for Se-supplemented food and feed owing to their high bioavailability and accessibility. Researchers from distinct areas, including both nanoscience and plant science, should encourage emerging innovations that are linked with abiotic stress in crop production. The implementation of Se nanoparticles (SeNPs) is considered one of the predominating mechanisms by plants to ameliorate stressful conditions. Increasing evidence of earlier research revealed that SeNPs could enhance plant growth and development, nutrient bioavailability, soil fertility, and stress response while maintaining environmental safety. Meanwhile, some earlier studies reported that SeNPs might have a multilateral influence on plants dependent on diverse Se nanomaterial traits, doses, and plant species. More efforts are required to enhance the knowledge of how SeNPs impact crops exposed to different abiotic detrimental factors. In light of contemporary research challenges linked to SeNPs and the prolonged application of Se nanomaterials to plants, the aim of this review is elucidating the principal fruitful areas of SeNP exploration, comparisons with bulk Se, insights into mechanisms of abiotic stress alleviation in plants, existing research uncertainties, and practical challenges for SeNP applications under varying environments. Full article

Selenium (Se) is an essential micronutrient for the human body and is closely linked to health. Rice (Oryza sativa L.), as a major staple food globally, is the primary source of Se intake for humans. To better achieve Se biofortification in rice, it is crucial to understand the molecular mechanisms behind rice’s response to different Se concentrations. This study investigates the morphological and transcriptomic responses of rice seedlings to low (1 µM, LSe) and high (10 µM, HSe) Se concentrations compared to a control (CK). Morphological analyses revealed that LSe promoted growth, enhancing shoot and root length and biomass, whereas HSe treatment inhibited these parameters, indicating Se’s dual role in rice growth. Notably, the most significant promotion of rice growth was observed at the Se concentration of 1 µM. The organic Se content and antioxidant enzyme activities (SOD, POD and CAT) in rice seedlings also reached their maximum values simultaneously. Total RNA was extracted for transcriptome sequencing, and differential gene expression analysis was conducted using DESeq2. Transcriptomic sequencing highlighted distinct responses under LSe and HSe conditions. Gene ontology (GO) enrichment analysis revealed significant involvement in processes related to oxidoreductase activity and cellular structures. KEGG pathway analysis emphasized that Se treatments notably enhanced the glutathione metabolism pathway, which is crucial for antioxidant defense. Additionally, significant changes were observed in starch and sucrose metabolism and cysteine (Cys) and methionine (Met) metabolism pathways, showing upregulation under LSe treatment and downregulation under HSe. Six key genes were validated using qRT-PCR, confirming their differential expression under varied Se treatments. The Cys, Met and starch content assays as well as qRT-PCR data demonstrated that LSe promoted the synthesis and accumulation of Cys, Met and starch, supporting enhanced growth and antioxidant capacity. Conversely, HSe inhibited the synthesis and accumulation of Cys, Met and starch in rice seedlings, and these data were also consistent with the physiological phenotype. These findings provide insights into the molecular mechanisms by which rice seedlings adapt to varying Se levels, with implications for Se biofortification and stress management strategies in crops. Full article

Common beans are an essential food source worldwide, particularly in developing countries, and are grown in soils poor in selenium (Se), a mineral essential for human health. Adding Se to fertilizers is a promising technique; however, more studies are needed on the efficacy of this technique on common beans. This study aimed to evaluate the biofortification utilizing Se-enriched nitrogen fertilizers on common bean seeds’ agronomic, physiological, and nutritional characteristics. The pot experiment used a randomized block design with five treatments (urea, Se-enriched urea, ammonium sulfate, Se-enriched ammonium sulfate, and without N and Se), four genotypes (BRS Cometa, BRS Estilo, BRSMG Madrepérola and Pérola), and three replicates. The highest seed yield was 28.31 g pot⁻¹ with Pérola genotype fertilized Se-enriched ammonium sulfate. Photosynthetic rates ranged from 30.37 to 39.06 µmol m⁻² s⁻¹ for Pérola and BRSMG Madrepérola, both with Se-enriched ammonium sulfate. The highest seed Se concentration was 11.17 µg g⁻¹, with BRSMG Madrepérola fertilized with Se-enriched urea being 22.02%, 17.64%, and 22.47% higher than BRS Cometa, BRS Estilo, and Pérola, respectively. Se-enriched nitrogen fertilizers boost seed yield and alter physiological responses based on genotypes and Se-fertilizer interactions. Se-enriched fertilizers applied to soil can increase the Se concentration in common beans. Full article

Selenium-enriched vegetables are a safe way to combat selenium deficiency in humans. Here, a new microbial selenium-enriched bacterial fertilizer (named “HJ”) was prepared and studied by dipping, and then its application strategy was optimized and compared with other commercially available selenium fertilizers. The results showed that the application of HJ selenium fertilizer to peas by soaking (Se concentration 10 μg/mL) and foliar application (Se concentration 8 μg/mL) could effectively enhance their growth, selenium enrichment ability, stress tolerance and nutritional quality. In particular, the selenium content of peas in the HJ-treated group exhibited a significant increase of 69.86% in comparison with the control group. Moreover, HJ treated pea sprouts demonstrated enhanced antioxidant activity, as well as elevated levels of vitamin C and protein, amongst other observations. The findings of this study offer novel insights into the development of eco-friendly selenium fertilizers and provide guidance for optimal fertilizer application techniques. Full article

Selenium (Se) is an essential trace element for human health, and dietary Se intake is an effective supplement. Rich in nutrients and functional components with potential for Se enrichment, Tartary buckwheat (Fagopyrum tataricum (L.) Gaertn.) is a Se-biofortified cereal. To determine the optimal Se treatment concentration and fully understand its effects on Tartary buckwheat, sodium selenite (Na₂SeO₃) in different concentrations was sprayed onto leaves of Tartary buckwheat at the initial flowering stage. Agronomic and yield-related traits and Se enrichment were analyzed between CK and treatments. The results showed that Na₂SeO₃ concentrations of 3.0 and 6.0 mg/L significantly increased the contents of Se and starch in the grains, the 1000-grain weight, the number of grains per plant, and the yield. The 6.0 mg/L treatment had the best effect. Transcriptome and weighted gene co-expression network analyses showed that selenite promoted chlorophyll synthesis and photoelectron transport by upregulating chlorophyll synthase (CHLG) and protein CURVATURE THYLAKOID 1B (CURT1B) levels, improving photosynthesis, increasing sucrose synthesis and transport in leaves and starch synthesis and accumulation in grains, and promoting grain-filling and yield. These changes were regulated by genes related to photosynthesis, sucrose, and starch metabolism-related genes, including CAB3C, HPR3, SUS5, BAM9, SS3, SWEET1, and SWEET12. Selenite absorption in Tartary buckwheat was regulated by aquaporin genes NIP1-1 and PIP1-5. Selenite transport was regulated by the inorganic phosphate transporter gene PHT1-1, and organic Se transport was controlled by the proton-dependent oligopeptide transporters NPF3.1 and NPF4.6. Methionine gamma-lyase (MGL) was involved in selenocompound metabolism. This study identified the best spraying scheme for enhancing Se content in the grains. It also revealed the regulatory genes responding to selenite absorption, transport, and metabolism and the regulatory pathways promoting yield in Tartary buckwheat. These results provide technical guidance and theoretical support for producing high-yielding and Se-enriched Tartary buckwheat. Full article

Selenium (Se) biofortification is a promising agronomic strategy to enhance the dietary intake of this essential micronutrient while simultaneously adding value to agricultural by-products like Brassica oleracea L. var. italica leaves. This study evaluated the effects of foliar Se biofortification on a fresh market broccoli cultivar (‘Belstar’) using selenite and selenate (1 and 2 mM). Growth performance, biochemical properties, nutraceutical quality, and phytohormone profiles of broccoli leaves were analyzed, highlighting their potential as functional by-products. Multivariate analysis revealed that 2 mM selenite application was the most effective treatment, significantly improving several parameters. Selenium biofortification with 2 mM selenite increased essential nutrient content, including Se, Ca, S, Fe, Mn, Mg, and Mo. It also enhanced the soluble protein content (+2.2-fold), phenolic compounds (+1.5-fold), and total antioxidant capacity (+1.4-fold) compared to control plants. In this sense, the nutraceutical quality of broccoli leaves was markedly improved, supporting their use as a source of bioactive ingredients. Additionally, to assess practical applications, water-extracted Se-enriched broccoli leaves demonstrated antifungal activity against the plant pathogen Fusarium solani, attributed to Se-induced alterations in phytohormone profiles. These findings suggest that Se-biofortified broccoli leaves can serve as a sustainable source of essential nutrients and bioactive compounds for the food industry. Furthermore, their antifungal properties position them as potential eco-friendly biopesticides to combat plant pathogenic fungi, thereby promoting sustainable agriculture. Full article