Μg Se Research Articles

Burden of selenium deficiency and cost-effectiveness of selenium agronomic biofortification of staple cereals in Ethiopia.

Selenium (Se) deficiency among populations in Ethiopia is consistent with low concentrations of Se in soil and crops that could be addressed partly by Se-enriched fertilisers. This study examines the disease burden of Se deficiency in Ethiopia and evaluates the cost-effectiveness of Se agronomic biofortification. A disability-adjusted life years (DALY) framework was used, considering goiter, anaemia, and cognitive dysfunction among children and women. The potential efficiency of Se agronomic biofortification was calculated from baseline crop composition and response to Se fertilisers based on an application of 10 g/ha Se fertiliser under optimistic and pessimistic scenarios. The calculated cost per DALY was compared against gross domestic product (GDP; below 1-3 times national GDP) to consider as a cost-effective intervention. The existing national food basket supplies a total of 28·2 µg of Se for adults and 11·3 µg of Se for children, where the risk of inadequate dietary Se reaches 99·1 %-100 %. Cereals account for 61 % of the dietary Se supply. Human Se deficiency contributes to 0·164 million DALYs among children and women. Hence, 52 %, 43 %, and 5 % of the DALYs lost are attributed to anaemia, goiter, and cognitive dysfunction, respectively. Application of Se fertilisers to soils could avert an estimated 21·2-67·1 %, 26·6-67·5 % and 19·9-66·1 % of DALY via maize, teff and wheat at a cost of US$129·6-226·0, US$149·6-209·1 and US$99·3-181·6, respectively. Soil Se fertilisation of cereals could therefore be a cost-effective strategy to help alleviate Se deficiency in Ethiopia, with precedents in Finland.

The effects of selenium administration on mean platelet volume, neutrophil-to-lymphocyte ratio, and red cell distribution width in critically ill older adults: A double-blinded randomized clinical trial

BackgroundLow serum Selenium (Se) levels in critical patients have been associated with poor clinical outcomes and higher mortality rates. The purpose of this study was to investigate the effect of Se administration on mean platelet volume (MPV), neutrophil-to-lymphocyte ratio (N/L), and red cell distribution width (RDW) in older adults admitted to the intensive care unit (ICU). MethodThis study was a double-blinded randomized clinical trial. Critically ill patients were randomly divided into two groups of Se and placebo. The Se group (N=30) initially received 3000 mg of Se at once within 3 hours, followed by a dose of 1500 mg daily for 10 days as a one-hour infusion. The control group (N=30) received normal saline for 10 days. A venous blood sample was collected on the first and 10th day. Statistical analysis was performed using SPSS.26 statistical software. To analyze quantitative data in two groups, based on the estimated normality, an independent t-test was used. P value less than 0.05 was considered statistically significant. ResultsOn day 10, the MPV value in the Se group was significantly lower compared to the placebo group (9.32 ± 1.78 and 10.43 ± 2.06, respectively, p = 0.03). Within the Se group, contrary to the controls, the MPV value decreased significantly from day 1 to day 10 (p<0.001). Further, the RDW value in the Se group was significantly lower compared to the placebo group (13.77 ± 1.57 and 15.32 ± 2.42, respectively, p = 0.005). The N/L ratio remained similar between the two groups before and after the intervention. ConclusionOur findings suggest that Se can affect the MPV and RDW parameters in older adults hospitalized in the ICU. However, further studies with a larger population are necessary to support these findings. Clinical Relevancy StatementThe effects of selenium administration on hematological parameters in older adults admitted to the ICU are not well-established. There is limited direct evidence linking serum selenium levels to erythrocyte and hemoglobin stability in humans. The current clinical trial promotes the current literature and shows that selenium holds potential in management of the older ICU patients.

High levels of the health-relevant antioxidant selenoneine identified in the edible mushroom Boletus edulis

BackgroundSelenoneine, the selenium analogue of the sulfur antioxidant ergothioneine, has been ascribed a multitude of beneficial health effects. Natural nutritional sources for this selenium species are, hence, of high interest. So far marine fish is the only significant selenoneine source consumed by larger parts of the population worldwide. MethodsAs selenoneine and ergothioneine share their biosynthetic pathways and transport mechanisms and the popular edible porcini mushroom Boletus edulis is rich in ergothioneine and selenium, we conducted a preliminary study investigating a composite sample of two specimens of B. edulis for their selenoneine content by HPLC coupled to elemental and molecular mass spectrometry after aqueous extraction. ResultsSelenium speciation analysis by HPLC-ICPMS revealed that ca. 860 µg Se kg−1 wet mass (81 % of the total Se) co-eluted with a selenoneine standard and a minor selenium species with Se-methylselenoneine. The presence of selenoneine was rigorously proven by HPLC-ESI-Orbitrap MS. The selenoneine content of the investigated specimens of B. edulis was higher than that of commonly consumed muscle of marine fish species, like tuna or mackerel. ConclusionThis is the first report of a terrestrial food source containing significant selenoneine levels. Our results suggest that B. edulis might represent a complementary natural supply with this health-relevant selenium species for humans.

Effects of Selenate Application on Growth, Nutrient Bioaccumulation, and Bioactive Compounds in Broccoli (Brassica oleracea var. italica L.)

The biofortification of edible crops with selenium (Se) is a common and effective strategy to address inadequate Se intake, which is suffered by millions of people worldwide. However, there is little information regarding the effects of this practice on crops belonging to the important Brassica family. To evaluate the efficacy of foliar Se application on broccoli, four treatments with varying Se concentrations were tested: 0%, 0.05%, 0.10%, and 0.15% (w/v), applied as sodium selenate during the early flowering stage. Although no overall effects on growth and biomass parameters were observed, the results indicate that the lowest Se dose (0.05-Se) was sufficient to notably increase Se concentration in the florets, even after boiling. Based on the increase to 14.2 mg Se kg−1 of dry matter in this broccoli fraction, it was estimated that consuming a 100-gram portion of boiled florets biofortified with 0.05% Se would provide approximately 140 µg of Se, which could be sufficient to potentially improve human selenium status, as previously documented. Moreover, the results obtained underscore how the application of this small dose was also adequate to reduce phytate concentration in the florets and to increase antioxidant and polyphenol concentrations, thereby improving the concentration and bioavailability of other essential nutrients, including Ca, Mg, Fe, and Zn, along with improving its quality as an antioxidant food.

Dynamics of selenium-mercury interaction under mercury stress in high and low selenium rice genotypes

Recent studies have demonstrated that selenium (Se) reduces the accumulation of heavy metals in rice tissues. However, the interaction between Se and mercury (Hg) in rice genotypes with high Se content remains to be further investigated. In this study, we used high Se genotypes Z2057B and Z5097B and low Se genotype Yuenong to explore the dynamics of Se and Hg in various tissues. The results showed that high Se genotypes, coupled with low concentrations of exogenously applied Se, significantly reduced the uptake of Hg in rice plants. The findings indicated the following order of Hg accumulation: Roots> third leaf > second leaf > first leaf > stem > grains. Observations revealed that both high Se genotypes and Se supplementation significantly restricted the majority of Hg concentration in roots and minimized its translocation to the aerial parts of the rice plant. In high Se genotypes subjected to mercury stress, MDA accumulation was significantly reduced, and SOD antioxidant activity was enhanced in stem and leaves at jointing, booting, heading, and maturity stages as compared to low Se genotypes. The application of 1.0 mg of Se per kg soil significantly improved the agronomic and physiological characteristics, reduced the Hg contents in aerial parts, and increased the Se contents in polished rice grains. Hence, the results lead to the conclusion that (i) cultivating high Se rice genotypes is a viable approach to decrease the Hg accumulation in rice grains and serves as a crucial strategy to fulfill daily Se requirements, particularly for populations suffering from Se deficiency (ii) supplementing ordinary rice with 1–3 mg kg−1 of Se can effectively reduce Hg accumulation and improve the quality of the grains.

Selenium inorganic sources applied to soil: Effects on gas exchange and anatomical changes of radishes

Selenium (Se), in low doses, provides several beneficial effects, such as plant resistance to various abiotic stresses (e.g. drought stress and low/high temperatures). However, Se excess causes toxicity, with harmful impacts such as a decline in yield. Here, we studied the effects of fertilization with different Se sources and doses applied via soil on Se accumulation, toxicity, as well as on gas exchange, and anatomy of leaves and roots of radish plants. A randomized experimental design was adopted with three replications in a 2 × 3 + 1 factorial arrangement: two Se sources (sodium selenate – Na2SeO4 and sodium selenite – Na2SeO3·5H2O), three Se doses applied on soil (0.6, 1.2, and 1.8 mg dm−3), and one control treatment (without Se application). Each experimental unit consisted of one pot containing six radish plants. Selenate at 1.8 mg Se dm−3 increased the Se accumulation and radish dry matter. Selenite generally caused significant changes in the anatomical part, mainly in the conductive tissues of the leaves. In leaves with selenite fertilization, it was estimated that the maximum Se accumulation would be 5.9 µg plant−1 with a rate of 2.0 mg Se dm−3. However, it was impossible to estimate the maximum Se accumulation with selenate fertilization because as the dose increased, there were also increases in accumulation, thus presenting a linear regression. The maximum Se accumulation in radishes would be 10.7 µg Se plant −1 with 1.2 mg Se dm−3 by selenite and 45.8 µg Se plant−1 with 5.0 mg Se dm−3 by selenate. Although the highest dry mass production occurred with the 1.8 mg Se dm−3 through selenite, it is recommended to use smaller doses to provide adequate Se consumption selenate. The gas exchange and the anatomy of the plants changed due to Se fertilization through selenate and selenite.

Combined Supplementation of Two Selenium Forms (Organic and Inorganic) and Iodine in Dairy Cows' Diet to Obtain Enriched Milk, Cheese, and Yogurt.

This study evaluated the effects of dietary supplementation in dairy cows with two Se forms (organic and inorganic) and I at the maximum levels permitted in the European Union, with the aim to obtain naturally enriched milk and derived products. A total of 20 Holstein Friesian cows in lactation were fed 2 diets for 64 days: a control diet with a supply of 0.57 mg of inorganic Se and 0.57 mg of I per kg of ration in dry matter (DM), and an experimental diet (SeI) with a supply of 0.34 mg of inorganic Se, 0.23 mg of organic Se, and 5.68 mg of I per kg of ration in DM. The SeI diet did not modify the performance or, in general, the metabolic profile of cows. Se and I levels in milk were affected by diet type and time of measurement (p < 0.01). Thus, a marked increase of both microminerals was evident between the beginning and the end of the test, when the SeI diet was administered. For Se, this increase ranged from 1.95 to 3.29 μg/100 g of milk; and for I, from 19.69 to 110.06 μg/100 g of milk. The SeI diet increased (p < 0.01) the Se and I content in the cheese, reaching levels of 16.4 μg/100 g for Se and 269.7 μg/100 g for I. An increase in I was observed in yogurt from the SeI diet (p < 0.001). The supplementation of two forms of Se and I in the cows' ration, at the levels evaluated, produced milk and dairy products enriched in these microelements without altering their quality parameters. However, a responsible intake of these products is necessary to avoid risks of deficiencies or excesses that could negatively affect the health of consumers.

Plant-soil relations of selenium, molybdenum and vanadium in the Richmond District of Central Queensland, Australia

Abstract Background and aims The Richmond District of Queensland (Australia) hosts seleniferous soils and is the habitat of selenium (Se) hyperaccumulator plants. These soils are also naturally enriched in vanadium (V) and molybdenum (Mo). This study aimed to survey soils and plants of the Richmond area with a focus on the Se hyperaccumulator Neptunia amplexicaulis. Methods Field collection of plant specimens and soils from the seleniferous outcrops of the Richmond District (including the Julia Creek area) was undertaken and the samples were analyzed for Se, V, Mo and other elements. Results The results show that three modes of Se accumulation can be observed with most plant species having from ~10 μg Se g−1 up to 70 μg Se g−1 in shoots, some having between 75 and 250 μg Se g−1 in shoots while both N. amplexicaulis and Acacia tephrina contained 450–700 μg Se g−1 in their shoots. There was high Se accumulation in the phyllode tips of A. tephrina. Previously unrecorded populations of N. amplexicaulis were discovered near Julia Creek. Selenium concentrations in soil are lower than historically reported from similar localities (up to 23.2 mg Se kg−1). Molybdenum concentrations between 213 and 329 μg Mo g−1 occurred in the two Se hyperaccumulators N. amplexicaulis and A. tephrina, whilst Salsola australis had the highest accumulation of V (31–66 μg V g−1). Conclusions The results suggest that the Toolebuc Formation is the source of Se in the region, but temporal variability alters how much Se is bioavailable to plants. The presence of high Mo in plant tissues is linked to Se hyperaccumulation, and V accumulation appears to have little impact on plant ecology.

Distribution of selenium: A case study of the Drava, Danube and associated aquatic biotopes

This paper presents the results of the research on the overall distribution of selenium (Se) in various aquatic compartments (water, sediment, plankton and macrophytes) at six selected sites of the Croatian part of the Drava and Danube rivers, the connected floodplain lake and the melioration channel system carried out in two sampling periods (flooding in June and the drought period in September). In addition, the physicochemical water properties, plankton composition and biomass were analysed. Our study revealed low mean Se contents in sediments and water, indicating Se deficiency in the studied freshwater systems. The physicochemical environment, including Se distribution, was primarily influenced by hydrology rather than site-specific biogeochemical and morphological characteristics. The flooding period was characterised by higher Se content in water and higher transparency, nitrate and total nitrogen concentrations than drought conditions. At the river sites, sediment Se content was the highest during the flood period, while at all other sites, higher concentrations were found during the drought, reaching the maximum in the lake. Although Se concentrations were below the threshold for aquatic ecotoxicity, they increased in the following order: water (0.021–0.187 μg Se L−1) < sediments (0.005–0.352 mg Se kg−1) < macrophytes (0.010–0.413 mg Se kg−1) < plankton (0.044–0.518 mg Se kg−1) indicating its possible biomagnification at the bottom of the food chain. Species known for high Se accumulation potential dominated the biomass of the main plankton groups and the composition of the macrophyte community, which may provide a more sensitive and accurate steady-state compartment monitor for Se assessment in freshwater biotopes.

Selenized lactic acid bacteria microencapsulated by spray drying: A promising strategy for beef cattle feed supplementation.

This study aimed to assess the technical feasibility of incorporating selenized Lactobacillus spp. microencapsulated via spray drying into cattle feed. Gum Arabic and maltodextrin were used as encapsulating agents. The encapsulation process was carried out with a drying air flow rate of 1.75m3/min, inlet air temperature of 90°C, and outlet air temperature of 75°C. The viability of the encapsulated microorganisms and the technological characteristics of the obtained microparticles were evaluated. Microorganisms were incorporated into beef cattle feed to supplement their diet with up to 0.3mg of Se per kilogram of feed. The encapsulated particles, consisting of a 50/50 ratio of gum Arabic/maltodextrin at a 1:20 proportion of selenized biomass to encapsulant mixture, exhibited superior technical viability for application in beef cattle feed. Supplemented feeds displayed suitable moisture, water activity, and hygroscopicity values, ensuring the preservation of viable microorganisms for up to 5months of storage, with an approximate count of 4.5logCFU/g. Therefore, supplementing beef cattle feed with selenized and microencapsulated lactic acid bacteria represents a viable technological alternative, contributing to increased animal protein productivity through proper nutrition.

Selenium biofortification of microgreens: Influence on phytochemicals, pigments and nutrients

Kale (Brassica oleracea L. var. sabellica L.), kohlrabi (Brassica oleracea L. var. gongylodes L.) and wheat (Triticum aestivum L. cv. Bancal) microgreens were cultivated in presence of selenium 20 μmol L−1 as sodium selenite and sodium selenate mixture. The influence of this biofortification process was evaluated in terms of biomass production, total Se, macro- and micronutrients concentration, polyphenols, antioxidant activity, chlorophylls and carotenoids levels and total soluble proteins content. The results obtained have shown a significant concentration of total Se in the biofortified microgreens of kale (133 μg Se·g−1 DW) and kohlrabi (127 μg Se·g−1 DW) higher than that obtained for wheat (28 μg Se·g−1 DW). The Se uptake in all the species did not produce oxidative damage to the plants reflected in the bioactive compounds, antioxidant capacity or pigments concentration. These Se-enriched microgreens may contribute to the recommended intake of this nutrient in human diet as to overcome Se-deficiency.

Biofortification of kale microgreens with selenate-selenium using two delivery methods: Selenium-rich soilless medium and foliar application

Selenium (Se) is essential for human health as it is involved in various fundamental biological functions. This study aimed to assess the effects of Se enrichment in kale microgreens through biofortification in a soilless cultivation system. Two Se (as sodium selenate) application methods were assessed, including supplementation into the nutrient solution or as a foliar spray at four concentrations: 0, 10, 20 and 40 µM Se in a completely randomized design considering triplicates. For this purpose, minerals, nitrate and ammonium content, as well as fresh yield and dry matter of kale microgreens, were recorded after a 14-day growing period in an environmentally controlled vertical farm. Results showed that kale microgreens successfully accumulated up to 893.3 and 24 µg Se/ kg dry matter under the nutrient solution and foliar treatments, respectively, while yield remained unaffected. Selenium (Se) enrichment of the nutrient solution at 20 µM Se concentration resulted in the optimum treatment for fresh consumption purposes and supplying this element in human diets in the future, providing adequate dietary Se in less than five grams of the fresh kale microgreens.

Phase partitioning of mercury, arsenic, selenium, and cadmium in Chlamydomonas reinhardtii and Arthrospira maxima microcosms

As the global human population increases, demand for protein will surpass our current production ability without an increase in land use or intensification. Microalgae cultivation offers a high yield of protein, and utilization of wastewater from municipal or agricultural sources in place of freshwater for microalgae aquaculture may increase the sustainability of this practice. However, wastewater from municipal and agricultural sources may contain contaminants, such as mercury (Hg), cadmium (Cd), selenium (Se), and arsenic (As). Association of these elements with algal biomass may present an exposure risk to product consumers, while volatilization may present an exposure hazard to industry workers. Thus, the partitioning of these elements should be evaluated before wastewater can be confidently used in an aquaculture setting. This study explored the potential for exposure associated with Arthrospira maxima and Chlamydomonas reinhardtii aquaculture in medium contaminated with 0.33 μg Hg L−1, 60 μg As L−1, 554 μg Se L−1, and 30 μg Cd L−1. Gaseous effluent from microalgae aquaculture was analyzed for Hg, As, Se, and Cd to quantify volatilization. A mass balance approach was used to describe the partitioning of elements between the biomass, medium, and gas phases at the end of exponential growth. Contaminants were recovered predominantly in medium and biomass, regardless of microalgae strain. In the case of Hg, 48 ± 2% was associated with A. maxima biomass and 55 ± 8% with C. reinhardtii when Hg was present as the only contaminant, but this increased to 85 ± 11% in C. reinhardtii biomass when As, Se, and Cd were also present. A small and highly variable abiotic volatilization of Hg was observed in the gas phase of both A. maxima and C. reinhardtii cultures. Evidence presented herein suggests that utilizing wastewater containing Hg, Cd, Se, and As for microalgae cultivation may present health hazards to consumers.

Effect of the Addition of Selenium and some Competing Anions on Selenium Concentration in Maize Growing in some Soils in Central Iraq

The effect of selenium and some competing anions to the soil on selenium concentration in maize growing in AL-Herria (clay )soil and Khan al-Nass (Sandy Loam )soil was studied. four levels ( 0, 20, 40 and 60 )gm Se ha-1 and three levels of Sulfur and (0, 45, 90 )Kg S ha-1 and phosphate in doses of (0, 90, 180) Kg P ha-1 were added to the soil. Maize plant content of selenium increased significantly, with increasing soil applications of selenium in both soils. While the plant content of selenium was decreased from (79.75 to 76.32 and 72.09 μg Se gm-1)and from (47.08 to 44.04 and 41.2 μg Se gm-1)with addition of as and 90 kg S ha -1 to Al-Herria and khan al-Nass soils respectively. Plant selenium content was also decreased from 79.75 to 76.32 and 72.09 and from 46.38 to 44.28 and 41.64 μg Se gm-1 with soil application of 90 and 180 kgP ha-1 to Al-Herria and khan al-Nass soils respectively. Increasing addition of and phosphorus censed decreasing of selenium content of corn plant in both soils.

Bioaccumulation of selenium in halotolerant microalga Dunaliella salina and its impact on photosynthesis, reactive oxygen species, antioxidative enzymes, and neutral lipids

Selenium (Se) is an essential element for living systems, however, toxic at higher levels. In the present study, Dunaliella salina cells were exposed to different Se concentrations for their growth (EC50 195 mg L−1) as well as Se accumulation. The cells exposed to 50 mg L−1 Se showed photoautotrophic growth parallel to control and accumulated 65 μg Se g−1 DW. A decrease in photosynthetic quantum yield, chlorophyll content, and the increase in intracellular reactive oxygen species, proline content, and lipid peroxidation accompanied by higher neutral lipid accumulation, were recorded at higher Se level. The enzymes superoxide dismutase and catalase played a pivotal role in antioxidative defense. Heterogeneity in accumulated carotenoids at varying concentrations of selenium was prevalent. The cells exposed to 200 mg L−1 Se resulted in the disorganization of organelles. Thus, the Se enriched biomass obtained at 50 mg L−1 may be explored for bio-fortification of food and feed.

How to Efficiently Produce the Selenium-Enriched Cucumber Fruit with High Yield and Qualities via Hydroponic Cultivation? The Balance between Selenium Supply and CO2 Fertilization

Hydroponic-producing selenium (Se)-biofortified vegetables in a greenhouse is a convenient and effective way to provide Se-enriched food and overcome hidden hunger. CO2 fertilization is commonly implemented to increase vegetable yield in greenhouse production. However, this application accompanies decreased mineral concentrations in the edible parts. Here we investigated the effects of [CO2] and Se supply on the growth, gas exchange, and cucumber fruit quality. A hydroponic experiment with two CO2 concentrations ([CO2]) (C1: 410, and C2: 1200 μmol mol−1) and four Se supply levels (Se0: 0, Se1: 0.125, Se2: 0.250, and Se3: 0.500 mg Se L−1) was carried out. A low level of Se supply (Se1: 0.125 mg Se L−1) protected the photosynthetic pigments and stimulated the stomatal opening, especially under [CO2] fertilization. It leads to a higher net photosynthesis rate (Pn) and transpiration rate (Tr) than other Se treatments. The most significant changes in dry weight, fruit yield, and soluble sugar concentration were also obtained in Se1 under CO2 fertilization due to the enhanced CO2 fixation. Meanwhile, the Se concentration in fruit was 0.63 mg kg−1 FW in C2Se1, with the highest Se accumulation and use efficiency. According to the recommended dietary allowance of 55 μg Se day−1 for adults, an intake of 87 g of cucumber grown in C2Se1 is sufficient. Because of the improved Tr and better root structure in Se1, the uptake of mineral nutrients through mass flow and interception was well maintained under CO2 fertilization. So, the concentrations of N, P, K, Ca, and Mn in cucumber fruits were not significantly decreased by elevated [CO2] in Se1. However, the concentrations of soluble proteins, S, Mg, Fe, and Zn in cucumber fruits in C2Se1 were lower than those in C1Se1, which was mainly attributed to the dilution effects under CO2 fertilization. Therefore, a selenite supply of 0.125 mg Se L−1 was found to be the optimal dosage for producing Se-enriched cucumber fruits with high yield and better qualities under CO2 fertilization (1200 μmol mol−1).

Natural Sources of Selenium as Functional Food Products for Chemoprevention.

Cancer is one of the leading causes of death worldwide, the incidence of which is increasing annually. Interest has recently grown in the anti-cancer effect of functional foods rich in selenium (Se). Although clinical studies are inconclusive and anti-cancer mechanisms of Se are not fully understood, daily doses of 100-200 µg of Se may inhibit genetic damage and the development of cancer in humans. The anti-cancer effects of this trace element are associated with high doses of Se supplements. The beneficial anti-cancer properties of Se and the difficulty in meeting the daily requirements for this micronutrient in some populations make it worth considering the use of functional foods enriched in Se. This review evaluated studies on the anti-cancer activity of the most used functional products rich in Se on the European market.

Efficacy of feeding hydroxy-selenomethionine on plasma and milk selenium in mid-lactation dairy cows

In this study, we aimed to determine the amount of Se transferred to milk and blood of mid- to late-lactation dairy cows when supplemental Se from hydroxy-selenomethionine (OH-SeMet) was fed compared with an unsupplemented group and a group supplemented with a seleno-yeast (SY). Twenty-four lactating Holstein cows (178 ± 43 d in milk) were used in a complete randomized block design for 91 d (7-d covariate period and 84-d treatment period). Treatments were (1) basal diet with an analyzed Se background of 0.2 mg of Se per kg as-fed (control); (2) basal diet + 0.3 mg of Se/kg as-fed from SY (SY-0.3); (3) basal diet + 0.1 mg of Se/kg as-fed from OH-SeMet (OH-SeMet-0.1); and (4) basal diet + 0.3 mg of Se/kg as-fed from OH-SeMet (OH-SeMet-0.3). During the trial, plasma and milk were analyzed for total Se, and plasma was analyzed for glutathione peroxidase activity. The mean plasma and milk Se concentrations exhibited the same relationship, where OH-SeMet-0.3 resulted in the highest values (142 µg/L of plasma and 104 µg/kg of milk), followed by SY-0.3 (134 µg/L and 85 µg/kg), OH-SeMet-0.1 (122 µg/L and 67 µg/kg), and the control group had the lowest values (120 µg/L and 50 µg/kg). The increment of Se in milk induced by OH-SeMet-0.3 (+54 µg/kg) was 54% higher than that induced by SY-0.3 (+35 µg/kg). Additionally, dietary supplementation of 0.2 mg/kg Se from OH-SeMet in the total mixed ration was estimated to be similar to 0.3 mg/kg Se from SY in the total mixed ration when considering the level of Se in the milk. There was no difference in plasma glutathione peroxidase activity between groups; however, OH-SeMet-0.3 significantly decreased somatic cell count. The results confirmed that supplementation with organic Se increases milk and plasma Se concentrations. Moreover, when administered at the same level of supplementation, OH-SeMet was shown to be more efficient than SY in improving milk quality by increasing Se content and decreasing milk somatic cell count.

Effects of selenium supplementation on concurrent chemoradiotherapy in patients with cervical cancer: A randomized, double-blind, placebo-parallel controlled phase II clinical trial.

Selenium (Se) is an essential trace element and may affect cervical cancer occurrence and progression. The association between selenium supplementation and acute toxic reactions and clinical outcomes in patients with locally advanced cervical cancer treated with concurrent chemoradiotherapy remains unclear. The aim of this study was to determine the safety profile of add-on Se yeast and assess the potential of Se to ameliorate the hematologic toxicity of concurrent chemoradiotherapy in patients with cervical cancer. Patients with Federation International of Gynecology and Obstetrics (FIGO) stage IIB cervical cancer who met all inclusion criteria were randomly assigned to either the experimental group or the control group. The experimental group received Se yeast tablets (100 μg Se, twice daily), while the control group received placebos (twice daily) for 5 weeks in total. All patients in both groups received standard treatment, including pelvic external irradiation, concurrent five cycles of chemotherapy, and brachytherapy. Measures included the incidence of myelosuppression, impairment of liver and kidney function, objective response rate (ORR), and blood Se concentrations before, during and after the treatment of the two groups. A total of 104 eligible patients were enrolled in the experimental group (n = 50) or the control group (n = 54). The ORR in the experimental group and control group were 96 and 94%, respectively (p = 0.47). The baseline levels of blood Se before treatment in the experimental and control groups were similar (58.34 ± 17.63 μg/L and 60.21 ± 18.42 μg/L, p = 0.60), but the concentrations became significantly different after course completion between the two groups (76.16 ± 24.47 μg/L and 57.48 ± 14.92 μg/L, respectively, p < 0.01). Se dramatically decreased the incidence of grade 3 myelosuppression (48% vs. 63%, p = 0.034) compared to the control group. In the subgroup of patients with moderately well-differentiated cervical cancer, the incidence of thrombocytopenia induced by concurrent chemoradiotherapy was lower in the experimental group than in the control group (53.8% vs. 78.9%, p < 0.01). However, no difference was observed in liver and kidney injuries between the two groups. Supplementation with Se effectively increased blood Se levels in Se-inadequate cervical cancer patients. As an add-on to standard treatment, Se-yeast significantly decreased the hematologic toxicity of concurrent chemoradiotherapy.

Enrichment of Culinary-Medicinal Oyster Mushroom, Pleurotus ostreatus (Agaricomycetes), Cultivated on the Straw Substrate with Zinc and Selenium.

Pleurotus ostreatus was cultivated on a commercially available wheat straw substrate enriched with Zn and Se. Various amounts of Zn (10, 50, and 100 mg) and Se (1, 5, and 10 mg) in suitable forms ((CH3COO)2Zn·2H2O, Zn(NO3)2·6H2O, and Na2SeO3·5H2O, respectively) were dissolved in 50 ml of deionized water and homogenously nebulized into the substrate block of 2.4 kg weight. The increase in the Zn content in fruiting bodies cultivated on the enriched substrate was relatively low compared with fruiting bodies cultivated on the substrate with no addition at the first flush. The application of different Zn compounds (acetate vs. nitrate) gave similar results. However, the addition of 1 mg of Se into the cultivation substrate block increased the content of Se in fruiting bodies to about 3-6 mg/kg dry matter. This content was one order of magnitude higher compared with the Se content in fruiting bodies harvested from the substrate with no Se addition (< 0.12-0.58 mg/kg dry matter). In the case of the addition of 5 mg of Se, there was a further significant increase in the content of this element to about 40-60 mg/kg dry matter.