Effect of selenium, sonication, and combination of selenium and sonication treatments on potassium bromate, alloxan, and titanium dioxide in bread

Improvers such as potassium bromate, titanium dioxide, and bleaching agents are used in breadmaking despite existing bans. This research aimed to detect potassium bromate, alloxan (a by-product of bleaching agents), and titanium dioxide in bread samples from local automated and traditional bakeries. Bread samples prepared from local durum wheat flour underwent treatments (sonication, selenium, and selenium with sonication). X-ray Fluorescence (XRF) did not detect titanium dioxide, while potassium bromide (a reduced form of potassium bromate) was detected in all samples. UV-visible spectroscopy detected alloxan in 37.5 % of bakeries. Among all treatments, selenium and sonication effectively reduced potassium bromide, alloxan, and titanium dioxide concentrations in spiked (10,000 μg/g) bread samples. Dynamic Light Scattering (DLS) showed particle sizes over 100 nm in all treated samples, and Scanning Electron Microscopy (SEM) revealed the surface morphology structure of rough, flaky surfaces with compact particles for all treated prepared, and spiked samples, indicating no nanoparticle formation.

Impact of chickpea biofortification on the bioaccessibility of micronutrients and their relationship to obesity-linked biological activities

Micronutrient deficiencies are a critical factor in the development of obesity. This work aimed to determine the Se and Zn bioaccessibility on biofortified chickpea flour and evaluate their impact on the antioxidant and anti-inflammatory activities. The greatest increase (235 %) in isoflavones was observed in the ZnSO4-treatment compared to the control. Malonylated-formononetin-glucoside was the major isoflavone (43 %-50 %) found in the treatments. Na2SeO3-treated seeds showed the highest Se accumulation, while the greatest Zn accumulation was found in ZnSO4-treated seeds. Se bioaccesibility followed the order: Germinated Control>ZnSO4 > ZnSeO3 > ZnSO₄ + Na2SeO3 > Na2SeO3, while in the seeds biofortified with Zn salts showed the order: Germinated Control>ZnSeO3 > ZnSO₄ + Na2SeO3 > Na2SeO3 > ZnSO4. All treatments showed antioxidant activity. Na2SeO3-treatment (15.625 μg/mL) showed a significant reduction of 52 % in NO production compared to the Germinated Control. These findings demonstrated the biological value of food biofortification in providing minerals in the diet to combat the oxidative stress characteristic of obesity.

Metabolism and Anticancer Mechanisms of Selocompounds: Comprehensive Review

Selenium (Se) is an essential micronutrient with several functions in cellular and molecular anticancer processes. There is evidence that Se depending on its chemical form and the dosage use could act as a modulator in some anticancer mechanisms. However, the metabolism of organic and inorganic forms of dietary selenium converges on the main pathways. Different selenocompounds have been reported to have crucial roles as chemopreventive agents, such as antioxidant activity, activation of apoptotic pathways, selective cytotoxicity, antiangiogenic effect, and cell cycle modulation. Nowadays, great interest has arisen to find therapies that could enhance the antitumor effects of different Se sources. Herein, different studies are reported related to the effects of combinatorial therapies, where Se is used in combination with proteins, polysaccharides, chemotherapeutic agents or as nanoparticles. Another important factor is the presence of single nucleotide polymorphisms in genes related to Se metabolism or selenoprotein synthesis which could prevent cancer. These studies and mechanisms show promising results in cancer therapies. This review aims to compile studies that have demonstrated the anticancer effects of Se at molecular levels and its potential to be used as chemopreventive and in cancer treatment.

Comparison of Regular and Selenium-Enriched Tortillas Produced from Sprouted Corn Kernels

Corn kernels were soaked with different selenium (Se) solutions (0, 12 or 24 mg Na₂SeO₃/L), sprouted for different times and then lime-cooked for the pilot plant production of tortillas. The dough and tortillas were quantified in terms of total Se, starch and protein content. Also, in vitro digestibility, texture, color, and sensory properties were evaluated. Results indicated that lime-cooking times were significantly reduced from 39.15 to 14.34, 8.42 and 2.80 min when whole corn was compared with kernels germinated for 1, 2 or 3 days. The Se content of regular tortillas (0.08 µg/g dw) increased about eight-fold in tortillas (0.651-0.625 µg/g dw) produced of corn germinated for two day and treated with 24 mg of Na₂SeO₃/L. The highest α-amylase activity and lower starch viscosity values were observed in 3-day germinated supplemented with the highest Se. Se-enriched tortillas produced from 2-day sprouted kernels treated with 12 mg Na₂SeO₃ showed the highest levels of general acceptability, texture and flavor.

Effect of selenium biofortification on bioactive compounds and antioxidant activity in germinated black soybean

Biofortification using inorganic selenium has become an effective strategy to enhance selenium content in crops. In the present study, the effects of selenium biofortification on the chemical composition and antioxidant capacity of black soybean (BS) during germination were studied. The contents of selenium, total sugar, vitamin C, γ-aminobutyric acid, total polyphenols, and total flavonoids in selenium biofortified germinated black soybeans (GBS-Se) significantly increased compared to germinated black soybeans (GBS). However, the contents of soluble protein, fat, and reducing sugar were decreased, while fatty acid composition was not significantly different between GBS and BS. HPLC analysis showed that 12 phenolic acids of all samples, which mainly existed in free forms. Their contents increased at low concentration of selenium and decreased along with the rise of selenium concentrations. The antioxidant activity of GBS-Se as analyzed by Pearson correlation analysis positively correlated with the accumulation of phenolic substances. Principal component analysis (PCA) showed that GBS and GBS-Se were significantly different from BS. Moreover, the physicochemical indexes of GBS showed regularly changes with increasing selenium content, and those of GBS-Se50 and GBS-Se75 were significantly different from GBS. The results provide a systematic evaluation on the effect of selenium fortification on the germination of seeds and useful information for the development of Se-enriched functional foods. PRACTICAL APPLICATION: The organic selenium black soybean (BS) produced by the germination method can be directly processed and eaten to improve human health. In addition, complexes of organic selenium, vitamin C, and γ-aminobutyric acid of germinated BS can be developed into functional substances and applied to food or health products as functional ingredient and/or natural antioxidant supplements.

Application of sodium selenate to cowpea (Vigna unguiculata L.) increases shoot and grain Se partitioning with strong genotypic interactions

BACKGORUND

Cowpea is a crop widely used in developing countries due its rusticity. Besides its rich genotypic variability, most breeding programs do not explore its potential to improve elements uptake. Selenium (Se) is a scarce element in most soils, resulting in its deficiency being common in human diets. This study aimed to evaluate the interaction between biofortification with Se and genotypic variation in cowpea, on the concentrations of Se in roots, leaves + stem and grains.

METHODS

Twenty-nine cowpea genotypes were grown in a greenhouse in the absence (control) and presence of Se (12.5 μg Se kg^-1 soil) as sodium selenate, in fully randomized scheme. The plants were cultivated until grains harvest. The following variables were determined: roots dry weight (g), leaves + stems dry weight (g), grains dry weight (g), Se concentration (mg kg^-1) in roots, leaves + stems and grains, and Se partitioning to shoots and grains.

RESULTS

Selenium application increased the Se concentration in roots, leaves + stems and grains in all genotypes. At least twofold variation in grain Se concentration was observed among genotypes. Selenium application did not impair biomass accumulation, including grain dry weight. Genotype "BRS Guariba" had the largest Se concentration in grains and leaves + stems. Genotype MNC04-795 F-158 had the largest partitioning of Se to shoots and grain, due to elevated dry weights of leaves + stems and grain, and high Se concentrations in these tissues.

CONCLUSION

This information might be valuable in future breeding programs to select for genotypes with better abilities to accumulate Se in grain to reduce widespread human Se undernutrition.

Selenium Accumulation, Speciation and Localization in Brazil Nuts (Bertholletia excelsa H.B.K.)

More than a billion people worldwide may be selenium (Se) deficient, and supplementation with Se-rich Brazil nuts may be a good strategy to prevent deficiency. Since different forms of Se have different nutritional value, and Se is toxic at elevated levels, careful seed characterization is important. Variation in Se concentration and correlations of this element with other nutrients were found in two batches of commercially available nuts. Selenium tissue localization and speciation were further determined. Mean Se levels were between 28 and 49 mg kg⁻¹, with up to 8-fold seed-to-seed variation (n = 13) within batches. Brazil nut Se was mainly in organic form. While present throughout the seed, Se was most concentrated in a ring 1 to 2 mm below the surface. While healthy, Brazil nuts should be consumed in moderation. Consumption of one seed (5 g) from a high-Se area meets its recommended daily allowance; the recommended serving size of 30 g may exceed the allowable daily intake (400 μg) or even its toxicity threshold (1200 μg). Based on these findings, the recommended serving size may be re-evaluated, consumers should be warned not to exceed the serving size and the seed may be sold as part of mixed nuts, to avoid excess Se intake.

Selenium in Germinated Chickpea (Cicer arietinum L.) Increases the Stability of Its Oil Fraction

Selenium is an essential mineral in human nutrition. In order to assess its effect on the stability of chickpea oil, seeds were germinated and tested with different amounts of sodium selenite (0.0, 0.5, 1.0 and 2.0 mg/100g seeds) for four days. Oil was extracted from sprouted chickpea and its physical properties, fatty acid profile (FAME), oxidative stability index (OSI), lipase and lipoxygenase (LOX) activities, cellular antioxidant activity (CAA), and phenolics and carotenoids were assessed and compared to chickpea seed oil. The amount of chickpea oil and its acid value (AV) increased during germination. The OSI increased by 28%, 46% and 14% for 0.5, 1.0 and 2.0 mg/100g compared with non-selenium treated sprouts. Phenolics increased up to 36% and carotenoids reduced by half in germinated sprouts with and without selenium compared to seeds. Carotenoids increased by 16% in sprouts treated with 1.0 mg/100 g selenium compared to their counterparts without selenium. FAME was not affected by treatments but samples with the highest selenium concentration increased lipase activity by 19% and decreased lipoxygenase activity by 55% compared with untreated sprouts. The CAA of oils increased by 43% to 66% in all germinated treatments compared with seeds. Results suggest that Se-enriched chickpea sprouts could represent an excellent source of oil with a high OSI and CAA, associated with a reduction in LOX activity and an increase in phenolics, respectively.

Rice seed priming with sodium selenate: Effects on germination, seedling growth, and biochemical attributes

The aim of this study was to determine the effects of sodium selenate (15, 30, 45, 60, 75, 90, and 105 mg kg⁻¹) on the germination and seedling growth of Changnongjing 1 rice (Oryza sativa L.) at 25 °C and 30 °C. Low selenate concentrations induced shorter and more uniform germination periods than did ultrapure water at both temperatures. Seedlings primed with low selenate concentrations were superior to those primed with ultrapure water in terms of plant height, fresh weight, dry matter accumulation, and soluble carbohydrate and protein contents. Lower selenate concentrations (15–75 mg kg⁻¹) induced higher chlorophyll and phenol contents in seedlings than did ultrapure water. Lower selenate concentrations also increased the superoxide dismutase (SOD), peroxidase (POX), catalase (CAT), and glutathione peroxidase (GPx) contents in seedlings and significantly decreased the stress-related malondialdehyde (MDA) content compared to ultrapure water. In conclusion, rice seedling germination and growth were promoted by priming with low selenate concentrations (15–75 mg kg⁻¹) but inhibited by priming with high selenate concentrations (90–105 mg kg⁻¹).