In order to contribute to the general understanding of the risks and benefits of consuming fish and fish products, total mercury (THg), monomethylmercury (MeHg), polychlorinated biphenyls (PCBs), ...selenium (Se),
n-3 and
n-6 fatty acids were determined in fresh and canned fish on the Slovenian market. Furthermore, the mercury exposure of pregnant women in Slovenia was assessed by determining total mercury (THg) in hair, and through fresh and canned fish consumption obtained by a food frequency questionnaire. Based on the frequency of fish consumption and levels of MeHg, THg and PCBs determined in the present study, it can be concluded that fish available on the Slovenian market do not represent a health risk. It was also confirmed that fish are important sources of selenium and
n-3 fatty acids.
Tartary buckwheat (Fagopyrum tataricum) is a semiwild plant grown in the Himalaya region. Due to its high concentration of flavonoids and trace elements it is of interest for cultivation in other ...countries as well. The feasibility of increasing the concentration of Se in grain and in green parts of Tartary buckwheat has not yet been investigated. The aim of this investigation was thus to determine the concentration of Se in different edible parts of Tartary buckwheat treated with different concentrations of Na selenate using different techniques. In plants grown in soil fertilized once with 0.5 and 10 mg Se L−1, Se was efficiently translocated from the roots to the leaves and seeds. Foliar spraying with 0.5 mg Se L−1 increased Se content in leaves and seeds. Among the edible parts of Tartary buckwheat plants the highest content of Se in control and in treated groups was found in leaves, followed by seeds and stems. Regarding recommended Se concentration, edible parts of Tartary buckwheat were safe for human consumption. Soil fertilization with 0.5 and 10 mg Se L−1 and foliar fertilization with 0.5 mg Se L−1 are applicable for cultivation of Tartary buckwheat as a functional food enriched with Se.
The interactions between the uptake of selenium (as selenite and selenate) and iodine (as iodate and iodide) by red chicory (
L. var.
Hegi) and their effects on selected morphological and ...physiological characteristics were investigated. Seedlings were transplanted to the field, and at the onset of head formation, the plants were foliar-sprayed with the following solutions: Milli-Q water (control), Se (IV), Se (VI), I (-I), I (V), Se (IV) + I (-I), Se (IV) + I (V), Se (VI) + I (-I) and Se (VI) + I (V). The different treatments had no significant effects on the yield (39.8-51.5 t ha
) and mass (970-1200 g) of the chicory heads. The selenium content in Se-treated plants was up to 5.5-times greater than the control plants. The iodine content in the chicory leaves enriched with I was 3.5-times greater than the control plants. Iodide or iodate, applied together with selenite in the spray solution, increased the uptake of Se by chicory plants, while both forms of iodine, applied together with selenate, reduced the uptake of Se. Plants treated with I (V) had lower amounts of chlorophyll
and carotenoids than the control, while respiratory potential was higher than the control, which indicated the possible presence of stress in I (V)-treated plants. However, the potential photochemical efficiency of photosystem II was similar and close to the theoretical maximum (0.83) in the control and treated groups, which indicated that all of the plants were in good condition. Furthermore, the plant mass and yield were comparable in the control and treated groups. Molecular studies, like gene expression analysis, would represent a major upgrade of the present study by defining the mechanisms of Se and I uptake and their interactions and by enhancing the knowledge of the Se and I transporters.
Ambient UV radiation is recognised as an important environmental factor in the regulation of plant growth and development, and selenium (Se) as a beneficial nutrient that can increase plant tolerance ...to different environmental constraints. The effects on hybrid buckwheat plants of full (+UV) and reduced (−UV) ambient UV radiation without (−Se) and with (+Se) foliar Se treatment (10 mg L
−1
sodium selenate) provided the four conditions of Se−UV-, Se-+UV, +Se−UV and +Se+UV. Plant morphological, biochemical and physiological properties were examined, along with leaf elemental composition and content, efficiency of Se enrichment, and production parameters. Leaf anatomical parameters under all conditions were mainly affected by UV radiation, and less so by Se. +Se+UV plants showed a trade-off between primary and secondary metabolism, which resulted in high levels of protective substances (e.g. anthocyanins, UV absorbing compounds), and low levels of photosynthetic pigments. All +UV plants were significantly shorter in comparison to those under the reduced −UV, while biomass production was highest for −Se+UV plants and lowest for +Se+UV plants. +Se plants accumulated ∼20-fold greater Se content compared to −Se plants, and full ambient UV radiation partly reduced this effect. +UV plants showed increased phosphorus content in leaves, independent of Se status, while +Se plants showed increased K content. Si content was increased by Se treatment and decreased by the full UV exposure. Se treatment and the ambient UV radiation, separately have positive effects on growth and production of this hybrid buckwheat, while the combination of the Se treatment and ambient UV resulted in lower yields. However, under these conditions (+Se+UV), the buckwheat plants established good protection against the different environmental constraints that are becoming more and more frequent due to changes to our climate.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The purpose of this study was to develop an analytical procedure for determination of the amount of total fluoride in total diet samples, including drinking water and beverages. Samples were taken by ...the duplicate portion technique and decomposed by alkali carbonate fusion using KNaCO
3, and the amount of fluoride in solution was determined by fluoride ion selective electrode using the multiple known addition technique. The mean amount of total fluoride determined in 20 total diet samples obtained from the Slovenian Military was 1.84
±
0.70
mg/kg on a dry matter basis. Accordingly the estimated daily intake was 1.50
±
0.56
mg.
Various biomarkers were used to assess selenium (Se) status during 3 months of basic military training in a group of recruits. Samples of whole blood and plasma or serum were taken from a group of ...conscripts three times: at the beginning (n = 15), in the middle immediately after a severely stressful physical activity (n = 15) and at the end of military training (n = 13). Selenium was determined in diet samples, blood, plasma and plasma protein fractions as selenoprotein P (SelP) and glutathione peroxidase (eGPx). Selenium was determined by hydride generation-atomic fluorescence spectrometry and fractionation of proteins performed by affinity chromatography. Total serum glutathione, erythrocyte and serum GPx activity were followed as well. The average Se intake was calculated according to meal consumption questionnaires and Se determined in composite diet samples, giving an assessed intake of 48 ± 10 μg/day. At all three samplings, the average blood Se concentration was within the framework of adequate supply (87 ± 12, 94 ± 15 and 80 ± 13 ng/g). Plasma Se was between 70 and 80 ng/g (71 ± 10, 79 ± 9 and 76 ± 10 ng/g), which is believed to enable the full expression of plasma GPx. The average shares of plasma Se proteins were 61 ± 6%, 58 ± 6% and 54 ± 9% for SelP and 27 ± 4%, 34 ± 7% and 29 ± 5% for GPx. Although the observed tendency of the increases of serum and erythrocyte GPx activities at the second and third samplings with respect to the first was statistically insignificant, it is still indicative of some protection against oxidative stress, while the decreasing SelP levels during training suggest a slowly decreasing biologically active selenium pool.
The elements selenium (Se) and iodine (I) are both crucial for the normal functioning of the thyroid. Biofortification with these elements is particularly feasible in areas where they show a deficit. ...Iodine and selenium can have positive effects on different plants when applied at the correct concentrations. The effects of their simultaneous addition on plant physiology and biochemistry, as well as on seed germination and sprout biomass, were studied in pumpkin (Cucurbita pepo L. ssp. pepo). To study the effect of Se and I on sprouts, sprouts were grown from seeds soaked in solutions of different forms of Se, I and their combination in the growth chamber experiment. In the field experiment, pumpkins plants were foliarly treated with the same concentrations and forms of Se and I. The combination of Se and I treatments enhanced the germination of the soaked seeds, with no significant differences between Se and I treatments for sprout mass. The yield of pumpkins and seed production were unaffected by Se and I foliar application. The anthocyanin levels and respiratory potential measured via the electron transport system’s activity showed different patterns according to treatments and plant parts (sprouts, leaves, seeds). The redistribution of Se and I from seeds to sprouts was significant. The accumulation of Se was higher in sprouts from the seeds treated with Se together with I, compared to sprouts from the seeds treated with Se alone. Interactions between Se and I were also noted in the seeds, which developed in the treated plants.
Low selenium (Se) status is associated with several diseases. International organizations have proposed intakes of Se for general populations, including infants. Studies of the association of Se ...concentration in breast milk and maternal diet have yielded inconsistent results. We evaluated the relation between the intake of food items during pregnancy and Se concentration in human milk after delivery and compared infant intake of Se from breast milk with the recommended intakes.
This cross-sectional study was part of the baseline assessment of a prospective cohort of Italian mother-child pairs enrolled in 1999-2001. Se concentration was measured in the milk of 100 women included in the cohort and correlated with the intake of food items during pregnancy and lactation as reported in a food frequency questionnaire.
Among foods consumed in pregnancy, only eggs had a positive, but weak, correlation with Se concentration in milk (r = 0.20, P = 0.04). Fish intake during lactation was also weakly correlated with Se in milk (r = 0.21, P = 0.04). Se content of breast milk in our population was lower than that noted in other international studies; however, very few children who were exclusively breastfed were estimated not to have met the recommended Se intake.
Future research should aim to verify whether infants in this part of Italy still meet the recommended nutrient intake of Se and to assess the influence of the concurrent diet of lactating mothers on the Se content of their milk.
The impact of selenium (Se) addition and UV radiation on Tartary buckwheat and hybrid buckwheat were studied. Both buckwheat species grew outdoors at the experimental field of the Biotechnical ...Faculty in Ljubljana. They were exposed to four different treatments regarding the UV radiation (ambient or reduced) and added Se (naturally accessible or foliary treated with Na selenate in concentration 10 mg Se L-1). The content of pigments (chlorophyll a and b, carotenoids, anthocyanins) and UV absorbing compounds, transpiration rate, photochemical efficiency of photosystem II (PS) II and respiratory potential were measured. At the end of experiment we determined the biomass of different plant parts. The results showed that irrespective of the buckwheat species the added Se lowered the content of chlorophyll a and carotenoids, while it increased the effective quantum yield of PS II and transpiration rate. UV radiation reduced the content of anthocyanins only. Se and UV-B radiation as independent factors exerted no impact on buckwheat yield. Hybrid buckwheat had a higher physiological activity than the Tartary buckwheat yet a smaller biomass of plant parts, including reduced yield. Ambient UV radiation had a slightly negative impact on hybrid buckwheat while it had no noticeable negative impact on Tartary buckwheat. The Se treated Tartary and hybrid buckwheat were suitable for human andanimal diet regarding to Se concentrations in leaves and grains.
Pumpkins were treated by spraying the leaves in the flowering period with a water solution containing 1.5 mg Se per liter in the form of Na2SeO4. The average total selenium content of seeds was found ...to be 0.19 µg g-1 in nontreated pumpkins and 1.1 µg g-1 in exposed ones. For speciation analysis, enzymatic hydrolysis with different amounts of Protease XIV was carried out. Under optimal conditions of enzymatic hydrolysis, 90% of the total selenium was found in soluble forms. Separation of species was performed using HPLC on anion and cation exchange columns and for detection UV-HG-AFS was applied. In enzymatic hydrolysis extracts, the main fraction of selenium was bound as selenomethionine (SeMet), representing on average of 81 ± 8% of the total Se content in the sample.
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