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Sprouts enriched with selenium offer increased nutritional value and chemopreventive properties raising interest in their contribution to the human diet. The effect of selenium depends on its concentration and the chemical forms. The aims of this study were: to synthesize several novel organic selenium compounds (selenoesters), to examine how effectively they can deliver selenium to Brassica sprouts, and investigate their metabolism in sprouts. We revealed that selenium content in the fortified sprouts was several orders of magnitude higher than in the unfortified ones. There were significant differences between doses of selenium delivered to sprouts by different selenium compounds. A small percentage of supplemented selenium (<10%) was incorporated into the sprouts as seleno-L-methionine, Se(IV) and Se-methylselenocysteine, while several other low molecular weight selenium species were also identified, in different proportions, depending on the compound used in the fortification procedure. In conclusion: novel selenorganic compounds were successfully applied to fortify kale sprouts in selenium. The detection, screening, and characterization (including structure elucidation) of their low molecular weight metabolites and derivatives have previously been unreported in Brassica genus.

© 2020 by the authors. Although nickel allergy and carcinogenicity are well known, their molecular mechanisms are still uncertain, thus demanding studies at the molecular level. The nickel carcinogenicity is known to be dependent on the chemical form of nickel, since only certain nickel compounds can enter the cell. This study investigates, for the first time, the cytotoxicity, cellular uptake, and molecular targets of nickel nanoparticles (NiNPs) in human skin cells in comparison with other chemical forms of nickel. The dose-response curve that was obtained for NiNPs in the cytotoxicity assays showed a linear behavior typical of genotoxic carcinogens. The exposure of keratinocytes to NiNPs leads to the release of Ni2+ ions and its accumulation in the cytosol. A 6 kDa nickel-binding molecule was found to be synthesized by cells exposed to NiNPs at a dose corresponding to medium mortality. This molecule was identified to be tumor-related p63-regulated gene 1 protein.

Heat-resistant steels of HP series (Fe-25Cr-35Ni) are used in high temperature structural applications. Their composition include Nb as strong carbide former. Electron Backscatter Diffraction (EBSD) investigations revealed that, in the as-cast condition, alloys exhibit austenitic matrix with intergranular primary carbides such as MC, M23C6 and/or M7C3. During exposure at a high temperature, phase transformations occurred: chromium carbides of M7C3 type transform into the more stable M23C6 type, intergranular M23C6 carbides precipitate, and Lave phase due to increase of Niobium activity with temperature increase, as thermodynamic simulation confirmed. Therefore, combination of EBSD-EDS technique with thermodynamic calculation is one of the novel and most accurate method to investigation of phase transformation, as the precipitations are identified on the basis of their crystal structure, chemical composition and their thermodynamic features.

Amorphous hydrogenated silicon carbide (a-SiCx:H) coatings were deposited on stainless steel 301 (SS301) using plasma enhanced chemical vapor deposition with the methane gas flow ranging from 30 to 90 sccm. XRD spectra confirmed the amorphous structure of these coatings. The as-deposited coatings all exhibited homogenous dense feature, and no porosities were observed in SEM and AFM analysis. The a-SiCx:H coatings remarkably increased the corrosion resistance of the SS301 substrate. With the increase of the C concentration, the a-SiCx:H coatings exhibited significantly enhanced electrochemical behavior. The a-SiCx:H coating with the highest carbon concentration acted as an excellent barrier to charge transfer, with a corrosion current of 3.5 × 10−12 A/cm2 and a breakdown voltage of 1.36 V, compared to 2.5 × 10−8 A/cm2 and 0.34 V for the SS301 substrate.