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In this study, the in vitro effects of different Se concentrations (5, 10, 15, 20, and 100 mg kg−1) from different Se forms (sodium selenite, sodium selenate, selenomethionine, and selenocystine) on the development of a Fusarium proliferatum strain isolated from rice were investigated. A concentration-dependent effect was detected. Se reduced fungal growth starting from 10 mg kg−1 and increasing the concentration (15, 20, and 100 mg kg−1) enhanced the inhibitory effect. Se bioactivity was also chemical form dependent. Selenocystine was found to be the most effective at the lowest concentration (5 mg kg−1). Complete growth inhibition was observed at 20 mg kg−1 of Se from selenite, selenomethionine, and selenocystine. Se speciation analysis revealed that fungus was able to change the Se speciation when the lowest Se concentration was applied. Scanning Electron Microscopy showed an alteration of the fungal morphology induced by Se. Considering that the inorganic forms have a higher solubility in water and are cheaper than organic forms, 20 mg kg−1 of Se from selenite can be suggested as the best combination suitable to inhibit F. proliferatum strain. The addition of low concentrations of Se from selenite to conventional fungicides may be a promising alternative approach for the control of Fusarium species.

Large amounts of chemical fertilizers are still currently used to compensate the soil nutrients scarcity in order to increase and sustain crop yield with consequent rising of environmental pollution and health problems. To mitigate these environmental risks, fertilizers with slow-release behaviours have been developed. The aim of this study was to assess the agronomic potential of two different glass-based materials (by-products from the ceramic sector) as inorganic slow-release iron (Fe) fertilizers.The X-ray powder diffraction confirmed the presence of amorphous structure and the richness in Fe of the investigated materials. The solubility analysis highlighted the slow Fe release from the glassy network and that the maximum of the Fe release was at alkaline pH suggesting their potential use as slow-release Fe fertilizers, especially in calcareous soils. The pot and leaching experiments demonstrated that although the glass-based materials increased the amount of soil available Fe, we did not observe Fe leaching and plant toxicity. This fact would suggest their reliability to increase soil fertility without negative effects on the environment.The use of glass-based materials, specifically by-products from the ceramic sectors, as inorganic slow-release Fe fertilizers can be sustained. The tests performed at three different pH conditions testified the slow-release behaviour of the tested materials and underlined that the Fe release increases at alkaline environment. Therefore, the present study pointed out the glass-based materials by products from the ceramic sector as novel slow-release and environmental-friendly fertilizers in agriculture. © 2021 The Authors. Journal of The Science of Food and Agriculture published by John WileySons Ltd on behalf of Society of Chemical Industry.

Salt stress and selenium are known to elicitate the production of plant secondary metabolites with antioxidant properties. On this basis, maize grains obtained from mother plants fertilized or not fertilized with selenium were sprouted at different levels of salinity (0, 25, and 50 mM NaCl) to evaluate the effects on the sprout yield, inorganic and organic Se species, minerals, and secondary metabolites, as revealed by a metabolomics analysis. Grain endogenous selenium (135 mg kg-1 vs. 0.19 mg kg-1 of the non-enriched grain) and salinity affected the sprout yield and composition, with salinity having the greatest effect on secondary metabolites. Most of the Se in sprouts was in an inorganic form, despite Se-enriched grains only containing organic Se. Some synergic effect was observed between Se and salinity. The best combination was obtained with Se-enriched grains sprouted at 25 mM NaCl, since this provided a good yield (not lower than in the untreated control), while sprout shoots were enriched in selenocystine and pro-nutritional semipolar compounds with antioxidant properties. Therefore, using grains from Se-fertilized crops and sprouting them under mild salt stress might represent a promising technique for improving the nutritional value of sprouts.

Selenium (Se) is an important micronutrient for living organisms, since it is involved in several physiological and metabolic processes. Se intake in humans is often low and very seldom excessive, and its bioavailability depends also on its chemical form, with organic Se as the most available after ingestion. The main dietary source of Se for humans is represented by plants, since many species are able to metabolize and accumulate organic Se in edible parts to be consumed directly (leaves, flowers, fruits, seeds, and sprouts) or after processing (oil, wine, etc.). Countless studies have recently investigated the Se biofortification of plants to produce Se-enriched foods and elicit the production of secondary metabolites, which may benefit human health when incorporated into the diet. Moreover, feeding animals Se-rich diets may provide Se-enriched meat. This work reviews the most recent literature on the nutraceutical profile of Se-enriched foods from plant and animal sources. Fil: D'Amato, Roberto. Università di Perugia; Italia Fil: Regni, Luca. Università di Perugia; Italia Fil: Falcinelli, Beatrice. Università di Perugia; Italia Fil: Mattioli, Simona. Università di Perugia; Italia Fil: Benincasa, Paolo. Università di Perugia; Italia Fil: Dal Bosco, Alessandro. Università di Perugia; Italia Fil: Pacheco, Pablo Hugo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Química de San Luis. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Química de San Luis; Argentina Fil: Proietti, Primo. Università di Perugia; Italia Fil: Troni, Elisabetta. Università di Perugia; Italia Fil: Santi, Claudio. Università di Perugia; Italia Fil: Businelli, Daniela. Università di Perugia; Italia

Nanosized α-zirconium phosphate, α-ZrP, undergoes a phase transition at 120 °C, which is not observed with microcrystalline α-ZrP in the same conditions, and which leads to a new 3D phase. The new compound, with formula Zr(HPO4)2 (τ'-ZrP), consists of cubelike nanoparticles and has a tetragonal unit cell (space group P43212, a = 7.955 Å, c = 10.744 Å). The structure of τ'-ZrP is in close relationship with that of the already known τ-ZrP. Both structures are made of packed chains of eight-membered rings, composed of Zr atoms connected to bridging HPO4 groups. The main difference between the two structures concerns the different orientation of the uncoordinated P-OH groups, pointing into the channels. The in situ XRPD analysis on nanosized α-ZrP, performed at 120 °C as a function of time, provided information about the kinetics of the formation of τ'-ZrP, showing that the α-ZrP phase is directly transformed into τ'-ZrP. Moreover, τ'-ZrP is converted into α-ZrP at room temperature in the presence of water vapor. It was proved that the free phosphoric acid, which is originally present in small amounts in nanosized α-ZrP and τ'-ZrP, is necessary for the interconversion between the two phases. As a matter of fact, the removal of phosphoric acid, by washing α-ZrP and τ'-ZrP with anhydrous ethanol, inhibits the above conversion.

Crystallite formation in membranes cast from sulfonated poly(etheretherketone) (SPEEK) dispersions in dimethylacetamide has been investigated by differential scanning calorimetry. The crystallites melt at 220 °C and the melting enthalpy (ΔHm) is strongly influenced by environmental conditions of solvent evaporation. When solvent is evaporated in air, ΔHm decreases with increasing the evaporation temperature so that no crystallites are formed above 45 °C. The study of crystallite formation at 30 °C, under controlled relative humidity (RH) and solvent evaporation rate, has shown that ΔHm decreases i) with decreasing RH from 75% to 5%, at constant evaporation rate, and ii) with increasing evaporation rate, especially at low RH. The exchange of protons with sodium ions results in an increase of the crystallite melting temperature thus indicating the presence of sulfonic groups in the crystallites. In comparison with crystallite-free SPEEK membranes, the presence of crystallites turns out in enhanced membrane mechanical properties, reduced hydration in liquid water above 75 °C, strongly anisotropic swelling (occurring mainly in the through-plane direction) and better performance in H2/air fuel cell at 70 °C.

The formation of layered zirconium phosphate phenylphosphonates, Zr(O3POH)(2-x)(O3PC6H5)(x) (hereafter ZP(PP)(x), with x in the range 0-2.0) from precursor solutions of zirconyl propionate, phosphoric and/or phenylphosphonic acids was studied by using NMP as solvent. On the basis of this investigation, composite membranes made of a SPEEK matrix (EW = 625, hereafter FUM) filled with ZP(PP)(x), with x = 0, 0.72 and 2.0 and filler loading up to 36 wt%, were prepared by casting mixtures of the precursor solution and a FUM dispersion in NMP. All the composite membranes exhibited lower swelling in water than FUM up to 110 degrees C, and, among them, the membrane with 32 wt% ZP(PP) 0.72 (hereafter FUM/ZP(PP)(0.72)-32) showed the lowest water uptake and the highest Young's modulus, with a proportional increase up to 60% with respect to FUM, at 70 degrees C and 80% relative humidity (RH). At 80 degrees C, the proton conductivity of all the composites decreased with increasing filler loading, and FUM/ZP(PP)(0.72)-32 was less conductive than FUM by a factor of similar to 5, both at 50% and 95% RH. However, differently from FUM, the conductivity of FUM/ZP(PP)(0.72)-32 turned to be stable over time even at 110 degrees C in the presence of liquid water, being around 0.1 S cm(-1).

Gels of alfa-type zirconium(IV) phosphate alkylphosphonates, ZP(C n)x, were prepared by reacting, at room temperature, propanol intercalated nanosized alfa-zirconium phosphate (?-ZrP) with propanol solutions of alkylphosphonic acids (H2Cn, n = number of carbon atoms in the alkyl chain = 4, 5, 6), with (H2C n/Zr) molar ratios in the range 0.4-4.0. 31P MAS NMR showed the presence of resonances due to the phosphate and phosphonate groups bonded to the Zr atoms mainly by three oxygen atoms, as in the ?-type layer. The composition of the ZP(Cn)x materials, obtained by thermogravimetric analysis, ranges from x ? 0.2 to x ? 1.1. On the basis of the NMR data and of the analysis of the X-ray patterns of gels and powders, it is inferred that the ZP(Cn)x compounds have an ?-type layered structure and that the reaction between alfa-ZrP and H2Cn is a topotactic anion exchange process. The evolution of the X-ray patterns during propanol deintercalation is consistent with a random distribution of the alkylphosphonate groups on the ?-type layers which gives rise to porous pathways in the interlayer region. To test the possibility of using ZP(Cn)x as mechanical reinforcement of a polymer matrix, a starch membrane filled with 5 wt % ZP(C6) 0.54 was prepared and characterized by stress-strain mechanical tests. Besides an excellent flexibility, this membrane exhibited a proportional increase of the Young's modulus by 230% in comparison with neat starch.

Simple addition of zirconyl propionate to phosphoric acid in alcoholic media surprisingly led to the formation, in few minutes, of transparent gels containing solvent intercalated zirconium phosphate (ZrP) nanoparticles with hexagonal shape and a planar size of about 40 nm. With the help of elemental analysis, inductively coupled plasma-optical emission spectrometry (ICP-OES), and P-31 magic angle spinning (MAS) NMR, the nanoparticle composition was formulated as Zr(R)(w)-(HPO4)(x)(H2PO4)(y), in which R can be an hydroxyl or a propionate group. The stoichiometric coefficients for propanol intercalated ZrP are x = 1.43, y = 0.83, and w = 0.32. Solvent elimination at 60 degrees C gave rise to an increase in the x value and a decrease in the y and w values. X-ray powder diffraction analysis and transmission electron microscopy (TEM) observations showed a concomitant increase in the particle size: planar size and thickness ranged from 90 to 200 nm and from 20 to 85 nm, respectively, depending on the nature of the solvent. A possible mechanism explaining the change in the x, y, and w values, the growth of nanoparticles, and the role of the solvent is proposed. Finally, the possibility of using these gels to disperse the ZrP nanoparticles within the polymer matrix of Nafion117 is shown.