Potato Chips Byproducts as Feedstocks for Developing Active Starch-Based Films with Potential for Cheese Packaging

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Comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry combined with solid phase microextraction as a powerful tool for quantification of ethyl carbamate in fortified wines. The case study of Madeira wine

An analytical methodology based on headspace solid phase microextraction (HS-SPME) combined with comprehensive two-dimensional gas chromatography—time-of-flight mass spectrometry (GC × GC–ToFMS) was developed for the identification and quantification of the toxic contaminant ethyl carbamate (EC) directly in fortified wines. The method performance was assessed for dry/medium dry and sweet/medium sweet model wines, and for quantification purposes, calibration plots were performed for both matrices using the ion extraction chromatography (IEC) mode (m/z 62). Good linearity was obtained with a regression coefficient (r2) higher than 0.981. A good precision was attained (R.S.D. <20%) and low detection limits (LOD) were achieved for dry (4.31 μg/L) and sweet (2.75 μg/L) model wines. The quantification limits (LOQ) and recovery for dry wines were 14.38 μg/L and 88.6%, whereas for sweet wines were 9.16 μg/L and 99.4%, respectively. The higher performance was attainted with sweet model wine, as increasing of glucose content improves the volatile compound in headspace, and a better linearity, recovery and precision were achieved. The analytical methodology was applied to analyse 20 fortified Madeira wines including different types of wine (dry, medium dry, sweet, and medium sweet) obtained from several harvests in Madeira Island (Portugal). The EC levels ranged from 54.1 μg/L (medium dry) to 162.5 μg/L (medium sweet)

Assessment of the sesquiterpenic profile of Ferula gummosa oleo-gum-resin (galbanum) from Iran. Contributes to its valuation as a potential source of sesquiterpenic compounds

The sesquiterpenic composition of the essential oil of Iranian oleo-gum-resin Ferule gummosa Boiss was studied by comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry (GC x GC-ToFMS). A total of 106 sesquiterpenic compounds, including 61 hydrocarbons, 29 alcohols, 2 aldehydes, 10 oxides, 2 ketones, 1 furan, and 1 epoxide, were tentatively identified. From these, 68 are reported for the first time in F. gummosa species. Moreover, the most abundant sesquiterpenic compounds detected were the alcohols bulnesol, alpha-eudesmol, and alpha-bisabolol. This work allowed to achieve a deep characterization of the sesquiterpenic composition of F. gummosa oil, a crucial step in the bioprospection of this biomass plant material as a source of sesquiterpenic compounds. Furthermore, this approach can promote the market confidence allowing a more efficient quality control and preventing adulterations. (C) 2012 Elsevier B.V. All rights reserved

Acute toxicity of single and combined rare earth element exposures towards Daphnia similis

The increasing use of Rare Earth Elements (REE) in emerging technologies, medicine and agriculture has led to chronic aquatic compartment contamination. In this context, this aimed to evaluate the acute toxic effects of lanthanum (La), neodymium (Nd) and samarium (Sm), as both single and binary and ternary mixtures on the survival of the microcrustacean Daphnia similis. A metal solution medium with (MS) and without EDTA and cyanocobalamin (MSq) as chelators was employed as the assay dilution water to assess REE bioavailability effects. In the single exposure experiments, toxicity in the MS medium decreased following the order La > Sm > Nd, while the opposite was noted for the MSq medium, which was also more toxic than the MS medium. The highest MS toxicity was observed for the binary Nd + La (1:1) mixture (EC50 48 h of 11.57 ± 1.22 mg.L−1) and the lowest, in the ternary Sm + La + Nd (2:2:1) mixture (EC50 48 h 41.48 ± 1.40 mg.L−1). The highest toxicity in the MSq medium was observed in the single assays and in the binary Sm + Nd (1:1) mixture (EC50 48 h 10.60 ± 1.57 mg.L−1), and the lowest, in the ternary Sm + La + Nd (1:2:2) mixture (EC50 48 h 36.76 ± 1.54 mg.L−1). Concerning the MS medium, 75 % of interactions were additive, 19 % antagonistic, and 6 % synergistic. In the MSq medium, 56 % of interactions were synergistic and 44 % additive. The higher toxicity observed in the MSq medium indicates that the absence of chelators can increase the concentrations of more toxic free ions, suggesting that the MS medium should be avoided in REE assays. Additive interactions were observed in greater or equivalent amounts in both media and were independent of elemental mixture ratios. These findings improve the understanding of environmental REE effects, contributing to the establishment of future guidelines and ecological risk calculations

Organometallic iridium catalysts based on pyridinecarboxylate ligands for the oxidative splitting of water

Organometallic compounds [Cp*Ir(κ2-N,O)X] (κ2-N,O = 2-pyridinecarboxylic acid, ion(−1) (1), 2,4-pyridinedicarboxylic acid, ion(−1) (2), 2,6-pyridinedicarboxylic acid, ion(−1) (3); X– = Cl– ( a ), NO3– (b)) and [Ir(κ3-N,O,O)(1-κ-4,5-η2-C8H13)(MeOH)] (κ3-N,O,O = 2,6-pyridinedicarboxylic acid, ion(−2) (4)) are effective catalysts for the oxidative splitting of water to O2 driven by Ce4+. They show similar TOFLT values (long-term TOF, 2.6–7.4 min–1) while TOFIN values (initial TOF) strongly depend on the catalyst (1 ≫ 2 > 3 > 4), reaching a maximum value of 287 min–1 (4.8 s–1) for 1a , which is the highest TOF value ever reported for an iridium catalyst. Voltammetric measurements indicate that the oxidative processes of compounds 1–4 are located at values substantially less positive than that of [Cp*Ir(bzpy)NO3] (bzpy = 2-benzoylpyridine; ΔE ≈ 0.2–0.3 V), taken as reference catalyst for water oxidation. In particular, compound 3, having a pendant −COOH moiety in close proximity to an iridium coordination site, as shown by the structure determined by single-crystal X-ray diffraction, exhibits several low-potential oxidation processes