Late harvest (LHW) and ice harvest (IHW) Gewürztraminer wine samples from Croatia (Ilok) were investigated. Their technological parameters, chromaticity coordinates, total phenols content, and antioxidant capacity were determined. 5-(Hydroxymethyl)furfural, xanthine, and trans-caftaric acid were analyzed in the samples by high performance liquid chromatography (HPLC-DAD). Headspace solid-phase microextraction (HS-SPME) followed by gas chromatography and mass spectrometry (GC/MS) analysis revealed isoamyl alcohol as predominant compound (21.25 - 60.30%). Diethyl succinate, 2-phenylethanol, and benzaldehyde were also abundant. Ethyl octanoate (1.48 - 5.70%) and ethyl caprate (0.48 - 4.83%) decreased significantly in LHW, being the lowest in IHW. Two solvents were applied for the samples extraction (solvent A - pentane/diethyl ether 1:2 (v/v) and solvent B - dichloromethane), and the extracts were analyzed by GC/MS. Ethyl hydrogen succinate (solvent A: 27.30 - 52.04%; solvent B: 28.04 - 46.69%) and diethyl succinate (solvent A: 5.21 - 18.2%; solvent B: 2.66 - 7.72%) were predominant in IHW and LHW. Aromatic alcohols were also found: 2-phenylethanol (solvent A: 7.07 - 21.09%; solvent B: 5.50 - 11.82%), 4-hydroxybenzyl alcohol (solvent A: 1.45 - 6.68%; solvent B: 2.47 - 12.16%) and benzyl alcohol (solvent A: 0.10 - 0.77%). The obtained results complement a previous study on IHW (Gewürztraminer) from Croatia providing new features and indicating great chemical diversity among the samples.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1002/cbdv.201800254 | DOI Listing |
Phys Rev Lett
December 2024
Laboratoire PHENIX, Sorbonne Université, CNRS, (Physico-Chimie des Electrolytes et Nanosystèmes Interfaciaux), 4 Place Jussieu, 75005 Paris, France.
In recent years, the theoretical description of electrical noise and fluctuation-induced effects in electrolytes has gained renewed interest, enabled by stochastic field theories like stochastic density functional theory (SDFT). Such models, however, treat solvents implicitly, ignoring their generally polar nature. In the present study, starting from microscopic principles, we derive a fully explicit SDFT theory that applies to ions in a polar solvent.
View Article and Find Full Text PDFProbiotics Antimicrob Proteins
January 2025
Faculty of Pharmacy and Medical Sciences, University of Petra, Amman, 11196, Jordan.
Prebiotics, traditionally linked to gut health, are increasingly recognized for their systemic benefits, influencing multiple organ systems through interactions with the gut microbiota. Compounds like inulin, fructooligosaccharides (FOS), and galactooligosaccharides (GOS) enhance short-chain fatty acid (SCFA) production, benefiting neurocognitive health, cardiovascular function, immune modulation, and skin integrity. Advances in biotechnology, including deep eutectic solvents (DES) for extraction and machine learning (ML) for personalized formulations, have expanded prebiotic applications.
View Article and Find Full Text PDFInorg Chem
January 2025
NUPOM Lab, Chemistry, School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne NE1 7RU, U.K.
An understanding of proton transfer and migration at the surfaces of solid metal oxides and related molecular polyoxometalates (POMs) and metal alkoxides is crucial for the development of reactivity involving protonation or the absorption/binding of water. In this work, the hydrolysis of alkoxido Ti- and Sn-substituted Lindqvist [(MeO)MWO] (M = Ti, ; M = Sn, ) and Keggin [(MeO)MPWO] (M = Ti, ; M = Sn, ) type polyoxometalates (POMs) to hydroxido derivatives and subsequent condensation to μ-oxido species has been investigated in detail to provide insight into proton transfer reactions in these molecular metal oxide systems. Solution NMR studies revealed the dependence of reactions not only on the nature of the heteroatom (Ti or Sn) but also on the type of lacunary (W or PW) POM and also on the solvent (MeCN or DMSO).
View Article and Find Full Text PDFJ Phys Chem B
January 2025
Institute of Nanotechnology, Karlsruhe Institute of Technology (KIT), Kaiserstraße 12, 76131 Karlsruhe, Germany.
Implicit solvation models permit the approximate description of solute-solvent interactions, where water is the most often considered solvent due to its relevance in biological systems. The use of other solvents is less common but is relevant for applications such as in nuclear magnetic resonance (NMR) or chromatography. As an example, chloroform is commonly used in anisotropic NMR to measure residual dipolar couplings (RDCs) of chiral analytes weakly aligned by an alignment medium.
View Article and Find Full Text PDFChemistry
January 2025
Central University of Gujarat, School of Chemical Sciences, Sector 30, 382030, Gandhinagar, INDIA.
The selective synthesis of 4-alkyl/aryl-3H-1,2-dithiole-3-thione in THF and water-dependent switchable product ketothioamide is demonstrated. The presented method describes explicitly the synthesis of the extremely rare positional isomer 4-alkyl/aryl-3H-1,2-dithiole-3-thione, a unique structure distinct from another positional isomer, 5-alkyl/aryl-3H-1,2-dithiole-3-thione. The unique umpolung of the nitromethyl group is exploited for solvent selective nucleophilic sulfur and amine addition.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!