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1.
Molecules ; 25(24)2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33317196

RESUMO

The UV absorption spectra of six structurally related derivatives of anisole and veratrole, i.e., anisaldehyde, (E)-anethole, estragole, veratraldehyde, methyleugenol and (E)-methylisoeugenol, were recorded at various concentrations of the anionic surfactants, either sodium lauryl sulfate (SLS) or sodium lauryl ether sulfate (SLES) at T = 298 K. In addition, conductivity and density measurements were made for the SLS and SLES solutions to determine the volumetric properties of the studied surfactants. Next, using the W. Al-Soufi, L. Pineiro and M. Novo model (APN model) including the pseudo-phase model for micellar solubilization, the values of micelle-water partition coefficients for each perfume-surfactant system were determined. In addition, the relations between the molecular structures of the solute and the head group of the surfactant and the value of the micelle-water partition coefficient as well as the octanol-water one were discussed.


Assuntos
Anisóis/química , Ânions , Anisóis/isolamento & purificação , Micelas , Perfumes/química , Dodecilsulfato de Sódio/análogos & derivados , Dodecilsulfato de Sódio/química , Solubilidade , Soluções , Espectrofotometria Ultravioleta , Tensoativos/química , Água
2.
Plants (Basel) ; 11(16)2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-36015435

RESUMO

Sweet Birch (Betula lenta) has several economic and medicinal uses. Very little is known about the chemical composition of B. lenta. In this study, the volatile compositions of the bark of B. lenta from authentic and commercial sources were assessed by gas chromatography-mass spectrometry (GC-MS) and gas chromatography-flame ionization detection (GC-FID). Overall, more than 60 compounds were identified in natural sweet birch EO obtained by hydro-distillation. The oil was dominated by methyl salicylate (93.24-99.84%). A good approach to distinguishing wintergreen and birch oils would be biomarker-based analysis. The biomarkers are selected based upon three main criteria: (1) the marker should be commercially unavailable or too expensive which renders the adulteration process very costly, (2) The marker should be detected consistently in all the tested authentic EO samples, and (3) A birch EO marker should be found exclusively in birch EO, not in wintergreen and vice versa. The minor components o-guaiacol, veratrole, 2-E-4-Z-decadienal, and 2-E-4-E-decadienal were identified as natural marker compounds for authentic sweet birch oil. Surprisingly, none of the tested 27 commercial samples contained any of the identified birch markers. The detection of wintergreen markers such as vitispirane and ß-dehydroelsholtzia ketone, the synthetic marker dimethyl-2-hydroxyterephthalate, and ricenalidic acid lactone suggest the addition of wintergreen, synthetic methyl salicylate, and castor oil, respectively. This is the first report to identify birch biomarkers to the best of our knowledge.

3.
Spectrochim Acta A Mol Biomol Spectrosc ; 138: 357-69, 2015 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-25514662

RESUMO

This work deals with FT-IR, FT-Raman and FT-NMR spectral analysis and NBO, NLO, HOMO-LUMO and electronic transitions studies on veratrole. The molecular structure, fundamental vibrational frequencies and intensity of the vibrational bands were interpreted with the aid of structure optimizations and geometrical parameter calculations based on Hartree-Fock (HF) and density functional theory (DFT) method with 6-311++G(d, p) basis set. A study on the electronic properties, such as HOMO and LUMO energies were performed by time independent DFT approach. In addition, molecular electrostatic potential (MEP), Natural Bond-Orbital (NBO) analysis and thermodynamic properties were performed. The (1)H and (13)C nuclear magnetic resonance (NMR) chemical shifts of the molecule were calculated by gauge independent atomic orbital (GIAO) method and compared with experimental chemical shift.


Assuntos
Anisóis/análise , Espectroscopia de Ressonância Magnética , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Anisóis/química , Carbono/química , Simulação por Computador , Elétrons , Conformação Molecular , Estrutura Molecular , Oxigênio/química , Espectrofotometria Ultravioleta , Eletricidade Estática , Termodinâmica , Vibração
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