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1.
J Agric Food Chem ; 72(14): 8081-8091, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38535975

RESUMO

Culinary sage, Salvia officinalis L., is a popular spice plant commonly used throughout the world. In this study, 35 odorants were identified in dried sage via solvent-assisted flavor evaporation (SAFE) and aroma extract dilution analysis (AEDA), including 9 that were identified in sage for the first time. Fifteen odorants were quantitated by stable isotope dilution analysis (SIDA), and their odor activity values (OAVs) were determined. Odorants with high OAVs included (2E,6Z)-nona-2,6-dienal, 1,8-cineole, and ß-myrcene. A formulated aroma simulation model closely matched the aroma profile of an aqueous infusion of dried sage. Enantiomeric proportions of selected odorants were determined by chiral gas chromatography. Furthermore, 6 different sage cultivars were grown in the greenhouse, dried under the same conditions, and analyzed. Sensory analysis determined that all cultivars were dominated by an herbaceous sensory attribute and had varying intensities of eucalyptus, mint, clove, pine, green, earthy, floral, and citrus notes. Cultivars with varying intensities of herbaceous, eucalyptus, pine, and green sensory notes correlated with the OAVs of α-thujone/ß-thujone, 1,8-cineole, α-pinene, and (2E,6Z)-nona-2,6-dienal, respectively. This study identified the odorants driving the sensory profiles of different sage cultivars and serves as a foundation for future studies on the aroma chemistry of culinary sage.


Assuntos
Salvia officinalis , Compostos Orgânicos Voláteis , Odorantes/análise , Eucaliptol/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Cromatografia Gasosa , Compostos Orgânicos Voláteis/química , Aromatizantes/química , Olfatometria
2.
J Agric Food Chem ; 71(42): 15723-15731, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37823576

RESUMO

Chardonnay marc, a co-product of the wine making industry, has recently garnered attention due to its health-promoting properties and is growing in popularity as a potential healthy and flavorful food ingredient. While previous studies have characterized the odorants in marc skins and identified the key odorants in marc seeds, the key odorants in the skins and stems and the contribution of each component to the whole marc aroma remains unknown. In this study, 27 odorants were identified in marc stems using solvent-assisted flavor evaporation and aroma extract dilution analysis. Four odorants were quantitated employing stable isotope dilution assays, and odor activity values (OAVs) were calculated. An odor simulation model prepared using odorants with OAVs > 1 sensorially matched the aroma of the marc stems. Omission studies showed that 3-methylnonane-2,4-dione, ethyl octanoate, oct-1-en-3-one, (2E,4E)-deca-2,4-dienal, (2E,4E)-nona-2,4-dienal, ß-ionone, linalool, hexanal, HDMF, and 3-(methylsulfonyl)propanal were the key odorants in marc skins, while hexanal and 3-methylnonane-2,4-dione were the key odorants in marc stems. Mass balance studies suggested that the skins were the main contributor to the hay, floral, and fruity attributes of the whole marc, the seeds contributed mostly to the fatty attribute, and the stems had a minor contribution.


Assuntos
Compostos Orgânicos Voláteis , Vinho , Odorantes/análise , Vinho/análise , Cromatografia Gasosa-Espectrometria de Massas , Olfatometria , Sementes/química , Compostos Orgânicos Voláteis/análise , Aromatizantes/análise
3.
Dalton Trans ; 52(39): 13868-13871, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37751280

RESUMO

Addition of 2 equiv. of bis(diisopropylamino)cyclopropenylidene (BAC) to [U(NR2)3(CCPh)] (1, R = SiMe3), in Et2O, results in formation of [cyclo-N(iPr)C(Me)2CH(NiPr2)C{CHC3(NiPr2)2}][U(NR2)2(N(SiMe3)SiMe2CH2)(CCPh)] (2) in moderate isolated yield. Complex 2 is the result of coupling and protonation of two BAC molecules, where complex 1 contributes the required proton. It was characterized by NMR spectroscopy and X-ray crystallography and represents a new mode of reactivity of the cyclopropenylidene fragment.

4.
Inorg Chem ; 62(16): 6447-6457, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37053543

RESUMO

The reaction of 1 equiv of 1-azidoadamantane with [UIII(NR2)3] (R = SiMe3) in Et2O results in the formation of [UV(NR2)3(NAd)] (1, Ad = 1-adamantyl) in good yields. The electronic structure of 1, as well as those of the related U(V) complexes, [UV(NR2)3(NSiMe3)] (2) and [UV(NR2)3(O)] (3), were analyzed with EPR spectroscopy, SQUID magnetometry, NIR-visible spectroscopy, and crystal field modeling. This analysis revealed that, within this series of complexes, the steric bulk of the E2- (E═O, NR) ligand is the most important factor in determining the electronic structure. In particular, the increasing steric bulk of this ligand, on moving from O2- to [NAd]2-, results in increasing U═E distances and E-U-Namide angles. These changes have two principal effects on the resulting electronic structure: (1) the increasing U═E distances decreases the energy of the fσ orbital, which is primarily σ* with respect to the U═E bond, and (2) the increasing E-U-Namide angles increases the energy of fδ, due to increasing antibonding interactions with the amide ligands. As a result of the latter change, the electronic ground state for complexes 1 and 2 is primarily fφ in character, whereas the ground state for complex 3 is primarily fδ.

5.
Inorg Chem ; 59(15): 11079-11088, 2020 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-32698569

RESUMO

The synthesis and characterization of V(═O){N(SiMe3)2}3 (1), V(═NSiMe3){N(SiMe3)2}3 (2), and V(═NSiMe3)(OSiMe3){N(SiMe3)2}2 (3) are described. Prior attempts to synthesize the vanadium(V) oxo complex 1 via salt metathesis of VOCl3 with the lithium or sodium silylamide salt had yielded either the putative rearranged species V(═NSiMe3)(OSiMe3){N(SiMe3)2}2 (3) or the oxo-bridged, dimetallic {(µ-O)2V2[N(SiMe3)2]4}. We now show that complex 1 is available by treatment of the vanadium(III) tris(silylamide) V{N(SiMe3)2}3 with iodosylbenzene. The imido complex 2 was obtained by treatment of V{N(SiMe3)2}3 with trimethylsilyl azide. Sublimation of 1 formed complex 3, which was determined to be V(═NSiMe3)(OSiMe3){N(SiMe3)2}2, on the basis of infrared, electronic, and 1H and 51V NMR spectroscopies. Crystallographic disorder precluded a complete structural characterization of 3, although a four-coordinate V atom, as well as severely disordered ligands, were apparent. Comparison of the vibrational spectra of 1 and 2 allowed an unambiguous assignment of the V-O (995 cm-1) and V-Nimide (1060 cm-1) stretching bands. The vibrational spectrum of complex 3 displayed strong absorbances at 1090 and 945 cm-1, indicative of its metal imide and metal siloxide moieties. The 1H NMR spectrum of 1 in deuterated benzene showed overlapping signals for the ligand protons proximal and distal to the oxo moiety at 0.52 and 0.38 ppm. The 1H NMR spectrum of 2 in deuterated methylene chloride displayed distinct signals for the imido (0.41 ppm) and amido (0.35 ppm) protons, whereas 1H NMR spectroscopy of 3 showed three signals in an intensity ratio consistent with the formula V(═NSiMe3)(OSiMe3){N(SiMe3)2}2. 51V NMR spectra of 1-3 revealed singlet resonances at -119 ppm (1), -24 ppm (2), and -279 ppm (3). The electronic spectra of 1-3 displayed single absorbances in the charge transfer region, consistent with their d0 electron configurations. Kinetic studies of the spontaneous conversion of complex 1 to 3 were used to determine the rate constants (ca. 0.0002 s-1 (63 °C), 0.0006 s-1 (73 °C), 0.002 s-1 (83 °C)) and activation energy (ca. 20 kcal/mol) of this first-order process.

6.
Pediatrics ; 136(1): 18-27, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26034246

RESUMO

BACKGROUND: The relationship between the alcohol policy environment (ie, the combined effectiveness and implementation of multiple existing alcohol policies) and youth drinking in the United States has not been assessed. We hypothesized that stronger alcohol policy environments are inversely associated with youth drinking, and this relationship is partly explained by adult drinking. METHODS: Alcohol Policy Scale (APS) scores that characterized the strength of the state-level alcohol policy environments were assessed with repeated cross-sectional Youth Risk Behavior Survey data of representative samples of high school students in grades 9 to 12, from biennial years between 1999 and 2011. RESULTS: In fully adjusted models, a 10 percentage point increase in APS scores (representing stronger policy environments) was associated with an 8% reduction in the odds of youth drinking and a 7% reduction in the odds of youth binge drinking. After we accounted for youth-oriented alcohol policies, the subgroup of population-oriented policies was independently associated with lower odds of youth drinking (adjusted odds ratio 0.94; 95% confidence interval 0.92-0.97) and youth binge drinking (adjusted odds ratio 0.96; 95% confidence interval 0.94-0.99). State-level per capita consumption mediated the relationship between population-oriented alcohol policies and binge drinking among youth. CONCLUSIONS: Stronger alcohol policies, including those that do not target youth specifically, are related to a reduced likelihood of youth alcohol consumption. These findings suggest that efforts to reduce youth drinking should incorporate population-based policies to reduce excessive drinking among adults as part of a comprehensive approach to preventing alcohol-related harms. Future research should examine influence of alcohol policy subgroups and discrete policies.


Assuntos
Consumo de Bebidas Alcoólicas/legislação & jurisprudência , Consumo Excessivo de Bebidas Alcoólicas/legislação & jurisprudência , Política Pública/legislação & jurisprudência , Assunção de Riscos , Estudantes/estatística & dados numéricos , Adolescente , Adulto , Consumo de Bebidas Alcoólicas/epidemiologia , Consumo de Bebidas Alcoólicas/prevenção & controle , Consumo Excessivo de Bebidas Alcoólicas/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Estados Unidos
7.
Addiction ; 110(3): 441-50, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25428795

RESUMO

AIMS: U.S. studies contribute heavily to the literature about the tax elasticity of demand for alcohol, and most U.S. studies have relied upon specific excise (volume-based) taxes for beer as a proxy for alcohol taxes. The purpose of this paper was to compare this conventional alcohol tax measure with more comprehensive tax measures (incorporating multiple tax and beverage types) in analyses of the relationship between alcohol taxes and adult binge drinking prevalence in U.S. states. DESIGN: Data on U.S. state excise, ad valorem and sales taxes from 2001 to 2010 were obtained from the Alcohol Policy Information System and other sources. For 510 state-year strata, we developed a series of weighted tax-per-drink measures that incorporated various combinations of tax and beverage types, and related these measures to state-level adult binge drinking prevalence data from the Behavioral Risk Factor Surveillance System surveys. FINDINGS: In analyses pooled across all years, models using the combined tax measure explained approximately 20% of state binge drinking prevalence, and documented more negative tax elasticity (-0.09, P = 0.02 versus -0.005, P = 0.63) and price elasticity (-1.40, P < 0.01 versus -0.76, P = 0.15) compared with models using only the volume-based tax. In analyses stratified by year, the R-squares for models using the beer combined tax measure were stable across the study period (P = 0.11), while the R-squares for models rely only on volume-based tax declined (P < 0.0). CONCLUSIONS: Compared with volume-based tax measures, combined tax measures (i.e. those incorporating volume-based tax and value-based taxes) yield substantial improvement in model fit and find more negative tax elasticity and price elasticity predicting adult binge drinking prevalence in U.S. states.


Assuntos
Bebidas Alcoólicas/economia , Consumo Excessivo de Bebidas Alcoólicas/epidemiologia , Comércio/estatística & dados numéricos , Impostos/estatística & dados numéricos , Adulto , Feminino , Humanos , Modelos Lineares , Masculino , Prevalência , Estados Unidos/epidemiologia , Adulto Jovem
8.
Int J Alcohol Drug Res ; 4(2): 119-130, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26925185

RESUMO

AIMS: To test the hypotheses that stronger policy environments are associated with less impaired driving and that driving-oriented and drinking-oriented policy subgroups are independently associated with impaired driving. DESIGN: State-level data on 29 policies in 50 states from 2001-2009 were used as lagged exposures in generalized linear regression models to predict self-reported impaired driving. SETTING: Fifty United States and Washington, D.C. PARTICIPANTS: A total of 1,292,245 adults (≥ 18 years old) biennially from 2002-2010. MEASURES: Alcohol Policy Scale scores representing the alcohol policy environment were created by summing policies weighted by their efficacy and degree of implementation by state-year. Past-30-day alcohol-impaired driving from 2002-2010 was obtained from the Behavioral Risk Factor Surveillance System surveys. FINDINGS: Higher Alcohol Policy Scale scores are strongly associated with lower state-level prevalence and individual-level risk of impaired driving. After accounting for driving-oriented policies, drinking-oriented policies had a robust independent association with reduced likelihood of impaired driving. Reduced binge drinking mediates the relationship between drinking-oriented policies and impaired driving, and driving-oriented policies reduce the likelihood of impaired driving among binge drinkers. CONCLUSIONS: Efforts to reduce alcohol-impaired driving should focus on reducing excessive drinking in addition to preventing driving among those who are impaired.

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