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1.
Trauma Surg Acute Care Open ; 9(1): e001195, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38450048

RESUMEN

Objectives: Advanced Trauma Life Support (ATLS) focuses on care of injured patients in the first hour of resuscitation. Expanded demand for courses has led to a concurrent need for new instructors. Nurse practitioners and physician assistants (NPs/PAs) work on trauma services and duties include patient, staff, and outreach education. The goal of this project was to assess NP/PA self-reported knowledge and skills pertinent to ATLS and identify potential barriers to becoming instructors. Materials: This was a voluntary 91-question survey emailed to NP/PA lists obtained from professional societies and online social media channels. NPs/PAs completed a survey reflecting self-reported knowledge, experience, comfort level, and barriers to teaching ATLS interactive discussions and skills. Responses were recorded using a Likert scale and results were documented as percentages. Number of years of experience versus perceived knowledge and comfort teaching were compared using a χ2 test of independence. Results: There were 1696 completed surveys. Most NPs/PAs thought they had adequate knowledge and experience to teach interactive discussions and skills. Those with more years of experience and those who completed more ATLS courses had higher percentages. The number 1 barrier to teaching was lack of formal teaching experience followed by perceived hierarchy concerns. Experience and comfort with skills that fell below 50% were pediatric airway (49.5%), needle and surgical cricothyrotomy (49.8% and 44.8%), diagnostic peritoneal lavage (21.6%), and venous cutdown (20.8%). Conclusion: NPs/PAs with experience in trauma reported having the knowledge and skill to teach ATLS. A majority are comfortable teaching interactive discussions and skills for which they are knowledgeable. The primary barrier to teaching was lack of formal teaching experience, which is covered in the ATLS Instructor course. Training NPs/PAs to become instructors would increase the instructor base and allow for increased promulgation of ATLS and trauma education. Level of evidence: IV.

2.
Food Chem ; 340: 127906, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-32890857

RESUMEN

Wine quality and character are defined in part by the terroir in which the grapes are grown. Metabolomic techniques, such as nuclear magnetic resonance (NMR) spectroscopy and inductively coupled plasma mass spectrometry (ICP-MS), are used to characterise wines and to detect wine fraud in other countries but have not been extensively trialled in Australia. This paper describes the use of ICP-MS and NMR to characterise a selection of Pinot noir wines. Wines from varying terroirs could be somewhat distinguished by their mineral content using principal component analysis (PCA). PCA was able to separate wines by their Australian states more clearly than by region. Metabolomic analysis of the wines using NMR did not find any correlations with climate/daytime temperatures, or region. An analysis of coinertia suggested that the two datasets were not redundant, and it is proposed that ICP-MS data is the most useful for determining regionality.


Asunto(s)
Análisis de los Alimentos/métodos , Espectroscopía de Resonancia Magnética/métodos , Espectrometría de Masas/métodos , Vino/análisis , Australia , Clima , Análisis de los Alimentos/estadística & datos numéricos , Metabolómica , Nueva Zelanda , Análisis de Componente Principal , Temperatura , Vitis/química , Vitis/metabolismo
3.
Ann Anat ; 233: 151587, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32998029

RESUMEN

Animal studies are essential to biomedical research and the cornerstone is a reproducible animal model. While there are many reports on rodent peripheral nerve injury models, a large animal model is essential to confirm the effects of nerve regeneration over the longer distances of regeneration required in humans. Swine have long been used as a large animal model for other surgical and biomedical studies. This paper represents a novel neurovascular injury model in the Sus scrofa domesticus swine (American Yorkshire pig). This paper will describe our experience and recommendations with pre-operative, operative and post-operative protocols and our refinements to produce an effective model.


Asunto(s)
Arteria Femoral , Sus scrofa , Animales , Modelos Animales de Enfermedad , Arteria Femoral/cirugía , Isquemia , Regeneración Nerviosa , Nervio Ciático , Porcinos
4.
Molecules ; 25(4)2020 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-32085581

RESUMEN

Volatile phenols have been implicated as contributors to off-odors associated with taints from bushfire smoke and microbial spoilage. Various methods for the amelioration of off-odors have been evaluated, but to date, they have not included cyclodextrin (CD) polymers. In the current study, two CD polymers were prepared from ß- and γ-CD, using hexamethylene diisocyanate (HDI) as a crosslinking agent. Adsorption tests were performed with four volatile phenols (guaiacol, 4-methylguaiacol, 4-ethylguaiacol and 4-ethylphenol) at concentrations up to 1 mg/L. The removal of volatile phenols by CD polymers achieved equilibrium almost instantly, with isotherm tests suggesting an adsorption capacity of 20.7 µg of volatile phenol per gram of polymer. Langmuir and Freundlich models were subsequently used to fit the data. In batch adsorption tests, the CD polymers achieved 45 to 77% removal of volatile phenols. Polymer reusability was also evaluated and was found to be excellent. A comparison between volatile phenol adsorption by CDs vs. CD polymers, determined using a novel four-phase headspace solid-phase microextraction (HS-SPME) method for gas chromatography-mass spectrometry (GC-MS), suggests CD polymers offer several advantages for use by the wine industry.


Asunto(s)
Reactivos de Enlaces Cruzados/química , Ciclodextrinas/química , Fenoles/aislamiento & purificación , Polímeros/química , Vino/análisis , Adsorción , Espectroscopía de Protones por Resonancia Magnética , Temperatura , Volatilización
5.
Molecules ; 24(19)2019 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-31546625

RESUMEN

Volatile phenols exist in wine and can be markers for Brettanomyces and smoke taint off-odors. Cyclodextrins (CDs) are found to be capable of forming inclusion complexes with volatile phenols. Cross peaks on 2D 1H ROESY nuclear magnetic resonance (NMR) spectra demonstrated inclusion of volatile phenols in the ß-CD cavity, while difference tests confirmed this resulted in a perceptible reduction of their sensory impact. However, a conventional headspace solid phase microextraction (HS-SPME) method using an isotopically labelled normalizing standard failed to quantify the residual volatile phenols by gas chromatography-mass spectrometry (GC-MS) because of inclusion of the standard by the CDs. A new method involving an additional liquid phase was developed and validated for quantitation of volatile phenols in the presence of CDs. The retention of eight volatile phenols by α-, ß-, and γ-CD was subsequently studied.


Asunto(s)
Brettanomyces/química , Ciclodextrinas/química , Cromatografía de Gases y Espectrometría de Masas/métodos , Espectroscopía de Resonancia Magnética/métodos , Fenoles/química
6.
Molecules ; 23(5)2018 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-29748522

RESUMEN

3-Isobutyl-2-methoxypyrazine (IBMP), the most prevalent grape-derived methoxypyrazine, can contribute green bell pepper, vegetative and herbaceous aromas and flavours to wines. At elevated concentrations, this potent odorant may mask desirable fruity and floral aromas in wine and may be considered as a fault. A new remediation method for wines with elevated IBMP levels has been trialled using magnetic polymers, prepared in the same way as ordinary polymers but with the incorporation of iron oxide nanoparticles as magnetic substrates. Characterisation by Fourier transform-infrared (FTIR) spectroscopy and scanning electron microscopy (SEM) showed no difference between thermally synthesised and microwave synthesised polymers. Magnetic polymers were found to have removed over 40% of the IBMP present in spiked model wine and white wine within ten minutes. The addition of magnetic nanoparticles and microwave-induced polymerisation did not affect the adsorption properties of the polymer in model wine and the polymer could be regenerated at least five times. Both Langmuir and Freundlich isotherms were found to fit the data for both types of polymer. However, attempts to produce imprinted polymers were not achieved, as they were found not to be differentiated from non-imprinted counterparts via adsorption tests.


Asunto(s)
Magnetismo , Polímeros/química , Pirazinas/análisis , Vino/análisis , Adsorción , Cromatografía de Gases y Espectrometría de Masas , Cinética , Microextracción en Fase Sólida , Espectroscopía Infrarroja por Transformada de Fourier , Estadística como Asunto , Temperatura
7.
Comput Inform Nurs ; 35(10): 512-519, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28541965

RESUMEN

Increasing health portal participation actively engages patients in their care and improves outcomes. The primary aim for this project was to increase patient health portal utilization. Nurses used a tablet-based demo to teach patients how to navigate the health portal. Assigning health videos to the portal was a tactic used to increase utilization. Each patient participant was surveyed about health portal utilization at initial nurse navigator appointment, day of procedure, and 30 days after discharge. Seventy-three percent (n = 14) of the 19 selected patients received the intervention; 36% (n = 4) of patients reported using a health portal feature; meaningful use metric preintervention increased from 12% to 16% after the intervention; 16% and 18% of patients viewed assigned videos in their health portal prior to procedure and after hospital discharge. Patients need a reason to access their health portal. Education alone is not enough to motivate patient portal use. Further research is needed to specify what tactics are required to motivate patients to use their health portals.


Asunto(s)
Cardiopatías/psicología , Conducta en la Búsqueda de Información , Participación del Paciente/estadística & datos numéricos , Portales del Paciente/estadística & datos numéricos , Anciano , Registros Electrónicos de Salud/estadística & datos numéricos , Práctica Clínica Basada en la Evidencia/métodos , Femenino , Humanos , Internet/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Acceso de los Pacientes a los Registros/psicología , Acceso de los Pacientes a los Registros/normas , Participación del Paciente/psicología , Portales del Paciente/normas , Satisfacción del Paciente , Proyectos Piloto
8.
J Trauma Acute Care Surg ; 83(1): 190-196, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28328684

RESUMEN

Nurse practitioners and physician assistants, collectively known as advanced practitioners (APs), enhance the provision of care for the acutely injured patient. Despite their prevalence, institutions employ, train, and utilize these providers with significant variability. The Eastern Association for the Surgery of Trauma, the Society of Trauma Nurses, and the American Association of Surgical Physician Assistants acknowledge the value of APs and support their utilization in the management of injured and critically ill patients. This position paper offers insight into the history of, scope of practice for, and opportunities for optimal utilization of APs in trauma, critical care, and acute care surgery services.


Asunto(s)
Cuidados Críticos , Unidades de Cuidados Intensivos , Enfermeras Practicantes , Asistentes Médicos , Traumatología , Humanos , Grupo de Atención al Paciente , Estados Unidos , Recursos Humanos
9.
Nurs Adm Q ; 41(1): 11-19, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-27918400

RESUMEN

The healthcare provider landscape is rapidly changing. Given the imminent retirement of baby boomer physicians, implementation of the Affordable Care Act, and the increased utilization of health care services by an ever-aging population, the supply of providers cannot keep pace with the demand for services. This has led to an increased utilization of advanced clinical practitioners (ACPs). This article shows how one large highly-matrixed health care system approached identifying this workforce, and how thought leaders worked collaboratively with physicians, administrators, and ACPs to meet a growing demand for providers. Carolinas HealthCare System developed a 3-pronged approach to this opportunity. The development of a Center for Advanced Practice was explored and implemented. This Center serves as a 2-way conduit of information and ideas between system administrators and providers. It also serves as a central source of regulatory and practice information for administrators and providers. The growing number of open ACP positions, along with the reluctance to employ novice and new graduate ACPs, led to the development of a postgraduate transition to practice fellowship program. This program's clinical tracks and curriculum are described. Finally, a collaborative effort between the health care system and a local university resulted in the local offering of an acute care nurse practitioner program, which allowed system nurses to continue their education without the need for relocation. Higher satisfaction and engagement, lower turnover, better career opportunities, more satisfied administrators, and physicians all contributed to the overwhelming success of this initiative.


Asunto(s)
Atención a la Salud/métodos , Atención a la Salud/tendencias , Competencia Clínica/normas , Educación Continua/métodos , Becas/métodos , Humanos , Satisfacción en el Trabajo , Patient Protection and Affordable Care Act/tendencias , Selección de Personal/métodos , Selección de Personal/normas
10.
J Agric Food Chem ; 64(49): 9401-9411, 2016 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-27960298

RESUMEN

Synthesized p-coumaroyl and feruloyl l-tartrate esters were submitted to Brettanomyces bruxellensis strains AWRI 1499, AWRI 1608, and AWRI 1613 to assess their role as precursors to ethylphenols in wine. No evolution of ethylphenols was observed. Additionally, p-coumaroyl and feruloyl glucose were synthesized and submitted to B. bruxellensis AWRI 1499, which yielded both 4-ethylphenol and 4-ethylguaiacol. Unexpected chemical transformations of the hydroxycinnamoyl glucose esters during preparation were investigated to prevent these in subsequent synthetic attempts. Photoisomerization gave an isomeric mixture containing the trans-esters and undesired cis-esters, and acyl migration resulted in a mixture of the desired 1-O-ß-ester and two additional migrated forms, the 2-O-α- and 6-O-α-esters. Theoretical studies indicated that the photoisomerization was facilitated by deprotonation of the phenol, and acyl migration is favored during acidic, nonaqueous handling. Preliminary LC-MS/MS studies observed the migrated hydroxycinnamoyl glucose esters in wine and allowed for identification of feruloyl glucose in red wine for the first time.


Asunto(s)
Brettanomyces/metabolismo , Ésteres/metabolismo , Glucosa/metabolismo , Fenoles/metabolismo , Tartratos/metabolismo , Vino/análisis , Ésteres/química , Glucosa/química , Fenoles/química , Tartratos/química , Vino/microbiología
11.
J Agric Food Chem ; 63(37): 8241-6, 2015 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-26321591

RESUMEN

Menthiafolic acid (6-hydroxy-2,6-dimethylocta-2,7-dienoic acid, 2a) was quantified by GC-MS in 28 white wines, 4 Shiraz wines, and for the first time in 6 white grape juice samples. Menthiafolic acid was detected in all but one of the wine samples at concentrations ranging from 26 to 342 µg/L and in the juice samples from 16 to 236 µg/L. Various model fermentation experiments showed that some menthiafolic acid in wine could be generated from the grape-derived menthiafolic acid glucose ester (2b) during alcoholic and malolactic fermentation. Samples containing high concentrations of menthiafolic acid were also analyzed by enantioselective GC-MS and were shown to contain this compound in predominantly the (S)-configuration. Enantioselective analysis of wine lactone (1) in one of these samples, a four-year-old Chardonnay wine showed, for the first time, the presence of the 3R,3aR,7aS isomer of wine lactone (1b), which is the enantiomer of the form previously reported as the sole isomer present in young wine samples. The weakly odorous 3R,3aR,7aS 1b form comprised 69% of the total wine lactone in the sample. On the basis of the enantioselectivity of the hydrolytic conversion of menthiafolic acid to wine lactone at pH 3.0 determined previously and the relative proportions of (R)- and (S)-menthiafolic acid in the Chardonnay wine, the predicted ratio of wine lactone enantiomers that would be formed from hydrolysis at ambient temperature of the menthiafolic acid present in this wine was close to the ratio measured, which was consistent with menthiafolic acid being the major or sole precursor to wine lactone in this sample.


Asunto(s)
Caprilatos/análisis , Ácidos Grasos Insaturados/análisis , Lactonas/análisis , Vino/análisis , Bebidas/análisis , Fermentación , Frutas/química , Cromatografía de Gases y Espectrometría de Masas , Glucosa/metabolismo , Concentración de Iones de Hidrógeno , Odorantes/análisis , Saccharomyces cerevisiae/metabolismo , Estereoisomerismo , Vitis/química
12.
Sensors (Basel) ; 15(8): 19495-506, 2015 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-26266410

RESUMEN

This paper presents a multipurpose and low cost sensor for the simultaneous monitoring of temperature and ullage of wine in barrels in two of the most important stages of winemaking, that being fermentation and maturation. The distributed sensor subsystem is imbedded within the bung of the barrel and runs on battery for a period of at least 12 months and costs around $27 AUD for all parts. In addition, software was designed which allows for the remote transmission and easy visual interpretation of the data for the winemaker. Early warning signals can be sent when the temperature or ullage deviates from a winemakers expectations so remedial action can be taken, such as when topping is required or the movement of the barrels to a cooler cellar location. Such knowledge of a wine's properties or storage conditions allows for a more precise control of the final wine quality.


Asunto(s)
Temperatura , Vino/análisis , Tecnología Inalámbrica/instrumentación , Costos y Análisis de Costo , Fermentación , Internet , Propiedades de Superficie , Vino/economía , Tecnología Inalámbrica/economía
13.
J Agric Food Chem ; 63(8): 2137-44, 2015 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-25661455

RESUMEN

Preveraison treatment of Shiraz berries with either 1-naphthaleneacetic acid (NAA) or Ethrel delayed the onset of ripening and harvest. NAA was more effective than Ethrel, delaying harvest by 23 days, compared to 6 days for Ethrel. Sensory analysis of wines from NAA-treated fruit showed significant differences in 10 attributes, including higher "pepper" flavor and aroma compared to those of the control wines. A nontargeted analysis of headspace volatiles revealed modest differences between wines made from control and NAA- or Ethrel-treated berries. However, the concentration of rotundone, the metabolite responsible for the pepper character, was below the level of detection by solid phase microextraction-gas chromatography-mass spectrometry in control wines, low in Ethrel wines (2 ng/L), and much higher in NAA wines (29 ng/L). Thus, NAA, and to a lesser extent Ethrel, treatment of grapes during the preveraison period can delay ripening and enhance rotundone concentrations in Shiraz fruit, thereby enhancing wine "peppery" attributes.


Asunto(s)
Aromatizantes/química , Ácidos Naftalenoacéticos/farmacología , Reguladores del Crecimiento de las Plantas/farmacología , Vitis/química , Vino/análisis , Adulto , Femenino , Frutas/química , Frutas/efectos de los fármacos , Frutas/crecimiento & desarrollo , Cromatografía de Gases y Espectrometría de Masas , Humanos , Masculino , Persona de Mediana Edad , Estructura Molecular , Odorantes/análisis , Olfato , Gusto , Vitis/efectos de los fármacos , Vitis/crecimiento & desarrollo , Adulto Joven
14.
J Nat Prod ; 78(1): 131-45, 2015 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-25581486

RESUMEN

Two unstable hydroperoxides, 6b and 10a, and 13 downstream sesquiterpenoids have been isolated from the autoxidation mixture of the bicyclic sesquiterpene α-guaiene (1) on cellulose filter paper. One of the significant natural products isolated was rotundone (2), which is the only known impact odorant displaying a peppery aroma. Other products included corymbolone (4a) and its C-6 epimer 4b, the (2R)- and (2S)-rotundols (7a/b), and several hitherto unknown epimers of natural chabrolidione A, namely, 7-epi-chabrolidione A (3a) and 1,7-epi-chabrolidione A (3b). Two 4-hydroxyrotundones (8a/b) and a range of epoxides (9a/b and 5a/b) were also formed in significant amounts after autoxidation. Their structures were elucidated on the basis of spectroscopic data and X-ray crystallography, and a number of them were confirmed through total synthesis. The mechanisms of formation of the majority of the products may be accounted for by initial formation of the 2- and 4-hydroperoxyguaienes (6a/b and 10a/b) followed by various fragmentation or degradation pathways. Given that α-guaiene (1) is well known to exist in the essential oils of numerous plants, coupled with the fact that aerial oxidation to form this myriad of downstream oxidation products occurs readily at ambient temperature, suggests that many of them have been overlooked during previous isolation studies from natural sources.


Asunto(s)
Azulenos/química , Azulenos/aislamiento & purificación , Peróxido de Hidrógeno/aislamiento & purificación , Sesquiterpenos de Guayano/química , Sesquiterpenos de Guayano/aislamiento & purificación , Cristalografía por Rayos X , Peróxido de Hidrógeno/química , Estructura Molecular , Oxidación-Reducción , Sesquiterpenos/química , Sesquiterpenos/aislamiento & purificación , Estereoisomerismo
15.
J Agric Food Chem ; 63(7): 1932-8, 2015 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-25626924

RESUMEN

Deuterium-labeled guaiane derivatives and their precursors, namely, d5-2R-rotundol (11a), d5-2S-rotundol (11b), d5-bulnesone (14), d5-2R-bulnesol (16), d7-α-guaiene (10), and d7-α-bulnesene (15), were synthesized in good yields as GC-MS internal standards for comparing the behavior of α-guaiene (1) and α-bulnesene (5) under autoxidative conditions. It was found that approximately 99% of α-guaiene coated onto filter paper and exposed to air at ambient temperature was autoxidized after 48 h and up to 7% of rotundone (3) and 0.6% of rotundols (2a/b) were formed during this period. Autoxidation of α-bulnesene (5) was considerably slower, with approximately 80% remaining after 2 days and yielding less than 1.5% of α-bulnesone (7) and 0.3% and 0.9% of bulnesols 6a and 6b, respectively, after 5 days. The results indicate the feasibility of rapid changes of aroma profiles of herbs and other plant materials over time when exposed to air.


Asunto(s)
Azulenos/química , Aromatizantes/química , Sesquiterpenos de Guayano/química , Sesquiterpenos/química , Odorantes/análisis , Oxidación-Reducción
16.
J Agric Food Chem ; 63(4): 1242-1250, 2015 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-25582184

RESUMEN

Little attention has been paid to the color change or chemical compositional changes that occur in grape stems and how this correlates with the berry ripening process. Recently we have found that the change in grape peduncle color of Shiraz (Vitis vinifera) from green at veraison to predominantly brown at harvest occurs in parallel with berry ripening and as such may represent a new way of assisting in the prediction of grape maturity and harvest date. We have now investigated further the link between certain key chemical compositional changes that occur in the grape stem (peduncle and rachis) from veraison to harvest and how these attributes correlate with the observed color change in the vineyard. We report that peduncle moisture content has an excellent linear correlation with the color hue value and is negatively correlated in a strong fashion with the chlorophyll and carotenoid pigment ratio (Ca+b/Cx+c) within the peduncles. Significant differences in the moisture content, total chlorophylls (including chlorophyll a and b levels), total carotenoids, total phenolics, and the antioxidant capacity (DPPH) levels between the peduncles and rachises were found as they evolve from veraison to harvest. Finally, we have demonstrated for the first time that peduncle moisture content codevelops with the prototypical berry ripeness parameters (oBrix, pH, TA), which provides for the development of a new approach for viticulturists and winemakers to evaluate grape ripeness through peduncle moisture levels and therefore assist in harvest decision making.

17.
J Nat Prod ; 77(11): 2522-36, 2014 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-25330459

RESUMEN

The diastereomeric ratio of epoxidation of the internally bridged carbon-carbon double bond of guaiol (1a) is strongly influenced by the combined effects of the types of remote protecting groups on the hydroxyisopropyl side chain, choice of solvent, and epoxidizing reagent. This observation has allowed us to devise concise stereoselective syntheses of a range of guaiane-type sesquiterpenoids via an epoxidation, ring-opening/elimination, and functionality manipulation sequence. Natural products guaia-4(5)-en-11-ol (2a), guaia-5(6)-en-11-ol (3), and aciphyllene (4a) and epimers of the recently isolated natural products, 1-epi-guaia-4(5)-en-11-ol (2b), 1-epi-aciphyllene (4b), and 1-epi-melicodenones C (5a) and E (6a), were synthesized in good yields in relatively few steps.


Asunto(s)
Sesquiterpenos de Guayano/síntesis química , Sesquiterpenos/síntesis química , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Sesquiterpenos/química , Sesquiterpenos de Guayano/química , Estereoisomerismo
18.
J Agric Food Chem ; 62(44): 10809-15, 2014 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-25307830

RESUMEN

The aroma link between pepper and wine has recently been elucidated to be due to the important aroma compound rotundone. To date, rotundone is the only known impact odorant with a peppery aroma. Although the concentration found in products of natural origin is small, the odor detection threshold is among the lowest of any natural product yet discovered. We report herein the identification of the first known precursor to rotundone, namely, α-guaiene, and that one mechanism of transformation is simple aerial oxidation.


Asunto(s)
Azulenos/química , Piper nigrum/química , Extractos Vegetales/química , Sesquiterpenos de Guayano/química , Azulenos/síntesis química , Azulenos/aislamiento & purificación , Estructura Molecular , Odorantes/análisis , Oxidación-Reducción , Extractos Vegetales/síntesis química , Extractos Vegetales/aislamiento & purificación , Sesquiterpenos/química , Sesquiterpenos/aislamiento & purificación , Sesquiterpenos de Guayano/síntesis química , Sesquiterpenos de Guayano/aislamiento & purificación
19.
Acta Crystallogr Sect E Struct Rep Online ; 70(Pt 7): o758, 2014 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-25161551

RESUMEN

The title compound, C15H24O2 [systematic name: (4S,4aR,6R,8aR)-4a-hy-droxy-4,8a-dimethyl-6-(prop-1-en-2-yl)octahydro-naphthalen-1(2H)-one], features two edge-shared six-membered rings with the hydroxyl and methyl substituents at this bridge being trans. One adopts a flattened chair conformation with the C atoms bearing the carbonyl and methyl substituents lying 0.5227 (16) and 0.6621 (15) Å, respectively, above and below the mean plane through the remaining four C atoms (r.m.s. deviation = 0.0145 Å). The second ring, bearing the prop-1-en-2-yl group, has a chair conformation. Supra-molecular helical chains along the b axis are found in the crystal packing, which are sustained by hy-droxy-carbonyl O-H⋯O hydrogen bonding.

20.
Acta Crystallogr Sect E Struct Rep Online ; 70(Pt 7): o776-7, 2014 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-25161564

RESUMEN

Four independent mol-ecules (A-D) comprise the asymmetric unit of the title compound, C15H26O2, which differ only in the relative orientations of the terminal -C(Me)2OH groups [e.g. the range of Cmethyl-ene-Cmethine-Cquaternary-Ohy-droxy torsion angles is 52.7 (7)-57.1 (6)°, where the Cmethyl-ene atom is bound to an epoxide C atom]. The five-membered rings adopt envelope conformations, with the methyl-ene C atom adjacent to the methine C atom being the flap atom in each case. In each mol-ecule, the conformation of the seven-membered ring is a half-chair, with the Cmethyl-ene-Cmethine bond, flanked by methyl-ene C atoms, being the back of the chair. Supra-molecular helical chains along the b axis are found in the crystal packing, sustained by hy-droxy-epoxide O-H⋯O hydrogen bonding. Mol-ecules of A self-associate into a chain as do those of D. A third independent chain comprising B and C mol-ecules is also formed. The studied crystal is a pseudo-merohedral twin (minor component ca 21%).

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