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1.
N Engl J Med ; 382(8): 697-705, 2020 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-31860793

RESUMO

BACKGROUND: The causative agents for the current national outbreak of electronic-cigarette, or vaping, product use-associated lung injury (EVALI) have not been established. Detection of toxicants in bronchoalveolar-lavage (BAL) fluid from patients with EVALI can provide direct information on exposure within the lung. METHODS: BAL fluids were collected from 51 patients with EVALI in 16 states and from 99 healthy participants who were part of an ongoing study of smoking involving nonsmokers, exclusive users of e-cigarettes or vaping products, and exclusive cigarette smokers that was initiated in 2015. Using the BAL fluid, we performed isotope dilution mass spectrometry to measure several priority toxicants: vitamin E acetate, plant oils, medium-chain triglyceride oil, coconut oil, petroleum distillates, and diluent terpenes. RESULTS: State and local health departments assigned EVALI case status as confirmed for 25 patients and as probable for 26 patients. Vitamin E acetate was identified in BAL fluid obtained from 48 of 51 case patients (94%) in 16 states but not in such fluid obtained from the healthy comparator group. No other priority toxicants were found in BAL fluid from the case patients or the comparator group, except for coconut oil and limonene, which were found in 1 patient each. Among the case patients for whom laboratory or epidemiologic data were available, 47 of 50 (94%) had detectable tetrahydrocannabinol (THC) or its metabolites in BAL fluid or had reported vaping THC products in the 90 days before the onset of illness. Nicotine or its metabolites were detected in 30 of 47 of the case patients (64%). CONCLUSIONS: Vitamin E acetate was associated with EVALI in a convenience sample of 51 patients in 16 states across the United States. (Funded by the National Cancer Institute and others.).


Assuntos
Lesão Pulmonar Aguda/patologia , Líquido da Lavagem Broncoalveolar/química , Sistemas Eletrônicos de Liberação de Nicotina , Vaping/efeitos adversos , Vitamina E/análise , Lesão Pulmonar Aguda/etiologia , Adolescente , Adulto , Idoso , Fumar Cigarros , Óleo de Coco/análise , Feminino , Humanos , Limoneno/análise , Masculino , Pessoa de Meia-Idade , Estados Unidos , Adulto Jovem
2.
Molecules ; 24(18)2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31547401

RESUMO

Volatile compounds in flowers of Rhododendron delavayi, R. agastum, R. annae, and R. irroratum were analyzed using comprehensive two-dimensional gas chromatography-mass spectrometry (GC×GC) coupled with high-resolution quadrupole time-of-flight mass spectrometry (QTOFMS). A significantly increased number of compounds was separated by GC×GC compared to conventional one-dimensional GC (1DGC), allowing more comprehensive understanding of the volatile composition of Rhododendron flowers. In total, 129 volatile compounds were detected and quantified. Among them, hexanal, limonene, benzeneacetaldehyde, 2-nonen-1-ol, phenylethyl alcohol, citronellal, isopulegol, 3,5-dimethoxytoluene, and pyridine are the main compounds with different content levels in all flower samples. 1,2,3-trimethoxy-5-methyl-benzene exhibits significantly higher content in R. irroratum compared to in the other three species, while isopulegol is only found in R. irroratum and R. agastum.


Assuntos
Flores/química , Odorantes/análise , Rhododendron/química , Compostos Orgânicos Voláteis/análise , /análise , Aldeídos/análise , Cromatografia Gasosa , Cromatografia Gasosa-Espectrometria de Massas/métodos , Limoneno/análise , Espectrometria de Massas , Microextração em Fase Sólida , Especificidade da Espécie
3.
Analyst ; 144(14): 4153-4161, 2019 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-31144689

RESUMO

Breast cancer (BC), ranked as the fifth amongst all cancers, remains at the top of women's cancers worldwide followed by colorectal, lung, cervix, and stomach cancers. The main handicap of most of the screening/diagnostic methods is based on their low sensitivity and specificity and the invasive behavior of most sampling procedures. The aim of this study was to establish the volatomic pattern of BC and cancer-free (CF) tissues (n = 30) from the same patients, as a powerful tool to identify a set of volatile organic metabolite (VOM) potential BC biomarkers which might be used together or complement with the traditional BC diagnostics strategies, through the integration of chromatographic data, obtained by solid-phase microextraction followed by gas chromatography-mass spectrometry (SPME/GC-qMS), with chemometric tools. A total of four metabolites: limonene, decanoic acid, acetic acid and furfural presented the highest contribution towards discrimination of BC and CF tissues (VIP > 1, p < 0.05). The discrimination efficiency and accuracy of BC tissue metabolites was ascertained by ROC curve analysis that allowed the identification of some metabolites with high sensitivity and specificity. The results obtained with this approach suggest the possibility of identifying endogenous metabolites as a platform to find potential BC biomarkers and pave the way to investigate the related metabolomic pathways in order to improve BC diagnostic tools. Moreover, deeper investigations could unravel novel mechanistic insights into the disease pathophysiology.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/diagnóstico , Compostos Orgânicos Voláteis/análise , Ácido Acético/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Ácidos Decanoicos/análise , Feminino , Furaldeído/análise , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Limoneno/análise , Metabolômica/métodos , Pessoa de Meia-Idade , Análise Multivariada , Curva ROC
4.
Nutrients ; 11(4)2019 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-31010207

RESUMO

Microbial communities are responsible for the unique functional properties of chocolate. During microbial growth, several antimicrobial and antioxidant metabolites are produced and can influence human wellbeing. In the last decades, the use of starter cultures in cocoa fermentation has been pushed to improve nutritional value, quality, and the overall product safety. However, it must be noted that unpredictable changes in cocoa flavor have been reported between the different strains from the same species used as a starter, causing a loss of desirable notes and flavors. Thus, the importance of an accurate selection of the starter cultures based on the biogenic effect to complement and optimize chocolate quality has become a major interest for the chocolate industry. This paper aimed to review the microbial communities identified from spontaneous cocoa fermentations and focused on the yeast starter strains used in cocoa beans and their sensorial and flavor profile. The potential compounds that could have health-promoting benefits like limonene, benzaldehyde, 2-phenylethanol, 2-methylbutanal, phenylacetaldehyde, and 2-phenylethyl acetate were also evaluated as their presence remained constant after roasting. Further research is needed to highlight the future perspectives of microbial volatile compounds as biomarkers to warrant food quality and safety.


Assuntos
Anti-Infecciosos/análise , Antioxidantes/análise , Cacau/química , Chocolate/microbiologia , Fermentação , Alimento Funcional/análise , Compostos Orgânicos Voláteis/análise , Acetaldeído/análogos & derivados , Acetaldeído/análise , Acetaldeído/farmacologia , Acetatos/análise , Acetatos/farmacologia , Aldeídos/análise , Aldeídos/farmacologia , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Benzaldeídos/análise , Benzaldeídos/farmacologia , Culinária , Microbiologia de Alimentos , Humanos , Limoneno/análise , Limoneno/farmacologia , Álcool Feniletílico/análogos & derivados , Álcool Feniletílico/análise , Álcool Feniletílico/farmacologia , Paladar , Compostos Orgânicos Voláteis/farmacologia , Leveduras/crescimento & desenvolvimento , Leveduras/metabolismo
5.
Biomed Chromatogr ; 33(7): e4530, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30845345

RESUMO

The aim of the present study was to develop a method based on gas chromatography-tandem mass spectrometry (GC-MS/MS) to determine and quantify the d-limonene in mouse plasma and tissue samples. This new method was validated for the quantification of d-limonene with the linearity ranges 1.0-1000.0 ng/mL (r2 > 0.9952) for plasma samples and 5.0-5000.0 ng/g (r2 > 0.9940) for tissue samples. The intra- and inter-day assay of precisions in plasma and tissues were <13.4% and the accuracies were within 91.1-105.8%. In the oral/inhalation administration pharmacokinetics and tissue distribution studies, the main pharmacokinetic parameters were the peak concentration = (97.150 ± 34.450)/(4336.415 ± 1142.418) ng/mL, the area under the curve = (162.828± 27.447)/(2085.721 ± 547.787) h ng/mL and the half-life = (3.196 ± 0.825)/(0.989 ± 0.095) h. The tissue distribution of d-limonene in mice after oral/inhalation administration demonstrated a decreasing tendency in different tissues (liver > kidney > heart > lung > spleen).


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Limoneno , Espectrometria de Massas em Tandem/métodos , Administração por Inalação , Administração Oral , Animais , Feminino , Limite de Detecção , Limoneno/administração & dosagem , Limoneno/análise , Limoneno/farmacocinética , Modelos Lineares , Camundongos , Camundongos Endogâmicos C57BL , Reprodutibilidade dos Testes , Distribuição Tecidual
6.
Biomed Chromatogr ; 33(5): e4517, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30807652

RESUMO

Enantioseparation of limonene-based bicyclic 1,3-aminoalcohols and 1,3,5- and 1,3,6-aminodiols was performed by normal-phase high-performance liquid chromatographic and supercritical fluid chromatographic (SFC) methods on polysaccharide-based chiral stationary phases. The effects of the composition of the mobile phase, the column temperature and the structures of the analytes and chiral selectors on retention and selectivity were investigated by normal-phase LC and SFC technique. Thermodynamic parameters derived from selectivity-temperature-dependence studies were found to be dependent on the chromatographic method applied, the nature of the chiral selector and the structural details of the analytes. Enantiorecognition in most cases was enthalpically driven but an unusual temperature behavior was also observed: decreased retention times were accompanied by improved separation factors with increasing temperature, i.e. some entropically driven separations were also observed. The elution sequence was determined in all cases. The separation of the stereoisomers was optimized in both chromatographic modalities.


Assuntos
Amino Álcoois/análise , Amino Álcoois/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia com Fluido Supercrítico/métodos , Limoneno/análise , Limoneno/isolamento & purificação , Amino Álcoois/química , Limoneno/química , Polissacarídeos/química , Estereoisomerismo , Termodinâmica
7.
Food Chem ; 275: 730-738, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30724256

RESUMO

The objective of this study was to investigate the volatile compounds of the leaves of ten perilla accessions as well as to determine total polyphenols, antioxidant capacity. Essential oil (EOs) content ranged from 0.33 to 1.75 mL/100 g d.w. in PS3 and J1 respectively. In this study sixty-five compounds were identified by GC-MS and characterized with the predominance of perillaldehyde, perilla ketone, ß-dehydro-elsholtzia ketone, limonene, shisofuran, farnesene (Z, E, α), ß-caryophyllene, trans-shisool. The biogenesis and composition of EOs are probably attributed to several factors. JTD3 had a significantly higher polyphenol content as well as showed the highest antioxidant capacity, whereas a strong positive linear correlation was observed between them. PS1 and NP 606 produced the maximum biomass correspondingly, while a large glandular trichome density was recorded for J1. The results support that perilla is rich in natural compounds that could be developed as nutraceuticals and/or phytomedicine.


Assuntos
Antioxidantes/química , Cromatografia Gasosa-Espectrometria de Massas , Óleos Voláteis/química , Perilla frutescens/química , Polifenóis/análise , Limoneno/análise , Modelos Lineares , Monoterpenos/análise , Perilla frutescens/metabolismo , Sementes/química , Sementes/metabolismo
8.
Ecotoxicol Environ Saf ; 171: 863-870, 2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-30665103

RESUMO

In the present study, the essential oil (EO) of Hyptis suaveolens has been explored for the first time for its phytotoxic and cytotoxic activities. The phytotoxic activity was assessed against rice (Oryza sativa) and its major troublesome weed, Echinochloa crus-galli, under laboratory and screenhouse conditions. GC-MS analysis revealed EO to be monoterpenoid (~ 79% monoterpenes) in nature with α-phellandrene (22.8%), α-pinene (10.1%) and limonene (8.5%) as the major chemical constituents. The laboratory bioassay showed a complete growth inhibitory effect of EO (≥ 2 mg mL-1) towards the germination and seedling growth of E. crus-galli. However, the inhibitory effect on rice was much less (~40% inhibition). EO caused visible injury, reduction in chlorophyll content, cell viability and ultimately led to complete wilting of E. crus-galli plants. In addition, EO altered the cell division in the meristematic cells of Allium cepa as depicted by ~63% decrease in mitotic index. EO exposure induced several aberrations at chromosomal (c-mitosis, anaphase bridges, chromosomal breakage, vagrant chromosomes, and sticky chromosomes) and cytological level (cytoplasm destruction, peripheral nuclei, and bi-nucleate cells). The present study concludes that H. suaveolens EO possesses phytotoxic activity due to its mito-depressive activity, and could serve as a natural herbicide under sustainable agricultural practices.


Assuntos
Herbicidas , Hyptis/química , Óleos Voláteis/toxicidade , Óleos Vegetais/toxicidade , Divisão Celular , Aberrações Cromossômicas , Echinochloa/efeitos dos fármacos , Echinochloa/crescimento & desenvolvimento , Germinação/efeitos dos fármacos , Herbicidas/química , Herbicidas/toxicidade , Limoneno/análise , Monoterpenos/análise , Óleos Voláteis/química , Oryza/efeitos dos fármacos , Óleos Vegetais/química
9.
Planta Med ; 85(3): 185-194, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30440078

RESUMO

The growing demand and commercial value of black pepper (Piper nigrum) has resulted in considerable interest in developing suitable and cost-effective methods for chemical characterization and quality evaluation purposes. In the current study, an extensive set of oil samples (n = 23) that were extracted by steam distillation from black pepper seeds was investigated to compare the chemical profiles of samples originating from nine major producing countries, as well as to identify potential chemical markers for quality evaluation. The twenty-two most abundant volatile compounds, mainly terpenes, in these oils were determined by conventional GC/MS analysis. Principal component analysis with this set of data revealed distinct clusters for samples that originated from China and Malaysia. Relatively low concentrations of sabinene (< 0.2%) and high concentrations of 3-carene (10.9 - 21.1%) were observed in these samples, respectively, compared to oil samples from other countries. The enantiomeric distributions of key terpene markers, viz., ß-pinene, sabinene, limonene, and terpinen-4-ol, were determined by chiral GC/MS analysis. Interestingly, for these four monoterpenes, levo-isomers were found to be predominant, emphasizing the highly conserved enzymatic processes occurring in P. nigrum. Moreover, consistent enantiomeric ratios ((-) isomer/(+) isomer) of 92.2 ± 3.0% for ß-pinene, 94.8 ± 2.8% for sabinene, 60.7 ± 1.1% for limonene, and 78.3 ± 1.3% for terpinen-4-ol were observed, independent of geographical location. These results demonstrate the potential of using stereospecific compositions as chiral signatures for establishing the authenticity and quality of black pepper oil.


Assuntos
Piper nigrum/química , Óleos Vegetais/química , Terpenos/análise , Compostos Bicíclicos com Pontes/análise , Cromatografia Gasosa-Espectrometria de Massas , Limoneno/análise , Monoterpenos/análise , Óleos Vegetais/normas , Estereoisomerismo
10.
Environ Pollut ; 244: 966-970, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30469291

RESUMO

Asthma is a common chronic disease. Exposure to limonene is commonplace because it may be used in the manufacture of personal care products and household cleaners. We investigated the influence of limonene on asthma in a population-based sample of approximately 3000 Canadians. During the Canada Health Measures Survey, carried out between 2012 and 2013, participants were asked if they wheezed or had a diagnosis of asthma, and underwent spirometry and measurement of the fraction of exhaled nitric oxide (FeNO). These variables were tested for an association with limonene concentrations measured in their household air samples, using linear regression analysis A 100% increase in air limonene concentration was associated with an approximate 17% adjusted relative increase wheezing with an odds ratio of 1.17 (95%CI 1.16, 1.18). The percent change in FeNO for a 100% increase in limonene was twice as large for children, 2.89% (95% CI 1.88, 4.43) compared to adults, 1.44% (95%CI 1.16, 1.79). Among boys, the odds ratio was 1.50 (95%CI 1.48, 1.52) between a 100% increase in limonene and a diagnosis of asthma. This study provides evidence that household exposure to limonene may increase the prevalence of asthma in the general population.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Asma/epidemiologia , Monitoramento Ambiental/métodos , Limoneno/análise , Adulto , Testes Respiratórios , Canadá , Criança , Expiração , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Óxido Nítrico/análise , Prevalência , Espirometria
11.
Nat Prod Res ; 33(10): 1504-1508, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-29277112

RESUMO

The chemical profile of the essential oil of callus and cell suspension cultures derivatives from stem and root of Hypericum triquetrifolium were explored by ITEX/GC-MS. The major constituents for stem derivatives were undecane (78.44%) and 2,4,6-trimethyl-octane (9.74%) for fresh calli, 2,4-dimethyl-benzaldehyde (46.94%), 2,3-dimethyl-undecane (28.39%), 2,4-dimethyl-1-hexene (10.17%), 1,2-oxolinalool (3.64%) and limonene (3.55%) for dry calli and undecane (61.24%), octane, 2,4,6-trimethyl- (16.73%), nonane, 3-methyl-(3.74%), 2,5-diphenyl-benzoquinone (3.70%) and limonene (3.60%) for cell suspension. However, for root derivatives, the dominated components were: undecane (49.94%), eucalyptol (12.07%), limonene (9.98%), toluene (9.03%) and 3-methyl-nonane (4.29%) for fresh calli, 2,4-dimethyl-benzaldehyde (29.80%), 1,1-dimethylethyl-cyclohexane (14.99%), 3-methyl-pentanal (14.99%), undecane (10.04%), beta-terpinyl acetate (8.60%), 1,2-oxolinalool (6.27%) and 2-pentyl-furan (4.09%) for dry calli, undecane (52.38%), 2,4,6-trimethyl-octane (13.81%), 3-methyl-nonane (5.73%), toluene (4.82%) and limonene (4.57%) for cell suspension derivative in root. The attained outcomes indicated that the alkane, aldehyde and monoterpene fractions dominated the chemical composition of essential oils.


Assuntos
Hypericum/química , Óleos Voláteis/análise , Óleos Voláteis/química , Alcanos/análise , Eucaliptol/análise , Cromatografia Gasosa-Espectrometria de Massas , Hypericum/citologia , Limoneno/análise , Monoterpenos/análise , Monoterpenos/química , Raízes de Plantas/química , Caules de Planta/química , Terpenos/análise , Técnicas de Cultura de Tecidos
12.
Crit Rev Food Sci Nutr ; 59(4): 611-625, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-28956626

RESUMO

Citrus EOs is an economic, eco-friendly and natural alternatives to chemical preservatives and other synthetic antioxidants, such as sodium nitrites, nitrates or benzoates, commonly utilized in food preservation. Citrus based EOs is obtained mainly from the peels of citrus fruits which are largely discarded as wastes and cause environmental problems. The extraction of citrus oils from the waste peels not only saves environment but can be used in various applications including food preservation. The present article presents elaborated viewpoints on the nature and chemical composition of different EOs present in main citrus varieties widely grown across the globe; extraction, characterization and authentication techniques/methods of the citrus EOs; and reviews the recent advances in the application of citrus EOs for the preservation of fruits, vegetables, meat, fish and processed food stuffs. The probable reaction mechanism of the EOs based thin films formation with biodegradable polymers is presented. Other formulation, viz., EOs microencapsulation incorporating biodegradable polymers, nanoemulsion coatings, spray applications and antibacterial action mechanism of the active compounds present in the EOs have been elaborated. Extensive research is required on overcoming the challenges regarding allergies and obtaining safer dosage limits. Shift towards greener technologies indicate optimistic future towards safer utilization of citrus based EOs in food preservation.


Assuntos
Citrus/química , Conservação de Alimentos/métodos , Frutas/química , Óleos Voláteis/isolamento & purificação , Antioxidantes/análise , Quitosana/química , Indústria Farmacêutica/métodos , Emulsões/química , Indústria Alimentícia/métodos , Embalagem de Alimentos/instrumentação , Conservantes de Alimentos , Gelatina/química , Limoneno/análise , Nanotecnologia , Óleos Voláteis/química , Polímeros/química , Terpenos/análise
13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 37(1): 306-11, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30221908

RESUMO

A comparative study of Cannabis sativa (Hemp) essential constituents obtained by using Supercritical Fluid Extraction (SCFE), Steam Distillation (SD) and Hydrodistillation (HD) is presented here. The optimized extraction temperatures were 130,110 and 50 ℃ for hydrodistillation, steam distillation and supercritical fluid extraction respectively. The essential oil of C. sativa was analyzed by using Gas chromatography mass spectrometry (GC-MS). A total of 33, 30 and 31 components have been identified in HD, SD and SCFE respectively. Yield of essential oil using SCFE (0.039%) was more than HD (0.025%) and SD (0.035%) extraction respectively. The main component of sesquiterpenes obtained by hydrodistillation at 130 ℃ with their percentages included caryophyllene (40.58%), trans-α-bergamotene (5.41%), humulene (10.97%), cis-ß-farnesene (8.53%) and monoterpenes included α-pinene (2.13%), d-limonene (6.46%), p-cymol (0.65%) and cineole (2.58%) respectively. The main component of sesquiterpenes obtained by SD steam distillation at 110 ℃ including caryophyllene (38.60%) trans-α-bergamotene (4.22%), humulene (10.26%), cis-ß-farnesene (6.67%) and monoterpenes included α-pinene (3.21%), d-limonene (7.07%), p-cymol (2.59%) and cineole (3.88%) whereas the more percentages of major components were obtained by SCFE at 50 ℃ included caryophyllene (44.31%), trans-α-bergamotene (6.79%), humulene (11.97%) cis-ß-farnesene (9.71%) and monoterpenes included α-pinene (0.45%), d-limonene (2.13%) p-cymol (0.19%) and cineole (1.38 %) respectively. We found yield/efficiency, chemical composition, quality of the essential oils by supercritical fluid extraction superior in terms of modern, green, saving energy and a rapid approach as compared to traditional techniques.


Assuntos
Cannabis/química , Óleos Voláteis/química , Cromatografia com Fluido Supercrítico , Destilação , Cromatografia Gasosa-Espectrometria de Massas , Limoneno/análise , Monoterpenos/análise
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