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1.
Forensic Sci Int ; 306: 110063, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31790891

RESUMO

Diagnosis of carbon monoxide (CO) poisonings has always been a challenging task due to the susceptibility to alterations of the optical state and degradation of blood samples during sampling, transport and storage, which highly affects the analysis with spectrophotometric methods. Methodological improvements are then required urgently because of increased reports of cases with discrepancies between results of the measured biomarker carboxyhemoglobin (COHb) and reported symptoms. Total blood CO (TBCO) measured chromatographically was thus proposed in a previous study as alternative biomarker to COHb. This approach was investigated in this study by comparing the two biomarkers and assessing the effects of various storage parameters (temperature, preservative, time, tube headspace (HS) volume, initial saturation level, freeze- and thaw- and reopening-cycles) over a period of one month. Results show that while for TBCO, concentrations are relatively stable over the observation period regardless of parameters such as temperature, time and HS volume, for COHb, concentrations are altered significantly during storage. Therefore, the use of TBCO as alternative biomarker for CO poisonings has been proposed, since it provides more valid results and is more stable even under non-optimal storage conditions. Additionally, it can be used to predict COHb in cases where sample degradation hinders optical measurement. Furthermore, a correction formula for COHb and TBCO is provided to be used in laboratories or circumstances where optimal storage or analysis is not possible, to obtain more accurate results.


Assuntos
Intoxicação por Monóxido de Carbono/diagnóstico , Monóxido de Carbono/sangue , Carboxihemoglobina/análise , Medicina Legal/métodos , Biomarcadores/sangue , Cromatografia Gasosa , Interpretação Estatística de Dados , Humanos , Oximetria , Manejo de Espécimes , Espectrofotometria
2.
J Chem Ecol ; 46(1): 1-9, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31840210

RESUMO

The rice stalk stink bug, Tibraca limbativentris, is an important rice pest in Brazil with a high invasive potential for Mexico and the USA. The sex pheromone of this species was previously identified as a combination of two stereoisomers of 1,10-bisaboladien-3-ol (zingiberenol), but the absolute configurations of these sesquiterpenes were not determined, neither were their effect(s) on T. limbativentris behavior evaluated. In this study, using two chiral columns, we compared retention times of the two natural 1,10-bisaboladien-3-ol stereoisomers from air-entrainment samples of male T. limbativentris with those of synthetic stereoisomers of 1,10-bisaboladien-3-ol. The results showed that T. limbativentris males produce (3S,6S,7R)-1,10-bisaboladien-3-ol (1) and (3R,6S,7R)-1,10-bisaboladien-3-ol (5) as their sex pheromone. Two new minor, male-specific components were also identified as cis and trans isomers of 2,10-bisaboladien-1-ol (sesquipiperitol). Y-tube olfactometer bioassays showed that the major (3S,6S,7R) isomer 1 was essential for attraction of T. limbativentris females, but the minor (3R,6S,7R) isomer 2 was not, nor did it show synergistic/antagonistic effects when added to the major isomer. The (1S,6S,7R) and (1R,6S,7R) stereoisomers of sesquipepiritol also attracted T. limbativentris females.


Assuntos
Comportamento Animal/efeitos dos fármacos , Heterópteros/química , Sesquiterpenos/análise , Atrativos Sexuais/farmacologia , Animais , Cromatografia Gasosa , Feminino , Heterópteros/metabolismo , Masculino , Sesquiterpenos/farmacologia , Atrativos Sexuais/análise , Estereoisomerismo , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/química
3.
J Forensic Sci ; 65(1): 170-182, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31211877

RESUMO

Forty-three fatalities involving the potent synthetic cannabinoid, 5-Fluoro-ADB, are summarized. For each case, a description of the terminal event, autopsy findings, cause of death, qualitative identification of 5-Fluoro-ADB and its ester hydrolysis metabolite, 5-Fluoro-ADB metabolite 7, in urine, and the quantitative values obtained in the blood specimens are outlined. Central blood concentrations ranged from 0.010 to 2.2 ng/mL for 5-Fluoro-ADB and 2.0 to 166 ng/mL for 5-Fluoro-ADB metabolite 7. Peripheral blood concentrations ranged from 0.010 to 0.77 ng/mL and 2.0 to 110 ng/mL for 5-Fluoro-ADB and 5-Fluoro-ADB metabolite 7, respectively. The majority of cases resulted in central to peripheral blood concentration ratios greater than 1 for 5-Fluoro-ADB (58%) and 5-Fluoro-ADB metabolite 7 (71%) suggesting that postmortem redistribution occurs to some extent. Combining the increased cardiac weight and/or gastric volume and toxicology data identifying 5-Fluoro-ADB, it is hypothesized that abuse of this substance may precipitate a dysrhythmia and cause sudden death.


Assuntos
/sangue , Indazóis/sangue , Indazóis/urina , Abuso de Maconha/mortalidade , Adulto , Cromatografia Gasosa , Cromatografia Líquida , Técnica de Imunoensaio Enzimático de Multiplicação , Ensaio de Imunoadsorção Enzimática , Toxicologia Forense , Humanos , Indazóis/efeitos adversos , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade , Estrutura Molecular , Miocárdio/patologia , Tamanho do Órgão , Estômago/patologia
4.
Food Chem ; 303: 125405, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31466029

RESUMO

The study aimed at evaluating the influence of fermented sugarcane molasses ageing on lees and the distillation process used for the production of rums. Molasses were freshly fermented or 3-months lees aged. Batch (PS: Pot Still) or continuous (CS: Coffey Still) distillation was carried out resulting in four different rum distillates. Gas chromatography and 3D-fluorescence enabled to differentiate rum distillates chemical composition according to the distillation process, regardless of the ageing on lees of fermented molasses. Differences in fluorescent PARAFAC components and volatile acids, acetals and carbonyls contents revealed the predominance of the physicochemical processes driven at the liquid-vapor interface of fermented molasses, generated by the distillation systems. Notwithstanding the distilling conditions, the long chain fatty ester content was significantly higher in the 3-months lees aged condition. Multivariate analysis highlighted that CS rum distillates were chemically more homogeneous than those obtained by PS that preserved the lees effect.


Assuntos
Bebidas Alcoólicas/análise , Destilação/métodos , Manipulação de Alimentos/métodos , Melaço/análise , Saccharum/química , Cromatografia Gasosa , Fermentação , Fatores de Tempo
5.
Food Chem ; 309: 125752, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31670128

RESUMO

In this work, a novel class of eight low viscosity hydrophobic deep eutectic solvents (DESs) has been designed and prepared from two kinds of quaternary ammonium salts and six kinds of water-insoluble fatty alcohols/acids. Several physical properties of these DESs, such as melting point, density and viscosity, have been determined to investigate their adaptability as solvents. Then, such DESs are used as extraction solvents in a vortex-assisted liquid-liquid microextraction for the extraction and preconcentration of phthalate esters (PEs) from water samples, and the content of PEs from food-contacted plastics is then determined by using gas chromatography. It is found that the analytic method developed in this work exhibits wide linear range of 5-1000 µg L-1, and the limit of detections for target analytes is as low as 1 µg L-1. Finally, the proposed method has been successfully used for the determination of PEs from food-contacted plastics.


Assuntos
Cromatografia Gasosa , Microextração em Fase Líquida/métodos , Ácidos Ftálicos/análise , Plásticos/química , Ésteres/química , Embalagem de Alimentos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Limite de Detecção , Ácidos Ftálicos/isolamento & purificação , Reprodutibilidade dos Testes , Solventes/química
6.
Food Chem ; 307: 125521, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31655264

RESUMO

The essential oils and antioxidant activity of four Thymus species were evaluated under five light spectra (namely, red, blue, red-blue, white, and greenhouse condition). The highest essential oil yield (4.17%) was observed under red light in T. migricus, while the lowest (1.05%) was observed in T. carmanicus under greenhouse conditions. Light quality also led to difference in essential oil constituents. The highest thymol (66%) was found in T. migricus exposed to blue light, while the least (1.69%) was observed in T. kotschyanus grown under red-blue light. The LED treatments did not induce any significant effect on carvacrol of Thymus species in comparison to the greenhouse condition. Finally, the analysis of variance indicates that the effect of light varied with the studied species. T. migricus performed the highest antioxidant capacity (IC50 = 176.8 µg/mL) under blue light. Overall, essential oil components as well as antioxidants showed significant responses to light emitting diodes wavelengths.


Assuntos
Antioxidantes/metabolismo , Luz , Timol/metabolismo , Thymus (Planta)/química , Análise de Variância , Antioxidantes/química , Cromatografia Gasosa , Análise por Conglomerados , Efeito Estufa , Óleos Voláteis/química , Análise de Componente Principal , Timol/química , Thymus (Planta)/crescimento & desenvolvimento , Thymus (Planta)/metabolismo
7.
Food Chem ; 306: 125623, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31606633

RESUMO

In this study, apple juice was fermented using Hanseniaspora osmophila X25-5 in pure culture as well as mixed culture with Torulaspora quercuum X24-4, which was inoculated simultaneously or sequentially. H. osmophila inhibited the growth of T. quercuum, while T. quercuum had little effect on the growth of H. osmophila. The simultaneous fermentation consumed relatively more sugar and resulted in the highest ethanol content. The production of organic acids varied depending on the yeast species employed and inoculation modality. Esters and alcohols were the main volatile families produced during fermentation, while ethyl esters and terpenes contributed most to the temperate fruity aroma. Gas chromatography-olfactometry (GC-O) showed that 3-methyl-1-butanol, ethyl 2-methylbutanoate, phenylethyl alcohol, ß-phenethyl acetate, and ß-damascenone were the most potent odorants in all samples. This study suggested that simultaneous fermentation with H. osmophila and T. quercuum might represent a novel strategy for the future production of cider.


Assuntos
Acetatos/análise , Fermentação , Hanseniaspora/metabolismo , Malus/metabolismo , Odorantes/análise , Torulaspora/metabolismo , Bebidas Alcoólicas , Cromatografia Gasosa , Ésteres/análise , Frutas/química , Norisoprenoides/análise , Olfatometria , Vinho/análise
8.
Food Chem ; 305: 125480, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31522125

RESUMO

Milk samples from 1264 cows in 85 farms were authenticated for different farming-systems using a 10-fold cross-validated linear-discriminant-analysis using Fourier-transform infrared spectra (FTIRS) and gas-chromatographic fatty-acid (FA) profiles. FTIRS gave correct classification greater than FAs (97.4% vs. 81.1%) during calibration, but slightly worse in validation (73.5% vs 77.3%) and their combination improved the results. All milk samples were processed into ripened model-cheeses, and analyzed by near-infrared-spectrometry (NIRS), by proton-transfer-reaction time-of-flight mass-spectrometry for their volatile organic compound (VOCs) fingerprint and by panel sensory profiling (SENS). Farming-system authentication on cheese samples was less efficient than on milk, but still possible. The instrumental methods yielded similar validation results, better than SENS, and their combination improved the correct classification rate. The efficiency of the different technics was affected by specific farming systems. In conclusion, dairy products could be discriminated for farming-systems with acceptable accuracy, but the methods tested differ in sampling procedure, rapidity and costs.


Assuntos
Queijo/análise , Ácidos Graxos/química , Aromatizantes/análise , Leite/química , Animais , Bovinos , Cromatografia Gasosa , Análise Discriminante , Ácidos Graxos/análise , Feminino , Análise de Alimentos , Espectrometria de Massas , Espectroscopia de Infravermelho com Transformada de Fourier , Compostos Orgânicos Voláteis/análise
9.
Biosci Biotechnol Biochem ; 84(1): 25-30, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31516064

RESUMO

The Japanese orange fly, Bactrocera tsuneonis, infests various citrus crops. While male pheromone components accumulated in the rectal glands are well characterized for Bactrocera, but information regarding the chemical factors involved in the life cycles of B. tsuneonis remains scarce. Herein, several volatile chemicals including a γ-decalactone, (3R,4R)-3-hydroxy-4-decanolide [(3R,4R)-HD], were identified as major components, along with acetamide and spiroketals as minor components in the rectal gland complexes of male B. tsuneonis flies. The lactone (3R,4R)-HD was also identified in female rectal gland complexes. The amount of this compound in mature males was significantly higher than those observed in females and immature males. The lactone (3R,4R)-HD was detected in flies fed with sucrose only, indicating that this lactone is not derived from dietary sources during adulthood, but biosynthesized in vivo. The predominant accumulation of (3R,4R)-HD in mature males also suggests a possible role in reproductive behavior.


Assuntos
Lactonas/química , Glândula de Sal/química , Tephritidae/fisiologia , Acetamidas/síntese química , Acetamidas/química , Animais , Cromatografia Gasosa , Citrus , Dieta , Feminino , Furanos/síntese química , Furanos/química , Japão , Lactonas/síntese química , Masculino , Espectrometria de Massas , Reprodução/fisiologia , Atrativos Sexuais/química , Comportamento Sexual Animal/fisiologia , Compostos de Espiro/síntese química , Compostos de Espiro/química , Sacarose
10.
Food Chem ; 307: 125534, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31644980

RESUMO

There has been increasing recent concern about the agricultural use of organophosphorus pesticides. A rapid and sensitive fluorescence assay for the detection of three organophosphorus pesticides has therefore been developed using 6-carboxy-fluorescein labeling aptamer as the probe and functionalized magnetic nanoparticles as the separation carrier. The aptamer hybridized with complementary DNA conjugated on the surface of the magnetic nanoparticles to form a magnetic aptamer-complementary DNA complex. Upon introducing the target organophosphorus pesticide, the aptamer departed from the complementary DNA, resulting in the fluorescence signal. Under optimized conditions, the limits of detection (LODs, S/N = 3) for trichlorfon, glyphosate, and malathion were 72.20 ng L-1, 88.80 ng L-1, and 195.37 ng L-1, respectively. The method was applied for the detection of trichlorfon, glyphosate, and malathion in spiked lettuce and carrot samples. The recoveries were in the range of 79.4%-118.7%, which were in good agreement with those obtained by gas chromatography, and the relative standard deviations were also acceptable. The method therefore has high sensitivity, so provides a means for the detection of multiple organophosphorus pesticides.


Assuntos
Aptâmeros de Nucleotídeos/química , Nanopartículas , Compostos Organofosforados/análise , Praguicidas/análise , Espectrometria de Fluorescência , Cromatografia Gasosa , Daucus carota/química , Corantes Fluorescentes , Glicina/análogos & derivados , Glicina/análise , Alface/química , Limite de Detecção , Magnetismo , Malation/análise , Praguicidas/química , Triclorfon/análise
11.
J Chem Ecol ; 46(1): 21-29, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31853815

RESUMO

Female Helicoverpa armigera emit a pheromone, comprised of a 98:2 ratio of (Z)-11-hexadecenal to (Z)-9-hexadecenal, to attract males. It has been proposed that "immature" female H. armigera modulate attraction of males by emitting an antagonist, (Z)-11-hexadecenol, along with pheromone during the first two nights of calling. However, it is unclear why females would call and simultaneously release pheromone and an antagonist. We conducted observations of female calling during the first five nights after adult emergence to determine periodicity. We also measured the relative abundance of (Z)-11-hexadecenol to the major component, (Z)-11-hexadecenal, on the surface of the gland of calling females and compared it to the ratio of these two compounds inside the gland over the first three nights after adult emergence to determine how much antagonist may be released. We found that young females (< 1-d-old) are unlikely to call and, based on the relative proportion of (Z)-11-hexadecenol on the gland surface, even if they did call would be unlikely to release sufficient (Z)-11-hexadecenol to diminish male attraction.


Assuntos
Fertilidade/fisiologia , Mariposas/fisiologia , Atrativos Sexuais/química , Aldeídos/análise , Aldeídos/isolamento & purificação , Aldeídos/farmacologia , Animais , Cromatografia Gasosa , Feminino , Masculino , Atrativos Sexuais/análise , Atrativos Sexuais/farmacologia , Comportamento Sexual Animal/efeitos dos fármacos , Microextração em Fase Sólida , Estereoisomerismo
12.
Artigo em Inglês | MEDLINE | ID: mdl-31677523

RESUMO

Fipronil is a broad-spectrum insecticide belonging to the phenylpyrazole chemical family, classified by the U.S. EPA as a group C (possible human) carcinogen. It is highly toxic to crustaceans, insects and zooplankton as well as to termites, rabbits and certain groups of gallinaceous birds. In European Union and Greece, fipronil is authorized only for the control of termites and cockroaches and not as a plant protection product or as a veterinary drug. The definition of residue of fipronil comprises of the sum of fipronil and its sulfone metabolite expressed as fipronil and is set at 5 µg kg-1. In this study, a sensitive and reliable modified QuEChERS method, proposed by the European Reference Laboratory for animal origin products, has been validated and applied to the residue analysis of fipronil and its metabolites (sulfone and desulfinyl) in chicken eggs and other egg products by LC-MS/MS and GC-ECD analysis. The two analytical systems performed almost equally concerning validation process and with regard to the analysis of real samples, results from both systems were in agreement: out of 11 samples analysed, 4 samples showed measurable residues of fipronil sulfone with 3 samples exceeding the MRL limit.


Assuntos
Cromatografia Gasosa/métodos , Ovos/análise , Inseticidas/análise , Pirazóis/análise , Espectrometria de Massas em Tandem/métodos , Animais , Galinhas , Cromatografia Líquida de Alta Pressão/métodos , Inseticidas/metabolismo , Limite de Detecção , Pirazóis/metabolismo
13.
Artigo em Inglês | MEDLINE | ID: mdl-31706183

RESUMO

The reported methods for the estimation of CG are indirect, long and tedious uses solvent extraction which results in lower recoveries due to several co-eluted components. The present study aims to develop and validate a high throughput method for the analysis of cyanogenic glycosides (CG) in flaxseed using extractive silylation. The experimental procedure comprised of preparation of trimethylsilyl (TMS) derivatives of CG, their quantitation through gas chromatography with flame ionization detector (GC-FID) and further characterization by LC-MS/MS. Different validation parameters determined in the experiment include the relative standard deviation both inter-day and intraday less than 5%, recovery in the range of 79.9-112.7%, limit of detection 4.72-6.43 µg/mL and limit of quantitation 14.31-19.50 µg/mL. Combinations of silylation reagent were screened in a central composite experimental design in order to examine their effect on the extraction recovery. Finally, the developed method was applied successfully to quantify CG in various flaxseed cultivars. Advantages of the extractive silylation are simple preparation, short reaction times and the combination of extraction and silylation in one step which indicate that the method has the potential to sensitively and accurately determine CG where large numbers of samples are being routinely analysed.


Assuntos
Cromatografia Gasosa/métodos , Linho/química , Glicosídeos/análise , Silanos/química , Cromatografia Líquida/métodos , Glicosídeos/química , Glicosídeos/isolamento & purificação , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodos
14.
Klin Lab Diagn ; 64(11): 644-648, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31747490

RESUMO

The aim of the study was to assess the information content of volatile fatty acid parameters for the differential diagnosis of infected and sterile pancreatic necrosis. The work is based on the results of examination and treatment of 34 patients with pancreatic necrosis. The analysis of concentrations of volatile fatty acids: acetic, propionic, butyric and isovaleric was carried out on an automated gas chromatograph «Crystallux-4000¼ with a capillary column «HP-FFAP¼ and flame ionization detector. The indicators of acetic, propionic, butyric, isovaleric acid and the sum of volatile fatty acids are statistically significantly higher in patients with infected pancreatic necrosis compared with the indicators of volatile fatty acids in patients with sterile pancreatic necrosis. Volatile fatty acid values can be used for the differential diagnosis of infected and sterile pancreatic necrosis.


Assuntos
Ácidos Graxos Voláteis/análise , Necrose/diagnóstico , Pâncreas/patologia , Cromatografia Gasosa , Diagnóstico Diferencial , Humanos
15.
Zhongguo Zhong Yao Za Zhi ; 44(15): 3287-3296, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31602885

RESUMO

To evaluate the pesticide residue risk of Jinyinhua Formula Granules( made from Lonicerae Japonicae Flos) used in the market preliminarily,20 samples of Jinyinhua Formula Granules from 5 manufactures were collected randomly through the national evaluative sampling test program. Totally 262 pesticides( involving 270 chemical monomers) with monitoring significance to traditional Chinese medicinal materials were detected. Samples were extracted by high speed homogenate with acetonitrile as solvent. And their residues were analyzed by GC-MS/MS and LC-MS/MS in MRM mode. No less than 2 groups of characteristic ion pairs were adopted for qualitative detection,and the calibration curve method was used for quantitative detection. The results showed that 20 pesticides were detected in 20 batches of Jinyinhua Formula Granules,with an average of about 9 pesticides detected in every batch,but no restricted pesticide was detected. The detected pesticides were all at the trace level,which was far lower than the limit of the general food standard. Therefore,the safety risk was low in Jinyinhua Formula Granules. In this study,a screening method for pesticide residues in Jinyinhua Formula Granules was established for the first time. The method was accurate and rapid,and the detection indicators were highly targeted. The results could provide theoretical reference for the prevention and control of pesticide safety risks in Jinyinhua Formula Granules and even traditional Chinese medicine formula granules.


Assuntos
Contaminação de Medicamentos , Medicamentos de Ervas Chinesas/análise , Resíduos de Praguicidas/análise , Cromatografia Gasosa , Cromatografia Líquida , Controle de Qualidade , Espectrometria de Massas em Tandem
16.
Environ Pollut ; 255(Pt 2): 112967, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31610516

RESUMO

A correct description of the concentration and distribution of particle bound polycyclic aromatic hydrocarbons is important for risk assessment of atmospheric particulate matter. A new targeted GC-MS/MS method was developed for analyzing 64 PAHs including compounds with a molecular weight >300, as well as nitro-, methyl-, oxy- and hydroxyl derivatives in a single analysis. The instrumental LOD ranged between 0.03 and 0.7 pg/µL for PAHs, 0.2-7.9 pg/µL for hydroxyl and oxy PAHs, 0.1-7.4 pg/µL for nitro PAHs and 0.06-0.3 pg/µL for methyl-PAHs. As an example for the relevance of this method samples of PM10 were collected at six sampling sites in Medellin, Colombia, extracted and the concentration of 64 compounds was determined. The 16 PAHs from the EPA priority list contributed only from 54% to 69% to the sum of all analyzed compounds, PAH with high molecular weight accounted for 8.8%-18.9%. Benzo(a)pyrene equivalents (BaPeq) were calculated for the estimation of the life time cancer (LCR). The LCR according to the samples ranged from 2.75 × 10-5 to 1.4 × 10-4 by a calculation with toxic equivalent factors (TEF) and 5.7 × 10-5 to 3.8 × 10-4 with potency equivalent factor (PEF). By using the new relative potency factors (RPF) recommended by US Environmental Protection Agency (U.S.EPA) the LCR ranged from 1.3 × 10-4 to 7.2 × 10-4. Hence, it was around six times higher than the well-known TEF. The novel method enables the reliable quantification of a more comprehensive set of PAHs bound on PM and thus will facilitate and improve the risk assessment of them.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Hidrocarbonetos Policíclicos Aromáticos/análise , Benzo(a)pireno/análise , Cromatografia Gasosa , Colômbia , Cromatografia Gasosa-Espectrometria de Massas , Material Particulado/análise , Medição de Risco , Espectrometria de Massas em Tandem
17.
J Agric Food Chem ; 67(41): 11444-11453, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31592644

RESUMO

Innovative approaches to develop flavors with high sensory appeal are critical in encouraging increased consumer preference and adoption of low sodium foods. Gas chromatography-olfactometry, coupled with stable isotope dilution assays and sensory experiments, led to the identification of the odorants responsible for an enhancement in saltiness perception of chicken broth prepared with thermally treated enzymatically hydrolyzed mushroom protein and cysteine, then reacted under kitchen-like cooking conditions. Comparative aroma extract dilution analysis revealed 36 odorants with flavor dilution factors between a range of 1 and 256. Sixteen odorants were quantitated and odor activity values (OAVs) calculated. Important odorants included 2-furfurylthiol (coffee, OAV 610), 1-(2-furyl)ethanethiol (meaty, OAV 78), 3-sulfanylpentan-2-one (catty, OAV 42), sotolon (maple, OAV 20), indole (animal, OAV 8), 2-methyl-3-(methyldithio)furan (meaty, OAV 3), and p-cresol (barnyard, OAV 1). An odor simulation model was evaluated in two consumer sensory studies. These studies confirmed that the addition of the aroma model increased the perceived saltiness of low sodium chicken broth (p < 0.05).


Assuntos
Agaricus/química , Cisteína/química , Proteínas Fúngicas/química , Odorantes/análise , Percepção Gustatória , Agaricus/metabolismo , Cloretos/análise , Cloretos/metabolismo , Cromatografia Gasosa , Culinária , Cisteína/metabolismo , Proteínas Fúngicas/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Temperatura Alta , Humanos , Hidrólise , Olfatometria , Olfato , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/metabolismo
18.
Medicine (Baltimore) ; 98(39): e16976, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31574796

RESUMO

RATIONALE: Halitosis is an unpleasant odor that emanates from the mouth. Studies show halitosis returns in a week, after treatment with PDT. Probably, bacteria living in the periodontal sulcus could recolonize the dorsum of the tongue. Until nowadays, there are no study in adult population that associates halitosis and periodontal treatment with follow-up evaluation. The aim of this randomized, controlled, single-blinded clinical trial is to treat oral halitosis in healthy adults with photodynamic therapy (PDT), associated with periodontal treatment and follow them up for 3 months. PATIENT CONCERNS:: the concerns assessments will be done over the study using anamnesis interviews and specific questionnaire. DIAGNOSES:: halitosis will be evaluated by OralChroma. INTERVENTIONS: The participants (n = 40) with halitosis will be randomized into 2 groups: G1-treatment with PDT (n = 20) or G2-cleaning of the tongue with a tongue scraper (n = 20). OUTCOMES: Halitosis will be evaluated by measuring volatile sulfur compounds using gas chromatography. After the treatments, a second evaluation will be performed, along with a microbiological analysis (RT-PCR) for the identification of the bacteria T. denticola. The assessment of halitosis and the microbiological analysis will be repeated. After that, patients will receive periodontal treatment. The participants will return after 1 week and 3 months for an additional evaluation. Quality of life will be measured by Oral Health Impact Profile questionnaire (OHIP-14). LESSONS: This protocol will determine the effectiveness of phototherapy regarding the reduction of halitosis in adults. clinicaltrials.gov NCT03996915. ETHICS AND DISSEMINATION: This protocol received approval from the Human Research Ethics Committee of Universidade Nove de Julho (certificate number: 3.257.104). The data will be published in a peer-reviewed periodical.


Assuntos
Halitose/tratamento farmacológico , Doenças Periodontais/terapia , Fotoquimioterapia , Cromatografia Gasosa , Seguimentos , Halitose/etiologia , Halitose/microbiologia , Humanos , Pessoa de Meia-Idade , Higiene Bucal , Doenças Periodontais/complicações , Doenças Periodontais/microbiologia , Fármacos Fotossensibilizantes/uso terapêutico , Recidiva , Método Simples-Cego , Resultado do Tratamento , Treponema denticola/isolamento & purificação
19.
J Food Sci ; 84(10): 2831-2839, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31573691

RESUMO

This study aims to investigate alterations in volatile compounds and chemical components that may affect the sensory properties of Cynanchi wilfordii roasted at 120 °C and 180 °C for various durations of time (0 to 4 min). For volatile compound profiles, tridecane, tetradecane, and ethyl hexyl ether were detected as major compounds of the sample without roasting. As the roasting temperature increased, the types of volatile compounds increased, whereas the content decreased with an increase in heterocyclic compound generation. The sample roasted at 120 °C for 1 min showed a notably different profile pattern from the other roasted samples. For the sniffing test performed by trained panelists using gas chromatography olfactometry, naphthalene and nonanal, which induce spicy and raw C. wilfordii, respectively, were perceived most intensely throughout all the samples. In the electronic tongue analysis, the sample roasting at 180 °C showed an increased and decreased pattern in umami taste and saltiness, respectively, with increased roasting time. Electronic tongue analysis results showed that the sample roasted at 180 °C for 4 min would have the best sensory preference. Along with the volatile compound profiles, the sample roasted at 120 °C for 1 min had more sourness than the other samples, and would potentially have distinctive sensory characteristics. This study should provide baseline data on variations in the sensory properties and industrial applications of C. wilfordii upon roasting. PRACTICAL APPLICATION: Various applications of food ingredients through changes in sensory characteristics by roasting will provide consumers more options for food selections. Accordingly, this study will be utilized by (1) individuals and food companies who are interested in functional foods, (2) individuals and food industries that seek optimum roasting conditions for proper sensory characteristics of foods, and (3) farmers and crop producers who seek for utilization the applications of Cynanchi wilfordii as a food ingredient.


Assuntos
Cynanchum/química , Aromatizantes/química , Compostos Orgânicos Voláteis/química , Cromatografia Gasosa , Culinária , Nariz Eletrônico , Temperatura Alta , Humanos , Paladar
20.
Environ Sci Pollut Res Int ; 26(32): 33341-33350, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31520391

RESUMO

The aim of this study was to compare environmental pollution and ecological states of two different areas of the Songhua River areas: near Harbin City and Tongjiang City, located at a distance of about 500 km downstream. The anthropogenic pollution concentrations of heavy metals (HM) were determined. The results showed that concentrations of eight metals (Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) in the water were in the range of 0.001-0.588 mg/L for Tongjiang and 0.001-0.508 mg/L for Harbin, while that in sediments were in the range of 0.67-1575.37 mg/kg for Tongjiang and 0.07-5617.13 mg/kg for Harbin, respectively. Bivalves from tested sites exposed to environmental pollution exhibited significantly different physiological states. The latter was assessed using the method of physiological loading, based on measuring the recovery time (Trec) of heart rate (HR) after removal of the load. Trec in mussels from Harbin was recorded in the range of 151 to 234 min, while that from Tongjiang was only 115 min. Cd, Cu, Pb, and Zn in mollusk soft tissues were also determined for Harbin and Tongjiang, respectively. The metal pollution index (MPI) and bioconcentration factor (BCF) in the mollusks were calculated for each metal. BCF in the mussels from the Tongjiang area was lower than that from the Harbin area. Physiological testing, as well as the concentration of HM in water, and sediment, and also the bioaccumulation of HM in tissue showed that the ecological state of the Tongjiang area was better than that of Harbin. Apparently, after more extensive studies, a methodological approach of assessing the ecological state of water areas, based on physiological state testing of aboriginal mollusks, could be used in the monitoring of pollution effects in water bodies and streams.


Assuntos
Biomarcadores Ambientais , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Animais , Bivalves , China , Cromatografia Gasosa , Ecologia , Sedimentos Geológicos/análise , Metais Pesados/análise , Medição de Risco , Rios/química
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