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1.
J Med Food ; 23(3): 224-232, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31928474

RESUMO

Childhood obesity is a medical condition of major public health concern. Chia seeds are used to treat certain noncommunicable diseases, and they are rich in omega-3 fatty acids, which contribute to the absorption of vitamins. A randomized double-blind clinical trial of 30 obese children was performed. The sample was composed of prepubertal 5- to 10-year-old children of both sexes with body mass indexes equal to or above the 95th percentile who were recruited through the Pediatric Department of the Faculdade de Medicina do ABC. Blood samples were drawn, the children were weighed and measured, and a 24-h dietary recall was obtained before and after the treatment. Not only were significant differences observed for fibrinogen (P = .011) but a correlation between the changes in markers and the presence of fibers was also observed for two inflammatory parameters: tumor necrosis factor-α (P = .027) and nuclear factor-κß (P = .059). These results indicate that chia seeds may have anti-inflammatory effects related to their fiber content in the context of childhood obesity.


Assuntos
Obesidade/dietoterapia , Sobrepeso/dietoterapia , Salvia/metabolismo , Criança , Pré-Escolar , Método Duplo-Cego , Feminino , Humanos , Masculino , NF-kappa B/genética , NF-kappa B/metabolismo , Obesidade/genética , Obesidade/metabolismo , Sobrepeso/genética , Sobrepeso/metabolismo , Salvia/química , Sementes/química , Sementes/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
2.
Anal Bioanal Chem ; 398(1): 265-94, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20521143

RESUMO

Mass spectrometry has recently undergone a second contemporary revolution with the introduction of a new group of desorption/ionization (DI) techniques known collectively as ambient mass spectrometry. Performed in an open atmosphere directly on samples in their natural environments or matrices, or by using auxiliary surfaces, ambient mass spectrometry (MS) has greatly simplified and increased the speed of MS analysis. Since its debut in 2004 there has been explosive growth in the applications and variants of ambient MS, and a very comprehensive set of techniques based on different desorption and ionization mechanisms is now available. Most types of molecules with a large range of masses and polarities can be ionized with great ease and simplicity with the outstanding combination of the speed, selectivity, and sensitivity of MS detection. This review describes and compares the basis of ionization and the concepts of the most promising ambient MS techniques known to date and illustrates, via typical analytical and bioanalytical applications, how ambient MS is helping to bring MS analysis deeper than ever into the "real world" open atmosphere environment--to wherever MS is needed.


Assuntos
Espectrometria de Massas/instrumentação , Espectrometria de Massas/métodos , Preparações Farmacêuticas/análise , Humanos
3.
Analyst ; 135(4): 738-44, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20349539

RESUMO

A fast and reliable method is presented for the analysis of vegetable oils. Easy ambient sonic-spray ionization mass spectrometry (EASI-MS) is shown to efficiently desorb and ionize the main oil constituents from an inert surface under ambient conditions and to provide comprehensive triacylglyceride (TAG) and free fatty acid (FFA) profiles detected mainly as either [TAG + Na](+) or [FFA-H](-) ions. EASI(+/-)-MS analysis is simple, easily implemented, requires just a tiny droplet of the oil and is performed without any pre-separation or chemical manipulation. It also causes no fragmentation of TAG ions hence diacylglyceride (DAG) and monoacylglyceride (MAG) profiles and contents can also be measured. The EASI(+/-)-MS profiles of TAG and FFA permit authentication and quality control and can be used, for instance, to access levels of adulteration, acidity, oxidation or hydrolysis of vegetable oils in general.


Assuntos
Ácidos Graxos/química , Óleos de Plantas/química , Espectrometria de Massas por Ionização por Electrospray/instrumentação , Triglicerídeos/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Ultrassom
4.
Molecules ; 12(3): 423-32, 2007 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-17851401

RESUMO

Aqueous extracts of green yerba maté (Ilex paraguariensis) and green tea (Camellia sinensis) are good sources of phenolic antioxidants, as already described in the literature. The subject of this study were organic extracts from yerba maté, both green and roasted, and from green tea. Their phenolic profiles were characterized by direct infusion electrospray insertion mass spectrometry (ESI-MS) and their free radical scavenging activity was determined by the DPPH assay. Organic extracts containing phenolic antioxidants might be used as natural antioxidants by the food industry, replacing the synthetic phenolic additives used nowadays. Ethanolic and aqueous extracts from green yerba maté, roasted yerba maté and green tea showed excellent DPPH scavenging activity (>89%). The ether extracts from green and roasted yerba maté displayed a weak scavenging activity, different from the behavior observed for the green tea ether extract. The main phenolic compounds identified in green yerba maté water and ethanolic extracts were: caffeic acid, quinic acid, caffeoyl glucose, caffeoylquinic acid, feruloylquinic acid, dicaffeoylquinic acid and rutin. After the roasting process two new compounds were formed: caffeoylshikimic acid and dicaffeoylshikimic acid. The ethanolic extracts from yerba maté, both roasted and green, with lower content of phenolic compounds (3.80 and 2.83 mg/mL) presented high antioxidant activity and even at very low phenolic concentrations, ether extract from GT (0.07 mg/mL) inhibited DPPH over 90%.


Assuntos
Antioxidantes/isolamento & purificação , Camellia sinensis/química , Ilex paraguariensis/química , Fenóis/isolamento & purificação , Espectrometria de Massas por Ionização por Electrospray , Sequestradores de Radicais Livres/metabolismo , Extratos Vegetais/química
5.
Lipids ; 41(8): 813-7, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17120936

RESUMO

The oil content, FA, and lipid class composition of the mature seeds of six Cordia species were analyzed. Mature seeds of each species were collected in their natural habitat from 2002 to 2004. The total lipid content varied from 1.9% to 13.2%, there being significant differences between the results found in different years for each species and between the species analyzed. The contents of FFA varied from 2.0% to 7.9% of total lipids. Neutral lipids (NL) were the largest class, making up between 89.6% and 96.4% of the total lipids; the phospholipids (PL) were the second largest class (3.0% to 8.9% of the total lipids), and the glycolipids (GL) were the smallest class (0.6 to 3.4%). The presence of GLA was determined in each class of lipids; it is predominant in the NL. Levels of GLA ranged from 1.2% to 6.8% of total seed FA. This is, to our knowledge the first study of lipid composition in seeds of species of Cordia from Brazil.


Assuntos
Cordia/metabolismo , Ácidos Graxos Ômega-6/metabolismo , Sementes/metabolismo , Brasil , Cordia/química , Ácidos Graxos Ômega-6/química , Sementes/química
6.
J Mass Spectrom ; 41(2): 185-90, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16382484

RESUMO

Samples of must derived from six different varieties of grapes taken during the fermentation process, as well as the respective wine samples directly after the end of the malolactic fermentation, were analyzed by direct infusion negative ion mode electrospray ionization mass spectrometry (ESI-MS). Diagnostic ions for must were different from those of wine samples, although small variations for each of the grape varieties were also detected. The addition of unfermented must or sugar to wine could also be clearly detected. The spectra were acquired in a few minutes per sample, indicating that ESI-MS can be used for high-throughput analysis of samples and should prove useful for quality control during and after the fermentation process.


Assuntos
Espectrometria de Massas por Ionização por Electrospray/métodos , Vitis/química , Vinho/análise , Especificidade da Espécie , Vitis/classificação , Volatilização
7.
Anal Chem ; 77(22): 7429-33, 2005 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-16285696

RESUMO

An improved approach for the direct infusion electrospray ionization mass spectrometry (ESI-MS) analysis of vegetable oils is described. The more polar components of the oils, including the fatty acids, are simply extracted with methanol/water (1:1) solution and analyzed by direct infusion ESI-MS in both the negative and positive ion modes. This fingerprinting analysis was applied to genuine samples of olive, soybean, corn, canola, sunflower, and cottonseed oil, to admixtures of these oils, and samples of aged soybean oil. ESI-MS fingerprints in the positive ion mode of the extracts divide the oils into well-defined groups, as confirmed by principal component analysis, whereas ESI-MS fingerprints in the negative ion mode clearly differentiate olive oil from the five other refined oils. The method is also shown to detect aging and adulteration of vegetable oils.


Assuntos
Óleos de Plantas/análise , Óleos de Plantas/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Óleos de Plantas/classificação , Fatores de Tempo
8.
Analyst ; 129(8): 739-44, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15284918

RESUMO

Crude ethanolic extracts of propolis, a natural resin, have been directly analysed using electrospray ionization mass (ESI-MS) and tandem mass spectrometry (ESI-MS/MS) in the negative ion mode. European, North American and African samples have been analyzed, but emphasis has been given to Brazilian propolis which displays diverse and region-dependent chemical composition. ESI-MS provides characteristic fingerprint mass spectra, with propolis samples being divided into well-defined groups directly related to their geographical origins. Chemometric multivariate analysis statistically demonstrates the reliability of the ESI-MS fingerprinting method for propolis. On-line ESI-MS/MS tandem mass spectrometry of characteristic [M - H](-) ion markers provides an additional dimension of fingerprinting selectivity, while structurally characterizing the ESI-MS marker components of propolis. By comparison with standards, eight such markers have been identified: para-coumaric acid, 3-methoxy-4-hydroxycinnamaldehyde, 2,2-dimethyl-6-carboxyethenyl-2H-1-benzopyran, 3-prenyl-4-hydroxycinnamic acid, chrysin, pinocembrin, 3,5-diprenyl-4-hydroxycinnamic acid and dicaffeoylquinic acid. The negative mode ESI-MS fingerprinting method is capable of discerning distinct composition patterns to typify, to screen the sample origin and to reveal characteristic details of the more polar and acidic chemical components of propolis samples from different regions of the world.

9.
Braz. j. microbiol ; 35(1/2): 104-109, Jan.-Jun. 2004. ilus
Artigo em Inglês | LILACS | ID: lil-388806

RESUMO

Própolis brasileira, proveniente do estado de São Paulo, foi submetida à extração usando vários solventes, resultando em extratos com diferentes composições. Estes extratos foram submetidos à Cromatografia em Camada Delgada (CCD). Análise bioautográfica das placas de CCD permitiu identificar as frações com atividade antimicrobiana, que foram então analisadas por Cromatografia Líquida de Alta Eficiência (CLAE). Ensaios in vitro freqüentemente utilizados para avaliar a atividade de própolis frente a bactérias Gram-positivas foram comparados para determinar qual renderia os resultados mais consistentes. A atividade bactericida destes extratos foi analisada por Diluição Seriada em Tubos e por testes de Difusão em Agar. O método de Diluição em Tubos permitiu obter os resultados mais consistentes e a Concentração Bactericida Mínima dos extratos variou entre 2,5 e 20,0 mg/mL, para as espécies de bactérias Gram-positivas testadas. Os resultados do método de Difusão em Agar foram diretamente proporcionais à hidrossolubilidade dos extratos, e não avaliaram a atividade bactericida corretamente. A atividade bactericida desta amostra resultou da combinação de vários componentes, identificados por CLAE, que foram extraídos preferencialmente usando etanol 50 per center como solvente.


Assuntos
Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Delgada , Técnicas In Vitro , Própole/análise , Métodos
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