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1.
J Pharm Biomed Anal ; 189: 113424, 2020 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-32619729

RESUMEN

Frontotemporal dementia (FTD) is a neurodegenerative disorder characterized by progressive impairment in behavior, executive function, and language. The behavioral variant (bvFTD) is the most clinical common form and requires differential diagnosis with atypical Alzheimer's disease (AD) cases. This study aimed to investigate the plasma metabolite profile of patients with bvFTD compared to AD patients and cognitively healthy individuals using gas chromatography coupled to mass spectrometry (GCMS). This study included nine patients with bvFTD, 17 with AD and 15 cognitively healthy controls (training set), whose data were validated on a testing set (eight bvFTD, 14 AD and ten controls). The metabolites were detected by GCMS. A tendency towards a reduction in the levels of palmitoleic, oleic and lauric acids was found in the bvFTD group compared to the AD group; however, no significance after multiple comparison correction was observed. However, bvFTD group showed reduced levels of creatinine, glycine, tryptophan, uric acid, hypoxanthine, serine, valine, threonine, isoleucine, homoserine, methionine, glutamic acid, capric acid, tartronic acid, fumaric acid, and myo-inositol, metabolites related to glycine/serine/threonine, alanine/aspartate/glutamate pathways and aminoacyl-tRNA biosynthesis, when compared to controls. The data suggest that bvFTD patients may present an impairment of amino acid metabolism and the translation process. This pioneering study on bvFTD and its plasma metabolomic signature can be useful to provide new ideas about pathophysiological mechanisms, as well as guide more robust studies in search of possible biomarkers for the diagnosis of this important dementia.


Asunto(s)
Enfermedad de Alzheimer , Demencia Frontotemporal , Diagnóstico Diferencial , Demencia Frontotemporal/diagnóstico , Cromatografía de Gases y Espectrometría de Masas , Humanos , Pruebas Neuropsicológicas
2.
Food Chem ; 273: 144-150, 2019 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-30292360

RESUMEN

This work developed an analytical method to differentiate conventional and omega-3 fat acids enriched eggs by Raman spectroscopy and multivariate supervised classification with Partial Least Squares Discriminant Analysis (PLS-DA). Forty samples of enriched eggs and forty samples of different types of common eggs from different batches were used to build the model. Firstly, gas chromatography was employed to analyze fatty acid profiles in egg samples. Raman spectra of the yolk extracts were recorded in the range from 3100 to 990 cm-1. PLS-DA model was able to correctly classify samples with nearly 100% success rate. This model was validated estimating appropriate figures of merit. Predictions uncertainties were also estimated by bootstrap resampling. The most discriminant Raman modes were identified based on VIP (variables importance in projection) scores. This method has potential to assist food industries and regulatory agencies for food quality control, allowing detecting frauds and enabling faster and reliable analyzes.


Asunto(s)
Huevos/análisis , Ácidos Grasos Omega-3/análisis , Análisis de los Alimentos/métodos , Espectrometría Raman/métodos , Cromatografía de Gases , Análisis Discriminante , Yema de Huevo/química , Calidad de los Alimentos , Análisis de los Mínimos Cuadrados
3.
R. Inst. Adolfo Lutz ; 75: 01-11, 2016. tab, graf
Artículo en Inglés | VETINDEX | ID: vti-379239

RESUMEN

The frying by immersion is a widely used cooking process and it improves the food texture and flavor. This study analyzed the initial thermal oxidation in five edible vegetable oils used for frying. Oils samples were heated twice for 30 minutes, at 180 C and then at 240 C simulating the domestic stoves temperatures. The oils decomposition temperatures were determined by TG, being all of them > 250 C. The FA profile was analyzed by GC-FID and a slight decrease of UFA was found in corn and soybean oils. In canola, olive and sunflower oils, UFA was stable after heating treatment. Minor FA decomposition was found in canola oil, and followed by corn, olive, sunflower and soybean oils. NIR spectroscopy analyzes resulted in an extensive bands overlapping. The spectra were modeled by PCA and the oils were classified into two groups: fresh oil and heated oil, mainly by differing in 1900 nm region, associated with the carboxyl signal decrease, which might be related to the initial FA degradation in samples. It could partially understand what occurs to the vegetable oil in the beginning of its thermo-decomposition. These information are useful to consumers, food industry and health surveillance agency.(AU)


A fritura por imersão é um processo de cocção utilizado pela inclusão de textura e sabor aos alimentos. Foi analisada a oxidação térmica inicial de cinco óleos vegetais comestíveis utilizados para fritura de imersão. Amostras de óleos foram aquecidas duas vezes por 30 minutos, a 180 ºC e depois a 240 ºC, simulando-se as temperaturas de fogões domésticos. As temperaturas de decomposição dos óleos foram determinadas por TG, sendo > 250 ºC. O perfil de FA foi analisado por GC-FID, detectando-se pequeno decréscimo dos UFA nos óleos de milho e soja. Nos óleos de canola, oliva e girassol, os UFA foram estáveis após o tratamento térmico. A menor decomposição dos FA foi detectado no óleo de canola, seguido de milho, oliva, soja e girassol. Análises por espectroscopia NIR resultaram em grande sobreposição das bandas. Os espectros foram modelados por PCA, classificando-se os óleos em dois grupos: óleo fresco e óleo aquecido, principalmente pelas diferenças na região de 1900 nm, relacionadas ao decréscimo do sinal de carboxilas, e associadas à degradação inicial dos FA nas amostras. Ainda que parcialmente, pode-se entender o que ocorre com os óleos vegetais no início de termo-decomposição, abrangências que são úteis para consumidores, indústria alimentícia e órgão de vigilância sanitária.(AU)


Asunto(s)
Brassica napus/química , Aceite de Maíz/química , Aceite de Oliva/química , Aceite de Soja/química , Helianthus/química , Tratamiento Térmico , Calor , Ácidos Grasos/química , Aceites de Plantas/química
4.
Rev. Inst. Adolfo Lutz (Online) ; 75: 01-11, 2016. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1489532

RESUMEN

The frying by immersion is a widely used cooking process and it improves the food texture and flavor. This study analyzed the initial thermal oxidation in five edible vegetable oils used for frying. Oils samples were heated twice for 30 minutes, at 180 C and then at 240 C simulating the domestic stoves temperatures. The oils decomposition temperatures were determined by TG, being all of them > 250 C. The FA profile was analyzed by GC-FID and a slight decrease of UFA was found in corn and soybean oils. In canola, olive and sunflower oils, UFA was stable after heating treatment. Minor FA decomposition was found in canola oil, and followed by corn, olive, sunflower and soybean oils. NIR spectroscopy analyzes resulted in an extensive bands overlapping. The spectra were modeled by PCA and the oils were classified into two groups: fresh oil and heated oil, mainly by differing in 1900 nm region, associated with the carboxyl signal decrease, which might be related to the initial FA degradation in samples. It could partially understand what occurs to the vegetable oil in the beginning of its thermo-decomposition. These information are useful to consumers, food industry and health surveillance agency.


A fritura por imersão é um processo de cocção utilizado pela inclusão de textura e sabor aos alimentos. Foi analisada a oxidação térmica inicial de cinco óleos vegetais comestíveis utilizados para fritura de imersão. Amostras de óleos foram aquecidas duas vezes por 30 minutos, a 180 ºC e depois a 240 ºC, simulando-se as temperaturas de fogões domésticos. As temperaturas de decomposição dos óleos foram determinadas por TG, sendo > 250 ºC. O perfil de FA foi analisado por GC-FID, detectando-se pequeno decréscimo dos UFA nos óleos de milho e soja. Nos óleos de canola, oliva e girassol, os UFA foram estáveis após o tratamento térmico. A menor decomposição dos FA foi detectado no óleo de canola, seguido de milho, oliva, soja e girassol. Análises por espectroscopia NIR resultaram em grande sobreposição das bandas. Os espectros foram modelados por PCA, classificando-se os óleos em dois grupos: óleo fresco e óleo aquecido, principalmente pelas diferenças na região de 1900 nm, relacionadas ao decréscimo do sinal de carboxilas, e associadas à degradação inicial dos FA nas amostras. Ainda que parcialmente, pode-se entender o que ocorre com os óleos vegetais no início de termo-decomposição, abrangências que são úteis para consumidores, indústria alimentícia e órgão de vigilância sanitária.


Asunto(s)
Aceite de Oliva/química , Brassica napus/química , Helianthus/química , Calor , Tratamiento Térmico , Aceite de Maíz/química , Aceite de Soja/química , Ácidos Grasos/química , Aceites de Plantas/química
5.
Rev. Inst. Adolfo Lutz (Online) ; 75: 1/11-11/11, 2016. graf, tab, ilus
Artículo en Inglés | LILACS, Sec. Est. Saúde SP, SESSP-CTDPROD, Sec. Est. Saúde SP, SESSP-ACVSES, SESSP-IALPROD, Sec. Est. Saúde SP, SESSP-IALACERVO | ID: biblio-835637

RESUMEN

The frying by immersion is a widely used cooking process and it improves the food texture and flavor. This study analyzed the initial thermal oxidation in five edible vegetable oils used forfrying. Oils samples were heated twice for 30 minutes, at 180 °C and then at 240 °C simulating the domestic stoves temperatures. The oils decomposition temperatures were determined byTG, being all of them > 250 °C. The FA profile was analyzed by GC-FID and a slight decrease of UFA was found in corn and soybean oils. In canola, olive and sunflower oils, UFA was stableafter heating treatment. Minor FA decomposition was found in canola oil, and followed by corn, olive, sunflower and soybean oils. NIR spectroscopy analyzes resulted in an extensive bands overlapping. The spectra were modeled by PCA and the oils were classified into two groups: fresh oil and heated oil, mainly by differing in 1900 nm region, associated with the carboxyl signal decrease, which might be related to the initial FA degradation in samples. It could partiallyunderstand what occurs to the vegetable oil in the beginning of its thermo-decomposition. These information are useful to consumers, food industry and health surveillance agency.


A fritura por imersão é um processo de cozimento amplamente utilizado e melhora a textura e o sabor do alimento. Este estudo analisou a oxidação térmica inicial em cinco óleos vegetais comestíveis usados ​​para fritar. As amostras de óleo foram aquecidas duas vezes durante 30 minutos, a 180 ° C e depois a 240 ° C simulando as temperaturas dos fogões domésticos. As temperaturas de decomposição dos óleos foram determinadas por TG, sendo todas elas> 250 ° C. O perfil de FA foi analisado por GC-FID e uma ligeira diminuição de UFA foi encontrada em óleos de milho e de soja. Nos óleos de canola, azeite e girassol, a UFA foi estável após o tratamento térmico. A decomposição menor de FA foi encontrada em óleo de canola, seguido de óleo de milho, azeite, girassol e soja. As análises de espectroscopia NIR resultaram em uma ampla faixa de sobreposição. Os espectros foram modelados por PCA e os óleos foram classificados em dois grupos: óleo fresco e óleo aquecido, principalmente por diferença na região de 1900 nm, associado à diminuição do sinal carboxílico, o que pode estar relacionado à degradação inicial de FA nas amostras. Poderia entender parcialmente o que ocorre ao óleo vegetal no início de sua termo-decomposição. Essas informações são úteis para consumidores, indústria de alimentos e agência de vigilância da saúde.


Asunto(s)
Monitoreo del Ambiente , Tratamiento Térmico , Ácidos Grasos , Aceite de Maíz , Aceite de Soja , Aceites de Plantas
6.
Molecules ; 19(9): 14094-113, 2014 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-25207715

RESUMEN

A review taking into account the literature reports covering 20 years of fatty acid analysis by capillary electrophoresis is presented. This paper describes the evolution of fatty acid analysis using different CE modes such as capillary zone electrophoresis, non-aqueous capillary electrophoresis, micellar electrokinetic capillary chromatography and microemulsion electrokinetic chromatography employing different detection systems, such as ultraviolet-visible, capacitively coupled contactless conductivity, laser-induced fluorescence and mass spectrometry. In summary, the present review signals that CE seems to be an interesting analytical separation technique that is very useful for screening analysis or quantification of the usual fatty acids present in different matrices, offering short analysis times and a simple sample preparation step as inherent advantages in comparison with the classical methodology, making it a separation technique that is very attractive for quality control in industry and government agencies.


Asunto(s)
Ácidos Grasos/análisis , Electroforesis Capilar , Terminología como Asunto
7.
Anal Sci ; 27(5): 541, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21558663

RESUMEN

Qualitative differentiation between natural and enriched chicken eggs through omega (ω) 3 fatty acid profiles by capillary zone electrophoresis (CZE) under direct UV detection at 200 nm is proposed. The electrolyte background consisted of 12.0 mmol L(-1) tetraborate buffer (pH 9.2) mixed with 12.0 mmol L(-1) Brij 35, 17% acetonitrile (ACN) and 33% methanol (MeOH). Omega 3 fatty acid profile in chicken egg samples were analyzed by CZE system and confirmed by single-quadrupole mass spectrometry with an electrospray ionization probe set to negative ionization mode after sample preparation by the Folch method. The results showed that ω fatty acid profiles analyzed by the CZE approach can be used to chemical markers to monitor fraud, presenting simplicity, short analysis time (10 min) and low cost as advantages.


Asunto(s)
Huevos/análisis , Ácidos Grasos Omega-3/análisis , Animales , Pollos , Electroforesis Capilar , Estructura Molecular , Espectrofotometría Ultravioleta
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