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1.
Artigo em Inglês | MEDLINE | ID: mdl-31596187

RESUMO

Fatty acid esters of 3-monochloropropanediol (3-MCPD), 2-monochlorpropanediol (2-MCPD), and glycidol are process-induced chemical contaminants found in refined vegetable oils. Due to their toxicological properties, there is potential concern regarding exposure to these compounds, particularly for formula-fed infants where refined edible oils are the primary fat source in commercial infant formulas. In order to assess exposure, 55 commercial oil samples, specifically intended for use in infant formula, were collected in 2015 from various infant formula manufacturers in the United States and analysed using a LC-MS/MS direct detection method. At the time of collection, there were no validated methods for the analysis of MCPD and glycidyl esters in infant formula. Therefore, analysis of these commercial oil samples served as an alternative for confirming the presence of these ester contaminants in infant formula. Bound 3-MCPD and glycidol concentrations in these oils ranged from below the limit of quantitation (

Assuntos
Compostos de Epóxi/análise , Análise de Alimentos , Contaminação de Alimentos/análise , Fórmulas Infantis/análise , alfa-Cloridrina/análise , Humanos , Lactente
2.
J Food Sci ; 84(11): 3303-3311, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31671224

RESUMO

Seven bisphenols, endocrine-disruptor chemicals, were analytically determined for risk assessment in 52 large-consumption beverages collected from the Italian market. The analytes under examination were bisphenol A, bisphenol F, bisphenol E, bisphenol B, bisphenol AF, bisphenol A diglycidyl ether, and bisphenol M. The concentration levels of all bisphenols detected ranged from

Assuntos
Compostos Benzidrílicos/análise , Bebidas/análise , Disruptores Endócrinos/análise , Fenóis/análise , Cerveja/análise , Compostos de Epóxi/análise , Contaminação de Alimentos/análise , Alimentos em Conserva/análise , Humanos , Itália
3.
Artigo em Inglês | MEDLINE | ID: mdl-31437078

RESUMO

This study was conducted to investigate on the effect of different sampling regions of palm-refined oils and fats on the 2- and 3-monochloropropanediol fatty acid esters (MCPDE) and glycidol fatty acid esters (GE) levels. The American Oil Chemists' Society (AOCS) Official Method Cd 29a-13 on the determination of MCPDE and GE in edible oils and fats by acid transesterification was successfully verified and optimised, with slight modification using 7890A Agilent GC system equipped with 5975C quadrupole detector. The determined limits of detection (LOD) for MCPDE were 0.02 mg kg-1 and 0.05 mg kg-1 for GE. The method performance has showed good recovery between 80% and 120% for all pertinent compounds with seven replicates assayed in three separate days. Round robin test with two European laboratories, i.e. Eurofins and SGS, has shown compliance results with those of the present study. Among the sampling regions, only one refinery located in the central region of Malaysia showed a significant increment of the MCPDE and GE levels after refining process. The GE level averaging at 2.5 mg kg-1 was slightly higher than that of 3-MCPDE averaging at 1.3 mg kg-1. Both esters were preferentially partitioned into the liquid phase rather than the solid phase after fractionation. However, the overall results exhibited no direct correlation between the esters content and the different sampling locations of the palm oil products in Malaysia. Analysis of total chlorine content also displayed significant variations between sampling locations which clearly show its effect on the chlorine content in the CPO samples.


Assuntos
Compostos de Epóxi/análise , Ésteres/análise , Contaminação de Alimentos/análise , Glicerol/análogos & derivados , Óleo de Palmeira/química , Propanóis/análise , alfa-Cloridrina/análise , Ácidos Graxos/análise , Análise de Alimentos , Glicerol/análise , Malásia , Reprodutibilidade dos Testes
4.
J Pharm Biomed Anal ; 174: 57-62, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31154094

RESUMO

The determination of genotoxic impurities, which is closely related to toxicological concern and daily dose, plays a key role in drug quality control. Epoxide impurity is a kind of genotoxic impurity with an epoxy ring structure during the synthesis process of sarpogrelate hydrochloride. According to the sarpogrelate hydrochloride daily dose, epoxide impurity is limited to the under 5 ppm level. The liquid chromatographic-tandem mass spectrometric (LC/MS/MS) or the gas chromatography-mass spectrometric (GC/MS) method is commonly used to characterize the epoxide impurity of sarpogrelate hydrochloride intermediates. However, these methods are not simple or economical enough to detect epoxide impurity. In this study, we resolved the problem by using the most common UV method with two ideas: one was to improve the absolute sensitivity, and the other was to reduce matrix effects. Both ultra high-performance liquid chromatography (UHPLC with high sensitivity LightPipe™ flow cells) and column-switching liquid chromatography methods were developed and validated for the quantitative determination of epoxide impurity in sarpogrelate hydrochloride intermediates. The limits of detection (LODs) of the UHPLC and column-switching liquid chromatography methods were 0.09 ppm (0.09 µg/g) and 0.33 ppm (0.33 µg/g), and the recovery rates of both methods were 87.2%-132.1% and 97.4%-100.1%, respectively. Both methods established and provided guidance for analysts to develop procedures for impurity control, especially for structures of impurity with similar matrices.


Assuntos
Contaminação de Medicamentos , Compostos de Epóxi/análise , Succinatos/análise , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Cromatografia Gasosa-Espectrometria de Massas , Limite de Detecção , Modelos Lineares , Controle de Qualidade , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Antagonistas da Serotonina/análise
5.
Food Chem ; 294: 67-72, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31126506

RESUMO

Cases of honey poisoning have been reported widely, meaning there is a need for methods that detect "mad honey" or honey contaminated with plant-derived toxins to protect human health. In this study, we compared whole flower extracts and honey from Tripterygium wilfordii Hook. f. (TwHf) and Macleaya cordata (Willd) R. Br (McRB) using QuEChERS (quick, easy, cheap, effective, rugged, and safe) and ultra-high-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UHPLC/Q-TOF-MS). The results revealed several compounds common to whole flowers and honey samples. Triptolide and protopine were selected as potential markers for identifying "mad honeys" from these plants. The developed method can easily detect different honey varieties that were spiked with 5% TwHf and McRB honey samples. Additionally, 90 commercial honey samples were analyzed and determined as free from contamination. The method described in this report could be useful for studies on honey from other poisonous nectar and pollen plants.


Assuntos
Cromatografia Líquida de Alta Pressão , Mel/análise , Papaveraceae/química , Espectrometria de Massas por Ionização por Electrospray , Toxinas Biológicas/análise , Tripterygium/química , Benzofenantridinas/análise , Alcaloides de Berberina/análise , Diterpenos/análise , Compostos de Epóxi/análise , Humanos , Papaveraceae/metabolismo , Fenantrenos/análise , Tripterygium/metabolismo
6.
J AOAC Int ; 102(4): 1205-1220, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30992094

RESUMO

Background: Fatty acid esters of glycidol, 2-Monochloropropanediol (MCPD), and 3-MCPD are heat-induced foodborne processing contaminants with possible adverse health effects. These compounds occur frequently in refined edible oils. Consequently, glycidyl esters and 2- and 3-MCPD esters might also be present in foods that contain refined edible oils. Objective: This manuscript describes the single-laboratory validation of an analytical method for the quantitative determination of glycidol, 2-MCPD, and 3-MCPD present as fatty acid esters or as free 2- or 3-MCPD in infant and adult/pediatric nutritional formula. Methods: Technically, the presented method is based on the combination of a Heat-Ultrasound Pressure-supported Solvent Extraction and a GC-MS determination of glycidol, 2-MCPD, and 3-MCPD. From a chemical perspective, the method includes an alkaline catalyzed transesterification, conversion of the unstable glycidol into monobromopropanediol, and the parallel derivatization of all analytes with phenylboronic acid. Results: Validation results showed that method linearity for all analytes in powdered and liquid infant formula ranged from 0.9981 to 0.9999 (n = 18). Repeatability relative standard deviation values for concentration levels between 1.3 µg/kg and 331 µg/kg were in the range of 1 to 12%. Relative recoveries were found to be between 93 and 107%. The analytes were quantifiable down to 5-10 µg/kg in powdered samples and 1-2 µg/kg in liquid samples. Conclusions: The reported results met actual AOAC Standard Method Performance Requirements. Highlights: In terms of consumer protection, the presented method is a novel approach for the sensitive and accurate determination of glycidol, 2-MCPD, and 3-MCPD in infant formula and related foodstuffs.


Assuntos
Compostos de Epóxi/análise , Contaminação de Alimentos/análise , Glicerol/análogos & derivados , Fórmulas Infantis/análise , Propanóis/análise , alfa-Cloridrina/análise , Adulto , Criança , Cromatografia Gasosa-Espectrometria de Massas/métodos , Glicerol/análise , Humanos , Lactente , Extração Líquido-Líquido/métodos , Extração em Fase Sólida/métodos
7.
Plant Foods Hum Nutr ; 74(2): 216-222, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30838503

RESUMO

Shortbread biscuits have become one of the most desirable snacks in all population groups but due to its high fat content it is searching for new solutions of fat reduction such as the use of carbohydrate-based fat mimetics. However, the thermal processing of food containing lipids in the presence of certain carbohydrates can contribute to the formation of toxic compounds or alter its levels. Therefore, the aim of the study was to evaluate the use of inulin and pectin gels as partial fat replacers (10-40%) in classical shortbread biscuits in a view of the changes of 3-monochloropropane-1,2-diol ester (3-MCPDE) and glycidyl ester (GE) levels after baking, and also after a two-months storage. The experiment showed that the amount of inulin gel higher than 10% promoted the endogenous formation of 3-MCPDE probably due to the higher amount of Maillard products formed in the biscuits, but after two months the levels decreased and were comparable with those transferred from shortening. Pectin did not demonstrate such phenomenon, owing to the presence of bound water in gel. Glycidyl esters were partially decomposed during baking and also during storage, particularly in the samples with the addition of pectin gel, which presumably caused by low stability of GE under acidic conditions resulting from the occurrence of galacturonic acid in pectin.


Assuntos
Carboidratos/farmacologia , Gorduras na Dieta/farmacologia , Compostos de Epóxi/análise , Substitutos da Gordura/farmacologia , alfa-Cloridrina/análise , Pão , Ésteres/análise , Análise de Alimentos , Inulina/farmacologia , Pectinas/farmacologia
8.
J Pharm Biomed Anal ; 168: 102-112, 2019 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-30802749

RESUMO

Triptolide colloidal gold immunoassay strip was prepared by using colloidal gold labeled monoclonal antibody purified with saturated ammonium sulfate, triptolide succinate-bovine serum albumin and sheep anti-mouse IgG for the first time in our lab. Under optimized conditions, the detection limit of TP strip prepared in this study were determined to be 1 µg/mL and the total analysis time (including sample preparation) was less than 50 min. Sixty-six batches of Tripterygium wilfordii (T. wilfordii) and its adulterations were analyzed. It was found that 28 batches of T. wilfordii were positive as detected by the strips and 38 batches were negative. The result of test strip detection was in consistent with that from the UFLC-ESI-MS/MS method. Gold immunochromatography assay was demonstrated as a rapid, cost-effective, reliable technique for on-site screening of T. wilfordii and its preparations. The prepared colloidal gold immunoassay strip can be conveniently used for rapid identification of triptolide containing products.


Assuntos
Anticorpos Monoclonais/imunologia , Diterpenos/análise , Imunoensaio/métodos , Fenantrenos/análise , Tripterygium/química , Animais , Bovinos , Diterpenos/química , Compostos de Epóxi/análise , Coloide de Ouro/química , Imunoglobulina G/imunologia , Limite de Detecção , Fitas Reagentes , Soroalbumina Bovina , Ovinos , Espectrometria de Massas em Tandem/métodos
9.
Artigo em Inglês | MEDLINE | ID: mdl-30652962

RESUMO

The effects of the presence of chloride on the formation of 3-monochloro-1,2-propanediol fatty acid esters (3-MCPDEs) and glycidol fatty acid esters (GEs) in saltwater fish, meats and acylglycerols (diacylglycerol and triacylglycerol) during heating were investigated in this study. Five saltwater fish species (salmon, saury, yellowtail, mackerel and Spanish mackerel) were grilled with a fish griller. 3-MCPDEs and GEs were detected in all of the grilled fish samples. The total amount of GEs was higher than 3-MCPDEs. Beef and pork patties with or without sodium chloride (1.5%) were cooked using gaseous fuel. The formation of 3-MCPDEs was significantly increased by the addition of sodium chloride to the meat patties, whereas the concentration of GEs in the cooked meat patties was not changed by the content of sodium chloride. Hexadecane solutions of diacylglycerol or triacylglycerol containing FeCl3 were heated at 240°C. The formation of 3-MCPDEs was greatly increased by adding FeCl3 to the solutions of triacylglycerol. The amounts of 3-MCPDEs decreased with the extension of the heating time. From these results, it is suggested that 3-MCPDEs and GEs are formed in saltwater fish and meats by cooking, and that the formation of 3-MCPDEs was affected by chloride in foodstuffs.


Assuntos
Cloretos/química , Compostos de Epóxi/análise , Ésteres/análise , Ácidos Graxos/análise , Glicerídeos/análise , Calefação , Propanóis/análise , alfa-Cloridrina/análise , Animais , Peixes , Contaminação de Alimentos/análise , Carne/análise
10.
Sci Total Environ ; 648: 442-449, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30121043

RESUMO

Despite high production and usage of bisphenols including bisphenol A (BPA) as well as bisphenol A diglycidyl ether and its derivatives (BADGEs), little is known about the occurrence and fate of these substances in wastewater treatment plants (WWTPs) in the U.S. In this study, we investigated the occurrence, removal, mass flows, and fate of eight bisphenol analogues and six BADGEs based on the concentrations measured in influent, primary effluent, final effluent, and sludge from two WWTPs (WWTPA and WWTPB) in the Albany area of New York State, USA. BPA, bisphenol F, bisphenol S, and BADGE·2H2O were the predominant compounds found in influents of both WWTPs, at respective geometric mean (GM) concentrations of 90.0, 90.2, 31.2, and 6.48 ng/L in WWTPA, and 53.3,

Assuntos
Compostos Benzidrílicos/análise , Compostos de Epóxi/análise , Fenóis/análise , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água/análise , New York
11.
Cient. dent. (Ed. impr.) ; 15(3): 179-185, sept.-dic. 2018. graf, tab
Artigo em Espanhol | IBECS | ID: ibc-182250

RESUMO

El bisfenol A (BPA, por sus siglas en inglés) es un producto químico utilizado en la producción de policarbonatos y resinas epoxi, cuyo uso está muy extendido en la industria. El BPA puede pasar al organismo por medio de la dieta, ya que sus moléculas tienen migración probable de los recipientes fabricados con este producto a los alimentos contenidos en dichos recipientes. La presencia de BPA en los materiales de uso odontológico está muy extendida. Una gran cantidad de productos están elaborados con resinas epoxi (procedentes de la reacción entre la epiclorohidrina y el bisfenol A). El presente estudio se analizaron cuatro cementos de uso endodóntico basados en resina (Ah 26(R), Ah Plus(R), TopSeal(R) y Simpliseal(R)) a través de un procedimiento de extracción líquido-sólido y análisis en cromatógrafo de gases acoplado a espectrometría de masas. Los resultados obtenidos muestran valores alarmantemente superiores a los 5x10-6% en peso que permite la Unión Europea para la migración de BPA desde el envase al alimento, obteniéndose unos valores de 7% (Simpliseal(R)); 22% (AH 26(R)); 46% (TopSeal(R)) y 74% (AH Plus(R)). El presente estudio es pionero en el estudio de la concentración de BPA en materiales endodónticos


Bisphenol A (BPA) is a compound used in the production of polycarbonates and epoxy resins and is widely used in the industry. BPA can be passed into the body through the diet, since its molecules can easily migrate from the containers made with BPA to the food in those containers. The presence of BPA in dental materials is very common. A large number of products are made with epoxy resins (from the reaction between epichlorohydrin and bisphenol A). This study analyzed four resin-based endodontic cements (Ah 26(R), Ah Plus(R), TopSeal(R) and Simpliseal(R)) using a liquid-solid extraction procedure and gas chromatograph analysis coupled to mass spectrometry. The results obtained show alarmingly higher values than the 5x10-6% by weight that the European Union allows for the migration of BPA from packaging to food, obtaining values of 7% (Simpliseal(R)), 22% (AH 26(R)), 46% (TopSeal(R)) and 74% (AH Plus(R)). This study is a pioneer in the investigation of the concentration of BPA in endodontic materials


Assuntos
Humanos , Cimentos Dentários/análise , Bis-Fenol A-Glicidil Metacrilato/análise , Bis-Fenol A-Glicidil Metacrilato/química , Endodontia/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Materiais Restauradores do Canal Radicular/análise , Compostos de Epóxi/análise
12.
Chirality ; 30(12): 1321-1329, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30375664

RESUMO

In this study, magnetic multiwalled carbon nanotubes (MMWCNTs) were synthesized and used as adsorbent for preconcentration of chiral pesticide residues (including epoxiconazole, tebuconazole, and metalaxyl) in lettuce, cabbage, and apple. Several parameters affecting the treatment efficiency were investigated, including extraction solvent and absorption solvent. Under the optimal conditions, all three chiral pesticides showed decent enantiomeric separation (Rs > 1.48). The linearity of each target was good with the correlation coefficient (r2 ) being greater than 0.9923. The average recoveries of the three spiked levels were 73.4% to 110.9% with repeatability (RSDr ) less than 7.6%, and the limit of quantification of the method was 0.10 to 0.25 mg·kg-1 . The results indicated that MMWCNTs had a good purifying effect, which can be applied as an effective pretreatment tool for the determination of residual chiral pesticides in fruits and vegetables.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Frutas/química , Nanotubos de Carbono/química , Resíduos de Praguicidas/análise , Verduras/química , Alanina/análogos & derivados , Alanina/análise , Calibragem , Fracionamento Químico/instrumentação , Fracionamento Químico/métodos , Cromatografia Líquida de Alta Pressão/instrumentação , Compostos de Epóxi/análise , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Magnetismo , Resíduos de Praguicidas/química , Resíduos de Praguicidas/isolamento & purificação , Reprodutibilidade dos Testes , Solventes , Espectroscopia de Infravermelho com Transformada de Fourier , Estereoisomerismo , Triazóis/análise
13.
J Chromatogr Sci ; 56(10): 920-932, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29982404

RESUMO

Gradient reversed-phase high-performance liquid chromatography with photodiode array detection was used for separation, detection and quantification of bisphenol-A-diglycidyl ether (BADGE) and some of its reaction products, namely, BADGE·HCl·H2O, BADGE·H2O and BADGE·2HCl in pure form and in canned foods, where canned beans and tuna were used as representatives of aqueous and oil-in-water food matrices, respectively. The proposed method had a linear range of 0.01-0.5 µg g-1 for BADGE·HCl·H2O, BADGE·H2O, BADGE·2HCl and 0.02-0.7 µg g-1 for BADGE in aqueous food matrices. In oil-in-water matrices, the method was proven to be sensitive over a linear range of 0.01-0.5 µg g-1 for BADGE·HCl·H2O, BADGE·H2O and 0.02-0.7 µg g-1 for BADGE·2HCl and BADGE. The limits of detection and quantification ranged from 0.24 to 1.22 ng g-1 and 0.73 to 14.07 ng g-1, respectively. Excellent intraday and interday precision (n = 9) were obtained with RSD% of 0.84-2.19% and 1.88-2.52%, respectively. Accuracy was measured at five concentration levels and the recoveries ranged from 96.31% to 98.76% with an acceptable variation of ±0.9-2.87. Results suggest that the proposed method could be applied for the routine analysis of the studied compounds in their laboratory-prepared mixtures and in various types of canned foods following the limits and regulations of the European Union.


Assuntos
Compostos Benzidrílicos/análise , Cromatografia Líquida de Alta Pressão/métodos , Compostos de Epóxi/análise , Contaminação de Alimentos/análise , Alimentos em Conserva/análise , Compostos Benzidrílicos/química , Compostos de Epóxi/química , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes
14.
Spectrochim Acta A Mol Biomol Spectrosc ; 203: 443-449, 2018 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-29894958

RESUMO

Two multivariate calibration methods, namely principal component regression (PCR) and partial least squares (PLS-2) have been developed, validated and compared for the simultaneous determination of bisphenol-A-diglycidyl ether (BADGE) and some of its reaction products, including BADGE·HCl·H2O, BADGE·H2O and BADGE·2HCl. Chemometrics allowed rapid, accurate and precise simultaneous quantification of the analytes of interest which was not possible by other spectrophotometric methods due to their severe spectral overlap. PCR and PLS-2 techniques successfully quantified BADGE, BADGE·HCl·H2O, BADGE·H2O and BADGE·2HCl in the ranges of 1.4-3.4, 1-5, 1-4.2 and 1-7 µg mL-1, respectively. The constructed models were validated according to the International Conference on Harmonization guidelines and successfully applied for the determination of these compounds in pure form, laboratory prepared mixtures and in various types of canned foods following the limits and regulations of the European Union (EU) where satisfactory recovery results were obtained.


Assuntos
Compostos Benzidrílicos/análise , Compostos de Epóxi/análise , Alimentos em Conserva/análise , Espectrofotometria/métodos , Compostos Benzidrílicos/química , Calibragem , Egito , Compostos de Epóxi/química , Análise dos Mínimos Quadrados , Análise de Componente Principal , Reprodutibilidade dos Testes
15.
Nutrition ; 54: 26-32, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29729504

RESUMO

OBJECTIVE: Gastroesophageal reflux disease is very common in industrialized countries and rapidly and significantly increasing even in developing countries. The approach in this study is one not commonly found to date in the scientific literature. To assess the ability of reduced-carbohydrate diets and foods that are enriched with acid potential of hydrogen (pH; lemon and tomato) to quickly and exponentially reduce symptoms that are related to conditions such as gastritis and gastroesophageal reflux and unrelated to Helicobacter pylori. METHODS: After the administration of an anamnestic test, 130 patients were selected including 73 women and 57 men, 21 to 67 y, and with a gastritis diagnosis for 92 patients (56 women, 36 men) and reflux gastritis for 38 patients (17 women, 21 men). Study participants followed three dietary treatments in succession. Each treatment lasted 2 wk and treatments were separated by 2 wk of washout. The patients followed a diet that consisted primarily of proteins and fats and included the exponential reduction of glycides (simple and complex). In addition, the treatment provided for the daily intake of the juice of two lemons and approximately 100 g of fresh orange tomato without seeds eaten either raw or cooked and peeled. RESULTS: During treatment and at the end of 2 wk of treatment, the patients reported significant improvements including an almost total disappearance of symptoms that were related to the disease in question. CONCLUSIONS: This study shows that a carbohydrate-free diet and/or highly hypoglycidal diet that is enriched with acid pH foods appears to lead to a decrease in the pH of the gastric contents, thus inhibiting the further production of hydrochloric acid with a reduction or disappearance of heartburn symptoms that are typical of gastroesophageal diseases.


Assuntos
Dieta com Restrição de Carboidratos/métodos , Dieta/métodos , Gastrite/dietoterapia , Refluxo Gastroesofágico/dietoterapia , Adulto , Idoso , Citrus/química , Compostos de Epóxi/análise , Feminino , Sucos de Frutas e Vegetais/análise , Ácido Gástrico/química , Determinação da Acidez Gástrica , Humanos , Concentração de Íons de Hidrogênio , Lycopersicon esculentum/química , Masculino , Pessoa de Meia-Idade , Propionatos/análise , Resultado do Tratamento , Adulto Jovem
16.
Artigo em Inglês | MEDLINE | ID: mdl-29620437

RESUMO

A dietary exposure assessment was conducted for 3-monochloropropane-1,2-diol (3-MCPD) esters (3-MCPDE) and glycidyl esters (GE) in infant formulas available for consumption in the United States. 3-MCPDE and GE are food contaminants generated during the deodorisation of refined edible oils, which are used in infant formulas and other foods. 3-MCPDE and GE are of potential toxicological concern because these compounds are metabolised to free 3-MCPD and free glycidol in rodents and may have the same metabolic fate in humans. Free 3-MCPD and free glycidol have been found to cause adverse effects in rodents. Dietary exposures to 3-MCPDE and GE from consumption of infant formulas are of particular interest because formulas are the sole or primary food source for some infants. In this analysis, US Food and Drug Administration data on 3-MCPDE and GE concentrations (as 3-MCPD and glycidol equivalents, respectively) in a small convenience sample of infant formulas were used to estimate exposures from consumption of formula by infants 0-6 months of age. 3-MCPDE and GE exposures based on mean concentrations in all formulas were estimated at 7-10 and 2 µg/kg bw/day, respectively. Estimated mean exposures from consumption of formulas produced by individual manufacturers ranged from 1 to 14 µg/kg bw/day for 3-MCPDE and from 1 to 3 µg/kg for GE.


Assuntos
Compostos de Epóxi/análise , Ésteres/análise , Contaminação de Alimentos/análise , Fórmulas Infantis/química , Propanóis/análise , alfa-Cloridrina/análise , Humanos , Lactente , Recém-Nascido , Estados Unidos
17.
Food Chem ; 259: 130-138, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29680035

RESUMO

Screening carotenoids of elite accessions of yam (Dioscorea spp.) used in the global yam breeding program has been conducted to quantitatively determine the carotenoid composition of the crop. Comparisons to previous data reporting cerotenoid levels in yam has been made, in order to deduce greater perspectives across multiple studies. Characterisation of complex species and accession -specific profiles have shown a rich base of diversity that can inform breeding strategies. Key findings include; (i) the identification of accessions rich in ß-carotene which can aid provitamin A biofortification, (ii) Data disputing the commonly held belief that yellow Guinea yam (D. cayennensis) has higher ß-carotene content than that of white Guinea yam (D. rotundata), and (iii) the tentative identification of C25-epoxy-apocarotenoid persicaxanthin with potential implications for tuber dormancy.


Assuntos
Carotenoides/análise , Dioscorea/química , Compostos de Epóxi/análise , Tubérculos/química , beta Caroteno/análise
18.
Pharm Biol ; 56(1): 132-137, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29385884

RESUMO

CONTEXT: Triptolide and amlodipine are often simultaneously used for reducing urine protein excretion after renal transplantation in China clinics. OBJECTIVE: This study investigated the effects of triptolide on the pharmacokinetics of amlodipine in male Sprague-Dawley rats. MATERIALS AND METHODS: The pharmacokinetics of amlodipine (1 mg/kg) with or without triptolide pre-treatment (2 mg/kg/day for seven days) were investigated using a sensitive and reliable LC-MS/MS method. Additionally, the inhibitory effects of triptolide on the metabolic stability of amlodipine were investigated using rat liver microsome incubation systems. RESULTS: The results indicated that when the rats were pre-treated with triptolide, the Cmax of amlodipine increased from 13.78 ± 3.57 to 19.96 ± 4.56 ng/mL (p < 0.05), the Tmax increased from 4.04 ± 1.15 to 5.89 ± 1.64 h (p < 0.05), and the AUC0-t increased by approximately 104% (p < 0.05), which suggested that the pharmacokinetic behaviour of amlodipine was affected after oral co-administration of triptolide. Additionally, the metabolic half-life was prolonged from 22.5 ± 4.26 to 36.8 ± 6.37 min (p < 0.05) with the pre-treatment of triptolide. CONCLUSIONS: In conclusion, these results indicated that triptolide could affect the pharmacokinetics of amlodipine, possibly by inhibiting the metabolism of amlodipine in rat liver when they are co-administered.


Assuntos
Anlodipino/análise , Anlodipino/farmacocinética , Diterpenos/análise , Diterpenos/farmacocinética , Fenantrenos/análise , Fenantrenos/farmacocinética , Espectrometria de Massas em Tandem/métodos , Animais , Anti-Hipertensivos/análise , Anti-Hipertensivos/farmacocinética , Cromatografia Líquida/métodos , Interações Medicamentosas/fisiologia , Compostos de Epóxi/análise , Compostos de Epóxi/farmacocinética , Imunossupressores/análise , Imunossupressores/farmacocinética , Masculino , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
19.
Food Chem ; 248: 93-100, 2018 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-29329876

RESUMO

In this study, the processing derived contaminants 2- and 3-monochloropropanediol (2- and 3-MCPD) esters and glycidyl esters (GEs) were analysed in 84 oil samples by GC-MS/MS for the discrimination of processing grades of olive oils as a potential authentication tool. Concentrations of 2- and 3-MCPD esters and GEs varied in the ranges 0-6 mg/kg, 0-1.5 mg/kg, and 0-1 mg/kg oil, respectively. The concentrations of the three compounds in lower grade olive oils were significantly higher (P < .001) than that in EVOO. A similar difference was observed for other refined and cold-pressed vegetable oils. The limit of fraud detection of lower grade oils in EVOO was 2% when using 3-MCPD esters, 5% for 2-MCPD esters, and 13-14% for GEs based on calculations of virtual mixtures of the current sample set. Especially the MCPD esters appear very specific and promising for the detection of lower processing grade oils in EVOO.


Assuntos
Compostos de Epóxi/análise , Contaminação de Alimentos/análise , Manipulação de Alimentos/métodos , Óleos Vegetais/análise , alfa-Cloridrina/análise , Compostos de Epóxi/química , Ésteres/análise , Ésteres/química , Glicerol/análogos & derivados , Glicerol/análise , Glicerol/química , Azeite de Oliva/análise , Azeite de Oliva/química , Óleos Vegetais/química , Espectrometria de Massas em Tandem , alfa-Cloridrina/química
20.
Environ Sci Process Impacts ; 20(2): 332-339, 2018 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-29292423

RESUMO

Isoprene-derived secondary organic aerosol (SOA), which comprise a large portion of atmospheric fine particulate matter (PM2.5), can be formed through various gaseous precursors, including isoprene epoxydiols (IEPOX), methacrylic acid epoxide (MAE), and isoprene hydroxyhydroperoxides (ISOPOOH). The composition of the isoprene-derived SOA affects its reactive oxygen species (ROS) generation potential and its ability to alter oxidative stress-related gene expression. In this study we assess effects of isoprene SOA derived solely from ISOPOOH oxidation on human bronchial epithelial cells by measuring the gene expression changes in 84 oxidative stress-related genes. In addition, the thiol reactivity of ISOPOOH-derived SOA was measured through the dithiothreitol (DTT) assay. Our findings show that ISOPOOH-derived SOA alter more oxidative-stress related genes than IEPOX-derived SOA but not as many as MAE-derived SOA on a mass basis exposure. More importantly, we found that the different types of SOA derived from the various gaseous precursors (MAE, IEPOX, and ISOPOOH) have unique contributions to changes in oxidative stress-related genes that do not total all gene expression changes seen in exposures to atmospherically relevant compositions of total isoprene-derived SOA mixtures. This study suggests that amongst the different types of known isoprene-derived SOA, MAE-derived SOA are the most potent inducer of oxidative stress-related gene changes but highlights the importance of considering isoprene-derived SOA as a total mixture for pollution controls and exposure studies.


Assuntos
Poluentes Atmosféricos/toxicidade , Butadienos/química , Células Epiteliais/efeitos dos fármacos , Compostos de Epóxi/toxicidade , Expressão Gênica/efeitos dos fármacos , Hemiterpenos/química , Estresse Oxidativo/efeitos dos fármacos , Pentanos/química , Aerossóis , Poluentes Atmosféricos/análise , Linhagem Celular , Compostos de Epóxi/análise , Humanos , Oxirredução , Estresse Oxidativo/genética
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