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1.
Environ Sci Technol ; 56(12): 8541-8551, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35559607

RESUMO

Here, we investigated the use of breath-borne volatile organic compounds (VOCs) for rapid monitoring of air pollution health effects on humans. Forty-seven healthy college students were recruited, and their exhaled breath samples (n = 235) were collected and analyzed for VOCs before, on, and after two separate haze pollution episodes using gas chromatography-ion mobility spectrometry (GC-IMS). Using a paired t-test and machine learning model (Gradient Boosting Machine, GBM), six exhaled VOC species including propanol and isoprene were revealed to differ significantly among pre-, on-, and post-exposure in both haze episodes, while none was found between clean control days. The GBM model was shown capable of differentiating between pre- and on-exposure to haze pollution with a precision of 90-100% for both haze episodes. However, poor performance was detected for the same model between two different clean days. In addition to gender and particular haze occurrence influences, correlation analysis revealed that NH4+, NO3-, acetic acid, mesylate, CO, NO2, PM2.5, and O3 played important roles in the changes in breath-borne VOC fingerprints following haze air pollution exposure. This work has demonstrated direct evidence of human health impacts of haze pollution while identifying potential breath-borne VOC biomarkers such as propanol and isoprene for haze air pollution exposure.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Testes Respiratórios , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Propanóis/análise
2.
Molecules ; 26(13)2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34201697

RESUMO

The p-methoxycinnamic acid (p-MCA) is one of the most studied phenylpropanoids with high importance not only in the wide spectrum of therapeutic activities but also its potential application for the food industry. This natural compound derived from plants exhibits a wide range of biologically useful properties; therefore, during the last two decades it has been extensively tested for therapeutic and nutraceutical applications. This article presents the natural sources of p-MCA, its metabolism, pharmacokinetic properties, and safety of its application. The possibilities of using this dietary bioactive compound as a nutraceutical agent that may be used as functional food ingredient playing a vital role in the prevention and treatment of many chronic diseases is also discussed. We present the antidiabetic, anticancer, antimicrobial, hepato-, and neuroprotective activities of p-MCA and methods of its lipophilization that have been developed so far to increase its industrial application and bioavailability in the biological systems.


Assuntos
Cinamatos/química , Cinamatos/farmacologia , Anti-Infecciosos/farmacologia , Anti-Infecciosos/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Cinamatos/metabolismo , Cinamatos/uso terapêutico , Suplementos Nutricionais , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Fígado/efeitos dos fármacos , Fígado/fisiologia , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Polifenóis/análise , Polifenóis/farmacologia , Propanóis/análise , Propanóis/farmacologia
3.
J Sep Sci ; 44(17): 3199-3207, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34213832

RESUMO

A fast and simple ultra-high performance supercritical fluid chromatography method has been developed for the determination of six analytes, namely (paeonol, coumarin, cinnamic alcohol, cinnamic acid, paeoniflorin, and amygdalin) in Guizhi Fuling capsule and tablet samples. The influence of the key chromatographic parameters for the separation purposes was evaluated. The optimal column was Trefoil CEL1 column. The optimal mobile phase was a gradient mixture of carbon dioxide and methanol at flow rate of 1.0 mL/min. The back pressure of the system was set to 1.38 × 107  Pa and the temperature to 45°C. The six compounds were separated within 11 min by the proposed ultra-high performance supercritical fluid chromatography method with satisfactory resolution. Method validation confirmed that the procedure is accurate with the recovery rates from 87.04 to 104.30%, intraday precision values less than 4.81% and interday precision less than 5.22%, and linear with R2 higher than 0.9967. Therefore, this work provides a simple and novel method for the simultaneous analysis of six compounds in Guizhi Fuling capsule and tablet samples.


Assuntos
Medicamentos de Ervas Chinesas/química , Acetofenonas/análise , Amigdalina/análise , Cápsulas/análise , Cromatografia com Fluido Supercrítico , Cinamatos/análise , Cumarínicos/análise , Glucosídeos/análise , Monoterpenos/análise , Propanóis/análise , Comprimidos
4.
J Chromatogr A ; 1639: 461940, 2021 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-33548662

RESUMO

The development and validation of a method for the analysis of traces of 3-monochloropropanediol (3-MCPD) esters (19) and glycidyl esters (7) of fatty acids in vegetable oils, margarine, biscuits and croissants was performed. An extraction method based on the use of solvents (tert­butyl methyl ether (20% ethyl acetate, v/v)) was carried out and cleaning of the extract with a mixture of sorbents (Si-SAX, PSA and Z-sep+) was optimized for the elimination of fatty interferents. The analysis of the targeted compounds was carried out by ultra-high-performance liquid chromatography coupled to tandem mass spectrometry, using a triple quadrupole analyzer (UHPLC-MS/MS-QqQ). The validation of the method provided trueness values between 72 and 118% and precision lower than 20%. The limits of quantification ranged from 0.01 to 0.1 mg kg-1, which were below the current legal limits. Twenty samples of vegetable oils as well of 4 samples of margarine, biscuits and croissants were analyzed. Six out of the 24 samples (25%) exceeded the limits set by European legislation, and a maximum contamination of 3-MCPD esters at 2.52 mg kg-1 was obtained in a sample of corn oil (being 1-myristoyl-3-MCPD the compound detected at the highest concentration). A maximum concentration of glycidyl esters at 7.84 mg kg-1 was determined in a soybean oil sample (glycidyl linoleate as the main compound). Only one sample of olive oil exceeded the maximum allowable limit for 3-MCPD esters with a value of 1.72 mg kg-1, expressed as 3-MCPD.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Ésteres/análise , Espectrometria de Massas em Tandem/métodos , alfa-Cloridrina/análise , Compostos de Epóxi/análise , Ácidos Graxos/análise , Contaminação de Alimentos/análise , Limite de Detecção , Margarina/análise , Azeite de Oliva/análise , Propanóis/análise , Padrões de Referência , Reprodutibilidade dos Testes , Óleo de Soja/análise
5.
Artigo em Inglês | MEDLINE | ID: mdl-33332229

RESUMO

The study aimed to establish the detection method for bound 3-, 2-MCPD, and glycidol using accelerated solvent extraction (ASE) and gas chromatography mass spectrometry (GC-MS). The ASE was modified for reduced solvent volume and process time to extract lipid from the chocolate spread, infant formula, potato chips, and sweetened creamer. The solvent selected for ASE was a mixture of iso-hexane and acetone at 100°C with the lipid and analyte recovery ranging from 96.9% to 98.6% and 84.1% to 107.5%, respectively. The derivatisation of analytes was adopted from the AOCS method Cd29a-13 for GC-MS analysis. The results showed that the coefficient of determination (R2) of all analytes was >0.99. The limit of detection (LOD) was 0.1 mg kg-1 expressed in lipid basis for both bound 3- and 2-MCPD and 0.2 mg kg-1 expressed in lipid basis for bound glycidol. The limit of quantitation (LOQ) was 0.3 mg kg-1 expressed in lipid basis for both bound 3- and 2-MCPD and 0.6 mg kg-1 expressed in lipid basis for bound glycidol. A blank spiked with 3-monochloropropanediols fatty acid esters (MCPDE) and 2-MCPDE (0.3, 2.1, and 7.2 mg kg-1) and glycidol esters (0.6, 4.7, and 16.6 mg kg-1) were chosen for accuracy and precision tests. The recoveries were 91.7% to 105.9%. Both repeatability and within-laboratory reproducibility of the analysis were within the acceptable level of precision ranging from 1.7% to 16%. This is the first time that a full validation procedure extending to both accuracy and precision tests has been carried out for sweetened creamer and chocolate spread. Overall, the combined protocol of ASE and AOCS Cd29a-13 was successfully validated for both solid and liquid food samples with lipid content from 10% to 30%.


Assuntos
Compostos de Epóxi/análise , Análise de Alimentos , Contaminação de Alimentos/análise , Glicerol/análogos & derivados , Propanóis/análise , alfa-Cloridrina/análise , Cromatografia Gasosa-Espectrometria de Massas , Glicerol/análise , Solventes/química
6.
Artigo em Inglês | MEDLINE | ID: mdl-33332977

RESUMO

The dietary exposures to fatty esters of 3- and 2-monochloropropanediol (MCPD) and glycidol were estimated for children aged 2- to 3-year-old from two areas of China using duplicate diet collection method. The 24-h daily duplicate diet samples over three consecutive days were collected from 40 healthy children aged between 26 and 36 months. The analysis of these contaminates in food samples was measured by an indirect method that entails MCPD/glycidol cleavage from their esterified forms for GC-MS analysis. Over 71% of the mixed diet and dairy products samples were found to be contaminated with 3-MCPD and glycidyl esters. The estimated daily exposure to bound 3-MCPD (mean: 0.48-0.49 µg kg-1 bw day-1; P95: 1.00-1.11 µg kg-1 bw day-1) were well below the health guidance values and were considered of low safety concern. The daily exposure to bound 2-MCPD was estimated to be 0.031-0.038 µg kg-1 bw day-1 on average and 0.12-0.14 µg kg-1 bw day-1 for the P95 exposure. However, it was not possible to assess its risk due to the lack of health guidance value of 2-MCPD. The margin of exposure (MOE) estimates for the mean exposure to bound glycidol (0.10-0.12 µg kg-1 bw day-1) were far above 10000 and were considered of low safety concern. However, the margin of exposure estimates for the P95 bound glycidol exposure (0.41-0.45 µg kg-1 bw day-1) were below 10000 and indicated a health concern. Our data indicated that the mixed diet accounted for nearly 76% to 91% of bound MCPD and glycidol exposure. In addition, the follow-on formula was also an important source for the children aged 2-3 years.


Assuntos
Exposição Dietética/análise , Compostos de Epóxi/análise , Contaminação de Alimentos/análise , Glicerol/análogos & derivados , Propanóis/análise , Escolas Maternais , alfa-Cloridrina/análise , Pré-Escolar , China , Ésteres/análise , Ácidos Graxos/análise , Feminino , Análise de Alimentos , Glicerol/análise , Humanos , Masculino
7.
Anal Biochem ; 609: 113971, 2020 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-32979368

RESUMO

Enzyme immobilization using inorganic membranes has enticed increased attention as they not only improve enzyme stability, but also furnish user-friendly biodevices that can be tailored to different applications. Herein, we explored the suitability of the glass fiber membrane for enzyme immobilization and its application for halocarbon detection. For this, halohydrin dehalogenase (HheC) and bovine serum albumin were crosslinked and immobilized on a glass fiber membrane without membrane functionalization. Immobilized HheC exhibited higher storage stability than its free counterpart over 60 days at 4 °C (67% immobilized vs. 8.1% free) and 30 °C (77% immobilized vs. 57% free). Similarly, the thermal endurance of the immobilized HheC was significantly improved. The practical utility of the membrane-immobilized enzyme was demonstrated by colorimetric detection of 1,3-dichloro-2-propanol (1,3-DCP) and 2,3-dibromo-1-propanol (2,3-DBP) as model analytes. Under optimized conditions, the detection limits of 0.06 mM and 0.09 mM were achieved for 1,3-DCP and 2,3-DBP, respectively. The satisfactory recoveries were observed with spiked river and lake water samples, which demonstrate the application potential of immobilized HheC for screening contaminants in water samples. Our results revealed that the proposed frugal and facile approach could be useful for enzyme stabilization, and mitigation of halocarbon pollution.


Assuntos
Colorimetria/métodos , Vidro/química , Hidrolases/metabolismo , Propanóis/análise , alfa-Cloridrina/análogos & derivados , Agrobacterium tumefaciens/enzimologia , Estabilidade Enzimática , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Água Doce/análise , Concentração de Íons de Hidrogênio , Hidrolases/química , Hidrolases/genética , Limite de Detecção , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Temperatura , Poluentes Químicos da Água/análise , alfa-Cloridrina/análise
8.
Food Addit Contam Part B Surveill ; 13(4): 305-312, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32772639

RESUMO

Dietary supplements based on fish oils might be contaminated with thermal processing contaminants, which are generated during the fish oil deodorisation. In the study, 30 samples of dietary supplements were analysed in terms of the occurrence of 3-monochloropropane-1,2-diol esters (3-MCPDE), 2-monochloropropane-1,3-diol esters (2-MCPDE) and glycidyl esters (GE). The results showed that the highest levels of 3-MCPDE (mean: 1461 µg kg-1) as well as 2-MCPDE (mean: 357 µg kg-1) were observed in the products containing shark liver oil. In the case of GE, they were mainly detected in the supplements including shark liver and cod liver oils. Although the results indicated that the consumption of the investigated supplements constituted no more than 1% of tolerable daily intake (TDI), the occurrence of MCPDE and GE in fish oil dietary supplements with a special attention to the origin of ester precursors should be thoroughly investigated in further studies.


Assuntos
Suplementos Nutricionais/análise , Óleos de Peixe/análise , Contaminação de Alimentos/análise , Glicerol/análogos & derivados , alfa-Cloridrina/análise , Animais , Óleo de Fígado de Bacalhau/química , Diglicerídeos/análise , Compostos de Epóxi/análise , Ésteres/análise , Glicerol/análise , Humanos , Fígado/química , Concentração Máxima Permitida , Propanóis/análise , Tubarões
9.
Chemosphere ; 251: 126469, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32443245

RESUMO

Cinnamic acid was chosen as an exemplar molecule to study the effect of potential contaminants on the kinetics and mechanism of the photocatalytic destruction of hydrocarbons in aqueous solutions. We identify the principal intermediates in the photocatalytic reaction of the acid and corresponding alcohol, and propose a mechanism that explains the presence of these species. The impact of two likely contaminants of aqueous systems, sulfate and chloride ions were also studied. Whereas sulfate ions inhibit the degradation reaction at all concentrations, chloride ions, up to a concentration of 0.5 M, accelerate the removal of cinnamic acid from solution by a factor of 1.6. However, although cinnamic acid is removed, the pathway to complete oxidation is blocked by the chloride, with the acid being converted (in the presence of oxygen) into new products including acetophenone, 2-chloroacetophenone, 1-(2-chlorophenyl)ethenone and 1,2-dibenzoylethane. We speculate that the formation of these products involves chlorine radicals formed from the reaction of chloride ions with the photoinduced holes at the catalyst surface. Interestingly, we have shown that the 1-(2-chlorophenyl)ethenone and 1,2-dibenzoylethane products form from 2-chloroacetophenone when irradiated with 365 nm light in the absence of the catalyst. The formation of potentially dangerous side products in this reaction suggest that the practical implementation of the photocatalytic purification of contaminated water needs to considered very carefully if chlorides are likely to be present.


Assuntos
Cinamatos/análise , Luz , Propanóis/análise , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Catálise , Cloro/química , Cinamatos/efeitos da radiação , Oxirredução , Propanóis/efeitos da radiação , Sulfatos/química , Titânio/química , Poluentes Químicos da Água/efeitos da radiação
10.
Artigo em Inglês | MEDLINE | ID: mdl-32077805

RESUMO

Fatty acid esters of 3-monochloropropanediol (3-MCPD), 2-MCPD and glycidol (Gly) are food-processing contaminants that cause concerns about possible adverse health effects. The present study evaluates the contamination levels of the three ester classes in 130 samples of foodstuffs marketed in Italy covering 10 food categories, namely margarines, oils, roasted coffee, breakfast cereals, salted crackers, cookies, infant biscuits, rusks, breads and potato crisps. The analytical method employed is a so-called indirect method that entails MCPD/glycidol cleavage from their esterified forms, cleanup, derivatisation and GC-MS analysis. The MCPDs and glycidol concentrations (from esters) were found to be equal or a little higher than the levels reported in previous studies conducted in other European countries and described in the literature. 3-MCPD was the predominant compound in all foodstuffs analysed with the exception for rusks where Gly levels were slightly higher. Considering the sum of MCPD and Gly esters, the most contaminated foodstuffs were seed oils, followed by margarines and cookies, whereas roasted coffee, bread, rusks, cornflakes and infant biscuits were less contaminated with MCPDs and Gly concentrations often below LOQ or LOD values. Refined olive oil, potato chips and salted crackers showed contamination levels intermediate between the two above groups. The results of this study also confirm that the use of palm oil as an ingredient or frying medium is an important cause of increase of the levels of MCPD and Gly esters, especially in salted crackers, rusks and potato crisps. Finally, the Italian intake of 3-MCPD due to the various foods analysed has been calculated and related to TDI. The MoE for Gly was also estimated.


Assuntos
Compostos de Epóxi/análise , Ésteres/análise , Ácidos Graxos/análise , Análise de Alimentos , Contaminação de Alimentos/análise , Glicerol/análogos & derivados , Propanóis/análise , Manipulação de Alimentos , Glicerol/análise , Humanos , Itália
11.
Artigo em Inglês | MEDLINE | ID: mdl-31917641

RESUMO

Fatty acid esters of 3-monochloropropane-1,2-diol (3-MCPD) and glycidol are potentially carcinogenic and/or genotoxic processing contaminants that are formed during the process of edible oil refining. Because of their toxicological properties, the presence of these compounds in refined oils and foods containing these oils, particularly infant formula, poses a potential food safety concern. For this reason, recent research efforts have focussed on the development of methods for the analysis of MCPD and glycidyl esters in infant formula in order to estimate levels of exposure. This work presents occurrence data for 3-MCPD and glycidyl esters in 222 infant formulas purchased in the United States between December 2017 and January 2019. The results of this study show a wide range of contaminant concentrations across four different manufacturers, with average bound 3-MCPD concentrations ranging from 0.035 µg g-1 to 0.63 µg g-1 and average bound glycidol concentrations ranging from 0.019 µg g-1 to 0.22 µg g-1. The data suggest that manufacturers B and C source palm oil produced with mitigation measures, leading to reduced amounts of 3-MCPD and glycidyl esters in their infant formulas. Additionally, comparison with a previously published study in our laboratory of the occurrence of 3-MCPD and glycidyl esters in infant formula purchased in the U.S. between 2013 and 2016 revealed that, since 2016, contaminant concentrations have decreased in products produced by manufacturers A, B, and C, while contaminant amounts in formulas from manufacturer D have slightly increased.


Assuntos
Compostos de Epóxi/análise , Ésteres/análise , Ácidos Graxos/análise , Fórmulas Infantis/análise , Propanóis/análise , alfa-Cloridrina/análise , Estados Unidos
12.
Vopr Pitan ; 89(6): 113-122, 2020.
Artigo em Russo | MEDLINE | ID: mdl-33476504

RESUMO

Monochlorpropanediol fatty acid esters (MCPDE) and glycidyl fatty acid esters (GE) are mainly considered to be processing contaminants and their concentration can rise during high temperature refining and deodorization of edible oils. Free forms formed during digestive hydrolysis of esters such as 3-monochloropropane-1,2-diol (3-MCPD), 2-MCPD and glycidol can provoke a negative effect on human health. Therefore the quantitative determination of MCPDE and GE in edible oils, fats and fat blends is needed. The aim - this manuscript deals with MCPDE and GE concentration measured as free 3-MCPD, 2-MCPD and glycidol in different edible oils, fats and fat blends of Russian market. Material and methods. 55 edible oil and fat samples sold on Russian market including refined and non-refined oils and fat blends such as spreads, dairy fat replacers, and margarines have been analyzed. Slow alkaline transesterification method with GC-MS/MS was used. Results. According to the data obtained, the highest concentrations of the contaminants were detected in fat blends: <0.10-5.03 mg/kg for 3-MCPD, <0.10-2.50 mg/kg for 2-MCPD and 0.1 5-11.17 mg/kg for glycidol. In palm oils and its fractions concentration of 3-MCPD was <0.10-6.61 mg/kg, 2-MCPD - <0.10-2.69 mg/kg and glycidol - <0.10-6.29 mg/kg. The content of glycidol in sunflower oils fluctuated in the range <0.10-1.19 mg/kg, 3-MCPD was <0.10-2.47 mg/kg, and 2-MCPD <0.10-0.67 mg/kg. Non-refined edible oils and olive oils had no or little MCPDE or GE. Conclusion. In this work we indicate high importance of monitoring MCPDE and GE in edible oils and fats both as ready-to-eat products and as ingredients prior to the Russian market release. There is strong need in mitigation of these process contaminants during fat blends manufacturing.


Assuntos
Gorduras na Dieta/análise , Compostos de Epóxi/análise , Contaminação de Alimentos/análise , Glicerol/análogos & derivados , Óleos de Plantas/análise , Propanóis/análise , Espectrometria de Massas em Tandem , alfa-Cloridrina/análise , Esterificação , Glicerol/análise , Humanos , Federação Russa
13.
Food Chem ; 309: 125513, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31683147

RESUMO

The present study aims at synthesizing and in vitro antibacterial activity evaluation of chitosan oligosaccharide (COS) modified by Cinnamyl alcohol (Cin) onto the OH position of COS. Three different degrees of substitution (DS) COS-O-Cin1-3 were synthesized by changing different molar ratios of COS to Cin. UV-visible spectroscopy (UV-vis), Fourier transform infrared (FT-IR), 1H nuclear magnetic resonance (1H NMR), thermogravimetric analysis (TGA), X-ray diffraction (XRD) and elemental analysis were conducted to characterize the successful synthesis of COS-O-Cin1-3. The results showed that they exhibited higher thermal stability, weaker crystallinity and better antibacterial properties than that of COS. These results aided in obtaining the important supports for exploring new functional antibacterial agents, which expand the scope of COS's application in the food industry.


Assuntos
Quitosana/química , Quitosana/farmacologia , Propanóis/química , Propanóis/farmacologia , Antibacterianos/análise , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Quitosana/análise , Quitosana/síntese química , Escherichia coli/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Propanóis/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/efeitos dos fármacos , Difração de Raios X
14.
Se Pu ; 37(10): 1048-1052, 2019 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-31642282

RESUMO

A method for the rapid screening of 1,3-dichloro-2-propanol, 2,3-dichloro-1-propanol,3-monochloropropane-1,2-diol, and 2-monochloropropane-1,3-diol in soy sauce was developed based on dispersive solid phase extraction-gas chromatography-high resolution mass spectrometry (GC-HRMS). The samples were extracted by ethyl acetate, cleaned up using N-propylethylenediamine and detected by GC-HRMS. The chloropropanols were quantified by the internal standard method. The results demonstrated that the limits of quantitation of the four chloropropanols were in the range of 0.5-10 µg/kg. The recoveries of the four chloropropanols in soy sauce spiked with three levels varied from 78% to 103%, and the relative standard deviations were no more than 8.8%. The proposed method is simple, accurate, sensitive and suitable for the rapid screening of the four chloropropanols in soy sauce.


Assuntos
Propanóis/análise , Alimentos de Soja/análise , Cromatografia Gasosa-Espectrometria de Massas , Extração em Fase Sólida
15.
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
16.
Food Chem ; 290: 263-269, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31000046

RESUMO

Blue mould caused by Penicillium expansum is one of the important diseases of apple fruit during storage. Phenylpropanoid pathway is an important induction mechanism that can utilize downstream metabolites of shikimate pathway to synthesize a series of secondary metabolites. Apple fruit (cv. Fuji) were treated with sodium nitroprusside (SNP) to study its effect on blue mould, shikimate and phenylpropanoid pathways. The results showed that 1.0 mmol L-1 SNP significantly inhibited lesion development of apple fruit inoculated with P. expansum. The results also indicated that SNP enhanced MdDHQS, MdSKDH, MdSK and MdEPSPS genes expressions, increased shikimic acid, tryptophan, tyrosine and phenylalanine contents in apple fruit. The activities of phenylalanine ammonialyase, 4-coumarate: coenzyme A, ligase, cinnamate 4-hydroxylase, lignin, total phenolic compounds and flavonoids contents in apple fruit were also increased by SNP treatment. These results suggest that SNP might modulate shikimate and phenylpropanoid pathways to enhance disease resistance of apple fruit.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Malus/química , Nitroprussiato/farmacologia , Propanóis/metabolismo , Ácido Chiquímico/metabolismo , Cromatografia Líquida de Alta Pressão , Frutas/química , Frutas/metabolismo , Malus/metabolismo , Fenóis/química , Fenóis/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Propanóis/análise , RNA de Plantas/isolamento & purificação , RNA de Plantas/metabolismo , Ácido Chiquímico/análise
17.
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
18.
Contact Dermatitis ; 80(6): 335-353, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30843216

RESUMO

In this article, contact allergy to Myroxylon pereirae resin (MP) (balsam of Peru) is reviewed. The topics presented include the uses, the chemical composition, the frequency of sensitization, the relevance of positive reactions, the MP-containing products causing allergic contact dermatitis, co-reactivity with other fragrance and non-fragrance materials, the sensitizers, the usefulness of MP as a "marker" of fragrance allergy, and the effectiveness of, and indications for, "balsam-restrictive" diets. Sensitization to MP occurs in 4% to 8% of patients routinely tested for suspected contact dermatitis. There are few adequate data on relevance. Topical pharmaceuticals were formerly, but are not today, important sources of sensitization. Cosmetics and foods or drinks are hardly ever products responsible for sensitization to MP. Positive patch test reactions in the large majority probably result from previous sensitization to MP constituents because of their presence in fragrances and fragranced products, MP thereby acting as marker (or "indicator") of fragrance allergy. However, fragrance mix I is a more sensitive marker, and the added diagnostic value of testing with MP is unknown. The allergenic ingredients of MP include isoeugenol, eugenol and cinnamyl alcohol, but there are other-largely unknown-chemicals that are responsible for contact allergy. Suggestions are given for further research to address questions thus far unanswered and to improve patient care.


Assuntos
Bálsamos/efeitos adversos , Dermatite Alérgica de Contato/diagnóstico , Dermatite Alérgica de Contato/prevenção & controle , Dieta , Testes do Emplastro , Bálsamos/química , Bálsamos/uso terapêutico , Bebidas/análise , Cosméticos/química , Reações Cruzadas , Dermatite Alérgica de Contato/etiologia , Eugenol/análogos & derivados , Eugenol/análise , Análise de Alimentos , Humanos , Perfumes/efeitos adversos , Perfumes/química , Preparações Farmacêuticas/química , Propanóis/análise
19.
J Perianesth Nurs ; 34(3): 606-613, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30665744

RESUMO

PURPOSE: Room ventilation in the postanesthesia care unit (PACU) is often poor, although patients exhale anesthetic gases. We investigated the PACU personnel's environmental and biological sevoflurane (SEVO) burden during patient care. DESIGN: Prospective, observational study. METHODS: Air pollution was measured by photoacoustic gas monitoring in the middle of the PACU, above the patient's face, and on the PACU corridor. Urinary SEVO and hexafluoroisopropanol concentrations were determined. FINDINGS: Mean air pollution was 0.34 ± 0.07 ppm in the middle of the PACU, 0.56 ± 0.17 ppm above the patient's face, and 0.47 ± 0.06 ppm on the corridor. Biological preshift exposure levels were 0.13 ± 0.03 mcg/L (SEVO) and 4.72 ± 5.41 mcg/L (hexafluoroisopropanol). Postshift concentrations increased significantly to 0.20 ± 0.06 mcg/L (P = .004) and 42.18 ± 27.82 mcg/L (P < .001). CONCLUSIONS: PACU personnel were environmentally and biologically exposed to SEVO, but exposure levels were minimal according to current recommendations.


Assuntos
Monitoramento Ambiental/métodos , Exposição Ocupacional/análise , Propanóis/análise , Sevoflurano/análise , Poluentes Ocupacionais do Ar/análise , Anestésicos Inalatórios/análise , Monitoramento Biológico/métodos , Feminino , Humanos , Masculino , Recursos Humanos em Hospital , Técnicas Fotoacústicas , Estudos Prospectivos , Sala de Recuperação
20.
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
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