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1.
Ecotoxicol Environ Saf ; 204: 111107, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32823057

RESUMO

Heavy metal pollution in marine environment poses a severe threat to the safety of marine products and is thus causing increasingly concerns in terms of their toxicity and potential health risks pose to human. Due to the complex matrix of marine products, a fast screening method for heavy metals at trace level with low price, reusability, high accuracy and long lifetime is of urgency and necessity for consumers and processing factories. This work described a simplified screening system through the preparation, characterization and particular application of Au nano particle sensor (AuNPS) in the complex marine matrix, the main aim is to significantly increase the stability, sensitivity and lifetime of detection system dedicated to Cu and Hg trace analysis in marine products. It is worth mentioning that, the proposed screening system was characterized through electrochemical experiments and theoretical calculations, which could be a new evidence for selecting the detection system in commercially complex samples. Importantly, the discipline of deposition and oxidative stripping process on AuNPS was explained based on the mechanism of Metal Ion Deficient Layer (MIDL), and illustrated with SEM changes during stripping process, as well as the dissolving-out rate of metals on AuNPS material. Moreover, to further improve the reusability and stability of AuNPS sensor, the complex marine matrix was purified by pre-plating interferences on indium tin oxide glass electrode. The screening system exhibited a liner response in the range of 0.02-0.10 µg mL-1 for Hg, 0.01-0.10 µg mL-1 and 0.001-0.01 µg mL-1 for Cu with the detection limits of 0.138 mg kg-1 and 1.51 mg kg-1 in marine matrix, respectively. The sensitivity and lifetime was at least two times better as compared to similar works even after 20-times use. Finally, this proposed analysis system combined with purification procedure was successfully applied for the edible and medicinal marine products analysis, meanwhile, the accuracy and stability were confirmed with standard analytical methods.


Assuntos
Análise de Alimentos/métodos , Nanopartículas Metálicas/química , Metais Pesados/análise , Eletrodos , Contaminação de Alimentos , Ouro/química , Humanos , Mercúrio/análise , Compostos de Estanho , Oligoelementos
2.
PLoS One ; 15(7): e0234899, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32645020

RESUMO

The increasing prevalence of individuals with multiple food allergies and the need to distinguish between foods containing homologous, cross-reactive proteins have made the use of single-analyte antibody-based methods (e.g., ELISAs) sometimes insufficient. These issues have resulted in the need to conduct multiple analyses and sometimes employ orthogonal methods like mass spectrometry or DNA-based methods for confirmatory purposes. The xMAP Food Allergen Detection Assay (xMAP FADA) was developed to solve this problem while also providing increased throughput and a modular design suitable for adapting to changes in analytical needs. The use of built-in redundancy provides the xMAP FADA with built-in confirmatory analytical capability by including complementary antibody bead sets and secondary analytical end points (e.g., ratio analysis and multi-antibody profiling). A measure of a method's utility is its performance when employed by analysts of varying expertise in multiple laboratory environments. To gauge this aspect, a multi-laboratory validation (MLV) was conducted with 11 participants of different levels of proficiency. The MLV entailed the analysis of incurred food samples in four problematic food matrices, meat sausage, orange juice, baked muffins, and dark chocolate. Except for a couple of instances, involving two confirmatory components in the analysis of baked muffins, the allergenic foods were detected by all participants at concentrations in the analytical samples comparable to ≤ 10 µg/g in the original food sample. In addition, despite high levels of inter-lab variance in the absolute intensities of the responses, the intra-laboratory reproducibility was sufficient to support analyses based on the calibration standards and direct comparison controls (DCCs) analyzed alongside the samples. In contrast, ratio analyses displayed inter-laboratory %CV (RSDR) values < 20%; presumably because the ratios are based on inherent properties of the antigenic elements. The excellent performance of the xMAP FADA when performed by analysts of varying proficiency indicates a reliability sufficient to meet analytical needs.


Assuntos
Ensaio de Imunoadsorção Enzimática/métodos , Hipersensibilidade Alimentar/diagnóstico , Hipersensibilidade Alimentar/imunologia , Alérgenos/imunologia , Anticorpos/imunologia , Bioensaio , Reações Cruzadas , Análise de Alimentos/métodos , Humanos , Laboratórios , Espectrometria de Massas , Reprodutibilidade dos Testes
3.
Food Chem ; 332: 127395, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32615385

RESUMO

This paper describes a simple, efficient and rapid analytical method for extraction and determination of nitrite in meat and chicken products by vortex-assisted supramolecular solvent-based liquid phase microextraction (VA-SUPRAS-LPME) prior to spectrophotometric detection. The SUPRAS was rapidly formed by the addition of a colloidal decanoic acid suspension to tetrahydrofuran (THF). The validation studies were carried out in terms of linearity, limit of detection (LOD), limit of quantitation (LOQ), matrix effects, robustness, uncertainty measurement, precision, accuracy, and certified reference material (CRM) analysis using optimized experimental conditions. The LOD, LOQ, linearity and matrix effect were 0.035 ng mL-1, 0.1 ng mL-1, 0.1-300 ng mL-1, and 9.6% respectively, with high preconcentration factor (200). The method was successfully applied for the determination of nitrite in processed products. Moreover, the results obtained by the proposed method were compared to the standard Griess method, and showed no significant differences in term of Student's t-test.


Assuntos
Galinhas , Análise de Alimentos/métodos , Microextração em Fase Líquida/métodos , Carne/análise , Nitritos/análise , Nitritos/isolamento & purificação , Solventes/química , Animais , Contaminação de Alimentos/análise , Manipulação de Alimentos , Química Verde , Humanos , Limite de Detecção , Espectrofotometria Ultravioleta
4.
Food Chem ; 332: 127392, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32623126

RESUMO

The present work describes a novel and rapid approach for evaluating total phenolic compounds (TPCs) in tea and fruits using colorimetric spots and the digital image-based (DIB) method. Colorimetric spots were formed by reacting diazotized aminobenzenes namely sulfanilic acid, sulfanilamide, or aniline with TPCs in the extract to form an azo dye. The limit of detection (LOD) was 6.5, 5.5, or 5.1 mg GAE (gallic acid equivalent) L-1 and the analytical range was 25-500, 20-500, or 18-200 mg GAE L-1, respectively. Correlation with the Folin-Ciocalteu assay was significant (Pearson coefficient, R = 0.970-0.991) while the antioxidant activity assay was moderate to high (R = 0.737-0.977). The method developed was successfully applied to the analysis of tea and fruits and showed RSD (n = 3) not exceeding 9.6, 8.5, and 9.7%, respectively. Ecologically, the DIB method developed could determine the variation of TPCs within cultivars and was found to be strongly dependent on the growing environment.


Assuntos
Benzeno/química , Colorimetria/métodos , Análise de Alimentos/métodos , Frutas/química , Fenóis/análise , Chá/química , Antioxidantes/análise , Limite de Detecção
5.
Food Chem ; 332: 127397, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32645675

RESUMO

Polyphosphates are permitted as food additives (Regulation EC No 1129/2011) but their undeclared utilisation is considered fraudulent. They improve water holding capacity of the seafood, preventing biochemical/physical changes during commercialization. The key objective of this study was the detection of polyphosphate in various seafood categories, by means of high-performance ion-exchange chromatography with suppressed conductometry (HPIEC-SCD) coupled to Q-Exactive Orbitrap high resolution mass spectrometry (HRMS-Orbitrap). Ten frozen cuttlefish samples did not reveal any treatment, while in ten frigate tunas, high concentration of orthophospate was found. Unambiguous hexametaphosphate presence was demonstrated in four prawn samples, while triphosphate was quantified (11.2 ± 4 ug/g) in another four prawn samples that contained orthophosphate (10225 ± 1102 ug/g), as well. Other samples sporadically encompassed polyphosphates profiles that varied according species and processing type. This analytical approach provided sustenance in better understanding regarding utilization of polyphosphates through HRMS fingerprinting of anionic species that would be specific in food safety control.


Assuntos
Aditivos Alimentares/análise , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Inocuidade dos Alimentos , Polifosfatos/análise , Alimentos Marinhos/análise , Animais , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Decapodiformes , Limite de Detecção , Espectrometria de Massas
6.
Food Chem ; 332: 127339, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32659697

RESUMO

Non-targeted NMR-based approach has received great attention as a rapid method for food product authenticity assessment. The availability of a database containing many comparable NMR spectra produced by different spectrometers is crucial to develop functional classifiers able to discriminate rapidly the commodity class of a given food product. Nevertheless, variability in spectrometer features may hamper the production of comparable spectra due to inherent variations in signal resolution. In this paper, we report on the development of a class-discrimination model for grape juice authentication by application of non-targeted NMR spectroscopy. Different approaches for the pre-treatment of data will be described along with details about the model validation. The developed model performed excellently (95.4-100% correct predictions) even when it was tested against 650 spectra produced by 65 spectrometers with different configurations (magnetic field strength, manufacturer, age). This study may boost the use of non-targeted NMR methods for food control.


Assuntos
Análise de Alimentos/métodos , Qualidade dos Alimentos , Campos Magnéticos , Espectroscopia de Ressonância Magnética/métodos , Bases de Dados Factuais , Sucos de Frutas e Vegetais/análise , Vitis/química
7.
Food Chem ; 333: 127447, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32688304

RESUMO

Quantification of the specific folate vitamers to estimate total folate in foods is not standardized. A collaborative study, including eight European laboratories, was conducted in order to determine the repeatability and reproducibility of the method for folate quantification in foods using the plant-origin γ-glutamyl hydrolase as part of the extraction procedure. The seven food samples analyzed represent the food groups; fruits, vegetables, dairy products, legumes, offal, fish, and fortified infant formula. The homogenization step was included, and six folate vitamers were analyzed using LC-MS/MS. Total folate content, expressed as folic acid equivalent, was 17-490 µg/100 g in all samples. Horwitz ratio values were within the acceptable range (0.60-1.94), except for fish. The results for fortified infant formula, a certified reference material (NIST 1869), confirmed the trueness of the method. The collaborative study is part of a standardization project within the Nordic Committee on Food Analysis (NMKL).


Assuntos
Fracionamento Químico/métodos , Ácido Fólico/análise , Análise de Alimentos/métodos , Espectrometria de Massas em Tandem/métodos , Animais , Cromatografia Líquida/métodos , Cromatografia Líquida/normas , Laticínios/análise , Grão Comestível/química , Produtos Pesqueiros/análise , Análise de Alimentos/normas , Alimentos Fortificados/análise , Frutas/química , Humanos , Lactente , Fórmulas Infantis/análise , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/normas , Verduras/química
8.
Food Chem ; 333: 127379, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32653678

RESUMO

The safety and regulatory status of fermented products derived from gluten-containing grains for patients with celiac disease remains controversial. Bottom-up mass spectrometry (MS) has complemented immunoassays for the compositional and immunogenic analyses of wheat beers. However, uncharacterized proteolysis during brewing followed by the secondary digestion for MS has made the analysis and data interpretation complicated. In this study, the composition and immunogenic potential of seven commercially available wheat beers were evaluated using bottom-up MS with the aid of fractionation and a multi-step peptide search strategy to identify peptides generated by various types of proteolysis. Gluten-derived peptides accounted for approximately 50% and 20% of the total number of wheat-derived and barley-derived peptides, respectively, in the investigated beers. Although relatively large polypeptides cannot be thoroughly characterized using traditional bottom-up proteomics, up to 50% of peptides identified contained celiac-immunogenic motifs, and consumption of wheat beers would pose risks for celiac patients.


Assuntos
Cerveja/análise , Análise de Alimentos/métodos , Espectrometria de Massas , Triticum/química , Triticum/imunologia , Fermentação , Glutens/química , Humanos , Peptídeos/análise , Peptídeos/imunologia
9.
Food Chem ; 333: 127421, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32653681

RESUMO

An extraction procedure was developed for the determination of aflatoxin M1 in milk and dairy products. A sorbent based on UVM-7 mesoporous silica was used as solid phase for the sample clean-up, and the analyte determination was carried out by HPLC coupled to a fluorescence detector. The material architecture was characterized by transmission electronic microscopy, X-ray diffraction, 29Si NMR and nitrogen adsorption-desorption. After the optimization of extraction parameters, the influence of the matrix has been evaluated, obtaining recoveries in the range 78-105% for whole and skimmed milk and yogurt matrix. The reusability of the material was also proved. The sensitivity of the method was also evaluated, and a LOQ (0.015 µg kg-1) below the European legislation limit was obtained. The procedure was successfully applied for the determination of aflatoxin M1 in real samples. The results were compared with those obtained with a reference method, being the results statistically comparable.


Assuntos
Aflatoxina M1/análise , Custos e Análise de Custo , Análise de Alimentos/métodos , Leite/química , Nanoestruturas/química , Dióxido de Silício/química , Iogurte/análise , Adsorção , Aflatoxina M1/química , Animais , Fluorescência , Análise de Alimentos/economia , Contaminação de Alimentos/análise , Limite de Detecção , Porosidade
10.
Food Chem ; 331: 127348, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-32619908

RESUMO

Information concerning food composition, including information on its glucose content, is essential for modern food industry due to greater consumer awareness and expectations. In this work, the gene encoding d-glucose dehydrogenase (GDH) from Bacillus Natto was expressed in Escherichia coli BL21(DE3) firstly. Ni-IDA column was used for the purification of GDH. Then, the purified GDH was used to construct a color system with stable and effective measurement of concentration of d-glucose. The smart phone photographing and the software Microsoft Photoshop have been used in the system for determination of the color. The enzymatic analysis system can detect the concentration of d-glucose from 5 mM to 40 mM, and other various sugars has no interference to the system. The system was used to quantitatively detect the concentration of d-glucose in honey. The system can be used for convenient and rapid detection of d-glucose in food, especially for large numbers of samples.


Assuntos
Análise de Alimentos/métodos , Glucose/análise , Mel/análise , Smartphone , Bacillus/genética , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Cor , Escherichia coli/genética , Análise de Alimentos/instrumentação , Glucose 1-Desidrogenase/genética , Glucose 1-Desidrogenase/metabolismo , Concentração de Íons de Hidrogênio , Limite de Detecção , Software
11.
Food Chem ; 331: 127361, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-32650229

RESUMO

A low cost hand-held spectral analytical system was developed for in situ screening of phenolics and flavonoids in puff dried Ziziphus jujuba (Z. Jujuba) samples. Standards of gallic acid, caffeic acid, l-epicatechin, phloridzin and cianidanol were used to quantify the individual phenolics and flavonoids using high performance liquid chromatography-diode array detector (HPLC-DAD). The synergy interval partial least square with ant colony optimization (Si-ACO-PLS) was attempted to optimize and capture informative variables for the prediction of target compounds. The model performance was evaluated using correlation coefficients of prediction (Rp); root mean square error of prediction (RMSEP) and residual predictive deviation (RPD). The Si-ACO-PLS yielded optimal performance, 0.8540 ≤ Rc ≤ 0.9250, 0.8360 ≤ Rp ≤ 0.9056, 0.84 ≤ RMSEP ≤ 16.30 and 2.03 ≤ RPD ≤ 2.26. The hand-held spectral analytical system coupled with Si-ACO-PLS proved to the reliable, rapid and cost-effective method to quantify the phenolics and flavonoids in Z. Jujuba.


Assuntos
Flavonoides/análise , Análise de Alimentos/instrumentação , Análise de Alimentos/métodos , Fenóis/análise , Ziziphus/química , Algoritmos , Cromatografia Líquida de Alta Pressão , Dessecação/métodos , Análise de Alimentos/estatística & dados numéricos , Análise dos Mínimos Quadrados , Análise Espectral/instrumentação , Análise Espectral/métodos
12.
Food Chem ; 333: 127439, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32653686

RESUMO

Anthocyanin is derived from a flavylium cation structure, and it promotes health in humans and functions in plants as protection against environmental stress. The rapid analysis of anthocyanin structure and content is a critical challenge for improving fruit quality. In this study, the tomato cultivar Indigo Rose, which is a popular purple cultivated tomato used for breeding, was taken as an example for anthocyanin analysis. A rapid analysis method was developed to minimize anthocyanin loss from the fresh fruit. Four new anthocyanins were discovered in the tomato, and the structures of a total of 12 anthocyanins were determined. Among these, petunidin-3-(trans-p-coumaroyl)-rutinoside-5-glucoside and malvidin-3-(trans-p-coumaroyl)-rutinoside-5-glucoside were the main anthocyanins in Indigo Rose. The structural modifications of these anthocyanins were mainly glycosylation and acylation, and there were also hydroxylation and methylation. Our findings provide new insight into the biosynthesis pathway in tomato fruit.


Assuntos
Antocianinas/análise , Antocianinas/química , Lycopersicon esculentum/química , Espectrometria de Massas/métodos , Acilação , Antocianinas/metabolismo , Cromatografia Líquida de Alta Pressão , Análise de Alimentos/métodos , Congelamento , Frutas/química , Glicosilação , Estrutura Molecular
13.
Food Chem ; 333: 127449, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32659663

RESUMO

The demand for the development of fast, easy-to-use and low-cost analytical methods for food adulteration analysis has being increasing in the last years. Although infrared spectroscopic techniques offer these advantages, the validation of screening methods requiring the application of multivariate data treatment is less frequently described in literature thus limiting their use as routine tools in control laboratories for food fraud monitoring. In this paper, an EU-validation procedure for screening methods was successfully applied to a multivariate FT-NIR spectroscopic method for the screening of durum wheat pasta samples adulterated with common wheat at the screening target concentration of 3%. Good results in terms of the cut-off value (2.32% mass fraction of soft wheat) and false suspect rates (0.1% for blanks; 13% at 1% mass fraction) demonstrated that the present validation approach would be a proof-of-strategy to be used for multivariate infrared methods applied for screening purposes.


Assuntos
Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Triticum/química , Farinha/análise , Análise de Alimentos/estatística & dados numéricos , Análise dos Mínimos Quadrados , Análise Multivariada , Espectroscopia de Luz Próxima ao Infravermelho/estatística & dados numéricos
14.
BMC Bioinformatics ; 21(1): 238, 2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32522154

RESUMO

BACKGROUND: Phytochemicals and other molecules in foods elicit positive health benefits, often by poorly established or unknown mechanisms. While there is a wealth of data on the biological and biophysical properties of drugs and therapeutic compounds, there is a notable lack of similar data for compounds commonly present in food. Computational methods for high-throughput identification of food compounds with specific biological effects, especially when accompanied by relevant food composition data, could enable more effective and more personalized dietary planning. We have created a machine learning-based tool (PhyteByte) to leverage existing pharmacological data to predict bioactivity across a comprehensive molecular database of foods and food compounds. RESULTS: PhyteByte uses a cheminformatic approach to structure-based activity prediction and applies it to uncover the putative bioactivity of food compounds. The tool takes an input protein target and develops a random forest classifier to predict the effect of an input molecule based on its molecular fingerprint, using structure and activity data available from the ChEMBL database. It then predicts the relevant bioactivity of a library of food compounds with known molecular structures from the FooDB database. The output is a list of food compounds with high confidence of eliciting relevant biological effects, along with their source foods and associated quantities in those foods, where available. Applying PhyteByte to the human PPARG gene, we identified irigenin, sesamin, fargesin, and delta-sanshool as putative agonists of PPARG, along with previously identified agonists of this important metabolic regulator. CONCLUSIONS: PhyteByte identifies food-based compounds that are predicted to interact with specific protein targets. The identified relationships can be used to prioritize food compounds for experimental or epidemiological follow-up and can contribute to the rapid development of precision approaches to new nutraceuticals as well as personalized dietary planning.


Assuntos
Análise de Alimentos/métodos , Compostos Fitoquímicos/química , Humanos
15.
Isotopes Environ Health Stud ; 56(4): 346-357, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32508164

RESUMO

Considering the increasing pet owner's concern about the food their pets are consuming, in this study we investigated the origin of the main ingredients in wet and dry foods produced in Brazil using stable isotope ratios of carbon and nitrogen. We concluded that chicken and pork seem to be the dominant ingredients in most of the samples, with larger proportions in wet cat food. Even in pet foods showing 'beef' as the main ingredient on the label, we found a low proportion of bovine products in both wet and dry cat foods. Comparing the contribution of plant-derived products (C3 and C4 plants) and animal-derived products (chicken-pork, bovine and fish), approximately 21 % of cat foods had more than 30 % of ingredients with plant origin in their composition. The high amount of plant-derived products in cat foods found here raises the question whether this should be mentioned on package labels.


Assuntos
Ração Animal/análise , Isótopos de Carbono/análise , Análise de Alimentos/métodos , Carne/análise , Isótopos de Nitrogênio/análise , Plantas/química , Animais , Brasil , Gatos , Bovinos , Galinhas , Peixes
16.
PLoS One ; 15(6): e0233745, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32542029

RESUMO

The susceptibility of newly expressed proteins to digestion by gastrointestinal proteases (e.g., pepsin) has long been regarded as one of the important endpoints in the weight-of-evidence (WOE) approach to assess the allergenic risk of genetically modified (GM) crops. The European Food Safety Authority (EFSA) has suggested that current digestion study protocols used for this assessment should be modified to more accurately reflect the diverse physiological conditions encountered in human populations and that the post-digestion analysis should include analytical methods to detect small peptide digestion products.The susceptibility of two allergens (beta-lactoglobin (ß-Lg) and alpha-lactalbumin (α-La)) and two non-allergens (hemoglobin (Hb) and phosphofructokinase (PFK)) to proteolytic degradation was investigated under two pepsin digestion conditions (optimal pepsin digestion condition: pH 1.2, 10 U pepsin/µg test protein; sub-optimal pepsin digestion condition: pH 5.0, 1 U pepsin/10 mg test protein), followed by 34.5 U trypsin/mg test protein and 0.4 U chymotrypsin/mg test protein digestion in the absence or presence of bile salts. All samples were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) in conjunction with Coomassie Blue staining and, in parallel, liquid chromatography tandem mass spectrometry (LC-MS) detection. The results provide following insights: 1) LC-MS methodology does provide the detection of small peptides; 2) Peptides are detected in both allergens and non-allergens from all digestion conditions; 3) No clear differences among the peptides detected from allergen and non-allergens; 4) The differences observed in SDS-PAGE between the optimal and sub-optimal pepsin digestion conditions are expected and align with kinetics and properties of the specific enzymes; 5) The new methodology with new digestion conditions and LC-MS detection does not provide any differentiating information for prediction whether a protein is an allergen. The classic pepsin resistance assay remains the most useful assessment of the potential exposure of an intact newly expressed protein as part of product safety assessment within a WOE approach.


Assuntos
Alérgenos/química , Análise de Alimentos/métodos , Peptídeos/química , Proteólise , Alérgenos/metabolismo , Animais , Cromatografia Líquida/métodos , Inocuidade dos Alimentos , Hemoglobinas/química , Hemoglobinas/metabolismo , Lactalbumina/química , Lactalbumina/metabolismo , Lactoglobulinas/química , Lactoglobulinas/metabolismo , Peptídeos/metabolismo , Fosfofrutoquinases/química , Fosfofrutoquinases/metabolismo , Suínos , Espectrometria de Massas em Tandem/métodos , Tripsina/metabolismo
17.
J Chromatogr A ; 1623: 461175, 2020 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-32505279

RESUMO

An ionic liquid hybrid zwitterionic polymer capillary microextraction (CME) column was prepared for the biomimetic enrichment of glycopeptides by one-step copolymerization of 2-methacryloyloxyethyl phosphorylcholine (MPC) and 1-butyl-3-vinylimidazolium bromide, in the presence of crosslinker trimethylolpropane trimethacrylate (TMA). The resultant monolith was characterized by scanning electron microscopy (SEM), fourier transform infrared (FT-IR) spectroscopy and pore size distribution measurement. Due to the incorporation of zwitterionic MPC owning a unique biomimic structure (i.e. hydrophilic cation/anion and hydrophobic long-alkyl chain), the monolithic column has large pore size and good biocompatibility, exhibiting high extraction efficiency, permeability and fast mass transfer to targets. Besides, the use of ionic liquids (ILs) as co-monomer in the polymerization endows the monolith with enhanced mechanical stability, uniformity and multiple interactions. The prepared column was successfully applied in CME coupled to capillary electrochromatography (CEC) for the efficient enrichment and separation of glycopeptide antibiotics in foodstuff. The method demonstrated a wide linear range (50.0-18000.0 µg L-1), low detection limits (5.0-10.0 µg L-1, S/N = 3) and satisfied recoveries (76.0-109.7%). This work shows the advantage of fine-tuning biomimetic monoliths in application-specific CME-CEC.


Assuntos
Antibacterianos/análise , Eletrocromatografia Capilar/métodos , Glicopeptídeos/análise , Líquidos Iônicos/química , Antibacterianos/isolamento & purificação , Materiais Biomiméticos , Fracionamento Químico , Análise de Alimentos/métodos , Glicopeptídeos/isolamento & purificação , Interações Hidrofóbicas e Hidrofílicas , Imidazóis/química , Metacrilatos/química , Microscopia Eletrônica de Varredura , Fosforilcolina/análogos & derivados , Fosforilcolina/química , Polimerização , Polímeros/química , Espectroscopia de Infravermelho com Transformada de Fourier , Compostos de Vinila/química
18.
Food Chem ; 330: 127266, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32540528

RESUMO

The present study aimed to characterize the nutritional value and potential use of elderberries as a source of antioxidant compounds. The chemical composition, fatty acids and phenolic compounds were determined for elderberries. The optimization of extraction parameters was designed with a Box-Behnken design coupled with response surface methodology (RSM) and desirability function analysis. The process parameters tested included extraction temperature, % of ethanol and pH, while response variables were global extraction yield, total phenolic and anthocyanins content (TAC), carotenoids and antioxidant activity. Analyses revealed that elderberry was a rich source of total soluble solids, proteins and polyunsaturated fatty acids (omega-3: 38.12 g/100 g and omega-6: 39.54 g/100 g fatty acids). Regarding phenolic compounds, elderberries were found abundant in flavonoids (rutin and quercetin), and phenolic acids (i.e. gallic acid and gentisic acid). Finally, numerical optimization indicated that the best extraction parameters were the following: temperature 60 °C, 50% of ethanol and pH 2.


Assuntos
Antioxidantes/análise , Antioxidantes/química , Sambucus nigra/química , Antocianinas/análise , Carotenoides/análise , Fracionamento Químico , Etanol/química , Flavonoides/análise , Análise de Alimentos/métodos , Ácido Gálico/análise , Concentração de Íons de Hidrogênio , Hidroxibenzoatos/análise , Valor Nutritivo , Fenóis/análise , Extratos Vegetais/química , Quercetina/análise , Solventes , Espectrometria de Massas em Tandem , Temperatura
19.
Food Chem ; 330: 127317, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32569934

RESUMO

Fermentation may enhance the nutritional properties of foods by increasing metabolite bioactivity or bioavailability. This study explored the effect of fermentation on isoflavone bioavailability and metabolism. Isoflavone metabolites were tracked in foods and biospecimens of healthy adults after fermented soybean (FS) or non-fermented soybean (NFS) consumption in a randomized, controlled, crossover intervention study. The change in soybean isoflavones caused by fermentation resulted in faster absorption and higher bioavailability after consumption of FS. Although the urinary level of total isoflavone metabolites was similar after the consumption of the two diets, urinary genistein 7-O-sulfate was derived as a discriminant metabolite for the FS diet by partial least squares discriminant analysis. This study suggests that an isoflavone conjugate profile might be a more appropriate marker than total isoflavone levels for discriminating between the consumption of FS and NFS diets.


Assuntos
Análise de Alimentos/métodos , Isoflavonas/análise , Isoflavonas/farmacocinética , Soja/metabolismo , Adulto , Disponibilidade Biológica , Dieta , Feminino , Alimentos e Bebidas Fermentados , Genisteína/metabolismo , Humanos , Isoflavonas/sangue , Isoflavonas/urina , Masculino , Pessoa de Meia-Idade
20.
Food Chem ; 330: 127330, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32569941

RESUMO

Conventional analysis, electronic senses and HS-SPME-GC-MS were applied to evaluate the effects of pretreatment methods and leaching methods on jujube wine quality. Significant differences (p < 0.05) in the levels of alcohol content, color, taste and aroma were observed among all the jujube wine samples, in which the pulp and pectase fermented jujube wine was the best among all. Moreover, rather than taste, aroma is the most significantly (p < 0.05) affected. In regard to aroma, a total of 182 volatile compounds were identified by HS-SPME-GC-MS. It was found that the blended-into-pulp treatment and the leached-by-pectase treatment had notable positive effects on jujube wine. The pulp and pectase fermented jujube wines exhibited the highest concentration of total volatile compounds as well as alcohols, esters, acids and aldehydes. Thus, the optimal pretreatment method and leaching method for jujube wine fermentation are blended-into-pulp and leached-by-pectase respectively.


Assuntos
Análise de Alimentos/métodos , Qualidade dos Alimentos , Vinho/análise , Ziziphus , Álcoois/análise , Aldeídos/análise , Cor , Nariz Eletrônico , Ésteres/análise , Fermentação , Análise de Alimentos/estatística & dados numéricos , Frutas/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Análise Multivariada , Odorantes/análise , Microextração em Fase Sólida/métodos , Paladar , Compostos Orgânicos Voláteis/análise , Ziziphus/química
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