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1.
Food Chem ; 441: 138320, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38199101

RESUMO

Polyphenol partitioning during mechanical (cold-pressing) and physiological (digestion) extraction at the individual polyphenol and subclass level was investigated. UHPLC-ESI-QTOF-MS/MS analysis yielded a comprehensive identification of 45 polyphenols whose semi-quantification revealed a hierarchical clustering strongly determined by polyphenol structure and their location within the apple tissue. For instance, pomace retained most flavonols and flavanols (degree of polymerization DP 5-7), which were highly hydrophobic, hydroxylated, or large (>434 Da), and more abundant in peel. In vitro digestion UHPLC-ESI-QTOF-MS/MS analysis of whole apple (and its corresponding matrix-free extract) clustered polyphenols into five main groups according to their interaction with plant cell walls (PCWs) during each digestion phase. This grouping was not reproduced in pomace, which exhibited a greater matrix effect than whole apple during oral and gastric digestion. Nevertheless, the interaction between most polyphenol groups, including dihydrochalcones, flavanols (DP 1-4) and hydroxycinnamic acid derivatives, and pomace PCWs was lost during intestinal digestion.


Assuntos
Malus , Polifenóis , Polifenóis/análise , Espectrometria de Massas em Tandem , Antioxidantes/análise , Extratos Vegetais/química , Análise por Conglomerados
2.
Nutrients ; 14(12)2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35745236

RESUMO

The raising consumer demand for plant-derived proteins has led to an increased production of alternative protein ingredients with varying processing histories. In this study, we used a commercially available potato protein ingredient with a nutritionally valuable amino acid profile and high technological functionality to evaluate if the digestibility of a suspension with the same composition is affected by differences in the structure. Four isocaloric (4% protein, w/w) matrices (suspension, gel, foam and heat-set foam) were prepared and their gastrointestinal fate was followed utilizing a semi-dynamic in vitro digestion model. The microstructure was observed by confocal laser scanning microscopy, protein breakdown was tested by electrophoresis and free amino acids after intestinal digestion was estimated using liquid chromatography/triple-quadruple-mass spectrometry (LC-TQMS). The heat-treated samples showed a higher degree of hydrolysis and lower trypsin inhibitory activity than the non-heat-treated samples. An in vitro digestible indispensable amino acid score was calculated based on experimental data, showing a value of 0.9 based on sulfur amino acids/valine as the limiting amino acids. The heated samples also showed a slower gastric emptying rate. The study highlights the effect of the food matrix on the distribution of the peptides created during various stages of gastric emptying.


Assuntos
Digestão , Solanum tuberosum , Aminoácidos/metabolismo , Trato Gastrointestinal/metabolismo , Humanos , Proteínas de Plantas/metabolismo , Solanum tuberosum/metabolismo
3.
Molecules ; 26(4)2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33546439

RESUMO

The rapid diffusion of new psychoactive substances (NPS) presents unprecedented challenges to both customs authorities and analytical laboratories involved in their detection and characterization. In this study an analytical approach to the identification and structural elucidation of a novel synthetic cannabimimetic, quinolin-8-yl-3-[(4,4-difluoropiperidin-1-yl) sulfonyl]-4-methylbenzoate (2F-QMPSB), detected in seized herbal material, is detailed. An acid precursor 4-methyl-3-(4,4-difluoro-1-piperidinylsulfonyl) benzoic acid (2F-MPSBA), has also been identified in the same seized material. After extraction from the herbal material the synthetic cannabimimetic, also referred to as synthetic cannabinoid receptor agonists or "synthetic cannabinoids", was characterized using gas chromatography-mass spectrometry (GC-MS), 1H, 13C, 19F and 15N nuclear magnetic resonance (NMR) and high-resolution tandem mass spectrometry (HR-MS/MS) combined with chromatographic separation. A cheminformatics platform was used to manage and interpret the analytical data from these techniques.


Assuntos
Canabinoides/análise , Drogas Ilícitas/análise , Ressonância Magnética Nuclear Biomolecular , Canabinoides/síntese química , Canabinoides/química , Europa (Continente) , Drogas Ilícitas/síntese química , Drogas Ilícitas/química , Espectrometria de Massas em Tandem
4.
Food Chem ; 347: 129040, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33484960

RESUMO

An Ultra High-Performance Liquid chromatography method quadruple time-of-flight mass spectrometry has been developed for the analysis of 11 cyclic polyesters oligomers, following a modified QuEChERS clean-up with alumina/primary secondary amine, in pasta. Target analytes were polyethylene terephthalate (PET) 1st series cyclic dimer to heptamer, polybutylene terephthalate (PBT) dimer to pentamer and a polyurethane oligomer. Standard addition method was applied for the calibration, and the limits of quantification ranged from 3.2 to 17.2 ng g-1. Recoveries ranged from 86.4 to 109.8%, RSDs were lower than 12% for all analytes, and matrix effect never exceeded ± 2.5%. The method was successfully applied to real commercial pasta samples, where the PET 1st series cyclic trimer was the most abundant oligomer, being found in all tested samples. The 1st series PET cyclic dimer and tetramer, as well as 1,4,7-trioxacyclotridecane-8,13-dione, were found in considerable amounts. Traces of the 2nd and 3rd series PET cyclic dimers were also found.


Assuntos
Análise de Alimentos/métodos , Espectrometria de Massas/métodos , Poliésteres/química , Polietilenotereftalatos/química , Óxido de Alumínio/química , Cromatografia Líquida de Alta Pressão , Dimerização , Farinha/análise , Poliésteres/análise , Polietilenotereftalatos/análise , Polimerização , Dióxido de Silício/química
5.
Food Chem ; 345: 128739, 2021 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-33333359

RESUMO

A HPLC-UV/FLD method was validated for the quantification of six polyethylene terephthalate (PET) and four polybutylene terephthalate (PBT) oligomers. PBT oligomers are EU regulated, while the PET ones are considered non-intentionally added substances (NIAS). LOQs were higher than 0.4 and 3.5 µg kg-1 for the simulants and in the polymer extracts, respectively. Recoveries ranged from 95 to 114 % with RSDs below 12%. Migration testing of PBT and polypropylene coffee capsules were performed with H2O and simulant C, and extracts were obtained with accelerated solvent extraction (ASE). For the latter legislative limits weren't surpassed. As no migration limits are existing for the analytes, both EFSA's toxicological threshold of concern (TTC) and sum of oligomers approaches were applied. The majority of oligomers were below the TTC (90 µg/person/day), but the limit value of 50 µg/kg food was surpassed for some capsules, which indicates a significant intake in both single and multiple consumption.


Assuntos
Café/química , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Embalagem de Alimentos , Poliésteres/análise , Polietilenotereftalatos/análise , Polimerização , Cromatografia Líquida de Alta Pressão , Ciclização , Poliésteres/química , Poliésteres/isolamento & purificação , Polietilenotereftalatos/química , Polietilenotereftalatos/isolamento & purificação
6.
Food Chem ; 317: 126427, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32092611

RESUMO

Determination of polyethylene terephthalate (PET) dimer up to heptamer 1st series cyclic oligomers, applying an LC-qTOF-MS method, has been developed and validated. Recoveries ranged between 80 and 112% with RSDs lower than 15%. An innovative semi-quantitative approach has been applied for 2nd and 3rd series cyclic oligomers, using the closest structural-similar 1st series cyclic oligomer standard as analytical reference. Oligomers from the three series were quantified in PET teabags after migration experiments with water and food simulants C (20% v/v ethanol in water) and D1 (50% v/v ethanol in water). No legal migration limits exist currently for these substances. In silico genotoxicity assessment of all identified oligomers has been performed and showed no genotoxicity alert for linear or cyclic molecules. Exposure assessment was performed using EFSA's approach on the total sum of migrating oligomers and on toxicological threshold-of-concern. Amounts found in water were in some cases significantly higher than the respective limits, especially in the worst-case scenario of multiple consumption.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Embalagem de Alimentos , Espectrometria de Massas/métodos , Polietilenotereftalatos/análise , Polietilenotereftalatos/toxicidade , Simulação por Computador , Dimerização , Contaminação de Alimentos/análise , Testes de Mutagenicidade , Polietilenotereftalatos/química , Reprodutibilidade dos Testes , Chá
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