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1.
Molecules ; 29(9)2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38731577

RESUMO

Recently, benchtop nuclear magnetic resonance (NMR) spectrometers utilizing permanent magnets have emerged as versatile tools with applications across various fields, including food and pharmaceuticals. Their efficacy is further enhanced when coupled with chemometric methods. This study presents an innovative approach to leveraging a compact benchtop NMR spectrometer coupled with chemometrics for screening honey-based food supplements adulterated with active pharmaceutical ingredients. Initially, fifty samples seized by French customs were analyzed using a 60 MHz benchtop spectrometer. The investigation unveiled the presence of tadalafil in 37 samples, sildenafil in 5 samples, and a combination of flibanserin with tadalafil in 1 sample. After conducting comprehensive qualitative and quantitative characterization of the samples, we propose a chemometric workflow to provide an efficient screening of honey samples using the NMR dataset. This pipeline, utilizing partial least squares discriminant analysis (PLS-DA) models, enables the classification of samples as either adulterated or non-adulterated, as well as the identification of the presence of tadalafil or sildenafil. Additionally, PLS regression models are employed to predict the quantitative content of these adulterants. Through blind analysis, this workflow allows for the detection and quantification of adulterants in these honey supplements.


Assuntos
Suplementos Nutricionais , Mel , Espectroscopia de Ressonância Magnética , Mel/análise , Suplementos Nutricionais/análise , Espectroscopia de Ressonância Magnética/métodos , Citrato de Sildenafila/análise , Fluxo de Trabalho , Quimiometria/métodos , Tadalafila/análise , Análise dos Mínimos Quadrados , Contaminação de Medicamentos/prevenção & controle , Análise Discriminante
2.
Magn Reson Chem ; 62(5): 328-336, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37736944

RESUMO

Omega-3 fatty acid supplements, such as fish oil and plant-based oils, have gained popularity because of their potential health benefits. However, the quality and composition of these supplements can vary widely, particularly in terms of the two main forms of omega-3 fatty acids: triacylglycerols (TAGs) and ethyl esters (EEs). TAGs are the natural form found in fish oil but are prone to oxidation, whereas EEs are more stable but less well absorbed by the body. Differentiating between these forms is crucial for assessing the efficacy and tolerance of omega-3 supplements. This article describes a novel approach to differentiate between TAG and EE forms of omega-3 fatty acids in dietary supplements, utilizing a 60-MHz benchtop nuclear magnetic resonance (NMR) spectrometer. The proposed method using 1H and 1H-1H COSY NMR provides a quick and accurate approach to screen the forms of omega-3 fatty acids and evaluate their ratios. The presence of diacylglycerol (DAGs) in some supplements was also highlighted by this method and adds some information about the process used (i.e., esterification/enrichment). The affordability and user-friendliness of benchtop NMR equipment make this method feasible for food processing companies or quality control laboratories. In this study, 24 oil supplements were analyzed using NMR analysis in order to demonstrate the potential of this method for the differentiation of TAG and EE forms in omega-3 supplements.


Assuntos
Ácidos Graxos Ômega-3 , Ácidos Graxos , Ácidos Graxos Ômega-3/química , Óleos de Peixe/química , Suplementos Nutricionais/análise , Espectroscopia de Ressonância Magnética
3.
Food Res Int ; 165: 112473, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36869486

RESUMO

We investigated the possibility to use rapeseed as a main oil in ice cream formulations by changing its functionality when using different kinds of lipases. Through a 24 h-emulsification and a centrifugation, the modified oils were further used as functional ingredients. All lipolysis was first assessed as a function of time by 13C NMR, where triglycerides consumption and the formation of low-molecular polar lipids (LMPL: monoacylglycerol and free fatty acids, FFAs) were selectively identified and compared. The more the FFAs, the sooner the crystallization (from -55 to -10 °C) and the later the melting temperatures (from -17 to 6 °C) measured by differential scanning calorimetry. These modifications were exploited in ice cream formulations with a significant impact on overall hardness (range of 60-216 N) and flowing during defrosting (from 1.29 to 0.35g/min). The global behavior of products can be controlled by the composition of LMPL within oil.


Assuntos
Brassica napus , Sorvetes , Óleo de Brassica napus , Cristalização , Lipase , Ácidos Graxos não Esterificados
4.
J Pharm Biomed Anal ; 227: 115283, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36780864

RESUMO

Ten POWER dietary supplements, chronologically called tabs, pills then caps, and advertised as 100% natural aphrodisiacs, were analyzed by 1H NMR from 2007 to 2022. They were all tainted by PDE-5 inhibitors. Eight different adulterants were identified (sildenafil (1), sildenafil analogues (6), and vardenafil analogue (1)). Their amounts ranged from 15 to 145 mg/capsule. Four supplements contained at least 100 mg/capsule of PDE-5 inhibitor or analogue, the maximal recommended dose of sildenafil. The nature of the adulterant has changed over time, probably to evade its detection by regulatory agencies routine screening tests. Despite several warnings and/or seizures from several European food and/or health authorities, the dietary supplement POWER is still on sale on the Internet, thus demonstrating the impossibility of controlling this market. Faced with this situation, the consumer should be better informed by establishing at the European level a public database of tainted dietary supplements on the model of that of the US Food and Drug Administration. It should indicate the product name, its photo, the adulterant name, and be easily accessible to everyone.


Assuntos
Suplementos Nutricionais , Inibidores da Fosfodiesterase 5 , Suplementos Nutricionais/análise , Contaminação de Medicamentos/prevenção & controle , Espectroscopia de Ressonância Magnética , Inibidores da Fosfodiesterase 5/farmacologia , Citrato de Sildenafila , Dicloridrato de Vardenafila , Humanos
5.
Transl Res ; 251: 2-13, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35724933

RESUMO

Calcium accumulation in atherosclerotic plaques predicts cardiovascular mortality, but the mechanisms responsible for plaque calcification and how calcification impacts plaque stability remain debated. Tissue-nonspecific alkaline phosphatase (TNAP) recently emerged as a promising therapeutic target to block cardiovascular calcification. In this study, we sought to investigate the effect of the recently developed TNAP inhibitor SBI-425 on atherosclerosis plaque calcification and progression. TNAP levels were investigated in ApoE-deficient mice fed a high-fat diet from 10 weeks of age and in plaques from the human ECLAGEN biocollection (101 calcified and 14 non-calcified carotid plaques). TNAP was inhibited in mice using SBI-425 administered from 10 to 25 weeks of age, and in human vascular smooth muscle cells (VSMCs) with MLS-0038949. Plaque calcification was imaged in vivo with 18F-NaF-PET/CT, ex vivo with osteosense, and in vitro with alizarin red. Bone architecture was determined with µCT. TNAP activation preceded and predicted calcification in human and mouse plaques, and TNAP inhibition prevented calcification in human VSMCs and in ApoE-deficient mice. More unexpectedly, TNAP inhibition reduced the blood levels of cholesterol and triglycerides, and protected mice from atherosclerosis, without impacting the skeletal architecture. Metabolomics analysis of liver extracts identified phosphocholine as a substrate of liver TNAP, who's decreased dephosphorylation upon TNAP inhibition likely reduced the release of cholesterol and triglycerides into the blood. Systemic inhibition of TNAP protects from atherosclerosis, by ameliorating dyslipidemia, and preventing plaque calcification.


Assuntos
Aterosclerose , Calcinose , Dislipidemias , Placa Aterosclerótica , Camundongos , Humanos , Animais , Fosfatase Alcalina , Músculo Liso Vascular , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Aterosclerose/etiologia , Aterosclerose/prevenção & controle , Apolipoproteínas E , Triglicerídeos
6.
Macromol Rapid Commun ; 44(4): e2200729, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36443826

RESUMO

Photo-iniferter reversible addition-fragmentation chain transfer (PI-RAFT) polymerization of N-vinylformamide (NVF) is demonstrated by using purple light. PNVFs with predetermined molar masses and narrow molar mass distributions are obtained. High RAFT chain-end fidelity is confirmed by matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) and electrospray-ionization time-of-flight mass spectrometry (ESI-TOF-MS), and chain extension experiment. To demonstrate the potential of this approach, an original poly(N-vinylpyrrolidone)-b-poly(N-vinylformamide) (PVP-b-PNVF) diblock copolymer is synthesized and characterized by aqueous size-exclusion chromatography (SEC), asymmetric flow field-flow fractionation (A4F), and 1 H diffusion-ordered spectroscopy nuclear magnetic resonance (1 H DOSY NMR). Finally, selective hydrolysis of PNVF block to corresponding pH-responsive poly(N-vinylpyrrolidone)-b-poly(N-vinylformamide) (PVP-b-PVAm) is performed.


Assuntos
Polivinil , Polimerização , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
7.
J Pharm Biomed Anal ; 223: 115161, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36402125

RESUMO

Due to their health benefits, including regulating blood sugar and lowering cholesterol, berberine food supplements (FS) are widely used by consumers. This study aims to evaluate the quality of such products by proposing a new analytical methodology based on low-field NMR. Eighteen berberine FS were analyzed with both conventional (500 MHz) and benchtop (60 MHz) NMR spectrometers. Three quantitative 60 MHz 1H NMR methodologies were performed to determine berberine contents that were compared to those obtained at 500 MHz considered as reference measurements. To make the recording time of the spectra acquired at low field compatible with the requirements of a routine control, the quantification was carried out using a calibration curve established under conditions of incomplete relaxation of BrB protons. This methodology, applied to a test sample of 15 mg of FS, allowed to accurately measure a minimum quantity of berberine of ≈ 10 mg/capsule or tablet in 15 min. Regarding the FS, their labels are often unclear and/or incomplete for the consumer. Moreover, only 56 % of the FS analyzed actually contain the claimed quantity of berberine. The amounts of active they supply per day are extremely variable with only 39 % of the FS delivering a sufficient dose to achieve a hypoglycemic or hypolipidemic effect (1000-1500 mg/day based on literature data). These results show that health authorities should institute much stricter control and regulation over the production, labeling and marketing of berberine-based FS.


Assuntos
Berberina , Prótons , Espectroscopia de Prótons por Ressonância Magnética , Imageamento por Ressonância Magnética , Suplementos Nutricionais
8.
Electrophoresis ; 44(3-4): 431-441, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36398472

RESUMO

Ammonium perfluorooctanoate (APFOA) was used as a surfactant for the separation of free unsaturated C18 fatty acids by micellar electrokinetic chromatography. A simple background electrolyte of 50 mM APFOA water/methanol (90:10, v/v) at pH = 10 enabled the repeatable separation of oleic acid, elaidic acid, linoleic acid, and alpha-linolenic acid in less than 20 min. Separation conditions were optimized regarding various parameters (organic solvent, counterion, APFOA concentration, and pH). Because the repulsive interactions between fluorocarbon chains and hydrogenated chains are known to lead to segregation and phase separation, the choice of perfluorinated micelles to separate such perhydrogenated long-chain acids could appear astonishing. Therefore, the critical micelle concentration, the charge density, and the mobility of the micelles have been determined, resulting in a first description of the separation process.


Assuntos
Cromatografia Capilar Eletrocinética Micelar , Micelas , Cromatografia Capilar Eletrocinética Micelar/métodos , Tensoativos/química , Caprilatos
9.
J Pharm Biomed Anal ; 212: 114631, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35231794

RESUMO

Due to the numerous potential health benefits of Curcuma, turmeric dietary supplements (DS) are among the top selling products. To assess the quality of these formulations, thirty Curcuma DS along with five standard Curcuma rhizomes were analyzed with UHPLC-MS and 1H NMR. The chemometric treatment of the UHPLC-MS spectra showed a significant variability of their chemical composition that was confirmed by 1H NMR which allowed the absolute quantification of the Curcuma major bioactive components, i.e. curcuminoids (curcumin, demethoxycurcumin and bisdemethoxycurcumin), and turmerones (aryl-, α- and ß-) as well as piperine, a commonly associated curcumin bioavailability enhancer: respectively 3.5-556, 0-8.6, 0.18-8.1 mg/capsule or tablet. The comparison of the actual and claimed quantities of curcuminoids and piperine showed that 58% of the DS contained the expected amounts of actives.


Assuntos
Curcuma , Curcumina , Cromatografia Líquida , Curcuma/química , Curcumina/análise , Diarileptanoides , Suplementos Nutricionais/análise , Extratos Vegetais/química , Espectroscopia de Prótons por Ressonância Magnética , Espectrometria de Massas em Tandem
10.
Food Chem ; 369: 130870, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34455323

RESUMO

Commercial oleogelators rich in monoglycerides (MGs) are complex mixtures of acylglycerides with variable gelling properties, depending on the oil used and their concentration. In this study we developed a chemometric approach to identify the key parameters involved in gelling process. Analytical parameters have been defined, using GC and NMR analysis to identify fatty acids and acylglycerides composing the mixtures. Specific acylglyceride families and compound ratios were calculated to streamline the analytical results. To determine the key analytical parameters, artificial neural networks were used in a QSPR study related to the gelling properties measured by rheology through oscillatory experiments. At low oleogelator concentrations, the MGs especially rich in C16:0 and the ratio of specific isomers both have a positive influence on G'. For high oleogelator concentrations, C18:0-rich acylglycerides and unsaturated/saturated fatty acid ratios have a positive influence on G'. Conversely, at low concentrations, C18:0-rich acylglycerides show a lesser effect on G'.


Assuntos
Ácidos Graxos Insaturados , Monoglicerídeos , Ácidos Graxos , Humanos , Óleo de Brassica napus , Reologia
11.
Clin Kidney J ; 14(12): 2490-2496, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34950461

RESUMO

BACKGROUND: Down-regulation of the enzymes involved in tryptophan-derived nicotinamide (NAM) adenine dinucleotide (NAD+) production was identified after acute kidney injury (AKI), leading to the hypothesis that supplementation with NAM may increase the kidney NAD+ content, rescuing tryptophan pathways and subsequently improving kidney outcomes. METHODS: Urinary measurement of tryptophan and kynurenin using liquid chromatography-mass spectrometry metabolomics was used in a cohort of 167 cardiac bypass surgery patients along with tests for correlation to the development of postoperative AKI. A mouse model of ischaemic AKI using ischaemia-reperfusion injury (bilateral clamping of renal arteries for 25 min) was also used. RESULTS: We identified a significant decrease in urinary tryptophan and kynurenin in patients developing AKI, irrespective of the Kidney Disease: Improving Global Outcomes (KDIGO) stage. Although a significant difference was observed, tryptophan and kynurenin moderately discriminated for the development of all AKI KDIGO stages {area under the curve [AUC] 0.82 [95% confidence interval (CI) 0.75-0.88] and 0.75 [0.68-0.83], respectively} and severe KDIGO Stages 2-3 AKI [AUC 0.71 (95% CI 0.6-0.81) and 0.66 (0.55-0.77), respectively]. Sparked by this confirmation in humans, we aimed to confirm the potential preventive effect of NAM supplementation in wild-type male and female C57BL/6 mice subjected to ischaemic AKI. NAM supplementation had no effect on renal function (blood urea nitrogen at Day 1, sinistrin-fluorescein isothiocyanate glomerular filtration rate), architecture (periodic acid-Schiff staining) and injury or inflammation (kidney injury molecule 1 and IL18 messenger RNA expression). In addition, NAM supplementation did not increase post-AKI NAD+ kidney content. CONCLUSION: Notwithstanding the potential role of NAM supplementation in the setting of basal NAD+ deficiency, our findings in mice and the reanalysis of published data do not confirm that NAM supplementation can actually improve renal outcomes after ischaemic AKI in unselected animals and probably patients.

12.
FASEB J ; 35(11): e21931, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34653285

RESUMO

Energetic metabolism controls key steps of kidney development, homeostasis, and epithelial repair following acute kidney injury (AKI). Hepatocyte nuclear factor-1ß (HNF-1ß) is a master transcription factor that controls mitochondrial function in proximal tubule (PT) cells. Patients with HNF1B pathogenic variant display a wide range of kidney developmental abnormalities and progressive kidney fibrosis. Characterizing the metabolic changes in PT cells with HNF-1ß deficiency may help to identify new targetable molecular hubs involved in HNF1B-related kidney phenotypes and AKI. Here, we combined 1 H-NMR-based metabolomic analysis in a murine PT cell line with CrispR/Cas9-induced Hnf1b invalidation (Hnf1b-/- ), clustering analysis, targeted metabolic assays, and datamining of published RNA-seq and ChIP-seq dataset to identify the role of HNF-1ß in metabolism. Hnf1b-/- cells grown in normoxic conditions display intracellular ATP depletion, increased cytosolic lactate concentration, increased lipid droplet content, failure to use pyruvate for energetic purposes, increased levels of tricarboxylic acid (TCA) cycle intermediates and oxidized glutathione, and a reduction of TCA cycle byproducts, all features consistent with mitochondrial dysfunction and an irreversible switch toward glycolysis. Unsupervised clustering analysis showed that Hnf1b-/- cells mimic a hypoxic signature and that they cannot furthermore increase glycolysis-dependent energetic supply during hypoxic challenge. Metabolome analysis also showed alteration of phospholipid biosynthesis in Hnf1b-/- cells leading to the identification of Chka, the gene coding for choline kinase α, as a new putative target of HNF-1ß. HNF-1ß shapes the energetic metabolism of PT cells and HNF1B deficiency in patients could lead to a hypoxia-like metabolic state precluding further adaptation to ATP depletion following AKI.


Assuntos
Células Epiteliais/metabolismo , Deleção de Genes , Glicólise/genética , Fator 1-beta Nuclear de Hepatócito/metabolismo , Homeostase/genética , Túbulos Renais Proximais/citologia , Transdução de Sinais/genética , Injúria Renal Aguda/metabolismo , Animais , Sistemas CRISPR-Cas , Hipóxia Celular/genética , Linhagem Celular , Proliferação de Células/genética , Sobrevivência Celular/genética , Regulação da Expressão Gênica , Técnicas de Inativação de Genes/métodos , Fator 1-beta Nuclear de Hepatócito/genética , Humanos , Metaboloma , Camundongos , Transcriptoma
13.
Forensic Sci Int ; 324: 110813, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33993010

RESUMO

The 1H NMR profiles of 13 samples of e-liquids supplied by French customs were obtained with high-field and low-field NMR. The high-field 1H NMR spectra allowed the detection of matrix signals, synthetic cannabinoids, and flavouring compounds. Quantitative results were obtained for the five synthetic cannabinoids detected: JWH-210, 5F-MDMB-PICA, 5F-ADB, 5F-AKB48, and ADB-FUBINACA. Conventional GC-MS analysis was used to confirm compound identification. Fluorine-19 NMR was proposed for the quantification of fluorinated synthetic cannabinoids and was successfully implemented on both 400 MHz and 60 MHz NMR spectrometers. This study based on few examples explored the potentiality of low-field NMR for quantitative and quantitative analysis of synthetic cannabinoids in e-liquids.


Assuntos
Canabinoides/análise , Sistemas Eletrônicos de Liberação de Nicotina , Espectroscopia de Ressonância Magnética/métodos , Flúor , Cromatografia Gasosa-Espectrometria de Massas , Humanos
14.
Anal Chim Acta ; 1152: 338284, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33648641

RESUMO

The study of organic matter in wastewater is a major regulatory and environmental issue and requires new developments to identify non-biodegradable refractory compounds, produced mainly by thermal treatments. Recent advances linking physicochemical properties to spectroscopic analyzes (UV, Fluorescence, IR) have shown that the refractory property is favored by several physicochemical parameters: weight, hydrophobicity, aromaticity and chemical functions. Currently, the most effective developments for the quantification of refractory compounds are obtained with hyphenated methods, based on steric separation of the macromolecular species by steric exclusion chromatography (SEC)/PDA/Fluorescence systems. Hyphenated techniques using High Resolution Mass Spectrometry (HRMS), ultra-high-resolution mass spectrometry with Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR MS) and NMR have been developed to analyze macromolecules in wastewater with minor sample preparation procedures. A particular class has been identified, the melanoidins, generated by Maillard reactions between sugars, amino acids, peptides and proteins present in wastewater and sludge, but low molecular weight compounds formed as intermediates, such as ketones, aldehydes, pyrazines, pyridines or furans, are also recalcitrant and are complex to identify in the complex matrices. The lack of available standards for the study of these compounds requires the use of specific techniques and data processing. Advances in chemometrics are obtained in the development of molecular or physicochemical indices resulting from the data generated by the analytical detectors, such as aromaticity calculated by SUVA254 and determined by UV, fluorescence, molar mass, H/C ratio or structural studies (measuring the amount of unsaturated carbon) given by hyphenated techniques with SEC. It is clear that nitrogen compounds are widely involved in refractoriness. New trends in nitrogen containing compounds characterization follow two axes: through SEC/PDA/Fluorescence and HRMS/NMR techniques with or without separation. Other techniques widely used in food or marine science are also being imported to this study, as it can be seen in the use of "omics" methods, high-performance thin layer chromatography (HPTLC) and chromatography at the critical condition, rounding out the important developments around SEC. While improving the performance of stationary phases is one of the challenges, it results in a fundamental understanding of the retention mechanisms that today provide us with more information on the structures identified. The main objective of this review is to present the spectroscopic and physicochemical techniques used to qualify and characterize refractoriness with a specific focus on chemometric approaches.


Assuntos
Esgotos , Águas Residuárias , Cromatografia em Gel , Espectrometria de Massas
15.
J Pharm Biomed Anal ; 191: 113482, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-32898728

RESUMO

A sexual enhancer dietary supplement in pre-commercialization phase was analyzed. It contained the two phosphodiesterase-5 inhibitors (PDE-5i) sildenafil and methisosildenafil as major adulterants. Fourteen more sildenafil derivatives were detected and after isolation, their structures were elucidated thanks to NMR, high resolution and tandem mass spectrometry, and UV spectroscopy. Ten of them were never described. All these compounds are probably by-products of different reaction steps during the synthesis of the two PDE-5i that were not properly eliminated during the purification procedure. The total amount of sildenafil-related compounds was estimated at 68 mg per capsule, sildenafil and methisosildenafil accounting for 20 mg and 38 mg respectively.


Assuntos
Contaminação de Medicamentos , Inibidores da Fosfodiesterase 5 , Suplementos Nutricionais/análise , Citrato de Sildenafila , Espectrometria de Massas em Tandem
16.
Molecules ; 25(5)2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-32155779

RESUMO

The recent introduction of compact or low-field (LF) NMR spectrometers that use permanent magnets, giving rise to proton (1H) NMR frequencies between 40 and 80 MHz, have opened up new areas of application. The two main limitations of the technique are its insensitivity and poor spectral resolution. However, this study demonstrates that the chemometric treatment of LF 1H NMR spectral data is suitable for unveiling medicines as adulterants of slimming dietary supplements (DS). To this aim, 66 DS were analyzed with LF 1H NMR after quick and easy sample preparation. A first PLS-DA model built with the LF 1H NMR spectra from forty DS belonging to two classes of weight-loss DS (non-adulterated, and sibutramine or phenolphthalein-adulterated) led to the classification of 13 newly purchased test samples as natural, adulterated or borderline. This classification was further refined when the model was made from the same 40 DS now considered as representing three classes of DS (non-adulterated, sibutramine-adulterated, and phenolphthalein-adulterated). The adulterant (sibutramine or phenolphthalein) was correctly predicted as confirmed by the examination of the 1H NMR spectra. A limitation of the chemometric approach is discussed with the example of two atypical weight-loss DS containing fluoxetine or raspberry ketone.


Assuntos
Suplementos Nutricionais/análise , Contaminação de Medicamentos , Espectroscopia de Prótons por Ressonância Magnética , Suplementos Nutricionais/normas , Espectroscopia de Prótons por Ressonância Magnética/métodos
17.
Molecules ; 25(2)2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31941089

RESUMO

Red yeast rice dietary supplements (RYR DS) are largely sold in Western countries for their cholesterol-lowering/regulating effect due to monacolins, mainly monacolin K (MK), which is, in fact, lovastatin, the first statin drug on the market. 1H-NMR was used as an easy, rapid and accurate method to establish the chemical profiles of 31 RYR DS and to quantify their monacolin contents. Among all the 1H resonances of the monacolins found in RYR, only those of the ethylenic protons of the hexahydronaphthalenic ring at 5.84 and 5.56 ppm are suitable for quantification because they show no overlap with the matrix signals. The total content in monacolins per capsule or tablet determined in 28 DS (the content in 3 DS being below the limit of quantification of the method, ≈ 0.25 mg per unit dose) was close to that measured by UHPLC, as shown by the good linear correlation between the two sets of values (slope 1.00, y-intercept 0.113, r2 0.986). Thirteen of the 31 RYR DS analyzed (i.e., 42%) did not provide label information on the concentration of monacolins and only nine of the 18 formulations with an indication (i.e., 50%) actually contained the declared amount of monacolins.


Assuntos
Produtos Biológicos/análise , Suplementos Nutricionais/análise , Naftalenos/análise , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas , Ressonância Magnética Nuclear Biomolecular
18.
Talanta ; 202: 572-579, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31171223

RESUMO

Bladder cancer (BCa) is ninth amongst the most common types of cancer in the human population worldwide. The statistics of incidence and mortality of BCa are alarming and the currently applied diagnostic methods are still not sensitive enough. This leads to a large number of undiagnosed BCa cases, usually among patients in the early stages of the disease. Despite the fact that many risk factors of BCa have been recognized, the pathomechanism of development of bladder cancer has not been fully explained yet. Therefore, in the present study, multiplatform urinary metabolomics has been implemented in order to scrutinize potential diagnostic indicators of BCa that might help to explain its pathomechanism and be potentially useful in diagnosis and determination of stage of the disease. Urine samples collected from muscle-invasive high grade BCa patients (n = 24) and healthy volunteers (n = 24) were matched in terms of most common BCa risk factors i.e. gender, age, BMI and smoking status. They were analyzed by high performance liquid chromatography coupled with time of flight mass spectrometry detection (HPLC-TOF/MS) using RP and HILIC chromatography, gas chromatography hyphenated with triple quadruple mass spectrometry detection (GC-QqQ/MS) in scan mode, and proton nuclear magnetic resonance (1H NMR). The six datasets obtained were submitted to univariate and multivariate statistical analyses. 17 metabolites significantly discriminated urinary profiles of BCa patients from urinary profiles of healthy volunteers. These metabolites are mainly involved in amino acid metabolism, pyrimidine and purine metabolism, as well as energy metabolism and might play a crucial role in the pathogenesis of BCa.


Assuntos
Metabolômica , Neoplasias da Bexiga Urinária/urina , Idoso , Cromatografia Líquida de Alta Pressão , Feminino , Voluntários Saudáveis , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Espectrometria de Massas em Tandem , Neoplasias da Bexiga Urinária/metabolismo
19.
Molecules ; 24(6)2019 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-30889921

RESUMO

Origin and quality identification in dairy products is an important issue and also an extremely challenging and complex experimental procedure. The objective of the present work was to compare the metabolite profile of the lipid fraction of organic and conventional bovine milk using NMR metabolomics analysis. ¹H-NMR and 1D TOCSY NMR methods of analysis were performed on extracted lipid fraction of lyophilized milk. For this purpose, 14 organic and 16 conventional retail milk samples were collected monthly, and 64 bulk-tank (58 conventional and 6 organics) milk samples were collected over a 14-month longitudinal study in Cyprus. Data were treated with multivariate methods (PCA, PLS-DA). Minor components were identified and quantified, and modification of the currently used equations is proposed. A significantly increased % content of conjugated (9-cis, 11-trans)18:2 linoleic acid (CLA), α-linolenic acid, linoleic acid, allylic protons and total unsaturated fatty acids (UFA) and decreased % content for caproleic acid were observed in the organic samples compared to the conventional ones. The present work confirms that lipid profile is affected by contrasting management system (organic vs. conventional), and supports the potential of NMR-based metabolomics for the rapid analysis and authentication of the milk from its lipid profile.


Assuntos
Alimentos Orgânicos/análise , Lipídeos/química , Espectroscopia de Ressonância Magnética , Metabolômica/métodos , Leite/metabolismo , Animais , Bovinos , Análise Discriminante , Análise dos Mínimos Quadrados , Metaboloma , Leite/química , Valor Nutritivo , Análise de Componente Principal
20.
Talanta ; 196: 163-173, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30683346

RESUMO

Falsified medicines represent a serious threat to public health. Among the different measures to effectively combat this scourge, analytical methods play a key role in their detection and removal from the market before they reach patients. The present study evaluates for the first time the potential of a benchtop low-field (LF) Nuclear Magnetic Resonance (NMR) spectrometer for uncovering drug falsification by focusing on the analysis of fifteen erectile dysfunction and nine antimalarial medicines, the most commonly reported falsified medicines in developed and developing countries respectively. After a simple and rapid sample preparation and ≈ 5 min of spectrum recording, LF 1H NMR allows to conclude on the quality of the medicine: presence or absence of the expected active pharmaceutical ingredient (API), presence of unexpected API, absence of any API. Some 2D experiments are also described but although conclusive they are hampered by the duration of the experiments. The LF 1H NMR assay, based on the internal standard method, is validated by the determination of its accuracy, repeatability, limits of detection (LOD) and quantification (LOQ), and by comparison of the data obtained on some medicines after 45 min of spectrum recording to those measured with high-field 1H NMR. Because of its saving capabilities (cost, space, user experience), LF 1H NMR spectroscopy might become a routine screening tool in laboratories in charge of detecting falsified medicines.


Assuntos
Antimaláricos/análise , Medicamentos Falsificados/análise , Espectroscopia de Prótons por Ressonância Magnética/métodos , Agentes Urológicos/análise
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