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1.
Anal Bioanal Chem ; 415(23): 5723-5734, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37587313

RESUMO

Saffron is a unique spice obtained by drying stigmas of saffron flowers (Crocus sativus L.). Due to its high price, economically motivated adulteration occurs relatively often. The presented study aimed to develop an effective strategy for the detection of the following potential botanical adulterants used for a saffron substitution or dilution: safflower (Carthamus tinctorius L.), calendula (Calendula officinalis L.), turmeric (Curcuma longa L.), achiote (Bixa orellana L.), red pepper (Capsicum spp.), mountain arnica (Arnica montana L.), beet (Beta vulgaris L.), and pomegranate (Punica granatum L.). A non-target screening strategy based on ultra-high performance reverse-phase liquid chromatography coupled to tandem high-resolution mass spectrometry (UHPLC-HRMS/MS) was employed for the analysis of an aqueous ethanol plant extract. By using multivariate statistical methods, principal components analysis (PCA), and partial least squares discriminant analysis (PLS-DA), for processing the generated "chemical fingerprints," metabolites unique to the investigated plants could be identified. To enable routine saffron authenticity control by target screening, an internal spectral database was developed; currently, it involves 82 unique markers. In this way, the detection addition as low as 1% (w/w) of all analyzed botanical adulterants in admixture with saffron was possible. The developed method was used to control 7 saffron powder samples from the Czech market, and none of the monitored adulterants were confirmed.


Assuntos
Beta vulgaris , Produtos Biológicos , Capsicum , Crocus , Pós , Especiarias , Antioxidantes , Corantes
2.
Food Addit Contam Part B Surveill ; 16(3): 197-208, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37055876

RESUMO

The objectives of this study were to assess concentrations of three groups of persistent organic pollutants (POPs) and polycyclic aromatic hydrocarbons (PAHs) in 44 fish oil-based food supplements, to estimate their daily intake by consumers and, to evaluate the compliance of the oil samples with the oil origin declarations (cod liver oil or fish oil). The concentrations of ∑PCBs (7 congeners), OCPs (19 compounds, represented mainly by ∑DDTs), ∑PBDEs (10 congeners), and ∑PAHs (16 compounds) found in samples ranged between 0.15-55.7 µg kg-1, 0.93-72.8 µg kg-1, 0.28-27.5 µg kg-1, and 0.32-51.9 µg kg-1, respectively. Besides, the authenticity of the oils was assessed based on the fingerprints obtained by DART-HRMS, an ambient mass spectrometry technique. Four samples declared as fish oil were probably prepared from cod liver oil, which is much cheaper. Furthermore, these samples contained elevated concentrations of halogenated POPs when compared to supplements produced from fish oil.


Assuntos
Poluentes Ambientais , Bifenilos Policlorados , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Ambientais/análise , Óleos de Peixe/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Óleo de Fígado de Bacalhau/química , República Tcheca , Contaminação de Alimentos/análise , Suplementos Nutricionais/análise , Bifenilos Policlorados/análise , Monitoramento Ambiental
3.
Anal Bioanal Chem ; 414(23): 6825-6840, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35970969

RESUMO

To assess chocolate quality and authenticity comprehensively, a combination of various analytical procedures is involved, thereby making the process time-consuming and costly. Thus, we investigated the potential of ultra-high performance supercritical fluid chromatography coupled to quadrupole-time of flight mass spectrometry (UHPSFC-QTOF-MS) as an alternative to "classic" methods. By combining hexane and aqueous extracts from sequential extraction, a single 8-min analytical run enabled us (i) to determine cocoa butter equivalents (CBEs) and milk fat content based on the detection of selected triacylglycerols, (ii) to calculate dry non-fat cocoa solids based on determined theobromine and caffeine content, and (iii) to profile contained sugars. To obtain the most comprehensive information about sample composition, the MS method comprised a full MS scan for non-target screening and several time-scheduled targeted MS/MS functions ("parallel reaction monitoring") optimized according to the possible concentration ranges of the analytes. For 40 different chocolate samples, our results and those obtained by using standard methods (LC-UV for non-fat cocoa solids, and GC-FID for CBEs) were in good agreement. Compared to the conventional approach for chocolate quality and authenticity control, the presented SFC-MS method is a fast, cost-effective, and efficient alternative, and only samples suspicious for the presence of CBE should be referred to the standard GC-FID method for exact CBE quantification. In the study, also some challenges offered by SFC-MS have been addressed.


Assuntos
Cacau , Chocolate , Cromatografia com Fluido Supercrítico , Cacau/química , Cromatografia Gasosa-Espectrometria de Massas , Espectrometria de Massas em Tandem
4.
Sci Total Environ ; 833: 155137, 2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-35413344

RESUMO

Chlorinated paraffins (CPs) are an emerging group of environmental pollutants associated with adverse effects on human health (such as endocrine disruption and possible carcinogenicity). CPs are classified into several groups: short- (SCCPs), medium- (MCCPs) and long-chain chlorinated paraffins (LCCPs). In this study, CPs were determined in fish oil-based omega-3 dietary supplements (DS) representing widely consumed products that might be contaminated with various lipophilic contaminants including CPs. The CPs were isolated from DS (n = 85) by solid phase extraction. The SCCPs and MCCPs were determined by gas chromatography coupled with high-resolution mass spectrometry operated in a negative chemical ionisation mode. The LCCPs (up to C21) were screened using supercritical fluid chromatography coupled with high-resolution mass spectrometry with electrospray ionisation operated in negative mode. The CP concentrations varied from <0.01 to 56.48 µg/g fat for SCCPs (median 0.12 µg/g fat; limit of quantification, LOQ, for SCCPs was exceeded in 51 out of 85 samples) and from <0.03-89.08 µg/g fat for MCCPs (median 0.26 µg/g fat; LOQ for MCCPs was exceeded in 66 out of 85 samples), respectively. The LCCPs were not quantified in this study, nevertheless their limit of detection (0.5 µg/g fat) was exceeded in 7 out of 85 samples. Due to high levels of CPs, DS might pose as a significant source of CPs exposure to some population groups.


Assuntos
Gorduras Insaturadas na Dieta , Hidrocarbonetos Clorados , China , Gorduras Insaturadas na Dieta/análise , Suplementos Nutricionais/análise , Monitoramento Ambiental , Óleos de Peixe , Cromatografia Gasosa-Espectrometria de Massas , Hidrocarbonetos Clorados/análise , Parafina/análise
5.
Foods ; 9(9)2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32927765

RESUMO

Two alternative, complementary analytical strategies were successfully used to identify the most common meat species-beef, pork and chicken-in meat products. The first innovative high-throughput approach was based on triacylglycerols fingerprinting by direct analysis in real time coupled with high-resolution mass spectrometry (DART-HRMS). The second was the classic commonly used DNA analysis based on the use of nuclear or mitochondrial DNA in multiplex polymerase chain reaction (mPCR). The DART-HRMS method represents a rapid, high throughput screening method and was shown to have a good potential for the authentication of meat products. Nevertheless, it should be noted that due to a limited number of samples in this pilot study, we present here a proof of concept. More samples must be analyzed by DART-HRMS to build a robust classification model applicable for reliable authentication. To verify the DART-HRMS results, all samples were analyzed by PCRs. Good compliance in samples classification was documented. In routine practice under these conditions, screening based on DART-HRMS could be used for identification of suspect samples, which could be then examined and validated by accurate PCRs. In this way, saving of both labor and cost could be achieved. In the final phase, commercially available meat products from the Czech market were tested using this new strategy. Canned meats-typical Czech sausages and luncheon meats, all with declared content of beef, pork and chicken meat-were used. Compliance with the label declaration was confirmed and no adulteration was found.

6.
Plant Foods Hum Nutr ; 75(3): 376-382, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32399667

RESUMO

The composition of garlic (Allium sativum L.) may vary among cultivars and, moreover, change over time, thereby affecting both biological activity and flavour. Thus, it is important to identify the trends in the content of bioactive compounds in garlic, by reliable analytical methods. This study was focused on the key sulfur-containing compounds, S-alk(en)yl-L-cysteine sulfoxides (alliin, isoalliin, methiin, propiin), which were quantified by a fast liquid chromatography - tandem mass spectrometry (LC-MS/MS) method. Several garlic cultivars were monitored repeatedly within seven months: one month before harvest maturity; at harvest maturity; and after two and six months of storage. The results showed not only a high variability among individual cultivars, but also among samples of the same cultivar grown at different localities. During storage, a significant increase in isoalliin content (up to 54-fold after six months) occurred. Nevertheless, none of the cultivars showed significantly different properties compared to others, suggesting that many other factors affect garlic composition.


Assuntos
Alho , Cromatografia Líquida , Cisteína , Sulfóxidos , Espectrometria de Massas em Tandem
7.
Anal Bioanal Chem ; 406(16): 3909-18, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24810233

RESUMO

This study focused on the detection and quantification of organic micelle-type nanoparticles (NPs) with polysorbate components (polysorbate 20 and polysorbate 80) in their micelle shells that could be used to load biologically active compounds into fruit juice. Several advanced analytical techniques were applied in the stepwise method development strategy used. In the first phase, a system consisting of ultrahigh-performance liquid chromatography employing a size exclusion column coupled with an evaporative light scattering detector (UHPLC-SEC-ELSD) was used for the fractionation of micelle assemblies from other, lower molecular weight sample components. The limit of detection (LoD) of these polysorbate micelles in spiked apple juice was 500 µg mL(-1). After this screening step, mass spectrometric (MS) detection was utilized to confirm the presence of polysorbates in the detected micelles. Two alternative MS techniques were tested: (i) ambient high-resolution mass spectrometry employing a direct analysis in real time ion source coupled with an Orbitrap MS analyzer (DART-Orbitrap MS) enabled fast and simple detection of the polysorbates present in the samples, with a lowest calibration level (LCL) of 1000 µg mL(-1); (ii) ultrahigh-performance reversed-phase liquid chromatography coupled with high-resolution time-of-flight mass spectrometry (UHPLC-HRTOF-MS) provided highly selective and sensitive detection and quantification of polysorbates with an LCL of 0.5 µg mL(-1).


Assuntos
Bebidas/análise , Cromatografia Líquida de Alta Pressão/métodos , Aditivos Alimentares/análise , Frutas/química , Malus/química , Espectrometria de Massas/métodos , Polissorbatos/análise , Cromatografia Líquida de Alta Pressão/instrumentação , Espectrometria de Massas/instrumentação , Micelas , Nanopartículas/análise
8.
Artigo em Inglês | MEDLINE | ID: mdl-24303788

RESUMO

The dynamics of pesticide residues in strawberries that involved quantification of pesticide residues in ripe fruits after model treatment was evaluated in repeated field trials conducted over 3 years. Sixteen commercial pesticide formulations in various combinations were employed in applications from 7 to 44 days before harvest. Altogether 21 active ingredients and some of their metabolites were determined in treated strawberries using LC-MS and GC-MS methods. Except for propargite, the concentrations of all active ingredients declined below the respective MRLs (Regulation (EC) No. 396/2005); nevertheless, most of the tested fungicides often persisted above the 0.01 mg kg⁻¹ limit required by baby food producers to avoid the risk of exceeding the 'baby food limit' established in Commission Directive 2006/141/EC. On the other hand, residues of the majority of tested insecticides, namely spinosad, pymetrozine, deltamethrin, lambda-cyhalothrin and azadirachtin, declined below this limit.


Assuntos
Qualidade de Produtos para o Consumidor , Contaminação de Alimentos/prevenção & controle , Fragaria/química , Frutas/química , Fungicidas Industriais/análise , Inseticidas/análise , Resíduos de Praguicidas/análise , Adulto , Biotransformação , Fenômenos Químicos , Qualidade de Produtos para o Consumidor/legislação & jurisprudência , Cicloexanos/efeitos adversos , Cicloexanos/análise , Cicloexanos/química , Cicloexanos/metabolismo , República Tcheca , União Europeia , Contaminação de Alimentos/legislação & jurisprudência , Fragaria/crescimento & desenvolvimento , Fragaria/metabolismo , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Frutas/normas , Fungicidas Industriais/efeitos adversos , Fungicidas Industriais/química , Fungicidas Industriais/metabolismo , Fidelidade a Diretrizes , Humanos , Lactente , Alimentos Infantis/análise , Alimentos Infantis/normas , Inseticidas/efeitos adversos , Inseticidas/química , Inseticidas/metabolismo , Legislação sobre Alimentos , Resíduos de Praguicidas/efeitos adversos , Resíduos de Praguicidas/química , Resíduos de Praguicidas/metabolismo , Política Pública , Piridazinas/efeitos adversos , Piridazinas/análise , Piridazinas/química , Piridazinas/metabolismo
9.
Anal Bioanal Chem ; 402(9): 2871-83, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22287050

RESUMO

A sensitive and accurate method utilizing ultrahigh performance liquid chromatography (U-HPLC) coupled to high resolution mass spectrometry based on orbitrap technology (orbitrapMS) for the analysis of nine 3-chloropropane-1,2-diol (3-MCPD) diesters in vegetable oils was developed. To remove the interfering triacylglycerols that induce strong matrix effects, a clean-up step on silica gel column was used. The quantitative analysis was performed with the use of deuterium-labeled internal standards. The lowest calibration levels estimated for the respective analytes ranged from 2 to 5 µg kg(-1). Good recovery values (89-120%) and repeatability (RSD 5-9%) was obtained at spiking levels of 2 and 10 mg kg(-1). As an alternative, a novel ambient desorption ionization technique, direct analysis in real time (DART), hyphenated with orbitrapMS, was employed for no separation, high-throughput, semi-quantitative screening of 3-MCPD diesters in samples obtained by chromatographic fractionation. Additionally, the levels of 3-MCPD diesters measured in reallife vegetable oil samples (palm oil, sunflower oil, rapeseed oil) using both methods are reported. Relatively good agreement of the data generated by U-HPLC-orbitrapMS and DART-orbitrapMS were observed. With regard to a low ionization yield achieved for 3-MCPD monoesters, the methods presented in this paper were not yet applicable for the analysis of these contaminants at the naturally occurring levels.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Ésteres/análise , Glicerol/análogos & derivados , Espectrometria de Massas/métodos , Óleos de Plantas/análise , Glicerol/análise , alfa-Cloridrina
10.
J Agric Food Chem ; 59(11): 5919-26, 2011 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-21526761

RESUMO

A combination of direct analysis in real time (DART) ionization coupled to time-of-flight mass spectrometry (TOFMS) and chemometrics was used for animal fat (lard and beef tallow) authentication. This novel instrumentation was employed for rapid profiling of triacylglycerols (TAGs) and polar compounds present in fat samples and their mixtures. Additionally, fat isolated from pork, beef, and pork/beef admixtures was analyzed. Mass spectral records were processed by principal component analysis (PCA) and stepwise linear discriminant analysis (LDA). DART-TOFMS profiles of TAGs were found to be more suitable for the purpose of discrimination among the examined fat types as compared to profiles of polar compounds. The LDA model developed using TAG data enabled not only reliable classification of samples representing neat fats but also detection of admixed lard and tallow at adulteration levels of 5 and 10% (w/w), respectively. The presented approach was also successfully applied to minced meat prepared from pork and beef with comparable fat content. Using the DART-TOFMS TAG profiles of fat isolated from meat mixtures, detection of 10% pork added to beef and vice versa was possible.


Assuntos
Gorduras/química , Espectrometria de Massas/métodos , Animais , Bovinos , Análise Discriminante , Espectrometria de Massas/instrumentação , Carne/análise , Controle de Qualidade , Suínos , Triglicerídeos/análise
11.
Talanta ; 82(5): 1950-7, 2010 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-20875601

RESUMO

Direct analysis in real time (DART) ionization coupled to an (ultra)high resolution mass spectrometer based on orbitrap technology (orbitrapMS) was used for rapid quantitative analysis of multiple mycotoxins isolated from wheat and maize by modified QuEChERS procedure. After initial evaluation of ionization efficiencies for major groups of mycotoxins achievable with DART technology, sample preparation procedure and instrument parameter settings were optimized to obtain sensitive and accurate determination of most intensively ionizing toxins (deoxynivalenol, nivalenol, zearalenon, actyldeoxynivalenol, deepoxy-deoxynivalenol, fusarenon-X, altenuene, alternariol, alternariolmethylether, diacetoxyscirpenol, sterigmatocystin). The lowest calibration levels (LCLs) estimated for the respective analytes ranged from 50 to 150 µg kg(-1). Quantitative analysis was performed either with the use of matrix-matched standards or by employing commercially available (13)C-labeled internal standards (available for deoxynivalenol, nivalenol and zearalenon). Good recoveries (100-108%) and repeatabilities (RSD 5.4-6.9%) were obtained at spiking level 500 µg kg(-1) with isotope dilution technique. Based on matrix-matched calibration, recoveries and repeatabilities were in the range 84-118% and 7.9-12.0% (RSD), respectively. The trueness of data obtained for deoxynivalenol and zearalenon in wheat/maize by DART-orbitrapMS was demonstrated by analysis of certified reference materials (CRMs). Good agreement of these results with data generated by validated ultra-high pressure liquid chromatography-time-of-flight mass spectrometry method was documented.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Contaminação de Alimentos/análise , Micotoxinas/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Triticum/química , Zea mays/química , Limite de Detecção , Reprodutibilidade dos Testes
12.
Anal Chim Acta ; 645(1-2): 56-63, 2009 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-19481631

RESUMO

A novel approach for the authentication of olive oil samples representing different quality grades has been developed. A new type of ion source, direct analysis in real time (DART), coupled to a high-resolution time-of-flight mass spectrometer (TOFMS) was employed for the comprehensive profiling of triacylglycerols (TAGs) and/or polar compounds extracted with a methanol-water mixture. The main parameters influencing the ionization efficiency of TAGs were the type of sample solvent, degree of sample dilution, ion beam temperature, and presence of a dopant (ammonia vapors). The ionization yield of polar compounds depended mainly on a content of water in the extract and ion beam temperature. Using DART-TOFMS, not only differentiation among extra virgin olive oil (EVOO), olive pomace oil (OPO) and olive oil (OO) could be easily achieved, but also EVOO adulteration with commonly used adulterant, hazelnut oil (HO), was feasible. Based on the linear discriminant analysis (LDA), the introduced method allowed detection of HO addition of 6 and 15% (v/v) when assessing DART-TOFMS mass profiles of polar compounds and TAGs, respectively.


Assuntos
Espectrometria de Massas/métodos , Óleos de Plantas/análise , Análise Discriminante , Modelos Lineares , Metanol/química , Azeite de Oliva , Sensibilidade e Especificidade , Fatores de Tempo , Água/química
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