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1.
Mycotoxin Res ; 40(3): 447-456, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38753281

RESUMO

Poultry farming has developed into one of Algeria's most productive industrial farming because of the growing demand for sources of protein among Algerian society. Laying hen feed consists mainly of cereals, which can be contaminated with molds and subsequently with their secondary metabolites known as mycotoxins. These later can pose a serious danger to the production and quality of eggs in the commercial layer industry. This work focuses on the detection of emerging mycotoxins, mainly enniatins (ENNs) and beauvericin (BEA), in poultry feed and eggs from different locations in Algeria. Two different QuEChERS-based extractions were established to extract ENNs and BEA from chicken feed and eggs. The determination of mycotoxin occurrence was achieved by a UHPLC-MS/MS method using 0.1% (v/v) formic acid in water and MeOH as mobile phase, an ESI interface operating in positive mode, and a triple quadrupole mass spectrometer operating in MRM for the detection. Matrix-matched calibration curves were carried out for both matrices, obtaining good linearity (R2 > 0.99). The method performance was assessed in terms of extraction recovery (from 87 to 107%), matrix effect (from - 47 to - 86%), precision (RSD < 15%), and limits of quantitation (≤ 1.1 µg/kg for feed and ≤ 0.8 µg/kg for eggs). The analysis of 10 chicken feed samples and 35 egg samples composed of a 10-egg pool each showed that ENN B1 was the most common mycotoxin (i.e., found in 9 feed samples) with contamination levels ranging from 3.6 to 41.5 µg/kg, while BEA was detected only in one feed sample (12 µg/kg). However, eggs were not found to be contaminated with any mycotoxin at the detection limit levels. Our findings indicate that the searched mycotoxins are present in traces in feed and absent in eggs. This can be explained by the application of a mycotoxin binder. However, this does not put a stop on the conduction of additional research and ultimately setting regulations to prevent the occurrence of emerging mycotoxins.


Assuntos
Ração Animal , Galinhas , Ovos , Contaminação de Alimentos , Micotoxinas , Espectrometria de Massas em Tandem , Animais , Ração Animal/análise , Argélia , Micotoxinas/análise , Espectrometria de Massas em Tandem/métodos , Ovos/análise , Cromatografia Líquida de Alta Pressão/métodos , Contaminação de Alimentos/análise , Depsipeptídeos/análise
2.
Food Chem Toxicol ; 188: 114650, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38599273

RESUMO

Pesticides and mycotoxins, prominent chemical hazards in the food chain, are commonly found in plant-based foods, contributing to their pervasive presence in the human body, as evidenced by biomonitoring programs. Despite this, there is limited knowledge about their co-occurrence patterns. While intervention studies have demonstrated that organic diets can significantly reduce pesticide levels, their impact on mycotoxin exposure has been overlooked. To address this gap, this study pursued two objectives: first, to characterize the simultaneous presence of mycotoxins and pesticides in human urine samples by means of the control of the biomarkers of exposure, and second, to investigate the influence of consuming organic foods on these co-exposure patterns. A pilot study involving 20 healthy volunteers was conducted, with participants consuming either exclusively organic or conventional foods during a 24-h diet intervention in autumn 2021 and spring 2022 to account for seasonal variability. Participants provided detailed 24-h dietary records, and their first-morning urine samples were collected, minimally treated and analysed using LC-Q-ToF-MS by means of a multitargeted method in order to detect the presence of these residues. Results indicated that among the 52 screened compounds, four mycotoxins and seven pesticides were detected in over 25% of the samples. Deoxynivalenol (DON) and the non-specific pesticide metabolite diethylphosphate (DEP) exhibited the highest frequency rates (100%) and concentration levels. Correlations were observed between urine levels of mycotoxins (DON, ochratoxin alpha [OTα], and enniatin B [ENNB]) and organophosphate pesticide metabolites DEP and 2-diethylamino-6-methyl-4-pyrimidinol (DEAMPY). The pilot intervention study suggested a reduction in ENNB and OTα levels and an increase in ß-zearalenol levels in urine after a short-term replacement with organic food. However, caution is advised due to the study's small sample size and short duration, emphasizing the need for further research to enhance understanding of the human chemical exposome and refine chemical risk assessment.


Assuntos
Micotoxinas , Praguicidas , Humanos , Micotoxinas/urina , Praguicidas/urina , Masculino , Adulto , Espanha , Feminino , Projetos Piloto , Alimentos Orgânicos , Contaminação de Alimentos/análise , Dieta , Monitoramento Biológico/métodos , Adulto Jovem , Pessoa de Meia-Idade
3.
Anal Bioanal Chem ; 416(8): 1935-1949, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38321180

RESUMO

Humans are exposed to an increasing number of contaminants, with diet being one of the most important exposure routes. In this framework, human biomonitoring is considered the gold standard for evaluating human exposure to chemicals. Pesticides and mycotoxins are chemicals of special concern due to their health implications. They constitute the predominant border rejection notifications for food and feed in Europe and the USA. However, current biomonitoring studies are focused on a limited number of compounds and do not evaluate mycotoxins and pesticides together. In this study, an analytical method has been developed for the determination of 30 pesticides and 23 mycotoxins of concern in urine samples. A salting-out liquid-liquid extraction (SALLE) procedure was optimized achieving recoveries between 70 and 120% for almost all the compounds and limits as lower as when QuEChERS was applied. The compounds were then determined by liquid chromatography coupled to triple quadrupole mass spectrometry. Different chromatographic conditions and analytical columns were tested, selecting a Hypersild gold aQ column as the best option. Finally, the method was applied to the analysis of 45 urine samples, in which organophosphate and pyrethroid pesticides (detection rates (DR) of 82% and 42%, respectively) and ochratoxin A and deoxynivalenol (DR of 51% and 33%, respectively) were the most detected compounds. The proposed analytical method involves the simultaneous determination of a diverse set of pesticides and mycotoxins, including their most relevant metabolites, in human urine. It serves as an essential tool for biomonitoring the presence of highly prevalent contaminants in modern society.


Assuntos
Micotoxinas , Praguicidas , Piretrinas , Humanos , Micotoxinas/análise , Praguicidas/análise , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida/métodos , Piretrinas/análise , Cromatografia Líquida de Alta Pressão/métodos
4.
Toxins (Basel) ; 15(11)2023 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-37999496

RESUMO

Food and feed contamination with mycotoxins is a major public health concern. Humans and animals are exposed to these toxins by consuming contaminated products throughout their lives. In this study, a method based on dispersive liquid-liquid microextraction (DLLME), followed by liquid chromatography with fluorescence detection (LC-FLD), was validated for the determination of aflatoxins (AFs) M1, B1, B2, G1, G2, zearalenone (ZEN), and ochratoxin A (OTA). The method was applied to 150 raw cow milk samples and 90 market durum wheat samples from two Tunisian climatic regions: the littoral region (Mahdia) and the continental region (Béja). This work was carried out to obtain more surveillance data to support rapid initiatives to assure safe foods and protect consumer health and to estimate the daily exposure of the Tunisian population consuming those products. AFG2 and OTA were found in wheat with incidences of 54.4 and 11.1%, respectively. On the other side, milk samples were contaminated by AFG2, AFB1, and AFB2 with incidences of 8.7%, 2.0%, and 0.67%, respectively. Some of the samples showed OTA concentrations above the maximum limit allowed by the European Union, which represents a health risk for consumers in Tunisia, where no legislation exists about the maximum content of mycotoxins in food.


Assuntos
Aflatoxinas , Microextração em Fase Líquida , Micotoxinas , Humanos , Feminino , Animais , Bovinos , Micotoxinas/análise , Triticum , Leite/química , Tunísia , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida , Aflatoxina B1/análise , Contaminação de Alimentos/análise , Aflatoxinas/análise
5.
Talanta ; 253: 123946, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36167011

RESUMO

Enniatins (ENN) and beauvericin (BEA) are emerging mycotoxins that have been traditionally determined by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). However, to the best of our knowledge, no analytical methods based on capillary electrophoresis (CE)-MS/MS have been reported so far. Due to their non-polar nature, in this work, a non-aqueous CE (NACE) method coupled to quadrupole time-of-flight-MS is proposed for the first time to identify and quantify these mycotoxins. Determination was achieved in 4 min under optimum conditions: 40 mM ammonium acetate in 80:20 (v/v) acetonitrile-methanol (buffer), 30 kV (voltage), 80 cm (capillary length), 20 °C (capillary temperature) and 50 mbar × 30 s (injection). Higher selectivity can be achieved when compared with LC due to the formation of exclusive CE adducts such as [M + CH3CH2NH3]+. "All Ions" acquisition mode was selected as it allows the quantification of the usual ENNs, as well as the identity confirmation of less common ENNs. The method was validated for wheat samples, obtaining limits of quantification from 4.0 to 8.3 µg/kg depending on the emerging mycotoxin, recovery values higher than 87.4%, and intra- and inter-day precision values (RSDs) lower than 15.1% in all cases. Finally, 29 wheat samples were analyzed, finding 26 samples with concentrations of enniatin B higher than the limit of quantification (7.5-1480 µg/kg), 20 for enniatin B1 (5.2-550 µg/kg), 7 for enniatin A (10-55 µg/kg), 4 for enniatin A1 (12.6-77 µg/kg) and 5 for BEA (9.2-16.4 µg/kg). Moreover, two other ENNs were tentatively identified.


Assuntos
Micotoxinas , Cromatografia Líquida , Espectrometria de Massas em Tandem , Eletroforese Capilar
6.
J Chromatogr A ; 1682: 463502, 2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36174373

RESUMO

This work evaluates the potential of ion mobility spectrometry (IMS) to improve the analytical performance of current liquid chromatography-mass spectrometry (LC-MS) workflows applied to the determination of ergot alkaloids (EAs) in cereal samples. Collision cross section (CCS) values for EA epimers are reported for the first time to contribute to their unambiguous identification. Additionally, CCS values have been inter-laboratory cross-validated and compared with CCS values predicted by machine-learning models. Slight differences were observed in terms of CCS values for ergotamine, ergosine and ergocristine and their corresponding epimers (from 3.3 to 4%), being sufficient to achieve a satisfactory peak-to-peak resolution for their unequivocal identification. A LC-travelling wave ion mobility (TWIM)-MS method has been developed for the analysis of EAs in barley and wheat samples. Signal-to-noise ratio (S/N) was improved between 2.5 and 4-fold compared to the analog LC-TOF-MS method. The quality of the extracted ion chromatograms was also improved by using IMS.


Assuntos
Alcaloides de Claviceps , Grão Comestível/química , Alcaloides de Claviceps/análise , Ergotaminas/análise , Espectrometria de Mobilidade Iônica/métodos , Espectrometria de Massas/métodos
7.
Molecules ; 26(12)2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34207051

RESUMO

An ultra-high performance liquid chromatography coupled to tandem mass spectrometry method is proposed for the determination of the major ergot alkaloids (ergometrine, ergosine, ergotamine, ergocornine, ergokryptine, ergocristine) and their epimers (ergometrinine, ergosinine, ergotaminine, ergocorninine, ergokryptinine, and ergocristinine) in oat-based foods and food supplements. A modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) procedure was applied as sample treatment, reducing the consumption of organic solvent and increasing sensitivity. This method involved an extraction with acetonitrile and ammonium carbonate (85:15, v/v) and a clean-up step based on dispersive solid-phase extraction, employing a mixture of C18/Z-Sep+ as sorbents. Procedural calibration curves were established and limits of quantification were below 3.2 µg/kg for the studied compounds. Repeatability and intermediate precision (expressed as RSD%) were lower than 6.3% and 15%, respectively, with recoveries ranging between 89.7% and 109%. The method was applied to oat-based products (bran, flakes, flour, grass, hydroalcoholic extracts, juices, and tablets), finding a positive sample of oat bran contaminated with ergometrine, ergosine, ergometrinine, and ergosinine (total content of 10.7 µg/kg).


Assuntos
Avena/química , Alcaloides de Claviceps/química , Alimento Funcional/análise , Carbonatos/química , Cromatografia Líquida de Alta Pressão/métodos , Ergolinas/química , Ergonovina/química , Ergotaminas/química , Contaminação de Alimentos/análise , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos
8.
Toxins (Basel) ; 13(5)2021 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-33925104

RESUMO

The natural occurrence of six major ergot alkaloids, ergometrine, ergosine, ergotamine, ergocornine, ergokryptine and ergocristine, as well as their corresponding epimers, were investigated in 60 cereal samples (barley and wheat) from Algeria. Ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) and a QuEChERS extraction method were used for sample analysis. The results revealed that 12 out of 60 samples (20%) were contaminated with ergot alkaloids. Wheat was the most contaminated matrix, with an incidence of 26.7% (8 out of 30 samples). The concentration of total ergot alkaloids ranged from 17.8 to 53.9 µg/kg for barley and from 3.66 to 76.0 µg/kg for wheat samples. Ergosine, ergokryptine and ergocristine showed the highest incidences in wheat, while ergometrine was the most common ergot in barley.


Assuntos
Alcaloides de Claviceps/análise , Hordeum/química , Triticum/química , Argélia , Cromatografia Líquida de Alta Pressão , Ergolinas/análise , Ergonovina/análise , Ergotamina/análise , Ergotaminas/análise , Microbiologia de Alimentos , Limite de Detecção , Espectrometria de Massas em Tandem
9.
J Sci Food Agric ; 101(12): 5214-5224, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33609041

RESUMO

BACKGROUND: Ergot alkaloids are secondary metabolites produced by fungi in the genus Claviceps. They contaminate a large variety of cereals, such as rye, triticale, wheat and barley. The ingestion of contaminated cereals might cause adverse health effects in humans and animals. In fact, pigs, cattle, sheep, and poultry are involved in sporadic outbreaks and, although there are several studies about occurrence of ergot alkaloids in grain cereals, there are scarce studies focused on compound feed. RESULTS: Twelve ergot alkaloids have been quantified in 228 feed samples intended for swine. The analytes were extracted using QuEChERS with Z-Sep+ as sorbent in the clean-up step, which reduced the matrix effect, allowing limits of quantification between 2.1 and 21.7 µg kg-1 . The analytes were subsequently quantified by ultra-high-performance liquid chromatography with tandem mass spectrometry (UHPLC-MS/MS). A total of 29 samples (12.7%) revealed contamination by at least one ergot alkaloid, and among contaminated samples, 65% were contaminated by more than one. Only 6 of 12 target ergot alkaloids showed concentrations above the limit of quantification. The concentrations for individual ergot alkaloids ranged between 5.9 µg kg-1 for ergosinine to 145.3 µg kg-1 for ergometrine (the predominant ergot alkaloid), while the total ergot alkaloid content ranged from 5.9 to 158.7 µg kg-1 . CONCLUSIONS: The occurrence of ergot alkaloids in feed samples in Spain seems to be lower than in other regions of Europe. All the samples fulfilled current recommendations of the feed industry about practical limits for ergot alkaloids in pig feeds. This suggests that the feeds are safe for pig consumption, regarding the presence of ergot alkaloids. © 2021 Society of Chemical Industry.


Assuntos
Ração Animal/análise , Alcaloides de Claviceps/análise , Animais , Cromatografia Líquida de Alta Pressão , Grão Comestível/química , Grão Comestível/metabolismo , Grão Comestível/microbiologia , Alcaloides de Claviceps/metabolismo , Europa (Continente) , Contaminação de Alimentos/análise , Fungos/metabolismo , Hordeum/química , Hordeum/metabolismo , Hordeum/microbiologia , Suínos/metabolismo , Espectrometria de Massas em Tandem , Triticum/química , Triticum/metabolismo , Triticum/microbiologia
10.
Toxins (Basel) ; 13(1)2021 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-33451044

RESUMO

The Spanish National Network on Mycotoxins and Toxigenic Fungi and their Decontamination Processes (MICOFOOD) held its V Workshop on 10-11 December 2020. The venue was the University of Valencia, although, due to the pandemic situation, most of the participants followed the event online. Over 100 scientists, researchers, and representatives of the industry followed the Workshop, with the aim of discussing the different aspects of mycotoxin research and their impact on human and animal health, including: Study of mycotoxin-producing fungi, toxicology, analytical methods for the determination of mycotoxins, occurrence studies, reduction, and prevention, among others[...].


Assuntos
Descontaminação/métodos , Contaminação de Alimentos , Fungos , Lactobacillales/fisiologia , Micotoxinas , Animais , Biodegradação Ambiental , Regulação Fúngica da Expressão Gênica , Humanos , Mutagênicos
11.
Toxins (Basel) ; 12(4)2020 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-32340175

RESUMO

Mycotoxins are secondary metabolites produced by fungi of different species (mainly Aspergillus, Fusarium, and Penicillium) with toxic effects for humans and animals that can contaminate food and feed [...].


Assuntos
Micotoxinas/análise , Animais , Cromatografia Líquida , Monitoramento Ambiental , Contaminação de Alimentos/análise , Humanos , Espectrometria de Massas em Tandem
12.
Toxins (Basel) ; 12(3)2020 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-32204439

RESUMO

A survey on 120 cereal samples (barley, maize, rice and wheat) from Algerian markets has been carried out to evaluate the presence of 15 mycotoxins (ochratoxin A, deoxynivalenol, fumonisin B1 and B2, T-2 and HT-2 toxins, zearalenone, fusarenon X, citrinin, sterigmatocystin, enniatins A, A1, B and B1, and beauvericin). With this purpose, a QuEChERS-based extraction and ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) were used. Analytical results showed that 78 cereal samples (65%) were contaminated with at least one toxin, while 50% were contaminated with three to nine mycotoxins. T-2 toxin, citrinin, beauvericin and deoxynivalenol were the most commonly found mycotoxins (frequency of 50%, 41.6%, 40.8% and 33.3%, respectively). Fumonisins (B1 + B2), enniatins B and B1, deoxynivalenol and zearalenone registered high concentrations (289-48878 µg/kg, 1.2-5288 µg/kg, 15-4569 µg/kg, 48-2055 µg/kg and 10.4-579 µg/kg, respectively). Furthermore, concentrations higher than those allowed by the European Union (EU) were observed in 21, 8 and 1 samples for fumonisins, zearalenone and deoxinivalenol, respectively. As a conclusion, the high levels of fumonisins (B1 + B2) in maize and deoxynivalenol, zearalenone and HT-2 + T-2 toxins in wheat, represent a health risk for the average adult consumer in Algeria. These results pointed out the necessity of a consistent control and the definition of maximum allowed levels for mycotoxins in Algerian foodstuffs.


Assuntos
Exposição Dietética/análise , Grão Comestível/química , Contaminação de Alimentos/análise , Fumonisinas/análise , Tricotecenos/análise , Zearalenona/análise , Argélia , Cromatografia Líquida de Alta Pressão , Grão Comestível/normas , Humanos , Limite de Detecção , Concentração Máxima Permitida , Reprodutibilidade dos Testes , Medição de Risco , Espectrometria de Massas em Tandem , Triticum/química , Zea mays/química
13.
Food Addit Contam Part B Surveill ; 12(4): 296-302, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31791225

RESUMO

Mycotoxins have become one of the most common contaminants reported worldwide. Current legislation has established maximum levels only for some well-known mycotoxins; however, there are many other "emerging mycotoxins" for which there is no regulation, as enniatins and beauvericin. An analytical method based on salting-out assisted liquid-liquid extraction followed by ultra-high performance liquid chromatography tandem mass spectrometry is proposed for determination of enniatin A, A1, B, B1, and beauvericin in different plant-based milks, as a possible source of these contaminants, is proposed. The method showed good precision and trueness (RSD <8% and recoveries between 84-97%) with a moderate matrix effect. From a total of 32 samples of plant-based milks of different compositions (including 8 rice milks, 8 oat milks and 16 soy milks), 3 samples were contaminated with the five mycotoxins, while 5 samples were contaminated with four of them, being oat milk the most susceptible for contamination.


Assuntos
Bebidas/análise , Depsipeptídeos/análise , Contaminação de Alimentos , Micotoxinas/química , Cromatografia Líquida/métodos , Depsipeptídeos/química , Extração Líquido-Líquido , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem
14.
Toxins (Basel) ; 11(6)2019 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-31208034

RESUMO

A survey including 228 pig feed samples from Spain has been developed, exploring the occurrence of 19 mycotoxins (aflatoxins B1, B2, G1 and G2, ochratoxin A, fumonisins B1 and B2, citrinin, zearalenone, deoxynivalenol, fusarenon X, sterigmatocystin, T-2 toxin, HT-2 toxin, enniatins A, A1, B and B2, and beauvericin). The samples were analysed by solid-liquid extraction followed by liquid chromatography coupled with fluorescence or mass spectrometry detection. Enniatin B was found in 100% of the samples (up to 1200 µg/kg) and beauvericin in more than 90%. Moreover, 40% of samples were contaminated with more than five mycotoxins. This high occurrence is insurmountable and surpasses all previous studies, probably due to the inclusion of emerging mycotoxins, scarcely explored. The majority of the samples (96.9%) were in accordance with EU regulations, which do not address emerging mycotoxins or co-occurrence. These results show that in order to ensure mycotoxin absence, emerging mycotoxins should always be considered.


Assuntos
Ração Animal/análise , Contaminação de Alimentos/análise , Micotoxinas/análise , Animais , Monitoramento Ambiental , Espanha , Suínos
15.
Food Addit Contam Part B Surveill ; 11(2): 119-125, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29502487

RESUMO

The presence of Aspergillus section Flavi and aflatoxin (AF) contamination was investigated in 112 samples of peanuts, almonds and dried figs collected in Algeria. The occurrence of aflatoxin B1 (AFB1), B2 (AFB2), G1 (AFG1) and G2 (AFG2) in different commodities has been determined with a sensitive method based on high performance liquid chromatography (HPLC) coupled with fluorescence detection with post-column photochemical derivatisation. Analytical results indicated that 28 samples of peanuts, 16 samples of almonds and 26 samples of dried figs contained detectable levels of AFs. A total of 69 samples (61.6%) were contaminated with AFB1 ranging from the limit of quantification to 174 µg kg-1. AFB2 was found in 12 samples (10.7%) and varied from 0.18 to 193 µg kg-1. Seven samples revealed AF concentrations lower than the limit of quantification. Eleven peanut and fourteen dried fig samples exceeded the European maximum limits for AFB1.


Assuntos
Aflatoxinas/análise , Aspergillus flavus/isolamento & purificação , Ficus/microbiologia , Contaminação de Alimentos , Alimentos em Conserva/microbiologia , Frutas/microbiologia , Nozes/microbiologia , Aflatoxina B1/análise , Argélia , Métodos Analíticos de Preparação de Amostras , Arachis/química , Arachis/crescimento & desenvolvimento , Arachis/microbiologia , Aspergillus flavus/crescimento & desenvolvimento , Calibragem , Cromatografia Líquida de Alta Pressão , Ficus/química , Ficus/crescimento & desenvolvimento , Inspeção de Alimentos/métodos , Alimentos em Conserva/análise , Frutas/química , Frutas/crescimento & desenvolvimento , Limite de Detecção , Nozes/química , Nozes/crescimento & desenvolvimento , Processos Fotoquímicos , Prunus dulcis/química , Prunus dulcis/crescimento & desenvolvimento , Prunus dulcis/microbiologia , Reprodutibilidade dos Testes , Espectrometria de Fluorescência
16.
Anal Bioanal Chem ; 410(22): 5567-5581, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29574560

RESUMO

A fundamental step in addressing the global problem of mycotoxins is the development of highly sensitive, multi-class extraction and detection methods. This constitutes a field of research that has in recent years enjoyed a steady advance. Such methods, generally based on liquid chromatography coupled to mass spectrometry, are widely reported successfully detecting various mycotoxins in different food and feed samples. In this work, an innovative approach to multi-class mycotoxin control is proposed, offering specific advantages: a broader inclusion of more mycotoxin classes, robust and thorough extraction for all target compounds despite their varied chemical properties, and determination of all analytes from a single injection. The method involved the extraction and quantification of the main mycotoxins produced by Aspergillus, Fusarium, and Penicillium fungi, as well as their reported derivatives, together with 12 other compounds most commonly produced by Claviceps purpurea. The popularly reported QuEChERS technique has been reduced to a simple "salting-out liquid-liquid extraction" (SO-LLE) to obtain the most efficient extraction of the aforementioned mycotoxin classes in a very short time. This is in particular extremely important in ensuring correct determination of individual ergot alkaloids, for which short and robust sample preparation as well as short analytical sequences were key for minimizing the epimerization during analysis. The analyses of wheat and maize samples were performed using ultra-high performance liquid chromatography coupled with tandem mass spectrometry. Matrix-matched calibration curves were established and limits of quantification were below the maximum levels established by the EU regulation. The precision (repeatability and intermediate precision) was lower than 13% in all cases and recoveries ranged between 60 and 98% in maize and between 62 and 103% in wheat, fulfilling the current legislation. The method was applied to study the co-occurrence of these mycotoxins in wheat (n = 13) and maize (n = 15) samples from six European countries. A successful quantification of 23 different mycotoxins, from all major classes, in 85% of wheat and 93% of maize samples was achieved.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Grão Comestível/química , Alcaloides de Claviceps/análise , Contaminação de Alimentos/análise , Micotoxinas/análise , Triticum/química , Zea mays/química , Calibragem , Grão Comestível/microbiologia , Europa (Continente) , Fungos/química , Análise de Perigos e Pontos Críticos de Controle/métodos , Limite de Detecção , Extração Líquido-Líquido/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Triticum/microbiologia , Zea mays/microbiologia
17.
Food Chem ; 245: 189-195, 2018 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-29287360

RESUMO

A fast and simple analytical method was developed and characterized for the determination of aflatoxins (B1, B2, G1 and G2) in rice. The procedure is based on a simple solid-liquid extraction without further clean-up, and analysis by ultra-high performance liquid chromatography coupled with fluorescence detection. Fluorescence emission of aflatoxins B1 and G1 was enhanced by post-column chemical derivatization using pyridinium bromide perbromide. The analytical method was satisfactorily characterized in white and brown rice. Under optimum conditions, external calibration in solvent could be used for quantification purposes and limits of quantification were below the maximum contents established by the European Union regulation for these contaminants/commodity group combination (0.07-0.14 µg/kg for white rice and 0.20-0.28 µg/kg for brown rice). Recovery studies carried out at three different concentration levels (0.5, 2 and 5 µg/kg) showed values in the range of 84.5-105.3%, and RSDs ≤ 5%.


Assuntos
Aflatoxinas/análise , Cromatografia Líquida de Alta Pressão/métodos , Contaminação de Alimentos/análise , Oryza/química , Aflatoxinas/química , Fluorescência , Análise de Alimentos/métodos , Limite de Detecção
18.
Electrophoresis ; 39(4): 608-615, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29119596

RESUMO

A sensitive method using CZE-UV detection has been developed for the determination of five tetracycline antibiotics in human urine samples. To improve the sensitivity of the method, an on-line preconcentration strategy, named field-amplified sample injection, has been developed, based on the electrokinetic injection of the sample, which requires only a 1:100 dilution with sample solvent before injection. Under optimum conditions, sensitivity enhancement factors ranged from 450 to 800 for the studied compounds. The applicability of the proposed method was demonstrated by the determination of these antibiotics in spiked urine samples. The limits of quantification were lower than 0.8 mg/L and the precision (intra- and inter-day), expressed as %RSD was below 14%. Recoveries ranged from 92.1 to 96.7%. Thus, the proposed procedure is a simple, fast and efficient strategy which could be used as therapeutic drug monitoring in human urine samples.


Assuntos
Eletroforese Capilar/métodos , Tetraciclinas/urina , Humanos , Limite de Detecção , Modelos Lineares , Masculino , Reprodutibilidade dos Testes
19.
J Chromatogr A ; 1524: 283-289, 2017 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-28992989

RESUMO

The on-line coupling of micellar electrokinetic chromatography and mass spectrometry (MEKC-MS) is often hampered by incompatibility problems leading to reduced separation performance and unfavorable limits of detection (LODs). Here we propose a new selective and highly sensitive MEKC-MS/MS method employing a sheathless porous-tip interface in combination with a micellar phase comprised of semi-volatile surfactant molecules. Carbamate pesticides (CRBs) were selected as representative model compounds being neutral toxic pollutants potentially present at trace levels in environmental water samples. A background electrolyte of 75mM perfluorooctanoic acid adjusted to pH 9.0 with ammonium hydroxide allowed efficient separation of 15 CRBs and appeared fully compatible with electrospray ionization (ESI)-MS. Interfacing parameters, such as the distance between the capillary tip and mass-spectrometer inlet, ESI voltage, and dry gas temperature and flow were optimized in order to attain good spray stability and high analyte signal-to-noise ratios. For CRBs the LODs ranged from 0.2 to 3.9ngL-1 (13nL injected, i.e., 2% of capillary volume), representing an improvement for certain CRBs of more than 300-fold when compared with conventional sheath-liquid interfacing. Good linearity (R2>0.99) and satisfactory reproducibility were obtained for all CRBs with interday RSD values for peak area and migration time of 4.0-11.3% and below 1.5%, respectively. Analysis of spiked mineral water showed that the new MEKC-MS/MS method allows selective and quantitative determination of CRB concentrations below the maximum residue limit of 100ngL-1 without the need for sample preconcentration.


Assuntos
Técnicas de Química Analítica/métodos , Cromatografia Capilar Eletrocinética Micelar , Monitoramento Ambiental/métodos , Espectrometria de Massas em Tandem , Poluentes Químicos da Água/análise , Caprilatos/química , Carbamatos/análise , Técnicas de Química Analítica/instrumentação , Monitoramento Ambiental/instrumentação , Fluorocarbonos/química , Limite de Detecção , Espectrometria de Massas/métodos , Reprodutibilidade dos Testes , Razão Sinal-Ruído , Tensoativos/química
20.
Artigo em Inglês | MEDLINE | ID: mdl-28820044

RESUMO

Vegetable milks are considered as functional foods due to their physiological benefits. Although the consumption of these products has significantly increased, they have received little attention in legislation with regard to contaminants. However, they may contain mycotoxins resulting from the use of contaminated raw materials. In this work, ultra-high-performance liquid chromatography tandem mass spectrometry has been proposed for the determination of the most relevant Fusarium toxins (fumonisin B1 and B2, HT-2 and T-2 toxins, zearalenone, deoxynivalenol and fusarenon-X) in different functional beverages based on cereals, legumes and seeds. Sample treatment consisted of a simple salting-out-assisted liquid-liquid extraction with no further clean-up. The method provided limits of quantification between 3.2 and 57.7 µg L-1, recoveries above 80% and precision with RSD lower than 12%. The method was also applied for studying the occurrence of these mycotoxins in market samples of vegetable functional beverages and deoxynivalenol was found in three oat-based commercial drinks.


Assuntos
Contaminação de Alimentos/análise , Fusarium/química , Extração Líquido-Líquido , Leite/química , Micotoxinas/análise , Espectrometria de Massas em Tandem , Verduras/química , Animais , Cromatografia Líquida de Alta Pressão , Sais
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