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1.
Food Chem ; 300: 125176, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31351258

RESUMO

Mycotoxins are toxic metabolites produced by fungi or molds, which may cause serious harm to human health through polluted cereal foods. In order to measure the typical mycotoxin contaminations in wheat and corn, a surface plasmon resonance (SPR) method was established using SPR sensor chip that was fabricated based on self-assembled monolayer. The minimum detection limit of aflatoxin B1, ochratoxin A, zearalenone and deoxynivalenol were identified as 0.59 ng/mL, 1.27 ng/mL, 7.07 ng/mL and 3.26 ng/mL, respectively. The cross-reactivity for all four mycotoxins were demonstrated to be low. Moreover, the test data were compared with HPLC-MS/MS confirmatory analysis results and good agreement was found between them. In conclusion, the SPR method for simultaneously detecting four mycotoxins has been developed with high sensitivity, good linearity and specificity, which can meet the detection requirements of cereal foods.


Assuntos
Micotoxinas/análise , Ressonância de Plasmônio de Superfície/métodos , Triticum/química , Zea mays/química , Aflatoxina B1/análise , Aflatoxina B1/imunologia , Cromatografia Líquida de Alta Pressão , Reações Cruzadas , Análise de Alimentos/instrumentação , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Hidrazonas/química , Limite de Detecção , Micotoxinas/imunologia , Ocratoxinas/análise , Ocratoxinas/imunologia , Sensibilidade e Especificidade , Ressonância de Plasmônio de Superfície/instrumentação , Espectrometria de Massas em Tandem , Tricotecenos/análise , Tricotecenos/imunologia , Triticum/microbiologia , Zea mays/microbiologia , Zearalenona/análise , Zearalenona/imunologia
2.
Food Chem ; 297: 124912, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31253263

RESUMO

An anti-idiotypic nanobody-phage display-mediated immuno-polymerase chain reaction (PD-IPCR) method was developed for simultaneous quantitative detection of total aflatoxins and zearalenone in cereals. Two phages, displaying the variable domain of the heavy chain anti-idiotypic nanobody that binds aflatoxin- or zearalenone-specific monoclonal antibody (1C11 or 2D3), were used as competitors for corresponding analytes. Specific DNA sequences encoding anti-idiotypic nanobodies were used to design the primers for PCR amplification. The results indicated that detection limits for total aflatoxins and zearalenone in a sample were 0.03 and 0.09 ng mL-1, respectively. Recoveries of spiked aflatoxins and zearalenone were 80-118% and 76.7-111%, respectively. Validation results were in good agreement with the gold-standard high-performance liquid chromatography method. This report is the first to describe PD-IPCR for simultaneous quantitative detection of total aflatoxins and zearalenone in cereals.


Assuntos
Aflatoxinas/análise , Anticorpos Anti-Idiotípicos/imunologia , Imunoensaio/métodos , Zearalenona/análise , Aflatoxinas/imunologia , Anticorpos Anti-Idiotípicos/genética , Cromatografia Líquida de Alta Pressão , Limite de Detecção , Oryza/química , Oryza/metabolismo , Biblioteca de Peptídeos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Anticorpos de Domínio Único/genética , Anticorpos de Domínio Único/imunologia , Zea mays/química , Zea mays/metabolismo , Zearalenona/imunologia
3.
Talanta ; 201: 397-405, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31122440

RESUMO

This article reports the identification, engineering and characterisation of recombinant single chain variable fragment (scFv) antibody against Zearalenone (ZEN), an oestrogenic mycotoxin, using phage display antibody technology. To increase the chance of obtaining clones that can bind to free toxin, the conjugated proteins of the target antigen, i.e. bovine serum albumin ZEN-BSA and ovalbumin ZEN-OVA, were switched during the biopanning. One phage-displayed scFv clone specific to free ZEN, designated yZEN2A8, could be isolated. The gene encoding the yZEN2A8 scFv was sub-cloned into the pET-21d (+) and pKP300 delta III vectors to generate the recombinant scFv and scFv-AP antibody formats, respectively. After ELISA optimisation by checkerboard titration, the sensitivities of the recombinant yZEN2A8 scFv antibody and scFv-AP fusion were improved approx. 2 and 60 folds, respectively. Competitive ELISA indicated that the median inhibition concentration (IC50) of recombinant yZEN2A8 scFv antibody and scFv-AP fusion after ELISA optimisation were 90 and 14 ng mL-1, with a limit of detection (LOD) of 20 and 2 ng mL-1, respectively. No cross-reactivity to other common mycotoxins was observed. Homology modelling illustrated specific binding of the recombinant antibody to ZEN and demonstrated the role of complementary determining regions (CDRs) of both the variable heavy and light chains in antibody-antigen interactions. Efficient application of scFv-AP for the detection of ZEN contamination in corns and wheat samples were investigated for the first time. The antibody in the form of scFv-AP can be used as a prototype for the development of a convenient reagent for the detection of ZEN contamination in various format, including biosensor-based.


Assuntos
Ração Animal/análise , Contaminação de Alimentos/análise , Proteínas Recombinantes de Fusão/imunologia , Anticorpos de Cadeia Única/imunologia , Zearalenona/análise , Fosfatase Alcalina/genética , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/imunologia , Técnicas de Visualização da Superfície Celular/métodos , Ensaio de Imunoadsorção Enzimática/métodos , Escherichia coli/genética , Humanos , Simulação de Acoplamento Molecular , Biblioteca de Peptídeos , Ligação Proteica , Coelhos , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Anticorpos de Cadeia Única/biossíntese , Anticorpos de Cadeia Única/genética , Anticorpos de Cadeia Única/metabolismo , Triticum/química , Zea mays/química , Zearalenona/imunologia , Zearalenona/metabolismo
4.
Food Chem ; 292: 98-105, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31054698

RESUMO

Accurate and early diagnosis of mycotoxin is particularly significant to the food and agricultural product safety. In the present work, a sensitive and effective monitoring method for zearalenone (ZEN) was exploited based on a novel self-enhanced electrochemiluminescence (ECL) aptasensor. The self-enhanced lumonophore was compounded by electrostatically combining amine-functionalized Ru(bpy)32+-doped silica nanoparticles (NH2-Ru@SiO2 NPs) and nitrogen doped graphene quantum dots (NGQDs) together. Since the emitter and co-reactant simultaneously existed in the same nanoparticle, shortened electron-transfer distance and decreased energy loss was obtained. Therefore, self-enhanced ECL aptasensor based on the novel complex expressed the widest linear range of 10 fg mL-1-10 ng mL-1 and the lowest detection limit of 1 fg mL-1 for ZEN detection. More importantly, ZEN produced during the mildew process of corn flour was monitored by the developed aptasensor, which exhibited superior determination and potential application in real samples.


Assuntos
Aptâmeros de Nucleotídeos/química , Medições Luminescentes/métodos , Nanopartículas/química , Zea mays/metabolismo , Zearalenona/análise , 2,2'-Dipiridil/análogos & derivados , 2,2'-Dipiridil/química , Farinha/análise , Grafite/química , Limite de Detecção , Compostos Organometálicos/química , Pontos Quânticos/química , Reprodutibilidade dos Testes , Dióxido de Silício/química , Zea mays/química
5.
Food Chem ; 286: 282-288, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-30827607

RESUMO

Zearalenone is a contaminant in food and feed products which are hazardous to humans and animals. This study explored the feasibility of the Raman rapid screening technique for zearalenone in contaminated maize. For representative Raman spectra acquisition, the ground maize samples were collected by extended sample area to avoid the adverse effect of heterogeneous component. Regression models were built with partial least squares (PLS) and compared with those built with other variable selection algorithms such as synergy interval PLS (siPLS), ant colony optimization PLS (ACO-PLS) and siPLS-ACO. SiPLS-ACO algorithm was superior to others in terms of predictive power performance for zearalenone analysis. The best model based on siPLS-ACO achieved coefficients of correlation (Rp) of 0.9260 and RMSEP of 87.9132 µg/kg in the prediction set, respectively. Raman spectroscopy combined multivariate calibration showed promising results for the rapid screening large numbers of zearalenone maize contaminations in bulk quantities without sample-extraction steps.


Assuntos
Algoritmos , Análise Espectral Raman/métodos , Zea mays/química , Zearalenona/análise , Calibragem , Cromatografia Líquida de Alta Pressão , Inocuidade dos Alimentos , Análise dos Mínimos Quadrados , Análise Espectral Raman/normas , Zea mays/metabolismo , Zearalenona/normas
6.
Food Chem ; 288: 22-28, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30902285

RESUMO

An analytical method based on a QuEChERS procedure (quick, easy, cheap, effective, rugged and safe) has been developed for the determination of mycotoxins (α-zearalenol and zearalenone, and aflatoxins B1, B2, G1 and G2) in edible oils. The analysis was performed by ultra-high performance liquid chromatography coupled to triple quadrupole analyser (UHPLC-QqQ-MS/MS). The method was fully validated and the quantification limit is 0.5 µg kg-1 for aflatoxins and 1 µg kg-1 for α-zearalenol and zearalenone. Suitable recoveries were obtained at low concentration levels (0.5-25 µg kg-1 for aflatoxins and 1-25 µg kg-1 for α-zearalenol and zearalenone), ranging from 80 to 120%. Intra and inter-day precision values were also evaluated and relative standard deviation was lower than 20%. The expanded uncertainty, U, was also evaluated ant it was below 32% at 25 µg kg-1. The validated method has been applied to monitor the presence of mycotoxins in 194 samples belonging to different types of edible oils (olive oil, sunflower oil, soy oil and corn oil). Zearalenone was detected in 25% of the analysed samples at concentrations up to 25.6 µg kg-1, and aflatoxin G1 and G2 in 3% and 14% of the samples at a maximum concentration of 1.9 and 6.8 µg kg-1 respectively.


Assuntos
Cromatografia Líquida de Alta Pressão , Micotoxinas/análise , Óleos Vegetais/metabolismo , Espectrometria de Massas em Tandem , Aflatoxinas/análise , Limite de Detecção , Azeite de Oliva/metabolismo , Zearalenona/análise , Zeranol/análogos & derivados , Zeranol/análise
7.
Anal Bioanal Chem ; 411(10): 2169-2175, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30820630

RESUMO

Zearalenone (ZEN) is a common carcinogenic toxin related to cereal contamination. In this study, we developed a high sensitivity quantum dot (QD)-based fluorescent quenching lateral flow assay (LFA) for sensitive ZEN detection. The linear detection range of the fluorescent quenching LFA for ZEN was 0.78-25 ng/mL, and the limit of detection was 0.58 ng/mL. In addition, the fluorescent quenching LFA showed high recovery (83.1-93.6%) for detection of ZEN concentrations spiked into corn samples. These results indicate that the QD-based fluorescent quenching LFA may be a valuable tool for preliminary screening of ZEN contamination.


Assuntos
Carcinógenos/análise , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Pontos Quânticos/química , Zea mays/química , Zearalenona/análise , Grão Comestível/química , Desenho de Equipamento , Fluorescência , Análise de Alimentos/instrumentação , Limite de Detecção , Pontos Quânticos/ultraestrutura , Espectrometria de Fluorescência/instrumentação , Espectrometria de Fluorescência/métodos
8.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1110-1111: 43-50, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30776614

RESUMO

Zearalenone is one of the most harmful mycotoxins found in grains and there is a large demand for zearalenone substrate for research purposes. A new separation method was developed for the preparative purification of zearalenone from rice culture of Fusarium graminearum by utilizing macroporous resin column combined with high-speed counter-current chromatography. Zearalenone was adsorpted on XAD-2 resin at 25 °C, neutral pH and a feed flow of 4 BV/h, followed by dynamic desorption by 60% ethanol solution. Further purification was achieved by high-speed counter-current chromatography using an optimized biphasic solvent system. A total of 267 mg of zearalenone crystal was obtained in one single run from 4.2 g of crude extract. The purity of the final product was 98.9% and the total recovery yield of zearalenone in this study was 73.9%. This dual-step purification procedure provided an effective way to obtain the costly mycotoxin for both toxicological and detoxification studies on zearalenone.


Assuntos
Distribuição Contracorrente/métodos , Oryza/microbiologia , Poliestirenos/química , Zearalenona/isolamento & purificação , Adsorção , Técnicas de Cultura de Células , Cromatografia Líquida de Alta Pressão/métodos , Etanol , Fusarium/metabolismo , Zearalenona/análise , Zearalenona/química , Zearalenona/metabolismo
9.
Biosens Bioelectron ; 129: 139-146, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30690178

RESUMO

Low molecular weight pollutants from foods have aroused global attention due to their toxicity after long-time exposure. There is an increased demand for appropriate methods to detect these pollutants in foods. In this study, a brand-new type of nano metal-organic coordination polymers (MOCPs) nanocarriers (3D sakura-shaped copper (II) ions@L-glutamic acid (L-Glu)) has been first synthesized. We herein demonstrate a facile chelated method that allows the combination of copper (II) ions and L-Glu. A series of controlled experiments have revealed that the reaction time and the ratio of reactants played the crucial roles in affecting the morphology of the final product. 3D sakura-shaped Cu@L-Glu combined with palladium-platinum nanoparticle (Pd-PtNPs) to obtain Cu@L-Glu/Pd-PtNPs acting as the signal tag, which applied in electrochemical aptasensor for ultrasensitive detection of zearalenone (ZEN). A glassy carbon electrode was first modified with spherical Au-PANI-Au nanohybrids to enhance the conductivity and immobilize more amino modified ZEN aptamer. Cu@L-Glu/Pd-PtNPs were labeled with Complementary DNA (partial matching with ZEN aptamer) to form bioconjugates for signal amplification. After the hybridization reaction of ZEN aptamer and the bioconjugates, a significant electrochemical signal from the catalysis of H2O2 by Cu@L-Glu/Pd-PtNPs can be observed. ZEN competed with bioconjugates for binding to ZEN aptamer, resulting in decreased the electrochemical signal. Chronoamperometry was applied to record the final electrochemical signals. Under optimal conditions, the electrochemical aptasensor exhibited desirable sensitive detection of ZEN with a wide linearity ranging from 1 fg/mL to 100 ng/mL and a relatively low detection limit of 0.45 fg/mL (S/N = 3). Furthermore, the proposed electrochemical aptasensor shows excellent selectivity to the ZEN in the presence of possible interfering substances, and has potential application for ZEN detection in food samples.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Cobre/química , Ácido Glutâmico/química , Nanoestruturas/química , Polímeros/química , Zearalenona/análise , Técnicas Eletroquímicas/métodos , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Ouro/química , Limite de Detecção
10.
J Sci Food Agric ; 99(1): 482-485, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-29808470

RESUMO

BACKGROUND: The aim of this study was to investigate whether the application of selenium (Se) ions directly to the leaf surface can protect plants against infection by the fungal toxin zearalenone (ZEA). The experiments were performed for the most common and agronomically important crops such as wheat, oat, and barley (both tolerant and sensitive varieties) because mycotoxin accumulation in plants is the cause of many diseases in animals and people. RESULTS: ZEA at a concentration of 10 µmol L-1 either alone or in combination with Se (5 µmol L-1 Na2 SeO4 ) was applied to the second leaf of seedlings. Visualization of leaf temperature profiles by infrared thermography demonstrated a decrease in temperature at the location of ZEA infection that was more noticeable in sensitive genotypes. The presence of Se significantly suppressed changes at the site of ZEA application in all tested plants, especially the tolerant genotypes. Microscopic observations confirmed that foliar administration of ZEA resulted in its penetration to deeper localized cells and that damage induced by ZEA (mainly to chloroplasts) decreased after Se application. Analyses of antioxidant enzymes demonstrated the involvement of Se in antioxidation mechanisms, in particular by activating SOD and CAT under ZEA-induced stress conditions. CONCLUSION: The foliar application of Se to seedling leaves may be a non-invasive method of protecting crops against the first steps of ZEA infection. © 2018 Society of Chemical Industry.


Assuntos
Avena/microbiologia , Hordeum/microbiologia , Folhas de Planta/efeitos dos fármacos , Selênio/farmacologia , Triticum/microbiologia , Zearalenona/análise , Avena/química , Avena/efeitos dos fármacos , Avena/genética , Produção Agrícola , Fungos/efeitos dos fármacos , Fungos/metabolismo , Genótipo , Hordeum/química , Hordeum/efeitos dos fármacos , Hordeum/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Folhas de Planta/química , Folhas de Planta/genética , Folhas de Planta/microbiologia , Triticum/química , Triticum/efeitos dos fármacos , Triticum/genética , Zearalenona/metabolismo
11.
Neuro Endocrinol Lett ; 39(4): 325-330, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30531702

RESUMO

INTRODUCTION: Zearalenone (ZEA) and deoxynivalenol (DON) are toxic fungal secondary metabolites, found mainly in contaminated food, that are associated with serious health problems. It is important to identify undesirable toxins and metabolites that may be present in human milk. The aim of this study was to evaluate human milk ZEA and DON levels, total daily intake of ZEA and DON; and their possible relationship with maternal dietary habits. METHODS: We enrolled 90 lactating mothers who had 7- to 90-day-old babies. A dietary questionnaire was completed by each of the mothers. Human milk samples were obtained from 90 mothers, and human milk ZEA and DON levels were evaluated with the solid-phase direct enzyme immunoassay. The total daily intake (TDI) was calculated for the 63 exclusively breastfed infants. RESULTS: ZEA was detected in all human milk samples; median was 173.8 ng/L (35.7-682 ng/L). The calculated median TDI for ZEA was 33.0 ng/kg body weight (bw) (10.4-120.5 ng/kg) among exclusively breast-fed infants, none of them had a TDI that was above the previously defined threshold levels. Human milk ZEA levels were associated with the maternal consumption of meat, fish, dry fig, dried apricot, flaked red spice and spice. The median DON levels was 3924 ng/L (400-14997 ng/L). The median TDI of DON was 750 ng/kg (240-2774 ng/kg) among exclusively breastfed infants and 36% out of them, the TDI for DON was above the previously defined threshold level. Human milk DON levels were associated with the maternal meat consumption. CONCLUSIONS: Our findings are indicative of dietary exposure to mycotoxins during the pregnancy and lactation periods in nursing mothers. Further, the excessive TDI values for DON observed in 36% of the exclusively breastfed infants point to the need for further regulations and recommendations on the dietary habits of pregnant/nursing mothers in order to avoid exposure to potential mycotoxins.


Assuntos
Exposição Dietética , Leite Humano/química , Tricotecenos/análise , Zearalenona/análise , Adolescente , Adulto , Dieta , Feminino , Humanos , Carne , Turquia , Adulto Jovem
12.
Se Pu ; 36(6): 566-572, 2018 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-30136479

RESUMO

A method was developed for the simultaneous determination of α-zearalanol, ß-zearalanol, α-zearalenol, ß-zearalenol, zearalenone and zearalanone residues in milk samples by ultra-performance convergence chromatography-tandem mass spectrometry (UPC2-MS/MS) after immunoaffinity column-solid phase extraction (IAC-SPE). The sample was diluted with deionized water and cleaned with IAC-SPE. The chromatographic separation was performed on an ACQUITY UPC2 Torus 2-PIC column (50 mm×3.0 mm, 1.7 µm) using the mobile phases of supercritical carbon dioxide and methanol containing 0.1% (v/v) formic acid with gradient elution. The separated compounds were detected in negative electrospray ionization (ESI-) mode. The results showed no significant matrix effect after cleaning by IAC-SPE. The calibration curves of the six compounds were linear in the range of 1-200 ng/mL (correlation coefficients (r2) ≥ 0.9957). The recoveries were 75.9%-106.5% in the three spiked levels, and the intra-day and inter-day precisions were no more than 11.4%. The method is specific, environment friendly, and is suitable for the rapid determination of α-zearalanol, ß-zearalanol, α-zearalenol, ß-zearalenol, zearalenone and zearalanone residues in milk samples.


Assuntos
Contaminação de Alimentos/análise , Leite/química , Zearalenona/análise , Zeranol/análise , Animais , Cromatografia Líquida de Alta Pressão , Extração em Fase Sólida , Espectrometria de Massas em Tandem , Zeranol/análogos & derivados
13.
Artigo em Inglês | MEDLINE | ID: mdl-29909149

RESUMO

Six aflatoxins (AFs; AF B1, B2, G1, G2, M1 and M2) and six zearalenone (ZEN) analogs (ZEN, zearalanone, α-zeralanol, ß-zeralanol, α-zearalenol, and ß-zearalenol) were simultaneously extracted from edible and medicinal herbs using a group-specific immunoaffinity column (IAC) and then identified by ultra-high-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). The IAC was prepared by coupling N-hydroxysuccinimide-activated Sepharose 4B Fast Flow gel with two group-specific monoclonal antibodies. The column capacities to six AFs and six ZEN analogs ranged from 100.2 ng to 167.1 ng and from 59.5 ng to 244.4 ng, respectively. The IAC-UPLC-MS/MS method was developed and validated with three different matrices (Chinese yam [Dioscorea polystachya], Platycodon grandiflorum and coix seed [Semen Coicis]). Recoveries of twelve analytes from edible and medicinal herbs were in the range of 64.7%-112.1%, with relative standard deviations below 13.7%. The limits of quantification were in the range from 0.08 µg kg-1 to 0.2 µg kg-1. The method was proven to be sensitive and accurate, and suitable for the determination of real samples.


Assuntos
Aflatoxinas/análise , Cromatografia de Afinidade/métodos , Plantas Medicinais/química , Espectrometria de Massas em Tandem/métodos , Zearalenona/análise , Cromatografia Líquida de Alta Pressão/métodos , Modelos Lineares , Extratos Vegetais/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
14.
Food Chem ; 267: 140-148, 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-29934148

RESUMO

In this report, a UPLC-ESI-MS/MS method for the simultaneous determination of aflatoxins, ochratoxin A, zearalenone, deoxynivalenol, fumonisins, T-2 and HT-2 toxins, fusarenone X, diacetoxyscirpenol, and 3- and 15-acetyldeoxynivalenol in feedstuffs was developed. A quadrupole-time-of-flight mass spectrometer detector (QTOF-MS) operating in full scan mode was combined with the UPLC-ESI-MS/MS system to confirm the identity of detected mycotoxins and to identify other possible microbial metabolites occurring in samples. Sixty-two feed samples from the Spanish market were analyzed. Extraction of metabolites was carried out with acetonitrile-water-formic acid (80:19:1, v/v/v). Method detection and quantification limits and performance criteria set by Commission Regulation (EC) No 401/2006 were fulfilled. Relatively high levels of the main regulated mycotoxins and presence of non-regulated mycotoxins in feed samples were found. This is the first study in which mycotoxins and other microbial metabolites occurring in feed are studied using a UPLC-QTOF-MS system being therefore a reference report.


Assuntos
Ração Animal/análise , Micotoxinas/análise , Aflatoxinas/análise , Cromatografia Líquida de Alta Pressão , Fumonisinas/análise , Espectrometria de Massas/métodos , Ocratoxinas , Toxina T-2/análogos & derivados , Toxina T-2/análise , Tricotecenos/análise , Zearalenona/análise
15.
Food Chem Toxicol ; 118: 830-848, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29935247

RESUMO

This study aimed to estimate the prevalence and concentration of total aflatoxin (TAF) ochratoxin A (OTA), zearalenone (ZEN) and deoxynivalenol (DON) in bread, cornflakes, breakfast cereals and pasta-based products through meta-analysis. The required databases including (PubMed and Scopus databases) were investigated to collect data on the concentration and prevalence of mentioned mycotoxins in cereal-based products. Among 2461 explored articles in identification step, 38 articles with 9627 samples were included in the conducted meta-analysis. The prevalence and concentration of studied mycotoxins varied with the cereal-based food studied. In this context, the overall rank order of mycotoxins prevalence in the cereal foods was OTA > DON > ZEN > TAF > 15-ADON > 3-ADON. Also, the overall rank order of mycotoxins based on concentration in the cereal foods investigated was DON > ZEN > 15-ADON > OTA > 3-ADON > TAF. The findings of this meta-analysis may be useful for the building of risk assessment models aiming to derive data for the development of specific actions to reduce the exposure to OTA, ZEN, TAF, and DON through the consumption of the cereal-based products.


Assuntos
Aflatoxinas/análise , Grão Comestível/química , Contaminação de Alimentos/análise , Ocratoxinas/análise , Tricotecenos/análise , Zearalenona/análise , Prevalência
16.
Artigo em Inglês | MEDLINE | ID: mdl-29889651

RESUMO

The peroxidase (POD) enzyme, obtained from different sources, has been described in the literature regarding its good results of reduction in concentration or degradation levels of mycotoxins, such as aflatoxin B1, deoxynivalenol and zearalenone (ZEA). This study aimed at evaluating the action of commercial POD and POD from soybean bran (SB) and rice bran (RB) in ZEA reduction in a model solution and the characterisation of the mechanism of enzyme action. POD was extracted from SB and RB in phosphate buffer by orbital agitation. Evaluation of the action of commercial POD and POD from SB and RB in ZEA reduction was carried out in phosphate buffer and aqueous solution, respectively. Parameters of (Michaelis-Menten constant) (KM) and maximal rate (Vmax) were determined in the concentration range from 0.16 to 6 µg mL-1. ZEA reduction was determined and the mechanism of enzyme action was characterised by FTIR and high-pressure liquid chromatography-electrospray tandem mass spectrometry. Commercial POD and POD from RB and SB reduced ZEA concentration by 69.9%, 47.4% and 30.6% in 24 h, respectively. KM values were 39.61 and 8.90 µM, whereas Vmax values were 0.170 and 0.011 µM min-1 for commercial POD and POD from RB, respectively. The characterisation of the mechanism of enzyme action showed the oxidoreductive action of commercial POD in the mycotoxin. The use of commercial POD and POD from agro-industrial by-products, such as SB and RB, could be a promising alternative for ZEA biodegradation.


Assuntos
Contaminação de Alimentos/análise , Peroxidases/metabolismo , Soja/enzimologia , Zea mays/enzimologia , Zearalenona/análise , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas em Tandem , Zearalenona/metabolismo
17.
Anal Bioanal Chem ; 410(22): 5583-5592, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29707753

RESUMO

Zearalenone (ZEN) major biotransformation pathways described so far are based on glycosylation and sulfation, although acetylation of trichothecenes has been reported as well. We investigated herein the ZEN acetylation metabolism route in micropropagated durum wheat leaf, artificially contaminated with ZEN. We report the first experimental evidence of the formation of novel ZEN acetylated forms in wheat, attached both to the aglycone backbone as well as on the glucose moiety. Thanks to the advantages provided by high-resolution mass spectrometry, identification and structure annotation of 20 metabolites was achieved. In addition, a preliminary assessment of the toxicity of the annotated metabolites was performed in silico focusing on the toxicodynamic of ZEN group toxicity. All the metabolites showed a worse fitting within the estrogen receptor pocket in comparison with ZEN. Nevertheless, possible hydrolysis to the respective parent compounds (i.e., ZEN) may raise concern from the health perspective because these are well-known xenoestrogens. These results further enrich the biotransformation profile of ZEN, providing a helpful reference for assessing the risks to animals and humans. Graphical abstract ᅟ.


Assuntos
Fusarium/metabolismo , Espectrometria de Massas em Tandem/métodos , Triticum/metabolismo , Triticum/microbiologia , Zearalenona/metabolismo , Acetilação , Biotransformação , Cromatografia Líquida de Alta Pressão/métodos , Glucosídeos/análise , Glucosídeos/metabolismo , Análise de Perigos e Pontos Críticos de Controle/métodos , Modelos Moleculares , Folhas de Planta/metabolismo , Folhas de Planta/microbiologia , Zearalenona/análise
18.
Anal Chim Acta ; 1025: 163-171, 2018 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-29801605

RESUMO

Immunochromatographic assay (ICA) is a promising technology for on-site detection. Nonetheless, the wide-scale application of ICA is hindered by several disadvantages, such as poor reproducibility, low sensitivity, and single-target detection. Thus, a novel quantum dot nanobead (QB)-based multiplexed ICA (QB-ICA) with multiple test lines was developed in this study for the simultaneous quantitative detection of aflatoxin B1 (AFB1) and zearalenone (ZEN), where QBs with high luminescence were used as labels to enhance the analytical sensitivity of the ICA. Moreover, a streptavidin (SA)-biotin system, which was undisturbed by the target mycotoxins, was introduced as the signal output for the control line. Consequently, stable and reliable T/C values (ratios of signals on the test line to that of the control line) were obtained as quantitative signals. The proposed QB-ICA demonstrated high sensitivity for the simultaneous detection of AFB1 and ZEN, of which the half-maximal inhibitory concentrations reached as low as 38.98 pg mL-1 and 1.23 ng mL-1, respectively. At 10% competitive inhibition concentration, the limit detections (LOD) were 1.65 and 59.15 pg mL-1 for AFB1 and ZEN, respectively. The average recoveries of the intra- and inter-assays ranged from 81.77% to 119.70% and from 94.18% to 111.4% for AFB1 and ZEN quantification, respectively, and the variation coefficients were less than 12%, thereby indicating that the proposed method is highly accurate and robust. These findings suggest that QB-ICA using SA-biotin system as the signal output of control line is an excellent point-of-care platform for the rapid screening of mycotoxins.


Assuntos
Aflatoxina B1/análise , Cromatografia de Afinidade/métodos , Pontos Quânticos/química , Fitas Reagentes/análise , Zearalenona/análise , Anticorpos Monoclonais/química , Biotina/química , Cromatografia de Afinidade/instrumentação , Desenho de Equipamento , Limite de Detecção , Luminescência , Substâncias Luminescentes/química , Pontos Quânticos/ultraestrutura , Reprodutibilidade dos Testes , Estreptavidina/química
19.
Talanta ; 186: 97-103, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-29784425

RESUMO

Zearalenone (ZEN) is a non-steroidal estrogenic mycotoxin produced by fungi on stored grains. The earlier detection methods used for ZEN rely on expensive equipment, time-consuming sample preparation and temperature sensitive antibodies. The current work, proposed a novel strategy based on ZEN aptamer labeled with amine-functionalized magnetic nanoparticle (MNPs) as a capture probe and time-resolved fluorescence (TRFL) nanoparticles labeled with complementary DNA (cDNA) as a signal probe. Under the optimized conditions, TRFL intensity at 544 nm was used to measure ZEN (R2 = 0.9920) in the range of 0.001-10 ng mL-1 and limits of detection (LOD) for proposed method was 0.21 pg mL-1. The specificity of bioassay was also determined by using other mycotoxins (OTA, AFB2, DON and Patulin) and results showed that the aptamer are specific to recognize only ZEN. The analytical applications of the present bioassay in maize and wheat samples were also examined and results were compared with existing methods. Based on these findings, it is suggested to use current rapid and simple bioassay for the determination of ZEN in food and agricultural products.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais , Corantes Fluorescentes/química , Contaminação de Alimentos/análise , Nanopartículas de Magnetita/química , Zearalenona/análise , Cério/química , Fluorescência , Corantes Fluorescentes/síntese química , Fluoretos/química , Nanopartículas/química , Tamanho da Partícula , Propriedades de Superfície , Térbio/química , Fatores de Tempo , Triticum/química , Ítrio/química , Zea mays/química
20.
PLoS One ; 13(3): e0193584, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29505591

RESUMO

A novel and simple method for detecting 6 zearalenones in animal feed using liquid chromatography coupled with triple quadrupole mass spectrometry (LC-MS/MS) and immunoaffinity columns (IAC) was developed. The chromatographic peaks of the 6 zearalenones were successfully identified by comparing their retention times and mass spectrum with reference standards. The mobile phase was composed of mobile phase A (water) and B (0.5% formic acid in ACN). Method validation was performed with linearity, sensitivity, selectivity, accuracy and precision. The limits of detection (LODs) for the instrument used to study zearalenones ranged from 0.3 to 1.1 µg/kg, and the limits of quantification (LOQs) ranged from 1.0 to 2.2 µg/kg. Average recoveries of the 6 zearalenones ranged from 82.5% to 106.4%. Method replication resulted in intra-day and inter-day peak area variation of <3.8%. The developed method was specific and reliable and is suited for the routine analysis of zearalenones in animal feed.


Assuntos
Ração Animal/análise , Cromatografia de Afinidade/métodos , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Zearalenona/análise , Limite de Detecção , Zearalenona/química
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