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1.
Anal Chem ; 96(42): 16842-16853, 2024 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-39388602

RESUMEN

Limitations in the sensitivity, linear detection range, and cross-reaction of lateral flow immunoassays mainly hamper their application in rapid screening for multiple targets. In this work, we designed a new time-resolved fluorescence immunoassay (TRFIA) platform to overcome these limitations. This platform uses europium chelate polystyrene (PS@Eu) nanoparticles conjugated with monoclonal antibodies to sense multiple mycotoxins. We employed a competitive TRFIA protocol in which the conjugated PS@Eu was used on the surfaces of photonic microbead arrays (PMAs). The TRFIA signal of PMAs on the pad was recorded with the digital time-resolved fluorescence reader. The developed TRFIA shows wide detection linear ranges (0.01-1000 ng/mL for DON, 0.1-100 ng/mL for OTA, and 0.01-100 ng/mL for AFB1), low limits of detection (LODs) (7.9 pg/mL for DON, 18 pg/mL for OTA, and 7.7 pg/mL for AFB1), good specificity, good recovery ratios (76.68-117.26%), and good reproducibility in grain samples. The simulated fluorescence enhancement effect of PMA indicated that the electric field distribution on the surface of PS@Eu on PMA is twice higher than that on the surface of PS@Eu. The new TRFIA for three kinds of mycotoxins was 1000-fold more sensitive than the classical TRFIA, and it has great potential application in rapid screening for multiple targets.


Asunto(s)
Micotoxinas , Fotones , Poliestirenos , Micotoxinas/análisis , Poliestirenos/química , Europio/química , Límite de Detección , Inmunoensayo/métodos , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/química , Fluorescencia , Factores de Tiempo , Tricotecenos/análisis , Ocratoxinas/análisis , Aflatoxina B1/análisis , Aflatoxina B1/inmunología , Nanopartículas/química
2.
Toxins (Basel) ; 16(9)2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39330855

RESUMEN

We conducted a comprehensive examination of liquid mycotoxin reference standards. A total of 30 different standards were tested, each containing 10 samples of three distinct substances: Aflatoxin B1, Deoxynivalenol, and Zearalenone. The standards were sourced from 10 different global market leading manufacturers. To facilitate comparison, all the standard sets were adjusted to the same concentration level. The standards were analyzed using the techniques LC-MS/MS, HPLC-DAD, and LC-HRMS to assess their quality attributes. Regarding the validation of the reference values, it was observed that 30% of the suppliers provided reference standards that were either below the lower acceptance limit or above the higher acceptance limit, confirmed by both the LC-MS/MS and HPLC-DAD methods. Furthermore, a total of 12 impurities were found in the DON standards, 10 in the AFB1 standards, and 8 in the ZON standards, distributed across all the suppliers. Therefore, this study suggests relevant adjustments to the ISO 17034 standard, proposing that the purity of a raw material should be uniformly based on q-NMR analysis, as most manufacturers state the purity of their certificates is determined using HPLC-UV or LC-MS/MS. Liquid standards with a shelf life of ≤1 year should not exceed an uncertainty of 3%. Standards that have a longer shelf life should not have more than 5% uncertainty. This study also emphasizes the importance of stability. The standards should undergo continuous long-term monitoring; otherwise, products may exhibit a target value of only 80%, as seen in one instance. It is also recommended to include proof of HPLC and LC-MS/MS analyses on the certificate of each released batch of a final product.


Asunto(s)
Aflatoxina B1 , Estándares de Referencia , Espectrometría de Masas en Tándem , Tricotecenos , Zearalenona , Tricotecenos/análisis , Zearalenona/análisis , Aflatoxina B1/análisis , Cromatografía Líquida de Alta Presión , Contaminación de Alimentos/análisis , Micotoxinas/análisis , Cromatografía Liquida
3.
Langmuir ; 40(40): 20954-20965, 2024 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-39344816

RESUMEN

In this study, we propose a novel label-free detection strategy based on surface-enhanced Raman spectroscopy (SERS) for detecting deoxynivalenol (DON) and nivalenol (NIV), analyzing the interactions between these fungal toxins and Ag/Au substrates using density functional theory (DFT). The DFT calculation results indicate that the oxygen atoms in DON and NIV molecules exhibit high electronegativity, suggesting that they can serve as active sites in interaction with the metal surfaces in the SERS effect. By constructing DON/NIV-Ag6/Au6 complex models and evaluating their binding energies, we demonstrate the formation of stable complexes, showing characteristic frequency shifts, broadening, and selective enhancement in theoretical Raman spectra. The results indicate that the structural differences between DON and NIV lead to significant variations in the characteristic frequencies of their theoretical SERS spectra, providing a reproducible and interference-resistant method for the label-free detection of these fungal toxins. This work enhances the understanding of molecular-substrate interactions in SERS effects and provides a theoretical basis for the application of label-free SERS sensing strategies based on characteristic frequency shifts.


Asunto(s)
Teoría Funcional de la Densidad , Oro , Plata , Espectrometría Raman , Tricotecenos , Plata/química , Espectrometría Raman/métodos , Oro/química , Tricotecenos/análisis , Tricotecenos/química
4.
Mikrochim Acta ; 191(10): 588, 2024 09 10.
Artículo en Inglés | MEDLINE | ID: mdl-39256210

RESUMEN

Different morphological Cu2O nanoparticles including cube, truncated cube, and octahedron were successfully prepared by a selective surface stabilization strategy. The prepared cube Cu2O exhibited superior peroxidase-like activity over the other two morphological Cu2O nanoparticles, which can readily oxidize 3,3',5,5'-tetramethylbenzidine (TMB) to form visually recognizable color signals. Consequently, a sensitive and simple colorimetric biosensor was proposed for deoxynivalenol (DON) detection. In this biosensor, the uniform cube Cu2O was employed as the vehicle to label the antibody for the recognition of immunoreaction. The sensing strategy showed a detection limit as low as 0.01 ng/mL, and a wide linear range from 2 to 100 ng/mL. Concurrently, the approximate DON concentration can be immediately and conveniently observed by the vivid color changes. Benefiting from the high sensitivity and selectivity of the designed biosensor, the detection of DON in wheat, corn, and tap water samples was achieved, suggesting the bright prospect of the biosensor for the convenient and intuitive detection of DON in actual samples.


Asunto(s)
Bencidinas , Técnicas Biosensibles , Colorimetría , Cobre , Límite de Detección , Nanopartículas del Metal , Tricotecenos , Zea mays , Tricotecenos/análisis , Tricotecenos/inmunología , Colorimetría/métodos , Cobre/química , Técnicas Biosensibles/métodos , Bencidinas/química , Zea mays/química , Nanopartículas del Metal/química , Triticum/química , Peroxidasa/química , Anticuerpos Inmovilizados/inmunología , Contaminación de Alimentos/análisis
5.
Int J Mol Sci ; 25(17)2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39273480

RESUMEN

The quality of food is one of the emergent points worldwide. Many microorganisms produce toxins that are harmful for human and animal health. In particular, mycotoxins from Fusarium fungi are strictly controlled in cereals. Simple and robust biosensors are necessary for 'in field' control of the crops and processed products. Nucleic acid-based sensors (aptasensors) offer a new era of point-of-care devices with excellent stability and limits of detection for a variety of analytes. Here we report the development of a surface-enhanced Raman spectroscopy (SERS)-based aptasensor for the detection of T-2 and deoxynivalenol in wheat grains. The aptasensor was able to detect as low as 0.17% of pathogen fungi in the wheat grains. The portable devices, inexpensive SERS substrate, and short analysis time encourage further implementation of the aptasensors outside of highly equipped laboratories.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Espectrometría Raman , Tricotecenos , Triticum , Espectrometría Raman/métodos , Tricotecenos/análisis , Aptámeros de Nucleótidos/química , Técnicas Biosensibles/métodos , Triticum/microbiología , Triticum/química , Toxina T-2/análisis , Fusarium , Contaminación de Alimentos/análisis
6.
Food Res Int ; 195: 114987, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39277249

RESUMEN

Rice plays an important role in the daily diet in China and therefore its quality and safety have been of great concern. However, few systematic studies have investigated Fusarium community and toxins in rice grains. Here, we collected 1381 rice samples from Jiangsu Province in eastern China and found a higher frequency of zearalenone (ZEN), deoxynivalenol (DON), fumonisins (FBs), and beauvericin (BEA). The positive samples were individually contaminated with a minimum of one and a maximum of ten toxins. Fusarium was isolated and identified as the major fungus, which exhibited temporal and geographical distribution. The most prevalent species complexes within this genus were Fusarium incarnatum-equiseti species complex (FIESC), Fusarium fujikuroi species complex (FFSC), and Fusarium sambucinum species complex (FSAMSC). Nevertheless, the amplicon sequence analysis revealed a low relative abundance of Fusarium in the rice panicles, and the fungal community exhibited an irregular change along with the symptom's emergence. In vitro toxigenic profiles of Fusarium strains showed significant complexity and specificity depending on the type and content. FIESC strains were non-pathogenic to wheat heads and weakly pathogenic to maize ears, respectively, accumulating lower amounts of toxins than F. asiaticum and F. fujikuroi. There was no significant variation in the ability to cause panicle blight in rice among the various species tested. Our study provides detailed information about the contamination of Fusarium toxins and community in rice after harvest. This information is valuable for understanding the relationship between Fusarium and rice and for developing effective control strategies.


Asunto(s)
Contaminación de Alimentos , Fusarium , Micotoxinas , Oryza , Fusarium/aislamiento & purificación , Fusarium/genética , Oryza/microbiología , Contaminación de Alimentos/análisis , Micotoxinas/análisis , China , Depsipéptidos/análisis , Tricotecenos/análisis , Microbiología de Alimentos , Zearalenona/análisis , Fumonisinas/análisis
7.
PLoS One ; 19(8): e0309662, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39208293

RESUMEN

Silage has been identified as a source of different microbial toxins, that may impair farm animal health and productivity as human health can also be compromised. In this sense, the aim of this study was to determine the impact of silage additives on the concentrations of deoxynivalenol (DON) and zearalenone (ZEN) mycotoxins and, eventually, to evaluate the hygienic quality of orchardgrass (Dactylis glomerata L.) silage based on the concentration of them compared to control silage. This study evaluated the influence of biological and chemical additives used in six different varieties of orchardgrass silage on DON and ZEN mycotoxin contents for the first time. The content of both fusariotoxins (DON and ZEN) in fresh matter and grass silage were below the threshold stipulated by the European Commission. The concentration of DON ranges from ~21.86 to 37.26 ng/kg, ~10.21 to 15 ng/kg, ~20.72 to 29.14 ng/kg; and ZEN range from ~3.42 to 7.87 ng/kg, ~3.85 to 8.62 ng/kg and ~2.15 to 5.08 ng/kg, in control, biological and chemical silages, respectively. In general, the biological additive was more efficient for preventing DON contamination, whereas the chemical additive was more efficient for preventing ZEN contamination in grass silage. In summary, the results obtained in this work demonstrate that biological and chemical additives can inhibit fungal growth and mycotoxin production on Dactylis glomerata L. silage and whose use could prevent animal and human diseases.


Asunto(s)
Dactylis , Micotoxinas , Ensilaje , Tricotecenos , Zearalenona , Ensilaje/análisis , Ensilaje/microbiología , Zearalenona/análisis , Zearalenona/metabolismo , Tricotecenos/metabolismo , Tricotecenos/análisis , Micotoxinas/biosíntesis , Micotoxinas/análisis , Dactylis/metabolismo , Animales
8.
J Hazard Mater ; 477: 135366, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39088943

RESUMEN

Deoxynivalenol-3-glucoside (D3G), the masked form of the important mycotoxin deoxynivalenol (DON), displays potential toxicity but is difficult to control owing to the lack of rapid detection methods. Herein, an innovative molecularly imprinted polymer (MIP)-based electrochemical sensor was developed for the rapid detection of D3G. MIP, an efficient recognition element for D3G, was electropolymerized using o-phenylenediamine based on a surface functional monomer-directing strategy for the first time. CeO2, which contains both Ce3+ and Ce4+ oxidation states, was introduced as a nanozyme to catalyze H2O2 reduction, while Mn doping generated more oxygen vacancies and considerably improved the catalytic activity. Mn-CeO2 also served as a promising substrate material because of its large surface area and excellent conductivity. Under optimal conditions, a good linear relationship was observed for D3G detection over the concentration range of 0.01-50 ng/mL. The proposed sensor could detect D3G down to 0.003 ng/mL with excellent selectivity, even distinguishing its precursor DON in complex samples. The sensor exhibited acceptable stability with high reproducibility and accuracy, and could successfully determine D3G in grain samples. To the best of our knowledge, this is the first electrochemical sensing platform for rapid D3G detection that can easily be expanded to other masked mycotoxins.


Asunto(s)
Cerio , Técnicas Electroquímicas , Manganeso , Tricotecenos , Tricotecenos/análisis , Tricotecenos/química , Cerio/química , Manganeso/química , Polímeros Impresos Molecularmente/química , Impresión Molecular , Polímeros/química , Reproducibilidad de los Resultados , Grano Comestible/química , Límite de Detección , Glucósidos/química , Glucósidos/análisis , Contaminación de Alimentos/análisis , Peróxido de Hidrógeno/química , Peróxido de Hidrógeno/análisis
9.
Food Res Int ; 192: 114784, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39147488

RESUMEN

The distribution of deoxynivalenol (DON) and its derivatives 3-acetyldeoxynivalenol (3-Ac-DON) and 15-acetyldeoxynivalenol (15-Ac-DON) throughout the wheat processing chain were systemically evaluated by one-to-one corresponding studies of the whole processing chain. DON and its derivatives were determined by liquid chromatography-mass spectrometry (LC-MS/MS) in wheat grains and corresponding wheat bran, wheat flour, and semi-finished and finished wheat flour-based products. This investigation showed that wheat grain processing to wheat flour significantly decreased the levels of DON by approximately 52.7%-68.2%. Wheat flour processing of wheat flour-based products decreased the DON concentration by approximately 7.0%-70.6%. Among the processing methods, biscuit making showed the largest reduction (70.6%). The co-occurrence frequency of DON with low levels of 3-Ac-DON and 15-Ac-DON was significantly greater in wheat grains and wheat bran than in wheat flour. For wheat flour-based products, only the distribution pattern of 3-Ac-DON was observable in processed wheat flour products prepared using grains heavily contaminated with DON. In China, to the best of our knowledge, the processing factors (PFs) of DON in wheat flour and wheat flour-based products were systematically evaluated for the first time. The average PF of DON was 0.35 for wheat flour and the average PFs were 0.37-0.84 for wheat flour-based products, with biscuits having the smallest PF (0.37), indicating DON significantly decreasing in biscuit making. Furthermore, dietary exposure assessment of DON indicated an acceptable overall health risk in Chinese consumers, with the highest exposure being observed in infants and young children. This study provides important references for classified management of DON limits in wheat and its various products in China.


Asunto(s)
Harina , Contaminación de Alimentos , Manipulación de Alimentos , Espectrometría de Masas en Tándem , Tricotecenos , Triticum , Tricotecenos/análisis , Triticum/química , Harina/análisis , Contaminación de Alimentos/análisis , Manipulación de Alimentos/métodos , Cromatografía Liquida , Humanos , China
10.
Food Chem ; 459: 140341, 2024 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-39121528

RESUMEN

A highly sensitive method based on MBs-cDNA@Apt-AuNCs519 was developed for deoxynivalenol (DON) detection in wheat. The MBs-cDNA@Apt-AuNCs519 was established using green emission gold nanoclusters (AuNCs519) with aggregation-induced emission properties as signal probes and combining amino-modified DON-aptamer (Apt), biotin-modified DNA strand (the partially complementary to Apt (cDNA)), and streptavidin-modified magnetic beads (MBs). The Apt-AuNCs519 were well connected with MBs-cDNA without DON but dissociated from MBs-cDNA@Apt-AuNCs519 with the addition of DON, leading to a noticeable reduction in the fluorescent intensity of the aptasensor. Moreover, this fluorescence aptasensor showed two linear relationships in the concentration range of 0.1-50 ng/mL and 50-5000 ng/mL with a limit of detection of 3.73 pg/mL with good stability, reproducibility and specificity. The results were consistent with high-performance liquid chromatography and enzyme-linked immunosorbent assay methods, further indicating the potential of this method for accurate trace detection of DON in wheat.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Contaminación de Alimentos , Oro , Nanopartículas del Metal , Tricotecenos , Triticum , Tricotecenos/química , Tricotecenos/análisis , Oro/química , Triticum/química , Aptámeros de Nucleótidos/química , Nanopartículas del Metal/química , Contaminación de Alimentos/análisis , Técnicas Biosensibles/instrumentación , Técnicas Biosensibles/métodos , Límite de Detección , Fluorescencia
11.
Food Chem ; 460(Pt 2): 140550, 2024 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-39142026

RESUMEN

An emerging fluorescent ratiometric aptasensor based on gold nanoclusters (AuNCs) with aggregation-induced emission (AIE) properties was prepared and studied for deoxynivalenol (DON) detection. The ratiometric aptasensor used red fluorescent AuNCs620 labelled with DON aptamer (Apt-AuNCs620) as an indicator and green fluorescent AuNCs519 modified by complementary DNA (cDNA) and magnetic beads (MBs) as internal reference, namely MBs-cDNA-AuNCs519. Under the optimal conditions, the aptasensor exhibited two good linear ranges of 0.1-50 and 50-5000 pg/mL for DON detection with coefficient of determination (R2) of 0.9937 and 0.9928, respectively, and the low detection limit (LOD) of 4.09 pg/mL was achieved. Furthermore, this aptasensor was feasible to detect DON in positive wheat samples, and the results were in line with those from HPLC and ELISA, thus providing a promising route to detect DON with high sensitivity in cereals, even for other mycotoxins by replacing the suitable aptamer and cDNA.


Asunto(s)
Aptámeros de Nucleótidos , Contaminación de Alimentos , Oro , Límite de Detección , Tricotecenos , Triticum , Tricotecenos/análisis , Tricotecenos/química , Aptámeros de Nucleótidos/química , Oro/química , Triticum/química , Contaminación de Alimentos/análisis , Técnicas Biosensibles , Nanopartículas del Metal/química , Colorantes Fluorescentes/química , Fluorescencia , Espectrometría de Fluorescencia
12.
Toxins (Basel) ; 16(8)2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39195782

RESUMEN

Mycotoxin emergence and co-occurrence trends in Canadian grains are dynamic and evolving in response to changing weather patterns within each growing season. The mycotoxins deoxynivalenol and zearalenone are the dominant mycotoxins detected in grains grown in Eastern Canada. Two potential emerging mycotoxins of concern are sterigmatocystin, produced by Aspergillus versicolor, and diacetoxyscirpenol, a type A trichothecene produced by a number of Fusarium species. In response to a call from the 83rd Joint Expert Committee on Food Additives and Contaminants, we conducted a comprehensive survey of samples from cereal production areas in Ontario, Canada. Some 159 wheat and 160 corn samples were collected from farms over a three-year period. Samples were extracted and analyzed by LC-MS/MS for 33 mycotoxins and secondary metabolites. Ergosterol was analyzed as an estimate of the overall fungal biomass in the samples. In wheat, the ratio of DON to its glucoside, deoxynivalenol-3-glucoside (DON-3G), exhibited high variability, likely attributable to differences among cultivars. In corn, the ratio was more consistent across the samples. Sterigmatocystin was detected in some wheat that had higher concentrations of ergosterol. Diacetoxyscirpenol was not detected in either corn or wheat over the three years, demonstrating a low risk to Ontario grain. Overall, there was some change to the mycotoxin profiles over the three years for wheat and corn. Ongoing surveys are required to reassess trends and ensure the safety of the food value chain, especially for emerging mycotoxins.


Asunto(s)
Contaminación de Alimentos , Micotoxinas , Triticum , Zea mays , Zea mays/microbiología , Zea mays/química , Triticum/microbiología , Triticum/química , Ontario , Micotoxinas/análisis , Contaminación de Alimentos/análisis , Tricotecenos/análisis , Espectrometría de Masas en Tándem , Ergosterol/análisis
13.
Int J Food Microbiol ; 425: 110876, 2024 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-39173288

RESUMEN

The diversity of fungi in wheat with different deoxynivalenol (DON) content at various periods post-harvest and in the environment of storage were investigated. The changes in DON content were measured with ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS), and an amplicon sequence analysis of fungi was performed in traditional storage structures using high-throughput sequencing. The changes in temperature, humidity, and CO2 concentration were collected by sensors. In addition, we analyzed principal component analysis, species composition, species differences, and community differences of fungi. There was an obvious separation of the fungal communities under different storage conditions and times. Many fungal genera were gradually decreasing during storage and were eventually undetectable, and many fungal genera that were undetectable at first gradually increased during storage and even became dominant fungal genera. The competition between fungi was fierce. The competition between fungi were affected by the presence of DON. As the initial DON content increased, the contribution of inter-group differences became more obvious. The temperature, humidity, and CO2 concentration of wheat in the silo's environment changed with extended storage time. The content of DON decreased with extended storage time. We had investigated the changes in DON content and their correlation with the changes in fungal communities and environmental factors, which showed a high degree of correlation. This study offers theoretical justification for optimizing safe wheat grain in traditional storage conditions.


Asunto(s)
Almacenamiento de Alimentos , Hongos , Triticum , Triticum/microbiología , Hongos/clasificación , Hongos/genética , Hongos/aislamiento & purificación , Secuenciación de Nucleótidos de Alto Rendimiento , Tricotecenos/análisis , Micobioma , Contaminación de Alimentos/análisis , Temperatura , Espectrometría de Masas en Tándem , Microbiología de Alimentos , Cromatografía Líquida de Alta Presión
14.
Anal Bioanal Chem ; 416(22): 4999-5012, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39093417

RESUMEN

Oat products have gained widespread recognition as a health food due to their rich and balanced nutritional profile and convenience. However, the unique matrix composition of oats, which differs significantly from other cereals, presents specific challenges for mycotoxin analysis. This study presents an ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method enhanced with an innovative egg white gel pretreatment for the simultaneous analysis of 13 regulated and unregulated trichothecenes in oats. The method demonstrated excellent performance with high accuracy (> 87.5%), repeatability (< 5.7%), and reproducibility (< 8.1%). Analysis of 100 commercial oat products revealed a concerning detection rate (78%) for at least one of the 11 trichothecenes investigated. Notably, deoxynivalenol, exceeding the standard limit in 2% of samples, exhibited the highest detection rate (62%). Additionally, concerning co-occurrence patterns and positive correlations were observed, highlighting potential synergistic effects. The first-time detection of unregulated mycotoxins (T-2 triol, 4,15-diacetoxyscirpenol, 15-acetoxyscirpenol, and neosolaniol) underscores the need for comprehensive monitoring. This method, while developed for oats, shows potential for broader application to other cereals, though further investigation and confirmation are necessary. These findings suggest a potentially underestimated risk of trichothecenes in oats, necessitating continuous monitoring to ensure consumer safety.


Asunto(s)
Avena , Contaminación de Alimentos , Límite de Detección , Espectrometría de Masas en Tándem , Tricotecenos , Avena/química , Espectrometría de Masas en Tándem/métodos , Cromatografía Líquida de Alta Presión/métodos , Tricotecenos/análisis , Contaminación de Alimentos/análisis , Geles/química , Reproducibilidad de los Resultados
15.
ACS Appl Mater Interfaces ; 16(29): 37748-37756, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-38990678

RESUMEN

Multitarget assay has always been a hot topic in electrochemiluminescence (ECL) methods. Herein, a "on-off-on" ECL aptasensor was developed for the ultrasensitive and sequential detection of possible biological warfare agents, deoxynivalenol (DON) and abrin (ABR). As a luminophore, polymer dots (Pdots) with aggregation-induced emission exhibit high ECL efficiency in the aptasensor, i.e., the signal "on" state. The DON assays mainly depend on ECL quenching due to the efficient quenching effect between ferrocene-H2-ferrocene (Fc-H2-Fc) and Pdots, i.e., the signal "off" state. When the aptasensor is incubated with the oligonucleotide sequence S2 to replace Fc-H2-Fc, obvious ECL recovery occurs, i.e., the signal "on" state, which can be used to sequentially detect ABR. The limit of detection (LOD) for DON is 0.73 fg·mL-1 in the range of 5.0 to 50 ng·mL-1; and the LOD for ABR is ∼0.38 pg·mL-1 in the range of 1.25 pg·mL-1 to 1.25 µg·mL-1. The as-designed ECL aptasensor exhibits good stability and reproducibility, high specificity, and favorable practicality. Therefore, this work provides a new approach for assays of DON and ABR in food safety and can be used as a model to design an ultrasensitive ECL biosensor for multitarget detection.


Asunto(s)
Técnicas Biosensibles , Técnicas Electroquímicas , Mediciones Luminiscentes , Polímeros , Puntos Cuánticos , Tricotecenos , Técnicas Biosensibles/métodos , Mediciones Luminiscentes/métodos , Técnicas Electroquímicas/métodos , Polímeros/química , Tricotecenos/análisis , Puntos Cuánticos/química , Abrina/análisis , Límite de Detección , Aptámeros de Nucleótidos/química
16.
Anal Methods ; 16(30): 5231-5238, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39007341

RESUMEN

Deoxynivalenol (DON) has drawn considerable attention for its obvious pathogenicity and wide use in agro-products, which cause a potential threat to human health. In this work, an electrochemical immunosensor is developed for the highly sensitive and selective detection of DON in wheat flour using AuNPs-BP-MWCNTs-COOH and antibodies. The AuNPs-BP-MWCNTs-COOH nanocomposite was prepared via an in situ reduction reaction and ultrasonic-assisted liquid-phase exfoliation. The nanocomposite exhibits a larger surface area, decent stability, excellent electron transfer capability, good protein binding capability and prominent specificity. The plentiful carboxyl group on the nanocomposite can bind to the amino group of the antibody, and AuNPs have an affinity for the sulfhydryl group of the antibody, which makes it feasible for the nanocomposite to load the antibody. The peak currents are plotted against the logarithm of DON concentration from 0.002 to 80 ng mL-1 with a limit of detection (LOD) of 0.5 pg mL-1. This approach establishes an effective label-free immunosensor platform for the detection of DON with high sensitivity and selectivity in various food and agricultural products.


Asunto(s)
Técnicas Electroquímicas , Harina , Oro , Nanopartículas del Metal , Tricotecenos , Triticum , Tricotecenos/análisis , Tricotecenos/inmunología , Harina/análisis , Triticum/química , Nanopartículas del Metal/química , Oro/química , Técnicas Electroquímicas/métodos , Inmunoensayo/métodos , Técnicas Biosensibles/métodos , Límite de Detección , Nanotubos de Carbono/química , Contaminación de Alimentos/análisis , Nanocompuestos/química
17.
Food Addit Contam Part B Surveill ; 17(3): 261-274, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38982744

RESUMEN

Maize grain samples collected from 129 small-scale farmers' stores in southern and southwestern Ethiopia were analysed by LC-MS/MS for a total of 218 mycotoxins and other fungal metabolites of which 15% were regulated mycotoxins. Mycotoxins produced by Penicillium, Aspergillus, and Fusarium accounted for 31%, 17%, and 12% of the metabolites, respectively. Most of the current samples were contaminated by masked and/or emerging mycotoxins with moniliformin being the most prevalent one, contaminating 93% of the samples. Each sample was co-contaminated by 3 to 114 mycotoxins/fungal metabolites. Zearalenone, fumonisin B1, and deoxynivalenol were the dominant mycotoxins, occurring in 78%, 61%, and 55% of the samples with mean concentrations of 243, 429, and 530 µg/kg, respectively. The widespread co-occurrence of several mycotoxins in the samples may pose serious health risks due to synergistic/additional effects.


Asunto(s)
Contaminación de Alimentos , Fumonisinas , Micotoxinas , Espectrometría de Masas en Tándem , Zea mays , Zea mays/química , Zea mays/microbiología , Etiopía , Micotoxinas/análisis , Contaminación de Alimentos/análisis , Fumonisinas/análisis , Humanos , Zearalenona/análisis , Fusarium/química , Fusarium/metabolismo , Tricotecenos/análisis , Penicillium , Aspergillus , Almacenamiento de Alimentos , Cromatografía Liquida/métodos , Ciclobutanos
18.
Mycotoxin Res ; 40(4): 591-603, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39028531

RESUMEN

Environmental factors influence fungal growth and mycotoxin production in stored grains. However, the concentrations of free mycotoxins and their conjugates and how they are impacted by different interacting environment conditions have not been previously examined. The objectives of this study were to examine the impact of storage conditions (0.93-0.98 aw) and temperature (20-25 °C) on (a) the concentrations of deoxynivalenol and zearalenone and their respective glucosides/conjugates and (b) the concentrations of emerging mycotoxins in both naturally contaminated and irradiated wheat grains inoculated with Fusarium graminearum. Contaminated samples were analysed for multiple mycotoxins using Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS). Method validation was performed according to the acceptable performance criteria set and updated by the European Commission regulations No. 2021/808/EC. As an important conjugate of deoxynivalenol, the concentrations of deoxynivalenol-3-glucoside were significantly different from its precursor deoxynivalenol at 0.93 aw (22% moisture content- MC) at 25 °C in the naturally contaminated wheat with a ratio proportion of 56:44% respectively. The high concentrations of deoxynivalenol-3-glucoside could be influenced by the wheat's variety and/or harvested season/fungal strain type/location. Zeralenone-14-sulfate concentrations were surprisingly three times higher than Zearalenone in the naturally contaminated wheat at 0.98 aw (26% MC) at both temperatures. Emerging mycotoxins such as moniliformin increased with temperature rise with the highest concentrations at 0.95 aw and 25 °C. These findings highlight the influence and importance of storage aw x temperature conditions on the relative presence of free vs conjugated mycotoxins which can have implications for food safety.


Asunto(s)
Contaminación de Alimentos , Fusarium , Espectrometría de Masas en Tándem , Temperatura , Tricotecenos , Triticum , Zearalenona , Triticum/química , Triticum/microbiología , Zearalenona/análisis , Tricotecenos/análisis , Cromatografía Liquida , Contaminación de Alimentos/análisis , Almacenamiento de Alimentos , Glucósidos/análisis , Grano Comestible/química , Grano Comestible/microbiología , Micotoxinas/análisis
19.
Mycotoxin Res ; 40(4): 547-558, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38990416

RESUMEN

Mycotoxins, such as aflatoxin B1 (AFB1), deoxynivalenol (DON), fumonisins (FBs), ochratoxin A (OTA), T-2 toxin (T-2), and zearalenone (ZEN), can contaminate animal feeds and pose risks to animal health and production performance. These mycotoxins are commonly found in cereals and grains, with the increased use of cereals in pet food, there is a rising concern about mycotoxin contamination among pet owners. To address this, we analyzed imported brands of feline and canine food from the Chinese market produced in 2021-2022. Ninety-three samples were analyzed, comprising 45 feline food and 48 canine food samples. Among them, 14 were canned food and 79 were dry food. The results indicate that AFB1, DON, FBs, OTA, T-2, and ZEN occurred in 32.26%, 98.92%, 22.58%, 73.12%, 55.91%, and 7.53% of the samples, respectively. The most prevalent mycotoxin was DON, followed by OTA, T-2, AFB1, and FBs, whereas ZEN was less frequently detected. The mean concentrations of the six mycotoxins in pet feed samples were 3.17 µg/kg for AFB1, 0.65 mg/kg for DON, 2.15 mg/kg for FBs, 6.27 µg/kg for OTA, 20.00 µg/kg for T-2, and 30.00 µg/kg for ZEN. The levels of mycotoxins were generally below the limits of the Pet Feed Hygiene Regulations of China and the EU. Notably, a substantial majority of the pet food samples (88 out of 93) were contaminated by two or more mycotoxins. AFB1, FBs, OTA, and ZEN occurred slightly more often in feline food than in canine food. Except for OTA, the contamination rates for the other five mycotoxins in canned food were lower than those in dry food. Moreover, except for AFB1, the levels of the other five mycotoxins in canned foods were lower than those in dry foods. This study highlights the widespread contamination of pet foods with mycotoxins, which poses a significant risk to pets from continuous exposure to multiple mycotoxins.


Asunto(s)
Alimentación Animal , Contaminación de Alimentos , Micotoxinas , Animales , Gatos , Micotoxinas/análisis , Alimentación Animal/análisis , Alimentación Animal/microbiología , Contaminación de Alimentos/análisis , Perros , China , Tricotecenos/análisis , Aflatoxina B1/análisis , Ocratoxinas/análisis
20.
Mycotoxin Res ; 40(4): 631-639, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39078561

RESUMEN

The debranning process, at an industrial scale, was applied to grains of two wheat cultivars to determine its effect on Fusarium mycotoxin content and antioxidant activity. Grain samples from the BRS Marcante and BRS Reponte wheat cultivars, naturally contaminated by Fusarium, were used in the study. The dry wheat samples were processed on the polisher once or twice and evaluated by hardness index, chemical composition (moisture, protein, and ash), deoxynivalenol (DON) and zearalenone (ZON) levels, phenolic content, and antioxidant activity. In the BRS Marcante cultivar, the debranning process only slightly reduced the DON and ZON contents in whole-wheat flours compared with the previous cleaning treatment (no-debranned). In the BRS Reponte cultivar, the DON concentration decreased by 36% at a debranning ratio of 5%, obtained by polishing, compared with prior cleaning treatment (no-debranned). In addition, the polishing reduced the ZON level by 56% compared with the cleaned wheat. The debranning process did not reduce the antioxidant capacity. Therefore, debranning is a suitable technology to obtain safer and healthier food by minimizing the mycotoxin content and retaining antioxidant capacity.


Asunto(s)
Antioxidantes , Fusarium , Micotoxinas , Fenoles , Triticum , Triticum/química , Antioxidantes/análisis , Fenoles/análisis , Micotoxinas/análisis , Zearalenona/análisis , Tricotecenos/análisis , Manipulación de Alimentos/métodos , Contaminación de Alimentos/análisis , Harina/análisis
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