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1.
J Chromatogr A ; 1724: 464915, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38663319

RESUMO

Efficient enrichment of trace zearalenone (ZEN) from the complex traditional Chinese medicine (TCM) samples is quite difficult, but of great significance for TCM quality control. Herein, we reported a novel magnetic solid phase extraction (MSPE) strategy for ZEN enrichment using the amino- and hydroxyl dual-functionalized magnetic microporous organic network (Fe3O4@MON-NH2-OH) as an advanced adsorbent combined with the high-performance liquid chromatography (HPLC) determination. Efficient extraction of ZEN was achieved via the possible hydrogen bonding, hydrophobic, and π-π interactions between Fe3O4@MON-NH2-OH and ZEN. The adsorption capacity of Fe3O4@MON-NH2-OH for ZEN was 215.0 mg g-1 at the room temperature, which was much higher than most of the reported adsorbents. Under the optimal condition, the developed Fe3O4@MON-NH2-OH-MSPE-HPLC method exhibited wide linear range (5-2500 µg L-1), low limits of detection (1.4-35 µg L-1), less adsorbent consumption (5 mg), and large enhancement factor (95) for ZEN. The proposed method was successfully applied to detect trace ZEN from 10 kinds of real TCM samples. Conclusively, this work demonstrates the Fe3O4@MON-NH2-OH can effectively extract trace ZEN from the complex TCM matrices, which may open up a new way for the application of MONs in the enrichment and extraction of trace contaminants or active constituents from the complex TCM samples.


Assuntos
Medicamentos de Ervas Chinesas , Limite de Detecção , Extração em Fase Sólida , Zearalenona , Cromatografia Líquida de Alta Pressão/métodos , Zearalenona/análise , Zearalenona/química , Zearalenona/isolamento & purificação , Extração em Fase Sólida/métodos , Adsorção , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicina Tradicional Chinesa , Porosidade , Nanopartículas de Magnetita/química
2.
J Pharm Pharmacol ; 74(3): 446-457, 2022 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-34850064

RESUMO

OBJECTIVES: This study aimed to evaluate endophytic fungi isolated from Tocoyena bullata and Humiria balsamifera plant species for their antimycobacterial and anti-inflammatory activities, focusing on severe pulmonary tuberculosis cases which are often associated with exacerbated inflammation. METHODS: Mycobacterium suspensions were incubated with the samples for 5 days. RAW 264.7 macrophages stimulated with LPS were also incubated with them for 24 h to assess the inhibition of inflammatory mediator production and cytotoxicity. C57BL/6 mice were infected with Mtb M299 and treated for 15 days with lasiodiplodin (Lasio). KEY FINDINGS: Endophytic fungus Sordaria tamaensis, obtained from T. bullata, was the most promising. Its ethanolic extract impaired mycobacterial growth with MIC50 (µg/ml): 1.5 ± 0.6 (BCG), 66.8 ± 0.1 (H37Rv) and 80.0 ± 0.1 (M299). (R)-(+)-Lasio showed MIC50 92.2 ± 1.8 µg/ml (M299). In addition, Lasio was able to inhibit NO, IL-1ß and TNF-α production and was not cytotoxic for macrophages. M. tuberculosis-infected C57BL/6 animals treated by Lasio reduced the number of acid-fast bacilli, lung pathology, leucocyte influx and proinflammatory cytokine production in the lungs. The class IIa fructose 1,6-bisphosphate aldolase was the predicted hypothetical target of Lasio. CONCLUSIONS: (R)-(+)-Lasio stood out as a promising anti-TB compound, exhibiting anti-inflammatory and antimycobacterial effects, as well as low cytotoxicity.


Assuntos
Anti-Inflamatórios/farmacologia , Antituberculosos/farmacologia , Sordariales/química , Zearalenona/análogos & derivados , Animais , Anti-Inflamatórios/isolamento & purificação , Antituberculosos/isolamento & purificação , Células CACO-2 , Humanos , Inflamação/tratamento farmacológico , Lipopolissacarídeos , Macrófagos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Mycobacterium tuberculosis/efeitos dos fármacos , Células RAW 264.7 , Rubiaceae/microbiologia , Sordariales/isolamento & purificação , Tuberculose Pulmonar/tratamento farmacológico , Tuberculose Pulmonar/microbiologia , Zearalenona/isolamento & purificação , Zearalenona/farmacologia
3.
Mikrochim Acta ; 188(8): 246, 2021 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-34235593

RESUMO

Magnetic covalent organic framework nanocomposite denoted as Fe3O4@TAPB-Tp with core-shell structure was fabricated via a simple template-mediated precipitation polymerization method at mild conditions. The polyimine network shell was created through the polymerization of 1,3,5-tris(4-aminophenyl)-benzene (TAPB) and 1,3,5-triformyl-phloroglucinol (Tp) in tetrahydrofuran (THF) by the Schiff-base reaction. Featuring with large specific surface area (163.19 m2 g-1), good solution dispersibility, and high stability, the obtained Fe3O4@TAPB-Tp exhibited high adsorption capacities and fast adsorption for zearalenone and its derivatives (ZEAs). The adsorption isotherms showed multilayer adsorption dominated at low concentration and monolayer adsorption at high concentration between the interface of ZEAs and Fe3O4@TAPB-Tp. With the Fe3O4@TAPB-Tp as sorbent, a magnetic solid-phase extraction-ultrahigh performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was established for simultaneous adsorption and detection of five ZEAs in complex samples. The proposed method displayed favorable linearity, low limits of detection (0.003 ~ 0.018 µg kg-1), and good repeatability (2.37~10.4%). The developed method has been applied for real sample analysis, with recoveries of 81.27~90.26%. These results showed that Fe3O4@TAPB-Tp has a good application potential for the adsorption of ZEAs in food samples. Magnetic covalent organic framework nanocomposite (Fe3O4@TAPB-Tp) were quickly fabricated at mild conditions and used as effective adsorbent for magnetic solid-phase extraction of zearalenone and its derivatives (ZEAs) from food samples prior to ultrahigh performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) analysis.


Assuntos
Nanopartículas de Magnetita/química , Estruturas Metalorgânicas/química , Micotoxinas/análise , Zearalenona/análise , Adsorção , Animais , Derivados de Benzeno/química , Cromatografia Líquida de Alta Pressão , Ovos/análise , Contaminação de Alimentos/análise , Limite de Detecção , Fenômenos Magnéticos , Leite/química , Micotoxinas/química , Micotoxinas/isolamento & purificação , Nanocompostos/química , Floroglucinol/análogos & derivados , Floroglucinol/química , Polimerização , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem , Zea mays , Zearalenona/análogos & derivados , Zearalenona/isolamento & purificação
4.
J Antibiot (Tokyo) ; 74(8): 496-507, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34155352

RESUMO

Resorcylic acid lactones (RALs) with a cis-enone moiety, represented by hypothemycin (1) and (5Z)-7-oxozeaenol (2), are fungal secondary metabolites with irreversible inhibitory activity against protein kinases, with particularly selective activity for inhibition of TAK1 (transforming growth factor beta-activated kinase 1). Gram-scale quantities of these compounds were needed as feedstock for semi-synthesizing RAL-analogues in a step-economical fashion. To do so, this study had three primary goals: identifying fungi that biosynthesized 1 and 2, enhancing their production by optimizing the fermentation conditions on the lab scale, and developing straight forward purification processes. After evaluating 536 fungal extracts via an in-house dereplication protocol, three strains were identified as producing cis-enone RALs (i.e., MSX78495, MSX63935, MSX45109). Screening these fungal strains on three grain-based media revealed enhanced production of 1 by strain MSX78495 on oatmeal medium, while rice medium increased the biosynthesis of 2 by strain MSX63935. Furthermore, the purification processes were improved, moving away from HPLC purification to utilizing two to four cycles of resuspension and centrifugation in small volumes of organic solvents, generating gram-scale quantities of these metabolites readily. In addition, studying the chemistry profiles of strains MSX78495 and MSX63935 resulted in the isolation of ten other RALs (3-12), two radicinin analogues (13-14), and six benzopyranones (15-20), with 19 and 20 being newly described chlorinated benzopyranones.


Assuntos
Resorcinóis/química , Antibacterianos/biossíntese , Antibacterianos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Meios de Cultura , Fermentação , Fungos/metabolismo , Lactonas/química , MAP Quinase Quinase Quinases/antagonistas & inibidores , Conformação Molecular , Inibidores de Proteínas Quinases/farmacologia , Resorcinóis/farmacologia , Estereoisomerismo , Relação Estrutura-Atividade , Zearalenona/análogos & derivados , Zearalenona/biossíntese , Zearalenona/isolamento & purificação
5.
Curr Top Med Chem ; 21(10): 895-907, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33902419

RESUMO

INTRODUCTION: Endophyte is considered a source of natural bioactive secondary metabolites that provides an array of bioactive lead compounds. The present study was aimed to determine the antimicrobial and anti-inflammatory potential of fungal endophytes isolated from Catharanthus roseus. METHODS: A total of seven fungal endophytes crude extract were screened against bacterial pathogens. Of these, Curvularia geniculata CATDLF7 crude extract exhibited the most potent inhibitory activity against bacterial pathogens. Hence, CATDLF7 crude extract was subjected to chromatographic separation. This purification leads to the isolation of six pure compounds (1PS - 6PS). Of these, 3PS was found to be a major constituent and most effective against clinical isolates of methicillin- resistant Staphylococcus aureus (MRSA) with minimum inhibitory concentration (MIC) values ranging from 100 to 200 µg/ml. Based on the spectroscopic data, 3PS was characterized as α,ß- dehydrocurvularin. This compound also showed synergistic interaction with norfloxacin and reduced its MIC up to 32-folds with a fractional inhibitory concentration index (FICI) of 0.09. RESULTS: To understand the possible antibacterial mechanism of action, α,ß-dehydrocurvularin alone (100 µg/ml) exhibited efflux pump inhibitory potential by 0.84 fold decreasing in ethidium bromide (EtBr) fluorescence. In addition, α,ß-dehydrocurvularin inhibited inflammatory cytokines TNF-α and IL-6 production, which is further validated by molecular docking scores -4.921 and -5.641, respectively, for understanding orientation and binding affinity. CONCLUSION: Overall, the results highlighted identifying bioactive compound α,ß-dehydrocurvularin, which could be used as an antimicrobial and anti-inflammatory agent.


Assuntos
Anti-Infecciosos/isolamento & purificação , Anti-Inflamatórios/isolamento & purificação , Catharanthus/química , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Zearalenona/análogos & derivados , Animais , Anti-Infecciosos/farmacologia , Anti-Inflamatórios/farmacologia , Citocinas/metabolismo , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Quimioterapia Combinada , Endófitos/metabolismo , Feminino , Humanos , Interleucina-6/metabolismo , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Camundongos , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Norfloxacino/farmacologia , Extratos Vegetais/farmacologia , Ligação Proteica , Transdução de Sinais , Relação Estrutura-Atividade , Zearalenona/isolamento & purificação , Zearalenona/farmacologia
6.
J Nat Prod ; 84(2): 483-494, 2021 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-33544615

RESUMO

Twelve new hypothemycin-type resorcylic acid lactones, three 10-membered (1-3) and nine 14-membered (4-12), together with seven known analogues (13-19), were obtained from the solid rice-based culture of Podospora sp. G214. Their structures were elucidated utilizing spectroscopic analysis, and the absolute configurations were determined by modified Mosher's method, Mo2(OAc)4-induced electronic circular dichroism experiments, and single-crystal X-ray diffraction. Compounds 1, 5, 10, and 12-19 exhibited potent immunosuppressive activities against concanavalin A-induced T cell proliferation with IC50 values ranging from 6.0 to 25.1 µM and lipopolysaccharide-induced B cell proliferation with IC50 values ranging from 6.2 to 29.1 µM. Further studies revealed that 1 induced apoptosis in activated T cells through the JNK-mediated mitochondrial pathway.


Assuntos
Linfócitos B/efeitos dos fármacos , Imunossupressores/farmacologia , Lactonas/farmacologia , Podospora/química , Linfócitos T/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Células Cultivadas , China , Imunossupressores/isolamento & purificação , Lactonas/isolamento & purificação , Masculino , Camundongos Endogâmicos BALB C , Estrutura Molecular , Raízes de Plantas/microbiologia , Sanguisorba/microbiologia , Baço/citologia , Zearalenona/análogos & derivados , Zearalenona/isolamento & purificação , Zearalenona/farmacologia
7.
Food Chem ; 347: 128977, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33497872

RESUMO

A multi-channel magnetic bead micro-probes assay (MBPA) based on indirect competitive principle was developed for high-throughput detection of zearalenone (ZEA) in edible and medicinal Coix seed. This strategy introduced magnetic beads as the carriers, the specific primary antibodies as the capture probes for targets and the secondary antibodies functionalized goat anti-mouse immunoglobulin G labeled fluorescein isothiocyanate as the fluorescence signal probes. Through the competitive reaction of ZEA in Coix seed samples and that covalently coupled on the surface of MBs with their specific antibodies, as well as fast magnetic separation and sensitive fluorescence detection, the developed MBPA strategy allowed low limit of detection (2.03 ng/mL) with broad dynamic range (2.03-440.67 ng/mL), as well as excellent accuracy with the average recovery rate of 96.39% and relative standard deviation (RSD) of 5.48% for ZEA. 36 samples could realize simultaneous analysis in one operation within less than 20 min only needing 50 µL of solution and 30 s of sampling, avoiding large consumption of time and organic solvents. Multiple centrifugation and cleanup steps were omitted because of magnetic separation, avoiding the loss of targets. Diverse capture and fluorescent probes can be randomly bound onto the surface of MBs, making the MBPA strategy a promising tool for on-site high-throughput monitoring of various trace hazard factors in food safety, and environmental monitoring.


Assuntos
Coix/química , Imunoensaio/métodos , Zearalenona/análise , Animais , Anticorpos Imobilizados/química , Anticorpos Imobilizados/imunologia , Coix/metabolismo , Grão Comestível/química , Grão Comestível/metabolismo , Concentração de Íons de Hidrogênio , Separação Imunomagnética , Limite de Detecção , Camundongos , Sementes/química , Sementes/metabolismo , Espectrometria de Fluorescência , Zearalenona/imunologia , Zearalenona/isolamento & purificação
8.
PLoS One ; 15(9): e0239479, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32966310

RESUMO

Mycotoxin management in agriculture is an essential challenge for maintaining the health of both animals and humans. Choosing the right adsorbent is still a question for many breeders and an important criterion for feed manufacturers. New adsorbents are still being sought. Graphene oxide is a promising material in the field of nanotechnology, which excels in its adsorption properties. Presented in vitro study investigates graphene oxide for the binding of mycotoxins from crushed wheat. The results show that graphene oxide has an adsorption capacity for aflatoxin 0.045 mg/g, zearalenone 0.53 mg/g and deoxynivalenol 1.69 mg/g at 37° C. In vitro simulation of crushed wheat digestion showed rapid adsorption during the gastric phase. Of the minerals, Mg, Cu and Zn were the most adsorbed. The applied dose of graphene oxide of 10 mg/g caused only a slight inhibition of the digestive enzymes α-amylase and trypsin compared to pepsin and gastric lipase. In vitro results indicated the suitability of graphene oxide in the adsorption of the aflatoxin, zearalenone and deoxynivalenol.


Assuntos
Grafite/química , Micotoxinas/isolamento & purificação , Adsorção , Aflatoxina B1/isolamento & purificação , Aflatoxina B1/toxicidade , Ração Animal/análise , Ração Animal/toxicidade , Animais , Digestão , Contaminação de Alimentos/análise , Contaminação de Alimentos/prevenção & controle , Absorção Gastrointestinal , Humanos , Técnicas In Vitro , Micotoxinas/toxicidade , Nanoestruturas/química , Tricotecenos/isolamento & purificação , Tricotecenos/toxicidade , Triticum/química , Triticum/toxicidade , Zearalenona/isolamento & purificação , Zearalenona/toxicidade
9.
Anal Biochem ; 610: 113928, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-32860746

RESUMO

This study describes a smart analysis platform capable of quantitative measurements using a multiplex lateral flow strip. Using the multi-mycotoxin strip, five fungal toxins were simultaneously and quantitatively detected in naturally contaminated wheat. First, a matrix-based standard curve was established for the detection of aflatoxin B1 (AFB1), fumonisin B1 (FB1), T-2, deoxynivalenol (DON), and zearalenone (ZEN). Established on an open android system, the platform is able to read 6 lines on the strip simultaneously. The platform is equipped with a Quick Response code scanning model, which reads the established standard curves, and then rapidly quantify mycotoxins in naturally contaminated wheat. All the data and sample information are stored on a central server through the platform which is linked to the cloud. The limits of detection (LOD) for AFB1, FB1, T-2, DON, and ZEN in wheat were 4, 20, 10, 200, and 40 µg/kg and the visual cut off values was 20, 1000, 200, 4000, and 400 µg/kg, separately. To validate the platform and the multi-mycotoxin detection method, 10 wheat samples were analyzed and the results were in a good agreement with those obtained by LC-MS/MS. The platform will be a powerful tool for crop monitoring services.


Assuntos
Contaminação de Alimentos/análise , Imunoensaio/métodos , Micotoxinas/análise , Triticum/metabolismo , Aflatoxina B1/análise , Aflatoxina B1/imunologia , Aflatoxina B1/isolamento & purificação , Anticorpos/química , Anticorpos/imunologia , Fumonisinas/análise , Fumonisinas/imunologia , Fumonisinas/isolamento & purificação , Ouro/química , Limite de Detecção , Nanopartículas Metálicas/química , Micotoxinas/imunologia , Micotoxinas/isolamento & purificação , Sistemas Automatizados de Assistência Junto ao Leito , Triticum/química , Zearalenona/análise , Zearalenona/imunologia , Zearalenona/isolamento & purificação
10.
Anal Bioanal Chem ; 412(17): 4045-4055, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32356099

RESUMO

Surface-imprinted polymers supported by hydroxyapatite (HAP@MIPs) were prepared using coumarin-3-carboxylic acid and naringenin as dummy template molecules of zearalenone (ZEA). HAP@MIPs were characterized by Fourier-transform infrared spectroscopy, scanning electron microscopy, particle size distribution analysis, energy-dispersive X-ray spectroscopy, and X-ray diffraction. The adsorption performance was studied. The results showed that it could reach the adsorption equilibrium within 6 min. The adsorption amount could reach 6.77 µg mg-1, while the concentration was 20 µg mL-1. The self-made solid-phase extraction (SPE) columns were prepared with HAP@MIPs as sorbents for the separation and purification of ZEA in cereal samples. The method was established by high-performance liquid chromatography (HPLC). The recoveries were in the range of 70.09-101.88%; the relative standard deviation was 2.06-8.47%. Finally, millet, coix lachryma, and corn were placed under extreme conditions to produce ZEA. The method was used to extract and analyze ZEA in the above samples. The results showed that self-made SPE columns with HPLC could be used for the separation and enrichment of ZEA in real samples. Graphical abstract.


Assuntos
Durapatita/química , Grão Comestível/química , Impressão Molecular/métodos , Polímeros/química , Zearalenona/isolamento & purificação , Adsorção , Cromatografia Líquida de Alta Pressão/métodos , Coix/química , Milhetes/química , Extração em Fase Sólida/métodos , Zea mays/química
11.
Molecules ; 25(10)2020 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-32456190

RESUMO

The co-occurrence of moniliformin (MON), fumonisins (FBs), and deoxynivalenol (DON) was evaluated in maize, durum, and common wheat grown in different experimental fields located in several Italian regions. MON was quantified using a LC-MS/MS method adding lanthanum ions in the mobile phase. In maize, MON contamination was widespread and considerable; the toxin was detected in almost all the samples (95.1%) and exceeded 500 and 1000 µg kg-1 in 42.0% and in 18.5% of samples, respectively. Significant positive correlation was found between MON and FB contamination levels. When there were not droughty climate conditions, a positive significant correlation was found between growing degree days (GDD) and MON values. In wheat, MON contamination was not widespread like in maize and it was lower in common wheat than in durum wheat. In durum wheat, MON was detected in 45.0% of the samples with only 6 samples (7.5%) exceeding 500 µg kg-1, while in common wheat the toxin was detected above the LOD in 18.7% of samples exceeding 100 µg kg-1 in only two samples (2.5%). No correlation was found with DON contamination. Climate conditions influenced both MON and DON occurrence.


Assuntos
Ciclobutanos/química , Contaminação de Alimentos , Micotoxinas/química , Toxina T-2/química , Ciclobutanos/isolamento & purificação , Grão Comestível/química , Fusarium/química , Fusarium/patogenicidade , Humanos , Itália , Micotoxinas/isolamento & purificação , Toxina T-2/isolamento & purificação , Espectrometria de Massas em Tandem , Triticum/química , Triticum/crescimento & desenvolvimento , Triticum/microbiologia , Zea mays/química , Zea mays/crescimento & desenvolvimento , Zea mays/microbiologia , Zearalenona/química , Zearalenona/isolamento & purificação
12.
BMC Microbiol ; 20(1): 48, 2020 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-32126973

RESUMO

BACKGROUND: The root-knot nematode Meloidogyne graminicola has become a serious threat to rice production as a result of the cultivation changes from transplanting to direct seeding. The nematicidal activity of Aspergillus welwitschiae have been investigated in vitro, and the disease control efficacy of the active compound has been evaluated under greenhouse and field conditions. RESULTS: The active compound αß-dehydrocurvularin (αß-DC), isolated by nematicidal assay-directed fractionation, showed significant nematicidal activity against M. graminicola, with a median lethal concentration (LC50) value of 122.2 µg mL- 1. αß-DC effectively decreased the attraction of rice roots to nematodes and the infection of nematodes and also suppressed the development of nematodes under greenhouse conditions. Moreover, αß-DC efficiently reduced the root gall index under field conditions. CONCLUSIONS: To our knowledge, this is the first report to describe the nematicidal activity of αß-DC against M. graminicola. The results obtained under greenhouse and field conditions provide a basis for developing commercial formulations from αß-DC to control M. graminicola in the future.


Assuntos
Antiparasitários/farmacologia , Aspergillus/química , Oryza/crescimento & desenvolvimento , Tylenchoidea/efeitos dos fármacos , Zearalenona/análogos & derivados , Animais , Antiparasitários/isolamento & purificação , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cromatografia , Feminino , Efeito Estufa , Estrutura Molecular , Oryza/parasitologia , Doenças das Plantas/prevenção & controle , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/parasitologia , Tylenchoidea/crescimento & desenvolvimento , Zearalenona/química , Zearalenona/isolamento & purificação , Zearalenona/farmacologia
13.
Talanta ; 209: 120555, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31892075

RESUMO

A novel magnetic surface molecular imprinted polymers with 2, 4, 6-trisacrylamido-3, 5-triazine (TAT) as a functional monomer was successfully synthesized and used for the enrichment and determination of zearalenone. The molecular imprinting is reported herein at first time for application of zearalenone in wheat. The magnetic imprinted materials possessed excellent magnetism and uniform appearance, which were characterized by fourier transform infared spectroscopy and transmission electron microscope. The results proved the magnetic molecular imprinted polymers was successfully prepared. The magnetic molecular imprinted polymers exhibited satisfactory sensitivity, stability and potential reusability. The binding affinity was investigated by selectivity experiment, which possessed high selectivity. To obtain the optimal application conditions, the amount of adsorption, extraction time, elution solvent and time were optimized. The limited detection of zearalenone was 0.55 ng g-1 and the recoveries of zearalenone were 92.1-96.0%. The relative standard deviation was lower than 5.4%. This indicated that a simple, efficient and low-cost method was established and successfully applied in spiked wheat sample.


Assuntos
Imãs/química , Impressão Molecular/métodos , Polímeros/química , Triticum/química , Zearalenona/análise , Acrilamidas/química , Adsorção , Cromatografia Líquida de Alta Pressão/métodos , Triazinas/química , Zearalenona/isolamento & purificação
14.
Environ Sci Pollut Res Int ; 27(4): 4284-4293, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31832949

RESUMO

A series of modified montmorillonites treated by acid and hexadecyltrimethylammonium bromide (HTAB) were prepared and characterized, and their adsorption performances for three mycotoxins (aflatoxin B1, zearalenone, and deoxynivalenol) were evaluated at pH 2.8 and 8.0, respectively. The results indicate that the layers of raw montmorillonite are exfoliated after acid treatment and more active sites for adsorption of weak polar mycotoxins are exposed. While the intercalation of HTAB leads to an obvious increase of the interlamellar spacing and hydrophobic character of montmorillonite. The HTAB-AMMT-3 modified by acid and HTAB exhibits excellent adsorption capacity towards aflatoxin B1 (AFB1) and zearalenone (ZEA) whether in acidic or alkaline conditions compared with raw montmorillonite (MMT). However, all modified montmorillonites have low adsorption capacity for DON due to its poor planarity preventing it from entering into interfacial layer of montmorillonite.


Assuntos
Aflatoxina B1/isolamento & purificação , Bentonita/química , Cetrimônio/química , Zearalenona/isolamento & purificação , Adsorção
15.
Food Chem ; 307: 125546, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31639580

RESUMO

Zearalenone (ZEN) is one of the most widely distributed harmful mycotoxins produced by Fusarium species, especially deposited in corn oil. In this study, we systematically tracked the changes of ZEN in the refining of corn oil, and especially during neutralization process. An alkali neutralization process could remove certain amounts of ZEN that was much more than that of others refining steps. In a mimicking condition, ZEN contents decreased continuously and significantly with increasing neutralization temperature. However, when returned to neutral, recoverable ZEN decreased with increasing temperature, which confirmed more degradation of ZEN at high temperature. HPLC-Q/TOF MS and NMR evidence showed that non-reversible hydrolyzate followed decarboxylation was observed in a high-temperature alkali neutralization condition. The results may serve as the scientific basis for the elimination of zearalenone in refined vegetable oils, and provide clues to understanding the oil-safety aspects of elimination of zearalenone.


Assuntos
Óleo de Milho/química , Zea mays/química , Zearalenona/isolamento & purificação , Álcalis
16.
Toxins (Basel) ; 11(11)2019 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-31752226

RESUMO

Zearalenone (ZEN) is a non-steroidal estrogenic mycotoxin and constitutes a potential health threat to humans and livestock. This study aimed to explore the potential of albite modified by the cationic surfactant cetylpyridinium chloride (CPC) as ZEN adsorbent. The organoalbite (OA) was characterized by SEM analysis, XRD analysis, FTIR spectroscopy, thermal analysis, and BET gas sorption measurement. In vitro adsorption of ZEN by OA was carried out by simulating the pH conditions of the gastrointestinal tract. The characterization results showed that the surface of OA changed from hydrophilic to hydrophobic after modification. Adsorption kinetic studies showed that ZEN adsorption behavior of OA occurred by chemisorption. The equilibrium adsorption data fitted well with the Langmuir isotherm, indicating that the adsorption process of ZEN by OA was monolayer. The maximum adsorption capacity (qm) values of OA for ZEN were 10.580 and 9.287 mg/g at pH 7 and pH 3, respectively. In addition, OA had a low desorption rate (about 2%), and co-existing amino acids (i.e., Lys and Met), vitamins (i.e., VB1 and VE), and minerals (i.e., Fe2+ and Ca2+) did not affect the removal of ZEN. These results demonstrate that OA could be a promising mycotoxin adsorbent for removing the hydrophobic, weakly polar ZEN.


Assuntos
Cetilpiridínio/química , Estrogênios não Esteroides/química , Zearalenona/química , Adsorção , Estrogênios não Esteroides/isolamento & purificação , Cinética , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , Zearalenona/isolamento & purificação
17.
J Chromatogr A ; 1604: 460475, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31466701

RESUMO

Enrichment, separation and purification are very important to accurately analyze mycotoxins in complicated samples. In the work, we developed a new enrichment, purification and high-performance liquid chromatography combined with fluorescence detector (HPLC-FLD) for aflatoxins B1 (AFB1), ochratoxin A (OTA) and Zearalenone (ZEN) assay using the macroporous magnetic 3D photonic crystal microspheres (3DPCMs). The conditions of enrichment and purification for mycotoxins have been optimized, which are as follows: pore size of 3DPCMs at 280 nm, 1:1 methanol:acetonitrile (v/v) as eluent, antibody concentrations at 60 µg/mL,60 µg/mL and 120 µg/mL for OTA, AFB1 and ZEN, respectively. The recovery rates in the rice, wheat and corn samples range from 70.01% to 100.12% and the relative standard deviation (RSD) range from 0.45% to 7.09%. The recovery rates used 3DPCMs are almost tenfold higher than that used non-macroporous PCMs in the same conditions. The developed method is simple, rapid (time including enrichment, purification and detection <2 h) and only requires small volume reagents (≤200 µL).


Assuntos
Cromatografia Líquida de Alta Pressão/instrumentação , Cromatografia Líquida de Alta Pressão/métodos , Microesferas , Micotoxinas/análise , Fótons , Aflatoxina B1/análise , Aflatoxina B1/isolamento & purificação , Anticorpos/química , Cristalização , Fluorescência , Proteínas Imobilizadas/química , Micotoxinas/isolamento & purificação , Ocratoxinas/análise , Ocratoxinas/isolamento & purificação , Porosidade , Propriedades de Superfície , Zearalenona/análise , Zearalenona/isolamento & purificação
18.
J Chromatogr A ; 1602: 11-18, 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31160093

RESUMO

Surface molecularly imprinted polymers (MIL-101@MIPs) were prepared using MIL-101 as supporting core, imprinted polymers as selective shell synthesized with coumarin-3-carboxylic acid as dummy template of Zearalenone (ZEN), methacrylic acid as functional monomer, and ethylene glycol dimethacrylate hydroxyethyl methacrylate as cross-linker. The polymers were characterized by scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, and particle-size distribution analyses. MIL-101@MIPs were used as the sorbent to compose the self-made cartridge. The cartridge was used to purify and enrich ZEN from real samples. Under optimized SPE conditions, a self-made cartridge can be reused for at least seven cycles. Elution was monitored with a high-performance liquid chromatography-fluorescence detection system. The linearity of the method ranged within 6.25-250 ng kg-1. The limits of detection ranged within 2.09 - 4.16 ng kg-1, and the limits of quantification ranged within 6.25 -12.50 ng kg-1, respectively. The matrix effects of four real samples were discussed. The spiking recoveries of ZEN ranged within 81.70%-90.10% with relative standard deviations lower than 5.56%. The performance of the self-made cartridge and immunoaffinity column was compared by chromatography.


Assuntos
Grão Comestível/química , Polímeros/síntese química , Extração em Fase Sólida/métodos , Zearalenona/isolamento & purificação , Adsorção , Cromatografia Líquida de Alta Pressão , Cumarínicos/química , Limite de Detecção , Estruturas Metalorgânicas/química , Metacrilatos/química , Impressão Molecular , Oryza/química , Polímeros/química , Triticum/química , Zea mays/química , Zearalenona/análise
19.
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
20.
Biosens Bioelectron ; 130: 322-329, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30797178

RESUMO

In this study, a facile electrochemical sensing platform based on thin-layer MoS2 and thionin (MoS2-Thi) composites was constructed for the sensitive and rapid detection of zearalenone (ZEA) in human biofluids. MoS2-Thi composites with a thin-layer MoS2 structure and large specific surface area were synthesized via a simple ultrasound exfoliation method. To further enhance the performance of the platform but without increasing the complexity of the fabrication process, ZEA antibodies were modified with Pt nanoparticles (Pt NPs) using an environmentally friendly method, where they had a much wider linear range and four times higher sensitivity compared with the original ZEA monoclonal antibody (ZEA-MAb). Under the optimal conditions, the electrochemical responses of the MoS2-Thi composite-based immunosensor were linear (R2 = 0.9915) when the ZEA concentrations ranged from 0.01 to 50 ng mL-1. The proposed immunosensor could detect ZEA at concentrations as low as 0.005 ng mL-1 with excellent selectivity. The immunosensor exhibited acceptable stability with high reproducibility and accuracy, and it was applied successfully for determining ZEA in human plasma and urine samples. Our findings indicated that the proposed MoS2-Thi composite-based electrochemical sensing platform provides a new approach for the rapid and sensitive bioanalysis of ZEA, and it may also be extended to other mycotoxins for multiplex detection.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Imunoensaio , Zearalenona/isolamento & purificação , Anticorpos Imobilizados/química , Dissulfetos/química , Ouro/química , Grafite/química , Humanos , Limite de Detecção , Nanopartículas Metálicas/química , Molibdênio/química , Zearalenona/química
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