Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 3.588
Filtrar
1.
Spectrochim Acta A Mol Biomol Spectrosc ; 264: 120264, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34375837

RESUMO

An entropy driven catalytic reaction powered DNA motor was proposed for simultaneous detection of ochratoxin A (OTA) and chloramphenicol (CAP) in food. The dumbbell hairpin structure was formed by the two aptamers of OTA and CAP. The dumbbell hairpin can be opened by the interaction of OTA and CAP with their aptamers. The tails of the end of dumbbell hairpin sequence can induce the entropy driven catalytic reactions on the AuNPs, causing the sustained releasing of the fluorophore labeled DNA sequences. The recovery of fluorescent intensities can be used for quantitative detection of OTA and CAP. The limit of detection reached 2 pM for OTA and 6 pM for CAP respectively, which was great improved by entropy driven amplification of the self-powdered DNA motor. This strategy is simple and sensitive and only needs one-step operation. It exhibits promising potentiality in food quality control and food security supervision.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Nanopartículas Metálicas , Cloranfenicol , DNA , Entropia , Ouro , Limite de Detecção , Ocratoxinas
2.
Food Chem ; 371: 131157, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34583180

RESUMO

Ochratoxin A (OTA) is a very important mycotoxin. However, there are few studies on the removal of OTA in wine because of the great influence on product quality and difficulty in practical application. A nano-MgO-modified diatomite ceramic membrane (MCM) with a high positive charge was prepared and applied to remove OTA in wine. The isotherm adsorption between the positively charged membrane and OTA was in accordance with the Langmuir model, with a maximum adsorption capacity of 806 ng/g at 25 °C. All of the changes in adsorption enthalpy (ΔH), adsorption free energy (ΔG) and adsorption entropy (ΔS) were negative, which indicated that the combination of nano-MgO MCM and OTA was a spontaneous exothermic and nonspecific physical adsorption process. The concentrations of OTA in adsorption-treated wines were lower than 2 µg/kg, and the removal rates exceeded 92%. After OTA removal, the composition of wines was preserved to some extent.


Assuntos
Ocratoxinas , Vinho , Adsorção , Cerâmica , Ocratoxinas/análise , Eletricidade Estática , Vinho/análise
3.
Chemosphere ; 287(Pt 1): 131994, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34478969

RESUMO

In this work, a CdSe@CdS quantum dots (QDs) based label-free electrochemiluminescence (ECL) aptasensor was developed for the specific and sensitive detection of ochratoxin A (OTA). Chitosan (CHI) could immobilize abundant QDs on the surface of an Au electrode as the luminescent nanomaterials. Glutaraldehyde was used as the crosslinking agent for coupling a large number of OTA aptamers. Thanks to the excellent stability, good biocompatibility, and strong ECL intensity of CdSe@CdS QDs, as well as the quick reactions of the generated SO4•- in the electrolyte, strong ECL signals were measured. Because of the specific recognition of aptamer toward OTA, the reduced ECL signals caused by OTA in the samples were recorded for quantify the content of OTA. After optimizing a series of crucial conditions, the ECL aptasensor displayed superior sensitivity for OTA with a detection limit of 0.89 ng/mL and a wide linear concentration range of 1-100 ng/mL. The practicability and viability were verified through the rapid and facile analysis of OTA in real Lily and Rhubarb samples with recovery rates (n = 3) of 98.1-105.6% and 97.3-101.5%, respectively. The newly-developed QDs-based ECL aptasensor provided a new universal analytical tool for more mycotoxins in safety assessment of foods and feeds, environmental monitoring, and clinical diagnostics.


Assuntos
Técnicas Biossensoriais , Compostos de Cádmio , Pontos Quânticos , Compostos de Selênio , Técnicas Eletroquímicas , Medições Luminescentes , Ocratoxinas
4.
J Agric Food Chem ; 69(46): 13974-13989, 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34783556

RESUMO

Ochratoxins (OTs) with nephrotoxic, immunosuppressive, teratogenic, and carcinogenic properties are thermostable fungal subordinate metabolites. OTs contamination can occur before or after harvesting, during the processing, packing, distribution, and storage of food. Mold development and mycotoxin contamination can occur in any crop or cereal that has not been stored properly for long periods of time and is subjected to high levels of humidity and temperature. Ochratoxin A (OTA) presents a significant health threat to creatures and individuals. There is also a concern of how human interaction with OTA will also express the remains of OTA from feedstuffs into animal-derived items. Numerous approaches have been studied for the reduction of the OTA content in agronomic products. These methods can be classified into two major classes: inhibition of OTA adulteration and decontamination or detoxification of food. A description of the various mycotoxins, the organism responsible for the development of mycotoxins, and their adverse effects are given. In the current paper, the incidence of OTA in various fodder and food materials is discussed, which is accompanied by a brief overview of the OTA mode of synthesis, physicochemical properties, toxic effects of various types of ochratoxins, and OTA decontamination adaptation methods. To our knowledge, we are the first to report on the structure of many naturally accessible OTAs and OTA metabolism. Finally, this paper seeks to be insightful and draw attention to dangerous OTA, which is too frequently neglected and overlooked in farm duplication from the list of discrepancy studies.


Assuntos
Micotoxinas , Ocratoxinas , Ração Animal/análise , Animais , Grão Comestível/química , Contaminação de Alimentos/análise , Humanos , Micotoxinas/toxicidade , Ocratoxinas/análise
5.
Anal Chim Acta ; 1188: 339189, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34794565

RESUMO

Here, a plasmonic nanogap structure was fabricated with its specific surface enhanced Raman spectroscopy (SERS) effect to construct an aptasensor for the sensitive detection of ochratoxin A (OTA). Gold nanorod (AuNR) were synthesized first by seed-mediated method. Then, silver was reduced and grown on its surface. In the presence of glycine, Ag0 was preferred to grow at both ends of AuNR to form gold@silver nanodumbbell (Au@AgND). The thiolated OTA aptamer and its complementary sequence were modified on Au@AgND respectively using Ag-SH bond. Under the base complementary pairing principle, Au@AgND assembly formed with certain inter distances. The inter-nanogap structure generated more hot spots which enhanced the Raman signal of 4-hydroxybenzoic acid (4-MBA) immobilized on Au@AgND. When OTA was present, the aptamer preferentially combined to OTA and the Au@AgND assembly disintegrated. Thus, the SERS signal of 4-MBA decreased. Under the optimal conditions, the OTA concentrations were inversely proportional to SERS signal. The linear range was 0.01 ng/mL-50 ng/mL and the limit of detection (LOD) was 0.007 ng/mL. The method can be successfully applied to the detection of real sample (beer/peanut oil).


Assuntos
Aptâmeros de Nucleotídeos , Nanopartículas Metálicas , Ouro , Ocratoxinas , Prata , Análise Espectral Raman
6.
J Agric Food Chem ; 69(40): 12021-12029, 2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34606275

RESUMO

A specialized method for ochratoxin A (OTA) determination on fermented teas was developed and validated using ultraperformance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). Methodology results showed that recovery, relative standard deviation, accuracy, and precision were qualified. The limits of detection and quantification were 0.32 and 0.96 µg/kg, respectively. Two of 158 collected samples were screened for OTA contamination. Comprehensive risk assessment based on OTA contaminations of this study and other peer-reviewed publications was performed. The highest hazard quotient (HQ) value (8.86 × 10-2) and the highest 1/MoE value (8.61 × 10-5) in probabilistic assessment were equally below the recommended non-neoplastic and neoplastic thresholds, indicating no health risks. However, the HQ and 1/MoE values of the 95th percentiles in 20-39 and ≥50 years of age were close to thresholds of 1.0 and 1.0 × 10-4, respectively. Under the extreme case, there were only a few scenarios (e.g., 40-49 years of age) of HQ values below the non-neoplastic threshold, but the 1/MoE value of each group exceeded the neoplastic threshold. This is the first extensive risk assessment on OTA from fermented teas worldwide, but the sample size is still limited, and a large number of samples is encouraged in a future study for a more accurate assessment.


Assuntos
Exposição Dietética , Ocratoxinas , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Contaminação de Alimentos/análise , Ocratoxinas/análise , Medição de Risco , Espectrometria de Massas em Tandem
7.
Anal Chim Acta ; 1185: 339077, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34711314

RESUMO

Herein, a facile protocol of simple DNA adsorption on UV-initiated polymerization supports was proposed for effectively fabricating aptamer-based affinity monolithic column. Hydrophilic cationic monolith with an excellent mechanical stability was achieved within 7 min and then massive aptamers were directly bound by DNA charge-dependent adsorption. Strong cationic quaternary ammonium-based monomer was employed to provide effective and stable positive charge surface for aptamer immobilization in a wide range of pH. An ultra-high aptamer coverage density of 6813 pmol/µL was achieved to gain a highly specific online recognition performance. Limitations such as low aptamer capacity, tedious modification and time-consuming reactions in the traditional biological or covalent modification strategies were avoided. By using ochratoxin A (OTA) as the given analyte, the selective recognition and high recoveries were successfully achieved, and little cross-reactivity towards OTB analogue was only 0.5% even if the content of OTB got up to 125 folds of OTA. Applied to sample analysis, the satisfactory discriminations of trace OTA were obtained at 93.9 ± 1.9% - 96.5 ± 1.7%(n = 3)in beer, wheat and chicken liver samples. It might light a cost-effective access to efficiently preparing high-performance affinity monoliths towards the selective in-tube microextraction of OTA.


Assuntos
Compostos de Amônio , Aptâmeros de Nucleotídeos , Ocratoxinas , Adsorção , DNA
8.
J Food Sci ; 86(11): 4799-4810, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34642959

RESUMO

Under the Food Safety Modernization Act (FSMA) and preventive controls (PCs) regulations, food manufacturers must consider whether PCs are needed for potential hazards present in food. The mycotoxin ochratoxin A (OTA) is considered a chemical hazard under FSMA. It is produced by several fungal species and can be present in various agricultural commodities, including coffee. OTA presents a unique scenario in food safety, because it is known to be a potential risk; because heating may destroy it, but not completely; and because the hazard profile suggests it is not acutely toxic at the occurrence levels in coffee, although at high exposure levels, it is potentially nephrotoxic and carcinogenic in animal models. In the absence of US compliance levels, it is important for the risk assessor and risk manager to determine whether PCs are warranted. To address this complex situation in the coffee industry, we combined food safety and toxicology risk assessment principles to examine the available information on OTA hazard and risk in coffee. Exposure and health-based benchmarks for OTA in coffee, established by reviewing peer-reviewed literature, food recall databases, and authoritative reviews, resulted in large margins-of-exposure for both single and repeated exposure scenarios. Furthermore, no evidence was identified from historical data to suggest OTA is acutely toxic in humans from coffee consumption or other exposure sources. Therefore, findings from this assessment indicate that no PC is warranted for US coffee manufactures, based on the low severity and likelihood of risk according to margin-of-exposure estimates and historical data.


Assuntos
Café , Ocratoxinas , Animais , Contaminação de Alimentos/análise , Inocuidade dos Alimentos , Humanos , Ocratoxinas/análise , Ocratoxinas/toxicidade
9.
J Agric Food Chem ; 69(38): 11461-11469, 2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34542274

RESUMO

Our previous study showed that ochratoxin A (OTA), one of the most common mycotoxins in feed, could induce immunosuppression with long-time exposure but immunostimulation with short-time exposure. However, limited studies for the control of OTA-induced two-way immune toxicity were carried out. This study explored the effects of mannan oligosaccharide (MOS), a glucomannoprotein complex with immunoregulatory capability derived from the yeast cell wall, on OTA-induced immune toxicity and its underlying mechanisms. Surprisingly, the results showed that MOS significantly attenuated immunosuppression induced by long-time OTA treatment but did not provide protection against immunostimulation induced by short-time OTA treatment on porcine alveolar macrophages (PAMs), as demonstrated by the expressions of inflammatory cytokines and the capability of migration and phagocytosis. Further, MOS increased the OTA-inhibited autophagy level and the JNK phosphorylation level on PAMs with long-time OTA treatment. In addition, the inhibition of autophagy by 3-MA or the inhibition of JNK phosphorylation by SP600125 could partly block the protective effects of MOS on OTA-induced immunosuppression. Importantly, the inhibition of JNK phosphorylation down-regulated the MOS-promoted autophagy level. In conclusion, MOS could attenuate OTA-induced immunosuppression with short-time exposure on PAMs through activating JNK-mediated autophagy but had no significant effects on OTA-induced immunostimulation with short-time exposure. Our study provides new insights into the application of MOS as an immunoregulator against mycotoxin-induced immune toxicity.


Assuntos
Mananas , Ocratoxinas , Animais , Linhagem Celular , Imunização , Imunossupressão , Ocratoxinas/toxicidade , Oligossacarídeos , Suínos
10.
Arh Hig Rada Toksikol ; 72(3): 173-181, 2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34587668

RESUMO

Some mycotoxins such as beauvericin (BEA), ochratoxin A (OTA), and zearalenone (ZEA) can cross the blood brain barrier, which is why we tested the anti-inflammatory action of a pumpkin carotenoid extract (from the pulp) against these mycotoxins and their combinations (OTA+ZEA and OTA+ZEA+BEA) on a blood brain barrier model with co-cultured ECV304 and C6 cells using an untargeted metabolomic approach. The cells were added with mycotoxins at a concentration of 100 nmol/L per mycotoxin and pumpkin carotenoid extract at 500 nmol/L. For control we used only vehicle solvent (cell control) or vehicle solvent with pumpkin extract (extract control). After two hours of exposure, samples were analysed with HPLC-ESI-QTOF-MS. Metabolites were identified against the Metlin database. The proinflammatory arachidonic acid metabolite eoxin (14,15-LTE4) showed lower abundance in ZEA and BEA+OTA+ZEA-treated cultures that also received the pumpkin extract than in cultures that were not treated with the extract. Another marker of inflammation, prostaglandin D2-glycerol ester, was only found in cultures treated with OTA+ZEA and BEA+OTA+ZEA but not in the ones that were also treated with the pumpkin extract. Furthermore, the concentration of the pumpkin extract metabolite dihydromorelloflavone significantly decreased in the presence of mycotoxins. In conclusion, the pumpkin extract showed protective activity against cellular inflammation triggered by mycotoxins thanks to the properties pertinent to flavonoids contained in the pulp.


Assuntos
Cucurbita , Micotoxinas , Ocratoxinas , Barreira Hematoencefálica , Carotenoides/farmacologia , Micotoxinas/toxicidade , Extratos Vegetais/farmacologia
11.
Inorg Chem ; 60(18): 14457-14466, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34499476

RESUMO

A fascinating class of nicotinic-acid-ornamented tetrameric rare-earth (RE)-substituted phospho(III)tungstates [NH2(CH3)2]10Na4H8[RE2(NA)(HNA)(H2O)6(W2O4)(ß-H2P2IIIW13O49)(α-HPIIIW9O33)]2·22 H2O [RE = Nd3+ (1-Nd), Tb3+ (2-Tb), Dy3+ (3-Dy), Ho3+ (4-Ho), HNA = nicotinic acid] were isolated through a one-step reaction method of Na2WO4·2H2O, H3PO3, HNA, NH2(CH3)2·HCl, and RE(NO3)·6H2O. Of meticulous concern is that HPO32- was used as a template to construct tetrameric RE-substituted phospho(III)tungstates including mixed heteropolyoxotungstate building blocks. Their hybrid polyoxoanions are composed of two symmetrical [RE2(NA)(HNA)(H2O)6(W2O4)(ß-H2P2IIIW13O49)(α-HPW9O33)]11- units linked by RE-O-W bonds. The symmetrical unit consists of one peculiar heterometal nicotinic-acid-ornamented [RE2(NA)(HNA)(W2O4)]9+ cluster connecting a pentavacant Dawson-like [ß-H2P2W13O49]12- and a trivacant Keggin [α-HPW9O33]8- subunits. Furthermore, dimethyldioctadecylammonium chloride (DMDODA·Cl) was used to combine with 1-Nd in the CHCl3-H2O system through electrostatic interactions, leading to the 1-Nd@DMDODA composite material. The honeycomb-patterned film of the 1-Nd @DMDODA composite material was successfully constructed by using the breath figure method on a glassy carbon electrode, which can offer abundant binding sites to Au nanoparticles (nano-Au). Ulteriorly, Au-functionalized 1-Nd@DMDODA-modified electrode was utilized as an electrochemical sensor to detect ochratoxin A, showing a good detection limit of 1.19 pM.


Assuntos
Complexos de Coordenação/química , Metais Terras Raras/química , Nanopartículas/química , Niacina/química , Ocratoxinas/análise , Técnicas Eletroquímicas , Eletrodos
12.
Toxicon ; 200: 183-188, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34375657

RESUMO

Ochratoxin A (OTA) is a mycotoxin produced by the fungi Aspergillus and Penicillium. It occurs naturally in many products of plant origin and in animals because of the carry-over from feed to meat or milk. Ochratoxin A has nephrotoxic, carcinogenic, hepatotoxic, neurotoxic, and genotoxic properties. Data on ochratoxin concentrations in blood or serum from patients with different kidney disorders are available for several European countries, as well as for Africa and Asia. In this study, we determined OTA concentrations in serum samples from chronic renal failure patients receiving dialysis and from healthy controls, collected in central Poland. Ochratoxin A was analyzed after extraction and purification using immunoaffinity columns by liquid chromatography with fluorescence detection (limit of quantification: 0.1 ng/mL) in 88 patients and 16 healthy volunteers. The dialysis group consisted of 40 women and 48 men aged between 23 and 85 years. The mean OTA concentrations were 0.75 ng/mL (maximum 2.78 ng/mL) in dialysis patients and 0.70 ng/mL (maximum 1.44 ng/mL) in healthy controls. The mean concentrations in patients treated by dialysis were 0.76 and 0.74 ng/ml for women and men, respectively (maximum 2.53 ng/ml for women and 2.78 ng/ml for men). Statistical analysis using Student's t-test showed no statistically significant differences between the control group (non-dialysis patients) and all dialysis patients.


Assuntos
Falência Renal Crônica , Ocratoxinas , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Feminino , Humanos , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Polônia , Diálise Renal , Adulto Jovem
13.
Biosens Bioelectron ; 192: 113537, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34339903

RESUMO

Ochratoxin A (OTA) is one of the most toxic mycotoxins that exists in various agro-products and foods. Here, a non-label and enzyme-free fluorescence biosensor for highly specific detection of OTA has been developed by the combination of toehold-mediated strand displacement reaction (TMSD) and G-quadruplex dimer/ThT (G-dimer/ThT). The DNA duplex (aptamer-IP) is composed of the anti-OTA aptamer and a single stranded initiation probe (IP). In the presence of OTA, the attachment of target to aptamer leads to the liberation of the IP, which activates the cycle TMSD amplifications of two hairpin probes (H1 and H2) accompanied by the production of numerous H1-H2 assemblies. This double-stranded H1-H2 structure results in the proximity between the 5'-end overhang tail of H1 and the 3'-end stem of H2 to liberate the pre-blocked G-dimer sequence for lighting up ThT. In addition, the method displayed a stable fluorescence emission in the high-salt media. It was successfully applied to analyze OTA in real food samples. Hence, the constructed fluorescence biosensing platform might provide a new way for OTA and other toxin analysis detection.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Ocratoxinas , Corantes Fluorescentes , Limite de Detecção , Ocratoxinas/análise
14.
Food Microbiol ; 100: 103865, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34416965

RESUMO

The purpose of this study was to evaluate the inhibitory effect of allyl-isothiocyanate (AITC) and benzyl-isothiocyanate (BITC) on fungal growth and Ochratoxin A (OTA) production by Aspergillus ochraceus, A. carbonarius and A. niger. Here, we found that spore germination and fungal growth of the three fungi were significantly inhibited when the concentration of AITC and BITC was higher than 1.25 µg/mL. The inhibitory effect of AITC or BITC on A. carbonaceus and A. ochraceus was significantly stronger than that of A. niger. Scanning electron microscopy showed that the mycelia of all three fungi were changed by AITC and BITC. Compared with A. ochraceus and A. carbonarius, the damage to A. niger was lower. For OTA production, AITC and BITC could significantly down-regulated the expression of all five OTA biosynthesis genes in A. niger and A. carbonarius. In A. ochraceus, although several OTA biosynthesis genes were up-regulated, the key PKS gene was down-regulated by AITC and BITC. Twenty-five µg/mL of AITC or BITC could reduce the infection of the three fungi on grapes with inhibition rates of 28%-36% during 14 days and prolong the shelf life of grapes. In maize, the OTA production of the three fungi was significantly reduced by 25 µg/mL of AITC and BITC with the inhibition rates 68.04%-93.49% and 65.87%-75.45%, respectively. These results suggest that AITC and BITC can be used as natural fungicides to prevent A. niger, A. carbonarius and A. ochraceus from infecting grapes and maize and control OTA contamination.


Assuntos
Fungos/efeitos dos fármacos , Fungicidas Industriais/farmacologia , Isotiocianatos/farmacologia , Ocratoxinas/biossíntese , Vitis/microbiologia , Zea mays/microbiologia , Contaminação de Alimentos/análise , Fungos/crescimento & desenvolvimento , Fungos/metabolismo
15.
Biomolecules ; 11(7)2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34356666

RESUMO

(1) Background: ochratoxins are mycotoxins produced by filamentous fungi with important implications in the food manufacturing industry due to their toxicity. Decontamination by specific ochratoxin-degrading enzymes has become an interesting alternative for the treatment of contaminated food commodities. (2) Methods: using a structure-based approach based on homology modeling, blind molecular docking of substrates and characterization of low-frequency protein motions, we performed a proteome mining in filamentous fungi to characterize new enzymes with potential ochratoxinase activity. (3) Results: the proteome mining results demonstrated the ubiquitous presence of fungal binuclear zinc-dependent amido-hydrolases with a high degree of structural homology to the already characterized ochratoxinase from Aspergillus niger. Ochratoxinase-like enzymes from ochratoxin-producing fungi showed more favorable substrate-binding pockets to accommodate ochratoxins A and B. (4) Conclusions: filamentous fungi are an interesting and rich source of hydrolases potentially capable of degrading ochratoxins, and could be used for the detoxification of diverse food commodities.


Assuntos
Amidoidrolases/química , Amidoidrolases/metabolismo , Proteínas Fúngicas/metabolismo , Fungos/enzimologia , Ocratoxinas/metabolismo , Sítios de Ligação , Domínio Catalítico , Proteínas Fúngicas/química , Simulação de Dinâmica Molecular , Domínios Proteicos , Proteoma/metabolismo
16.
Chem Biol Interact ; 347: 109614, 2021 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-34364835

RESUMO

Ochratoxin A (OTA), an important fungal metabolite in foods and feeds has been shown to induce oxidative stress and cellular injuries to human and animal subjects. This study was designed to investigate the mode of action of a biological modifier Trichosporon mycotoxinivorans (TM), against OTA-mediated oxidative stress and tissue toxicity on broiler chickens. The birds were offered diets supplemented with OTA (0.15 and 0.3 mg/kg feed) and/or TM (0.5, 1.0 g/kg) for 42 days of age, and blood and tissue samples were collected to examine the oxidative stress, biochemical and histopathological parameters. Dietary OTA at all the tested levels induced the hepatic and renal tissue injury as indicated by significant decreased total antioxidant capacity in these organs along with significant decreased (p ≤ 0.05) serum concentrations of total proteins and albumin. The serum concentrations of alanine aminotransferase (ALT) and urea were significantly increased, and these observations were further supported by degenerative changes and increased relative weights of liver and kidneys. The dietary supplementation of TM at both tested levels relieved the detrimental impact of 0.15 and 0.3 mg OTA/kg on the studied parameters. The results of the study demonstrated that dietary TM significantly protects broiler chickens by reducing OTA-induced oxidative damage and tissue injury.


Assuntos
Basidiomycota/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/dietoterapia , Suplementos Nutricionais/microbiologia , Nefropatias/dietoterapia , Micotoxinas/toxicidade , Ocratoxinas/toxicidade , Animais , Aspergillus ochraceus , Galinhas , Rim/efeitos dos fármacos , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Micotoxinas/metabolismo , Ocratoxinas/metabolismo , Tamanho do Órgão/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos
17.
J Agric Food Chem ; 69(30): 8471-8481, 2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34304561

RESUMO

Botryosphaeria dothidea is a pathogenic fungus that can cause apple ring rot, a destructive apple disease in China. There have been reports on its molecular pathogenesis, but the pathogenic substances still remain unknown. In the present study, instrument analysis including UPLC-high-resolution mass spectrometry (HRMS) and nuclear magnetic resonance showed that B. dothidea fermentation broth contained (R)-(-)-mellein, a well-known fungal enantiomer of mellein. For further confirmation, a UPLC-MS/MS method for the determination of mellein was developed and validated. By this method, mellein was found to also exist in B. dothidea-infected apple fruits and branches with concentration ranges of 0.14-0.94 and 5.88-80.29 mg/kg, respectively. The concentration in fruits reached a peak at 48 h after pathogen inoculation, while a sustained concentration increase was achieved within 11 days for branches. Simultaneously, it was evident that there was a relation between disease spot expansion and mellein production kinetics in apple tissue. Phytotoxic bioassay showed that mellein could cause discoloration and death of apple leaves and browning in stems. Therefore, we confirmed that mellein was one of the pathogenic substances of B. dothidea. The present study provided additional data for the research on the pathogenesis of this pathogen.


Assuntos
Bioensaio , Espectrometria de Massas em Tandem , Ascomicetos , China , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Ocratoxinas
18.
ACS Appl Mater Interfaces ; 13(30): 35997-36010, 2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34288662

RESUMO

Two types of organic-inorganic hybrid structure-related lanthanide (Ln)-included selenotungstates (Ln-SeTs) [H2N(CH3)2]11Na7[Ce4(H2PTCA)2(H2O)12(HICA)]2[SeW4O17]2[W2O5]4[SeW9O33]4·64H2O (1, H3PTCA = 1,2,3-propanetricarboxylic acid, H2ICA = itaconic acid) and [H2N(CH3)2]6Na4[Ln4SeW8(H2O)14(H2PTCA)2O28] [SeW9O33]2·31H2O [Ln = Pr3+ (2), Nd3+ (3)] were obtained by Ln nature control. The primary frameworks of 1-3 are composed of trivacant Keggin-type [B-α-SeW9O33]8- and [SeW4Om]n- [Ln = Ce3+ (1), m = 17, n = 6; Ln = Pr3+ (2), Nd3+ (3), m = 18, n = 8] fragments bridged by organic ligands and Ln clusters. Intriguingly, Ln nature results in the degradation of hexameric 1 to trimeric 2-3. Besides, 1@DMDSA and 3@DMDSA composites (DMDSA·Cl = dimethyl distearylammonium chloride) were prepared through the cation exchange method, which were then reorganized to form two-dimensional (2D) honeycomb thin films by the breath figure method. Using these honeycomb thin films as electrode materials, the aptasensors were further established by utilizing methylene blue as an indicator and cDNA and Au nanoparticles as signal amplifiers to enhance the response signal so as to realize the purpose of ochratoxin A (OTA) detection. This work provides a new platform for detecting OTA and explores the application potential of POM-based composites in biological and clinical analyses.


Assuntos
Ocratoxinas/sangue , Compostos de Selênio/química , Compostos de Tungstênio/química , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Ouro/química , Humanos , Limite de Detecção , Nanopartículas Metálicas/química , Azul de Metileno/química , Neodímio/química , Ocratoxinas/química , Praseodímio/química , Reprodutibilidade dos Testes
19.
Food Chem ; 365: 130409, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34256225

RESUMO

A new, green, and cost-effective magnetic solid-phase extraction of aflatoxins and ochratoxins from edible vegetable oils samples was developed using polydopamine-coated magnetic multi-walled carbon nanotubes (PDA@Fe3O4-MWCNTs) as the absorbent. PDA@Fe3O4-MWCNTs nanomaterials were prepared by chemical co-precipitation and in situ oxidation and self-polymerization of dopamine and was characterized. Factors affecting MSPE and the adsorption behavior of the adsorbent to mycotoxins were studied, and the optimal extraction conditions of MSPE and the complexity of the adsorption process were determined. Based on this, the magnetic solid-phase extraction-high-performance liquid chromatography-fluorescence detection method (MSPE-HPLC-FLD) was established for determining six mycotoxins [aflatoxin B1 (AFB1), AFB2, AFG1, and AFG2, and ochratoxin A (OTA) and OTB)] in vegetable oils. The recovery was 70.15%~89.25%, and RSD was ≤6.4%. PDA@Fe3O4-MWCNTs showed a high affinity toward aflatoxins and ochratoxins, allowing selective extraction and quantification of aflatoxins and ochratoxins from complex sample matrices.


Assuntos
Aflatoxinas , Nanotubos de Carbono , Ocratoxinas , Adsorção , Aflatoxinas/análise , Cromatografia Líquida de Alta Pressão , Dopamina , Contaminação de Alimentos/análise , Fenômenos Magnéticos , Ocratoxinas/análise , Óleos Vegetais , Verduras
20.
Res Vet Sci ; 139: 94-101, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34273745

RESUMO

Effects of Selenium-enriched probiotics (SP) on ochratoxin A-induced kidney injury, growth performance, antioxidant injury, selenoprotein and DNA methylation transferases (DNMTs) expression of piglets were investigated in the article. A total of 48 piglets were randomly divided into 4 groups and fed with basal diet (Con, 0.15 mg Se/kg and OTA at 0.00 mg/kg), basal diets added with OTA (OTA, 0.40 mg OTA/kg), SP and OTA (SP1, 0.15 mg Se/kg and 0.40 mg OTA/kg), SP and OTA (SP2, 0.30 mg Se/kg and 0.40 mg OTA/kg) respectively for 42 days. From each group, six piglets were randomly selected for blood collection on Days 0 and 42 and three piglets were selected for tissue collection on Day 42.The results showed that OTA at 0.40 mg /kg significantly decreased growth performance of pigs, induced the histopathological lesions of kidney and increased urea and creatine levels of serum, decreased GPx and SOD activities, and increased MDA levels. OTA decreased GPx1, GPx4 and SelS expressions, and increased TR1, DNMT 1, DNMT3a and SOCS3 expressions. Both SP1 and SP2 improved OTA-induced poor growth performance, kidney injury, poor antioxidant statues, GPx1, SelS, TR1, SOCS3, DNMT1 and DNMT3a expressions in kidney of pigs. The effects of SP2 on the above parameters changes were better than that of SP1. SP increased GPx and SOD activities and decreased MDA levels changes induced by OTA treatment. These results suggest that SP may serve as a better feed additive for piglets under mycotoxin contamination environments.


Assuntos
Rim/lesões , Ocratoxinas , Probióticos , Selênio , Ração Animal/análise , Animais , Metilação de DNA , Rim/metabolismo , Ocratoxinas/metabolismo , Selênio/metabolismo , Selênio/farmacologia , Suínos , Transferases/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...