Zearalenone Dotaz Zobrazit nápovědu
Two Bacillus strains; Bacillus subtilis 168 and Bacillus natto CICC 24640 separately adsorbed and degraded zearalenone in liquid media, in vitro. Viable, autoclaved (121°C, 20 min) and acid-treated cells of both strains separately bound more than 55% of zearalenone (ZEN, 20 μg/L) after 30 min and 1-h incubation at 37°C under aerobic conditions, and the amount of ZEN adsorbed was dependent on initial cell volume. In addition, ZEN was degraded by the culture extract of both strains. Degradation by B. subtilis 168 and B. natto CICC 24640 culture extract after 24-h aerobic incubation at 30°C was 81% and 100%, respectively. B. natto CICC 24640 culture extract comprehensively degraded ZEN and, for both strains, no oestrogenic ZEN analogues were present. ZEN degradation was accompanied by carbondioxide emission indicating a decarboxylation reaction. ZEN degradation by the salient B. natto CICC 24640 culture extract varied with initial ZEN concentration, incubation time, temperature and pH. Degradation was enhanced by Mn(2+), Zn(2+), Ca(2+) and Mg(2+) but impeded by Hg(2+), Cu(2+), Pb(2+), ethylenediaminetetraacetic acid and 1,10-phenanthroline. The degradation reaction is associated with a metalloproteinase of molar mass in the range 31-43 kDa. Overall, the two generally recognised as safe Bacillus strains can, potentially, be utilised for detoxification of zearalenone in food.
Zearalenone (ZEN) is a toxic secondary metabolite of Fusarium sp. commonly found in wheat, corn, and other crops. In addition to economic losses, ZEN can seriously endanger the health of both humans and livestock, thus presenting an urgent need for ZEN-detoxifying enzymes that function in the extreme heat or pH conditions of industrial fermenters. Here, we identify and characterize the activity of the ZEN-degrading enzyme from Exophiala spinifera, ZHD_LD, which shares 60.15% amino acid identity and a conserved catalytic triad with the well-characterized ZEN-detoxifying protein ZHD101 from Clonostachys rosea. Biochemical activity and stability assays indicated that purified recombinant ZHD_LD exhibited high activity against ZEN with optimal reaction conditions of 50 °C and pH 7.0-10.0. Structural modeling of the ZHD_LD active site and comparison with ZHD101 revealed its likely mechanism of ZEN degradation. This research provides an industrially valuable candidate enzyme for ZEN detoxification in food and livestock feed.
- MeSH
- Fusarium * metabolismus MeSH
- hydrolasy metabolismus MeSH
- lidé MeSH
- pšenice metabolismus MeSH
- zearalenon * chemie metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
We tested the effect of two different concentrations (150μg/l and 0.15μg/l) of mycotoxin zearalenone (ZEA) on the reproductive parameters and expression of testicular genes in male mice. In adult males, no reduction of body or reproductive organ weight was observed, and the seminiferous tubules were morphologically normal with ongoing spermatogenesis. However, we found decreased sperm concentration, increase of morphologically abnormal spermatozoa and increased binding of apoptotic marker annexin V. This study was also focused on the evaluation of gene expression profiles of 28 genes playing important roles during the processes occurring in the testicular tissue. We detected changes in the expression of genes important for proper spermatogenesis. Surprisingly, we observed a stronger effect after exposure to the lower dose of ZEA.
- MeSH
- apoptóza účinky léků MeSH
- estrogeny nesteroidní toxicita MeSH
- exprese genu účinky léků MeSH
- myši MeSH
- spermatogeneze účinky léků MeSH
- spermie účinky léků patologie MeSH
- testis účinky léků metabolismus MeSH
- zearalenon toxicita MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Due to increasing food safety standards, the analysis of mycotoxins has become essential in the food industry. In this work, we have developed a competitive upconversion-linked immunosorbent assay (ULISA) for the analysis of zearalenone (ZEA), one of the most frequently encountered mycotoxins in food worldwide. Instead of a toxin-conjugate conventionally used in competitive immunoassays, we designed a ZEA mimicking peptide extended by a biotin-linker and confirmed its excellent suitability to mimic ZEA by nuclear magnetic resonance (NMR) and surface plasmon resonance (SPR) analysis. Upconversion nanoparticles (UCNP, type NaYF4:Yb,Tm) served as background-free optical label for the detection of the peptide mimetic in the competitive ULISA. Streptavidin-conjugated UCNPs were prepared by click reaction using an alkyne-PEG-neridronate linker. The UCNP conjugate clearly outperformed conventional labels such as enzymes or fluorescent dyes. With a limit of detection of 20 pg mL-1 (63 pM), the competitive ULISA is well applicable to the detection of ZEA at the levels set by the European legislation. Moreover, the ULISA is specific for ZEA and its metabolites (α- and β-zearalenol) without significant cross-reactivity with other related mycotoxins. We detected ZEA in spiked and naturally contaminated maize samples using liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) as a reference method to demonstrate food analysis in real samples.
The mycotoxin zearalenone (ZEA) in food and feed seriously harms human and animal health. How to reduce its toxicity is an important direction of current research on food safety. This study aim to assess the effects of procyanidins (PC) on cell apoptosis caused by ZEA and to clarify the role of Nrf2 in the process. Swine testicle (ST) cells were treated with ZEA (57.5 μmol/L) and/or PC (10 mg/L) for 24 h. Cell viability was detected by CCK-8 assay. Cell apoptosis and the level of ROS were detected by flow cytometry. The expression levels of mRNA and protein was detected by qRT-PCR and western blotting. Our results showed that ZEA reduced the antioxidant capacity of the ST cells, induced the cell apoptosis and inhibited the gene and protein expression of Nrf2 and its downstream genes (ho-1,nqo1), while PC improved the cell antioxidant capacity, reduced the degree of ZEA-induced cell apoptosis and promoted the gene and protein expression of Nrf2 and its downstream genes. However, when the Nrf2 small molecule inhibitor ML385 was added, the ability of PC to inhibit ZEA-induced cell apoptosis and promote the expression of Nrf2 and its downstream genes were decreased. Our results demonstrated that ZEA induced oxidative stress and apoptosis of ST cells, which were alleviated by PC intervention via activating Nrf2 signaling pathway. This finding of this study provided a molecular basis for the clinical application of PC to prevent ZEN-caused reproductive toxicity.
- MeSH
- antioxidancia metabolismus farmakologie MeSH
- apoptóza MeSH
- faktor 2 související s NF-E2 genetika metabolismus MeSH
- oxidační stres MeSH
- prasata MeSH
- proantokyanidiny * farmakologie MeSH
- reaktivní formy kyslíku metabolismus MeSH
- signální transdukce MeSH
- testis metabolismus MeSH
- zearalenon * metabolismus MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
A dietary exposure assessment to sum of deoxynivalenol (DON) forms, sum of T-2/HT-2 toxins (T2/HT2) and zearalenone (ZEA) was conducted for Czech children 4-6 years and Czech men and women 18-59 years. Retail foods (25 different commodities, n = 336) were assessed by LC-MS/MS methods. The 95th percentile chronic exposure to sum of DON forms was determined in children from 648 to 1030 ng/kg bw/day (LB/lower bound/and UB/upper bound/), in men from 362 to 923 ng/kg bw/day and in women from 272 to 490 ng/kg bw/day. The 95th percentile chronic exposure to sum T2/HT2 was determined in children from 6.5 to 31 ng/kg bw/day, in men from 1.9 to 11.2 ng/kg bw/day and in women from 2.5 to 11.5 ng/kg bw/day. The 95th percentile chronic exposure to ZEA was determined in children from 11.9 to 24.9 ng/kg bw/day, in men from 5.9 to 27.5 ng/kg bw/day and in women from 4.8 to 12.6 ng/kg bw/day. The risk linked with the mean and the 95th percentile chronic exposure (LB scenario) to the sum of DON forms, sum of T2/HT2 and ZEA is considered to be out of health concern for the selected population groups.
- MeSH
- dietární expozice * MeSH
- dítě MeSH
- dospělí MeSH
- jedlá semena chemie MeSH
- kontaminace potravin analýza MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- mykotoxiny analýza MeSH
- pivo analýza MeSH
- předškolní dítě MeSH
- T-2 toxin analogy a deriváty toxicita MeSH
- trichotheceny toxicita MeSH
- zearalenon toxicita MeSH
- Check Tag
- dítě MeSH
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- předškolní dítě MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Sample preparation prior to chromatographic separation plays an important role in the analytical process. To avoid time-consuming and manual handling sample-prep, automated on-line techniques such as on-line SPE-HPLC are therefore preferred. In this study, two different on-line extraction approaches for mycotoxin/endocrine disruptor zearalenone (ZEA) determination using either molecularly imprinted polymer (MIP) with selective cavities and binding sites for extraction or a reversed-phase sorbent C18 providing non-selective interactions have been developed, validated, and compared. The validation characteristics were compared and the two methods were evaluated as being almost equal in terms of linearity, repeatability, precision, and recovery. Recoveries were in the range of 99.0-100.1% and limits of detection were found the same for both methods (1.5 μg L-1). Method precision calculated for spiked beer samples was better for C18 sorbent (2.5 vs. 5.4% RSD). No significant differences in the selectivity of either extraction method were observed. The possible reasons and further details associated with this finding are discussed. Finally, both validated methods were applied for the determination of ZEA contamination in beer samples. Due to ZEA's native fluorescence, chromatographic separation with fluorimetric detection (λex = 270 nm and λem, = 458 nm) was selected. Graphical abstract Determination of zearalenone in beer using an on-line extraction chromatography system.
- MeSH
- analýza potravin metody MeSH
- chromatografie s reverzní fází metody MeSH
- endokrinní disruptory analýza MeSH
- estrogeny nesteroidní analýza MeSH
- extrakce na pevné fázi metody MeSH
- limita detekce MeSH
- molekulový imprinting metody MeSH
- mykotoxiny analýza MeSH
- pivo analýza MeSH
- vysokoúčinná kapalinová chromatografie metody MeSH
- zearalenon analýza MeSH
- Publikační typ
- časopisecké články MeSH
- validační studie MeSH
