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A clinical case in Belgium demonstrated that feeding a feed concentrate containing considerable levels of deoxynivalenol (DON, 1.13 mg/kg feed) induced severe liver failure in 2- to 3-month-old beef calves. Symptoms disappeared by replacing the highly contaminated corn and by stimulating ruminal development via roughage administration. A multi-mycotoxin contamination was demonstrated in feed samples collected at 15 different veal farms in Belgium. DON was most prevalent, contaminating 80% of the roughage samples (mixed straw and maize silage; average concentration in positives: 637 ± 621 µg/kg, max. 1818 µg/kg), and all feed concentrate samples (411 ± 156 µg/kg, max. 693 µg/kg). In order to evaluate the impact of roughage provision and its associated ruminal development on the gastro-intestinal absorption and biodegradation of DON and its acetylated derivatives (3- and 15-ADON) in calves, a toxicokinetic study was performed with two ruminating and two non-ruminating male calves. Animals received in succession a bolus of DON (120 µg/kg bodyweight (BW)), 15-ADON (50 µg/kg BW), and 3-ADON (25 µg/kg) by intravenous (IV) injection or per os (PO) in a cross-over design. The absolute oral bioavailability of DON was much higher in non-ruminating calves (50.7 ± 33.0%) compared to ruminating calves (4.1 ± 4.5%). Immediately following exposure, 3- and 15-ADON were hydrolysed to DON in ruminating calves. DON and its acetylated metabolites were mainly metabolized to DON-3-glucuronide, however, also small amounts of DON-15-glucuronide were detected in urine. DON degradation to deepoxy-DON (DOM-1) was only observed to a relevant extent in ruminating calves. Consequently, toxicity of DON in calves is closely related to roughage provision and the associated stage of ruminal development.

Over a 4-year period (2010-13), a survey aiming at determining the occurrence of Fusarium spp. and their relations to mycotoxins in mature grains took place in southern Belgium. The most prevalent species were F. graminearum, F. avenaceum, F. poae and F. culmorum, with large variations between years and locations. An even proportion of mating type found for F. avenaceum, F. culmorum, F. cerealis and F. tricinctum is usually a sign of ongoing sexual recombination. In contrast, an unbalanced proportion of mating type was found for F. poae and no MAT1-2 allele was present in the F. langsethiae population. Genetic chemotyping indicates a majority of deoxynivalenol (DON)-producing strains in F. culmorum (78%, all 3-ADON producers) and F. graminearum (95%, mostly 15-ADON producers), while all F. cerealis strains belong to the nivalenol (NIV) chemotype. Between 2011 and 2013, DON, NIV, enniatins (ENNs) and moniliformin (MON) were found in each field in various concentrations. By comparison, beauvericin (BEA) was scarcely detected and T-2 toxin, zearalenone and α- and β-zearalenols were never detected. Principal component analysis revealed correlations of DON with F. graminearum, ENNs and MON with F. avenaceum and NIV with F. culmorum, F. cerealis and F. poae. BEA was associated with the presence of F. tricinctum and, to a lesser extent, with the presence of F. poae. The use of genetic chemotype data revealed that DON concentrations were mostly influenced by DON-producing strains of F. graminearum and F. culmorum, whereas the concentrations of NIV were influenced by the number of NIV-producing strains of both species added to the number of F. cerealis and F. poae strains. This study emphasises the need to pay attention to less-studied Fusarium spp. for future Fusarium head blight management strategies, as they commonly co-occur in the field and are associated with a broad spectrum of mycotoxins.

Reporter gene assays incorporating nuclear receptors (estrogen, androgen, thyroid β and PPARγ2) have been implemented to assess the endocrine activity of 13 mycotoxins and their mixtures. As expected, zearalenone and its metabolites α-zearalenol and β- zearalenol turned out to have the strongest estrogenic potency (EC50 8,7 10-10 ± 0,8; 3,1 10-11 ± 0,5 and 1,3 10-8 ± 0,3 M respectively). The metabolite of deoxynivalenol, 3-acetyl-deoxynivalenol also had estrogenic activity (EC50 3,8 10-7 ± 1,1 M). Furthermore, most of the mycotoxins (and their mixtures) showed anti-androgenic effects (15-acetyldeoxynivalenol, 3-acetyl-deoxynivalenol and α-zearalenol with potencies within one order of magnitude of that of the reference compound flutamide). In particular, deoxynivalenol and 15-acetyl-deoxynivalenol acted as antagonists for the PPARy2 receptor. When testing mixtures of mycotoxins on the same cell systems, we showed that most of the mixtures reacted as predicted by the concentration addition (CA) theory. Generally, the CA was within the 95% confidence interval of the observed ones, only minor deviations were detected. Although these reporter gene tests cannot be directly extrapolated in vivo, they can be the basis for further research. Especially the additive effects of ZEN and its metabolites are of importance and could have repercussions in vivo.

Mycotoxins are harmful food contaminants. Currently, human exposure assessment to these toxins is often based on calculations combining mycotoxin occurrence data in food with population data on food consumption. Because of limitations inherent to that approach, biomarkers have been proposed as a suitable alternative whereby a more accurate assessment of exposure at the individual level can be performed. The BIOMYCO study is designed to assess human mycotoxin exposure using urinary biomarkers of exposure. Over the different seasons of 2013 and 2014, morning urine is gathered in a representative part of the Belgian population according to a designed study protocol, whereby 140 children (3-12 years old) and 278 adults (19-65 years old) are selected based on random cluster sampling stratified for sex, age and geographical areas. Every participant completes a food frequency questionnaire to assess the consumption of relevant foodstuffs (n = 43) of both the day before the urine collection and the previous month. Validated multi-toxin LC-MS/MS methods are used to analyse aflatoxins, fumonisins, ochratoxin A, trichothecenes, zearalenone and their metabolites in morning urine. The study protocol is approved by the ethical committee of the Ghent University Hospital. Within this paper, study design and methods are described. The BIOMYCO study is the first study whereby a multi-toxin approach is applied for mycotoxin exposure assessment in adults and children on a large scale. Moreover, it is the first study that will describe the exposure to an elaborated set of mycotoxins in the Belgian population. In first instance, descriptive analysis will be performed, describing the exposure to mycotoxins for the child and adult group. Exposure of different subgroups will be compared. Furthermore, correlations between the mycotoxin concentrations measured and the food consumption reported will be estimated to explore whether the mycotoxin exposure could be explained by the consumption of certain foods.

A direct, fast and sensitive LC–MS/MS method was developed to measure biomarkers for mycotoxin exposure in human urine. In total, 32 biomarkers were quantitatively or semi-quantitatively measured in 32 urine samples of Belgian volunteers using two injections. All urine samples contained deoxynivalenol-15-glucuronide, the major detoxification metabolite of deoxynivalenol, in the ng/mL range. Also deoxynivalenol-3-glucuronide and de-epoxy-deoxynivalenol-glucuronide were present in, respectively, 90 and 25 % of the samples, while deoxynivalenol was detected in 60 % of the samples, in lower concentrations. Deoxynivalenol glucuronides were the major biomarkers for deoxynivalenol exposure. Ochratoxin A was detected in 70 % of the samples in pg/mL. Citrinin and/or dihydrocitrinone were detected in 90 % of the samples, also in concentrations of pg/mL. The presence of ochratoxin A and citrinin was confirmed by a second method using sample cleanup by immunoaffinity columns, followed by LC–MS/MS. Our data show that humans are much more exposed to citrinin than realized before and suggest further work on citrinin exposure in relation with ochratoxin A exposure, as both mycotoxins are nephrotoxic.

Two separable anthocyanin acyltransferases were identified in cell cultures of Ajuga reptans which accumulate acylated cyanidin and delphinidin-based anthocyanins. One catalysed the transfer of hydroxycinnamic acids from their CoA-esters to cyanidin 3-sophoroside, anthocyanidin 3,5-diglucosides, anthocyanidin 3-sophoroside-5-glucosides and delphinidin 3-glucoside. The other transferred the malonyl moiety from malonyl-CoA preferably to anthocyanidin 3-coumaroylglucoside-5-glucosides and anthocyanidin 3-glucosides. Anthocyanidin 3,5-diglucosides, anthocyanidin 3-sophoroside-5-glucosides, anthocyanidin 3-biosides and cyanidin 3,3′-diglucoside were less effective substrates for the malonyltransferase. The substrate specificity was rather broad, as anthocyanins which were not detected in cell cultures or plants of A. reptans were acylated as well. In vitro the hydroxycinnamoyltransferase transferred only one acyl group per anthocyanin molecule, while in vivo the main anthocyanins of callus, suspension cultures and flowers of A. reptans contain two aromatic acyl groups per pigment molecule. The hydroxycinnamoyltransferase activity was totally absent in acyanic calli, while the malonyltransferase activity could be detected in two acyanic callus lines of A. reptans . The hydroxycinnamoyltransferase was inhibited by several divalent ions.

An LC-MS/MS method was developed and validated for the simultaneous determination of deoxynivalenol, zearalenone, T-2-toxin, HT-2-toxin and metabolites, including 3-acetyldeoxynivalenol, 15-acetyldeoxynivalenol, deoxynivalenol-3-glucoside, α-zearalenol, β-zearalenol, zearalenone-4-glucoside, α-zearalenol-4-glucoside, β-zearalenol-4-glucoside and zearalenone-4-sulfate in maize, wheat, oats, cornflakes and bread. Extraction was performed with acetonitrile/water/acetic acid (79/20/1, v/v/v) followed by a hexane defatting step. After filtration, the extract was evaporated and the residue was redissolved in mobile phase for injection. The mobile phase, which consisted of a mixture of methanol and water with 10 mM ammonium acetate, was adjusted to pH 3 with glacial acetic acid. A sample clean-up procedure was not included because of the low recoveries of free and masked mycotoxins and their differences in polarity. The method allowed the simultaneous determination of 13 Fusarium mycotoxins in a one-step chromatographic run using a Waters Acquity UPLC system coupled to a Quattro Premier XE mass spectrometer. The method was validated for several parameters such as linearity, apparent recovery, limit of detection, limit of quantification, precision, expanded measurement uncertainty and specificity. The limits of detection varied from 5 to 13 ng g−1; those for the limit of quantification from 10 to 26 ng g−1. The results of the performance characteristics of the developed LC-MS/MS method were in good agreement with the criteria mentioned in Commission Regulation (EC) No. 401/2006. Thirty samples of a variety of food and feed matrices were sampled and analysed between July 2010 and January 2011.

Seven commercially available deoxynivalenol (DON) and zearalenone (ZEN) immunoaffinity columns (IACs) were tested for cross-reactivity to conjugated forms (3-acetyl-deoxynivalenol, 15-acetyl-deoxynivalenol, DON-3-glucoside, DON-3-glucuronide, ZEN-glucosides, ZEN-glucuronide) and metabolites (de-epoxydeoxynivalenol, α-zearalenol, β-zearalenol) and nivalenol (NIV), using a semi-quantitative multi-mycotoxin ultra-performance liquid chromatography-tandem mass spectrometry method. The DON IACs showed cross-reactivity for nearly all DON derivatives tested. The ZEN IACs showed limited cross-reactivity to some of the ZEN derivatives. The IACs were evaluated for their potential use as sample clean-up for mycotoxins in serum.

Ginkgo biloba is a widely consumed dietary supplement. Some dietary active compounds modulate the activity of biotransformation enzymes inside the enterocytes and more interestingly of cytochrome P-450 1A1 (CYP1A1). This enzyme is of a particular interest because of its implication in the metabolism of some exogenous pro-carcinogens or endogenous molecules. In the present work, we have used Caco-2 cells to study the effect of a standard reference material of a Ginkgo biloba extract (GBE) (10400 μg/ml), as well as of its major individual active compounds (kaempferol, quercetin, isorhamnetin, ginkgolides and bilobalide), alone or in mixtures, at realistic intestinal concentrations, on the induction of CYP1A1 activity, in the presence or absence of benzo[a]pyrene (B[a]P) (0.1 μg/ml), a well-known CYP1A1 inducer. 3-O-rutinosides of kaempferol, quercetin and isorhamnetin were also tested. We have demonstrated a strong induction (p < 0.005) of CYP1A1 activity and a slight, but significant (p < 0.005), decrease of this activity in the presence of B[a]P by the GBE at the realistic exposure level of 100 μg/ml. The inductive effect was explained, in part, by quercetin and kaempferol after 24 h exposure while unknown compounds seem to be responsible for the strong CYP1A1 induction observed after 6 h exposure. The inhibitory potency of flavonols on CYP1A1 activity in presence of B[a]P was much stronger for the aglycones than for the 3-O-rutinosides, explaining the slight effect observed with the GBE, mainly composed of glycosylated flavonoids. These results indicate that GBEs may disturb intestinal CYP1A1 activity and, in turn, affect the metabolism of other compounds. The present paper thus highlights the necessity to take these side effects into account when administrating Ginkgo biloba herbal supplements.

The glucosinolate profile of black radish (Raphanus sativus L. niger) based dietary supplements has been investigated by HPLC-PDA, LC-ESI-MS/MS and LC-APCI-MS/MS systems. Optimization of the MS/MS parameters and LC conditions was performed using sinigrin reference standard and rapeseed certified reference material (BC190) respectively. An LC-ESI-MS/MS system was used to detect (screen) and identify the naturally occurring intact glucosinolates (GLs). The intact GLs identified were then desulfated and quantified on an HPLC-PDA system as desulfo-glucosinolates (DS-GLs). Prior to quantification, the DS-GLs were identified using an APCI-MS/MS. The HPLC-PDA method performance criteria were evaluated using glucotropaeolin potassium salt. The validated method was applied for the analysis of six dietary supplements. In total, six glucosinolates were identified and quantified in the dietary supplements; glucoraphasatin (0.20.48 mg/g), glucosisaustricin (0.370.91 mg/g), glucoraphenin (0.841.27 mg/g), glucoputrajivin (0.140.28 mg/g), glucosisymbrin (0.700.99 mg/g) and gluconasturtiin (0.060.12 mg/g). Glucoraphenin was the most abundant glucosinolate in all samples.

A multi-analyte method for the liquid chromatography-tandem mass spectrometric determination of mycotoxins in food supplements is presented. The analytes included A and B trichothecenes (nivalenol, deoxynivalenol, 3-acetyldeoxynivalenol, 15-acetyldeoxynivalenol, neosolaniol, fusarenon-X, diacetoxyscirpenol, HT-2 toxin and T-2 toxin), aflatoxins (aflatoxin-B(1), aflatoxin-B(2), aflatoxin-G(1) and aflatoxin-G(2)), Alternaria toxins (alternariol, alternariol methyl ether and altenuene), fumonisins (fumonisin-B(1), fumonisin-B(2) and fumonisin-B(3)), ochratoxin A, zearalenone, beauvericin and sterigmatocystin. Optimization of the simultaneous extraction of these toxins and the sample pretreatment procedure, as well as method validation were performed on maca (Lepidium meyenii) food supplements. The results indicated that the solvent mixture ethyl acetate/formic acid (95:5, v/v) was the best compromise for the extraction of the analytes from food supplements. Liquid-liquid partition with n-hexane was applied as partial clean-up step to remove excess of co-extracted non-polar components. Further clean-up was performed on Oasis HLB cartridges. Samples were analysed using an Acquity UPLC system coupled to a Micromass Quattro Micro triple quadrupole mass spectrometer equipped with an electrospray interface operated in the positive-ion mode. Limits of detection and quantification were in the range of 0.3-30 ng g(-1) and 1-100 ng g(-1), respectively. Recovery yields were above 60% for most of the analytes, except for nivalenol, sterigmatocystine and the fumonisins. The method showed good precision and trueness. Analysis of different food supplements such as soy (Glycine max) isoflavones, St John's wort (Hypericum perforatum), garlic (Allium sativum), Ginkgo biloba, and black radish (Raphanus niger) demonstrated the general applicability of the method. Due to different matrix effects observed in different food supplement samples, the standard addition approach was applied to perform correct quantitative analysis. In 56 out of 62 samples analysed, none of the 23 mycotoxins investigated was detected. Positive samples contained at least one of the toxins fumonisin-B(1), fumonisin-B(2), fumonisin-B(3) and ochratoxin A.

Four anthocyanins from Ajuga reptans flowers and its cell cultures were isolated, and a fifth was also characterized by HPLC-mass spectrometry. By means of chemical and spectroscopic analyses, their structures were identified as delphinidin 3-(p-coumaroyl-feruloyl)sophoroside-5-malonylglucoside, delphinidin 3-(diferuloyl)sophoroside-5-malonylglucoside, and cyanidin 3-(di-p-coumaroyl)sophoroside-5-glucoside, respectively. The other two were tentatively identified as delphinidin 3-(diferuloyl)sophoroside-5-glucoside and cyanidin 3-(feruloyl-p-coumaroyl)sophoroside-5-malonylglucoside. In neutral aqueous solution, the crude extract from A. reptans flower cell cultures and the major anthocyanin cyanidin 3-(di-p-coumaroyl)sophoroside-5-malonylglucoside were more stable than cyanidin 3-glucoside, and also prevented more efficiently peroxidation than did the latter. A. reptans flower cell culture anthocyanins may have a potential as natural colorants for food utilities or other purposes.

Four anthocyanins were isolated from Ajuga reptans flowers and one from the cell cultures. By FAB mass spectrometry measurements, the structures of these pigments were determined as delphinidin and cyanidin glucosides acylated with two cinnamic acids, while three of them were also malonylated. A delphinidin-based pigment in the crude extract from cell cultures was identical to the major flower pigment as shown by HPLC co-chromatography. Moreover, by application of 1H and 13C NMR consisting of DQF-COSY, NOESY, ROESY, 2D-HOHAHA, HSQC and HMBC methods, the structures of two new anthocyanins were identified as delphinidin and cyanidin 3-O-(2-O-(6-O-(E)-p- coumaryl-β- d -glucopyranosyl )-(6-O-(E)-p- coumaryl)-β- d -glucopyranosyl )-5-O-(6-O- malonyl-β- d -glucopyranoside ) . The deacylated anthocyanins were confirmed as delphinidin and cyanidin 3-sophoroside-5-glucosides.

Ginkgo biloba is largely consumed as food supplement, because it could contribute to memory improvement by acting on cerebrovascular insufficiency. Among the large variety of phytochemicals contained in Ginkgo biloba leaves and extracts, flavonols (mainly kaempferol, quercetin and isorhamnetin) represent the largest part. Several unique terpenoids (ginkgolides A, B, C, J and bilobalide) are also present. In the present study, we investigated the modulation of cytochrome P450 (CYP) 1A1 enzymatic activity and expression in the intestinal Caco-2 cell line by either Ginkgo biloba extracts, by major individual secondary metabolites or by mixtures of these constituents in realistic proportions. Plausible used intestinal concentrations were calculated on the basis of recommended daily intake and quantitative analysis of major constituents in dietary supplements. Preliminary results suggest that (−)-bilobalide, but not the other terpenoids, induces a dose-dependent increase of CYP1A1 activity (measured through 7-ethoxyresorufin O-deethylation, EROD) after 6 h treatment of the Caco-2 cells. RT-PCR highlighted an increase of mRNA after 3 h treatment with (−)-bilobalide, suggesting the involvement of a transcriptional mechanism. Furthermore, a strong dose-dependent inhibition of benzo[a]pyrene (B[a]P)-induced EROD activity was shown after 6 h co-treatment with kaempferol, quercetin or isorhamnetin. This antagonistic effect was conserved with mixtures of the three flavonols and of the eight pre-cited major secondary metabolites. These preliminary results suggest that frequent consumption of Ginkgo biloba-based dietary supplements may influence CYP1A1 expression and activity in intestinal cells, leading to possible toxicological interactions.

Lactose utilisation by cucumber cell suspension cultures starts only after a long lag phase and is accompanied by an increase of an extracellular lactosespecific β-galactosidase activity. Supplementing the lactose medium with sucrose shortens the lag phase. Milk whey permeate seems to contain a factor(s) which inhibits lactose utilisation. After supplementing the medium with sucrose or its hydrolysis products, growth and substrate utilisation is as efficient as in Murashige and Skoog medium. Galactose also induces growth, but growth and substrate utilisation are slower. In whey medium, supplemented with sucrose, the extracellular β-galactosidase activity again accompanies growth induction.