Curcumin mitigates ochratoxin A-induced oxidative stress and alters gene expression in broiler chicken liver and kidney.

The study aimed to evaluate the effect of curcumin (CURC) supplementation on broiler chickens exposed to ochratoxin A (OTA), by examining biochemical parameters and the expression of glutathione redox system genes and their regulation. OTA reduced glutathione content in the liver while increasing glutathione peroxidase activity. CURC showed no significant effects. Kidney parameters remained mostly unaffected. Gene expression analysis revealed OTA-induced upregulation of KEAP1, NRF2, AHR, GPx4 and GSR genes in the liver. CURC supplementation led to the upregulation of GPx4 and AHR genes with OTA+CURC treatment, resulting in the downregulation of GPx4, KEAP1, NRF2 and AHR genes compared to OTA treatment alone. In the kidney, GPx4 was downregulated, and NRF2 and AHR were upregulated as an effect of OTA, while CURC upregulated the NRF2 gene only. OTA+CURC treatment led to the downregulation of GPx4, GSS and AHR genes compared to the control and downregulation of NRF2 and AHR genes compared to OTA. The results suggested that CURC is partly effective against OTA-induced oxidative stress and that the effect of OTA and CURC on the antioxidant response is regulated through the KEAP1-NRF2-ARE and AHR pathways.

Role of the glutathione redox system in the susceptibility of pheasants (Phasianus colchicus) to ochratoxin A.

The purpose of the present study was to investigate the effects of different dietary concentrations of ochratoxin A (OTA) on the growth, feed intake, mortality, blood plasma protein content and some parameters of lipid peroxidation and the glutathione redox system of pheasant chicks in a three-week long trial. A total of 320 seven-day-old female pheasants were randomly assigned to four treatment groups (n = 40 in each), fed with a diet artificially contaminated with OTA [control (<0.02 mg/kg), 0.88 mg/kg, 1.14 mg/kg and 1.51 mg/kg] for 21 days (up to 28 days of age). The pheasant chicks were sacrificed at early (12, 24 and 72 h) and late (7, 14 and 21 days) stages of mycotoxin exposure to check the effect of OTA. Minimal feed refusal was found in the medium- and high-dose toxin groups (-9.8 and -7.9%, respectively), and body weight gain was nearly the same in all groups. The glutathione redox system was activated mainly in the liver, confirmed by significantly increased reduced glutathione content and glutathione peroxidase activity during the late phase of mycotoxin exposure and at a high-dose treatment. The results suggest that pheasants have low susceptibility to OTA, and activation of the glutathione redox system has importance in this tolerance.

Modification of the effects of aflatoxin B1 on the glutathione system and its regulatory genes by zeolite.

The purpose of the present study was to use oxidative stress markers for investigating the effect of zeolite (315 mg/kg of complete feed) in the case of aflatoxin B1 contamination (92 µg/kg complete feed). In a 21-day feeding trial with broiler chickens, oxidative stress parameters such as conjugated dienes, conjugated trienes, malondialdehyde, reduced glutathione content and glutathione peroxidase activity were not changed significantly by supplementation with this mycotoxin absorbent. The relative gene expression of transcription factors KEAP1 and NRF2 was not modified by the absorbent either. Still, the expression of GSS, GSR and GPX4 genes increased significantly due to the aluminosilicate supplementation. The results suggest that zeolite reduced lipid peroxidation in the blood plasma but not in the red blood cell haemolysate or the kidney. The relative expression of the genes encoding the glutathione redox system also changed as a result of zeolite supplementation, but these changes were not found at the protein level.

Wild Strawberry, Blackberry, and Blueberry Leaf Extracts Alleviate Starch-Induced Hyperglycemia in Prediabetic and Diabetic Mice.

Intestinal α-glucosidase and α-amylase break down nutritional poly- and oligosaccharides to monosaccharides and their activity significantly contributes to postprandial hyperglycemia. Competitive inhibitors of these enzymes, such as acarbose, are effective antidiabetic drugs, but have unpleasant side effects. In our ethnopharmacology inspired investigations, we found that wild strawberry (Fragaria vesca), blackberry (Rubus fruticosus), and European blueberry (Vaccinium myrtillus) leaf extracts inhibit α-glucosidase and α-amylase enzyme activity in vitro and are effective in preventing postprandial hyperglycemia in vivo. Toxicology tests on H9c2 rat embryonic cardiac muscle cells demonstrated that berry leaf extracts have no cytotoxic effects. Oral administration of these leaf extracts alone or as a mixture to normal (control), obese, prediabetic, and streptozotocin-induced diabetic mice attenuated the starch-induced rise of blood glucose levels. The efficiency was similar to that of acarbose on blood glucose. These results highlight berry leaf extracts as candidates for testing in clinical trials in order to assess the clinical significance of their effects on glycemic control.

Combined effects of aflatoxin B1 and deoxynivalenol on the expression of glutathione redox system regulatory genes in common carp.

The purpose of the present study was to evaluate the short-term effects of aflatoxin B1 (AFB1 ) and deoxynivalenol (DON) exposure on the expression of the genes encoding the glutathione redox system glutathione peroxidase 4a (gpx4a), glutathione peroxidase 4b (gpx4b), glutathione synthetase (gss) and glutathione reductase (gsr) and the oxidative stress response-related transcription factors Kelch-like ECH-associated protein 1 (keap1) and nuclear factor-erythroid 2 p45-related factor 2 (nrf2) in liver, kidney and spleen of common carp. During the 24-hr long experiment, three different doses (5 µg AFB1 and 110 µg DON; 7.5 µg AFB1 and 165 µg DON or 10 µg AFB1 and 220 µg DON/kg bw) were used. The results indicated that the co-exposure of AFB1 and DON initiated free radical formation in liver, kidney and spleen, which was suggested by the increase in Nrf2 dependent genes, namely gpx4a, gpx4b, gss and gsr. Expression of keap1 gene showed upregulation after 8 hr of mycotoxin exposure, and also upregulation of nrf2 gene was found in kidney after 8 hr of exposure, while in the liver, only slight differences were observed. The changes in the expression of the analysed genes suggest that level of reactive oxygen species reached a critical level where other signalling pathway was activated as described by the hierarchical model of oxidative stress.

Short-term effects of deoxynivalenol, T-2 toxin, fumonisin B1 or ochratoxin on lipid peroxidation and glutathione redox system and its regulatory genes in common carp (Cyprinus carpio L.) liver.

The effects of a single oral dose of 1.82 mg kg-1 bw of T-2 and HT-2 toxin (T-2), 1.75 mg kg-1 bw deoxynivalenol (DON) and 15-acetyl DON, 1.96 mg kg-1 bw fumonisin B1 (FB1) or 1.85 mg kg-1 bw ochratoxin A (OTA) were investigated in common carp juveniles on lipid peroxidation, the parameters of the glutathione redox system including the expression of their encoding genes in a short-term (24 h) experiment. Markers of the initiation phase of lipid peroxidation, conjugated dienes, and trienes, were slightly affected by DON and OTA treatment at 16-h sampling. The termination marker, malondialdehyde, concentration increased only as an effect of FB1. Glutathione content and glutathione peroxidase activity showed significantly higher levels in the T-2 and FB1 groups at 8 h, and in the DON and FB1 groups at 16 h. The expression of glutathione peroxidase genes (gpx4a, gpx4b) showed a dual response. Downregulation of gpxa was observed at 8 h, as the effect of DON, FB1, and OTA, but an upregulation in the T-2 group. At 16 h gpx4a upregulated as an effect of DON, T-2, and FB1, and at 24 h in the DON and T-2 groups. Expression of gpx4b downregulated at 8 h, except in the T-2 group, and upregulation observed as an effect of T-2 at 24 h. The lack of an increase in the expression of nrf2, except as the effect of DON at 8 h, and a decrease in the keap1 expression suggests that the antioxidant defence system was activated at gene and protein levels through Keap1-Nrf2 independent pathways.

Interaction between the three frequently co-occurring Fusarium mycotoxins in rats.

To test the complex, acute biochemical effects of combined, naturally co-occurring fusariotoxins, a 5-day rat study was performed. Mycotoxin treatment was invented by intraperitoneal injection: FB1 (F): 9 µg/animal/day (approx. 30 µg/kg bw/day), DON (D): 16.5 µg/animal/day (approx. 55 µg/kg bw/day) and ZEN (Z): 12.75 µg/animal/day (approx. 42.5 µg/kg bw/day). The binary groups (FB1 and DON [FD], FB1 and ZEN [FZ] and DON and ZEN [DZ]) as well as the ternary (FB1 , DON and ZEN [FDZ]) group were dosed at the same combined level as the individual mycotoxins. Body weight, feed intake and mortality were not affected by any of the treatments. FB1 and DON in combination (FD) increased the plasma aspartate aminotransferase activity synergistically (compared to the individual FB1 and DON). In the liver, both the total glutathione (GSH) and the glutathione peroxidase (GPx) activity were increased (p < 0.05) by the binary FB1 and ZEN (FZ) and the DON and ZEN (DZ) groups as well as the ternary FB1 , DON and ZEA group (FDZ) compared to the control. The GSH level of the ternary group was significantly increased compared to the FB1 group, whereas the GPx activity of the ternary group was significantly increased compared to all three the individual mycotoxin groups. The Bliss independence method revealed synergism between DON and ZEN (DZ), as well as FB1 and DON (FD) on liver GPx activity. None of the toxins alone or in combination exerted strong genotoxicity on lymphocytes, neither on the gross histopathological characteristics. However, even at these low levels acute exposure of more than one of these mycotoxins (FB1 , DON and ZEN) affected metabolic and detoxification changes.

Fumonisin B1 exposure increases Hsp70 expression in the lung and kidney of rats without inducing significant oxidative stress.

The objective of this experiment was to determine whether fumonisin B1 (FB1) added to the diet of rats in a dose of 50 mg/kg changes the production of heat shock protein 70 (Hsp70) in the lungs and kidney of rats. We also studied the effect of this mycotoxin on the antioxidant system of the body. Mature (8 weeks old) male Wistar Crl:WI BR rats (n = 6/group) were fed the toxin-containing diet for 5 days. FB1 resulted in a 7% body weight reduction without significantly changing the feed intake. Western blot analysis of the lungs and kidney demonstrated a substantial (1.4-fold and 1.8-fold, respectively) increase in Hsp70 expression. Alterations could not be detected in the clinical chemical parameters (total protein, albumin, total cholesterol, glucose, creatinine and urea concentrations, and aspartate aminotransferase activity). There was no statistically significant change in malondialdehyde concentrations and the measured antioxidant parameters (the amount of reduced glutathione, GSH and glutathione peroxidase activity, GPx) in the blood plasma, lung and kidney tissue. Thus, it can be concluded that FB1 did not induce oxidative stress in the lungs and kidney, but increased Hsp70 production.

Short-term effects of T-2 toxin or deoxynivalenol on glutathione status and expression of its regulatory genes in chicken.

Short-term (48-hour) effects of 3.74/1.26 mg kg-1 T-2/HT-2 toxin or 16.12 mg kg-1 DON in feed were investigated in the liver of three-week-old cockerels (body weight: 749.60 ± 90.98 g). Markers of lipid peroxidation showed no significant changes. At hour 24, glutathione content in the T-2/HT-2 toxin group was significantly higher than in the control. Glutathione peroxidase activity was significantly higher than the control at hour 24 in the T-2/H-2 toxin group and at hour 48 in the DON group. In the DON group, expression of the glutathione peroxidase 4 gene (GPX4) was significantly lower than in the control at hours 12 and 14, and higher at hour 48. Expression of the glutathione reductase gene (GSR) was significantly lower than in the control at hour 12 in the T-2/HT-2 toxin group, and at hours 12, 24 and 48 in the DON group. However, at hour 36 higher GSR expression was measured in the DON group. Due to the effect of both trichothecenes, expression of the glutathione synthetase gene (GSS) was significantly lower than in the control at hours 24 and 48. In conclusion, T-2/HT-2 toxin and DON had a moderate short-term effect on free radical formation. T-2/HT-2 toxin induced more pronounced activation of the glutathione redox system than did DON.

[Antioxidant effect of the fibre content of foods]. / Az élelmiszerek rosttartalmának antioxidáns hatása.

Antioxidants have some health benefit, but up to now there was less attention paid to the antioxidant properties of dietary fibre. The antioxidant effect of dietary fibre is based on the polyphenol compounds bound to polysaccharide complexes, which are released in the gut and functioning as antioxidants. Another type of antioxidant, calcium fructoborate was also isolated from plant cell wall. It has a marked antioxidant capacity, however, its active component is not a polyphenol, but the boron. There are lots of food plants which have relatively high antioxidant dietary fibre content, thus they support the antioxidant defence of the gastrointestinal tract, and consequently the whole body. The important ones in human nutrition are for instance cereal grains, cabbage, grape pomace, coffee bean or guava. There are different polyphenol compounds in the antioxidant dietary fibres in the plants, therefore their antioxidant capacity varies, but it is approximately equivalent to 50-100 mg DL-α-tocopherol per gram. This antioxidant capacity is considerable, and would be suitable for the prevention of some, oxidative stress-related diseases, such as atherosclerosis or other cardiovascular diseases, and colorectal carcinoma. Orv Hetil. 2018; 159(18): 709-712.

Flow cytometry based rapid duplexed immunoassay for fusarium mycotoxins.

At small food processing facilities, the most frequently used test to determine if grain-derived mycotoxin concentrations are compliant with legal limits is the enzyme-linked immunosorbent assay (ELISA). Each kit is designed to detect one of the six dangerous mycotoxins. With the increasing occurrence of coinfection of grain with multiple-mycotoxins in the field and/or during storage, ELISA is no longer a cost effective best assay option. With ELISA, each species of mycotoxin requires different sample preparation/extraction and a 45 min incubation. The alternative multiplexed assay presented here, the competitive fluorescent microsphere immunoassay (CFIA), follows current food safety standards. It handles several toxins simultaneously with a single universal extraction protocol. The authors' objective was to modify an existing commercial CFIA kit developed for bench top flow cytometry and extend its utility for point-of-need (PON) applications. The accelerated protocol offers over 60% reduction in total processing time and it detects dual mycotoxin contamination simultaneously. The observed enhanced binding kinetics equations reported here utilizing suspended solid phase particles in liquid phase, are also supported by published theoretical calculations. In the near future portable cytometry may bring rapid multiplexed PON testing to assure the safety of small food processing installations. © 2016 International Society for Advancement of Cytometry.

Acute hepatic effects of low-dose fumonisin B(1) in rats.

Adult male Wistar rats were enrolled in a study to test the acute hepatic effects of 50 mg/kg fumonisin B1 in feed for 5 days. Fumonisin B1 depressed growth and feed intake, and absolute and relative liver weight showed a significant increase. The proportions of C17:0, C18:3 n3, C22:5 n3 and C22:6 n3 fatty acids decreased in the hepatic phospholipid fraction. All proportional decreases modified the hepatocellular membrane lipids into a more rigid state. The fatty acid profile modifications were partly compensated for by endogenous glutathione (preventing the formation of conjugated dienes and trienes as initial phase lipid peroxidation indicators), while the enzymatic antioxidant defence system (glutathione peroxidase) was unaltered. In contrast, hepatic malondialdehyde, the cytotoxic product of end-phase lipid peroxidation showed a concentration increase even after 5 days of feeding. The results indicate a rather strong and rapid hepatic effect of FB1, immediately impairing membrane phospholipids, even before the enzymatic antioxidant defence is activated.

Short-term effects of T-2 toxin or deoxynivalenol on lipid peroxidation and the glutathione system in common carp.

The purpose of this study was to investigate the short-term effects of a single oral dose of T-2 and HT-2 toxin at 0.15, 0.33 and 1.82 mg kg-1 body weight, or deoxynivalenol (DON) and 15-acetyl-DON at 0.13, 0.31 and 1.75 mg kg-1 body weight in common carp. Conjugated dienes and trienes (the early markers of lipid peroxidation) were elevated in all DON-treated groups at the 16th hour, while thiobarbituric acid reactive substances (TBARS; termination marker) were increased at the highest dose of DON at the 16th and 24th hours. T-2 toxin did not cause changes in these parameters. Glutathione content and glutathione peroxidase activity showed higher levels at the 16th hour as the effect of both mycotoxins. The expression of glutathione peroxidase (GPx4) genes (gpx4a and gpx4b) revealed a dual response. Downregulation was observed at the 8th hour, followed by an induction at the 16th hour, at the lowest dose of both mycotoxins. Higher doses revealed long-drawn emergence and an elevation was observed only at the 24th hour. However, at the lowest and highest doses of DON or T-2 toxin the changes in gene expression were delayed, which may be related to the low oxidative stress response, as suggested by the expression profiles of the nrf2, keap1, gpx4a and gpx4b genes.

Effects of subclinical Mycobacterium avium ssp. paratuberculosis infection on some physiological parameters, health status and production in dairy cows.

Milk yield, milk ingredients, health and other, production-related parameters of subclinically infected, Mycobacterium avium ssp. paratuberculosis (MAP-) shedding (positive faecal PCR, n = 20) and non-shedding (negative faecal PCR, n = 10) dairy cows were compared in the period from 10 days prepartum to 120 days postpartum. Body condition, rumen fill and faeces scores were lower in the MAP-shedding cows. There was no significant difference in plasma or urine metabolic parameters between the groups. Milk yield and lactose content tended to be lower (P = 0.074 and 0.077, respectively), somatic cell count tended to be higher (P = 0.097), while milk fat content was significantly higher (P = 0.006) in MAP-shedding cows than in the controls. Milk protein content did not differ between the groups. All other health and production parameters [number of reproductive tract treatments, number of udder treatments, number of artificial inseminations (AIs), calving interval, and service period] were significantly better in the control group. It is concluded that MAP infection, even in a subclinical form, has a significant impact on some production and health parameters of dairy cows.

Multi-Fusarium mycotoxin exposure activates Nrf2 and Ahr pathway in the liver of laying hens.

This study investigates gene expression changes in laying hens exposed to trichothecene mycotoxins, known to induce oxidative stress and affect xenobiotic transformation and antioxidants. A 3-day feeding trial tested low and high doses of T-2/HT-2 toxin, DON/3-AcDON/15-AcDON, and FB1 in hen feed. Results showed increased expression of AHR, AHRR, HSP90, and CYP1A2 genes on days 2 and 3, suggesting a response to mycotoxin exposure. High doses down-regulated CYP1A2, AHR, and AHRR on day 1. KEAP1 expression decreased on day 1 but increased dose-dependently on days 2 and 3. NRF2 was up-regulated by low and down-regulated by high doses on day 1, then increased on days 2 and 3. Antioxidant-related genes (GPX3, GPX4, GSS, GSR) showed dose-dependent responses. Low doses up-regulated GPX3 and GPX4 throughout, while high doses up-regulated GPX3 on days 2 and 3 and GPX4 on day 3. GSS was up-regulated on day 3. Results indicate that toxic metabolites formed by phase I biotransformation rapidly induce ROS formation at low doses through the AHR/Hsp90/CYP1A2 pathway at the gene expression level, but at high levels, ROS-induced oxidative stress manifests later. Study showed simultaneous activation of redox-sensitive pathways: aryl hydrocarbon receptor (Ahr) and nuclear factor erythroid-derived 2-like 2 (Nrf2) by multi-mycotoxin exposure.

The Effects of T-2 Toxin, Deoxynivalenol, and Fumonisin B1 on Oxidative Stress-Related Genes in the Kidneys of Laying Hens.

In the context of nephrotoxic risks associated with environmental contaminants, this study focused on the impact of mycotoxin exposure on the renal health of laying hens, with particular attention to oxidative stress pathways. Sixty laying hens were assigned to three groups-a control group (CON), a low-dose mycotoxin group (LOW), and a high-dose mycotoxin group (HIGH)-and monitored for 72 h. Mycotoxin contamination involved T-2/HT-2 toxin, DON/3-AcDON/15-AcDON, and FB1 at their EU-recommended levels (low mix) and at double doses (high mix). Clinical assessments revealed no signs of toxicity or notable weight changes. Analysis of the glutathione redox system parameters demonstrated that the reduced glutathione content was lower than that in the controls at 48 h and higher at 72 h. Glutathione peroxidase activity increased in response to mycotoxin exposure. In addition, the gene expression patterns of key redox-sensitive pathways, including Keap1-Nrf2-ARE and the AhR pathway, were examined. Notably, gene expression profiles revealed dynamic responses to mycotoxin exposure over time, underscoring the intricate interplay of redox-related mechanisms in the kidney. This study sheds light on the early effects of mycotoxin mixtures on laying hens' kidneys and their potential for oxidative stress.

Exposure to a Combination of Fusarium Mycotoxins Leads to Lipid Peroxidation and Influences Antioxidant Defenses, Fatty Acid Composition of Phospholipids, and Renal Histology in Laying Hens.

The effects of combined short-term (3 days) exposure to Fusarium mycotoxins at both the EU recommended limit (T-2/HT-2 toxin: 0.25 mg/kg; DON/3-AcDON/15-AcDON: 5 mg/kg; FB1: 20 mg/kg) and twice the dose (T-2/HT-2 toxin: 0.5 mg/kg, DON/3-AcDON/15-AcDON: 10 mg/kg, and FB1: 40 mg/kg feed) on the kidneys of laying hens were examined. Our study aimed to investigate how these mycotoxins interacted with membrane lipid fatty acid (FA) composition and lipid peroxidation processes. It was observed that the levels of conjugated dienes and trienes were higher than the control in the low-mix group on day 3, and malondialdehyde concentration was higher on days 2 and 3. The proportion of phospholipid (PL) FAs showed that saturated and monounsaturated FAs increased. Still, both n3 and n6 polyunsaturated FAs decreased significantly on day 2 of exposure in the high-mix group. Among the n3 FAs, the level of docosahexaenoic (C22:6 n3) and among n6 FAs, arachidonic (C20:4 n6) acids decreased mainly on day 2 in the high-mix group. The results suggest that the combined exposure to Fusarium mycotoxins induced lipid peroxidation in the kidneys of laying hens, which resulted in marked changes in the PL FA profile. Histological examination revealed time- and dose-dependent increases as consequences of mycotoxin exposure.

The Possible Role of Mycotoxins in the Pathogenesis of Endometrial Cancer.

Endometrial cancer is one of the most common cancer types among women. Many factors can contribute to the development of this disease, including environmental factors and, thus, eating habits. Our study aims to determine the levels of various mycotoxins and their metabolites in the blood serum and endometrial tissue samples of participants with previously proven endometrial cancer and to find possible contributions to cancer development. In the cohort clinical trial, 52 participants aged between 44 and 86 were studied. The participants were divided into two groups: patients or matched controls. All patients had previously histologically diagnosed endometrial cancer. The cancer patients were divided into low-grade endometrioid and low- plus high-grade endometrioid groups. Controls had no history of endometrial malignancy or premalignancy. Blood serum and endometrial tissue samples were obtained from all study patients. We compared the concentrations of total Aflatoxins (Afs), Deoxynivalenol (DON), Ochratoxin-A (OTA), T2-toxin and HT2 toxin (T2/HT2 toxin), Zearalenone (ZEN), alpha-Zearalenol (α-ZOL), and Fumonisin B1 (FB1) in the serum and endometrium between the different study groups. As a result, we can see a significant correlation between the higher levels of Afs and zearalenone and the presence of endometrial cancer. In the case of Afs, DON, OTA, T2/HT2 toxins, ZEN, and alpha-ZOL, we measured higher endometrial concentrations than in serum. Considering the effect of mycotoxins and eating habits on cancer development, our results might lead to further research exploring the relationship between certain mycotoxins and endometrium cancer.

The Effect of Combined Exposure of Fusarium Mycotoxins on Lipid Peroxidation, Antioxidant Defense, Fatty Acid Profile, and Histopathology in Laying Hens' Liver.

Fumonisin B1, T-2 toxin, and deoxynivalenol are frequently detected in feed materials. The mycotoxins induce free radical formation and, thereby, lipid peroxidation. The effects of mycotoxin exposure at the EU recommended limit (T-2/HT-2 toxin: 0.25 mg/kg; DON = 3AcDON/15-AScDON: 5 mg/kg; fumonisin B1: 20 mg/kg) and double dose (T-2/HT-2 toxin: 0.5 mg/kg, DON/3-AcDON/15-AcDON: 10 mg, and FB1: 40 mg/kg feed) were investigated during short-term (3 days) per os exposure in the liver of laying hens. On day 1 higher while on day 3 lower MDA concentrations were found in the low-dose group compared to the control. Fatty acid composition also changed: the proportion of monounsaturated fatty acids increased (p < 0.05) and the proportion of polyunsaturated fatty acids decreased by day 3. These alterations resulted in a decrease in the index of unsaturation and average fatty acid chain length. Histopathological alterations suggested that the incidence and severity of liver lesions were higher in the mycotoxin-treated laying hens, and the symptoms correlated with the fatty acid profile of total phospholipids. Overall, the findings revealed that mycotoxin exposure, even at the EU-recommended limits, induced lipid peroxidation in the liver, which led to changes in fatty acid composition, matched with tissue damage.

Collision-induced dissociation of aflatoxins.

RATIONALE: The aflatoxin mycotoxins are particularly hazardous to health when present in food. Therefore, from an analytical point of view, knowledge of their mass spectrometric properties is essential. The aim of the present study was to describe the collision-induced dissociation behavior of the four most common aflatoxins: B1, B2, G1 and G2. METHODS: Protonated aflatoxins were produced using atmospheric pressure chemical ionization (APCI) mass spectrometry (MS) combined with high-performance liquid chromatography (HPLC). For the tandem mass spectrometry (MS/MS) experiments nitrogen was used as the collision gas and the collision energies were varied in the range of 9-44 eV (in the laboratory frame). RESULTS: The major APCI-MS/MS fragmentations of protonated aflatoxins occurred at 30 eV collision energy. The main fragmentation channels were found to be the losses of a series of carbon monoxide molecules and loss of a methyl radical, leading to the formation of radical-type product ions. In addition, if the aflatoxin molecule contained an ether- or lactone-oxygen atom linked to a saturated carbon atom, loss of a water molecule was observed from the [M + H](+) ion, especially in the case of aflatoxins G1 and G2. CONCLUSIONS: A relatively small modification in the structure of aflatoxins dramatically altered the fragmentation pathways and this was particularly true for aflatoxins B1 and B2. Due to the presence of a C = C double bond connected to the ether group in aflatoxin B1 no elimination of water was observed but, instead, formation of radical-type product ions occurred. Fragmentation of protonated aflatoxin B1 yielded the most abundant radical-type cations.