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Toxins Mar 2023Small grain cereals are frequently infected with mycotoxigenic fungi. Oats have a particularly high risk of contamination with type A trichothecene mycotoxins; their...
Small grain cereals are frequently infected with mycotoxigenic fungi. Oats have a particularly high risk of contamination with type A trichothecene mycotoxins; their glucoside conjugates have also been reported. Agronomy practices, cereal variety and weather conditions have been suggested to play a role in infection in oats. The current study investigates concentrations of free and conjugated mycotoxins in organic and conventional oats grown in Scotland. In 2019, 33 milling oat samples (12 organic, 21 conventional) were collected from farmers across Scotland, together with sample questionnaires. Samples were analysed for 12 mycotoxins (type A trichothecenes T-2-toxin, HT-2-toxin, diacetoxyscirpenol; type B trichothecenes deoxynivalenol, nivalenol; zearalenone and their respective glucosides) using LC-MS/MS. The prevalence of type A trichothecenes T-2/HT-2 was very high (100% of conventional oats, 83% of organic oats), whereas type B trichothecenes were less prevalent, and zearalenone was rarely found. T-2-glucoside and deoxynivalenol-glucoside were the most prevalent conjugated mycotoxins (36 and 33%), and co-occurrence between type A and B trichothecenes were frequently observed (66% of samples). Organic oats were contaminated at significantly lower average concentrations than conventional oats, whereas the effect of weather parameters were not statistically significant. Our results clearly indicate that free and conjugated T-2- and HT-2-toxins pose a major risk to Scottish oat production and that organic production and crop rotation offer potential mitigation strategies.
Topics: Mycotoxins; Avena; Edible Grain; Zearalenone; Chromatography, Liquid; Trichothecenes, Type B; Food Contamination; Tandem Mass Spectrometry; T-2 Toxin; Scotland; Glucosides; Fusarium
PubMed: 37104186
DOI: 10.3390/toxins15040247 -
Toxins Mar 2021Multiple mycotoxins were tested in milled rice samples ( = 200) from traders at different milling points within the Mwea Irrigation Scheme in Kenya. Traders provided the...
Multiple mycotoxins were tested in milled rice samples ( = 200) from traders at different milling points within the Mwea Irrigation Scheme in Kenya. Traders provided the names of the cultivar, village where paddy was cultivated, sampling locality, miller, and month of paddy harvest between 2018 and 2019. Aflatoxin, citrinin, fumonisin, ochratoxin A, diacetoxyscirpenol, T2, HT2, and sterigmatocystin were analyzed using ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Deoxynivalenol was tested using enzyme-linked immunosorbent assay (ELISA). Mycotoxins occurred in ranges and frequencies in the following order: sterigmatocystin (0-7 ppb; 74.5%), aflatoxin (0-993 ppb; 55.5%), citrinin (0-9 ppb; 55.5%), ochratoxin A (0-110 ppb; 30%), fumonisin (0-76 ppb; 26%), diacetoxyscirpenol (0-24 ppb; 20.5%), and combined HT2 + T2 (0-62 ppb; 14.5%), and deoxynivalenol was detected in only one sample at 510 ppb. Overall, low amounts of toxins were observed in rice with a low frequency of samples above the regulatory limits for aflatoxin, 13.5%; ochratoxin A, 6%; and HT2 + T2, 0.5%. The maximum co-contamination was for 3.5% samples with six toxins in different combinations. The rice cultivar, paddy environment, time of harvest, and millers influenced the occurrence of different mycotoxins. There is a need to establish integrated approaches for the mitigation of mycotoxin accumulation in the Kenyan rice.
Topics: Animal Feed; Animals; Chromatography, High Pressure Liquid; Crops, Agricultural; Cross-Sectional Studies; Food Handling; Food Microbiology; Fungi; Humans; Kenya; Mycotoxins; Oryza; Risk Assessment; Spectrometry, Mass, Electrospray Ionization; Tandem Mass Spectrometry
PubMed: 33799626
DOI: 10.3390/toxins13030203 -
Toxins Jun 2022Oat is susceptible to several Fusarium species that cause contamination with different trichothecene mycotoxins. The molecular mechanisms behind Fusarium resistance in...
Oat is susceptible to several Fusarium species that cause contamination with different trichothecene mycotoxins. The molecular mechanisms behind Fusarium resistance in oat have yet to be elucidated. In the present work, we identified and characterised two oat UDP-glucosyltransferases orthologous to barley HvUGT13248. Overexpression of the latter in wheat had been shown previously to increase resistance to deoxynivalenol (DON) and nivalenol (NIV) and to decrease disease the severity of both Fusarium head blight and Fusarium crown rot. Both oat genes are highly inducible by the application of DON and during infection with . Heterologous expression of these genes in a toxin-sensitive strain of conferred high levels of resistance to DON, NIV and HT-2 toxins, but not C4-acetylated trichothecenes (T-2, diacetoxyscirpenol). Recombinant enzymes AsUGT1 and AsUGT2 expressed in rapidly lost activity upon purification, but the treatment of whole cells with the toxin clearly demonstrated the ability to convert DON into DON-3-O-glucoside. The two UGTs could therefore play an important role in counteracting the Fusarium virulence factor DON in oat.
Topics: Avena; Fusarium; Glucosyltransferases; Mycotoxins; Plant Proteins; Trichothecenes; Uridine Diphosphate
PubMed: 35878183
DOI: 10.3390/toxins14070446 -
Foods (Basel, Switzerland) May 2022To monitor the contamination of a type A trichothecene, diacetoxyscirpenol (DAS), one monoclonal antibody (mAb) 8A9 with high affinity and specificity was prepared in...
To monitor the contamination of a type A trichothecene, diacetoxyscirpenol (DAS), one monoclonal antibody (mAb) 8A9 with high affinity and specificity was prepared in the present study. The mAb 8A9 showed a 50% inhibition concentration (IC) of 0.31 μg/L, which is of the highest affinity reported to date. An indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) and lateral flow immunoassay (LFIA) based on mAb 8A9 were developed and exhibited limits of detection as low as 0.65 μg/kg and 100 μg/kg in rice samples, respectively. The molecular recognition mechanism of mAb 8A9 to DAS was explored by molecular docking. The results showed that the hydrophobic amino acids of mAb 8A9 interacted with DAS by forming hydrogen bonds and a pi-sigma bond, which lead to a highly specific recognition of DAS. In summary, we produced one mAb, developed ELISA and LFIA for DAS detection in rice with significantly sensitivity, specificity, accuracy, and precision.
PubMed: 35681298
DOI: 10.3390/foods11111548 -
Molecules (Basel, Switzerland) Jan 2021Trichothecene mycotoxins are sesquiterpenoid compounds primarily produced by fungi in taxonomical genera such as , , , and others, under specific climatic conditions on... (Review)
Review
Trichothecene mycotoxins are sesquiterpenoid compounds primarily produced by fungi in taxonomical genera such as , , , and others, under specific climatic conditions on a worldwide basis. mold is a major plant pathogen and produces a number of trichothecene mycotoxins including deoxynivalenol (or vomitoxin), nivalenol, diacetoxyscirpenol, and T-2 toxin, HT-2 toxin. Monogastrics are sensitive to vomitoxin, while poultry and ruminants appear to be less sensitive to some trichothecenes through microbial metabolism of trichothecenes in the gastrointestinal tract. Trichothecene mycotoxins occur worldwide however both total concentrations and the particular mix of toxins present vary with environmental conditions. Proper agricultural practices such as avoiding late harvests, removing overwintered stubble from fields, and avoiding a corn/wheat rotation that favors growth in residue can reduce trichothecene contamination of grains. Due to the vague nature of toxic effects attributed to low concentrations of trichothecenes, a solid link between low level exposure and a specific trichothecene is difficult to establish. Multiple factors, such as nutrition, management, and environmental conditions impact animal health and need to be evaluated with the knowledge of the mycotoxin and concentrations known to cause adverse health effects. Future research evaluating the impact of low-level exposure on livestock may clarify the potential impact on immunity. Trichothecenes are rapidly excreted from animals, and residues in edible tissues, milk, or eggs are likely negligible. In chronic exposures to trichothecenes, once the contaminated feed is removed and exposure stopped, animals generally have an excellent prognosis for recovery. This review shows the occurrence of trichothecenes in food and feed in 2011-2020 and their toxic effects and provides a summary of the discussions on the potential public health concerns specifically related to trichothecenes residues in foods associated with the exposure of farm animals to mycotoxin-contaminated feeds and impact to human health. Moreover, the article discusses the methods of their detection.
Topics: Animal Feed; Animals; Food Analysis; Food Contamination; Food Microbiology; Foodborne Diseases; Humans; Mitosporic Fungi; Trichothecenes
PubMed: 33467103
DOI: 10.3390/molecules26020454 -
Risk to human and animal health related to the presence of 4,15-diacetoxyscirpenol in food and feed.EFSA Journal. European Food Safety... Aug 20184,15-Diacetoxyscirpenol (DAS) is a mycotoxin primarily produced by fungi and occurring predominantly in cereal grains. As requested by the European Commission, the EFSA...
4,15-Diacetoxyscirpenol (DAS) is a mycotoxin primarily produced by fungi and occurring predominantly in cereal grains. As requested by the European Commission, the EFSA Panel on Contaminants in the Food Chain (CONTAM) assessed the risk of DAS to human and animal health related to its presence in food and feed. Very limited information was available on toxicity and on toxicokinetics in experimental and farm animals. Due to the limitations in the available data set, human acute and chronic health-based guidance values (HBGV) were established based on data obtained in clinical trials of DAS as an anticancer agent (anguidine) after intravenous administration to cancer patients. The CONTAM Panel considered these data as informative for the hazard characterisation of DAS after oral exposure. The main adverse effects after acute and repeated exposure were emesis, with a no-observed-adverse-effect level (NOAEL) of 32 μg DAS/kg body weight (bw), and haematotoxicity, with a NOAEL of 65 μg DAS/kg bw, respectively. An acute reference dose (ARfD) of 3.2 μg DAS/kg bw and a tolerable daily intake (TDI) of 0.65 μg DAS/kg bw were established. Based on over 15,000 occurrence data, the highest acute and chronic dietary exposures were estimated to be 0.8 and 0.49 μg DAS/kg bw per day, respectively, and were not of health concern for humans. The limited information for poultry, pigs and dogs indicated a low risk for these animals at the estimated DAS exposure levels under current feeding practices, with the possible exception of fattening chicken. Assuming similar or lower sensitivity than for poultry, the risk was considered overall low for other farm and companion animal species for which no toxicity data were available. In consideration of the similarities of several trichothecenes and the likelihood of co-exposure via food and feed, it could be appropriate to perform a cumulative risk assessment for this group of substances.
PubMed: 32626015
DOI: 10.2903/j.efsa.2018.5367 -
Toxins Jun 2020The trichothecene mycotoxins contaminate cereal grains and have been related to alimentary toxicosis resulted in emetic response. This family of mycotoxins comprises...
The trichothecene mycotoxins contaminate cereal grains and have been related to alimentary toxicosis resulted in emetic response. This family of mycotoxins comprises type A to D groups of toxic sesquiterpene chemicals. Diacetoxyscirpenol (DAS), one of the most toxic type A trichothecenes, is considered to be a potential risk for human and animal health by the European Food Safety Authority. Other type A trichothecenes, T-2 toxin and HT-2 toxin, as well as type B trichothecene deoxynivalenol (DON), have been previously demonstrated to induce emetic response in the mink, and this response has been associated with the plasma elevation of neurotransmitters peptide YY (PYY) and serotonin (5-hydroxytryptamine, 5-HT). However, it is found that not all the type A and type B trichothecenes have the capacity to induce PYY and 5-HT. It is necessary to identify the roles of these two emetogenic mediators on DAS-induced emesis. The goal of this study was to determine the emetic effect of DAS and relate this effect to PYY and 5-HT, using a mink bioassay. Briefly, minks were fasted one day before experiment and given DAS by intraperitoneally and orally dosing on the experiment day. Then, emetic episodes were calculated and blood collection was employed for PYY and 5-HT test. DAS elicited robust emetic responses that corresponded to upraised PYY and 5-HT. Blocking the neuropeptide Y2 receptor (NPY2R) diminished emesis induction by PYY and DAS. The serotonin 3 receptor (5-HT3R) inhibitor granisetron totally restrained the induction of emesis by serotonin and DAS. In conclusion, our findings demonstrate that PYY and 5-HT have critical roles in DAS-induced emetic response.
Topics: Animals; Antiemetics; Disease Models, Animal; Female; Granisetron; Mink; Peptide YY; Receptors, Gastrointestinal Hormone; Receptors, Serotonin, 5-HT3; Secretory Pathway; Serotonin; Serotonin 5-HT3 Receptor Antagonists; Trichothecenes; Up-Regulation; Vomiting
PubMed: 32630472
DOI: 10.3390/toxins12060419 -
Medicinal Research Reviews Sep 2015Although fungi produce highly structurally diverse metabolites, many of which have served as excellent sources of pharmaceuticals, no fungi-derived agent has been... (Review)
Review
Although fungi produce highly structurally diverse metabolites, many of which have served as excellent sources of pharmaceuticals, no fungi-derived agent has been approved as a cancer drug so far. This is despite a tremendous amount of research being aimed at the identification of fungal metabolites with promising anticancer activities. This review discusses the results of clinical testing of fungal metabolites and their synthetic derivatives, with the goal to evaluate how far we are from an approved cancer drug of fungal origin. Also, because in vivo studies in animal models are predictive of the efficacy and toxicity of a given compound in a clinical situation, literature describing animal cancer testing of compounds of fungal origin is reviewed as well. Agents showing the potential to advance to clinical trials are also identified. Finally, the technological challenges involved in the exploitation of fungal biodiversity and procurement of sufficient quantities of clinical candidates are discussed, and potential solutions that could be pursued by researchers are highlighted.
Topics: Androstadienes; Animals; Antineoplastic Agents; Aphidicolin; Biological Products; Clinical Trials as Topic; Cyclohexanes; Diketopiperazines; Disease Models, Animal; Drug Design; Drug Resistance, Neoplasm; Fatty Acids, Unsaturated; Female; Fungi; Humans; Macrolides; Male; Mice; Neoplasms; Polycyclic Sesquiterpenes; Sesquiterpenes; Trichothecenes; Wortmannin
PubMed: 25850821
DOI: 10.1002/med.21348 -
Toxins Apr 2018Trichothecene mycotoxins are common contaminants in cereal grains and negatively impact human and animal health. Although anorexia is a common hallmark of type B... (Comparative Study)
Comparative Study
Trichothecene mycotoxins are common contaminants in cereal grains and negatively impact human and animal health. Although anorexia is a common hallmark of type B trichothecenes-induced toxicity, less is known about the anorectic potencies of type A trichothecenes. The purpose of this study was to compare the anorectic potencies of four type A trichothecenes (T-2 toxin (T-2), HT-2 toxin (HT-2), diacetoxyscirpenol (DAS), and neosolaniol (NEO)) in mice. Following oral exposure to T-2, HT-2, DAS, and NEO, the no observed adverse effect levels (NOAELs) and lowest observed adverse effect levels (LOAELs) were 0.01, 0.01, 0.1, and 0.01 mg/kg body weight (BW), and 0.1, 0.1, 0.5, and 0.1 mg/kg BW, respectively. Following intraperitoneal (IP) exposure to T-2, HT-2, DAS, and NEO, the NOAELs were 0.01 mg/kg BW, except for DAS (less than 0.01 mg/kg BW), and the LOAELs were 0.1, 0.1, 0.01, and 0.1 mg/kg BW, respectively. Taken together, the results suggest that (1) type A trichothecenes could dose-dependently elicit anorectic responses following both oral gavage and IP exposure in mice; (2) the anorectic responses follow an approximate rank order of T-2 = HT-2 = NEO > DAS for oral exposure, and DAS > T-2 = HT-2 = NEO for IP administration; (3) IP exposure to T-2, HT-2, DAS, and NEO evoked stronger anorectic effects than oral exposure. From a public health perspective, comparative anorectic potency data should be useful for establishing toxic equivalency factors for type A trichothecenes.
Topics: Animals; Anorexia; Appetite Depressants; Dose-Response Relationship, Drug; Female; Mice; No-Observed-Adverse-Effect Level; Trichothecenes
PubMed: 29710820
DOI: 10.3390/toxins10050179 -
Poultry Science Mar 1994The effects of feeding 2 mg ochratoxin A (OA) and 6 mg 4,15-diacetoxyscirpenol (DAS)/kg of diet singly and in combination were characterized in male broiler chicks from...
The effects of feeding 2 mg ochratoxin A (OA) and 6 mg 4,15-diacetoxyscirpenol (DAS)/kg of diet singly and in combination were characterized in male broiler chicks from 1 to 19 d of age. Body weights were depressed by OA, DAS, and the OA-DAS combination. There was a significant antagonistic interaction between OA and DAS for uric acid and cholesterol. The efficiency of feed utilization was reduced by DAS alone and by the OA-DAS combination. When compared with controls, additive toxicity was exhibited for reduced efficiency of feed utilization, increased relative weights of the liver and gizzard, and decreased concentration of serum total protein, mean corpuscular volume, and mean corpuscular hemoglobin. All chicks were scored for oral lesions using a scale of 1 to 4 (0 = no visible lesions; 3 = severe lesions). Oral lesions (average score = 2.6) were present in over 90% of the chicks receiving the DAS diet with or without OA. These data demonstrate that both OA and DAS alone and the OA-DAS combination can adversely affect broiler performance and health.
Topics: Animal Feed; Animals; Body Weight; Chickens; Drug Interactions; Eating; Male; Ochratoxins; Organ Size; Trichothecenes
PubMed: 8177819
DOI: 10.3382/ps.0730408