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DepA, a pyrroloquinoline quinone (PQQ)-dependent enzyme isolated from Devosia mutans 17-2-E-8, exhibits versatility in oxidizing deoxynivalenol (DON) and its derivatives. This study explored DepA's substrate specificity and enzyme kinetics, focusing on DON and 15-acetyl-DON. Besides efficiently oxidizing DON, DepA also transforms 15-acetyl-DON into 15-acetyl-3-keto-DON, as identified via LC-MS/MS and NMR analysis. The kinetic parameters, including the maximum reaction rate, turnover number, and catalytic efficiency, were thoroughly evaluated. DepA-PQQ complex docking was deployed to rationalize the substrate specificity of DepA. This study further delves into the reduced toxicity of the transformation products, as demonstrated via enzyme homology modeling and in silico docking analysis with yeast 80S ribosomes, indicating a potential decrease in toxicity due to lower binding affinity. Utilizing the response surface methodology and central composite rotational design, mathematical models were developed to elucidate the relationship between the enzyme and cofactor concentrations, guiding the future development of detoxification systems for liquid feeds and grain processing. This comprehensive analysis underscores DepA's potential for use in mycotoxin detoxification, offering insights for future applications.

In order to alleviate the toxic effects of aflatoxins B1 (AFB1) on inflammatory responses in the intestine, liver, and kidney of broilers, the aflatoxin B1-degrading enzyme, montmorillonite, and compound probiotics were selected and combined to make a triple-action compound mycotoxin detoxifier (CMD). The feeding experiment was divided into two stages. In the early feeding stage (1−21 day), a total of 200 one-day-old Ross broilers were randomly divided into four groups; in the later feeding stage (22−42 day), 160 broilers aged at 22 days were assigned to four groups: Group A: basal diet (4.31 μg/kg AFB1); Group B: basal diet with 40 μg/kg AFB1; Group C: Group A plus 1.5 g/kg CMD; Group D: Group B plus 1.5 g/kg CMD. After the feeding experiment, the intestine, liver, and kidney tissues of the broilers were selected to investigate the molecular mechanism for CMD to alleviate the tissue damages. Analyses of mRNA abundances and western blotting (WB) of inflammatory factors, as well as immunohistochemical (IHC) staining of intestine, liver, and kidney tissues showed that AFB1 aggravated the inflammatory responses through NF-κB and TN-α signaling pathways via TLR pattern receptors, while the addition of CMD significantly inhibited the inflammatory responses. Phylogenetic investigation showed that AFB1 significantly increased interleukin-1 receptor-associated kinase (IRAK-1) and mitogen-activated protein kinase (MAPK) activities (p < 0.05), which were restored to normal levels by CMD addition, indicating that CMD could alleviate cell inflammatory damages induced by AFB1.

Deoxynivalenol (DON) is a mycotoxin, produced by filamentous fungi such as Fusarium graminearum, that causes significant yield losses of cereal grain crops worldwide. One of the most promising methods to detoxify this mycotoxin involves its enzymatic epimerization to 3-epi-DON. DepB plays a critical role in this process by reducing 3-keto-DON, an intermediate in the epimerization process, to 3-epi-DON. DepB Rleg from Rhizobium leguminosarum is a member of the new aldo-keto reductase family, AKR18, and it has the unusual ability to utilize both NADH and NADPH as coenzymes, albeit with a 40-fold higher catalytic efficiency with NADPH compared to NADH. Structural analysis of DepB Rleg revealed the putative roles of Lys-217, Arg-290, and Gln-294 in NADPH specificity. Replacement of these residues by site-specific mutagenesis to negatively charged amino acids compromised NADPH binding with minimal effects on NADH binding. The substrate-binding site of DepB Rleg is larger than its closest structural homolog, AKR6A2, likely contributing to its ability to utilize a wide range of aldehydes and ketones, including the mycotoxin, patulin, as substrates. The structure of DepB Rleg also suggests that 3-keto-DON can adopt two binding modes to facilitate 4-pro-R hydride transfer to either the re- or si-face of the C3 ketone providing a possible explanation for the enzyme's ability to convert 3-keto-DON to 3-epi-DON and DON in diastereomeric ratios of 67.2% and 32.8% respectively., (© 2022. The Author(s).)

Deoxynivalenol, a mycotoxin that may present in almost all cereal products, can cause huge economic losses in the agriculture industry and seriously endanger food safety and human health. Microbial detoxifications using microbial consortia may provide a safe and effective strategy for DON mitigation. In order to study the interactions involving DON degradation and change in microbial flora, four samples from different natural niches, including a chicken stable (expJ), a sheep stable (expY), a wheat field (expT) and a horse stable (expM) were collected and reacted with purified DON. After being co-incubated at 30 °C with 130 rpm shaking for 96 h, DON was reduced by 74.5%, 43.0%, 46.7%, and 86.0% by expJ, expY, expT, and expM, respectively. After DON (0.8 mL of 100 μg/mL) was co-cultivated with 0.2 mL of the supernatant of each sample (i.e., suspensions of microbial communities) at 30 °C for 96 h, DON was reduced by 98.9%, 99.8%, 79.5%, and 78.9% in expJ, expY, expT, and expM, respectively, and was completely degraded after 8 days by all samples except of expM. DON was confirmed being transformed into de-epoxy DON (DOM-1) by the microbial community of expM. The bacterial flora of the samples was compared through 16S rDNA flux sequencing pre- and post the addition of DON. The results indicated that the diversities of bacterial flora were affected by DON. After DON treatment, the most abundant bacteria belong to Galbibacter (16.1%) and Pedobacter (8.2%) in expJ; Flavobacterium (5.9%) and Pedobacter (5.5%) in expY; f&#95;Microscillaceae (13.5%), B1-7BS (13.4%), and RB41 (10.5%) in expT; and Acinetobacter (24.1%), Massilia (8.8%), and Arthrobacter (7.6%) in expM. This first study on the interactions between DON and natural microbial flora provides useful information and a methodology for further development of microbial consortia for mycotoxin detoxifications.

Trichothecenes are the most prevalent mycotoxins contaminating cereal grains. Some of them are also considered as the virulence factors of Fusarium head blight disease. However, the mechanism behind the structure-activity relationship for trichothecenes remains unexplained. Filling this information gap is a crucial step for developing strategies to manage this large family of mycotoxins in food and feed. Here, we perform an in-depth re-examination of the existing structures of Saccharomyces cerevisiae ribosome complexed with three different trichothecenes. Multiple binding interactions between trichothecenes and 25S rRNA, including hydrogen bonds, nonpolar pi stacking interactions and metal ion coordination interactions, are identified as important binding determinants. These interactions are mainly contributed by the key structural elements to the toxicity of trichothecenes, including the oxygen in the 12,13-epoxide ring and a double bond between C 9 and C 10 . In addition, the C 3 -OH group also participates in binding. The comparison of three trichothecenes binding to the ribosome, along with their binding pocket architecture, suggests that the substitutions at different positions impact trichothecenes binding in two different patterns. Moreover, the binding of trichothecenes induced conformation changes of several nucleotide bases in 25S rRNA. This then provides a structural framework for understanding the structure-activity relationships apparent in trichothecenes. This study will facilitate the development of strategies aimed at detoxifying mycotoxins in food and feed and at improving the resistance of cereal crops to Fusarium fungal diseases.

Fungal disease of grain crops is a concern for the agricultural industry, resulting in economic losses. Aside from severe yield losses, mycotoxigenic fungi such as Penicillium and Fusarium can produce harmful mycotoxins, including deoxynivalenol (DON), zearalenone (ZEN), and ochratoxin A (OTA). This proof-of-concept study explored the feasibility and effects of ultraviolet (UV) C light at 253.7 nm to reduce fungal and mycotoxin loads on model surfaces as well as on maize and wheat kernels using benchtop 2D and 3D illumination strategies. Reduction of Penicillium verrucosum (98.6%) and Fusarium graminearum (88.8%) on agar was achieved using a UV-C dose of 100 mJ cm -2 . Naturally occurring fungal growth resembling P. verrucosum on maize was reduced by 79% after exposure to 5000 mJ cm -2 . Similarly, fungal growth resembling F. graminearum on maize was reduced by 60% with 1000 mJ cm -2 . On wheat, significant reduction of fungal growth was not observed. Maximal reduction of DON (97.3%), ZEN (75.4%), and OTA (91.2%) on filter paper was obtained using 15,000 mJ cm -2 . The overall reduction of DON (30%; 14%), ZEN (52%; 42%), and OTA (17%; 6%) on maize and wheat, respectively, was lower than on filter paper. Moisture and crude protein content as well as percent germination of maize kernels were not affected by UV-C treatment up to 5000 mJ cm -2 . This study has shown that 3D UV-C treatment is a feasible option for reducing Fusarium and Penicillium growth on maize kernels and, at higher doses, decreasing ZEN by ~ 50%.

Deoxynivalenol (DON) is a type B trichothecene mycotoxin that is commonly detected in grains infested with Fusarium species. The maximum tolerated levels of DON in the majority of world's countries are restricted to 0.75 mg kg -1 within the human food chain and to less than 1-5 mg kg -1 in animal feed depending on the feed material and/or animal species due to DON's short and long-term adverse effects on human health and animal productivity. The ability to accurately analyze DON and some of its fungal/bacterial metabolites is increasingly gaining a paramount importance in food/feed analysis and research. In this study, we used the immuno-affinity approach to enrich and detect DON and three of its bacterial metabolites, namely 3-epi-DON, 3-keto-DON, and deepoxy-DON (DOM-1). The optimized enrichment step coupled with high performance liquid chromatography can accurately and reproducibly quantify the aforementioned metabolites in feed matrixes (silage extract as an example in this case). It minimizes any background interface and provides a fast and easy-to-operate protocol for the analytical determination of such metabolites. More importantly, the presented data demonstrates the ability of the utilized monoclonal antibody, generated originally to capture DON in Enzyme-Linked Immunosorbent Assays (ELISA), to cross react with three less/non-toxic DON metabolites. This raises the concerns about the genuine need to account for such cross-reactivity when DON contamination is assessed through an immuno-affinity based analyses using the investigated antibody., (Crown Copyright © 2018. Published by Elsevier B.V. All rights reserved.)

Mycotoxins are secondary fungal metabolites associated with adverse human health and animal productivity consequences.[...]., Competing Interests: The authors declare no conflict of interest.

Mycotoxins, the secondary metabolites of mycotoxigenic fungi, have been found in almost all agricultural commodities worldwide, causing enormous economic losses in livestock production and severe human health problems. Compared to traditional physical adsorption and chemical reactions, interest in biological detoxification methods that are environmentally sound, safe and highly efficient has seen a significant increase in recent years. However, researchers in this field have been facing tremendous unexpected challenges and are eager to find solutions. This review summarizes and assesses the research strategies and methodologies in each phase of the development of microbiological solutions for mycotoxin mitigation. These include screening of functional microbial consortia from natural samples, isolation and identification of single colonies with biotransformation activity, investigation of the physiological characteristics of isolated strains, identification and assessment of the toxicities of biotransformation products, purification of functional enzymes and the application of mycotoxin decontamination to feed/food production. A full understanding and appropriate application of this tool box should be helpful towards the development of novel microbiological solutions on mycotoxin detoxification.

Background: Contamination of agricultural commodities with multiple trichothecene mycotoxins, produced by toxigenic Fusarium species, is a food safety issue, which greatly affects grain production and marketing worldwide. Importantly, exposure to multiple trichothecenes may increase toxicity in animals due to their synergistic and/or additive effects. To address the problem this study aimed to achieve a novel biological trait capable of detoxifying various food and feed contaminating trichothecenes under aerobic and anaerobic conditions and wide range of temperatures., Results: A highly enriched microbial consortium (called DX100) capable of transforming eleven trichothecenes to significantly less toxic de-epoxy forms was achieved after prolonged incubation of soil microbial culture with 200 μg/mL deoxynivalenol (DON). DX100 demonstrated de-epoxidation activity under aerobic and anaerobic conditions, a greater range of temperatures and around neutral pH. The consortium contains 70% known and 30% unknown bacterial species, dominated by Stenotrophomonas species. Probably novel bacteria including strains of Stenotrophomonas and Alkaliphilus-Blautia species complex could be involved in aerobic and anaerobic de-epoxidation of trichothecenes, respectively. DX100 showed rapid and stable activity by de-epoxidizing 100% of 50 μg/mL deoxynivalenol at 48 h of incubation and retaining de-epoxidation ability after 100 subcultures in mineral salts broth (MSB). It was able to de-epoxidize high concentration of DON (500 μg/mL), and transformed ten more food contaminating trichothecenes into de-epoxy forms and/or other known/unknown compounds. Microbial de-epoxidation rate increased with increasing trichothecene concentrations in the broth media, suggesting that DX100 maintains a robust trichothecene detoxifying mechanism. Furthermore, the nature of microbial de-epoxidation reaction and inhibition of the reaction by sodium azide and the finding that bacterial cell culture lysate retained activity suggests that certain cytoplasmic reductases may be responsible for the de-epoxidation activity., Conclusions: This study reports the enrichment procedure for obtaining an effective and stable microbial consortium DX100 capable of de-epoxidizing several food contaminating trichothecene mycotoxins. DX100, which has de-epoxidation ability under wide range of conditions, represents a unique enzymatic source which has great industrial potential for reducing contamination of foods/feeds with multiple trichothecenes, and minimizing their synergistic/additive cytotoxic effects on consumer health.

Background: Contamination of grains with trichothecene mycotoxins, especially deoxynivalenol (DON), has been an ongoing problem for Canada and many other countries. Mycotoxin contamination creates food safety risks, reduces grain market values, threatens livestock industries, and limits agricultural produce exports. DON is a secondary metabolite produced by some Fusarium species of fungi. To date, there is a lack of effective and economical methods to significantly reduce the levels of trichothecene mycotoxins in food and feed, including the efforts to breed Fusarium pathogen-resistant crops and chemical/physical treatments to remove the mycotoxins. Biological approaches, such as the use of microorganisms to convert the toxins to non- or less toxic compounds, have become a preferred choice recently due to their high specificity, efficacy, and environmental soundness. However, such approaches are often limited by the availability of microbial agents with the ability to detoxify the mycotoxins. In the present study, an approach with PCR-DGGE guided microbial selection was developed and used to isolate DON -transforming bacteria from chicken intestines, which resulted in the successful isolation of several bacterial isolates that demonstrated the function to transform DON to its de-epoxy form, deepoxy-4-deoxynivalenol (DOM-1), a product much less toxic than DON., Results: The use of conventional microbiological selection strategies guided by PCR-DGGE (denaturing gradient gel electrophoresis) bacterial profiles for isolating DON-transforming bacteria has significantly increased the efficiency of the bacterial selection. Ten isolates were identified and isolated from chicken intestines. They were all able to transform DON to DOM-1. Most isolates were potent in transforming DON and the activity was stable during subculturing. Sequence data of partial 16S rRNA genes indicate that the ten isolates belong to four different bacterial groups, Clostridiales, Anaerofilum, Collinsella, and Bacillus., Conclusions: The approach with PCR-DGGE guided microbial selection was effective in isolating DON-transforming bacteria and the obtained bacterial isolates were able to transform DON.

Mycotoxins are found worldwide in cereal grains, animal feed and human food that are produced from contaminated grains. This presents food safety risks. A variety of methods has been developed to reduce the safety risks by removing mycotoxins from contaminated grain products, eliminate the bioavailability of mycotoxins in the gastrointestinal system, degrade mycotoxins in food and feed, reduce mycotoxins pre- and post-harvest, and prevent (mycotoxin involved) plant disease. These techniques include physical methods such as flotation, extraction and adsorption, chemical reactions such as alkalization, oxidation, heat and irradiation, as well as biological detoxifications using microorganisms, enzymes and resistant plants. Most of the recent patented techniques for detoxification of mycotoxins in feeds and food matrices are discussed for an improved understanding of the patent techniques and insights into detoxification of mycotoxins.

Deoxynivalenol (DON) is a widespread mycotoxin that affects the intestinal health of animals and humans. In the present study, we performed RNA-sequencing and 16S rRNA sequencing in piglets after DON and glycyrrhizic acid and compound probiotics (GAP) supplementation to determine the changes in intestinal transcriptome and microbiota. Transcriptome results indicated that DON exposure altered intestinal gene expression involved in nutrient transport and metabolism. Genes related to lipid metabolism, such as PLIN1, PLIN4, ADIPOQ, and FABP4 in the intestine, were significantly decreased by DON exposure, while their expressions were significantly increased after GAP supplementation. KEGG enrichment analysis showed that GAP supplementation promoted intestinal digestion and absorption of proteins, fats, vitamins, and other nutrients. Results of gut microbiota composition showed that GAP supplementation significantly improved the diversity of gut microbiota. DON exposure significantly increased Proteobacteria, Actinobacteria, and Bacillus abundances and decreased Firmicutes, Lactobacillus, and Streptococcus abundances; however, dietary supplementation with GAP observably recovered their abundances to normal. In addition, predictive functions by PICRUSt analysis showed that DON exposure decreased lipid metabolism, whereas GAP supplementation increased immune system. This result demonstrated that dietary exposure to DON altered the intestinal gene expressions related to nutrient metabolism and induced disturbances of intestinal microbiota, while supplementing GAP to DON-contaminated diets could improve intestinal health for piglets. [ABSTRACT FROM AUTHOR]

Application of ultraviolet (UV) irradiation for the degradation of chemical contaminants in food products has gained more and more interest in the past two decades. The majority of the research in this field was on mycotoxins, especially aflatoxins and patulin, with limited studies on pesticide residues and other chemical contaminants in food. These studies have been focused on identifying the structure and toxicity of degradation products, investigating the influence of UV treatment factors on the degradation efficiency, determining the impact of UV treatment on the quality of food products, and developing updated UV treatment methods such as TiO2 induced photocatalytic degradation. The summary of published literatures provided insights into future research opportunities in this area, which include determining a standard for the UV treatment description, working with naturally contaminated samples rather than artificially spiked samples, conducting pilot plant or industrial scale studies, examining more targets and conducting multi‐targets studies, and developing more innovative methods for UV treatment. [ABSTRACT FROM AUTHOR]

Deoxynivalenol (DON) is a major fusarium toxin widely detected in cereal grains. The inadvertent exposure to this fungal secondary-metabolite gives rise to a myriad of adverse health effects including appetite loss, emesis, and suppression of the immune system. While most of the attention this mycotoxin has gained in the past four decades was related to its eukaryotic toxicity (monogastric animals and plants more precisely), recent studies have begun to reveal its negative influence on prokaryotes. Recently presented evidence indicates that DON can negatively affect many bacterial species, raising the possibility of DON-induced imbalances within the microbiota of the human and animal gut, in addition to other environmental niches. This in turn has led to a greater interest in understanding bacterial responses toward DON, and the involved mechanism(s) and metabolic pathways, in order to build a more comprehensive picture of DON-induced changes in both prokaryotes and eukaryotes alike. This study reveals the transcriptomic profiling of Devosia mutans strain 17-2-E-8 after the inclusion of DON within its growth medium. The results highlight three adaptive mechanisms involved in the response of D. mutans 17-2-E-8 to this mycotoxin, which include: (a) activation of adenosine 5'-triphosphate-binding cassette transporters; (b) engagement of a toxin-specific pyrroloquinoline quinone-dependent detoxification pathway; and finally (c) the upregulation of auxiliary coping proteins such as porins, glutathione S-transferases, and phosphotransferases. Some of the identified mechanisms are universal in nature and are shared with other bacterial genera and species. [ABSTRACT FROM AUTHOR]

Penicillium expansum is a destructive phytopathogen provoking the blue mold decay of pome fruits and producing a polyketide-derived mycotoxin, patulin. In this study, the effects of exogenous essential oil decanal on development and patulin production of P. expansum were determined. Results indicated that 0.12 g L −1 decanal could significantly inhibit the growth of P. expansum in vitro . 0.24 g L −1 decanal showed a good controlling effect against the blue mold rot on apple and pear fruit. Besides, decanal could inhibit patulin production and the expression of genes involved in patulin biosynthesis. Through RNA sequencing approach, 1703, 3247 and 3963 genes were found which have changed abundantly after 6 h, 12 h and 18 h of incubation in decanal treated samples. Differentially expressed genes (DEGs) mainly participated in metabolism and genetic information processing. The expressions of about two-thirds of the DEGs were down-regulated. Among them, DEGs involved in oxidative phosphorylation, transcription, and translation would be partly responsible for growth inhibition of P. expansum . The findings would provide some new insights for exploring the possible antifungal mechanisms of decanal against P. expansum . [ABSTRACT FROM AUTHOR]

Summary: The biological detoxification of mycotoxins, including deoxynivalenol (DON), represents a very promising approach to address the challenging problem of cereal grain contamination. The recent discovery of Devosia mutans 17‐2‐E‐8 (Devosia spp. 17‐2‐E‐8), a bacterial isolate capable of transforming DON to the non‐toxic stereoisomer 3‐epi‐deoxynivalenol, along with earlier reports of bacterial species capable of oxidizing DON to 3‐keto‐DON, has generated interest in the possible mechanism and enzyme(s) involved. An understanding of these details could pave the way for novel strategies to manage this widely present toxin. It was previously shown that DON epimerization proceeds through a two‐step biocatalysis. Significantly, this report describes the identification of the first enzymatic step in this pathway. The enzyme, a dehydrogenase responsible for the selective oxidation of DON at the C3 position, was shown to readily convert DON to 3‐keto‐DON, a less toxic intermediate in the DON epimerization pathway. Furthermore, this study provides insights into the PQQ dependence of the enzyme. This enzyme may be part of a feasible strategy for DON mitigation within the near future. This report describes the discovery of a dehydrogenase responsible for the selective oxidation of mycotoxin deoxynivalenol (DON) at the C3 position. The enzyme was shown to readily convert DON to 3‐keto‐DON, a less toxic intermediate in the DON epimerization pathway. This enzyme may be part of a feasible strategy for DON mitigation within the near future. [ABSTRACT FROM AUTHOR]

The yeast strain, Saccharomyces cerevisiae YE-7, was tested to control the apple blue mold disease caused by Penicillium expansum and the accumulation of patulin mycotoxin. Compared with control, pre-treatment of pathogen-infected apples with YE-7 significantly reduced the incidence of blue mold diseases and patulin accumulation in rotten apple tissue by 48% and 42.6%, respectively. Interestingly, late treatment of pathogen-infected apples with YE-7 did not decrease patulin accumulation in the rotten tissue compared with pre-treatment or simultaneous-treatment. Independently, patulin amount and gene expression of isoepoxydon dehydrogenase were also measured. YE-7 pre-treated apples showed 75% and four times reduction in patulin accumulation and IDH gene expression, respectively. The results indicated that YE-7 directly affected patulin biosynthesis and did not affect accumulated patulin. On the other hand, cold storage enhanced the effect of YE-7 on apple blue mold disease incidence. Practical applications Postharvest blue mold decay caused by Penicillium expansum was important postharvest disease of apples. In addition, under favorable conditions, P. expansum can cause severe losses in apple fruits due to the production of patulin. In this study, a strain of S. cerevisiae (YE-7) was assessed for its efficacy not only in controlling apple blue mold diseases, but also in reducing patulin accumulation in fruit tissue. The research will give a practical way to control the decay in a bio-control way instead of the chemical. [ABSTRACT FROM AUTHOR]

Patulin is the main mycotoxin contaminating apples. During the brewing of alcoholic beverages, this mycotoxin is degraded to ascladiol, which is also the last precursor of patulin. The present study aims (1) to characterize the last step of the patulin biosynthetic pathway and (2) to describe the toxicity of ascladiol. A patE deletion mutant was generated in Penicillium expansum. In contrast to the wild strain, this mutant does not produce patulin but accumulates high levels of E-ascladiol with few traces of Z-ascladiol. This confirms that patE encodes the patulin synthase involved in the conversion of E-ascladiol to patulin. After purification, cytotoxicities of patulin and E- and Z-ascladiol were investigated on human cell lines from liver, kidney, intestine, and immune system. Patulin was cytotoxic for these four cell lines in a dose-dependent manner. By contrast, both E- and Z-ascladiol were devoid of cytotoxicity. Microarray analyses on human intestinal cells treated with patulin and E-ascladiol showed that the latter, unlike patulin, did not alter the whole human transcription. These results demonstrate that E- and Z-ascladiol are not toxic and therefore patulin detoxification strategies leading to the accumulation of ascladiol are good approaches to limit the patulin risk. [ABSTRACT FROM AUTHOR]

The degradation of patulin introduced into different juices then treated with high hydrostatic pressure (HHP) was evaluated. A model juice prepared from apple and spinach (AS) was studied along with commercially available apple-based beverages; Pineapple:Apple:Mint (PAM), Apple:Carrot:Beet:Lemon:Ginger (CAB) and Romaine:Celery:Cucumber:Apple:Spinach:Kale, Parsley:lemon (GJ). The extent of patulin degradation was found to be dependent on applied pressure and processing time (degradation rates ranged from 0.04 to 0.19 ppb/s). The extent of patulin degradation could also be significantly (P < 0.05) correlated with the sulfhydryl group concentration of the juice with ascorbic acid and nitrite being less significant. HHP treatment of 600 MPa for 300 s at 11 °C resulted in a 62 ppb decrease in patulin introduced into GJ juice which also contained the highest level of thiols (97 μM). The thiol concentration of the other juices ranged between 39 and 69 μM with a corresponding decrease in patulin of 43–49 ppb following the same HHP treatment. The study has illustrated that HHP can be applied as a risk management tool to control patulin in apple based beverages although the extent of mycotoxin degradation is dependent on processing conditions and composition of the juice. [ABSTRACT FROM AUTHOR]

Sourdough starter cultures are rich sources of endogenous lactic acid bacteria. The extended shelf lives of sourdough breads are attributed to a large array of organic acids and low-molecular-weight metabolites produced during the fermentation process. Different species belonging to the lactic acid bacteria group of microorganisms, mainly Lactobacillus and Leuconostoc, are increasingly gaining the attention as possible means for inhibiting mold growth in animal feed and human food chains. In addition, certain lactic acid bacteria strains isolated from sourdough starters were also shown to reduce mycotoxins concentrations in contaminated products either by binding or degradation. This short review will summarize the findings in this context that pertain to lactic acid bacteria isolated specifically from sourdough starters and acquaint the reader with the most recent advancements in this bio-preservation trend. [ABSTRACT FROM AUTHOR]

Patulin is a mycotoxin produced by a wide range of molds involved in fruit spoilage, most commonly by Penicillium expansum and is a health concern for both consumers and manufacturers. The current study evaluated feasibility of monochromatic ultraviolet (UV) radiation at 253.7 nm as a possible commercial application for the reduction of patulin in fresh apple cider and juice. The R-52G MINERALIGHT® UV bench top lamp was used for patulin destruction. It was shown that 56.5%, 87.5%, 94.8% and 98.6% reduction of patulin can be achieved, respectively, in the model solution, apple cider, apple juice without ascorbic acid addition and apple juice with ascorbic acid addition in 2-mm thickness sample initially spiked by 1 mg·L−1 of patulin after UV exposure for 40 min at UV irradiance of 3.00 mW·cm−2. A mathematic model to compare the degradation rate and effective UV dose was developed. The effective UV doses that were directly absorbed by patulin for photochemical reaction were 430, 674, 724 and 763 mJ·cm−3, respectively. The fluence-based decimal reduction time was estimated to 309.3, 31.3, 28.9 and 5.1 mW·cm−2·min, respectively, in four media mentioned above. The degradation of patulin followed the first-order reaction model. The time-based and fluence-based reaction rate constants were determined to predict patulin degradation. The time-based reaction rate constant of samples treated in dynamic regime with constant stirring (model solution: 2.95E-4 s−1, juice: 4.31E-4 s−1) were significantly higher than samples treated in static regime (model solution: 2.79E-4 s−1, juice: 3.49E-4 s−1, p < 0.05) when applied UV irradiance and sample thickness were consistent. The reaction rate constant of patulin degradation in apple juice was significantly higher than model solution (p < 0.05). Although further investigations are still needed, the results of this study demonstrated that UV radiation may be an effective method for treating patulin-containing apple cider and juice. [ABSTRACT FROM AUTHOR]

One hundred and fifty soil samples collected from different crop fields in southern Ontario, Canada were screened to obtain microorganisms capable of transforming deoxynivalenol (DON) to de-epoxy DON (dE-DON). Microbial DON to dE-DON transformation (i.e. de-epoxydation) was monitored by using liquid chromatography-ultraviolet-mass spectrometry (LC-UV-MS). The effects of growth substrates, temperature, pH, incubation time and aerobic versus anaerobic conditions on the ability of the microbes to de-epoxydize DON were evaluated. A mixed microbial culture from one composite soil sample showed 100% DON to dE-DON biotransformation in mineral salts broth (MSB) after 144 h of incubation. Treatments of the culture with selective antibiotics followed an elevated temperature (50°C) for 1.5 h considerably reduced the microbial diversity. Partial 16S-rRNA gene sequence analysis of the bacteria in the enriched culture indicated the presence of at least six bacterial genera, namely Serratia, Clostridium, Citrobacter, Enterococcus, Stenotrophomonas and Streptomyces. The enriched culture completely de-epoxydized DON after 60 h of incubation. Bacterial de-epoxydation of DON occurred at pH 6.0-7.5, and a wide array of temperatures (12-40°C). The culture showed rapid de-epoxydation activity under aerobic conditions compared to anaerobic conditions. This is the first report on microbial DON to dE-DON transformation under aerobic conditions and moderate temperatures. The culture could be used to detoxify DON contaminated feed and might be a potential source for gene(s) for DON de-epoxydation. [ABSTRACT FROM AUTHOR]

Abstract: The degradation of 12 trichothecene mycotoxins by chicken intestinal microbes was monitored by liquid chromatography–ultraviolet-mass spectrometry under positive ion atmospheric pressure chemical ionization. Two pathways were observed: deacylation and deepoxidation. Essentially complete conversions to the deepoxy metabolites were observed for the non-acylated trichothecenes 4-deoxynivalenol, nivalenol, and verrucarol. However, deacetylation was the predominant pathway for the monoacetyl trichothecenes 3-acetyldeoxynivalenol, 15-acetyldeoxynivalenol (15ADON), and fusarenon X. Small amounts of the deepoxy metabolites were observed from 15ADON and large amounts from 15-monoacetoxyscirpenol where steric hindrance protected the C-15 acetyl groups from enzymatic attack. Diacetylated trichothecenes diacetoxyscirpenol and neosolaniol exhibited only deacetylation. The larger isovaleryl functionality was resistant to removal and deepoxidation was the prevalent reaction in HT-2 toxin and T-2 triol, whereas T2 toxin showed only deacetylation. [Copyright &y& Elsevier]

Tea is welcomed by consumers worldwide for its unique flavor and multiple health-promoting components. However, there is still being challenge of tea regarding microbial contaminations during cultivating, processing, storage and transportation, and the risks of potential intake of mycotoxins from tea drinking. Based on available publications, this review summarized the results, discussed the conclusions and provided prospects on the topic of fungal and mycotoxin contaminations in the commonly recognized six tea categories, i.e. green tea, white tea, yellow tea, oolong tea, black tea and dark tea. For the results of contaminations and risks differ significantly in different studies, the advantages and disadvantages of such detection techniques and risk assessment method were thoroughly compared and discussed. The fungal floras vary greatly among the different teas, and are the most abundance and complex in dark teas. Certain fungal species being reported as toxigenic fungi were isolated from teas but their capability to produce mycotoxins on teas needs to be confirmed. The mycotoxins detected from teas include aflatoxins, ochratoxin A, fumonisins, deoxynivalenol, zearalenone and enniatins, but their occurrence and prevalence differ significantly in various tea categories and in different studies, especially being determined by different analytical methods. Dietary risks of mycotoxins from teas were low, but the sample sizes of teas and consumption data are very limited, and the cumulative risks should be assessed further using more appropriate methods based on large numbers of tea contamination data and dietary surveys. • Fungal flora contaminations in six different tea categories. • Mycotoxin contaminations in six different tea categories. • Mycotoxin analytical methods on tea matrix. • Shortcomings and prospects on mycotoxins risk assessments to tea drinking. [ABSTRACT FROM AUTHOR]

Apples and apple-based products are among the most popular foods around the world for their delightful flavors and health benefits. However, the commonly found mold, Penicillium expansum invades wounded apples, causing the blue mold decay and ensuing the production of patulin, a mycotoxin that negatively affects human health. Patulin contamination in apple products has been a worldwide problem without a satisfactory solution yet. A comprehensive understanding of the factors and challenges associated with patulin accumulation in apples is essential for finding such a solution. This review will discuss the effects of the pathogenicity of Penicillium species, quality traits of apple cultivars, and environmental conditions on the severity of apple blue mold and patulin contamination. Moreover, beyond the complicated interactions of the three aforementioned factors, patulin control is also challenged by the lack of reliable detection methods in food matrices, as well as unclear degradation mechanisms and limited knowledge about the toxicities of the metabolites resulting from the degradations. As apple-based products are mainly produced with stored apples, pre- and post-harvest strategies are equally important for patulin mitigation. Before storage, disease-resistance breeding, orchard-management, and elicitor(s) application help control the patulin level by improving the storage qualities of apples and lowering fruit rot severity. From storage to processing, patulin mitigation strategies could benefit from the optimization of apple storage conditions, the elimination of rotten apples, and the safe and effective detoxification or biodegradation of patulin. [ABSTRACT FROM AUTHOR]

Abstract: A total of 76 cereal and oil products collected from Yangtze Delta region of China were analyzed for occurrences of aflatoxins (AFs), aflatoxin B1 (AFB1), ochratoxin A (OTA), deoxynivalenol (DON) and zearalenone (ZEN). The mycotoxins were determined by the standard detection procedures using immunoaffinity column clean-up coupled with fluorometer (or HPLC-UV). ZEN was the most prevalent toxin, with the incidence of 27.6% (range = 10.0–440.0 μg kg−1), and 9.2% of the evaluated samples were contaminated with a concentration higher than that of the legislation limit of China (60 μg kg−1). AFs and AFB1 were detected in 14.5% of the samples analyzed, the concentrations ranging 1.1–35.0 μg kg−1 for AFs, and 1.0–32.2 μg kg−1 for AFB1; 4.0% of the samples had the concentrations of AFs and AFB1 higher than that of the corresponding legislation limits of China (5.0, 10.0 and 20.0 μg kg−1 for different products). OTA was detected in 14.5% of the cereal and oil products collected; the concentrations ranged 0.51–16.2 μg kg−1. Only 2 samples showed OTA levels higher than that of the legislation limit of China (5.0 μg kg−1). DON was detected in 7.9% of the samples; the concentrations ranged 100–700 μg kg−1, and none of the samples showed DON concentration higher than that of the legislation limit of China (1.0 mg kg−1). A total of 15.8% cereal and oil products were contaminated with at least two mycotoxins (multiple contaminations with different combinations including AFs-ZEN, AFs-OTA-ZEN, OTA-ZEN, ZEN-DON, OTA-ZEN-DON). The dietary exposure assessment results indicated that AFs (AFB1), OTA, DON and ZEN from cereal-based products represented a series health risk to both adults and children in Yangtze Delta region of China. This is the first report of safety evaluation associated with major mycotoxins for the area. [Copyright &y& Elsevier]

Abstract: Deoxynivalenol (DON) is a mycotoxin produced by several Fusarium species and is toxic to a wide range of organisms, including human beings and livestock. To produce large amounts of pure DON for research purposes, a novel method using high-speed counter-current chromatography (HSCCC) was developed. Rice cultured with Fusarium graminearum and field mouldy corn infected by F. graminearum were extracted with methanol and found to contain 1.16 and 1.30mg DON/g, respectively. The extracts were concentrated and then separated using a biphasic solvent system consisting of ethyl acetate–water (1:1, v/v). Collected fractions were analyzed by high-performance liquid chromatography (HPLC) and identified by congruent retention time and UV/vis spectrum and mass spectrometric data. Fractions containing DON were combined and freeze-dried. This method produced 116mg and 65mg DON with a purity of greater than 94.9% from 200g of the rice culture and the mouldy corn, respectively. The HSCCC method had a recovery rate of DON at 88% from the crude extracts of both samples. This one-step purification method provided a simple and effective tool for obtaining a large amount of DON, an essential material for studies related to toxicology and detoxification of this mycotoxin. [Copyright &y& Elsevier]

Abstract: The degradation of ten trichothecene mycotoxins by aqueous ozone was monitored by liquid chromatography–ultraviolet–mass spectrometry (LC–UV–MS). Saturated aqueous ozone (∼25ppm) degraded these mycotoxins to materials that were not detected by UV or MS. At lower levels (∼0.25ppm) of aqueous ozone, intermediate products were observed. On the basis of UV and MS data, it is proposed that the degradation begins with attack of ozone at the C9–10 double bond with the net addition of two atoms of oxygen. The remainder of the molecule appears to have been left unaltered. The oxidation state at the allylic carbon 8 position had a significant effect on the ease of reaction, as determined by moles of ozone required to effect oxidation. The amount of ozone required to effect oxidation to intermediate products and subsequent degradation followed the series allylic methylene (no oxygen)

Mycotoxins are secondary metabolites produced by specific fungi that can be found throughout the dietary chain of animal feed. Among the agriculturally important mycotoxins are: aflatoxin B 1 (AFB 1 ), deoxynivalenol (DON), zearalenone (ZEA), nivalenol (NIV), fumonisin B 1 (FUB 1 ), ochratoxin A (OTA), citrinin (CIT) and patulin (PAT). Economic losses and health concerns caused by increased frequencies of mycotoxin contaminations have attracted research interests toward exploring new inactivation and detoxification methods. Suggested strategies of decontamination include eliminating mycotoxins from contaminated grains, decreasing the bioavailability of such mycotoxins in the gastrointestinal tracts of animals, or directly degrading mycotoxins in feeds. Based on these points of action, a number of approaches such as adsorption, chemical treatment, and bio-transformation by catabolizing microorganisms/enzymes have been developed and optimized. This review summarizes the detoxification techniques and industrial applications (granted and pending patents) reported in the last five years (2010–2015). A clear understanding of such novel detoxification methods and development-trends can be beneficial to the feed and livestock industry and will contribute to assuring pre- and post-harvest management and processing practices are in place that maximizes the consumers’ safety and profits of livestock and related industries. [ABSTRACT FROM AUTHOR]

Abstract: Trichothecene mycotoxins are commonly found in cereals worldwide and bring significant threats to the food industry and animal production. The aim of this research was to search for microbes from fish guts capable of transforming trichothecenes into less toxic compounds. Digesta of 62 fishes from nine species were screened for their ability to transform 4-deoxynivalenol (DON). Liquid chromatography-mass spectrometry was used to determine the reduction of DON concentrations and structures of DON-transformation products. The microbial community from one catfish Ameiurus nebulosus, namely microbial culture C133, completely transformed DON to deepoxy DON (dE-DON) at 15 °C in full medium after 96 h incubation. Various media and culture conditions were tested to evaluate their effect on DON transformation. Microbial culture C133 maintained high transformation ability over a broad range of temperatures from 4 to 25 °C and pH values from 4.5 to 10.4. The transformation of DON to dE-DON was enhanced in a rich medium such as full medium, nutrient broth and corn meal broth. Microbial culture C133 was then tested for its ability to transform other trichothecene mycotoxins; most of the toxins were transformed to deacetyl and/or deepoxy products. This is the first report on trichothecene transformation by microbes from the intestinal tract of fish. [Copyright &y& Elsevier]

Ingestion of deoxynivalenol (DON), one of the most common mycotoxin contaminants of cereals, leads to adverse effects for animal and human health. Bacterial biotransformation is a strategy to mitigate the toxicity of this mycotoxin. The present study aims to evaluate the toxicity of two bacterial biotranformation products of DON: 3-epi-deoxynivalenol (3-epi-DON) and de-epoxy-deoxynivalenol (DOM-1) through zootechnical, hematological, histological and immunological assays. Twenty-four 4-weeks-old piglets received a control diet or a diet contaminated with 3 mg kg−1 DON, DOM-1, or 3-epi-DON for 7 days. Sample tissues were collected for histomorphometrical analysis, expression of cytokines and cell protein junctions. The zootechnical and hematological parameters were not modulated by any treatment. Ingestion of DON induced histological alterations in the intestine, liver and lymphoid organs, as well as an overexpression of pro-inflammatory cytokines, E-cadherin and occludin. These changes were not observed in piglets receiving the DOM-1 and 3-epi-DON contaminated diets. Pigs fed 3-epi-DON contaminated diet showed an increase in IgM levels in comparison with other diets, while no change was observed in IgA and IgG levels among the diets. Our results indicate that DOM-1 and 3-epi-DON are not toxic for piglets; thus bacterial biotransformation seems to be a sustainable alternative to reduce mycotoxin toxicity. • Ingestion of DON induces tissue changes and overexpression of proinflammatory cytokines and cell junction proteins in pigs. • Bacterial biotransformation seems to be a sustainable alternative to reduce mycotoxintoxicity • Bacterial biotransformation seems to be a sustainable alternative to reduce mycotoxintoxicity. [ABSTRACT FROM AUTHOR]