Biological Control and Post-Harvest Detoxification of Mycotoxins as Strategies to Reduce the Impact of Mycotoxins

A special issue of Toxins (ISSN 2072-6651). This special issue belongs to the section "Mycotoxins".

Deadline for manuscript submissions: closed (28 February 2019) | Viewed by 108270

Special Issue Editors


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Guest Editor
Department of Pharmacology, Toxicology and Biochemistry, Ghent University, 9820 Merelbeke, Belgium
Interests: mycotoxins; toxicokinetics; toxicity; binders; modifiers; in vitro; in vivo; food production animals; porcine biomedical model for humans; bioanalysis; biomarkers; cytochrome P450; ABC transporters; impact on infectious diseases; veterinary drugs; pharmacokinetics; pharmacodynamics; PK/PD modeling; residues; food safety
Special Issues, Collections and Topics in MDPI journals

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Guest Editor
Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Valentin Vaerwyckweg 1, 9000 Ghent, Belgium
Interests: plant–pathogen interactions; biocontrol; endophytic fungi; green leaf volatiles (GLVs); biogenic volatile compounds (BVOCs); plant defense priming; plant hormones; phenomics; genome-editing in fungi; plant defense pathways; biodegradation of mycotoxins; mycotoxin prediction and modelling; bioassays to assess toxicity of trichothecenes and their derivatives
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Mycotoxins are inherent to many food and feed products worldwide. Hallmarks of their presence and their impact on animal and human health are encountered throughout history. Ergotism, also known as ‘St. Anthony’s fire’ occurred in several areas in Europe during the tenth century and was caused by the consumption of rye containing ergot alkaloids, produced by the fungus Claviceps purpurea. In 1962, 100,000 turkeys died in the South Eastern area of England of Turkey X disease, linked to aflatoxins from Aspergillus flavus.

Driven by this impact of mycotoxins throughout history, research efforts progressively increased to develop mitigation strategies based on risk monitoring, risk characterization, prevention, intervention and remediation strategies for multiple mycotoxins. However, monitoring and good agricultural, storage and transportation practices along with an effective Hazard Analysis and Critical Control Point approach do not completely prevent mycotoxin presence in the food or feed chain.

Therefore, permanent research efforts are needed which explore new strategies to avoid mycotoxin occurrence during growth of the crop or to reduce mycotoxins during later processing. Although chemical control of toxigenic fungi is by far the most efficient, new legislation on a more sustainable and restricted use of fungicides urges for new approaches.

Two interesting strategies to reduce mycotoxins are biocontrol and mycotoxin detoxification. Biocontrol, which is often applied in the field during growth of the crop, comprises the use of living organisms to control a pathogen.

Biocontrol strategies are often not enough to eradicate a pathogenic species, but they control the invader in a way that it becomes manageable. Optimal biocontrol of toxigenic fungal species should not only result in reduced fungal load but should also result in reduced mycotoxin levels.

Mycotoxin detoxification strategies are often applied post-harvest. These strategies comprise several approaches such as chemical removal, physical binding, or biological degradation of mycotoxins.

In the present Special Issue, we welcome both original research and review articles on biocontrol and post-harvest detoxification strategies of the most important mycotoxins.

Prof. Dr. Siska Croubels
Prof. Dr. Kris Audenaert
Guest Editors

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Keywords

  • mycotoxins
  • biocontrol
  • biological detoxification
  • micro-organisms
  • chemical detoxification
  • physical detoxification
  • competition for niche
  • antibiosis
  • induced systemic resistance

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Published Papers (21 papers)

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18 pages, 2037 KiB  
Article
Distinct Transcriptional Changes in Response to Patulin Underlie Toxin Biosorption Differences in Saccharomyces cerevisiae
by Christian I. Oporto, Carlos A. Villarroel, Sebastián M. Tapia, Verónica García and Francisco A. Cubillos
Toxins 2019, 11(7), 400; https://doi.org/10.3390/toxins11070400 - 10 Jul 2019
Cited by 11 | Viewed by 4102
Abstract
Patulin (4-hydroxy-4H-furo[3,2c]pyran-2[6H]-one) is a mycotoxin produced by a suite of fungi species. Patulin is toxic to humans and is a sporadic contaminant in products that were made from fungi-infected fruits. The baker yeast Saccharomyces cerevisiae (S. cerevisiae) has been shown to decrease patulin [...] Read more.
Patulin (4-hydroxy-4H-furo[3,2c]pyran-2[6H]-one) is a mycotoxin produced by a suite of fungi species. Patulin is toxic to humans and is a sporadic contaminant in products that were made from fungi-infected fruits. The baker yeast Saccharomyces cerevisiae (S. cerevisiae) has been shown to decrease patulin levels likely by converting it to the less harmful E-ascladiol, yet this capacity is dependent on the strain utilized. In this study we show that four representative strains of different S. cerevisiae lineages differ in their ability to tolerate and decrease patulin levels in solution, demonstrating that some strains are better suitable for patulin biocontrol. Indeed, we tested the biocontrol capacities of the best patulin-reducer strain (WE) in contaminated apple juice and demonstrated their potential role as an efficient natural biocontrol solution. To investigate the mechanisms behind the differences between strains, we explored transcriptomic changes of the top (WE strain) and worst (WA strain) patulin-biocontroller strains after being exposed to this toxin. Large and significant gene expression differences were found between these two strains, the majority of which represented genes associated with protein biosynthesis, cell wall composition and redox homeostasis. Interestingly, the WE isolate exhibited an overrepresentation of up-regulated genes involved in membrane components, suggesting an active role of the membrane towards patulin detoxification. In contrast, WA upregulated genes were associated with RNA metabolism and ribosome biogenesis, suggesting a patulin impact upon transcription and translation activity. These results suggest that different genotypes of S. cerevisiae encounter different stresses from patulin toxicity and that different rates of detoxification of this toxin might be related with the plasma membrane composition. Altogether, our data demonstrates the different molecular mechanisms in S. cerevisiae strains withstanding patulin exposure and opens new avenues for the selection of new patulin biocontroller strains. Full article
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16 pages, 2506 KiB  
Article
Recombinant Aflatoxin-Degrading F420H2-Dependent Reductase from Mycobacterium smegmatis Protects Mammalian Cells from Aflatoxin Toxicity
by Che-Hsing Li, Wei-Yang Li, I-Ning Hsu, Yung-Yu Liao, Chi-Ya Yang, Matthew C. Taylor, Yu-Fan Liu, Wei-Hao Huang, Hsiang-Hua Chang, Ho-Lo Huang, Shao-Chi Lo, Ting-Yu Lin, Wei-Che Sun, Ya-Yi Chuang, Yu-Chieh Yang, Ru-Huei Fu and Rong-Tzong Tsai
Toxins 2019, 11(5), 259; https://doi.org/10.3390/toxins11050259 - 8 May 2019
Cited by 25 | Viewed by 4325
Abstract
Aflatoxins are carcinogenic secondary metabolites of fungi that contaminate many staple crops and foods. Aflatoxin contamination is a worldwide problem, especially in developing countries, posing health hazards, e.g., causing aflatoxicosis and hepatocellular carcinoma, and even death. Biological solutions for aflatoxin detoxification are environmentally [...] Read more.
Aflatoxins are carcinogenic secondary metabolites of fungi that contaminate many staple crops and foods. Aflatoxin contamination is a worldwide problem, especially in developing countries, posing health hazards, e.g., causing aflatoxicosis and hepatocellular carcinoma, and even death. Biological solutions for aflatoxin detoxification are environmentally friendly and a cheaper alternative than chemical methods. The aims of the current study were to investigate: (1) the ability of MSMEG_5998, an aflatoxin-degrading F420H2-dependent reductase from Mycobacterium smegmatis, to degrade aflatoxin B1 (AFB1) and reduce AFB1-caused damage in HepG2 cell culture model; and (2) whether a thioredoxin (Trx) linkage of MSMEG_5998 enhanced the enzyme activity. We show that Trx-linked MSMEG_5998 degraded 63% AFB1 and native MSMEG_5998 degraded 31% after 4 h at 22 °C, indicating that the Trx-linked enzyme had a better AFB1-degrading ability. In a HepG2 cell culture model, Trx-linked MSMEG_5998 reduced DNA damage and p53-mediated apoptosis caused by AFB1 to a greater extent than the native enzyme. These findings suggest that Trx-linked MSMEG_5998 could potentially be developed to protect the liver from AFB1 damage, or as a candidate protein to reduce AFB1-related toxicity in animals. Full article
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12 pages, 2700 KiB  
Communication
Mycotoxin Decontamination Efficacy of Atmospheric Pressure Air Plasma
by Nataša Hojnik, Martina Modic, Gabrijela Tavčar-Kalcher, Janja Babič, James L. Walsh and Uroš Cvelbar
Toxins 2019, 11(4), 219; https://doi.org/10.3390/toxins11040219 - 12 Apr 2019
Cited by 48 | Viewed by 6057
Abstract
Mycotoxins, the toxic secondary metabolites of mould species, are a growing global concern, rendering almost 25% of all food produced unfit for human or animal consumption, thus placing immense pressure on the food supply chain. Cold Atmospheric pressure Plasma (CAP) represents a promising, [...] Read more.
Mycotoxins, the toxic secondary metabolites of mould species, are a growing global concern, rendering almost 25% of all food produced unfit for human or animal consumption, thus placing immense pressure on the food supply chain. Cold Atmospheric pressure Plasma (CAP) represents a promising, low-cost, and environmentally friendly means to degrade mycotoxins with negligible effect on the quality of food products. Despite this promise, the study of CAP-mediated mycotoxin degradation has been limited to a small subset of the vast number of mycotoxins that plague the food supply chain. This study explores the degradation of aflatoxins, trichothecenes, fumonisins, and zearalenone using CAP generated in ambient air. CAP treatment was found to reduce aflatoxins by 93%, trichothecenes by 90%, fumonisins by 93%, and zearalenone by 100% after 8 minutes exposure. To demonstrate the potential of CAP-mediated mycotoxin degradation against more conventional methods, its efficiency was compared against ultraviolet C (UVC) light irradiation. In all cases, CAP was found to be considerably more efficient than UVC, with aflatoxin G1 and zearalenone being completely degraded, levels that could not be achieved using UVC irradiation. Full article
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21 pages, 6464 KiB  
Article
Biomarkers for Exposure as a Tool for Efficacy Testing of a Mycotoxin Detoxifier in Broiler Chickens and Pigs
by Marianne Lauwers, Siska Croubels, Ben Letor, Christos Gougoulias and Mathias Devreese
Toxins 2019, 11(4), 187; https://doi.org/10.3390/toxins11040187 - 28 Mar 2019
Cited by 31 | Viewed by 6634
Abstract
Applying post-harvest control measures such as adding mycotoxin detoxifying agents is a frequently-used mitigation strategy for mycotoxins. EFSA states that the efficacy of these detoxifiers needs to be tested using specific biomarkers for exposure. However, the proposed biomarkers for exposure are not further [...] Read more.
Applying post-harvest control measures such as adding mycotoxin detoxifying agents is a frequently-used mitigation strategy for mycotoxins. EFSA states that the efficacy of these detoxifiers needs to be tested using specific biomarkers for exposure. However, the proposed biomarkers for exposure are not further optimized for specific target species. Hence, the goal of this study was (a) to evaluate the most suitable biomarkers for deoxynivalenol (DON) and zearalenone (ZEN) in porcine plasma, urine and feces; and DON, aflatoxin B1 (AFB1) and ochratoxin A (OTA) in plasma and excreta of broiler chickens and (b) to determine the efficacy of a candidate detoxifier, as a proof-of-concept study. Therefore, a mixture of mycotoxins was administered as a single oral bolus with or without detoxifying agent. In accordance with literature AFB1, OTA, and DON-sulphate (DON-S) proved optimal biomarkers in broilers plasma and excreta whereas, in pigs DON-glucuronide (DON-GlcA) and ZEN-glucuronide (ZEN-GlcA) proved the optimal biomarkers in plasma, DON and ZEN-GlcA in urine and, ZEN in feces. A statistically significant reduction was seen between control and treatment group for both AFB1 and DON in broiler plasma, under administration of the mycotoxin blend and detoxifier dose studied suggesting thus, beneficial bioactivity. Full article
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18 pages, 2021 KiB  
Article
The Development of a qPCR Assay to Measure Aspergillus flavus Biomass in Maize and the Use of a Biocontrol Strategy to Limit Aflatoxin Production
by Alfred Mitema, Sheila Okoth and Suhail M. Rafudeen
Toxins 2019, 11(3), 179; https://doi.org/10.3390/toxins11030179 - 25 Mar 2019
Cited by 12 | Viewed by 4423 | Correction
Abstract
Aspergillus flavus colonisation of maize can produce mycotoxins that are detrimental to both human and animal health. Screening of maize lines, resistant to A. flavus infection, together with a biocontrol strategy, could help minimize subsequent aflatoxin contamination. We developed a qPCR assay to [...] Read more.
Aspergillus flavus colonisation of maize can produce mycotoxins that are detrimental to both human and animal health. Screening of maize lines, resistant to A. flavus infection, together with a biocontrol strategy, could help minimize subsequent aflatoxin contamination. We developed a qPCR assay to measure A. flavus biomass and showed that two African maize lines, GAF4 and KDV1, had different fungal loads for the aflatoxigenic isolate (KSM014), fourteen days after infection. The qPCR assay revealed no significant variation in A. flavus biomass between diseased and non-diseased maize tissues for GAF4, while KDV1 had a significantly higher A. flavus biomass (p < 0.05) in infected shoots and roots compared to the control. The biocontrol strategy using an atoxigenic isolate (KSM012) against the toxigenic isolate (KSM014), showed aflatoxin production inhibition at the co-infection ratio, 50:50 for both maize lines (KDV1 > 99.7% and GAF ≥ 69.4%), as confirmed by bioanalytical techniques. As far as we are aware, this is the first report in Kenya where the biomass of A. flavus from maize tissue was detected and quantified using a qPCR assay. Our results suggest that maize lines, which have adequate resistance to A. flavus, together with the appropriate biocontrol strategy, could limit outbreaks of aflatoxicoses. Full article
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13 pages, 1067 KiB  
Article
Effect of Compound Probiotics and Mycotoxin Degradation Enzymes on Alleviating Cytotoxicity of Swine Jejunal Epithelial Cells Induced by Aflatoxin B1 and Zearalenone
by Weiwei Huang, Juan Chang, Ping Wang, Chaoqi Liu, Qingqiang Yin, Andong Song, Tianzeng Gao, Xiaowei Dang and Fushan Lu
Toxins 2019, 11(1), 12; https://doi.org/10.3390/toxins11010012 - 10 Jan 2019
Cited by 30 | Viewed by 4942
Abstract
Zearalenone (ZEA) and aflatoxin B1 (AFB1) are two main kinds of mycotoxins widely existing in grain and animal feed that cause a lot of economic loss and health problems for animals and humans. In order to alleviate the cytotoxic effects [...] Read more.
Zearalenone (ZEA) and aflatoxin B1 (AFB1) are two main kinds of mycotoxins widely existing in grain and animal feed that cause a lot of economic loss and health problems for animals and humans. In order to alleviate the cytotoxic effects of AFB1 and ZEA on swine jejunal epithelial cells (IPEC-J2), the combination of a cell-free supernatant of compound probiotics (CFSCP) with mycotoxin degradation enzymes (MDEs) from Aspergillus oryzae was tested. The results demonstrated that coexistence of AFB1 and ZEA had synergetic toxic effects on cell viability. The cell viability was decreased with mycotoxin concentrations increasing, but increased with incubation time extension. The necrotic cell rates were increased when 40 µg/L AFB1 and/or 500 µg/L ZEA were added, but the addition of CFSCP + MDE suppressed the necrotic effects of AFB1 + ZEA. The viable cell rates were decreased when AFB1 and/or ZEA were added: However, the addition of CFSCP + MDE recovered them. The relative mRNA abundances of Bcl-2, occludin, and ZO-1 genes were significantly upregulated, while Bax, caspase-3, GLUT2, ASCT2, PepT1, and IL6 genes were significantly downregulated by CFSCP + MDE addition, compared to the groups containing 40 µg/L AFB1 and 500 µg/L ZEA. This research provided an effective strategy in alleviating mycotoxin cytotoxicity and keeping normal intestinal cell structure and animal health. Full article
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15 pages, 1979 KiB  
Article
Grape Seed Proanthocyanidin Extract Alleviates AflatoxinB1-Induced Immunotoxicity and Oxidative Stress via Modulation of NF-κB and Nrf2 Signaling Pathways in Broilers
by Shahid Ali Rajput, Lvhui Sun, Ni-Ya Zhang, Mahmoud Mohamed Khalil, Zhao Ling, Li Chong, Shuai Wang, Imran Rashid Rajput, Dost Muhammad Bloch, Farhan Anwar Khan, Aftab Shaukat and Desheng Qi
Toxins 2019, 11(1), 23; https://doi.org/10.3390/toxins11010023 - 7 Jan 2019
Cited by 58 | Viewed by 6040
Abstract
Aflatoxin B1 (AFB1) is a widely spread mycotoxin contaminates food and feed, causing severe oxidative stress damages and immunotoxicity. Grape seed proanthocyanidin (GSPE), a natural antioxidant with wide range of pharmacological and medicinal properties. The goal of the present study [...] Read more.
Aflatoxin B1 (AFB1) is a widely spread mycotoxin contaminates food and feed, causing severe oxidative stress damages and immunotoxicity. Grape seed proanthocyanidin (GSPE), a natural antioxidant with wide range of pharmacological and medicinal properties. The goal of the present study was to investigate the protective effects of GSPE against AFB1-induced immunotoxicity and oxidative stress via NF-κB and Nrf2 signaling pathways in broiler chickens. For the experiment, 240 one-day old Cobb chicks were allocated into four dietary treatment groups of six replicates (10 birds per replicate): 1. Basal diet (control); 2. Basal diet + AFB1 1mg/kg contaminated corn (AFB1); 3. Basal diet + GSPE 250 mg/kg (GSPE); 4. Basal diet + AFB1 1 mg/kg + GSPE 250 mg/kg (AFB1 + GSPE). The results showed that GSPE significantly decreased serum inflammatory cytokines TNF-α, IFN-γ, IL-1β, IL-10, and IL-6 induced by AFB1. Similarly, GSPE + AFB1 treated group revealed a significant decrease in mRNA expressions of pro-inflammatory cytokines (TNF-α, IFN-γ, IL-1β, and IL-6) in the splenic tissue compared to the AFB1 treatment group. In addition, western blotting results manifested that GSPE treatment normalized the phosphorylation of nuclear factor kappa B (p65) and the degradation of IκBα protein induced by AFB1. Furthermore, GSPE enhanced the antioxidant defense system through activating the nuclear factor-erythroid-2-related factor (Nrf2) signaling pathway. The mRNA and protein expression level of Nrf2 and its down streaming associated genes were noted up-regulated by the addition of GSPE, and down-regulated in the AFB1 group. Taken together, GSPE alleviates AFB1-induced immunotoxicity and oxidative damage by inhibiting the NF-κB and activating the Nrf2 signaling pathways in broiler chickens. Conclusively, our results suggest that GSPE could be considered as a potential natural agent for the prevention of AFB1-induced immunotoxicity and oxidative damage. Full article
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11 pages, 3726 KiB  
Article
Optimization of Storage Conditions of the Medicinal Herb Ilex asprella against the Sterigmatocystin Producer Aspergillus versicolor Using Response Surface Methodology
by Xiaofang Lu, Chaoquan Luo, Jianyong Xing, Zhengzhou Han, Tong Li, Weiwei Wu, Hui Xu, Ruoting Zhan and Weiwen Chen
Toxins 2018, 10(12), 499; https://doi.org/10.3390/toxins10120499 - 27 Nov 2018
Cited by 5 | Viewed by 3202
Abstract
The root of Ilex asprella is a commonly used herb in Southern China, and also constitutes the main raw material of Canton herbal tea. I. asprella is readily contaminated by mildew because of rich nutrients. Aspergillus versicolor producing sterigmatocystin is one of the [...] Read more.
The root of Ilex asprella is a commonly used herb in Southern China, and also constitutes the main raw material of Canton herbal tea. I. asprella is readily contaminated by mildew because of rich nutrients. Aspergillus versicolor producing sterigmatocystin is one of the most common molds that contaminate foodstuffs and medicinal herbs. Previous study on the evaluation of fungal contamination on samples of I. asprella revealed that A. versicolor was the dominant contaminant. In this study, experiments based on response surface methodology combined with central composite design were carried out to determine the optimal storage conditions of I. asprella to minimize the contamination of sterigmatocystin. The herb, manually innoculated with A. versicolor, was stored under different temperatures (20–40 °C) and humidity (80–95%) for seven days. The effects of temperature and humidity were evaluated using total saponin, polysaccharide and the sterigmatocystin levels as quality indexes. The results showed that A. versicolor grew quickly and produced large amounts of sterigmatocystin on I. asprella, at humidity ranging from 85% to 90% and temperatures above 26 °C. Meanwhile, total saponin and polysaccharide amounts were reduced significantly. These findings suggested that I. asprella samples should be stored in an environment with humidity and temperature below 85% and 26 °C, respectively, to reduce A. versicolor growth and sterigmatocystin production. Full article
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18 pages, 2513 KiB  
Article
Fungal Endophytes Control Fusarium graminearum and Reduce Trichothecenes and Zearalenone in Maize
by Mohamed F. Abdallah, Marthe De Boevre, Sofie Landschoot, Sarah De Saeger, Geert Haesaert and Kris Audenaert
Toxins 2018, 10(12), 493; https://doi.org/10.3390/toxins10120493 - 24 Nov 2018
Cited by 48 | Viewed by 6060
Abstract
Fusarium graminearum can cause Giberella Ear Rot (GER) and seedling blight in maize, resulting in major yield losses. Besides GER, the infected grains are consequently contaminated with multiple mycotoxins of F. graminearum. Zearalenone and trichothecenes, such as deoxynivalenol and its acetylated forms, [...] Read more.
Fusarium graminearum can cause Giberella Ear Rot (GER) and seedling blight in maize, resulting in major yield losses. Besides GER, the infected grains are consequently contaminated with multiple mycotoxins of F. graminearum. Zearalenone and trichothecenes, such as deoxynivalenol and its acetylated forms, are among the major mycotoxins associated with F. graminearum infection in maize. In the current work, we explored the effect of the endophytic fungal genera of Epicoccum and Sordaria, to control F. graminearum infection in comparative trials with Piriformospora spp., an elusive endophytic genus. Furthermore, we investigated the effect of these endophytes on zearalenone, deoxynivalenol, and 15-acetyldeoxynivalenol levels using in vitro and in planta assays. As plants are endowed with several detoxification mechanisms comprising e.g., glucosylation of trichothecenes, the effect of the isolated fungal endophytes on the deoxynivalenol-3-glucoside level was also assessed. In general, results showed a considerable variability in the antifungal activity, both among species and among isolates within one species. Additionally, the effect on mycotoxin levels was variable, and not necessarily related to the antifungal activity except for zearalenone levels which were consistently reduced by the endophytes. These results highlight the great potential of certain endophytic fungal strains as new biocontrol agents in agricultural science. Full article
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16 pages, 1402 KiB  
Article
Assessing the Aflatoxin B1 Adsorption Capacity between Biosorbents Using an In Vitro Multicompartmental Model Simulating the Dynamic Conditions in the Gastrointestinal Tract of Poultry
by Anai Zavala-Franco, Daniel Hernández-Patlán, Bruno Solís-Cruz, Raquel López-Arellano, Guillermo Tellez-Isaias, Alma Vázquez-Durán and Abraham Méndez-Albores
Toxins 2018, 10(11), 484; https://doi.org/10.3390/toxins10110484 - 21 Nov 2018
Cited by 30 | Viewed by 6158
Abstract
Experiments were carried out to evaluate the effectiveness of three different biosorbents (banana peel, Pyracantha leaves, and Aloe powder) in removing aflatoxin B1 (AFB1). A noncommercial mycotoxin binder (zeolite) was used as a reference material. A laboratory model that simulated [...] Read more.
Experiments were carried out to evaluate the effectiveness of three different biosorbents (banana peel, Pyracantha leaves, and Aloe powder) in removing aflatoxin B1 (AFB1). A noncommercial mycotoxin binder (zeolite) was used as a reference material. A laboratory model that simulated the in vivo conditions of the poultry gastrointestinal tract was utilized to prove the removal efficiency of the biosorbents when added to AFB1-contaminated diet (100 µg/kg). The concentration of AFB1 was determined using antibody-based immunoaffinity column and spectrofluorometry methodologies. Z potential (ζ), point of zero charge (pHpzc), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), Fourier transform infrared spectroscopy with attenuated total reflection (FTIR-ATR), and UV-Vis diffuse reflectance spectroscopy (DRS) techniques were used to further characterize the biosorbents. The addition of the biosorbents (1.5%, w/w) to the diet significantly reduced the bioavailability of AFB1 in the intestinal section. The highest aflatoxin adsorption values were 69% and 70% using Aloe powder and zeolite, respectively. A moderate biosorption uptake of 46% was achieved using Pyracantha leaves. The biomaterial with the lowest removal capacity was banana peel (28%). In conclusion, Aloe powder could be used as an alternative to conventional systems for AFB1 removal. Full article
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16 pages, 3164 KiB  
Article
The Protective Role of Bacillus velezensis A2 on the Biochemical and Hepatic Toxicity of Zearalenone in Mice
by Nan Wang, Peng Li, Mingyang Wang, Si Chen, Sheng Huang, Miao Long, Shuhua Yang and Jianbin He
Toxins 2018, 10(11), 449; https://doi.org/10.3390/toxins10110449 - 31 Oct 2018
Cited by 22 | Viewed by 4542
Abstract
Zearalenone (ZEN) is an estrogen-like mycotoxin produced by Fusarium that seriously compromises the safety of animal and human health. In this study, our aim was to evaluate the protective effect of Bacillus velezensis A2 against biochemical and pathological changes induced by zearalenone in [...] Read more.
Zearalenone (ZEN) is an estrogen-like mycotoxin produced by Fusarium that seriously compromises the safety of animal and human health. In this study, our aim was to evaluate the protective effect of Bacillus velezensis A2 against biochemical and pathological changes induced by zearalenone in mice. Kunming mice (n = 40; 25 ± 2 g) were allotted to four treatment groups: a control group (basic feed); a ZEN group (basic feed with a ZEN dose of 60 mg/kg); an A2 strain fermented feed group (150 g of feed mixed with 150 mL of sterile distilled water and inoculated with 5 mL of phosphate buffer salt (PBS) resuspended A2 strain); and an A2 strain fermented ZEN-contaminated feed group. (A2 strain group 150 mL pure bacterial distilled water system mixed with 150 g ZEN-contaminated feed.) Our results showed that the Bacillus velezensis A2 strain can completely degrade the ZEN-contaminated feed within 5 days. (The concentration of ZEN in fermentation was 60 μg/mL.) After the mice fed for 28 days, compared with the control group, the activities of AST and ALT were increased, the activities of glutathione peroxidase (GSH-PX) and total superoxide dismutase (T-SOD) were decreased, and the amount of creatinine (CRE), blood urea nitrogen (BUN), uric acid (UA), and malondialdehyde (MDA) in the ZEN group were increased in the mice serum (p < 0.05; p < 0.01). However, compared with the ZEN group, these biochemical levels were reversed in the A2 strain fermented feed group and in the A2 strain fermented ZEN-contaminated feed group (p < 0.05; p < 0.01). Furthermore, histopathological analysis only showed pathological changes of the mice liver in the ZEN group. The results showed that Bacillus velezensis A2 as additive could effectively remove ZEN contamination in the feed and protect the mice against the toxic damage of ZEN. In conclusion, Bacillus velezensis A2 has great potential use as a microbial feed additive to detoxify the toxicity of zearalenone in production practice. Full article
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13 pages, 1888 KiB  
Article
A Novel Adsorbent Magnetic Graphene Oxide Modified with Chitosan for the Simultaneous Reduction of Mycotoxins
by Atena Abbasi Pirouz, Roghayeh Abedi Karjiban, Fatimah Abu Bakar and Jinap Selamat
Toxins 2018, 10(9), 361; https://doi.org/10.3390/toxins10090361 - 6 Sep 2018
Cited by 24 | Viewed by 4155
Abstract
A novel magnetic graphene oxide modified with chitosan (MGO-CTS) was synthesised as an adsorbent aimed to examine the simultaneous removal of mycotoxins. The composite was characterised by various procedures, namely Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and a scanning electron microscope (SEM). [...] Read more.
A novel magnetic graphene oxide modified with chitosan (MGO-CTS) was synthesised as an adsorbent aimed to examine the simultaneous removal of mycotoxins. The composite was characterised by various procedures, namely Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and a scanning electron microscope (SEM). The adsorption evaluation was considered via pH effects, initial mycotoxin concentration, adsorption time and temperature. Adsorption isotherm data and kinetics experiments were acquired at the optimum pH 5 fit Freundlich isotherm as well as pseudo-second-order kinetic models. The thermodynamic results indicated that the adsorption of the mycotoxins was spontaneous, endothermic and favourable. Full article
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16 pages, 3762 KiB  
Article
Effective Adsorption of Patulin from Apple Juice by Using Non-Cytotoxic Heat-Inactivated Cells and Spores of Alicyclobacillus Strains
by Marina Sajid, Sajid Mehmood, Chen Niu, Yahong Yuan and Tianli Yue
Toxins 2018, 10(9), 344; https://doi.org/10.3390/toxins10090344 - 25 Aug 2018
Cited by 27 | Viewed by 4331
Abstract
Patulin (PAT) is a major threat to many food products, especially apple and apple products, causing human health risks and economic losses. The aim of this study was to remove PAT from apple juice by using the heat-inactivated (HI) cells and spores of [...] Read more.
Patulin (PAT) is a major threat to many food products, especially apple and apple products, causing human health risks and economic losses. The aim of this study was to remove PAT from apple juice by using the heat-inactivated (HI) cells and spores of seven Alicyclobacillus strains under controlled conditions. The HI cells and spores of seven strains adsorbed PAT effectively, and the HI cells and spores of Alicyclobacillus acidocaldarius DSM 451 (A51) showed maximum PAT adsorption capacity of up to 12.6 μg/g by HI cells and 11.8 μg/g by HI spores at 30 °C and pH 4.0 for 24 h. Moreover, the PAT adsorption process followed the pseudo-first order kinetic model and the Freundlich isotherm model; thermodynamic parameters revealed that PAT adsorption is a spontaneous exothermic physisorption process. The results also indicated that PAT adsorption is strain-specific. The HI cells and spores of Alicyclobacillus strains are non-cytotoxic, and the bioadsorption of PAT did not affect the quality of the juice. Furthermore, the cell wall surface plays an important role in the adsorption process. Full article
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10 pages, 274 KiB  
Article
Effects of Feeding a Mycotoxin Binder on Nutrient Digestibility, Alkaloid Recovery in Feces, and Performance of Lambs Fed Diets Contaminated with Cereal Ergot
by Kim Stanford, Mary Lou Swift, Yuxi Wang, Tim A. McAllister, John McKinnon, Barry Blakley and Alex V. Chaves
Toxins 2018, 10(8), 312; https://doi.org/10.3390/toxins10080312 - 1 Aug 2018
Cited by 12 | Viewed by 4553
Abstract
As contamination with cereal ergot has been increasing in western Canada, this study evaluated impacts of feeding a mycotoxin binder (Biomin® II; BB) on nutrient digestibility, alkaloid recovery in feces, and lamb growth performance. Forty-eight ram lambs (25.9 ± 1.4 kg) were [...] Read more.
As contamination with cereal ergot has been increasing in western Canada, this study evaluated impacts of feeding a mycotoxin binder (Biomin® II; BB) on nutrient digestibility, alkaloid recovery in feces, and lamb growth performance. Forty-eight ram lambs (25.9 ± 1.4 kg) were randomly assigned to one of four barley-based diets: Control (C), no added alkaloids, Control + BB fed at 30 g/head per day (CBB); Ergot, 2564 ppb total R + S epimers (E); Ergot + BB, 2534 ppb R + S epimers (EBB). Lambs were fed ab libitum for up to 11 weeks until slaughter at >46 kg live weight. Both average daily gain (ADG) and gain/feed ratio were greater (p < 0.01) for lambs fed C and CBB diets as compared with those containing added ergot, although dry matter intake was not affected by dietary ergot or BB. Serum prolactin concentrations were two times higher in EBB- compared with E-fed lambs (p < 0.05), although both were lower than in C or CBB (p < 0.001) lambs. Rectal temperatures were greater in lambs receiving dietary ergot (p ≤ 0.001) than in C- and CBB-fed lambs. In a digestibility study using eight ram lambs, treatment with BB increased neutral detergent fiber (NDF) digestibility (p = 0.01). Nitrogen retention (g) was greater (p < 0.05) for lambs receiving C or CBB compared with ergot-contaminated diets. Feces of EBB lambs had 38.5% greater (p < 0.001) recovery of alkaloids compared with those fed E. Based on sparing of prolactin, BB may reduce impacts of ergot alkaloids by increasing their excretion in feces. Accordingly, concentrations of dietary alkaloids, which would not harm sheep, would be increased by feeding BB. Full article
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12 pages, 3173 KiB  
Article
Application of Low-Fermenting Yeast Lachancea thermotolerans for the Control of Toxigenic Fungi Aspergillus parasiticus, Penicillium verrucosum and Fusarium graminearum and Their Mycotoxins
by Randa Zeidan, Zahoor Ul-Hassan, Roda Al-Thani, Virgilio Balmas and Samir Jaoua
Toxins 2018, 10(6), 242; https://doi.org/10.3390/toxins10060242 - 14 Jun 2018
Cited by 37 | Viewed by 6155
Abstract
Mycotoxins are important contaminants of food and feed. In this study, low fermenting yeast (Lachancea thermotolerans) and its derivatives were applied against toxigenic fungi and their mycotoxins. A. parasiticus, P. verrucosum and F. graminearum and their mycotoxins were exposed to [...] Read more.
Mycotoxins are important contaminants of food and feed. In this study, low fermenting yeast (Lachancea thermotolerans) and its derivatives were applied against toxigenic fungi and their mycotoxins. A. parasiticus, P. verrucosum and F. graminearum and their mycotoxins were exposed to yeast volatile organic compounds (VOCs) and cells, respectively. VOCs reduced significantly the fungal growth (up to 48%) and the sporulation and mycotoxin synthesis (up to 96%). Very interestingly, it was shown that even 7 yeast colonies reduced Fusarium’s growth and the synthesis of its mycotoxin, deoxynivalenol (DON). Moreover, decreasing yeast nutrient concentrations did not affect the inhibition of fungal growth, but reduced DON synthesis. In addition, inactivated yeast cells were able to remove up to 82% of the ochratoxin A (OTA). As an application of these findings, the potentialities of the VOCs to protect tomatoes inoculated with F. oxysporum was explored and showed that while in the presence of VOCs, no growth was observed of F. oxysporum on the inoculated surface areas of tomatoes, in the absence of VOCs, F. oxysporum infection reached up to 76% of the tomatoes’ surface areas. These results demonstrate that the application of yeasts and their derivatives in the agriculture and food industry might be considered as a very promising and safe biocontrol approach for food contamination. Full article
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14 pages, 1470 KiB  
Article
Hydrogen-Rich Water and Lactulose Protect Against Growth Suppression and Oxidative Stress in Female Piglets Fed Fusarium Toxins Contaminated Diets
by Weijiang Zheng, Xu Ji, Qing Zhang, Wenchao Du, Quanwei Wei and Wen Yao
Toxins 2018, 10(6), 228; https://doi.org/10.3390/toxins10060228 - 4 Jun 2018
Cited by 15 | Viewed by 4715
Abstract
The objective of the current experiment was to evaluate whether hydrogen-rich water (HRW) or lactulose (LAC) could protect against the adverse effects of Fusarium mycotoxins-contaminated diet on the growth performance and antioxidant status in weaning piglets. A total of 24 individually housed female [...] Read more.
The objective of the current experiment was to evaluate whether hydrogen-rich water (HRW) or lactulose (LAC) could protect against the adverse effects of Fusarium mycotoxins-contaminated diet on the growth performance and antioxidant status in weaning piglets. A total of 24 individually housed female piglets were randomly assigned to receive four treatments for 25 days (six pigs/treatment): uncontaminated basal diet (negative control), mycotoxin-contaminated (MC) diet, MC diet + HRW (MC + HRW) and MC diet + LAC (MC + LAC). The plasma hydrogen levels before and after 2 h hydrogen-free water/HRW administration were detected at day 21, and the liver hydrogen levels were detected at the end of the experiment. Serum hormones related to appetite regulation, and serum and liver oxidant and antioxidant status were also measured at the end of the experiment. Results showed that both HRW and LAC treatments significantly attenuated the reduction of average daily gain (ADG) and average daily feed intake (ADFI) caused by Fusarium mycotoxins. LAC administration increased the hydrogen concentrations in plasma and liver. HRW treated group had higher plasma hydrogen levels than the MC group. Compared with the NC group, the MC group had significantly increased serum peptide YY (PYY) and cholecystokinin (CCK) levels. Interestingly, both HRW and LAC administrations had a lower reduced serum PYY and CKK levels. Most importantly, oral administration of HRW and LAC attenuated the Fusarium mycotoxins-induced oxidative stress. In conclusion, oral administration of hydrogen-rich water or lactulose could both protect against the growth reduction and oxidative damage caused by Fusarium mycotoxins. Full article
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10 pages, 869 KiB  
Communication
Fructo-Oligosaccharide (DFA III) Feed Supplementation for Mitigation of Mycotoxin Exposure in Cattle—Clinical Evaluation by a Urinary Zearalenone Monitoring System
by Katsuki Toda, Seiichi Uno, Emiko Kokushi, Ayaka Shiiba, Hiroshi Hasunuma, Daisaku Matsumoto, Masayuki Ohtani, Osamu Yamato, Urara Shinya, Missaka Wijayagunawardane, Johanna Fink-Gremmels, Masayasu Taniguchi and Mitsuhiro Takagi
Toxins 2018, 10(6), 223; https://doi.org/10.3390/toxins10060223 - 1 Jun 2018
Cited by 9 | Viewed by 4363
Abstract
The potential effect of difructose anhydride III (DFA III) supplementation in cattle feed was evaluated using a previously developed urinary-zearalenone (ZEN) monitoring system. Japanese Black cattle from two beef herds aged 9–10 months were used. DFA III was supplemented for two weeks. ZEN [...] Read more.
The potential effect of difructose anhydride III (DFA III) supplementation in cattle feed was evaluated using a previously developed urinary-zearalenone (ZEN) monitoring system. Japanese Black cattle from two beef herds aged 9–10 months were used. DFA III was supplemented for two weeks. ZEN concentrations in feed were similar in both herds (0.27 and 0.22 mg/kg in roughage and concentrates, respectively), and below the maximum allowance in Japan. ZEN, α-zearalenol (α-ZOL), and β-ZOL concentrations in urine were measured using LC/MS/MS the day before DFA III administration, 9 and 14 days thereafter, and 9 days after supplementation ceased. Significant differences in ZEN, α-ZOL, β-ZOL, and total ZEN were recorded on different sampling dates. The concentration of inorganic phosphate in DFA III-supplemented animals was significantly higher than in controls on day 23 (8.4 vs. 7.7 mg/dL), suggesting a possible role of DFA III in tight junction of intestinal epithelial cells. This is the first evidence that DFA III reduces mycotoxin levels reaching the systemic circulation and excreted in urine. This preventive effect may involve an improved tight-junction-dependent intestinal barrier function. Additionally, our practical approach confirmed that monitoring of urinary mycotoxin is useful for evaluating the effects of dietary supplements to prevent mycotoxin adsorption. Full article
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12 pages, 1960 KiB  
Article
Removal of Zearalenone and Zearalenols from Aqueous Solutions Using Insoluble Beta-Cyclodextrin Bead Polymer
by Miklós Poór, Zelma Faisal, Afshin Zand, Tímea Bencsik, Beáta Lemli, Sándor Kunsági-Máté and Lajos Szente
Toxins 2018, 10(6), 216; https://doi.org/10.3390/toxins10060216 - 25 May 2018
Cited by 30 | Viewed by 5219
Abstract
Zearalenone (ZEN) is a Fusarium-derived mycotoxin, exerting xenoestrogenic effects in animals and humans. ZEN and its derivatives commonly occur in cereals and cereal-based products. During the biotransformation of ZEN, its reduced metabolites, α-zearalenol (α-ZEL) and β-zearalenol (β-ZEL), are formed; α-ZEL is even [...] Read more.
Zearalenone (ZEN) is a Fusarium-derived mycotoxin, exerting xenoestrogenic effects in animals and humans. ZEN and its derivatives commonly occur in cereals and cereal-based products. During the biotransformation of ZEN, its reduced metabolites, α-zearalenol (α-ZEL) and β-zearalenol (β-ZEL), are formed; α-ZEL is even more toxic than the parent compound ZEN. Since previous studies demonstrated that ZEN and ZELs form stable complexes with β-cyclodextrins, it is reasonable to hypothesize that cyclodextrin polymers may be suitable for mycotoxin removal from aqueous solutions. In this study, the extraction of ZEN and ZELs from water, buffers, and corn beer was investigated, employing insoluble β-cyclodextrin bead polymer (BBP) as a mycotoxin-binder. Our results demonstrate that even relatively small amounts of BBP can strongly decrease the mycotoxin content of aqueous solutions (including beer). After the first application of BBP for mycotoxin binding, BBP could be completely reactivated through the elimination of ZEN from the cyclodextrin cavities by washing with a 50 v/v% ethanol-water mixture. Therefore, our study suggests that insoluble cyclodextrin polymers may be suitable tools in the future to deplete mycotoxins from contaminated drinks. Full article
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16 pages, 43089 KiB  
Article
Rice Phyllosphere Bacillus Species and Their Secreted Metabolites Suppress Aspergillus flavus Growth and Aflatoxin Production In Vitro and in Maize Seeds
by Subbaiah Chalivendra, Catherine DeRobertis, Jorge Reyes Pineda, Jong Hyun Ham and Kenneth Damann
Toxins 2018, 10(4), 159; https://doi.org/10.3390/toxins10040159 - 16 Apr 2018
Cited by 8 | Viewed by 5500
Abstract
The emergence of super-toxigenic strains by recombination is a risk from an intensive use of intraspecific aflatoxin (AF) biocontrol agents (BCAs). Periodical alternation with interspecific-BCAs will be safer since they preclude recombination. We are developing an AF-biocontrol system using rice-associated Bacilli reported previously [...] Read more.
The emergence of super-toxigenic strains by recombination is a risk from an intensive use of intraspecific aflatoxin (AF) biocontrol agents (BCAs). Periodical alternation with interspecific-BCAs will be safer since they preclude recombination. We are developing an AF-biocontrol system using rice-associated Bacilli reported previously (RABs). More than 50% of RABs inhibited the growth of multiple A. flavus strains, with RAB4R being the most inhibitory and RAB1 among the least. The fungistatic activity of RAB4R is associated with the lysis of A. flavus hyphal tips. In field trails with the top five fungistatic RABs, RAB4R consistently inhibited AF contamination of maize by Tox4, a highly toxigenic A. flavus strain from Louisiana corn fields. RAB1 did not suppress A. flavus growth, but strongly inhibited AF production. Total and HPLC-fractionated lipopeptides (LPs) isolated from culture filtrates of RAB1 and RAB4R also inhibited AF accumulation. LPs were stable in vitro with little loss of activity even after autoclaving, indicating their potential field efficacy as a tank-mix application. A. flavus colonization and AF were suppressed in RAB1- or RAB4R-coated maize seeds. Since RAB4R provided both fungistatic and strong anti-mycotoxigenic activities in the laboratory and field, it can be a potent alternative to atoxigenic A. flavus strains. On the other hand, RAB1 may serve as an environmentally safe helper BCA with atoxigenic A. flavus strains, due its lack of strong fungistatic and hemolytic activities. Full article
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Jump to: Research

1 pages, 191 KiB  
Correction
Correction: Mitema, A. et al. The Development of a qPCR Assay to Measure Aspergillus flavus Biomass in Maize and the Use of a Biocontrol Strategy to Limit Aflatoxin Production. Toxins 2019, 11, 179
by Alfred Mitema, Sheila Okoth and Suhail M. Rafudeen
Toxins 2019, 11(7), 384; https://doi.org/10.3390/toxins11070384 - 1 Jul 2019
Cited by 1 | Viewed by 2729
Abstract
The authors wish to make the following correction to their paper [...] Full article
9 pages, 248 KiB  
Opinion
Biocontrol of Aspergillus and Fusarium Mycotoxins in Africa: Benefits and Limitations
by Victor Kagot, Sheila Okoth, Marthe De Boevre and Sarah De Saeger
Toxins 2019, 11(2), 109; https://doi.org/10.3390/toxins11020109 - 13 Feb 2019
Cited by 79 | Viewed by 8446
Abstract
Fungal contamination and the consequent mycotoxin production is a hindrance to food and feed safety, international trade and human and animal health. In Africa, fungal contamination by Fusarium and Aspergillus is heightened by tropical climatic conditions that create a suitable environment for pre- [...] Read more.
Fungal contamination and the consequent mycotoxin production is a hindrance to food and feed safety, international trade and human and animal health. In Africa, fungal contamination by Fusarium and Aspergillus is heightened by tropical climatic conditions that create a suitable environment for pre- and postharvest mycotoxin production. The biocontrol of Fusarium and its associated fusariotoxins has stagnated at laboratory and experimental levels with species of Trichoderma, Bacillus and atoxigenic Fusarium being tested as the most promising candidates. Hitherto, there is no impetus to upscale for field use owing to the inconsistent results of these agents. Non-aflatoxigenic strains of Aspergillus have been developed to create biocontrol formulations by outcompeting the aflatoxigenic strains, thus thwarting aflatoxins on the target produce by 70% to 90%. Questions have been raised on their ability to produce other mycotoxins like cyclopiazonic acid, to potentially exchange genetic material and to become aflatoxigenic with consequent deleterious effects on other organisms and environments. Other biocontrol approaches to mitigate aflatoxins include the use of lactic acid bacteria and yeast species which have demonstrated the ability to prevent the growth of Aspergillus flavus and consequent toxin production under laboratory conditions. Nevertheless, these strategies seem to be ineffective under field conditions. The efficacy of biological agents is normally dependent on environmental factors, formulations’ safety to non-target hosts and the ecological impact. Biocontrol agents can only be effectively evaluated after long-term use, causing a never-ending debate on the use of live organisms as a remedy to pests and diseases over the use of chemicals. Biocontrol should be used in conjunction with good agricultural practices coupled with good postharvest management to significantly reduce mycotoxins in the African continent. Full article
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