Isolation of Bacillus subtilis: screening for aflatoxins B1, M1, and G1 detoxification

Bacillus siamensis 3BS12-4 Extracellular Compounds as a Potential Biological Control Agent against Aspergillus flavus

Aspergillus flavus, the primary mold that causes food spoilage, poses significant health and economic problems worldwide. Eliminating A. flavus growth is essential to ensure the safety of agricultural products, and extracellular compounds (ECCs) produced by Bacillus spp. have been demonstrated to inhibit the growth of this pathogen. In this study, we aimed to identify microorganisms efficient at inhibiting A. flavus growth and degrading aflatoxin B1. We isolated microorganisms from soil samples using a culture medium containing coumarin (CM medium) as the sole carbon source. Of the 498 isolates grown on CM medium, only 132 bacterial strains were capable of inhibiting A. flavus growth. Isolate 3BS12-4, identified as Bacillus siamensis, exhibited the highest antifungal activity with an inhibition ratio of 43.10%, and was therefore selected for further studies. The inhibition of A. flavus by isolate 3BS12-4 was predominantly attributed to ECCs, with a minimum inhibitory concentration and minimum fungicidal concentration of 0.512 g/ml. SEM analysis revealed that the ECCs disrupted the mycelium of A. flavus. The hydrolytic enzyme activity of the ECCs was assessed by protease, β-1,3-glucanase, and chitinase activity. Our results demonstrate a remarkable 96.11% aflatoxin B1 degradation mediated by ECCs produced by isolate 3BS12-4. Furthermore, treatment with these compounds resulted in a significant 97.93% inhibition of A. flavus growth on peanut seeds. These findings collectively present B. siamensis 3BS12-4 as a promising tool for developing environmentally friendly products to manage aflatoxin-producing fungi and contribute to the enhancement of agricultural product safety and food security.

Rice Weevil (Sitophilus oryzae L.) Gut Bacteria Inhibit Growth of Aspergillus flavus and Degrade Aflatoxin B1

In this study, bacteria residing in the gut of the rice weevils (Sitophilus oryzae L.) (Coleoptera: Curculionidae) feeding on aflatoxin-contaminated corn kernels were isolated and evaluated for their ability to suppress Aspergillus flavus and to remove/degrade aflatoxin B1 (AFB1). Four morphologically distinct S. oryzae gut-associated bacterial isolates were isolated and identified as Bacillus subtilis (RWGB1), Bacillus oceanisediminis (RWGB2), Bacillus firmus (RWGB3), and Pseudomonas aeruginosa (RWGB4) based on 16S rRNA gene sequence analysis. These bacterial isolates inhibited A. flavus growth in the dual culture assay and induced morphological deformities in the fungal hyphae, as confirmed by scanning electron microscopy. All four bacterial isolates were capable of removing AFB1 from the nutrient broth medium. In addition, culture supernatants of these bacterial isolates degraded AFB1, and the degradation of toxin molecules was confirmed by liquid chromatography-mass spectrometry. The bacterial isolates, B. subtilis RWGB1, B. oceanisediminis RWGB2, and P. aeruginosa RWGB4, were capable of producing antifungal volatile organic compounds that inhibited A. flavus growth. These results suggest that the bacterial isolates from S. oryzae gut have the potential to bind and/or degrade AFB1. Further research on their application in the food and feed industries could enhance the safety of food and feed production.

Relevant mycotoxins in oil crops, vegetable oils, de-oiled cake and meals: Occurrence, control, and recent advances in elimination

Mycotoxins in agricultural commodities have always been a concern due to their negative impacts on human and livestock health. Issues associated with quality control, hot and humid climate, improper storage, and inappropriate production can support the development of fungus, causing oil crops to suffer from mycotoxin contamination, which in turn migrates to the resulting oil, de-oiled cake and meals during the oil processing. Related research which supports the development of multi-mycotoxin prevention programs has resulted in satisfactory mitigation effects, mainly in the pre-harvest stage. Nevertheless, preventive actions are unlikely to avoid the occurrence of mycotoxins completely, so removal strategies may still be necessary to protect consumers. Elimination of mycotoxin has been achieved broadly through the physical, biological, or chemical course. In view of the steadily increasing volume of scientific literature regarding mycotoxins, there is a need for ongoing integrated knowledge systems. This work revisited the knowledge of mycotoxins affecting oilseeds, food oils, cake, and meals, focusing more on their varieties, toxicity, and preventive strategies, including the methods adopted in the decontamination, which supplement the available information.

Mechanisms by which microbial enzymes degrade four mycotoxins and application in animal production: A review

Mycotoxins are toxic compounds that pose a serious threat to animal health and food safety. Therefore, there is an urgent need for safe and efficient methods of detoxifying mycotoxins. As biotechnology has continued to develop, methods involving biological enzymes have shown great promise. Biological enzymatic methods, which can fundamentally destroy the structures of mycotoxins and produce degradation products whose toxicity is greatly reduced, are generally more specific, efficient, and environmentally friendly. Mycotoxin-degrading enzymes can thus facilitate the safe and effective detoxification of mycotoxins which gives them a huge advantage over other methods. This article summarizes the newly discovered degrading enzymes that can degrade four common mycotoxins (aflatoxins, zearalenone, deoxynivalenol, and ochratoxin A) in the past five years, and reveals the degradation mechanism of degrading enzymes on four mycotoxins, as well as their positive effects on animal production. This review will provide a theoretical basis for the safe treatment of mycotoxins by using biological enzyme technology.

Biotechnological and Biocontrol Approaches for Mitigating Postharvest Diseases Caused by Fungal Pathogens and Their Mycotoxins in Fruits: A Review

Postharvest diseases caused by fungal pathogens are significant contributors to the postharvest losses of fruits. Moreover, some fungal pathogens produce mycotoxins, which further compromise the safety and quality of fruits. In this review, the potential of biotechnological and biocontrol approaches for mitigating postharvest diseases and mycotoxins in fruits is explored. The review begins by discussing the impact of postharvest diseases on fruit quality and postharvest losses. Next, it provides an overview of major postharvest diseases caused by fungal pathogens. Subsequently, it delves into the role of biotechnological approaches in controlling these diseases. The review also explored the application of biocontrol agents, such as antagonistic yeasts, bacteria, and fungi, which can suppress pathogen growth. Furthermore, future trends and challenges in these two approaches are discussed in detail. Overall, this review can provide insights into promising biotechnological and biocontrol strategies for managing postharvest diseases and mycotoxins in fruits.

Aflatoxin B1 and ochratoxin A reduction by Lactobacillus spp. during bread making

BACKGROUND

Aflatoxin B1 (AFB1) and ochratoxin A (OTA) are among the most important mycotoxins with common presence in bread and bakery products. Biological detoxification of mould food spoilage and mycotoxin contamination by lactic acid bacteria (LABs) exhibits high potential on a cost-effective and large scale. In this work, the effect of Lactobacillus strains isolated from goat milk whey on reducing AFB1 and OTA during bread making was evaluated by the determination of mycotoxin reduction potential of 12 LAB strains after 72 h incubation in De Man-Rogosa-Sharpe (MRS) broth (37 °C). The most effective LABs were lyophilized and added as ingredient in bread formulation, analysing mycotoxins by high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry after bread fermentation and baking.

RESULTS

AFB1 was reduced in MRS broth by seven LABs (11-35%), highlighting Lactobacillus plantarum B3 activity; while all LABs reduced OTA (12-40%) with L. plantarum B3 and Lactobacillus paracasei B10 as the most active strains. Both LABs were lyophilized and added in contaminated bread with and without yeast, reaching AFB1 and OTA reductions up to 27% and 32% respectively in dough and up to 55% and 34% respectively in bread.

CONCLUSION

The selected strains significantly reduced AFB1 and OTA during bread fermentation, pointing to a potential biocontrol strategy for mycotoxins detoxification in bread and bakery products. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Auricularia auricular Adsorbs Aflatoxin B1 and Ameliorates Aflatoxin B1-Induced Liver Damage in Sprague Dawley Rats

Aflatoxin B1 (AFB1), as a class I carcinogen, poses a substantial health risk to individuals. Contamination of food sources, particularly grains and nuts, with Aspergillus flavus (A. flavus) contributes to the prevalence of AFB1. The impact of global warming has spurred research into the development of AFB1 prevention technologies. While edible fungi have shown potential in detoxifying AFB1, there is a scarcity of literature on the application of Auricularia auricular (A. auricular) in this context. This study aimed to investigate the ability and underlying mechanism of A. auricular mycelia to adsorb aflatoxin B1, as well as evaluate its protective effects on the AFB1-induced liver damage in SD rats. Additionally, the effects of temperature, time, pH, and reaction ratio on the adsorption rate were examined. Combining thermodynamic and kinetic data, the adsorption process was characterized as a complex mechanism primarily driven by chemical adsorption. In SD rats, the A. auricular mycelia exhibited alleviation of AFB1-induced liver damage. The protective effects on the liver attributed to A. auricular mycelia may involve a reduction in AFB1 adsorption in the intestine, mitigation of oxidative stress, and augmentation of second-phase detoxification enzyme activity. The adsorption method for AFB1 not only ensures safety and non-toxicity, but also represents a dietary regulation strategy for achieving effective defense against AFB1.

Detoxification impacts of dietary probiotic and prebiotic supplements against aflatoxins: an updated knowledge

The widespread prevalence of food pollutants seriously threatens human and animal health. Mycotoxins are secondary metabolites primarily formed by toxigenic fungal genera, including Aspergillus, Penicillium, Fusarium, and Alternaria, demonstrating one of the principal pollutants in diets or feed products. Mycotoxin contamination in food can harm health, including stunted development, immune system suppression, infertility, vomiting, and gastrointestinal and cancerous conditions. These effects can occur both acutely and chronically. The complex food chain can be contaminated with mycotoxins at any point, including during harvest, industrial processing, shipping, or storage, putting the food sector under societal pressure owing to the waste generated by infected goods. One of the biological controls of mycotoxin is provided by probiotics and prebiotics, controlled as foods and dietary supplements made of bacteria or yeast. Aflatoxin's bioavailability and gastrointestinal absorption can be reduced using various probiotics and prebiotics.

Characteristics of Aflatoxin B1 Degradation by Stenotrophomonas acidaminiphila and It's Combination with Black Soldier Fly Larvae

Aflatoxin B₁ (AFB₁) is a common mycotoxin contaminant in cereals that causes severe economic losses and serious risks to the health of humans and animals. In this paper, we investigated the characteristics of AFB₁ degradation by black soldier fly larvae (BSFL) combined with commensal intestinal microorganisms. Germ-free BSFL and non-sterile BSFL were reared on peanut meal spiked with AFB₁ for 10 days. The result showed that germ-free BSFL and non-sterile BSFL could achieve 31.71% and 88.72% AFB₁ degradation, respectively, which indicated the important role of larvae gut microbiota in AFB₁ degradation. Furthermore, twenty-five AFB₁-degrading bacteria were isolated from BSFL gut, and S. acidaminiphila A2 achieved the highest AFB₁ degradation, by 94%. When S. acidaminiphila A2 was re-inoculated to BSFL, the detrimental effect of AFB₁ on the growth performance of BSFL was alleviated, and complete AFB₁ degradation in peanut meal was obtained. In conclusion, the present study may provide a strategy to degrade AFB₁ in feedstuff through bioconversion with BSFL in combination with gut-originated AFB₁-degrading bacteria, while providing a sustainable insect protein and fat source to animals.

Efficacy of the antifungal metabolites of Streptomyces philanthi RL-1-178 on aflatoxin degradation with its application to prevent aflatoxigenic fungi in stored maize grains and identification of the bioactive compound

Aflatoxin B₁ is a potent carcinogen produced by Aspergillus flavus (A. flavus) and Aspergillus. parasiticus (A. parasiticus), mainly during grain storage. The efficacy of the freeze-dried culture filtrate of Streptomyces philanthi (S. philanthi) strain RL-1-178 (DCF) on degradation of aflatoxin B₁ (AFB₁) were evaluated and its bioactive compounds were identified. The DCF at a concentration of 9.0% (w/v) completely inhibited growth and AFB₁ production of A. parasiticus TISTR 3276 and A. flavus PSRDC-4 after 7 days tested in yeast-extract sucrose (YES) medium and on stored maize grains after 28 and 14 days incubation, respectively. This indicated the more tolerance of A. parasiticus over A. flavus. The DCF and bacterial cells of S. philanthi were capable to degrade AFB₁ by 85.0% and 100% for 72 h and 8 days, respectively. This confirmed the higher efficacy of the DCF over the cells. After separation of the DCF on thin-layer chromatography (TLC) plate by bioautography bioassay, each active band was identified by liquid chromatography-quadrupole time of flight mass spectrometer (LC-Q-TOF MS/MS). The results revealed two compounds which were identified as azithromycin and an unknown based on mass ions of both ESI⁺ and ESI^- modes. The antifungal metabolites in the culture filtrate of S. philanthi were proved to degrade aflatoxin B₁. It could be concluded that the DCF may be applied to prevent the growth of the two aflatoxin-producing fungi as well as the occurrence of aflatoxin in the stored maize grains.

Effect of Bacillus Additives on Fermentation Quality and Bacterial Community during the Ensiling Process of Whole-Plant Corn Silage

The aim of this study was to evaluate the effects of a complex Bacillus subtilis additive on the fermentation quality and bacterial community during the ensiling process of whole-plant corn silage (WPCS). The pH values of WPCS treated with the B. subtilis inoculant decreased faster than those of the control without inoculant, and significantly higher contents of lactic acid (LA) and acetic acid (AA) were observed. After 45 days of ensiling, the LA contents reached 7.95% (w/w). In the treatment group, the neutral detergent fibre (NDF) and acid detergent fibre (ADF) contents decreased significantly compared to the control, and the degradation rates of the NDF and ADF were 26.52% and 27.34% after 45 days, respectively. The deoxynivalenol (DON) content in the treatment group decreased to 205.67 μg/kg, which was significantly lower than the content of 382.51 μg/kg in the control group. The results indicated the positive effect of the B. subtilis inoculant in improving WPCS fermentation, especially in terms of degrading linocellulose and removing DON. The analysis of the bacterial community indicated that the B. subtilis inoculant resulted in an increased abundance of Lactobacillus, which contributed to the enhancement of LA production. The increased abundance of Bacillus possibly played a role in the degradation of NDF and ADF and the reduction in DON. Therefore, the complex B. subtilis additive could be used for the production of high-quality WPCS.

Molecular assessment of microbial diversity on eggshell of chukar partridges (Alectoris chukar) under semi-captive conditions

Due to human activity, climatic changes and habitat damage, the Chukar partridge (Alectoris chukar) is experiencing a population decrease. The goal of this work was to isolate and identify the inner eggshell microflora in order to learn more about their function in A. chukar embryo mortality and hatchability in semi-captive settings. During the egg-laying season, 204 eggs were gathered from the Balkasar Research Complex in Chakwal, Pakistan. These eggshells were divided into four categories after incubation: un-pricked with dead embryo, pricked with dead embryo, hatched, and unfertilized eggs. A total of 47 (23.03%) samples tested positive for gram-positive bacteria, which were then identified using 16S rRNA sequence analysis. Bacillus subtilis, Bacillus cereus, Bacillus amyloliquefaciens, Bacillus toyonensis, Bacillus thuringiensis and Staphylococcus sciuri were among the identified species. Hatched eggshells had the highest percentage of bacterial flora (36.17%), followed by un-pricked with dead embryo (23.40%) and pricked with death embryo (21.27%), and unfertilized eggshells had the lowest percentage (19.14%). As a result, the findings of this study revealed that microbial contamination of eggshells could be a cause of early embryonic stage degeneration and bird death.

Invited review: Remediation strategies for mycotoxin control in feed

Mycotoxins are secondary metabolites of different species of fungi. Aflatoxin B1 (AFB1), deoxynivalenol (DON), zearalenone (ZEN) and fumonisin B1 (FB1) are the main mycotoxins contaminating animal feedstuffs. These mycotoxins can primarily induce hepatotoxicity, immunotoxicity, neurotoxicity and nephrotoxicity, consequently cause adverse effects on the health and performance of animals. Therefore, physical, chemical, biological and nutritional regulation approaches have been developed as primary strategies for the decontamination and detoxification of these mycotoxins in the feed industry. Meanwhile, each of these techniques has its drawbacks, including inefficient, costly, or impractically applied on large scale. This review summarized the advantages and disadvantages of the different remediation strategies, as well as updates of the research progress of these strategies for AFB1, DON, ZEN and FB1 control in the feed industry.

Protective Effects of Bacillus subtilis ANSB060, Bacillus subtilis ANSB01G, and Devosia sp. ANSB714-Based Mycotoxin Biodegradation Agent on Mice Fed with Naturally moldy Diets

Mycotoxins are toxic secondary metabolites produced by toxigenic fungi that commonly contaminate agricultural crops. The purpose of the current study was to evaluate whether Bacillus subtilis ANSB060, Bacillus subtilis ANSB01G, and Devosia sp. ANSB714-based mycotoxin biodegradation agent (MBA) could alleviate the negative effects of naturally moldy diet containing aflatoxin (AF), zearalenone (ZEN), and deoxynivalenol (DON) on growth performance, serum immune function, and antioxidant capacity as well as tissue residues in mice. A total of 54 mice were randomly divided into three dietary treatments: basal diet (CON), multi-mycotoxins contaminated diet (MCD) containing AF, ZEN and DON and multi-mycotoxins contaminated diet plus MBA at a dose of 1.0 g kg^-1 feed (MCD + MBA). Mice fed with moldy diet showed a significant decrease in body weight gain (p < 0.05), whereas the relative weight of the liver, spleen and uterus were remarkably increased (p < 0.05). Serum IgA and IgM contents were significantly decreased in MCD treatment compared with that in CON treatment (p < 0.05). In contrast, serum interleukin-1β (IL-1β), interleukin-2 (IL-2), and interleukin-6 (IL-6) concentrations were significantly promoted in mice fed with moldy diet (p < 0.05). Besides, the exposure to mycotoxins caused marked down-regulation of serum superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities in mice (p < 0.05). The addition of MBA effectively counteracted these toxic effects of moldy diet on mice. And DON residues in kidneys of mice consuming moldy diet were eliminated by the supplementation with MBA. Taken together, Bacillus subtilis ANSB060, Bacillus subtilis ANSB01G, and Devosia sp. ANSB714-based mycotoxin biodegradation agent has great potential use as a microbial additive to counteract mycotoxins contamination in food and feed.

Enzymatic Degradation of Multiple Major Mycotoxins by Dye-Decolorizing Peroxidase from Bacillus subtilis

The co-occurrence of multiple mycotoxins, including aflatoxin B₁ (AFB₁), zearalenone (ZEN) and deoxynivalenol (DON), widely exists in cereal-based animal feed and food. At present, most reported mycotoxins degrading enzymes target only a certain type of mycotoxins. Therefore, it is of great significance for mining enzymes involved in the simultaneous degradation of different types of mycotoxins. In this study, a dye-decolorizing peroxidase-encoding gene BsDyP from Bacillus subtilis SCK6 was cloned and expressed in Escherichia coli BL21/pG-Tf2. The purified recombinant BsDyP was capable of oxidizing various substrates, including lignin phenolic model compounds 2,6-dimethylphenol and guaiacol, the substrate 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid), anthraquinone dye reactive blue 19 and azo dye reactive black 5, as well as Mn²⁺. In addition, BsDyP could efficiently degrade different types of mycotoxins, including AFB₁, ZEN and DON, in presence of Mn²⁺. More important, the toxicities of their corresponding enzymatic degradation products AFB₁-diol, 15-OH-ZEN and C₁₅H₁₈O₈ were significantly lower than AFB₁, ZEN and DON. In summary, these results proved that BsDyP was a promising candidate for the simultaneous degradation of multiple mycotoxins in animal feed and food.

Effects of compound probiotics and aflatoxin-degradation enzyme on alleviating aflatoxin-induced cytotoxicity in chicken embryo primary intestinal epithelium, liver and kidney cells

Aflatoxin B₁ (AFB₁) is one of the most dangerous mycotoxins for humans and animals. This study aimed to investigate the effects of compound probiotics (CP), CP supernatant (CPS), AFB₁-degradation enzyme (ADE) on chicken embryo primary intestinal epithelium, liver and kidney cell viabilities, and to determine the functions of CP + ADE (CPADE) or CPS + ADE (CPSADE) for alleviating cytotoxicity induced by AFB₁. The results showed that AFB₁ decreased cell viabilities in dose-dependent and time-dependent manners. The optimal AFB₁ concentrations and reactive time for establishing cell damage models were 200 µg/L AFB₁ and 12 h for intestinal epithelium cells, 40 µg/L and 12 h for liver and kidney cells. Cell viabilities reached 231.58% (p < 0.05) for intestinal epithelium cells with CP addition, 105.29% and 115.84% (p < 0.05) for kidney and liver cells with CPS additions. The further results showed that intestinal epithelium, liver and kidney cell viabilities were significantly decreased to 87.12%, 88.7% and 84.19% (p < 0.05) when the cells were exposed to AFB₁; however, they were increased to 93.49% by CPADE addition, 102.33% and 94.71% by CPSADE additions (p < 0.05). The relative mRNA abundances of IL-6, IL-8, TNF-α, iNOS, NF-κB, NOD1 (except liver cell) and TLR2 in three kinds of primary cells were significantly down-regulated by CPADE or CPSADE addition, compared with single AFB₁ group (p < 0.05), indicating that CPADE or CPSADE addition could alleviate cell cytotoxicity and inflammation induced by AFB₁ exposure through suppressing the activations of NF-κB, iNOS, NOD1 and TLR2 pathways.

Biological Control and Mitigation of Aflatoxin Contamination in Commodities

Aflatoxins (AFs) are toxic secondary metabolites produced mostly by Aspergillus species. AF contamination entering the feed and food chain has been a crucial long-term issue for veterinarians, medicals, agroindustry experts, and researchers working in this field. Although different (physical, chemical, and biological) technologies have been developed, tested, and employed to mitigate the detrimental effects of mycotoxins, including AFs, universal methods are still not available to reduce AF levels in feed and food in the last decades. Possible biological control by bacteria, yeasts, and fungi, their excretes, the role of the ruminal degradation, pre-harvest biocontrol by competitive exclusion or biofungicides, and post-harvest technologies and practices based on biological agents currently used to alleviate the toxic effects of AFs are collected in this review. Pre-harvest biocontrol technologies can give us the greatest opportunity to reduce AF production on the spot. Together with post-harvest applications of bacteria or fungal cultures, these technologies can help us strictly reduce AF contamination without synthetic chemicals.

Aflatoxin Detoxification Using Microorganisms and Enzymes

Mycotoxin contamination causes significant economic loss to food and feed industries and seriously threatens human health. Aflatoxins (AFs) are one of the most harmful mycotoxins, which are produced by Aspergillus flavus, Aspergillus parasiticus, and other fungi that are commonly found in the production and preservation of grain and feed. AFs can cause harm to animal and human health due to their toxic (carcinogenic, teratogenic, and mutagenic) effects. How to remove AF has become a major problem: biological methods cause no contamination, have high specificity, and work at high temperature, affording environmental protection. In the present research, microorganisms with detoxification effects researched in recent years are reviewed, the detoxification mechanism of microbes on AFs, the safety of degrading enzymes and reaction products formed in the degradation process, and the application of microorganisms as detoxification strategies for AFs were investigated. One of the main aims of the work is to provide a reliable reference strategy for biological detoxification of AFs.

Novel strategies for degradation of aflatoxins in food and feed: A review

Aflatoxins are toxic secondary metabolites mainly produced by Aspergillus fungi, posing high carcinogenic potency in humans and animals. Dietary exposure to aflatoxins is a global problem in both developed and developing countries especially where there is poor regulation of their levels in food and feed. Thus, academics have been striving over the decades to develop effective strategies for degrading aflatoxins in food and feed. These strategies are technologically diverse and based on physical, chemical, or biological principles. This review summarizes the recent progress on novel aflatoxin degradation strategies including irradiation, cold plasma, ozone, electrolyzed oxidizing water, organic acids, natural plant extracts, microorganisms and enzymes. A clear understanding of the detoxification efficiency, mechanism of action, degradation products, application potential and current limitations of these methods is presented. In addition, the development and future perspective of nanozymes in aflatoxins degradation are introduced.

Toxin Degradation by Rumen Microorganisms: A Review

Animal feeds may contain exogenous compounds that can induce toxicity when ruminants ingest them. These toxins are secondary metabolites originating from various sources including plants, bacteria, algae and fungi. Animal feed toxins are responsible for various animal poisonings which negatively impact the livestock industry. Poisoning is more frequently reported in newly exposed, naïve ruminants while ‘experienced’ ruminants are observed to better tolerate toxin-contaminated feed. Ruminants can possess detoxification ability through rumen microorganisms with the rumen microbiome able to adapt to utilise toxic secondary metabolites. The ability of rumen microorganisms to metabolise these toxins has been used as a basis for the development of preventative probiotics to confer resistance against the poisoning to naïve ruminants. In this review, detoxification of various toxins, which include plant toxins, cyanobacteria toxins and plant-associated fungal mycotoxins, by rumen microorganisms is discussed. The review will include clinical studies of the animal poisoning caused by these toxins, the toxin mechanism of action, toxin degradation by rumen microorganisms, reported and hypothesised detoxification mechanisms and identified toxin metabolites with their toxicity compared to their parent toxin. This review highlights the commercial potential of rumen inoculum derived probiotics as viable means of improving ruminant health and production.

Anti-mycotoxigenic properties of probiotic Bacillus spp. in Japanese quails

The current study was conducted to evaluate the anti-mycotoxigenic effects of previously isolated Bacillus spp. in Japanese quails. A total of 240-day-old Japanese quails were assigned in to six treatments and four replicates. Dietary treatments included the following: negative control (basal diet), positive control (basal diet + 2.5 ppm afltatoxin B₁), probiotic treatments (basal diet + 2.5 ppm afltatoxin B₁), and 10⁸ cfu/ml of different Bacillus spp. (B. megaterium, B. subtilis, or B. laterosporus) in drinking water and treatment P (basal diet + 2.5 ppm afltatoxin B₁ and 2.5 ppm Polysorb®). Body weight gain, feed intake, and feed conversion ratio were not affected by dietary treatments (P > 0.05). Carcass yield significantly increased in B. megaterium and B. subtilis treatments compared with positive control. Supplementation of B. megaterium significantly increased testes, uterus and oviduct weights, skin response to 2,4-dinitro 1-chlorobenzene and phytohemagglutinin, and antibody production against sheep red blood cells (P < 0.05). B. megaterium could significantly increase bursa weight and decrease liver weight compared with positive control (P < 0.05). B. megaterium, B. laterosporus, and Polysorb treatments significantly decreased H:L and aspartate aminotransferase activity in aflatoxin B₁ fed control (P < 0.05). B. megaterium and B. laterosporus significantly increased tibia weight, length, radius, index, and ash content compared with positive control (P < 0.05). All dietary additives significantly reduced meat oxidation, total aerobic bacteria, and spore forming bacteria of ileal content compared with positive control (P < 0.05). Ileal lactic acid bacteria significantly increased in B. megaterium treatment (P < 0.05). Totally, B. megaterium might be a promising probiotic with a comparable afltatoxin B₁ removal potential to commercial toxin binder (Polysorb).

Biodegradation of aflatoxin B1 with cell-free extracts of Trametes versicolor and Bacillus subtilis

Aflatoxin B₁ (AFB₁) is one of the most common contaminants of poultry feed and has been linked to adverse effects on animal health and productivity. In this study, the degradation of AFB₁ was studied with cell-free extracts (CFE) of Trametes versicolor and Bacillus subtilis using High-Performance Liquid chromatography (HPLC). CFE from B. subtilis and T. versicolor gave 60% and 34% of AFB₁ degradation respectively, while heat-inactivated extracts showed no degradation. By-products obtained at the end of AFB₁ degradation were analyzed by Liquid Chromatography with tandem mass spectrometry (LC-MS/MS). After 96 h of incubation, by-products with lower m/z values were obtained with CFE from B. subtilis as compared to that from T. versicolor, indicating a higher degradation efficiency of the former. Additionally, the detection of a by-product which could correspond to AFB1-8,9 dihydrodiol - a less toxic derivative of AFB₁ - after 72 and 96 h of incubation with CFE from B. subtilis, could indicate the simultaneous detoxification along with degradation of AFB₁ by B. subtilis CFE.

Aflatoxin B1-degrading activity from Bacillus subtilis BCC 42005 isolated from fermented cereal products

Aflatoxin B₁ is a naturally occurring mycotoxin that is produced as secondary metabolite by Aspergillus spp., especially A. flavus and A. parasiticus. This is the most severe toxin due to its carcinogenic, mutagenic, and teratogenic properties. Hence, methods for toxin degradation have been received increasing interest from both scientific communities and industries. In this study, 32 isolates of Bacillus spp. from various fermented cereal products were screened for their aflatoxin B₁ degradation ability. The results indicated the extracellular fraction of Bacillus subtilis BCC 42005 isolated from Iru (African locust bean) potentially possessed aflatoxin B₁-degrading ability. The maximum activity of the active fraction was at 50°C and pH 8.0. The activity was stable in a wide range of pH (5.0-8.0) and temperature (25-60°C). The aflatoxin B₁-degrading mechanisms of this strain may be possibly involved by enzyme(s). This extracellular fraction was not toxic at IC₅₀ 4 mg/ml and it can be combined with water as a soaking agent for maize, which results in 54% of aflatoxin B₁ reduction after contact time 120 min. Hence, the extracellular fraction of Bacillus subtilis BCC 42005 can be further applied as an effective soaking agent in a pretreatment process with a practical and easy-to-implement condition and also probably used to reduce the aflatoxin B₁ contamination in other foods and feeds commodities.

Microbiological Detoxification of Mycotoxins: Focus on Mechanisms and Advances

Some fungal species of the genera Aspergillus, Penicillium, and Fusarium secretes toxic metabolites known as mycotoxins, have become a global concern that is toxic to different species of animals and humans. Biological mycotoxins detoxification has been studied by researchers around the world as a new strategy for mycotoxin removal. Bacteria, fungi, yeast, molds, and protozoa are the main living organisms appropriate for the mycotoxin detoxification. Enzymatic and degradation sorptions are the main mechanisms involved in microbiological detoxification of mycotoxins. Regardless of the method used, proper management tools that consist of before-harvest prevention and after-harvest detoxification are required. Here, in this review, we focus on the microbiological detoxification and mechanisms involved in the decontamination of mycotoxins.

Effects of three Bacillus specious on hatchability, growth performance and serum biochemistry in Japanese quails fed diet contaminated with Aflatoxin B1

 In total, 240 one-day–old Japanese quails (Coturnix Coturnix Japonica) allocated at random to 6 treatments with 4 replicates and 10 birds in each. Treatments used were: 1) Negative control (without any additives or AFB1); 2) Positive control (basal diet + 2.5 ppm AFB1; 2); 3) TA008 (positive control + 108 cfu/ml Bacillus. megaterium TA008); 4) TA049 (positive control + 108 cfu mL-1 Bacillus. subtilis TA049); 5) TA010 (positive control+ 108 cfu mL-1 Brevibacillus brevis TA010) and 6) P (positive control + 2.5 g kg-1 Polysorb® in feed). Hatchability and embryonic mortality were significantly influenced by additives and AFB1 (p < 0.05). Birds fed TA008 improved 12 % hatchability and reduced 10 % embryonic mortality in compared to positive control (p < 0.05). Weight gain and feed conversion ratio did not affected by treatments (p > 0.05). Feed intake was significantly improved in birds feeding by TA008 at 0-21 days (p < 0.05). There were significant differences on relative weights of carcass, gizzard and proventriculus among treatments (p < 0.05). Serum total protein, albumin, cholesterol, glucose, HDL, globulin and uric acid were significantly affected by treatments (p < 0.05). These results showed that the inclusion of bacillus megaterium as potential probiotic into contaminated diets could improve the adverse effects of AFB1 in Japanese quails.

Degradation of Aflatoxin B1 by a Sustainable Enzymatic Extract from Spent Mushroom Substrate of Pleurotus eryngii

Ligninolytic enzymes from white-rot fungi, such as laccase (Lac) and Mn-peroxidase (MnP), are able to degrade aflatoxin B₁ (AFB1), the most harmful among the known mycotoxins. The high cost of purification of these enzymes has limited their implementation into practical technologies. Every year, tons of spent mushroom substrate (SMS) are produced as a by-product of edible mushroom cultivation, such as Pleurotus spp., and disposed at a cost for farmers. SMS may still bea source of ligninolytic enzymes useful for AFB1 degradation. The in vitro AFB1-degradative activity of an SMS crude extract (SMSE) was investigated. Results show that: (1) in SMSE, high Lac activity (4 U g⁻¹ dry matter) and low MnP activity (0.4 U g⁻¹ dry matter) were present; (2) after 1 d of incubation at 25 °C, the SMSE was able to degrade more than 50% of AFB1, whereas after 3 and 7 d of incubation, the percentage of degradation reached the values of 75% and 90%, respectively; (3) with increasing pH values, the degradation percentage increased, reaching 90% after 3 d at pH 8. Based on these results, SMS proved to be a suitable source of AFB1 degrading enzymes and the use of SMSE to detoxify AFB1 contaminated commodities appears conceivable.

Investigation and Characterization of Myroides odoratimimus Strain 3J2MO Aflatoxin B1 Degradation

Aflatoxin B₁ (AFB₁), is a type I carcinogen that is one of the strongest naturally occurring aflatoxins and can be injurious to humans and livestock upon ingestion, inhalation, or skin contact, with carcinogenic and mutagenic effects. It causes significant hazardous effects to the food- and animal-production industries. We found a bacterial strain, 3J2MO, that degraded AFB₁ well, and here we tested and characterized its AFB₁-degradation ability. The strain degraded about 93.82% of the AFB₁ after incubation for 48 h in Luria-Bertani (LB) medium at 37 °C with a final concentration of 100 ppb and an inoculation quantity of 1 × 10⁷ cfu/mL. High-performance liquid chromatography-fluorescence detection (HPLC-FLD) was used to determine AFB₁ amounts. The maximum degradation rates were 89.23% at pH 8.5; 55.78% at an inoculation quantity of 1 × 10⁸ cfu/mL; and 71.50 and 71.21% at 34 and 37 °C, respectively. Treatment with sucrose and soluble starch as carbon sources and beef extract and ammonium acetate as nitrogen sources stimulated the degradation rate. Mg²⁺ and Ca²⁺ ions were activators for AFB₁ degradation; however, Mn²⁺, Fe³⁺, Zn²⁺, and Cu²⁺ were strong inhibitors. This bacterial strain has potential in bioremediation and the detoxification of aflatoxin contamination for biocontrol strategies in both agricultural products and food-industry matrices.

Efficacy of Bacillus subtilis ANSB060 Biodegradation Product for the Reduction of the Milk Aflatoxin M₁ Content of Dairy Cows Exposed to Aflatoxin B₁

This study was conducted to determine the effect of Bacillus subtilis ANSB060 biodegradation product (BDP) in reducing the milk aflatoxin M₁ (AFM₁) content of dairy cows fed a diet contaminated with aflatoxin B₁ (AFB₁). Twenty-four Chinese Holstein cows (254 ± 19 d in milk; milk production 19.0 ± 1.2 kg d⁻¹) were assigned to three dietary treatments, as follows: (1) control diet (CON), consisting of a basal total mixed ration (TMR); (2) aflatoxin diet (AF), containing CON plus 63 μg of AFB₁ kg⁻¹ of diet dry matter; and (3) aflatoxin diet plus BDP (AF + BDP), containing AF plus BDP at 0.2% of diet dry matter. The experiment lasted 12 days, including an AFB₁-dosing period from days one to eight, followed by a clearance period from days nine to twelve. Milk samples were collected on days 2, 4, 6, and 8–12, and the plasma was sampled on day 9, before morning feeding. Short-term AFB₁ exposure did not affect the milk production and composition. The plasma biochemical indices, except for lactic dehydrogenase (LDH), were also not changed by the AFB₁ intake. The plasma LDH level was significantly elevated (p < 0.05) following dietary treatment with AFB₁, while no significant difference was observed between the AF + BDP and CON treatments. Adding BDP to the AFB₁-contaminaed diet resulted in a significant reduction in AFM₁ concentration (483 vs. 665 ng L⁻¹) in the milk, AFM₁ excretion (9.14 vs. 12.71 μg d⁻¹), and transfer rate of dietary AFB₁ to milk AFM₁ (0.76 vs. 1.06%). In conclusion, the addition of BDP could be an alternative method for reducing the dietary AFB₁ bioavailability in dairy cows.

Effect of Compound Probiotics and Mycotoxin Degradation Enzymes on Alleviating Cytotoxicity of Swine Jejunal Epithelial Cells Induced by Aflatoxin B₁ and Zearalenone

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.

Presence of aiiA homologue genes encoding for N-Acyl homoserine lactone-degrading enzyme in aflatoxin B1-decontaminating Bacillus strains with potential use as feed additives

Microbial degradation of aflatoxins (AFs) is an alternative to the use of mycotoxin binders. The lactone ring is a possible target for microbial enzymes and its cleavage reduces AFs toxicity. The aim of this study was to isolate and identify Bacillus strains able to degrade AFB₁ to less toxic metabolites and to identify aiiA genes encoding for N-acyl-homoserine lactone (AHL) lactonase to possibly correlate detoxification with the production of this enzyme. Eleven soilborne Bacillus strains were isolated and identified by MALDI-TOF MS. Ten cultures and eight cell free culture supernatants (CFCS) were able to significantly (P < 0.05) degrade 27.78-79.78% AFB₁. Cell lysates were also able to degrade AFB₁ (P < 0.05). Exposure to 70 and 80 °C did not affect enzyme activity. Aflatoxin B₁ toxicity towards Artemia salina was reduced after degradation by each of the Bacillus strains. B. subtilis RC1B, B. cereus RC1C and B. mojavensis RC3B, amplified a fragment of 753 pb corresponding to the aiiA gene encoding for AHL lactonase. AFB₁ degradation by the strains tested was due to the extracellular and intracellular enzymes. If demonstrated to be safe, these could be used to detoxify AFB₁ in contaminated food or feed.

Effect of the combined compound probiotics with mycotoxin-degradation enzyme on detoxifying aflatoxin B1 and zearalenone

Aflatoxin B₁ (AFB₁) and zearalenone (ZEA) are the secondary toxic metabolites of fungi which contaminate a wide range of food and feedstuffs. Limiting exposure of humans and livestock to them is very essential. Among numerous methods of mycotoxin-degradation, biodegradation by microorganisms and enzymes is an effective and promising approach to eliminate their hazards. The present study aims to optimize the proportion of different species of beneficial microbes by means of response surface methodology (RSM) and its combination with mycotoxin-degradation enzymes. The results indicated that AFB₁ and ZEA degradation rates were 38.38% and 42.18% by individual Bacillus subtilis (P < 0.05); however, AFB₁ and ZEA degradation rates reached 45.49% and 44.90% (P < 0.05) when three probiotic species such as Bacillus subtilis, Lactobacillus casein and Candida utilis were at a ratio of 1:1:1, corresponding with the predictive value of the RSM model. The further experiment showed that AFB₁ and ZEA degradation rates were 63.95% and 73.51% (P < 0.05) when the compound of three probiotic species was combined with mycotoxin-degradation enzymes from Aspergillus oryzae at a ratio of 3:2. This result indicated that the combination of probiotics with mycotoxin-degradation enzymes is a promising new approach for synchronous detoxification of AFB₁ and ZEA.

Influence of Bacillus subtilis ANSB060 on growth, digestive enzyme and aflatoxin residue in Yellow River carp fed diets contaminated with aflatoxin B1

Aflatoxin B₁ (AFB₁) elicits serious threats to public health due to its widespread occurrence, as well as its teratogenic, carcinogenic and mutagenic effects. This study aimed to evaluate the toxicity of AFB₁ and assess the ameliorative efficacy of Bacillus subtilis ANSB060 on aflatoxicosis in Yellow River carp. A total of 750 juvenile Yellow River carp were allocated into five dietary treatments for 60 days. Diet C0 represented for the negative control, diet M0 containing about 50 μg AFB₁/kg diet represented for the positive control, and diet M0.25, M0.5 and M1.0 was diet M0 supplemented with B. subtilis ANSB060 at a dose of 0.25 × 10⁹, 0.5 × 10⁹ and 1.0 × 10⁹ CFU/kg diet, respectively. The results showed that supplementation of strain ANSB060 restored the reduced body weight and enhanced feed conversion ratio of carp induced by AFB₁ towards normal. ANSB060 could also relieve the alterations in hepatic morphology, improve digestive enzyme activities of hepatopancreas and intestine, as well as decrease AFB₁ residues in carp's hepatopancreas and gonad. It is concluded that ANSB060 has a protective effect in carp with aflatoxicosis, with a promising potential in feed industrial applications.

Review on microbial degradation of aflatoxins

Aflatoxin (AF) contamination presents one of the most insidious challenges to combat, in food safety. Its adulteration of agricultural commodities presents an important safety concern as evident in the incidences of its health implication and economic losses reported widely. Due to the overarching challenges presented by the contamination of AFs in foods and feeds, there is an urgent need to evolve cost-effective and competent strategies to combat this menace. In our review, we tried to appraise the cost-effective methods for decontamination of AFs. We identified the missing links in adopting microbial degradation as a palliative to decontamination of AFs and its commercialization in food and feed industries. Cogent areas of further research were also highlighted in the review paper.

Strategies and Methodologies for Developing Microbial Detoxification Systems to Mitigate Mycotoxins

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.

Novel Aflatoxin-Degrading Enzyme from Bacillus shackletonii L7

Food and feed contamination by aflatoxin (AF)B₁ has adverse economic and health consequences. AFB₁ degradation by microorganisms or microbial enzymes provides a promising preventive measure. To this end, the present study tested 43 bacterial isolates collected from maize, rice, and soil samples for AFB₁-reducing activity. The higher activity was detected in isolate L7, which was identified as Bacillus shackletonii. L7 reduced AFB₁, AFB₂, and AFM₁ levels by 92.1%, 84.1%, and 90.4%, respectively, after 72 h at 37 °C. The L7 culture supernatant degraded more AFB₁ than viable cells and cell extracts; and the degradation activity was reduced from 77.9% to 15.3% in the presence of proteinase K and sodium dodecyl sulphate. A thermostable enzyme purified from the boiled supernatant was designated as Bacillus aflatoxin-degrading enzyme (BADE). An overall 9.55-fold purification of BADE with a recovery of 39.92% and an activity of 3.85 × 10³ U·mg-1 was obtained using chromatography on DEAE-Sepharose. BADE had an estimated molecular mass of 22 kDa and exhibited the highest activity at 70 °C and pH 8.0, which was enhanced by Cu2+ and inhibited by Zn2+, Mn2+, Mg2+, and Li⁺. BADE is the major protein involved in AFB₁ detoxification. This is the first report of a BADE isolated from B. shackletonii, which has potential applications in the detoxification of aflatoxins during food and feed processing.

Avaliação in vitro da adsorção de aflatoxina B1 por produtos comerciais utilizados na alimentação animal

RESUMO: Objetivou-se avaliar a capacidade de adsorção in vitro de aflatoxina B1 (AFB1) por produtos comerciais utilizados na alimentação animal. Muitas pesquisas estão sendo realizadas para a descontaminação de AFB1 em alimentos. Os produtos comerciais utilizados frequentemente na alimentação de peixes, disponíveis na forma de probióticos, são formados por cepas de bactérias e leveduras utilizadas na maioria dos ensaios de adsorção de micotoxinas. Foram utilizados três produtos comerciais: A, composto por Bacillus subtilis, Bifidobacterium bifidum, Enterococcus faecium e Lactobacillus acidophilus; B, por leveduras secas de Saccharomyces cerevisiae provenientes de cervejaria; e C, por Bacillus subtilis, Bacillus licheniformis e Bacillus pumilus. Cinco suspensões da dose máxima recomendada pelo fabricante de cada produto (0; 25; 50; 75 e 100%) foram testadas contra AFB1 (1000 ng.mL-1) em microtubos para determinação da capacidade de adsorção. Para simular o pH do estômago e do intestino de tilápias do Nilo (Oreochromis niloticus) foram formuladas soluções tampão fosfato salino (PBS), com pH 1,5 e 7,5; respectivamente. Os microtubos foram introduzidos em uma centrífuga com agitação mecânica, a 37ºC por 1 h e depois centrifugados por 10 min a 14.000 rpm; os sobrenadantes foram quantificados por cromatografia líquida de alta eficiência. Os produtos comerciais, nas concentrações máximas, foram capazes de adsorver AFB1 em quantidades de 45,01 a 129,59; 123,90 a 215,59 e 209,98 a 370,73 ng.mL-1, respectivamente. Concluiu-se que todos os produtos comerciais analisados adsorvem AFB1 em condições simuladas de pH gastrointestinal e são candidatos potenciais para adsorção de AFB1 para futuros ensaios in vivo.

Ameliorating Effects of Bacillus subtilis ANSB060 on Growth Performance, Antioxidant Functions, and Aflatoxin Residues in Ducks Fed Diets Contaminated with Aflatoxins

Bacillus subtilis ANSB060 isolated from fish gut is very effective in detoxifying aflatoxins in feed and feed ingredients. The purpose of this research was to investigate the effects of B. subtilis ANSB060 on growth performance, body antioxidant functions, and aflatoxin residues in ducks fed moldy maize naturally contaminated with aflatoxins. A total of 1500 18-d-old male Cherry Valley ducks with similar body weight were randomly assigned to five treatments with six replicates of 50 ducks per repeat. The experiment design consisted of five dietary treatments labeled as C0 (basal diet containing 60% normal maize), M0 (basal diet containing 60% moldy maize contaminated with aflatoxins substituted for normal maize), M500, M1000, and M2000 (M0 +500, 1000 or 2000 g/t aflatoxin biodegradation preparation mainly consisted of B. subtilis ANSB060). The results showed that ducks fed 22.44 ± 2.46 μg/kg of AFB₁ (M0) exhibited a decreasing tendency in average daily gain (ADG) and total superoxide dismutase (T-SOD) activity in serum, and T-SOD and glutathione peroxidase (GSH-Px) activities in the liver significantly decreased along with the appearance of AFB₁ and AFM₁ compared with those in Group C0. The supplementation of B. subtilis ANSB060 into aflatoxin-contaminated diets increased the ADG of ducks (p > 0.05), significantly improved antioxidant enzyme activities, and reduced aflatoxin accumulation in duck liver. In conclusion, Bacillus subtilis ANSB060 in diets showed an ameliorating effect to duck aflatoxicosis and may be a promising feed additive.

Review on biological degradation of mycotoxins

The worldwide contamination of feeds and foods with mycotoxins is a significant problem. Mycotoxins pose huge health threat to animals and humans. As well, mycotoxins bring enormous economic losses in food industry and animal husbandry annually. Thus, strategies to eliminate or inactivate mycotoxins in food and feed are urgently needed. Traditional physical and chemical methods have some limitations such as limited efficacy, safety issues, losses in the nutritional value and the palatability of feeds, as well as the expensive equipment required to implement these techniques. Biological degradation of mycotoxins has shown promise because it works under mild, environmentally friendly conditions. Aflatoxin (AF), zearalenone (ZEA) and deoxynivalenol (DON) are considered the most economically important mycotoxins in terms of their high prevalence and significant negative effects on animal performance. Therefore, this review will comprehensively describe the biological degradation of AF, ZEA and DON by microorganisms (including fungi and bacteria) and specific enzymes isolated from microbial systems that can convert mycotoxins with varied efficiency to non- or less toxic products. Finally, some strategies and advices on existing difficulties of biodegradation research are also briefly proposed in this paper.