Preparation, purification and characteristics of an aflatoxin degradation enzyme from Myxococcus fulvus ANSM068

Effect of probiotic supplement on aflatoxicosis and gene expression in the liver of broiler chicken

The present study aimed to investigate the toxic effect of aflatoxin B1 (AFB1) and the effectiveness of a biological mycotoxin binder (Nutritox^®) in detoxifying aflatoxicosis. Ninety one-day-old chicks were chosen and divided into 3 groups. The first group received standard basal diet only, the second group received a basal diet with AFB1 (0.25 mg/kg diet), and the third group received a basal diet with AFB1 (0.25 mg/kg diet) and Nutritox^® (1 kg/ton diet). AFB1 feed contamination significantly reduced growth performance and deteriorated FCR. Moreover, it significantly increased serum AST, ALT, and malondialdehyde and significantly decreased serum total protein, albumin, globulin, SOD, CAT activities and glutathione peroxidase gene expression as well. Aflatoxin residues were detected in the liver tissues. Furthermore, the liver and kidney of AFB1 treated group showed pathological changes. The supplementation of Nutritox^® significantly reduced aflatoxin levels in the liver and counteracted the negative effects of AFB1.

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.

Pediococcus acidolactici and Pediococcus pentosaceus isolated from a rainbow trout ecosystem have probiotic and ABF1 adsorbing/degrading abilities in vitro

Probiotics are being used in biological control of bacterial pathogens, as an alternative to antibiotics, to improve health and production parameters in fish farming. Fish farming production is severely affected by aflatoxins (AFs), which are a significant problem in aquaculture systems. Aflatoxins exert substantial impact on production, causing disease with high mortality and a gradual decline of reared fish stock quality. Some aspects of aflatoxicosis in fish, particularly its effects on the gastrointestinal tract, have not been well documented. The aim of the present study was to evaluate probiotic properties of lactic acid bacterial (LAB) strains isolated from rainbow trout intestine and feed. Moreover, AFB₁-binding and/or degrading abilities were also evaluated to assess their use in the formulation of feed additives. Growth at pH 2, the ability to co-aggregate with bacterial pathogens, inhibition of bacterial pathogens, and determination of the inhibitory mechanism were tested. Aflatoxin B₁ (AFB₁) adsorption and degradation ability were also tested. All strains were able to maintain viable (10⁷ cells ml^-1) at pH 2. Pediococcus acidilactici RC001 and RC008 showed the strongest antimicrobial activity, inhibiting all the pathogens tested. The strains produced antimicrobial compounds of different nature, being affected by different treatments (catalase, NaOH and heating), which indicated that they could be H₂O_2, organic acids or proteins. All LAB strains tested showed the ability to coaggregate pathogenic bacteria, showing inhibition percentages above 40%. Pediococcus acidilactici RC003 was the one with the highest adsorption capacity and all LAB strains were able to degrade AFB₁ with percentages higher than 15%, showing significant differences with respect to the control. The ability of some of the LAB strains isolated in the present work to compete with pathogens, together with stability against bile and gastric pH, reduction of bioavailability and degradation of AFB₁, may indicate the potential of LAB for use in rainbow trout culture.

Mycotoxin Biotransformation by Native and Commercial Enzymes: Present and Future Perspectives

Worldwide mycotoxins contamination has a significant impact on animal and human health, and leads to economic losses accounted for billions of dollars annually. Since the application of pre- and post- harvest strategies, including chemical or physical removal, are not sufficiently effective, biological transformation is considered the most promising yet challenging approach to reduce mycotoxins accumulation. Although several microorganisms were reported to degrade mycotoxins, only a few enzymes have been identified, purified and characterized for this activity. This review focuses on the biotransformation of mycotoxins performed with purified enzymes isolated from bacteria, fungi and plants, whose activity was validated in in vitro and in vivo assays, including patented ones and commercial preparations. Furthermore, we will present some applications for detoxifying enzymes in food, feed, biogas and biofuel industries, describing their limitation and potentialities.

Aflatoxins: A Global Concern for Food Safety, Human Health and Their Management

The aflatoxin producing fungi, Aspergillus spp., are widely spread in nature and have severely contaminated food supplies of humans and animals, resulting in health hazards and even death. Therefore, there is great demand for aflatoxins research to develop suitable methods for their quantification, precise detection and control to ensure the safety of consumers' health. Here, the chemistry and biosynthesis process of the mycotoxins is discussed in brief along with their occurrence, and the health hazards to humans and livestock. This review focuses on resources, production, detection and control measures of aflatoxins to ensure food and feed safety. The review is informative for health-conscious consumers and research experts in the fields. Furthermore, providing knowledge on aflatoxins toxicity will help in ensure food safety and meet the future demands of the increasing population by decreasing the incidence of outbreaks due to aflatoxins.

Biotransformation and detoxification of aflatoxin B1 by extracellular extract of Cladosporium uredinicola

Aflatoxin contamination of food and grain poses a serious economic and health problem globally. Aflatoxin B1 (AFB1) is extremely mutagenic and toxic as well as a potent carcinogen to both humans and livestock. In this study, the degradation of AFB1 by extracellular extract of Cladosporium uredinicola was examined using high-performance liquid chromatography (HPLC), thin-layer chromatography (TLC), and liquid chromatography mass spectrometry. Within 24 h of incubation, AFB1 was efficiently eliminated by the culture supernatant of C. uredinicola (84.5±5.7%) at 37°C; the elimination was proven to be enzymatic, and the enzyme was thermostable. The biotransformation products of AFB1 detected by HPLC and TLC were proven to be the same compound. Analysis with LCMS showed that AFB1 was bio-transformed to a structurally different compound (m/z=365 [M+Na]+), which is first reported. The cytotoxicity study to HeLa cells indicated that culture supernatant-treated AFB1 is less toxic as compared with AFB1.

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.

Aflatoxin B₁ and M₁ Degradation by Lac2 from Pleurotus pulmonarius and Redox Mediators

Laccases (LCs) are multicopper oxidases that find application as versatile biocatalysts for the green bioremediation of environmental pollutants and xenobiotics. In this study we elucidate the degrading activity of Lac2 pure enzyme form Pleurotus pulmonarius towards aflatoxin B₁ (AFB₁) and M₁ (AFM₁). LC enzyme was purified using three chromatographic steps and identified as Lac2 through zymogram and LC-MS/MS. The degradation assays were performed in vitro at 25 °C for 72 h in buffer solution. AFB₁ degradation by Lac2 direct oxidation was 23%. Toxin degradation was also investigated in the presence of three redox mediators, (2,2′-azino-bis-[3-ethylbenzothiazoline-6-sulfonic acid]) (ABTS) and two naturally-occurring phenols, acetosyringone (AS) and syringaldehyde (SA). The direct effect of the enzyme and the mediated action of Lac2 with redox mediators univocally proved the correlation between Lac2 activity and aflatoxins degradation. The degradation of AFB₁ was enhanced by the addition of all mediators at 10 mM, with AS being the most effective (90% of degradation). AFM₁ was completely degraded by Lac2 with all mediators at 10 mM. The novelty of this study relies on the identification of a pure enzyme as capable of degrading AFB₁ and, for the first time, AFM₁, and on the evidence that the mechanism of an effective degradation occurs via the mediation of natural phenolic compounds. These results opened new perspective for Lac2 application in the food and feed supply chains as a biotransforming agent of AFB₁ and AFM₁.

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.

Aflatoxin B1 degradation by liquid cultures and lysates of three bacterial strains

Aflatoxin contamination remains a daunting issue to address in food safety. In spite of the efforts geared towards prevention and elimination of this toxin, it still persists in agricultural commodities. This has necessitated the search for other measures such as microbial degradation to combat this hazard. In this study, we investigated the biodegradation of aflatoxin B1 (AFB1), using lysates of three bacterial strains (Pseudomonas anguilliseptica VGF1, Pseudomonas fluorescens and Staphylococcus sp. VGF2) isolated from a gold mine aquifer. The bacterial cells were intermittently lysed in the presence and absence of protease inhibitors to obtain protease free lysates, subsequently incubated with AFB1 for 3, 6, 12, 24, and 48h to investigate whether any possible AFB1 degradation occurred using high performance liquid chromatography (HPLC) for detection. Results obtained revealed that after 6h of incubation, protease inhibited lysates of Staphylococcus sp. VGF2 demonstrated the highest degradation capacity of 100%, whereas P. anguilliseptica VGF1 and P. fluorescens lysates degraded AFB1 by 66.5 and 63%, respectively. After further incubation to 12h, no residual AFB1 was detected for all the lysates. Lower degrading ability was however observed for liquid cultures and uninhibited lysates. Data on cytotoxicity studies against human lymphocytes showed that the degraded products were less toxic than the parent AFB1. From this study, it can thus be deduced that the mechanism of degradation by these bacterial lysates is enzymatic. This study shows the efficacy of crude bacterial lysates for detoxifying AFB1 indicating potential for application in the food and feed industry.

A review of the efficacy of mycotoxin detoxifying agents used in feed in light of changing global environment and legislation

In the recent years, mycotoxins have undoubtedly gained a keen interest of the scientific community studying food safety. The main reason is their profound impact on both human and animal health. International surveys reveal a low percentage of feed samples being contaminated above permitted/guideline levels, developed to protect consumers of animal derived products. However, the deleterious impact of feed co-contaminated at low levels with numerous both known and regulated as well as novel mycotoxins on producing animals has been described. Associated effects on agro-economics world-wide include substantial pecuniary losses which are borne by the society as a whole. Even though good agronomic practice is thought to be the most effective way of preventing animal feed contamination, the EC have recognised the need to introduce an additional means of management of feed already contaminated with low-levels of mycotoxins to alleviate detrimental effects on agricultural production efficiency. This review discusses types of feed detoxifying agents described in scientific literature, their reported efficacy in both in vitro and in vivo systems, and comparison with available commercial formulations in the light of increasing knowledge regarding mycotoxin prevalence in the changing global environment.

The toxic effects of combined aflatoxins and zearalenone in naturally contaminated diets on laying performance, egg quality and mycotoxins residues in eggs of layers and the protective effect of Bacillus subtilis biodegradation product

The toxic effect of aflatoxins (AF) and zearalenone (ZEA) and their combination on laying performance, egg quality and toxins residues in eggs, as well as the efficacy of Bacillus subtilis biodegradation product (BDP) for ameliorating these effects in layers were evaluated. Layers were submitted to a two phase experiment. The first phase was an intoxication period (18-23 wk) with birds fed 7 (3 × 2 + 1) diets (3 treatments with mycotoxins: AF (123.0 μg/kg), ZEA (260.2 μg/kg), or AF + ZEA (123.0 + 260.2 μg/kg); 2 treatments with or without BDP (1000 g/t); and a control group contained no toxins nor BDP). The next phase was a recovery period (24-29 wk) in which birds were fed a toxin-free diet. In the intoxication period, AF and AF + ZEA groups exhibited lower egg production, feed intake and shell thickness, and higher AFB1, AFB2 and AFM1 residues as compared with the control group. In addition, AF and ZEA exerted synergistic effects on egg production and feed intake. Moreover, AF alone or combined with ZEA had a continuous toxic effect on laying performance in the recovery phase. Addition of BDP offset these negative effects, showing that BDP has a protective effect on layers fed contaminated diets.

AFM₁ in Milk: Physical, Biological, and Prophylactic Methods to Mitigate Contamination

Aflatoxins (AFs) are toxic, carcinogenic, immunosuppressive secondary metabolites produced by some Aspergillus species which colonize crops, including many dietary staple foods and feed components. AFB₁ is the prevalent and most toxic among AFs. In the liver, it is biotransformed into AFM₁, which is then excreted into the milk of lactating mammals, including dairy animals. AFM₁ has been shown to be cause of both acute and chronic toxicoses. The presence of AFM₁ in milk and dairy products represents a worldwide concern since even small amounts of this metabolite may be of importance as long-term exposure is concerned. Contamination of milk may be mitigated either directly, decreasing the AFM₁ content in contaminated milk, or indirectly, decreasing AFB₁ contamination in the feed of dairy animals. Current strategies for AFM₁ mitigation include good agricultural practices in pre-harvest and post-harvest management of feed crops (including storage) and physical or chemical decontamination of feed and milk. However, no single strategy offers a complete solution to the issue.

Protective Effects of Bacillus subtilis ANSB060 on Serum Biochemistry, Histopathological Changes and Antioxidant Enzyme Activities of Broilers Fed Moldy Peanut Meal Naturally Contaminated with Aflatoxins

The aim of this study was to investigate the toxic effects of aflatoxins and evaluate the effectiveness of Bacillus subtilis ANSB060 in detoxifying aflatoxicosis in broilers. A total of 360 one-week-old male broilers (Ross 308) were assigned to six dietary treatments for five weeks. The treatment diets were: C0 (basal diet); C1.0 (C0 + 1.0 g B. subtilis ANSB060/kg diet); M0 (basal diet formulated with moldy peanut meal); M0.5, M1.0 and M2.0 (M0 + 0.5, 1.0 and 2.0 g B. subtilis ANSB060/kg diet, respectively). The contents of aflatoxin B1, B2, G1 and G2 in the diets formulated with moldy peanut meal were 70.7 ± 1.3, 11.0 ± 1.5, 6.5 ± 0.8 and 2.0 ± 0.3 µg/kg, respectively. The results showed that aflatoxins increased (p < 0.05) serum aspartate transaminase activity, decreased (p < 0.05) serum glutathione peroxidase activity, and enhanced (p < 0.05) malondialdehyde contents in both the serum and liver. Aflatoxins also caused gross and histological changes in liver tissues, such as bile duct epithelium hyperplasia, vacuolar degeneration and lymphocyte infiltration. The supplementation of ANSB060 reduced aflatoxin levels in the duodenum and counteracted the negative effects of aflatoxins, leading to the conclusion that ANSB060 has a protective effect against aflatoxicosis and this protection is dose-related.

Aflatoxin B₁ degradation by a Pseudomonas strain

Aflatoxin B1 (AFB1), one of the most potent naturally occurring mutagens and carcinogens, causes significant threats to the food industry and animal production. In this study, 25 bacteria isolates were collected from grain kernels and soils displaying AFB1 reduction activity. Based on its degradation effectiveness, isolate N17-1 was selected for further characterization and identified as Pseudomonas aeruginosa. P. aeruginosa N17-1 could degrade AFB₁, AFB₂ and AFM₁ by 82.8%, 46.8% and 31.9% after incubation in Nutrient Broth (NB) medium at 37 °C for 72 h, respectively. The culture supernatant of isolate N17-1 degraded AFB₁ effectively, whereas the viable cells and intra cell extracts were far less effective. Factors influencing AFB1 degradation by the culture supernatant were investigated. Maximum degradation was observed at 55 °C. Ions Mn²⁺ and Cu²⁺ were activators for AFB1 degradation, however, ions Mg²⁺, Li⁺, Zn²⁺, Se²⁺, Fe³⁺ were strong inhibitors. Treatments with proteinase K and proteinase K plus SDS significantly reduced the degradation activity of the culture supernatant. No degradation products were observed based on preliminary LC-QTOF/MS analysis, indicating AFB₁ was metabolized to degradation products with chemical properties different from that of AFB₁. The results indicated that the degradation of AFB₁ by P. aeruginosa N17-1 was enzymatic and could have a great potential in industrial applications. This is the first report indicating that the isolate of P. aeruginosa possesses the ability to degrade aflatoxin.

Occurrence of mycotoxins in feed ingredients and complete feeds obtained from the Beijing region of China

Background

The current study was carried out to provide a reference for the control of mycotoxin contamination in feed ingredients and complete feeds for swine.

Methods

A total of 55 feed ingredients, including 14 corn, 13 wheat bran, 11 soybean meal and 17 dried distillers grains with solubles (DDGS) as well as 76 complete swine feeds including 7 creep feeds, 14 starter feeds, 14 grower feeds, 18 grower-finisher feeds, 10 gestating sow feeds, and 13 lactating sow feeds were randomly collected from 15 swine farms located in the Beijing region of China from July to August 2011. Immunoaffinity clean-up, using High-Performance Liquid Chromatography (HPLC) in combination with UV or Fluorescence Detection, was used for quantitative analysis of aflatoxin B₁ (AFB₁), deoxynivalenol (DON), zearalenone (ZEA) and ochratoxin A (OTA) in the ingredients and complete feeds.

Results

DON and ZEA were the most prevalent mycotoxins found. DON was detected at percentages of 93, 92, 54, 100 and 97% with a mean level of 1.01, 0.44, 0.05, 1.36 and 0.65 ppm in the samples of corn, wheat bran, soybean meal, DDGS and complete feeds, respectively. The detected percentages of ZEA were 100, 100, 54, 100 and 100 with mean levels of 109.1, 14.9, 9.2, 882.7 and 58.9 ppb in the same samples. In the wheat bran and soybean meal samples, the content of all four mycotoxins were below the maximum limits set by Chinese regulations while the percentage of samples that exceeded regulatory limits were 7, 57 and 7% for corn, and 7, 14 and 3% for the complete feeds for AFB₁, DON and OTA respectively. DDGS showed the most serious mycotoxin contamination and the percentage of samples that exceeded regulatory limits were 6, 88 and 41%, for AFB₁, DON and ZEA, respectively.

Conclusions

This paper is the first to present data on the natural occurrence of AFB₁, DON, ZEA and OTA in ingredients and complete feeds obtained from swine farms in China’s Beijing region. The data shows that feed ingredients and complete swine feeds obtained from these farms are most often contaminated with DON followed by contamination with AFB₁ and ZEA.

Aflatoxin detoxification by manganese peroxidase purified from Pleurotus ostreatus

Manganese peroxidase (MnP) was produced from white rot edible mushroom Pleurotus ostreatus on the culture filtrate. The enzyme was purified to homogeneity using (NH4)2SO4 precipitation, DEAE-Sepharose and Sephadex G-100 column chromatography. The final enzyme activity achieved 81 U mL(-1), specific activity 78 U mg(-1) with purification fold of 130 and recovery 1.2% of the crude enzyme. SDS-PAGE indicated that the pure enzyme have a molecular mass of approximately 42 kDa. The optimum pH was between 4-5 and the optimum temperature was 25 °C. The pure MnP activity was enhanced by Mn(2+), Cu(2+), Ca(2+) and K(+) and inhibited by Hg(+2) and Cd(+2). H2O2 at 5 mM enhanced MnP activity while at 10 mM inhibited it significantly. The MnP-cDNA encoding gene was sequenced and determined (GenBank accession no. AB698450.1). The MnP-cDNA was found to consist of 497 bp in an Open Reading Frame (ORF) encoding 165 amino acids. MnP from P. ostreatus could detoxify aflatoxin B1 (AFB1) depending on enzyme concentration and incubation period. The highest detoxification power (90%) was observed after 48 h incubation at 1.5 U mL(-1) enzyme activities.

Degradation of zearalenone in swine feed and feed ingredients by Bacillus subtilis ANSB01G

Zearalenone (ZEA) and its derivatives are mycotoxins that can cause oestrogenic effects and impair the reproductive physiology of animals, especially in female swine. Strategies to reduce or eliminate ZEA contamination in foods and feeds are very much needed. Among 36 bacterial isolates obtained from a variety of animal intestinal chyme, mouldy foods and feeds, soils, etc., five isolates demonstrated the ability to reduce more than 50% of ZEA in a liquid medium; ANSB01G isolate taken from normal broiler intestinal chyme reduced ZEA the most, by 88.65%. Using physiological, biochemical, and 16S rRNA gene sequence analysis methods, the ANSB01G isolate was identified as Bacillus subtilis. Under simulated intestinal tract conditions, the ANSB01G B. subtilis isolate degraded 84.58, 66.34 and 83.04% of ZEA in naturally contaminated maize, dried distillers’ grains with solubles, and swine complete feed, respectively. The highest degradation of ZEA occurred when the mycotoxin was co-incubated with the whole bacterial culture, resulting in a reduction of 88.65%, followed by 75.60% using culture supernatant, 26.11% using cell extracts, and 15.06% using viable cells. Treatments consisting of both heating and addition of proteinase K significantly reduced the rate of ZEA degradation in the culture supernatant, indicating that the ZEA degradation might be enzymatic. B. subtilis ANSB01G displayed resistance to simulated gastrointestinal tract environments and antimicrobial activities against several common bacterial pathogens, including Escherichia coli, Salmonella typhimurium and Staphylococcus aureus. These properties of B. subtilis ANSB01G suggest the possibility of its potential to effectively degrade ZEA in feed and to develop functional feed products for livestock industries.

Effects of Bacillus subtilis ANSB060 on growth performance, meat quality and aflatoxin residues in broilers fed moldy peanut meal naturally contaminated with aflatoxins

This study was conducted to investigate the toxic effects of aflatoxins and the efficacy of Bacillus subtilis ANSB060 for the amelioration of aflatoxicosis in broiler chickens. Six replicates of ten broilers each were assigned to one of seven dietary treatments, which were labeled C0 (basal diet); M0 (basal diet containing moldy peanut meal); C500 and C1000 (C0+500 or 1000 g/t aflatoxin biodegradation preparations, composed mainly of ANSB060); and M500, M1000 and M2000 (M0+500, 1000 or 2000 g/t aflatoxin biodegradation preparations). The concentrations of aflatoxin B₁, B₂, G₁ and G₂ in the moldy diets (M0, M500, M100 and M2000) fluctuated around 70.7±1.3, 11.0±1.5, 6.5±0.8 and 2.0±0.3 μg/kg, respectively. The results showed that the M0 diet caused a significant decrease in average daily weight gain and increased feed requirements, with a gain ratio increasing from d 8 to 42, deterioration in meat quality and aflatoxin residues in broilers' livers as compared with the C0 diet. The addition of ANSB060 to the aflatoxin-contaminated diets offset these negative effects, leading to the conclusion that ANSB060 has a protective effect on growth performance and meat quality while reducing the amount of aflatoxin residues in the livers of broilers fed naturally moldy peanut meal.

Microbial strategies to control aflatoxins in food and feed

Aflatoxins are a group of toxic and carcinogenic fungal metabolites. They are commonly found in cereals, nuts and animal feeds and create a significant threat to the food industry and animal production. Several strategies have been developed to avoid or reduce harmful effects of aflatoxins since the 1960s. However, prevention of aflatoxin contamination pre/post harvest or during storage has not been satisfactory and control strategies such as physical removing and chemical inactivating used in food commodities have their deficiencies, which limit their large scale application. It is expected that progress in the control of aflatoxin contamination will depend on the introduction of technologies for specific, efficient and environmentally sound detoxification. The utilisation of biological detoxification agents, such as microorganisms and/or their enzymatic products to detoxify aflatoxins in contaminated food and feed can be a choice of such technology. To date, many of the microbial strategies have only showed reduced concentration of aflatoxins and the structure and toxicity of the detoxified products are unclear. More attention should be paid to the detoxification reactions, the structure of biotransformed products and the enzymes responsible for the detoxification. In this article, microbial strategies for aflatoxin control such as microbial binding and microbial biotransformation are reviewed.