Efficacy of hydrated sodium calcium aluminosilicate in reducing the toxicity of dietary zearalenone to mink

NovaSil clay for the protection of humans and animals from aflatoxins and other contaminants

Aflatoxin contamination of diets results in disease and death in humans and animals. The objective of the present paper was to review the development of innovative enterosorption strategies for the detoxification of aflatoxins. NovaSil clay (NS) has been shown to decrease exposures to aflatoxins and prevent aflatoxicosis in a variety of animals when included in their diets. Results have shown that NS clay binds aflatoxins with high affinity and high capacity in the gastrointestinal tract, resulting in a notable reduction in the bioavailability of these toxins without interfering with the utilization of vitamins and other micronutrients. This strategy is already being utilized as a potential remedy for acute aflatoxicosis in animals, and as a sustainable intervention via diet. Animal and human studies have confirmed the apparent safety of NS and refined NS clay (with uniform particle size). Studies in Ghanaians at high risk of aflatoxicosis have indicated that NS (at a dose level of 0.25% w/w) is effective at decreasing biomarkers of aflatoxin exposure and does not interfere with levels of serum vitamins A and E, or iron or zinc. A new spinoff of this strategy is the development and use of broad-acting sorbents for the mitigation of environmental chemicals and microbes during natural disasters and emergencies. In summary, enterosorption strategies/therapies based on NS clay are promising for the management of aflatoxins and as sustainable public health interventions. The NS clay remedy is novel, inexpensive, and easily disseminated.

Silage review: Mycotoxins in silage: Occurrence, effects, prevention, and mitigation

Ensiled forage, particularly corn silage, is an important component of dairy cow diets worldwide. Forages can be contaminated with several mycotoxins in the field pre-harvest, during storage, or after ensiling during feed-out. Exposure to dietary mycotoxins adversely affects the performance and health of livestock and can compromise human health. Several studies and surveys indicate that ruminants are often exposed to mycotoxins such as aflatoxins, trichothecenes, ochratoxin A, fumonisins, zearalenone, and many other fungal secondary metabolites, via the silage they ingest. Problems associated with mycotoxins in silage can be minimized by preventing fungal growth before and after ensiling. Proper silage management is essential to reduce mycotoxin contamination of dairy cow feeds, and certain mold-inhibiting chemical additives or microbial inoculants can also reduce the contamination levels. Several sequestering agents also can be added to diets to reduce mycotoxin levels, but their efficacy varies with the type and level of mycotoxin contamination. This article gives an overview of the types, prevalence, and levels of mycotoxin contamination in ensiled forages in different countries, and describes their adverse effects on health of ruminants, and effective prevention and mitigation strategies for dairy cow diets. Future research priorities discussed include research efforts to develop silage additives or rumen microbial innocula that degrade mycotoxins.

Risks for animal health related to the presence of zearalenone and its modified forms in feed

Zearalenone (ZEN), a mycotoxin primarily produced by Fusarium fungi, occurs predominantly in cereal grains. The European Commission asked EFSA for a scientific opinion on the risk to animal health related to ZEN and its modified forms in feed. Modified forms of ZEN occurring in feed include phase I metabolites α‐zearalenol (α‐ZEL), β‐zearalenol (β‐ZEL), α‐zearalanol (α‐ZAL), β‐zearalanol (β‐ZAL), zearalanone (ZAN) and phase II conjugates. ZEN has oestrogenic activity and the oestrogenic activity of the modified forms of ZEN differs considerably. For ZEN, the EFSA Panel on Contaminants in the Food Chain (CONTAM) established no observed adverse effect levels (NOAELs) for pig (piglets and gilts), poultry (chicken and fattening turkeys), sheep and fish (extrapolated from carp) and lowest observed effect level (LOAEL) for dogs. No reference points could be established for cattle, ducks, goats, horses, rabbits, mink and cats. For modified forms, no reference points could be established for any animal species and relative potency factors previously established from rodents by the CONTAM Panel in 2016 were used. The dietary exposure was estimated on 17,706 analytical results with high proportions of left‐censored data (ZEN about 60%, ZAN about 70%, others close to 100%). Samples for ZEN were collected between 2001 and 2015 in 25 different European countries, whereas samples for the modified forms were collected mostly between 2013 and 2015 from three Member States. Based on exposure estimates, the risk of adverse health effects of feed containing ZEN was considered extremely low for poultry and low for sheep, dog, pig and fish. The same conclusions also apply to the sum of ZEN and its modified forms.

Immuno-physiological alterations from AFB1 in rats counteracted by treatments with Lactobacillus paracasei BEJ01 and montmorillonite clay mixture

High contamination by aflatoxin B1 (AFB1) has been detected in Beja province (Tunisia) in many dairy products and animal feed, which has resulted in many tons of cereals and cereals being removed from the market, causing economic loss. While removal represents a means of reducing risk, exposures still occur. Studies have increasingly focused on means of AFB1 biodegradation/elimination using lactic acid bacteria and clay mineral. In the study here, Lactobacillus paracasei BEJ01 (LP) and montmorilonite clay (MT) were used to reduce the physio-/immunotoxicologic disorders that could develop in rats that underwent AFB1 exposures for a total of 7 consecutive days. The results indicated that rats treated with AFB1 (80 μg/kg BW) alone had significant decreases in lymphocytes in their blood (including B-lymphocytes, CD3(+), CD4(+), and CD8(+) T-lymphocyte subtypes, and NK cells), immunoglobulins (IgA and IgG) and pro-inflammatory cytokines; these rats also had altered oxidative stress status. In contrast, in rats treated with LP + MT (2 × 10(9) cfu/ml [∼ 2 mg/kg] + 0.5 mg MT/kg BW) for a total of 7 days before, concurrent with or after AFB1 treatment, there was a significant blockade/mitigation of each AFB1-impacted parameter. Moreover, treatment with the mixture at any point in relation to AFB1 treatment expectedly caused enhanced TNFα and IL-1β expression relative to control values; all other parameters were comparable to values noted in control rats. Alone, the mixture had no impact on host parameters. From the results here it may be concluded the the LP + MT mixture was effective in protecting these hosts against AFB1-induced immunologic/physiologic disorders and that LP + MT could prevent and/or mitigate AFB1 toxicities in vivo.

Interaction of Lactobacillus plantarum MON03 with Tunisian montmorillonite clay and ability of the composite to immobilize Zearalenone in vitro and counteract immunotoxicity in vivo

BACKGROUND AND AIM

The present study was conducted to determine the abilities of the living Lactobacillus plantarum MON03 (LP) cells, Tunisian montmorillonite clay and their composites to accumulate Zearalenone (ZEA) from a liquid medium and elucidate the preventive effect of their composite in ZEA-contaminated balb/c mice showing immunotoxicity disorders.

MATERIALS AND METHODS

In the in vitro study, LP (2 × 10(9) CFU/mL), TM (0.5 mg) and LP+TM were incubated with 50 µg mL(-1) ZEA for 0, 12 and 24 h. For the in vivo study, the composite MT+LP was evaluated also for possible protection regarding ZEA-immunotoxicity in Balb/c mice as a sensitive model.

RESULTS

Results indicated that TM and LP+TM had a high capacity of adsorbing ZEA 87.2 ± 2.1 and 94.2 ± 2.1%, respectively. However, LP alone able to remove only 78% after 24 h of incubation. The quantity of adsorbed ZEA by LP, TM and LP+TM were 39, 43,5 and 47 µg mL(-1) of PBS, respectively. The in vivo results indicated that mice orally exposed to ZEA- (40 mg/kg bw) for 2 weeks showed severe immunotoxicity typical of fusarotoxicosis regarding thymocytes and splenocytes cell viability count, IFN-γ, IL-12, TNF-α production and B-cell activation. Mice treated with LP and TM alone, and LP+MT in combination with ZEA were comparable to the control.

CONCLUSION

Both LP and TM are safe by themselves and their composite succeeded to exert a potential prevention by counteracting ZEA-immunotoxicity and can be implicated in the biotechnology of ZEA removal in human food and animal feed.

Preventive and therapeutic methods against the toxic effects of mycotoxins - a review

Ingredients used in animal feeds and their contamination with undesirable substances, such as mycotoxins, are fundamentally important both in terms of the quality of animal products and the potential human health impacts associated with the animal-based food production chain. Feed ingredients contaminated with mycotoxins may have a wide range of toxicological effects on animals. Therefore, mycotoxin contamination of feed ingredients constituting complete feed products represents an important potential hazard in farm animal production. This review summarises the potential effects of some preventive methods used during the storage of cereal grains as well as of nutritive (e.g. antioxidants, amino acids, fats) or non-nutritive compounds (e.g. pharmacological substances, carbon- or silica-based polymers) and detoxifying enzymes recommended for use against the toxic effects of different mycotoxins.

Reducing human exposure to aflatoxin through the use of clay: a review

Innovative sorption strategies for the detoxification of aflatoxins have been developed. NovaSil clay (NS) has been shown to prevent aflatoxicosis in a variety of animals when included in their diet. Results have shown that NS clay binds aflatoxins with high affinity and high capacity in the gastrointestinal tract, resulting in a notable reduction in the bioavailability of these toxins without interfering with the utilization of vitamins and other micronutrients. This strategy is being evaluated as a potential remedy for acute aflatoxicosis, and as a sustainable human intervention for aflatoxins via the diet. Phase I and II clinical trials confirmed the apparent safety of NS for further study in humans. A recent study in Ghanaians at high risk for aflatoxicosis has indicated that NS (at a dose level of 0.25%) is effective in decreasing biomarkers of aflatoxin exposure and does not interfere with the levels of serum vitamins A and E, and iron and zinc. In summary, enterosorption strategies/therapies based on NS clay are promising for the management of aflatoxins and as a sustainable public health intervention. The NS clay remedy is novel, inexpensive and easily disseminated. Based on the present research, aflatoxin sequestering clays should be rigorously evaluated in vitro and in vivo, and should meet the following criteria: (1) favourable thermodynamic characteristics of mycotoxin sorption, (2) tolerable levels of priority metals, dioxins/furans and other hazardous contaminants, (3) safety and efficacy in multiple animal species, (4) safety and efficacy in long-term studies, and (5) negligible interactions with vitamins, iron and zinc and other micronutrients.

Anti-genotoxic effect of hydrated sodium calcium aluminosilicate on genotoxicity to human lymphocytes induced by aflatoxin B1

The anti-genotoxic potential of hydrated sodium calcium aluminosilicate (HSCAS) was investigated using sister chromatid exchanges (SCEs) induced by aflatoxin B1 (AFB1) as genotoxic endpoint in human lymphocytes. Whole blood samples from two healthy male donors were used for this experiment and the effects of different concentrations of HSCAS (5 x 10(-6) and 1 x 10(-5) M) and AFB1 (1, 5 and 10 microM) were tested. The present results established that the frequencies of SCEs (at doses of 5 and 10 microM except for 1 microM) in lymphocytes were significantly increased by AFB1 compared to controls. When HSCAS was added alone at a molar ratio of 5 x 10(-6) and 1 x 10(-5), lymphocytes did not show significant increases in SCE frequencies, but SCE frequencies induced by the various concentrations of AFB1 could be significantly reduced by the presence of HSCAS (at both doses). In fact, HSCAS at 1 x 10(-5) M completely inhibited SCE formations caused by AFB1. These results suggest for the first time, that HSCAS can antagonize the ability of AFB1 to cause DNA damage that leads to the formation of SCEs.

Preventive role of aluminosilicate clay against induction of micronuclei and chromosome aberrations in bone-marrow cells of Balb/c mice treated with Zearalenone

Zearalenone (ZEN) is a potent estrogenic metabolite produced by some Fusarium species. No treatment has been successfully employed to remove ZEN contamination in foods. This study was conducted to evaluate the ability of hydrated sodium calcium aluminosilicate (HSCAS) to protect Balb/c mice against cytotoxicity and genotoxicity induced by ZEN. HSCAS was given via the oral route, either alone or simultaneously with a toxic intra-gastric dose of ZEN. The experimental approach comprised treatments of seven groups of mice. The first three groups received 400, 600 or 800 mg/kg bw of HSCAS. Two experimental groups received, respectively, ZEN alone (40 mg/kg bw, representing 8% of the LD(50)) and ZEN in combination with HSCAS at 400 mg/kg bw. The two control groups received distilled water and olive oil, respectively. The positive control groups received colchicine (4 mg/kg bw) for the micronucleus assay and mitomycin C (1mg/kg bw) for the chromosome aberration test. Forty-eight hours after treatment, the femur and tibia were dissected out and analyzed. The results show that ZEN was cytotoxic and genotoxic to Balb/c mice, as indicated by the increase in the frequencies of micronucleated polychromatic erythrocytes (PCEMN) and of chromosomal aberrations in bone-marrow cells. The simultaneous intra-gastric administration of HSCAS with ZEN resulted in a reduction in the number of PCEMN and a decrease of the chromosomal aberration frequency, and an increase in the number of polychromatic erythrocytes (PCE) in bone-marrow cells, compared with those in the group treated with ZEN alone. It could be concluded that HSCAS itself was safe and efficient in the prevention of the toxic effects of ZEN in the gastrointestinal tract.

In vitro assessment of adsorbents aiming to prevent deoxynivalenol and zearalenone mycotoxicoses

The high prevalence of the Fusarium mycotoxins, deoxynivalenol (DON) and zearalenone (ZON) in animal feeds in mild climatic zones of Europe and North America results in considerable economic losses, as these toxins affect health and productivity particularly of pigs from all age groups. The use of mycotoxin adsorbents as feed additives is one of the most prominent approaches to reduce the risk for mycotoxicoses in farm animals, and to minimise carry-over of mycotoxins from contaminated feeds into foods of animal origin. Successful aflatoxin adsorption by means of different substances (phyllosilicate minerals, zeolites, activated charcoal, synthetic resins or yeast cell-wall-derived products) has been demonstrated in vivo and in vitro. However, attempts to adsorb DON and ZON have been less encouraging. Here we describe the adsorption capacity of a variety of potential binders, including compounds that have not been evaluated before, such as humic acids. All compounds were tested at realistic inclusion levels for their capacity to bind ZON and DON, using an in vitro method that resembles the different pH conditions in the gastro-intestinal tract of pigs. Mycotoxin adsorption was assessed by chemical methods and distinct bioassays, using specific markers of toxicity as endpoints of toxicity in cytological assays. Whereas none of the tested substances was able to bind DON in an appreciable percentage, some of the selected smectite clays, humic substances and yeast-wall derived products efficiently adsorbed ZON (>70%). Binding efficiency was indirectly confirmed by the reduction of toxicity in the in vitro bioassays. In conclusion, the presented test protocol allows the rapid screening of potential mycotoxin binders. Like other in vitro assays, the presented protocol combining chemical and biological assays cannot completely simulate the conditions of the gastro-intestinal tract, and hence in vivo experiments remain mandatory to assess the efficacy of mycotoxin binders under practical conditions.

Preventive role of phyllosilicate clay on the Immunological and Biochemical toxicity of zearalenone in Balb/c mice

Zearalenone (ZEN), a mycotoxin produced by several Fusarium spp., is most commonly found as a contaminant in stored grain and has chronic estrogenic effects on mammals. ZEN and its metabolites have anabolic activities and induced severe stress on liver, kidney and immune system. The aims of the current study were twofold: (1) to investigate the changes in serum biochemical, immunological parameters and histological picture of spleen in ZEN-treated Balb/c mice and (2) to evaluate the safety and efficacy of HSCAS to ameliorate the deleterious effects of ZEN. The results indicated that a single dose of ZEN (40 mg/kg bw) significantly reduced total cholesterol, HDL, LDL, triglycerides, total protein, albumin, total count of WBCs, immunoglobulin profile (Ig A and Ig G) and T-cells subtypes (CD3+, CD4+, CD8+ and CD56+). Whereas, it significantly increased uric acid and urea and induced degenerative changes in the spleen tissues. Mice treated with HSCAS alone (400 mg/kg bw) were comparable to the control regarding all the tested parameters. While HSCAS at levels 600 and 800 mg/kg bw caused changes in some tested biochemical parameters. The combined treatment of ZEN and the lowest tested dose of HSCAS (400 mg/kg bw) showed a significant improvement of the immunological, biochemical and histological parameters. It could be concluded that HSCAS was effective in the protection against the hazards of ZEN at a dose as low as 400 mg/kg bw. These results supported our hypothesis that HSCAS tightly-bind and immobilized ZEN resulted in reduction of toxin bioavailability in animal's gastrointestinal tract.

The protective effect of hydrated sodium calcium aluminosilicate against haematological, biochemical and pathological changes induced by Zearalenone in mice

Hydrated sodium calcium aluminosilicate (HSCAS), an anticaking agent for mixed feed, was added alone or simultaneously with a toxic Zearalenone (ZEN) dose to balb/c mice and was evaluated for its ability to restore damages induced by ZEN. The latter is a mycotoxin produced by fusarium genera; it is mainly known to induce several toxic effects such as hepatotoxicity, immunotoxicity and nephrotoxicity on animals and humans. The experimental approach consisted of eight treatments of six mice each by 400 mg/kg bw or 5 g/kg bw of HSCAS. Two experimental groups have received respectively ZEN alone at 40 (8% of LD50) and at 500 mg/kg bw (LD50). Two other groups have received ZEN at 40 or 500 mg/kg bw combined respectively with HSCAS at 400 mg/kg bw and 5 g/kg bw. The control groups received water or olive oil. Forty-eight hours after treatment, blood samples were collected for haematological and serum biochemical parameters measurements. ZEN treatment significantly increased hematocrit, haemoglobin, white blood cells: lymphocytes, eosinophils, neutrophils, monocytes and the most of biochemical serum parameters; it significantly reduced platelets and induced degenerative changes in the hepatic and renal tissues; while, the mixture of HSCAS with ZEN induced a reestablishment of haematological parameters, levels of serum biochemical enzyme activities and histological pictures of both liver and kidney. It also prevented general toxicity of ZEN. This was observed by the shift of LD50 for this toxin. Thus, our data strongly suggested that deleterious effects of ZEN could be overcome or, at least, significantly were diminished by HSCAS. Moreover, this sorbent by itself did not show any toxic effects.

The role of natural and synthetic zeolites as feed additives on the prevention and/or the treatment of certain farm animal diseases: A review

The present review comments on the role of the use of zeolites as feed additives on the prevention and/or the treatment of certain farm animal diseases. Both natural and synthetic zeolites have been used in animal nutrition mainly to improve performance traits and, based on their fundamental physicochemical properties, they were also tested and found to be efficacious in the prevention of ammonia and heavy metal toxicities, poisonings as well as radioactive elements uptake and metabolic skeletal defects. During the last decade, their utilization as mycotoxin-binding adsorbents has been a topic of considerable interest and many published research data indicate their potential efficacy against different types of mycotoxins either as a primary material or after specific modifications related to their surface properties. Ingested zeolites are involved in many biochemical processes through ion exchange, adsorption and catalysis. Recent findings support their role in the prevention of certain metabolic diseases in dairy cows, as well as their shifting effect on nitrogen excretion from urine to faeces in monogastric animals, which results in lower aerial ammonia concentration in the confinement facilities. Moreover, new evidence provide insights into potential mechanisms involved in zeolites supporting effect on animals suffered from gastrointestinal disturbances, including intestinal parasite infections. All the proposed mechanisms of zeolites' effects are summarized in the present review and possible focus topics for further research in selected areas are suggested.

Prevention of zearalenone-induced hyperestrogenism in prepubertal mice

Previous methods for the control of zearalenone (ZEN)-induced hyperestrogenism in animals have proven largely ineffective. The main objective in this study was to identify an enterosorbent that decreases the dietary bioavailability, and subsequent estrogenic effects, of ZEN. Initial in vitro screenings in aqueous solution (4 microg ZEN/ml) indicated that an activated carbon (AC) was the most efficient sorbent (99%), followed by a combination of 2 parts AC plus 3 parts HEC (hectorite) (69%), cetylpyridinium-exchanged low-pH montmorillonite (CP-LPHM) clay (58%), hexadecyltrimethylammonium-exchanged low-pH montmorillonite (HDTMA-LPHM) clay (54%), and HEC alone (28%). Results from the adult hydra bioassay suggested that the addition of either AC or HEC effectively decreased the effects of ZEN on Hydra attenuata without toxicity, as was observed with the use of either CP-LPHM or HDTMA-LPHM. Based on these results, AC, HEC, and 2AC:3HEC were evaluated in prepubertal mice. At a dietary inclusion level of 0.8% (w/w), AC alone significantly protected mice against the estrogenic effects induced by 35 mg ZEN/kg feed. Inclusion of 1.2% HEC with the 0.8% AC showed no additional protection; whereas 1.2% HEC alone failed to decrease the estrogenic effects. Ground flaxseed (25% w/w) in the diet also elicited protection, but to a lesser extent. Preliminary studies suggested that three similar carbons failed to decrease ZEN bioavailability. These findings suggest that the AC used in this study may be efficacious as an enterosorbent in animals consuming ZEN-contaminated diets. However, further studies are needed to evaluate the binding specificity, as well as the safety of chronic exposure.

Assessing the zearalenone-binding activity of adsorbent materials during passage through a dynamic in vitro gastrointestinal model

A novel approach is presented herein to study the intestinal absorption of mycotoxins by using a laboratory model that mimics the metabolic processes of the gastrointestinal (GI) tract of healthy pigs. This model was used to evaluate the small-intestinal absorption of zearalenone from contaminated wheat (4.1 mg/kg) and the effectiveness of activated carbon and cholestyramine at four inclusion levels (0.25, 0.5, 1 and 2%) in reducing toxin absorption. Approximately 32% of ZEA intake (247 microg) was released from the food matrix during 6 h of digestion and was rapidly absorbed at intestinal level. A significant reduction of intestinal absorption of ZEA was found after inclusion of activated carbon or cholestyramine, even at the lowest dose of adsorbents, with a more pronounced effect exhibited by activated carbon. In particular, when 2% of activated carbon or cholestyramine was added to the meal the ZEA intestinal absorption was lowered from 32% of ZEA intake to 5 and 16%, respectively. The sequestering effect of both adsorbents took place already during the first 2 h of digestion and persisted during the rest of the experiment. The GI-model is a rapid and physiologically relevant method to test the efficacy of adsorbent materials in binding mycotoxins and can be used to pre-screen mycotoxin/adsorbent combinations as an alternative to animal experiments.

Characterization of clay-based enterosorbents for the prevention of aflatoxicosis

Appropriate chemical interventions that can block, retard, or significantly diminish foodborne exposure to aflatoxins are high priorities. A practical and effective approach to the aflatoxin problem has been the dietary inclusion of a processed calcium montmorillonite clay (HSCAS). HSCAS acts as an enterosorbent that rapidly and preferentially binds aflatoxins in the gastrointestinal tract resulting in decreased aflatoxin uptake and bioavailability. In mechanistic studies, we have shown that the intact dicarbonyl system in aflatoxin is essential for optimal sorption by HSCAS. Evidence also suggests that aflatoxins react at multiple sites on HSCAS clay surfaces (especially those within the interlayer region). Due to conceivable risks associated with the dietary inclusion of nonspecific binding agents, all aflatoxin enterosorbents should be tested in sensitive animal models for efficacy, safety, and the potential for nutrient interactions.

Mycotoxin detoxication of animal feed by different adsorbents

The contamination of animal feed with mycotoxins represents a worldwide problem for farmers. These toxins originate from molds whose growth on living and stored plants is almost unavoidable particularly under moist conditions. Mycotoxin-containing feed can cause serious diseases in farm animals resulting in suffering and even death and thus can cause substantial economic losses. The most applied method for protecting animals against mycotoxicosis is the utilization of adsorbents mixed with the feed which are supposed to bind the mycotoxins efficiently in the gastro-intestinal tract. Aluminosilicates are the preferred adsorbents, followed by activated charcoal and special polymers. The efficiency of mycotoxin binders, however, differs considerably depending mainly on the chemical structure of both the adsorbent and the toxin. This review describes the most important types of adsorbents and the respective mechanisms of adsorption. Data of the in vitro and in vivo efficacy of detoxication are given.

Zearalenone: incidence, toxigenic fungi and chemical decontamination in Egyptian cereals

An investigation was made for the occurrence of Zearalenone (ZEN) and Zearalenone producing fungi in cereals (corn, 50 samples; rice, 45 samples; wheat, 40 samples) collected from Egypt. ZEN was detected in 15 of 50 corn samples with an average concentration of 22.3 ppb. The incidence of ZEN in rice samples was 8.9% (4 samples of 45), and the average was 15.5 ppb. Out of 40 wheat samples 5 samples were contaminated with ZEN (12.5%) with an average of 8.8 ppb. Seventy-nine Fusarium strains belonging to 9 different species were isolated from Egyptian cereals, and when tested for ZEN production only 26 isolates were Zearalenone producer. Efficiency of H2O2 for destruction of ZEN in contaminated corn was studied at different concentration (3, 5 and 10%). The results revealed that per cent of disappearance of ZEN was found to be dependent upon the concentration of H2O2, temperature and period of exposure. The highest per cent of degradation was 83.9%, with 10% H2O2 at 80 degrees C for 16 h, followed by 75% at the same conditions for 8 h, while the lowest one obtained by 3% H2O2 at 50 degrees C for 2 h.

Oxidative degradation and detoxification of mycotoxins using a novel source of ozone

Practical methods to degrade mycotoxins using ozone gas (O3) have been limited due to low O3 production capabilities of conventional systems and their associated costs. Recent advances in electrochemistry (i.e. proton-exchange membrane and electrolysis technologies) have made available a novel and continuous source of O3 gas up to 20% by weight. It is possible that the rapid delivery of high concentrations of O3 will result in mycotoxin degradation in contaminated grains--with minimal destruction of nutrients. The major objectives of this study were to investigate the degradation and detoxification of common mycotoxins in the presence of high concentrations of O3. In this study, aqueous equimolar (32 microM) solutions of aflatoxins B1 (AfB1), B2 (AfB2), G1 (AfG1), G2 (AfG2), cyclopiazonic acid (CPA), fumonisin B1 (FB1), ochratoxin A (OA), patulin, secalonic acid D (SAD) and zearalenone (ZEN) were treated with 2, 10 and/or 20 weight% O3 over a period of 5.0 min and analysed by HPLC. Results indicated that AfB1 and AfG1 were rapidly degraded using 2% O3, while AfB2 and AfG2 were more resistant to oxidation and required higher levels of O3 (20%) for rapid degradation. In other studies, patulin, CPA, OA, SAD and ZEN were degraded at 15 sec, with no by-products detectable by HPLC. Additionally, the toxicity of these compounds (measured by a mycotoxin-sensitive bioassay) was significantly decreased following treatment with O3 for 15 sec. In another study, FB1 (following reaction with O3) was rapidly degraded at 15 sec, with the formation of new products. One of these appeared to be a 3-keto derivative of FB1. Importantly, degradation of FB1 did not correlate with detoxification, since FB1 solutions treated with O3 were still positive in two bioassay systems.

Effects of dietary exposure to fumonisins from Fusarium moniliforme culture material (M-1325) on the reproductive performance of female mink

Adult female mink (Mustela vison) were fed diets that contained Fusarium moniliforme culture material that provided low- or high-dose dietary concentrations of 86 or 200 ppm fumonisin B1, 22 or 42 ppm fumonisin B2, and 7 or 12 ppm fumonisin B3, respectively, from approximately two weeks prior to breeding through gestation and lactation. Breeding performance of the females was not affected by consumption of the fumonisin diets. However, 58% of the mated females fed the high-dose diet (254 ppm total fumonisins) whelped compared to 100% of those fed the control and low-dose diets (115 ppm fumonisins). There was a statistically significant, dose-dependent decrease in kit (young mink) body weights at birth and a notable, but non-significant, decrease in litter size. The percentage of stillborn kits was directly proportional to the concentration of fumonisins in the dams' diets. Fumonisin concentrations in milk collected from those fed the high-dose diets were approximately 0.7% of the dietary fumonisin concentrations. Lactational exposure to fumonisins did not significantly decrease kit survival from birth through three weeks of age. Hepatic cell vacuolation was present in 25% of the control and 80% of the high-dose adults. No treatment-related gross or histologic lesions were observed in the kit mink. Numerous differences in hematologic and serum chemical parameters were noted between the control and fumonisin-exposed mink.

Chronic toxicity of fumonisins from Fusarium moniliforme culture material (M-1325) to mink

Adult female mink (Mustela vison) were fed a diet that contained Fusarium moniliforme culture material that provided dietary concentrations of 89 ppm fumonisin B1, 21 ppm fumonisin B2, and 8 ppm fumonisin B3 for 87 days. During the trial, there was mild lethargy in the mink fed fumonisins, but no other clinical signs or differences in feed consumption (measured during the first two weeks), body weights, or survivability were observed between the fumonisin-treated and control mink. Several hematologic parameters (mean corpuscular hemoglobin concentration, plasma total solids, and lymphocyte concentration) and serum chemical concentrations (globulin, phosphorus, potassium, blood urea nitrogen, creatinine, bilirubin, and cholesterol) and activities (alkaline phosphatase, alanine aminotransferase, amylase, and aspartate aminotransferase) were greater in the mink fed fumonisins than in the controls. Serum albumin/globulin and sodium/potassium ratios and chloride concentrations were lower in the fumonisin-fed mink than in the controls. The concentrations of free sphinganine and the ratio of free sphinganine to free sphingosine in the liver and kidneys of the fumonisin-treated mink were greater than in the control mink. No histopathologic alterations were associated with fumonisin treatment. These results indicate that long-term dietary exposure to F. moniliforme culture material containing 118 ppm total fumonisins is not lethal to adult mink, but can produce adverse physiological effects in the animals.

Effects of zearalenone and/or tamoxifen on swine and mink reproduction

Tamoxifen (TAM), which binds to estrogen receptors and can act as an estrogen antagonist, was incorporated into the diets of swine and mink to determine if it would ameliorate the effects of the estrogenic mycotoxin zearalenone (ZEN). Sows and female mink were fed diets containing 2 ppm (swine) or 20 ppm (mink) ZEN and/or 10 ppm TAM from day 30 of gestation through weaning (swine) or from 2 months prior to breeding through weaning (mink). The diets containing ZEN and/or TAM did not adversely affect reproduction in the sows. Although some hyperestrogenic effects on testes, uterine and ovarian weights were observed in the F1 piglets at 21 days of age, subsequent breeding performance was not affected. All the female mink exposed to ZEN mated, but only 25% whelped. No mink fed TAM (singly or in combination with ZEN) mated. Necropsy of these unmated females fed TAM revealed consistent severe pyometra. Histological examination of the reproductive tracts of the ZEN, TAM and ZEN + TAM-treated mink showed similar alterations, including ovarian follicular atrophy and degeneration, and mild to severe uterine atrophy, pyometra and endometritis. The results of these studies indicate that TAM was not effective in ameliorating the hyperestrogenic effects of ZEN in swine and mink, but rather it acted as an estrogen agonist.