Grape pomace (pulp and skins) was investigated as a new biosorbent for removing mycotoxins from liquid media. In vitro adsorption experiments showed that the pomace obtained from Primitivo grapes is able to sequester rapidly and simultaneously different mycotoxins. Aflatoxin B-1 (AFB(1)) was the most adsorbed mycotoxin followed by zearalenone (ZEA), ochratoxin A (OTA), and fumonisin B-1 (FB1), whereas the adsorption of deoxynivalenol (DON) was negligible. AFB(1) and ZEA adsorptions were not affected by changing pH values in the pH 3-8 range, whereas OTA and FB1 adsorptions were significantly affected by pH. Equilibrium adsorption isotherms obtained at different temperatures (5-70 degrees C) and pH values (3 and 7) were modeled and evaluated using the Freundlich, Langmuir, Sips, and Hill models. The goodness of the fits and the parameters involved in the adsorption mechanism were calculated by the nonlinear regression analysis method. The best-fitting models to describe AFB(1), ZEA, and OTA adsorption by grape pomace were the Sips, Langmuir, and Freundlich models, respectively. The Langmuir and Sips models were the best models for FB1 adsorption at pH 7 and 3, respectively. The theoretical maximum adsorption capacities (mmol/kg dried pomace) calculated at pH 7 and 3 decreased in the following order: AFB(1) (15.0 and 15.1) > ZEA (8.6 and 8.3) > OTA (6.3-6.9) > FB1 (2.2 and 0.4). Single- and multi-mycotoxin adsorption isotherms showed that toxin adsorption is not affected by the simultaneous presence of different mycotoxins in the liquid medium. The profiles of adsorption isotherms obtained at different temperatures and pH and the thermodynamic parameters (Delta G degrees, Delta H degrees, Delta S degrees) suggest that mycotoxin adsorption is an exothermic and spontaneous process, which involves physisorption weak associations. Hydrophobic interactions may be associated with AFB(1) and ZEA adsorption, whereas polar noncovalent interactions may be associated with OTA and FB1 adsorption. In conclusion, this study suggests that biosorption of mycotoxins onto grape pomace may be a reasonably low-cost decontamination method.

Mycotoxins have become one of the most recognised feed chain contaminants, with hundreds of mycotoxins identified to date. Management of mycotoxins includes prevention, regulation, monitoring, decontamination, detoxification and animal treatments. Even with good management, unavoidably low levels of several mycotoxins can cause loss of feedstuffs, increased animal disease, reduced animal performance, and food residues. A promising approach to protect animals against the harmful effects of mycotoxin contaminated feed is based on the use of feed additives. These additives are defined as substances that, when included into contaminated feed, can adsorb or denature mycotoxins in the digestive tract of animals. Since 2009, the use of these substances is officially allowed in the European Union as technological feed additives. Depending on the mode of action, these additives may act either by degrading or transforming mycotoxins into less toxic metabolites (biotransformation) or by binding mycotoxins to their surface (adsorption). Mycotoxin adsorbents are the most studied feed additives and are successfully used worldwide to reduce the absorption of mycotoxins from the gastrointestinal tract and their distribution to blood and target organs. A number of products including indigestible adsorbent materials such as silicates, activated carbons, complex carbohydrates and others have been shown to be effective. Decreasing the bioavailability of aflatoxins by the inclusion of binding agents is particularly effective, as this group of toxins has a chemical structure which favours adsorption, especially by materials of mineral origin such as clay and zeolites. Ochratoxin A, zearalenone and fumonisin adsorption by biological adsorbents has been extensively studied due to the inefficiency of mineral adsorbents. Deoxynivalenol and T-2 or HT-2 toxins do not bind easily to a type of binding agents. So far, a mycotoxin adsorbent product that meets all the desirable characteristics is not available; most of them cannot adsorb a wide range of mycotoxins and may have adverse nutritional effects. Organic adsorbing agents such as yeasts have a well-known ability to stimulate the immune system, providing a good resistance to infectious diseases. An overview of the most important types of mycotoxin adsorbents will be presented together with the relevant effectiveness, problems, current trends and future perspectives.

The efficacy of four agricultural byproducts (ABPs) and two commercial binders (CBs) to reduce the gastrointestinal absorption of a mixture of mycotoxins was tested in piglets using urinary mycotoxin biomarkers as indicator of the absorbed mycotoxins. Twenty-eight piglets were administered a bolus contaminated with the mycotoxin mixture containing or not ABP or CB. Twenty-four hour urine was collected and analyzed for mycotoxin biomarkers by using a multiantibody immunoaffinity-based LC-MS/MS method. Each bolus contained 769 ?g of fumonisin B1 (FB1), 275 ?g of deoxynivalenol (DON), 29 ?g of zearalenone (ZEN), 6.5 ?g of aflatoxin B1 (AFB1) and 6.6 ?g of ochratoxin A (OTA) corresponding to 2.2,0.8, 0.08, 0.02, and 0.02 ?g/g in the daily diet, respectively. The percentage of ABP in each bolus was 50%, whereas for the two CBs the percentages were 5.2 and 17%, corresponding to 2.8, 0.3, and 0.9% in the daily diet, respectively. The reduction of mycotoxin absorption was up to 69 and 54% for ABPs and CBs, respectively. White grape pomace of Malvasia was the most effective material as it reduced significantly (p < 0.05) urinary mycotoxin biomarker of AFB1 (67%) and ZEN (69%), whereas reductions statistically not significant were observed for FB1 (57%), DON (40%), and OTA (27%). This study demonstrates that grape pomace reduces the gastrointestinal absorption of mycotoxins. This agricultural byproduct can be considered an alternative to commercial products and used in the feed industries as an effective, cheap, and natural binder for multiple mycotoxins.

Mycotoxins have become one of the most recognised feed chain contaminants, with hundreds of mycotoxins identified to date. Management of mycotoxins includes prevention, regulation, monitoring, decontamination, and animal treatments. Even with good management, unavoidably low levels of several mycotoxins can cause loss of feedstuffs, increased animal disease, reduced animal performance, and food residues. A promising approach to protect animals against the harmful effects of contaminated feed is based on the use of feed additives. These additives are defined as substances that, when included into contaminated feed, can adsorb or denature mycotoxins in the digestive tract of animals. Since 2009, they are officially allowed in the UE as technological feed additives. Mycotoxin adsorbents are the most studied additives and a variety of products are on the market claiming multi-toxin adsorption capacity. The efficacy of adsorbents in sequestering different mycotoxins has been poorly addressed. The aim of this study was the screening of commercial products for preparing a nutritional composition intended to reduce bioavailability of a large range of mycotoxins. 52 commercial products from 26 industrial partners, including minerals, yeast-based products and blend of components, were tested. Preliminary adsorption tests allowed the selection of 4 commercial products as effective in sequestering simultaneously aflatoxin B1, zearalenone, ochratoxin A and fumonisin B1. All products failed in adsorbing deoxynivalenol, but activated carbon. Adsorption experiments were performed with selected binders, at physiologically relevant pH values commonly found in the stomach and intestine, to determine adsorption parameters (capacity, affinity, chemisorption index). Mineralogical analysis (XRD) and ash content showed that 3 out of the 4 commercial products selected as best multi-toxin adsorbents (designated by the supplying companies as minerals) were organoclays. Organoclays are not suitable for feed ingredients due to toxicity of the interlayer quaternary alkylammonium ions. Two organoclays and one yeast cell wall product, out of 52 commercial products, were found toxic in 2 bioassays. In conclusion, multi-toxin adsorbents covering major mycotoxins are not commercially available. Most of them lack effectiveness towards trichotechenes. The identity/composition of commercial products could be counterfeit and misleading. Some commercial products can be even highly toxic in toxicity bioassays.

Mycotoxin contamination and co-occurrence of aflatoxin B1 (AFB1), deoxynivalenol (DON), zearalenone (ZEA), ochratoxin A (OTA) and fumonisin B1 (FB1) in animal feed are frequently observed and can impact animal health also at low doses. The addition of binders to contaminated diets is considered a promising dietary approach to reduce toxic effects of mycotoxins. In the EU, the use of these substances as technological feed additives has been officially approved and a variety of products are on the market claiming multi-toxin binding capacities. The efficacy of binders in sequestering different mycotoxins has been poorly addressed. The aim of this study was the screening of commercial products for preparing a nutritional composition intended to reduce bioavailability of a large range of mycotoxins. 52 commercial products from 26 industrial partners, including minerals, yeast-based products and blend of components, were tested. Preliminary adsorption tests allowed the selection of 4 commercial products as effective in sequestering simultaneously AFB1, ZEA, OTA and FB1. All products failed in binding DON, but activated carbon. Adsorption experiments were performed at physiologically relevant pH values commonly found in the stomach and intestine (pH 3.0 and 7.0) with selected binders to determine adsorption parameters (capacity, affinity, chemisorption index). Mineralogical analysis (XRD) and ash content showed that 3 out of the 4 commercial products selected as best multi-toxin adsorbents (designated by the supplying companies as minerals) were organoclays. Organoclays are not suitable for feed ingredients due to toxicity of the interlayer quaternary alkylammonium ions. Two organoclays and one yeast cell wall product, out of 52 commercial products, were found toxic in 2 bioassays. In conclusion, multi-toxin adsorbents covering major mycotoxins are not commercially available. Most of them lack effectiveness towards trichotechenes. The identity/composition of commercial products could be counterfeit and misleading. Some commercial products can be even highly toxic in toxicity bioassays.

Mycotoxin contamination and co-occurrence of aflatoxin B1 (AFB1), deoxynivalenol (DON), zearalenone (ZEA), ochratoxin A (OTA) and fumonisin B1 (FB1) in animal feed are frequently observed and can impact animal health also at low doses. The addition of binders to contaminated diets is considered a most promising dietary approach to reduce toxic effects of mycotoxins. In the EU, the use of these substances as technological feed additives has been officially approved and a variety of products are on the market claiming multi-toxin binding capacities. The efficacy of binders in sequestering different mycotoxins has been poorly addressed. The aim of this study was the screening of commercial products and agricultural by-products for preparing a nutritional composition intended to reduce bioavailability of a large range of mycotoxins. 52 commercial products from 26 industrial partners, including minerals, yeast-based products and blend of components, and 37 agricultural by-products were tested. Preliminary adsorption tests allowed to select 4 commercial products and 4 agricultural by-products as effective in sequestering simultaneously AFB1, ZEA, OTA and FB1. All products failed in binding DON, but activated carbon. Batch adsorption experiments were performed at different pHs with selected binders to determine adsorption parameters (capacity, affinity, chemisorption index), and kinetic and thermodynamic parameters. Mineralogical analysis (XRD) showed that 3 out of the 4 commercial products selected as best multi-toxin adsorbents (designated by the supplying companies as minerals) were organoclays. All these products showed lower maximum adsorption capacity and chemisorption index than a mineral product containing carbon. The latter was found to be the most effective, adsorbing simultaneously up to 34 mg AFB1, 184 mg ZEA, 256 mg OTA and 332 mg FB1 per gram of product. Most commercial additives, but two organoclays and one yeast cell wall product, were found to be non-toxic in 2 bioassays. Interestingly, some micronized vegetable dried materials were successful in adsorbing mycotoxins. Contact time curves showed that the simultaneous adsorption of AFB1, ZEA, OTA and FB1 by these materials is rapid, reaching the adsorption equilibrium within 10 min. Toxin adsorption was improved when the sizes of agricultural materials in the form of micro-particles were less than 500 µm. Medium pH did not affect toxin adsorption. Based on Langmuir equilibrium isotherms, selected products sequestered simultaneously up to 3.0 mg AFB1, 3.2 mg ZEA, 2.4 mg OTA and 0.1 mg FB1 per gram of product. Single and multi-component adsorption isotherms showed that AFB1, ZEA and FB1 adsorptions is not influenced by the simultaneous presence of different toxins. Thermodynamic parameters suggested that hydrophobic interaction could be associated to AFB1 and ZEA adsorption, while electrostatic interaction could be responsible for OTA and FB1 binding. In conclusion, this study shows that mo

Ochratoxin A contamination of red wines might be quite severe in certain high-risk regions and vintages, thus requiring corrective measures to fulfill acceptable standards for human consumption. This work proposes an innovative and environmentally friendly corrective measure to reduce ochratoxin A levels by repassage of contaminated musts or wines over grape pomaces having no or little ochratoxin A contamination. Grape pomaces have a high affinity for ochratoxin A and have been shown to remove ochratoxin A from must and wine during vinification. Time course experiments showed that ochratoxin A adsorption by pomaces is a rapid process, reaching equilibrium in less than 10 h, and is not affected by the tested toxin concentrations. Repassage of wine from Primitivo grapes spiked with 2-10 mu g/kg ochratoxin A over pomaces obtained from the same grapes removed up to 65% ochratoxin A within 24 h. Similar results (50-65% ochratoxin A reduction) were obtained with Primitivo or Negroamaro wines repassed over pomaces from different grape varieties including white grapes (Malvasia, Greco di Tufo) and red grapes (Sangiovese, Aglianico). Grape pomaces maintained a good efficacy in removing ochratoxin A after being reused four times. Unlike other enological fining agents, the use of grape pomaces to adsorb ochratoxin A from red wines of the same grape variety (Primitivo) did not affect relevant wine quality parameters, including color intensity and health-promoting phenolic content (trans-resveratrol, quercetin, total polyphenols). These quality parameters were instead positively or negatively affected when contaminated wines were repassed over grape pomaces from other grape varieties, the effect being related to the intrinsic characteristics of the pomace variety. The proposed decontamination procedure can be applied in a modern winery provided that contaminated grapes are identified early and processed separately from uncontaminated grapes.

A model of the stomach and small intestine (TIM-1) has been developed and validated as a reproducible system to simulate the gastrointestinal tract of monogastric animals (pigs, pre-ruminant calves and dogs) and humans (babies and adults). Simulating predetermined physiological parameters, such as meal size, peristaltic movements, pH, gastric and intestinal secretions, gastrointestinal transit, and absorption of digested products and water, the model is suitable for studies on digestion and bioaccessibility of food compounds and is a good alternative to in vivo experiments. The TIM-1 system, set-up to simulate the in vivo conditions of the porcine gastrointestinal tract, was used to determine the bioaccessibility of the ingested mycotoxins from two multi-toxin contaminated diets and the efficacy of a carbon/aluminosilicate-based product in reducing mycotoxin bioaccessibility. Mycotoxin levels in the diets were 19.9 and 5.9 mg/kg of fumonisins B1 and B2 (FB1 and FB2), 5.6 mg/kg of deoxynivalenol (DON), 1.3 mg/kg of zearalenone (ZEA), 0.187 mg/kg of ochratoxin A (OTA), and 0.193 mg/kg of aflatoxin B1 (AFB1). Mycotoxins were absorbed from the small intestine at levels of 105% and 89% for FB1 and FB2, respectively, 87% for OTA, 74% for DON, 44% for AFB1, and 25% for ZEA. The absorption of mycotoxins occurred mainly from the middle part of the small intestine (jejunum) and less from the ileum. Samples collected at different time intervals showed that, with the exception of ZEA, maximum absorption of mycotoxins occurred in the first 2 h of digestion (0-2 h), was persistent for the following 2 h (2-4 h), and decreased during the later 2 h (4-6 h) of the experiment. ZEA was less and slowly absorbed in comparison to the other mycotoxins. These mycotoxin bioaccessibility data are similar to published in vivo data, showing the predictive quality of TIM-1. Supplementation of the diets with the commercial product significantly reduced the mycotoxin absorption in a dose-dependent manner, up to 88% for AFB1, 44% for ZEA, and 29% for the fumonisins and OTA. The product was ineffective in reducing DON uptake. The findings of this study can help to interpret the in vivo studies on toxicology and carcinogenicity of mycotoxins and show that the TIM-1 system is a rapid and physiologically relevant method to test the efficacy of mycotoxin binders.