Recent advances on the use of adsorbent materials for detoxification of Fusarium mycotoxins

The extensive use of adsorbents in the livestock industry has led to the introduction of a wide range of new products on the market, most of them claiming high in vitro mycotoxin adsorption capacity. However, adsorbents that may appear effective in vitro do not necessarily retain their efficacy when tested in vivo. Studies performed in our laboratory during the past few years aiming to evaluate the efficacy of various adsorbent materials in binding Fusarium mycotoxins are reported. Adsorption experiments were performed in in vitro screening tests for Fusarium mycotoxins at different pHs; by in vivo tests using the increase of the sphinganine to sphingosine ratio in rat urine and tissues as a biomarker of fumonisin exposure; and by a dynamic, computer-controlled, gastrointestinal model simulating the gastrointestinal tract of healthy pigs. Most of the commercially available mycotoxin-binders failed in sequestering in vitro Fusarium mycotoxins. Only for a small number of adsorbent materials was the ability to bind more than one mycotoxin demonstrated. Cholestyramine was proven to be an effective binder for fumonisins and zearalenone in vitro, which was confirmed for zearalenone in experiments using a dynamic gastrointestinal model and for fumonisins in in vivo experiments. No adsorbent materials, with the exception of activated carbon, showed relevant ability in binding deoxynivalenol and nivalenol. The in vitro efficacy of activated carbon toward fumonisins was not confirmed in vivo by the biomarker assay. The dynamic gastrointestinal model was a reliable tool to study the effectiveness of adsorbent materials in reducing the bioaccessibility of Fusarium mycotoxins, as an alternative to the more difficult and time-consuming studies with domestic livestock.