The use of a dynamic in vitro model of the gastrointestinal tract (TIM) in studying mycotoxin adsorbents

Mycotoxins such as aflatoxins, ochratoxins, trichothecens, zearalenone and fumonisins are presently considered economically and toxicologically important. Since these mycotoxins produce diseases in animals and humans, strategies have been undertaken to decontaminate mycotoxin-containing foodstuffs. One of the most recent approaches involves inert binders from different sources, such as hydrated sodium calcium aluminiosilicate (HSCAS), zeolites, smectites, sepiolite and activated carbons. When added to the feed they reduce mycotoxin toxicity in animals and carryover of mycotoxin from contaminated foodstuffs to animal products. Binders act by reducing the bioavailability of mycotoxins through adsorption on their surface. The efficacy of a binder is determined by critical parameters as affinity of the binder to the mycotoxin and the stability of the binder-mycotoxin complex, especially during gastrointestinal transit. The efficacy of mycotoxin adsorbents to reduce the bioavailability of mycotoxins in the gut, as well as their possible effect on the absorption of nutrients, is preferably studied in in vitro systems with a high predictive value for the in vivo performance. The reason is simple: it is not possible to perform studies in animals with all varieties of binders in different types of feed matrices. However, the question is: what is the relevance of the results from these in vitro systems in comparison to the situation in animals? This paper describes a dynamic, computer-controlled system which mimics the successive kinetic events in the gastrointestinal tract (GI tract) and has been validated in comparison to in vivo studies. Furthermore, we will demonstrate how TIM is applied in testing the efficacy of mycotoxin binders.