Binding of Fusarium mycotoxins by fermentative bacteria in vitro

Fusarium toxins can occur in conserved forages impairing farm animal performances and health. On-farm biological decontamination methods could be an alternative to traditional physico-chemical methods. In this work, the ability to remove Fusarium toxins by fermentative bacteria was evaluated in vitro. Twenty-nine strains of lactic (LAB) and propionic acid bacteria (PAB) were tested for their ability to remove deoxynivalenol (DON) and fumonisins B₁ and B₂ (FB₁, FB₂) from an acid, pH 4, medium. Mycotoxin removal was widespread for LAB, but differences among strains were large. Removal was up to 55% for DON, 82% for FB₁ and 100% for FB₂. Selected strains were also capable of removing up to 88% zearalenone. The PAB strains were less efficient than the LAB. Binding, not biodegradation appeared to be the mode of action, as no toxin derivatives were observed and removal was not impaired in nonviable bacteria. Binding was not affected by pH, except for fumonisins that decreased to nearly 0% at neutral pH. Selected fermentative bacteria are able to bind main Fusarium mycotoxins. The binding ability of selected strains could be used to decrease the bioavailability of toxins in contaminated silages.