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Aims:  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. Methods and Results:  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. Conclusions:  Selected fermentative bacteria are able to bind main Fusarium mycotoxins. Significance and Impact of the Study:  The binding ability of selected strains could be used to decrease the bioavailability of toxins in contaminated silages.

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Fermentative bacteria can potentially be utilized to detoxify corn silage contaminated by Fusarium toxins. The objective of the present study was to test a large number of these bacteria for their ability to bind and/or biotransform deoxynivalenol (DON), zearalenone (ZEN) and fumonisins B(1) and B(2) (FB(1), FB(2)) in conditions simulating corn silage. A total of 202 strains were screened in contaminated, pH 4, corn infusion inoculated with 5 x 10(8) CFU ml(-1). Eight Lactobacilli and three Leuconostoc biotransformed ZEN into alpha-zearalenol, but no biotransformation was detected for DON and fumonisins. In contrast, most strains were capable of binding Fusarium toxins. The most effective genera were Streptococcus and Enterococcus, capable of binding up to 33, 49, 24 and 62% of DON, ZEN, FB(1) and FB(2), respectively. The ability to bind Fusarium toxins seems to be a common property of fermentative bacteria and could help to decrease their toxicity in animals.

Aims:  The ability of lactic acid bacteria (LAB) to bind fumonisins B1 and B2 (FB1, FB2) in fermented foods and feeds and in the gastrointestinal tract could contribute to decrease their bioavailability and toxic effects on farm animals and humans. The aim of this work was to identify the bacterial cell wall component(s) and the functional group(s) of FB involved in the LAB–FB interaction. Methods and Results:  The effect of physicochemical, enzymatic and genetic treatments of bacteria and the removal/inactivation of the functional groups of FB on toxin binding were evaluated. Treatments affecting the bacterial wall polysaccharides, lipids and proteins increased binding, while those degrading peptidoglycan (PG) partially decreased it. In addition, purified PG from Gram‐positive bacteria bound FB in a manner analogue to that of intact LAB. For FB, tricarballylic acid (TCA) chains play a significant role in binding as hydrolysed FB had less affinity for LAB. Conclusions:  Peptidoglycan and TCA are important components of LAB and FB, respectively, involved in the binding interaction. Significance and Impact of the Study:  Lactic acid bacteria binding efficiency seems related to the peptide moiety structure of the PG. This information can be used to select probiotics with increased FB binding efficiency.