Structural characterization of metabolites after the microbial degradation of type A trichothecenes by the bacterial strain BBSH 797

Abstract

Contamination of feed with trichothecenes, a group of Fusarium mycotoxins, leads to losses in performance due to their immunosupressive effects and the negative effect on the gastrointestinal system in animal production. A possible way of detoxification is microbial degradation, which was the focus of this study. A bacterial strain--BBSH 797--which can degrade some mycotoxins of the trichothecene group, has already been isolated. It transforms deoxynivalenol (DON) into its metabolite DOM-1, the non-toxic deepoxide of DON. Analogous to the microbial degradation of DON, the transformation of six different type A trichothecenes was observed. The metabolites appearing were characterized by GC-MS after derivatization with TRI-SIL TBT. Two metabolites were additionally, identified by liquid chromatography-mass spectrometry with particle beam interface (LC-PB-MS) with electron impact (EI)-ionization mode. The major finding was that scirpentriol was completely transformed into its non-toxic metabolite deepoxy scirpentriol, while the mycotoxin T-2 triol underwent a more complicated metabolism. According to the study, T-2-triol was degraded into its non-toxic deepoxy form and into T-2 tetraol, which was then further metabolized to deepoxy T-2 tetraol. GC-MS after derivatization with TRI-SIL TBT was suitable for the structural characterization of trichothecenes and their degradation products. Besides the mass spectra of already known degradation products, spectra of new metabolites could be recorded by LC-PB-MS.

Yeast cell based feed additives: studies on aflatoxin B1and zearalenone

“…(Fuchs et al 2002;Molnar et al 2004) or on the basis of adsorption of mycotoxins to binding agents in the animals' digestive system. Binders should be non-toxic, have a high adsorption capacity (so that their inclusion level into feed may be low) and bind mycotoxins selectively and irreversibly at different pH-values and in complex systems, like the digestive tract.…”

Reduced Contamination by the Fusarium Mycotoxin Zearalenone in Maize Kernels through Genetic Modification with a Detoxification Gene

“…Therefore, DON detoxification should also be considered together with the transgenic strategies of ZEN decontamination. Although genes for irreversible detoxification of trichothecenes are not currently available, numerous efforts are being made to solve the problems of DON contamination (6,14,15,19,23,24). In combination with such progress in biotechnological detoxification of DON, the transgenic system of detoxification of ZEN demonstrated in this paper will contribute significantly to solving the mycotoxin problems in maize and other cereals.…”

Novel strategies to control mycotoxins in feeds: A review

“…Ruminal or intestinal microflora are capable of detoxifying DON by enzymatic reduction of the epoxide ring, resulting in the metabolite DOM-1 that is known to be non-toxic. A pure anaerobic bacterial strain (Eubacterium BBSH 797), capable of the biotransformation of DON to DOM-1, was isolated from an enriched mixed culture obtained from bovine rumen content (Fuchs et al, 2002). This bacterium transformed DON and other trichothecenes within 24-48 h in in vitro experiments.…”