An integrated study on the interactions of Lactobacillus brevis components with deoxynivalenol and zearalenone

Abstract

Deoxynivalenol (DON) and zearalenone (ZEN) are toxic Fusarium mycotoxins that frequently contaminate food and feed, posing significant public health risks. Among mitigation strategies, biological methods using lactic acid bacteria (LAB; e.g., Lactobacillus spp.) show particular promise, as these microorganisms can effectively biodegrade mycotoxins into less toxic or inactive metabolites. This study explored the binding and biotransformation capabilities of Lactobacillus brevis components (S-layer, aryl-alcohol dehydrogenase, carboxylesterase, and lipoteichoic acid repeats) using computational docking and Fourier transform infrared (FTIR) spectroscopy. Docking simulations revealed stronger binding affinities for ZEN than DON, involving interactions with hydroxyl groups, oxygen atoms, alkyl chains, and aromatic rings. Enzymes formed stable complexes with mycotoxins, suggesting biotransformation potential. FTIR spectra after 24 hours of incubation revealed mycotoxin adsorption through interactions with bacterial cell wall components, indicated by C-H and C-C peak shifts. For DON, changes in OH and CO peaks suggested oxidation-reduction, likely mediated by aryl-alcohol dehydrogenase, producing 3-keto-DON and 3-epi-DON. For ZEN, shifts in OH, C-O, and CO peaks indicated lactone ring hydrolysis, likely catalyzed by carboxylesterase. These findings highlight L. brevis as a promising biocontrol agent that detoxifies DON and ZEN through binding and biotransformation, offering a potential strategy to mitigate mycotoxin contamination in food and feed.