Removal of common Fusarium toxins in vitro by strains of Lactobacillus and Propionibacterium

Abstract

This study was conducted to examine the ability of selected strains of Lactobacillus and Propionibacterium to remove common Fusarium toxins, trichothecenes, from liquid media. The trichothecenes studied were deoxynivalenol (DON), 3-acetyldeoxynivalenol (3-AcDON), nivalenol (NIV), fusarenon (FX), diacetoxyscirpenol (DAS), T-2 toxin (T-2) and HT-2 toxin (HT-2). The Lactobacillus rhamnosus strain GG (LGG), Lactobacillus rhamnosus strain LC-705 (LC-705) and Propionibacterium freudenreichii ssp. shermanii JS (PJS) were incubated in PBS buffer containing 20 microg toxin ml(-1) for 1h at 37 degrees C, and after centrifugation the concentration of the toxins was measured in the supernatant fraction. Both viable and heat-killed forms of LGG and PJS were more efficient than LC-705 in removing the toxins from the liquid media. LGG and PJS removed four of the seven tested toxins (the removal varying from 18 to 93%) and LC-705 two toxins (10-64%). Of the toxins, 3-AcDON was not removed by any of the bacteria; HT-2 was removed by the non-viable LGG and also slightly by non-viable LC-705; DAS was removed by all three bacteria tested. Binding is postulated as the possible mechanism of the removal, since no difference was observed between the ability of viable and heat-killed bacteria in removing the trichothecenes, and no degradation products of the toxins were detected by gas chromatography (GC)-mass spectrometry (MS) analysis. It is concluded that significant differences exist in the ability of the bacteria to bind trichothecenes in vitro.