Binding Rather Than Metabolism May Explain the Interaction of Two Food-Grade Lactobacillus Strains with Zearalenone and Its Derivative ά-Zearalenol

• Published in: Applied and environmental microbiology 2002-07, Vol.68 (7), p.3545-3549
• Main Authors: El-Nezami, Hani, Polychronaki, Nektaria, Salminen, Seppo, Mykkänen, Hannu
• Format: Article
• Language: English
• Subjects: Food Microbiology
• ISSN: 0099-2240; 1098-5336
• DOI: 10.1128/AEM.68.7.3545-3549.2002

The interaction between two Fusarium mycotoxins, zearalenone (ZEN) and its derivative ¯α-zearalenol (¯α-ZOL), with two food-grade strains of Lactobacillus was investigated. The mycotoxins (2 μg ml −1 ) were incubated with either Lactobacillus rhamnosus strain GG or L. rhamnosus strain LC705. A considerable proportion (38 to 46%) of both toxins was recovered from the bacterial pellet, and no degradation products of ZEN and ¯α-ZOL were detected in the high-performance liquid chromatograms of the supernatant of the culturing media and the methanol extract of the pellet. Both heat-treated and acid-treated bacteria were capable of removing the toxins, indicating that binding, not metabolism, is the mechanism by which the toxins are removed from the media. Binding of ZEN or ¯α-ZOL by lyophilized L. rhamnosus GG and L. rhamnosus LC705 was a rapid reaction: approximately 55% of the toxins were bound instantly after mixing with the bacteria. Binding was dependent on the bacterial concentration, and coincubation of ZEN with ¯α-ZOL significantly affected the percentage of the toxin bound, indicating that these toxins may share the same binding site on the bacterial surface. These results can be exploited in developing a new approach for detoxification of mycotoxins from foods and feeds.