Binding rather than metabolism may explain the interaction of two food-Grade Lactobacillus strains with zearalenone and its derivative (')alpha-earalenol.
The interaction between two Fusarium mycotoxins, zearalenone (ZEN) and its derivative (')alpha-zearalenol ((')alpha-ZOL), with two food-grade strains of Lactobacillus was investigated. The mycotoxins (2 microg 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 (')alpha-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 (')alpha-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 (')alpha-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.
El-Nezami
Hani
H
Department of Clinical Nutrition, Food and Health Research Center, PO Box 1627, University of Kuopio, FIN-70211 Kuopio, Finland. Hani.El-nezami@uku.fi
Polychronaki
Nektaria
N
Salminen
Seppo
S
Mykkänen
Hannu
H
D000348:Aflatoxins / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid; D004968:Estrogens, Non-Steroidal / Q000378:metabolism*; D007778:Lactobacillus / Q000378:metabolism*; D014255:Trichothecenes / Q000378:metabolism; D015025:Zearalenone / Q000378:metabolism*; D015029:Zeranol / Q000031:analogs & derivatives* / Q000378:metabolism*
D000348:Aflatoxins; D004968:Estrogens, Non-Steroidal; D014255:Trichothecenes; C029659:zearalenol; D015025:Zearalenone; D015029:Zeranol