Biotransformation of the mycotoxin, zearalenone, to a non-estrogenic compound by a fungal strain of Clonostachys sp.

Zearalenones are mycotoxins with estrogenic activity consisting of a resorcinol moiety fused to a 14-membered macrocyclic lactone and are produced by various Fusarium species. We found that Clonostachys rosea IFO 7063 was effectively capable of converting zearalenone (1) to cleavage product (2), 1-(3,5-dihydroxyphenyl)-10'-hydroxy-1'E-undecene-6'-one. Moreover, cleavage product 2 did not show potent estrogenic activity like that of 1 and 17beta-estradiol in the human breast cancer MCF-7 cell proliferation assay.