Microbial Transformation of Zearalenone, I. Formation of Zearalenone-4-O-β-glucoside

Abstract

Zearalenone is a natural mycotoxin produced by a number of Fusarium species, particularly F. mswm (gramiwnrm) and F. tririnrtrrm (1)(2)(3)(4). This compound has been associated with a hyperestrogenic syndrome causing serious problems when fed to many classes of livestock (6,7). The diseased animals show signs of genital disorders involving vulvovaginitis, edematous uterus, and overian atrophy (7). In addition, it was reported (5-9) that zearalenone and some of its derivatives have anabolic effects and are currently used as growth promoters. The screening of 150 microorganisms for transformation ofzearalenone showed several metabolites including a-and p-zearalenone, and 8-zearalanol. The present communication describes studies related to the bioconversion of zearalenone to zearalenone glucoside by Thamnidium elegans and M w w bainieri.Small-scale experiments with 150 fungi showed that only two cultures produced a unique metabolite that had a low Rfvalue that was obtained in considerable yields by T . eIegans (60%) and M . baineiri (30%). Large-scale fermentations with T. eleguns were carried out to obtain sufficient quantities of the metabolite for structure elucidation. The metabolite was identified as zearalenone-4-0-p-glucoside on the basis of ir, nmr, and mass spectral analysis. After this report was submitted for publication, Kamimura (10) reported the structure of zearalenone-4-0-@-glucoside produced through microbial conversion of zearalenone by a species of Rhizopus, and the spectral data supporting the structure can be found in that reference. EXPERIMENTALMelting points were determined on a Fisher-Jones hot plate apparatus and are uncorrected. Ir spectra were taken with a Perkin-Elmer 281 spectrophotometer using nujol discs. High resolution mass spectra were determined on an LKB 9000 GC mass spectrometer. Nmr were taken in CDCI, or acetone-d6 using TMS as an internal standard. 'H nmr and CL3 nmr were taken on a 300 MHz Nicolet NT-3OO-W3 spectrometer.'This material is from a

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

“…In some other studies, transformation of ZEN by microorganisms to more-potent estrogenic zearalenols has been observed (1,7,14,16). This indicates that biodegradation of ZEN by bacteria is not a suitable approach to detoxify ZEN and its derivatives.…”

“…El-Sharkawy et al (7) investigated the conversion of ZEN by seven genera (23 species) of microorganisms. The metabolites formed included ␣-ZOL and ␤-ZOL and another polar metabolite, zearalenone-4-O-sulfate.…”

Evolution of Chemical Diversity in Echinocandin Lipopeptide Antifungal Metabolites

“…The sulfation step may simply represent a coincidental biotransformation reaction absent in the ancestral echinocandin pathway. In vitro sulfation of aromatic phenols has been occasionally reported in the Fungi (84)(85)(86)(87). Although the mechanism of the pneumocandin homotyrosine sulfation remains to be elucidated, the putative aryl sulfotransferase identified in P. cf.…”

Biodegradation of aflatoxin-B1 and zearalenone by Streptomyces sp. collection

“…(ASBV-1) and in addition, the strain was able to prevent aflatoxin production (Zucchi et al, 2008). Furthermore, several strains like Streptomyces griseus (ATTC 13273) and Streptomyces rutgersensis (NRRL-B 1256) were able to degrade zearalenon mycotoxin directly (El-Sharkawy and Abul-Hajj, 1987). However, the loss of estrogenicity was not detected in any case.…”