Microbial Degradation of Zearalenone by a Novel Microbial Consortium, NZDC-6, and Its Application on Contaminated Corncob by Semisolid Fermentation

A novel microbial consortium (NZDC-6)
was screened and characterized
to detoxify the estrogenic mycotoxin zearalenone (ZEA), which commonly
contaminates maize and is a major threat to food and health security.
We found NZDC-6 to be thermophilic and highly effective, with a 90.3%
ZEA degradation ratio at an optimum temperature of 60 °C. NZDC-6
was also effective at degrading the more estrogenic ZEA cognates,
α-zearalenol (α-ZAL) and β-zearalenol (β-ZAL),
with >90% degradation ratios. To evaluate a practical application,
ZEA-contaminated corncobs were treated with NZDC-6 via semisolid fermentation.
Measurements of physicochemical parameters and 16S microbial diversity
and redundancy analysis (RDA) indicated that ZEA removal was most
efficient at a low corncob solid content (< 5%), as a high solid
content overwhelmed the microbial metabolic load, leading to increased
dissolved oxygen and lowered pH. Our results demonstrate that the
control of environmental variables is crucial for effective ZEA microbial
removal in practical applications.