Microbial degradation of DON and ZEN in animal feed to reduce carryover from animals to humans

Aflatoxins (AF), zearalenone (ZEN), fumonisins (FB₁ and FB₂), T-2/HT-2 toxins, ochratoxin A (OTA), and deoxynivalenol (DON) are considered the most economically important mycotoxins in terms of their high prevalence and significant negative effects on animal performance.

DON is a type B trichothecene mycotoxin and ZEN is a potent estrogenic metabolite produced by several Fusarium species that infest maize, wheat, barley, and oats.

Food and animal feed co-contaminated with DON and ZEN present a significant health risk for livestock and can enter humans via livestock-based foods.

Among many remediation methods in animals, biological degradation of mycotoxins has shown promise because it works under mild and environmental friendly conditions.

In this research work, 5 soil samples were collected from different fields of alfalfa crop and pooled into one sample.

The microbe identified as Devosia lucknowensis by NCIMB (UK) was isolated through an enrichment culture procedure using a mineral salt medium and 1 ppm of DON as a sole carbon source.

D. lucknowensis degraded 100% of DON in a 24-hour period at 30°C and under aerobic conditions.

For the isolation of the ZEN-degrading microbe Aerobium tamlense, a soil sample was collected from a field of wheat and contaminated with ZEN-rich material.

Samples were taken every six days and, after it was determined that the level of ZEN had been decreasing in a span of 2 months, an enrichment culture procedure was started using a mineral salt medium and 1 ppm of ZEN as a sole carbon source.

A. tamlensedegraded 100% of ZEN in a 2-hour period at and under aerobic conditions.

The reduction in the level of DON and ZEN was quantified through LC-MS/MS.

D. lucknowensis was able to reduce DON at pH levels ranging from 6 to 9 and temperatures of 30-40°C.

A. tamlense was able to reduce ZEN at pH levels ranging from 4 to 9 and temperatures of 30-40°C.

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