Mycoestrogens are estrogens produced by fungi. The most important mycoestrogen is zearalenone

Zearalenone

Zearalenone , also known as RAL and F-2 mycotoxin, is a potent estrogenic metabolite produced by some Gibberella species.Several Fusarium species produce toxic substances of considerable concern to livestock and poultry producers: namely, deoxynivalenol, T-2 toxin, HT-2 toxin, diacetoxyscirpenol ...

, produced by Fusarium

Fusarium

Fusarium is a large genus of filamentous fungi widely distributed in soil and in association with plants. Most species are harmless saprobes, and are relatively abundant members of the soil microbial community. Some species produce mycotoxins in cereal crops that can affect human and animal health...

 species of fungi. Zearalenone is the main phyto-oestrogen consumed in the USA. It may be one dietary factor that can reduce the prevalence of breast cancer.

In Food

Mycoestrogens are commonly found in stored grain. They can come from fungi growing on the grain as it grows, or after harvest during storage. Mycoestrogens can be found in silage

Silage

Silage is fermented, high-moisture fodder that can be fed to ruminants or used as a biofuel feedstock for anaerobic digesters. It is fermented and stored in a process called ensiling or silaging, and is usually made from grass crops, including corn , sorghum or other cereals, using the entire...

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