High serum S-equol content in red clover fed ewes: the classical endocrine disruptor is a single enantiomer

Eeva A. Mustonen, Tuija Jokela, Ilkka Saastamoinen, Juhani Taponen, Suvi Taponen, Hannu Saloniemi, Kristiina Wähälä

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An expedient high performance liquid chromatography (HPLC) method was developed for the quantitative analysis of environmental estrogenic isoflavonoids, particularly (S)-equol, in red clover fed ewes. We report here the phytoestrogen analysis of red clover silage and the serum of ewes fed with this feed. Ewes received daily 10.5 g of formononetin on average from red clover silage. In the serum samples a major part of formononetin had been metabolised to equol (average 7.7 mu g ml(-1)). According to chiral HPLC analysis, the equol present in the serum of ewes was solely of the (S)-form. We also demonstrate the presence of the metabolite O-demethylangolensin (O-DMA) in ovine serum.
Original languageEnglish
JournalEnvironmental Chemistry Letters
Issue number4
Pages (from-to)154-159
Number of pages6
Publication statusPublished - 2006
MoE publication typeA1 Journal article-refereed

Fields of Science

  • 413 Veterinary science
  • lammas
  • puna-apila
  • flavonoidit
  • kasviestrogeenit
  • 116 Chemical sciences

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