ABSTRACT

1. The aim of this study was to evaluate the production of equol (4ʹ,7-isoflavandiol; a bacterial polyphenol metabolite which is an isoflavandiol oestrogen metabolised from daidzein from plants) enriched eggs from free-range hens fed different pasture species. Four species were tested: red clover, white clover, ryegrass and chicory.

2. The study was conducted from June to September 2017 on eight free range, outdoor areas, each containing fifteen laying hens and sown with a single pasture species

3. Precursors of equol (daidzein, formononetin) were analysed every fortnight from the fresh pasture cover in each area, as well as equol and daidzein levels in eggs.

4. Daidzein and formononetin concentrations in the fresh pasture samples differed significantly according to species (P < 0.001), whereby red clover had the highest concentrations of daidzein and formononetin (85 and 996 µg/g DM, respectively).

5. Equol concentration in eggs differed according to pasture species (P < 0.001). Equol concentrations reached about 1,200 ng/g DM in eggs from hens with access to red clover. These eggs can represent a valuable source of equol in the human diet.

摘要

1. 本研究的目的是评估雌马酚（4ʹ,7-异黄烷二醇；一种细菌多酚代谢物，它是一种从植物中的黄豆苷元中代谢的异黄烷二醇雌激素）富含不同牧草种类的散养母鸡的鸡蛋的产量。测试了四个物种：红三叶草、白三叶草、黑麦草和菊苣。

2. 该研究于 2017 年 6 月至 9 月在八个自由放养的户外区域进行，每个区域包含 15 只蛋鸡并播种单一牧草品种

3. 每两周从每个地区的新鲜牧草覆盖物中分析雌马酚前体（黄豆苷元、芒柄花素），以及鸡蛋中的雌马酚和黄豆苷元水平。

4. 新鲜牧草样品中黄豆苷元和芒柄花素的浓度因品种而异（P < 0.001），其中红三叶的黄豆甙元和芒柄花素浓度最高（分别为 85 和 996 µg/g DM）。

5. 鸡蛋中雌马酚浓度因牧草种类而异（P < 0.001）。使用红三叶草的母鸡产蛋中的雌马酚浓度达到约 1,200 ng/g DM。这些鸡蛋可以代表人类饮食中宝贵的雌马酚来源。