Yu Zhuo-Teng, Yao Wen, Zhu Wei-Yun
College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China.
FEMS Microbiol Lett. 2008 May;282(1):73-80. doi: 10.1111/j.1574-6968.2008.01108.x. Epub 2008 Mar 4.
Transformation of daidzein to equol was compared during fermentation of three growth media inoculated with faeces from Erhualian piglets, but equol was produced from only one medium, M1. Two equol-producing strains (D1 and D2) were subsequently isolated using medium M1. Both strains were identified as Eubacterium sp., on the basis of morphological and physiological characteristics, and 16S rRNA gene sequence analysis showed that strains D1 and D2 were most closely related to previously characterized daidzein-metabolizing bacteria isolated from human faecal and rumen samples, respectively. This suggests that the ability to metabolize daidzein can be found among bacteria present within the mammalian intestine. The results provided the first account of conversion of daidzein directly to equol by bacterial species from farm animals. These strains may be of importance to the improvement of animal performance, and the use of medium M1 could provide a simple way to isolate bacterial strains capable of transforming daidzein into equol.
在接种二花脸仔猪粪便的三种生长培养基发酵过程中，比较了大豆苷元向雌马酚的转化情况，但仅在一种培养基M1中产生了雌马酚。随后使用培养基M1分离出两株产雌马酚菌株（D1和D2）。根据形态学和生理学特征，这两株菌株均被鉴定为真杆菌属，16S rRNA基因序列分析表明，菌株D1和D2分别与先前从人类粪便和瘤胃样本中分离出的具有大豆苷元代谢能力的细菌关系最为密切。这表明在哺乳动物肠道内的细菌中可以发现代谢大豆苷元的能力。该结果首次报道了农场动物来源的细菌物种将大豆苷元直接转化为雌马酚的情况。这些菌株可能对改善动物性能具有重要意义，并且使用培养基M1可以提供一种简单的方法来分离能够将大豆苷元转化为雌马酚的细菌菌株。
