%0 Journal Article
%T C-ring cleavage of isoflavone daidzein by a newly-isolated facultative Enterococcus hirae AUH-HM195 from crossoptilon mantchuricum feces?<br>兼性肠球菌Enterococcus hirae AUH-HM195对黄豆苷原的开环转化
%A Fei Yu
%A Shiying Wang
%A Jia Li
%A Qi Zhang
%A Chaodong Li
%A Xiuling Wang
%A <br>于飞
%A 王世英
%A 李佳
%A 张琪
%A 李朝东
%A 王秀伶
%J 微生物学报
%D 2009
%I 
%X Abstract: Objective] To isolate specific bacteria capable of biotransforming isoflavone daidzein. Methods] Fresh crossoptilon mantchuricum feces was diluted serially from 10-1 to 10-8 in Brain Heart Infusion (BHI)liquid medium in the anaerobic chamber at 37?C. Single colony was isolated and incubated in BHI liquid medium containing 0.1mmol/L daidzein under anaerobic conditions. The culture medium was detected by HPLC method after being incubated for 3 days. Results] A gram-positive facultative anaerobic bacterium designated strain AUH-HM195 capable of cleaving the C-ring of isoflavone daidzein was isolated. Basic Local Alignment Search Tool (BLAST) search on the GenBank revealed that the full-length of 16S rDNA gene sequence for strain AUH-HM195 has 100% similarity to that of Enterococcus hirae (DSM20160). Based on HPLC retention time, UV spectrum, 1H and 13C NMR analysis, the metabolite of daidzein by strain Enterococcus hirae AUH-HM195 was identified as O-desmethylangolensin. Two peaks were observed when purified O-desmethylangolensin was eluted on a chiral column. The enantiomeric excess (% e.e.) of O-desmethylangolensin was 66.9%. Conclusion] Bacterial strain Enterococcus hirae AUH-HM195 is the first reported Enterococcus bacterium with C-ring cleavage activity. It is also the first reported facultative bacterium capable of metabolizing isoflavones.
%K Keywords: isoflavones
%K daidzein
%K biotransformation
%K O-desmethylangolensin
%K isolation<br>关键词：大豆异黄酮
%K 黄豆苷原
%K 生物转化
%K 去氧甲基安哥拉紫檀素
%K 筛选
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=90BA3D13E7F3BC869AC96FB3DA594E3FE34FBF7B8BC0E591&jid=A3C6BA55AB623B90FA9104CFFC826F3C&aid=948192BC17BCA68E05498FCFF61EF68F&yid=DE12191FBD62783C&vid=2A3781E88AB1776F&iid=E158A972A605785F&sid=A33A8FD1432A4C3E&eid=D8B37A0210DB6B9D&journal_id=0001-6209&journal_name=微生物学报&referenced_num=1&reference_num=22