@article{oai:toyama.repo.nii.ac.jp:00005299,
 author = {MESELHY, MeselhyR. and Nishimoto, Eri and Akao, Teruaki and Hattori, Masao},
 issue = {2},
 journal = {和漢医薬学雑誌 = Journal of traditional medicines},
 month = {Apr},
 note = {application/pdf, For the purpose of investigating the metabolic processes of shikonin (1) by human intestinal bacteria, we prepared a sonicated bacterial cell suspension and a crude enzyme preparation from Eubacterium sp. A-44, one of the intestinal bacteria capable of transforming 1 to various metabolites. After anaerobic incubation with the suspension for 1 hr, most of 1 was transformed to prometaboshi-konin (2), and metaboshikonins I (3) and II (4). However, under aerobic conditions, the dimers, shikometabolins A (5) and B (6), were predominantly formed. In the presence of the crude enzyme preparation, formation of 2-4 was inhibited by oxygen, but markedly enhanced by the addition of NADH. On the other hand, formation of 5 and 6 was appreciably accelerated by the addition of NAD^+. In the absence of the crude enzyme preparation, NADH and/or NAD^+ showed no ability to transform 1 to the any metabolites, as in the case of a thermally inactivated preparation. Accordingly, the two different metabolic processes leading to compounds 2-4 and com-pounds 5 and 6 by Eubacterium sp. A-44 are concluded to be enzyme-dependent in the presence of NADH and NAD^+.
 ヒト腸内細菌による紫根成分shikoninの代謝過程を研究する目的でshikonin(1)を種々の代謝物に変換する腸内細菌Eubacterium sp.A-44の細胞破砕懸濁液及び粗酵素標品を調製した。この粗酵素標品とshikonin(1)を嫌気条件下で1時間インキュベーションすると,shikonin(1)のほとんどはprometaboshikonin(2)およびmetaboshikonin I(3),II(4)に変換された。しかしながら,好気条件下ではshikometabolin A(5),B(6)などの二量体が生成した。化合物2-4の生成は,酸素によって阻害され,NADHの添加により増強した。一方,化合物5,6の生成はNAD^+の添加により増加した。加熱処理した場合と同様,粗酵素標品を除去した場合は,NADH,NAD^+を添加してもshikoninの変換は起こらなかった。したがって,NADHやNAD^+の存在下での化合物2-4や化合物5,6への変換過程は酵素反応によって触媒されることを示している。, Article},
 pages = {58--63},
 title = {Transformation of shikonin by a cell-free extract of Eubacterium sp. A-44, a human intestinal bacterium},
 volume = {18},
 year = {2001}
}