Shaanxi Engineering Center of Bioresource Chemistry & Sustainable Utilization, College of Science, Northwest A & F University, Yangling 712100, Shaanxi, People's Republic of China.
J Nat Prod. 2011 Oct 28;74(10):2095-101. doi: 10.1021/np2003484. Epub 2011 Oct 10.
Microbial transformation of diosgenin (3β-hydroxy-5-spirostene) using white-rot fungus Coriolus versicolor afforded four previously unreported polyhydroxylated steroids, 25(R)-spirost-5-en-3β,7α,15α,21-tetraol (5), 25(R)-spirost-5-en-3β,7β,12β,21-tetrol (6), (25R)-spirost-5-en-3β,7α,12β,21-tetraol (7), and (25R)-spirost-5-en-3β,7β,11α,21-tetraol (8), along with three known congeners, 25(R)-spirost-5-en-3β,7β-diol (2), 25(R)-spirost-5-en-3β,7β,21-triol (3), and 25(R)-spirost-5-en-3β,7β,12β-triol (4). These structures were elucidated by 1D and 2D NMR as well as HR-ESIMS analysis. In addition, we provide evidence for two new microbial hydroxylations of diosgenin: C-21 primary carbon hydroxylation and C-15 hydroxylation. The 3β-hydroxyl group and double bond in the B-ring of diosgenin were found to be important structural determinants for their activity.
利用白腐真菌云芝对薯蓣皂苷元（3β-羟基-5-螺甾烯）进行微生物转化，得到了四个以前未报道的多羟基甾体，25(R)-螺甾-5-烯-3β,7α,15α,21-四醇（5）、25(R)-螺甾-5-烯-3β,7β,12β,21-四醇（6）、(25R)-螺甾-5-烯-3β,7α,12β,21-四醇（7）和(25R)-螺甾-5-烯-3β,7β,11α,21-四醇（8），以及三个已知的同系物，25(R)-螺甾-5-烯-3β,7β-二醇（2）、25(R)-螺甾-5-烯-3β,7β,21-三醇（3）和 25(R)-螺甾-5-烯-3β,7β,12β-三醇（4）。这些结构通过 1D 和 2D NMR 以及高分辨率电喷雾电离质谱（HR-ESIMS）分析得到了阐明。此外，我们还提供了薯蓣皂苷元的两种新的微生物羟基化反应的证据：C-21 伯碳羟基化和 C-15 羟基化。薯蓣皂苷元的 3β-羟基和 B 环中的双键被发现是其活性的重要结构决定因素。
