Department of Pharmaceutical Sciences, College of Pharmacy, Chicago State University, 9501 S. King Drive, Chicago, IL 60628, USA.
Bioorg Med Chem. 2012 May 1;20(9):2784-8. doi: 10.1016/j.bmc.2012.03.046. Epub 2012 Mar 29.
Microbial transformation of silybin (1), the major flavonolignan of milk thistle (Silybum marianum, Asteraceae), resulted in the isolation of four metabolites. The structures of the isolated metabolites were determined by spectroscopic methods. One phase I metabolite was produced by Beauveria bassiana and was characterized as 8-hydroxysilybin (2). Three phase II metabolites were produced by two Cunninghamella species and were identified as 2,3-dehydrosilybin-3-O-β-d-glucoside (3), obtained from Cunninghamella species; and silybin-7-sulfate (4) and 2,3-dehydrosilybin-7-sulfate (5), obtained from Cunninghamella blakesleana. Compared to 1 (IC(50) 284 μg/mL), the generated metabolites displayed varying levels of antioxidant activities in the DPPH free-radical scavenging assay.
水飞蓟宾（1）是奶蓟草（菊科水飞蓟属植物）中的主要黄酮木脂素，经微生物转化后分离得到了 4 种代谢产物。通过光谱方法确定了分离出的代谢产物的结构。一种 I 相代谢产物由淡紫拟青霉产生，被鉴定为 8-羟基水飞蓟宾（2）。两种新月弯孢霉产生了 3 种 II 相代谢产物，分别鉴定为 2,3-脱水水飞蓟宾-3-O-β-D-葡萄糖苷（3）；以及水飞蓟宾-7-硫酸盐（4）和 2,3-脱水水飞蓟宾-7-硫酸盐（5）。与 1 相比（IC50 284 μg/mL），生成的代谢产物在 DPPH 自由基清除试验中表现出不同程度的抗氧化活性。
