timosaponin B-II

• 分子结构分类: 有机化合物 - 脂质和类脂质分子 - 类固醇和类固醇衍生物
• 英文名称: timosaponin B-II
• 英文别名: (2R,3R,4S,5S,6R)-2-[(2S)-4-[(1R,2S,4S,6S,7S,8R,9S,12S,13S,16S,18R)-16-[(2R,3R,4S,5R,6R)-4,5-dihydroxy-6-(hydroxymethyl)-3-[(2S,3R,4S,5S,6R)-3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]oxyoxan-2-yl]oxy-6-hydroxy-7,9,13-trimethyl-5-oxapentacyclo[10.8.0.02,9.04,8.013,18]icosan-6-yl]-2-methylbutoxy]-6-(hydroxymethyl)oxane-3,4,5-triol
• 化学式: C₄₅H₇₆O₁₉
• 分子量: 921.087
• InChiKey: SORUXVRKWOHYEO-IEEWBPOCSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  0.7
• 重原子数：
  64
• 可旋转键数：
  13
• 环数：
  8.0
• sp3杂化的碳原子比例：
  1.0
• 拓扑面积：
  307
• 氢给体数：
  12
• 氢受体数：
  19

反应信息

• 作为反应物：
  描述：

  timosaponin B-II 、 starch 以 citrated phosphate buffer 为溶剂， 生成 (22S,25S)-26-O-β-D-glucopyranosyl-22-hydroxy-5β-furost-3β,26-diol-3-O-α-D-glucopyranosyl-(1->4)-β-D-glucopyranosyl-(1->2)-β-D-galactopyranoside 、 (22S,25S)-26-O-α-D-glucopyranosyl-(1->4)-β-D-glucopyranosyl-22-hydroxy-5β-furost-3β,26-diol-3-O-β-D-glucopyranosyl-(1->2)-β-D-galactopyranoside
  参考文献：
  名称：

  Enzymatic synthesis of α-glucosyl-timosaponin BII catalyzed by the extremely thermophilic enzyme: Toruzyme 3.0L

  摘要：

  Timosaponin BII (BII), a steroidal saponin showing potential anti-dementia activity, was converted into its glucosylation derivatives by Toruzyme 3.0L. Nine products with different degrees of glucosylation were purified and their structures were elucidated on the basis of C-13 NMR, HR-ESI-MS, and FAB-MS spectra data. The active enzyme in Toruzyme 3.0L was purified to electrophoretic homogeneity by tracking BII-glycosylase activity and was identified as Cyclodextrin-glycosyltransferase (CGTase, EC 2.4.1.19) by ESI-Q-TOF MS/MS. In this work, we found that the active enzyme catalyzed the synthesis of alpha-(1 -> 4)-linked glucosyl-BII when dextrin instead of an expensive activated sugar was used as the donor and showed a high thermal tolerance with the most favorable enzymatic activity at 100 degrees C. In addition, we also found that the alpha-amylases and CGTase, that is, GH13 family enzymes, all exhibited similar activities, which were able to catalyze glucosylation in steroidal saponins. But other kinds of amylases, such as gamma-amylase (GH15 family), had no such activity under the same reaction conditions. (C) 2010 Elsevier Ltd. All rights reserved.

  DOI：

  10.1016/j.carres.2010.05.027

文献信息

• Enzymatic synthesis of α-glucosyl-timosaponin BII catalyzed by the extremely thermophilic enzyme: Toruzyme 3.0L
  作者：Wen-bin Zhou、Bing Feng、Hong-zhi Huang、Yu-juan Qin、Yong-ze Wang、Li-ping Kang、Yang Zhao、Xiao-nan Wang、Yun Cai、Da-wei Tan、Bai-ping Ma

  DOI：10.1016/j.carres.2010.05.027

  日期：2010.8

  Timosaponin BII (BII), a steroidal saponin showing potential anti-dementia activity, was converted into its glucosylation derivatives by Toruzyme 3.0L. Nine products with different degrees of glucosylation were purified and their structures were elucidated on the basis of C-13 NMR, HR-ESI-MS, and FAB-MS spectra data. The active enzyme in Toruzyme 3.0L was purified to electrophoretic homogeneity by tracking BII-glycosylase activity and was identified as Cyclodextrin-glycosyltransferase (CGTase, EC 2.4.1.19) by ESI-Q-TOF MS/MS. In this work, we found that the active enzyme catalyzed the synthesis of alpha-(1 -> 4)-linked glucosyl-BII when dextrin instead of an expensive activated sugar was used as the donor and showed a high thermal tolerance with the most favorable enzymatic activity at 100 degrees C. In addition, we also found that the alpha-amylases and CGTase, that is, GH13 family enzymes, all exhibited similar activities, which were able to catalyze glucosylation in steroidal saponins. But other kinds of amylases, such as gamma-amylase (GH15 family), had no such activity under the same reaction conditions. (C) 2010 Elsevier Ltd. All rights reserved.