Enzymatic biosynthesis of novel neobavaisoflavone glucosides via Bacillus UDP-glycosyltransferase  

作　　者：MA Tao DAI Yi-Qun LI Nan HUO Qiang LI Hong-Mei ZHANG Yu-Xin PIAO Zheng-Hao WU Cheng-Zhu 

机构地区：[1]School of Pharmacy,Bengbu Medical College,Bengbu 233030,China [2]Department of Biochemistry,Bengbu Medical College,Bengbu 233030,China [3]Department of Basic Medical Science,School of Medicine,Hangzhou Normal University,Hangzhou 321004,China

出　　处：《Chinese Journal of Natural Medicines》2017年第4期281-287,共7页中国天然药物（英文版）

基　　金：financially supported by National Natural Science Foundation of China(No.81302671);the Education Department of Anhui Natural Science Research Project China(No.KJ2015A273);Zhejiang Provincial Natural Science Foundation of China(No.LY13H10004)

摘　　要：The present study was designed to perform structural modifications of of neobavaisoflavone(NBIF), using an in vitro enzymatic glycosylation reaction, in order to improve its water-solubility. Two novel glucosides of NBIF were obtained from an enzymatic glycosylation by UDP-glycosyltransferase. The glycosylated products were elucidated by LC-MS, HR-ESI-MS, and NMR analysis. The HPLC peaks were integrated and the concentrations in sample solutions were calculated. The MTT assay was used to detect the cytotoxic activity of compounds in cancer cell lines. Based on the spectroscopic analyses, the two novel glucosides were identified as neobavaisoflavone-4′-O-β-D-glucopyranoside(1) and neobavaisoflavone-4′, 7-di-O-β-D-glucopyranoside(2). Additionally, the water-solubilities of compounds 1 and 2 were approximately 175.1-and 4 031.9-fold higher than that of the substrate, respectively. Among the test compounds, only NBIF exhibited weak cytotoxicity against four human cancer cell lines, with IC50 values ranging from 63.47 to 72.81 μmol·L^(-1). These results suggest that in vitro enzymatic glycosylation is a powerful approach to structural modification, improving water-solubility.The present study was designed to perform structural modifications of of neobavaisoflavone（NBIF）, using an in vitro enzymatic glycosylation reaction, in order to improve its water-solubility. Two novel glucosides of NBIF were obtained from an enzymatic glycosylation by UDP-glycosyltransferase. The glycosylated products were elucidated by LC-MS, HR-ESI-MS, and NMR analysis. The HPLC peaks were integrated and the concentrations in sample solutions were calculated. The MTT assay was used to detect the cytotoxic activity of compounds in cancer cell lines. Based on the spectroscopic analyses, the two novel glucosides were identified as neobavaisoflavone-4′-O-β-D-glucopyranoside（1） and neobavaisoflavone-4′, 7-di-O-β-D-glucopyranoside（2）. Additionally, the water-solubilities of compounds 1 and 2 were approximately 175.1-and 4 031.9-fold higher than that of the substrate, respectively. Among the test compounds, only NBIF exhibited weak cytotoxicity against four human cancer cell lines, with IC50 values ranging from 63.47 to 72.81 μmol·L^（-1）. These results suggest that in vitro enzymatic glycosylation is a powerful approach to structural modification, improving water-solubility.

关 键 词：Neobavaisoflavone GLYCOSYLATION UDP-glycosyltransferase WATER-SOLUBILITY Cytotoxicity 

分 类 号：R917[医药卫生—药物分析学]