文献类型：期刊文献

英文题名：Enzymatic transformation of ginsenoside Rg3 to Rh2 using newly isolated Fusarium proliferatum ECU2042

作者：Su, Jin-Huan[1]; Xu, Jian-He[1,3]; Lu, Wen-Ya[2]; Lin, Guo-Qiang[2,3]

机构：[1] Laboratory of Biocatalysis and Bioprocessing, State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China; [2] Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China; [3] Laboratory of Biocatalysis and Bioprocessing, State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China

年份：2006

卷号：38

期号：2

起止页码：113

外文期刊名：Journal of Molecular Catalysis B: Enzymatic

收录：EI(收录号：2006049666225)

语种：英文

外文关键词：Biosynthesis - Fermentation - Hydrolysis - pH - Rhodium - Soils

摘要：A new soil isolate, Fusarium proliferatum ECU2042, was found capable of producing a ginsenoside Rg3 hydrolase (a special β-glucosidase) which is useful for production of a very potent antitumor agent Rh2. By investigating its fermentation progress, the optimal time for β-glucosidase biosynthesis was determined as 72 h. The crude β-glucosidase was partially purified by 49.4-fold from the cell-free extract with an activity yield of 13%. The catalytic performance of the partially purified β-glucosidase was examined, giving optima of pH and temperature at pH 5.0-6.0 and 50°C. It was found that the F. proliferatum β-glucosidase can also hydrolyze cellobiose, but not active towards a frequently used artificial substrate p-nitrophenyl β-d-glucopyranoside (pNPG). In a lab-scale preparation, the bio-hydrolytic reaction was carried out at 50°C for 24 h in 50 ml NaAc/HAc buffer (100 mM, pH 5.0) containing 50 mg Rg3 and 12 mg lyophilized crude enzyme extract, giving the ginsenoside Rh2 in 60.3% conversion. ? 2005 Elsevier B.V. All rights reserved.