文献类型：期刊文献

英文题名：Identification, purification and characterization of β-glucosidase from apple seed as a novel catalyst for synthesis of O-glucosides

作者：Yu, Hui-Lei[1]; Xu, Jian-He[1]; Lu, Wen-Ya[2]; Lin, Guo-Qiang[2]

机构：[1] Laboratory of Biocatalysis and Bioprocessing, State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, P.O. Box 283, Shanghai, 200237, China; [2] Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, 200032, China

年份：2007

卷号：40

期号：2

起止页码：354

外文期刊名：Enzyme and Microbial Technology

收录：EI(收录号：20064710263359)

语种：英文

外文关键词：Catalysts - Fruits - Hydrolysis - Purification - Seed - Synthesis (chemical) - Thermodynamic stability

摘要：Among several fruit seeds, apple seed was identified as a new promising β-glucosidase source for alkyl O-glucoside synthesis by reverse hydrolysis, since it showed high hydrolytic activities on a broad spectrum of β-glucosides. From the crude extract of apple seed meal, a major glucosidase isoenzyme was purified to homogeneity, with a purification factor of 47-fold and an overall yield of 12.8%, by ammonium sulfate fractionation and chromatographic separation through DEAE-Cellulose, Butyl-Toyopearl and Sephadex G150 columns. The purified enzyme is a homodimer; each subunit has a molecular mass of about 60 kDa as determined by SDS-polyacrylamide gel electrophoresis (SDS-PAGE) and the pI of this β-glucosidase is about 5.7. These properties indicate that the apple seed β-glucosidase is totally different from any of the almond β-glucosidase isozymes reported so far. Furthermore, the purified enzyme of apple seed displays higher thermal stability than the commercially supplied β-glucosidase from almond, with half-lives of 42.9 h and 14.2 h, respectively, as preserved at 50 °C in an aqueous environment. The optimum pH of the apple seed β-glucosidase was 6.0 and the stable pH range was 5.0-9.0, both similar to those of the commercial almond β-glucosidase. ? 2006 Elsevier Inc. All rights reserved.