title: Immobilization of proline-specific endoprotease on nonporous silica nanoparticles functionalized with amino group.
abstract: Enzyme immobilization is believed to provide an excellent base for increasing environmental tolerance of enzyme and considerable period of time. In this work, a kind of nonporous silica nanoparticles functionalized with amino group was synthesized to immobilize proline-specific endoprotease (PSEP). PSEP is known to specifically cleave peptides (or esters) at the carboxyl side of proline, thus can prevent the formation of haze and prolong the shelf life of beer. After immobilization, the environmental tolerance (temperature and pH, respectively) was obviously improved, and the immobilized enzyme can retain above 90 % of its original activity after 6 uses. Moreover, the immobilized enzyme can effectively prevent the formation of chill-haze using fresh beer fermentation liquid.
authors.affiliation: State Key Laboratory of Biological Fermentation Engineering of Beer, Tsingtao Brewery Co., Ltd, Qingdao, 266100, People's Republic of China.|Key Laboratory of Bio-based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, Shandong Province, People's Republic of China.
authors.forename: Fuhua
authors.initials: F
authors.lastname: Zhao
authors.affiliation: Key Laboratory of Bio-based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, Shandong Province, People's Republic of China. houtg@qibebt.ac.cn.
authors.forename: Tonggang
authors.initials: T
authors.lastname: Hou
authors.affiliation: Key Laboratory of Bio-based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, Shandong Province, People's Republic of China.
authors.forename: Jianxun
authors.initials: J
authors.lastname: Wang
authors.affiliation: Key Laboratory of Bio-based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, Shandong Province, People's Republic of China.
authors.forename: Yijun
authors.initials: Y
authors.lastname: Jiang
authors.affiliation: State Key Laboratory of Biological Fermentation Engineering of Beer, Tsingtao Brewery Co., Ltd, Qingdao, 266100, People's Republic of China.
authors.forename: Shuxia
authors.initials: S
authors.lastname: Huang
authors.affiliation: Key Laboratory of Bio-based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, Shandong Province, People's Republic of China.
authors.forename: Qiao
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Key Laboratory of Bio-based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, Shandong Province, People's Republic of China.
authors.forename: Mo
authors.initials: M
authors.lastname: Xian
authors.affiliation: Key Laboratory of Bio-based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, Shandong Province, People's Republic of China. muxd@qibebt.ac.cn.
authors.forename: Xindong
authors.initials: X
authors.lastname: Mu
mesh_terms: D001234:Aspergillus niger / Q000201:enzymology*; D004800:Enzymes, Immobilized / Q000737:chemistry; D005656:Fungal Proteins / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D053758:Nanoparticles / Q000737:chemistry*; D016062:Porosity; D000085822:Prolyl Oligopeptidases; D012697:Serine Endopeptidases / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry*
chemical_list: D004800:Enzymes, Immobilized; D005656:Fungal Proteins; D012822:Silicon Dioxide; D012697:Serine Endopeptidases; D000085822:Prolyl Oligopeptidases
keywords: Beer; Chill-haze; Enzymatic activity; Enzyme immobilization; Proline-specific endoprotease