title: Characteristics of pectinase treated with ultrasound both during and after the immobilization process.
abstract: In this study, ultrasound was applied both during and after the immobilization process and characteristics of different immobilized pectinase samples were studied. When introduced during the immobilization process, ultrasound at an intensity of 9WmL-1for 20min increased the immobilization yield 92.28% more than the control. When introduced to the already immobilized pectinase, ultrasound at an intensity of 4.5WmL-1for 10min increased the pectinase activity by 30.05%. Results of scanning electron microscope demonstrated that ultrasound increased surface area and loosened structures of immobilized enzymes. Higher Vmaxand lower Kmwere obtained after ultrasound treatment, indicating the increased catalytic efficiency and enhanced affinity of immobilized pectinase. Furthermore, the optimum temperature and pH for free and immobilized pectinase remained unchanged at 50°C and pH 4. Thermostability, reaction stability and reusability of two ultrasound-treated pectinase enzymes slightly decreased due to structural matrix changes.
authors.affiliation: College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China.
authors.forename: Xiaobin
authors.initials: X
authors.lastname: Ma
authors.affiliation: College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China.
authors.forename: Danli
authors.initials: D
authors.lastname: Wang
authors.affiliation: Department of Food Science, University of Illinois at Urbana-Chanpaign, Urbana 61801, United States.
authors.forename: Michelle
authors.initials: M
authors.lastname: Yin
authors.affiliation: Department of Food Science, University of Illinois at Urbana-Chanpaign, Urbana 61801, United States.
authors.forename: Juliet
authors.initials: J
authors.lastname: Lucente
authors.affiliation: College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China.
authors.forename: Wenjun
authors.initials: W
authors.lastname: Wang
authors.affiliation: College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China; Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang R&D Center for Food Technology and Equipment, Hangzhou 310058, China.
authors.forename: Tian
authors.initials: T
authors.lastname: Ding
authors.affiliation: College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China; Fuli Institute of Food Science, Zhejiang University, Hangzhou 310058, China; Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang R&D Center for Food Technology and Equipment, Hangzhou 310058, China.
authors.forename: Xingqian
authors.initials: X
authors.lastname: Ye
authors.affiliation: College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China; Fuli Institute of Food Science, Zhejiang University, Hangzhou 310058, China; Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang R&D Center for Food Technology and Equipment, Hangzhou 310058, China. Electronic address: dhliu@zju.edu.cn.
authors.forename: Donghong
authors.initials: D
authors.lastname: Liu
mesh_terms: D000464:Alginates / Q000737:chemistry; D001234:Aspergillus niger / Q000201:enzymology; D002122:Calcium Chloride / Q000737:chemistry; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000737:chemistry* / Q000378:metabolism*; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007221:Industry; D011096:Polygalacturonase / Q000737:chemistry* / Q000378:metabolism*; D013696:Temperature; D000069453:Ultrasonic Waves
chemical_list: D000464:Alginates; D004800:Enzymes, Immobilized; D006603:Hexuronic Acids; D020723:Glucuronic Acid; D011096:Polygalacturonase; D002122:Calcium Chloride
keywords: Catalytic activity; Enzymatic kinetics; Immobilization yield; Stability; Structure