Characteristics of pectinase treated with ultrasound both during and after the immobilization process

Xiaobin Ma; Danli Wang; Michelle Yin; Juliet Lucente; Wenjun Wang; Tian Ding; Xingqian Ye; Donghong Liu

doi:10.1016/j.ultsonch.2016.10.026

Characteristics of pectinase treated with ultrasound both during and after the immobilization process

Ultrason Sonochem. 2017 May:36:1-10. doi: 10.1016/j.ultsonch.2016.10.026. Epub 2016 Oct 29.

Authors

Xiaobin Ma¹, Danli Wang¹, Michelle Yin², Juliet Lucente², Wenjun Wang¹, Tian Ding³, Xingqian Ye⁴, Donghong Liu⁵

Affiliations

¹ College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China.
² Department of Food Science, University of Illinois at Urbana-Chanpaign, Urbana 61801, United States.
³ 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.
⁴ 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.
⁵ 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.

PMID: 28069187
DOI: 10.1016/j.ultsonch.2016.10.026

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^-1 for 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^-1 for 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 V_max and lower K_m were 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.

Keywords: Catalytic activity; Enzymatic kinetics; Immobilization yield; Stability; Structure.

MeSH terms

Alginates / chemistry
Aspergillus niger / enzymology
Calcium Chloride / chemistry
Enzyme Stability
Enzymes, Immobilized / chemistry*
Enzymes, Immobilized / metabolism*
Glucuronic Acid / chemistry
Hexuronic Acids / chemistry
Hydrogen-Ion Concentration
Industry
Polygalacturonase / chemistry*
Polygalacturonase / metabolism*
Temperature
Ultrasonic Waves*

Substances

Alginates
Enzymes, Immobilized
Hexuronic Acids
Glucuronic Acid
Polygalacturonase
Calcium Chloride