Partitioning and purification of extracellular β-1,3-1,4-glucanase in aqueous two-phase systems

• Published in: Journal of Zhejiang University. B. Science Vol. 6; no. 8; pp. 825 - 831
• Main Author: 何国庆 张秀艳 汤兴俊 陈启和 阮辉
• Format: Journal Article
• Language: English
• Published: China School of Biosystem Engineering and Food Science, Zhejiang University, Hangzhou 310029, China 01.08.2005; Zhejiang University Press
• Subjects: Bacillus subtilis; Bacillus subtilis - enzymology; Chemical Fractionation - methods; Endo-1,3-beta-Glucanase - biosynthesis; Endo-1,3-beta-Glucanase - chemistry; Endo-1,3-beta-Glucanase - isolation & purification; Extracellular Fluid - chemistry; Phase Transition; Plant & Animal Sciences and Biotechnology; Water - chemistry; 净化系统; 水生二相系统; 葡聚糖酶; 酶分离; Aqueous two-phase system,Partition,β-1,3-1,4-glucanase
• ISSN: 1673-1581; 1862-1783
• DOI: 10.1631/jzus.2005.B0825

The partition behaviors of β-1,3-1,4-glucanase, α-amylase and neutral proteases from clarified and whole fermentation broths of Bacillus subtilis ZJF-1A5 were investigated. An aqueous two-phase system （polyethylene glycol （PEG）/MgSO4） was examined with regard to the effects of PEG molecular weight （MW） and concentration, MgSO4 concentration, pH and NaC1 concentration on enzyme partition and extraction. The MW and concentration of PEG were found to have significant effects on enzyme partition and extraction with low MW PEG showing the greatest benefit in the partition and extraction of β-glucanase with the PEG/MgSO4 system. MgSO4 concentration influenced the partition and extraction of β-glucanase significantly, pH had little effect on β-glucanase or proteases partition but affected a-amylase partition when pH was over 7.0. The addition of NaCl had little effect on the partition behavior of β-glucanase but had very significant effects on the partitioning of α-amylase and on the neutral proteases. The partition behaviors of β-glucanase, α-amylase and proteases in whole broth were also investigated and results were similar to those obtained with clarified fermentation broth. A two-step process for purifying β-glucanase was developed, which achieved β-glucanase recovery of 65.3% and specific activity of 14027 U/mg, 6.6 times improvement over the whole broth.