Premium
Preparation of crosslinked enzyme aggregates (CLEAs) of acid urease with urethanase activity and their application
Author(s) -
Zhang Qian,
Zha Xiaohong,
Zhou Nandi,
Tian Yaping
Publication year - 2016
Publication title -
journal of basic microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.58
H-Index - 54
eISSN - 1521-4028
pISSN - 0233-111X
DOI - 10.1002/jobm.201500498
Subject(s) - chemistry , urease , urea , chromatography , wine , bovine serum albumin , nuclear chemistry , biochemistry , food science
An acid urease from Providencia rettgeri JN‐B815 was purified via ultrasonication, ethanol precipitation, and DEAE ion‐exchange column chromatography. It was found that the enzyme exhibits not only urease activity, but also urethanase activity, which made it possible to reduce EC already existed or would produce and its precursor urea at the same time. Then, crosslinked enzyme aggregates of P. rettgeri urease (PRU‐CLEAs) were prepared using genipin as crosslinking agent. The purification process of acid urease, the effects of genipin concentration, and crosslinking time on PRU‐CLEAs activity were investigated. The crosslinking was performed at pH 4.5 for 2.5 h, using 0.3% genipin as crosslinking agent, and 0.3 g · L −1 bovine serum albumin as protein feeder. Using the obtained PRU‐CLEAs, the removal rate of urea was up to 9.31 mg · L −1 · h −1 . The removal rate of urea was still up to 7.56 mg · L −1 · h −1 after PRU‐CLEAs was re‐used for 6 times. When PRU‐CLEAs were applied in a batch stirred and membrane reactor, the removal rate of urea in rice wine reached 5.16 mg · L −1 · h −1 and the removal rate of EC was 9.21 μg · L −1 · h −1 . Furthermore, the treatment with PRU‐CLEAs revealed no significant change of volatile flavor substances in Chinese rice wine. Thus PRU‐CLEAs have great potential in the elimination of EC in Chinese rice wine.