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HERO ID
2849828
Reference Type
Journal Article
Title
Three phase partitioning of zingibain, a milk-clotting enzyme from Zingiber officinale Roscoe rhizomes
Author(s)
Gagaoua, M; Hoggas, N; Hafid, K
Year
2015
Is Peer Reviewed?
Yes
Journal
International Journal of Biological Macromolecules
ISSN:
0141-8130
EISSN:
1879-0003
Volume
73
Page Numbers
245-252
Language
English
PMID
25475843
DOI
10.1016/j.ijbiomac.2014.10.069
Web of Science Id
WOS:000349194300032
Abstract
The present work describes for the first time an elegant non-chromatographic method, the three phase partitioning for the purification and recovery of zingibain, a milk-clotting enzyme, from Zingiber officinale rhizomes. Factors affecting partitioning efficiency such as (NH4)2SO4 saturation, crude extract to t-butanol ratio and pH on zingibain partitioning were investigated. Optimal purification parameters were 50% (NH4)2SO4 saturation with 1.0:1.0 ratio of crude extract:t-butanol at pH 7.0, which gave 14.91 purification fold with 215% recovery of zingibain. The enzyme was found to be exclusively partitioned in the aqueous phase. The enzyme showed a prominent single band on SDS-PAGE. It is a monomeric protein of 33.8 kDa and its isoelectric point is 4.38. The enzyme exhibited maximal proteolytic activity at a temperature of 60 °C and pH 7.0. It was found to be stable at 40-65 °C during 2 h. The enzyme was found to be highly stable against numerous metal ions and its activity was enhanced by Ca(2+), K(+) and Na(+). It was completely inhibited by heavy metal ions such as Cu(2+) and Hg(2+) and partially by Cd(+). Zingibain milk-clotting activity (MCA) was found to be highly stable when stored under freezing (-20 °C) for 30 days compared at 4 °C.
Keywords
Milk-clotting; Purification; Recovery; Three phase partitioning (TPP); Zingibain; Zingiber officinale Roscoe
Tags
IRIS
•
tert-Butanol
Considered Studies
Electronic Search
Excluded/ Not on Topic
Methodology/Solvent
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