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Release and Recovery of Porcine Pepsin and Bovine Chymosin from Reverse Micelles: A New Technique Based on Isopropyl Alcohol Addition
Author(s) -
Carlson A.,
Nagarajan R.
Publication year - 1992
Publication title -
biotechnology progress
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.572
H-Index - 129
eISSN - 1520-6033
pISSN - 8756-7938
DOI - 10.1021/bp00013a013
Subject(s) - chymosin , isoelectric point , chemistry , pepsin , chromatography , micelle , isopropyl alcohol , aqueous solution , aqueous two phase system , biochemistry , enzyme , organic chemistry
After complete solubilization by the direct method, porcine pepsin was not released from AOT in isooctane reverse micelles even under aqueous‐phase conditions which would not ordinarily allow uptake. Similarly, bovine chymosin, once forward‐transferred at a pH below its isoelectric point, was not back‐transferred into an aqueous contact phase buffered at a pH value above its isoelectric point. These results show that there is significant hysteresis in the forward‐and backward‐transfer processes and further imply that kinetics, and not equilibrium, control uptake or release processes for these enzymes. The addition of 10–15 % isopropyl alcohol to the aqueous phase increases the rate of protein release dramatically and allows for nearly complete back‐transfer of porcine pepsin and 70% back‐transfer of bovine chymosin. IPA addition does not destroy the functional integrity of the system since forward transfer of bovine chymosin still occurs at pH values below (but not above) the p I of the protein.