Downstream processing of soy hull peroxidase employing reverse micellar extraction

Abstract

Phase transfer studies were conducted to evaluate the solubilization of soy hull peroxidase (SHP) in reverse micelles formed in isooctane/butanol/hexanol using the cationic surfactant cetyltrimethylammonium bromide (CTAB). The effect of various parameters such as pH, ionic strength, surfactant concentration of the initial aqueous phase for forward extraction and buffer pH, type and concentration of salt, concentration of isopropyl alcohol and volume ratio for back extraction was studied to improve the efficiency of reverse micellar extraction. The active SHP was recovered after a complete cycle of forward and back extraction. A forward extraction efficiency of 100%, back extraction efficiency of 36%, overall activity recovery of 90% and purification fold of 4.72 were obtained under optimised conditions. Anionic surfactant sodium bis (2-ethylhexyl) sulfosuccinate (AOT) did not yield good results under the conditions studied. The phase transfer of soy hull peroxidase was found to be controlled by electrostatic and hydrophobic interactions during forward and back extraction respectively.