Optimization of Immobilization Condition of Protease Extracted from Silver Catfish (Pangasius Sutchi) Viscera in Calcium Alginate by using Response Surface Methodology (RSM)

Abstract

The term of immobilized enzymes refers to enzymes that physically entrapped within pores of synthetic or natural polymeric network with no alteration in the enzyme catalytic activities. In this study, protease from silver catfish viscera have been extracted, partially purified by acetone precipitation method and immobilised in the calcium alginate beads. Various range of sodium alginate (1–5% w/v) and calcium chloride (0.1–0.5 M) concentrations were used for the optimization purpose. Proteolytic activity of the protease in the alginate beads was measured as a response to the independent variables by using casein as a substrate. The highest actual and predicted proteolytic activities were at run 12 with 674.77 CDU/mg and 639.26 CDU/mg, respectively, under predetermined factors, in which the sodium alginate and calcium chloride solution concentrations were at 3.00% (w/v) and 0.30 M, respectively. The lowest actual and predicted proteolytic activities were at run 2 with the values of 77.35 CDU/mg and 71.53 CDU/mg, respectively, whereby factors include were a sodium alginate of 4.00% (w/v) and 0.20 M of calcium chloride solution. For the experimental feasibilities, the optimum conditions that was feasible to be carried out was with a sodium alginate of 2.99% (w/v) and 0.30 M calcium chloride solution. Verification for the optimum condition was performed and there was no significant difference (p > 0.05) between the predicted (638.19 CDU/mg) and verified (699.82 CDU/mg) values. Thus, indicating that the model was significant and can be used to produce the immobilize protease under the optimum condition.