Alginate-mediated immobilization of jackfruit (Artocarpus heterophyllus) latex serine protease enzyme exhibits improved catalytic properties

Serine proteases have been receiving special attention from the industrial point of view, due to their thermo-stable properties and activity over wide ranges of pH. In the present investigation, a serine protease (49.3 kDa) from jackfruit latex has been purified using chromatographic techniques. Fold purification of the serine protease in the final purification step was 92.41 with 24% yield. The protease is completely inhibited by PMSF, a serine protease-specific inhibitor at a minimal concentration (100 µM). The purified serine protease was immobilized with sodium alginate (2.5%) and calcium chloride (0.3 M) solution. The kinetic studies of immobilized enzyme showed stable activity up to pH 7, and can withstand temperatures up to 45 °C. The immobilization process improves the catalytic efficiency of the enzyme over purified soluble enzyme (for K_cat 1.4 times and for K_cat/K_m 1.21 times). Our results depicted that alginate mediated immobilization of serine protease greatly improves the pH and temperature optima which broadens the scope of usage of the enzyme further.