Polyacrylamide beads: Polymer entrapment increases the catalytic efficiency and thermal stability of protease

Immobilization is a unique method for the improvement of product yield. During solid phase catalysis, the chemistry of the synthetic matrix plays an essential role in the performance of the biocatalyst. In the current study, immobilized protease within polyacrylamide macrosphere beads exhibited 76.0% entrapment yield with a remarkable stability of enzyme (33.0%) after 30 days of storage period at 4 degrees C. The entrapment of free enzyme within polyacrylamide also increased the optimal reaction temperature by 55 degrees C and provided a broad range of pH optima. Moreover, a significant enhancement in thermal stability was also detected. Polyacrylamide entrapped protease revealed up to 30.93% activity after incubation period of 30.0 min at 70 degrees C whereas, the free enzyme was completely inactivated at this temperature. Additionally, entrapped protease displayed an efficient recycling capacity and retained approximately 24.0% of its initial activity after eight successive reaction cycles. After entrapment of protease, the anchoring of substrate to the active site of the free protease exhibited change in K-m and V-max values. Therefore, owing to economic feasibility, the polyacrylamide entrapped protease might be a promising candidate for various applications in different industrial sectors. (C) 2017 Elsevier B.V. All rights reserved.