Conditions for immobilization of cyclodextrin glucanotransferase from <i>Bacillus megaterium</i> on DEAE-cellulose activated with glutaraldehyde

The aim of the research is investigation on the conditions for immobilization of cyclodextrin glucanotransferase (CGTase) produced by Bacillus megaterium on DEAE-cellulose activated with glutaraldehyde. The used support was chosen as the most suitable one, after testing different supports. Several factors that influence the immobilization process on DEAE-cellulose activated with glutaraldehyde were studied, including enzyme amount, pH, glutaraldehyde concentration and time of immobilization. All tested factors significantly affected the immobilization process of CGTase and the corresponding activity parameters of immobilized biocatalyst. The immobilization process of the enzyme was evaluated by calculating the immobilization yield, immobilization efficiency and activity recovery of CGTase. As a result of the performed studies the optimal conditions for CGTase immobilization on DEAE-cellulose were determined. They were as follows: CGTase enzyme amount 8 U, pH value during immobilization 7.0, 2 % (v/v) concentration of glutaraldehyde, immobilization time of 3 h. At these conditions immobilization yield was 71.87 %, immobilization efficiency was 10.49 %, and activity recovery was 7.54 %, which were significantly improved indicators for enzyme immobilization in comparison to the initial values before the optimization of the immobilization conditions.