Browsing by Author "Basak, E"

Now showing 1 - 2 of 2
  • No Thumbnail Available
    Item
    Immobilization of catalase on chitosan and amino acid-modified chitosan beads
    Basak, E; Aydemir, T
    Bovine liver catalase was covalently immobilized onto amino acid-modified chitosan beads. The beads were characterized with SEM, FTIR, TGA and the effects of immobilization on optimum pH and temperature, thermostability, reusability were evaluated. Immobilized catalase showed the maximal enzyme activity at pH 7.0 at 30 degrees C. The kinetic parameters, K-m and V-max, for immobilized catalase on alanine-chitosan beads and lysine-chitosan beads were estimated to be 25.67 mM, 27 mM and 201.39 mu mol H2O2/min, 197.50 mu mol H2O2/min, respectively. The activity of the immobilized catalase on Ala-CB and Lys-CB retained 40% of its high initial activity after 100 times of reuse.
  • No Thumbnail Available
    Item
    Comperative study of catalase immobilization on chitosan, magnetic chitosan and chitosan-clay composite beads
    Basak, E; Aydemir, T; Dinçer, A; Becerik, SÇ
    Catalase was immobilized on chitosan and modified chitosan. Studies were carried out on free-immobilized catalase concerning the determination of optimum temperature, pH, thermal, storage stability, reusability, and kinetic parameters. Optimum temperature and pH for free catalase and catalase immobilized were found as 35 degrees C and 7.0, respectively. After 100 times of repeated tests, the immobilized catalases on chitosan-clay and magnetic chitosan maintain over 50% and 60% of the original activity, respectively. The ease of catalase immobilization on low-cost matrices and good stability upon immobilization in the present study make it a suitable product for further use in the food industry.