JOURNAL OF FOOD BIOCHEMISTRY, cilt.45, sa.4, 2021 (SCI-Expanded)
UV-cured epoxy-based polymeric film was prepared from glycidyl methacrylate, trimethylolpropane triacrylate, and poly(ethylene glycol) methylether acrylate. 2-hydroxy-2- methylpropiophenone was used as photo initiator. Covalent binding through epoxy groups was employed to immobilize beta-galactosidase from Escherichia coli onto this film, and immobilization conditions were optimized by the response surface methodology. ATR-Fourier transform infrared (FTIR) and scanning electron microscopy (SEM) analysis was carried out to characterize the epoxy-based polymeric film. Immobilization yield of beta-galactosidase on the material was calculated as 3.57 mg/g and the highest enzyme activity for the immobilized enzyme recorded at pH 6.5 degrees C and 60 degrees C. The immobilized enzyme preserved 51% of its activity at the end of 12 runs. Free and immobilized enzyme hydrolyzed 163.8 and 172.3 mu M lactose from 1% lactose, respectively. Kinetic parameters of both free and immobilized beta-galactosidase were also investigated, and K-m values were determined to be 0.647 and 0.7263 mM, respectively.