Glutaraldehyde-copper gelled chitosan beads: Characterization and utilization as covalent immobilizers

The robust chitosan (CHS)-Cu2+ interactions were utilized to prepare CHS beads. Glutaraldehyde (GA) was also added to the gelling medium to provide the functional entities needed for & beta;-ngalactosidase (& beta;G) covalent immobilization. The preparation of the GA-Cu-CHS beads was honed with respect to the concentrations of the utilized CuSO4, CHS, and GA solutions. A CHS concentration of 2% was favored. The optimal gelling medium comprised 0.2% CuSO4-1.12% GA. The beads were characterized via SEM and EDX. The beads enhanced mechanical traits were verified. The GA-Cu-CHS beads immobilized & beta;G, and the immobilization efficiency reached 47.67% when 2.56 Ug-1 & beta;G loading activity was adopted. The immobilized & beta;G (i & beta;G) experienced an acidic shift in its optimal pH range from 4.4 to 5.5 to 3.6-4.4. Moreover, its optimal temperature was slightly shifted following immobilization from 55-60 & DEG;C-60 & DEG;C. The Km and Vmax values of & beta;G were reduced from 84.4 mM to 19.0 & mu;mol/min mg enzyme to 64.9 mM and 5.6 & mu;mol/min mg enzyme following immobilization. The operational stability of i & beta;G was also studied while performing the 15 min lactose hydrolytic reaction at 37 & DEG;C, and 81.79% activity was obtained throughout the 15th hydrolytic cycle. Moreover, the i & beta;G provided 97.30% activity after 77 days of storage in distilled water in the fridge. Finally, the i & beta;G was utilized to degrade lactose in cheese whey and also in buffered lactose solution (BLS) at 45 & DEG;C and at pH 4.4. Each degradation cycle lasted 24 h and 78.52% of the inceptive released glucose was released during the BLS 5th degradation cycle.