PREPARATION AND CHARACTERIZATION OF CROSS-LINKED ENZYME AGGREGATES (CLEAs) OF AEROMONAS CAVIAE AU04 PROTEASE

Abstract

Protease from Aeromonas caviae AU04 was immobilized as cross-linked enzymes aggregates (CLEAs) with salt precipitation and glutaraldehyde as cross-linker. (NH4)2SO4 was the most suitable precipitant with 90% of the activity recovery. Immobilization was carried out for 8 h with agitation at 30˚C and pH 8.0.Maximum cross-linking was obtained at 70 mM glutaraldehyde and 6 h of cross-linking time at 30˚C. It was able to retained activity after 24 h in the presence of non-polar solvents at 30˚C. The CLEAs was reused for 10 cycles retaining about 42% of the activity. It showed enhanced storage stability at 4˚C when compared to the native form. SEM image of the freshly prepared CLEAs showed a coarse-grained appearance and more structured. It was able to degrade the native chicken feather after 35 h of incubation. These results suggest a potential CLEAs application for various industries.