Optimized Conditions for Preparing a Heterogeneous Biocatalyst via Cross-Linked Enzyme Aggregates (CLEAs) of β-Glucosidase from Aspergillus niger

This study mainly aims to find the optimal conditions for immobilizing a non-commercial β-glucosidase from Aspergillus niger via cross-linked enzyme aggregates (CLEAs) by investigating effect of cross-linking agent (glutaraldehyde) concentration and soy protein isolate/enzyme ratio (or spacer/enzyme ratio) on catalytic performance through central composite rotatable design (CCRD). The influence certain parameters such as pH temperature hydrolytic activity resulting heterogeneous biocatalyst was assessed compared with those soluble enzyme. both immobilized hydrolyzing ρ-nitrophenyl-β-D-glucopyranoside (ρ-NPG) at 4.5 50 °C. It found that there maximum recovered around 33% (corresponding 0.48 U/mL) in 4.69 (mg/mg) using 25.5 mM glutaraldehyde. were 60 °C 4.5, respectively, while CLEAs between 65 3.5 4.0. These results reveal is more stable wider range than its form. Furthermore, an improvement observed thermal stability after immobilization. After 150 days 4 °C, retained 80% original activity, only 10%. preparation also characterized TG/DTG FT-IR analyses confirmed introduction carbon chains cross-linking. Therefore, prepared this has improved stabilization, it interesting approach preparing biocatalysts industrial applications.