Purification of crude cellulase obtained from Aspergillus foetidus and its immobilization in agar xerogel: A comparative study with commercial cellulase immobilized in similar support

Abstract

This research study is a comparative study of the characteristics of partially purified cellulase produced from Aspergillus foetidus through solid‐state fermentation, in its free form, and adsorbed onto agar xerogel, against free and similarly immobilized commercial cellulase, and the determination of their efficacy for clarifying carrot juice. The purification process resulted in a 5.64‐fold enhancement in activity, and the partially purified cellulase was successfully immobilized via adsorption. The partially purified cellulase immobilized on agar xerogel demonstrated 88.05% binding efficiency with 0.71 IU/g activity, while commercial cellulase immobilized on agar xerogel showed 89.97% binding efficiency and 1.14 IU/g activity under similar conditions. The characterization results showed identical optimum temperatures for free partially purified cellulase, agar xerogel‐adsorbed partially purified cellulase, and agar xerogel‐adsorbed commercial cellulase, but a lower optimum temperature for free commercial cellulase. In contrast, the optimum pH for agar xerogel‐adsorbed commercial cellulase was higher compared to the other forms of cellulase. The reusability test revealed satisfactory performance, with both enzymes maintaining over 40% residual activity after five cycles, and the partially purified form showing greater resistance to degradation. When applied to carrot juice extraction, all juices treated with cellulase showed higher yields and improved properties compared to the untreated juice.