Immobilization, characteristics and applications of cellulase enzyme

Lignocellulosic biomass is a potential renewable resource in the production of monomeric sugars by hydrolysis of cellulosic enzymes. Cellulase enzyme consisting of endoglucanase, exoglucanase and β-glycosidase enzymes, cellulosic glycoside fragments with synergistic effects of these enzymes. These enzymes can be produced with a wide variety of microorganisms, especially fungi. In this study, cellulase from Trichoderma reesei ATCC 26921 was immobilized on chitosan and magnetic chitosan beads using two different crosslinking agents: glutaraldehyde and genipin. The physical, chemical and biochemical properties of immobilized cellulase and its use in lignocellulosic biomass saccharification have been extensively researched. The structure and morphology of the synthesized composite beads were characterized by SEM, TGA, FTIR and VSM analyzes. Optimum temperature and pH values of free and immobilized cellulase were 50 °C and 5.0, respectively. It was observed that the immobilized cellulase on genipin and glutaraldehyde activated composite beads showed higher tolerance to changes in pH and temperature. Also, the cellulase immobilized on composite beads showed better storage stability than free cellulase. Optimum concentration was found to be 0.6% (w / v) and 4% (v / v) for genipin and glutaraldehyde, respectively. The percent recovered enzyme activity was found to be 82% and 76% for the magnetic chitosan beads activated with genipin and glutaraldehyde, respectively. In the saccharification study to analyze the catalytic performance of immobilized enzymes, the activity of genipin and glutaraldehyde-activated beads after 5 uses was 78% and 74%, respectively, and carrier morphology was not changed. As a result of the calculations made after saccharification, the saccharification rate of corn leaves, artichoke leaves and pine bark was 92%, 79%, 68% respectively. The results obtained in this study support the use of genipin as an alternative eco-friendly alternative to glutaraldehyde, which is commonly used as crosslinker in enzyme immobilization, and demonstrate the utility of both immobilized enzymes in the saccharification process.