Enzymatic hydrolysis of biomass with recyclable use of cellobiase enzyme immobilized in sol–gel routed mesoporous silica

In this study, biomass was enzymatically hydrolyzed using a new immobilized cellobiase system to produce cellulosic ethanol. The use of immobilized cellobiase allows the enzyme to be easily separated from the reaction mixture by hydrolysis. Cellobiase is immobilized on a porous solid silica host material by an acid-catalyzed non-surfactant template sol-gel reaction of tetraethyl orthosilicate (TEOS). The pore size and porosity of the host material are controlled by varying the template (d-fructose) content. Compared to hydrolysis by free cellobiase, using the immobilized cellobiase sample, pretreated biomass with hydrolysis efficiency of up to 74% (using FeCl 3 pretreated biomass) and 81% (using oxalic acid pretreatment) Was hydrolyzed. Processing biomass). After the hydrolysis reaction, the solid immobilized enzyme sample can be easily recycled from the reaction mixture. When multiple batches are recycled, immobilized samples retain their enzymatic activity in biomass hydrolysis. Reusable immobilized cellobiase with retention activity will actively reduce enzyme costs. Therefore, our immobilized cellobiase has opened up great potential to enzymatically hydrolyze biomass to produce cellulosic ethanol. Because it reduces the overall process cost.

► Immobilized cellobiase. It is used to hydrolyze biomass (cellulose) for production of cellulosic ethanol. ► The hydrolysis efficiency of immobilized cellobiase is 81% as compared with free cellobiase. ► The immobilized cellobiase can recover the enzyme and reuse it

Cellulosic materials are the most abundant renewable carbon source in the world. Cellulose can be hydrolyzed using cellulase to produce glucose and glucose can be used to produce ethanol, organic acids and other chemicals. Cellulases are complex enzymes including endoglucanase (EC 3.2.1.4), exoglucanase (EC 3.2.1.91) and cellobiase (EC 3.2.1.21). Hydrolysis of natural cellulose to glucose depends on the synergistic effect of these three components. Trichoderma reese produces the highest cellulase activity and has high endoglucanase and exoglucanase activity, but relatively low cellobiase activity. Therefore, increasing the activity of cellobiase in the cellulase reaction system is the key to increasing the glycation yield of cellulose resources. Aspergillus niger LORRE 012 is a high yield strain for producing cellobiase. The spores of this strain were found to be rich in cellobiase.

In this study, biomass was enzymatically hydrolyzed using a new immobilized cellobiase system to produce cellulosic ethanol. The use of immobilized cellobiase allows the enzyme to be easily separated from the reaction mixture by hydrolysis. Cellobiase is immobilized on a porous solid silica host material by an acid-catalyzed non-surfactant template sol-gel reaction of tetraethyl orthosilicate (TEOS). The pore size and porosity of the host material are controlled by varying the template (d-fructose) content. Compared to hydrolysis by free cellobiase, using the immobilized cellobiase sample, pretreated biomass with hydrolysis efficiency of up to 74% (using FeCl 3 pretreated biomass) and 81% (using oxalic acid pretreatment) Was hydrolyzed. Processing biomass). After the hydrolysis reaction, the solid immobilized enzyme sample can be easily recycled from the reaction mixture.

Enzymatic hydrolysis of biomass can be recycled to cellobiase immobilized on pore mesoporous silica in sol - gel