Effect Of Cellulose And Lignin On Xylanase Hydrolysis

Lignocellulosic materials is the most potential and renewable resources for the production of biofuels.Enzymatic saccharification efficiency of lignocellulosic materials was low.It needs to add other enzymes improve the enzymatic hydrolysis efficiency in the enzymatic hydrolysis system.However,lignin,cellulose derivates and phenolic compounds of the hydrolysates were all found to have a negative effect on xylanase hydrolysis.In order to explore the influence factor of xylanase hydrolysis,effects of cellulose,cellulose,glucose and lignin on xylanase hydrolysis were studied,and inhibition mechanism of cellulose,cellobiose,glucose and lignin on xylanase was investigated by the kinetics and adsorption experiment of xylanase.(1)In this work,the results indicated that cellulose,cellobiose,and glucose were all found to have negative effects on the hydrolytic action of endo-xylanase,not on that ofβ-xylosidase.After addition of cellulose(50 mg/m L),cellobiose(50 mg/m L),and glucose(50 mg/m L),the degrees of inhibition of cellulose,cellobiose and glucose on the hydrolysis of insoluble xylan by xylanase were 10.4%,19.7%,and 17.7%,respectively.Among these inhibitors,cellobiose exhibited the strongest inhibitory effect on xylanase,followed by glucose and cellulose.(2)Considerable amount of xylanase showed a tendency to adsorb on Avice.During the hydrolysis of biomass,cellulose and xylan may competitively interact with xylanase,thus reducing the accessibility of xylanase to xylan,and therefore lowering the hydrolytic efficiency of the xylanase.Kinetic analysis revealed that both cellobiose and glucose competitively inhibited the activity of endo-xylanase.(3)After addition of acid insoluble lignin(10 mg/m L)and enzymatic hydrolysis lignin(10 mg/m L),the hydrolysis yield of xylan decreased from 72.8% to 56.7% and 60.5%.The results showed that acid insoluble lignin and enzymatic hydrolysis lignin had the inhibitory effect on endo-xylanase and β-xylosidase.Acid insoluble lignin exhibited the strongest inhibitory effect on xylanase.The hydrophobicity of acid insoluble lignin was higher than that of enzymatic hydrolysis lignin.Nonproductive adsorption of xylanase onto lignin decreased the xylanase activity and hydrolysis yield of xylan by xylanase.Effect factors and mechanism of xylanase hydrolysis efficiency were indicated from optimized the composition of the enzymes.The conclusions of this work would provide a theoretical basis for promoting the hydrolysis efficiency of xylanase and offer a basic information for the efficient conversion of xylan-containing biomass.