(490e) Lignosulfonate on Enzymatic Saccharification of Cellulsoe

The effects of lignosulfonate (LS) on enzymatic saccharification of pure cellulose and different pretretaed lignocellulses were studied.  Four fractions of LS with different molecular weight (MW) prepared by ultrafiltration of a commercial LS were applied at different loadings to enzymatic hydrolysis of Whatman paper under different pH.  Using LS fractions with low MW and high degree of sulfonation can enhance enzymatic cellulose saccharification despite LS can bind to cellulase nonproductively.  The enhancing effect varies with LS properties, its loading, and hydrolysis pH.  Inhibitive effect on cellulose saccharification was also observed using LS with large MW and low degree of sulfonation.  The concept of “LS-cellulase aggregate stabilized and enhanced cellulase binding” was proposed to explain the observed enhancement of cellulose saccharification.  The concept was demonstrated by the linear correlation between the measured amount of bound cellulase and saccharification efficiency with and without LS of different MW in a range of pH.  When lignosulfonate was applied to differently lignocellulses, the enhancememnt of cellulose saccharification depends on not only the lignosulfonate molecular weight of degree of sulfonation, but alos depends on the lignin properties on the substrate.