2-28: Effect of pretreatment on cellulose DP reduction and the relationship between DP reduction and cellulose digestibility

    Understanding the chemical and physical factors governing biomass recalcitrance to enzymatic hydrolysis is critical to biomass conversion. The degree of polymerization(DP) of cellulose is considered to be one of the most important properties affecting the enzymatic hydrolysis of cellulose. However, there are few studies investigating the effect of pretreatment on cellulose DP and the relationship between cellulose DP and enzymatic hydrolysis. In this study, the DP of cellulose was determined by size exclusion chromatography after carbanilation of the cellulose. The digestibility of a series of pretreated celluloses differing in DP was tested with a purified CBH1 and a cellulase complex. The results show that the cellulose DP decreased with increasing pretreatment severity, and this resulted in an increase in the cellulose digestibility.  The effect of pretreatment parameters (time, temperature, acid concentration) on cellulose DP was investigated to determine which had the greatest influence on DP reduction.