Evaluation of structural factors affecting high solids enzymatic saccharification of alkali-pretreated sugarcane bagasse

摘要

Filter paper and xylan were selected as model substrates simulating cellulose and hemicellulose components. Enzymatic hydrolysis of different substrates: pure filter paper, xylan added system, alkali pretreated sugarcane bagasse (SCB) were studied at varying solids loading to assess the effect of hemicellulose on substrate conversion at high solids loading. Meanwhile, hydrophilic lignin (sulfonated lignin or alkali lignin) was added to 15% (w/v) alkali-pretreated SCB hydrolysis system to investigate lignin influence on cellulose digestibility. It was found that xylan as the physical barrier had inhibitory effect on cellulose hydrolysis. Enzymatic saccharification of alkali-pretreated SCB was significantly improved by supplementing with hydrophilic lignin. The effect of lignin on substrate conversion depended not only on the hydrophilic characteristics of lignin, but also on the form of lignin present in different substrates.