Jump to Main Content
Sugar loss and enzyme inhibition due to oligosaccharide accumulation during high solids-loading enzymatic hydrolysis
- Saisi Xue, Nirmal Uppugundla, Michael J. Bowman, David Cavalier, Leonardo da Costa Sousa, Bruce E. Dale, Venkatesh Balan
- Biotechnology for biofuels 2015 v.8 no.195 pp. -
- ammonia, charcoal, corn stover, enzymatic hydrolysis, enzyme inhibition, fractionation, gel chromatography, hydrolysates, ionic liquids, oligosaccharides, polygalacturonase, polymerization, xylan
- Oligosaccharide accumulation occurs during high solid loading enzymatic hydrolysis of corn stover (CS) irrespective of using different pretreated corn stover (dilute acid: DA, ionic liquids: IL, ammonia fiber expansion: AFEX and extractive ammonia: EA). The methodology for large-scale separation of recalcitrant oligosaccharides from 25% solids-loading AFEX-corn stover hydrolysate (ACH) using charcoal fractionation and size exclusion chromatography is reported here for the first time. Oligosaccharides with higher degree of polymerization (DP) are recalcitrant towards commercial enzyme mixtures (Ctec2, Htec2 and Multifect pectinase (MP)) compared to lower DP oligosaccharides. Enzyme inhibition studies using isolated substrates (Avicel and xylan) show that low DP oligosaccharides also inhibit commercial enzymes. Addition of monomeric sugars to oligosaccharides increases the inhibitory effects of oligosaccharides on commercial enzymes.