Structural changes in sugarcane bagasse cellulose caused by enzymatic hydrolysis

• Main Authors: Makiko Imai, Yoshiki Horikawa, Shingo Kiyoto, Tomoya Imai, Junji Sugiyama
• Format: Article
• Language: English
• Published: SpringerOpen 2020-02-01
• Series: Journal of Wood Science
• Subjects: Cellulose; Cellulase; Deuteration; Hydrophobic plane; Hydrophilic plane; SAXS
• Online Access: https://doi.org/10.1186/s10086-020-01859-2

Abstract Cellulose I is not completely saccharified to glucose at a low cellulase concentration. In this study, sugarcane cellulose saccharification residues were investigated. Transmission electron microscopy images indicated that the cellulose microfibrils became shorter in the early stages of saccharification and gradually became narrower. The degree of polymerization also decreased in the early stages of saccharification. Cellulose saccharification residues were deuterated by immersing them in deuterium oxide. Infra-red spectra of the deuterated residues indicated that the deuterated hydroxyl group ratio decreased as saccharification progressed. This indicated that cellulose microfibrils were hydrolyzed in their hydrophobic planes by cellulase as if the surfaces were scraped. The increase of hydrophobic planes caused microfibril aggregation, poor accessibility of cellulase to the microfibrils, and a low saccharification rate.