Combination of wet disk milling and hydrogen peroxide treatments for enhancing saccharification of sugarcane bagasse

A pretreatment method using wet disk milling (WDM) and hydrogen peroxide (HP) was investigated to produce a saccharified solution with a high glucose concentration from sugarcane bagasse. The chemical composition of the bagasse was uninfluenced by WDM treatment alone, whereas a slight reduction in the contents of lignin and xylan was effected by HP treatment alone performed at neutral pH. The combination of WDM treatment and HP treatment (WDM–HP treatment) significantly increased the removal of lignin and xylan. A cellulose-rich material containing 87% glucan was obtained by performing the HP treatment at 70 °C using 2.5% biomass, after WDM treatment. By using 15% WDM, HP- and WDM–HP-treated bagasse, glucose concentrations of 28 g/L, 27 g/L, and 98 g/L, respectively, were obtained from the various saccharification processes, suggesting the feasibility of the WDM–HP treatment for the production of a saccharified solution with high glucose concentration. Moreover, WDM–HP-treated bagasse was shown to be a good substitute for cellulose in cellulase production by Acremonium cellulolyticus. Under the same conditions, the treated bagasse provided a cellulase activity of 8.2 FPU/mL compared with the value of 7.9 FPU/mL provided by the commercial cellulose, SF 40.

► Wet disk milling and hydrogen peroxide treatments of bagasse were investigated.
► HP followed by WDM (WDM–HP) treatment produced high bagasse delignification.
► WDM–HP treatment significantly increased glucose concentration in saccharification.
► WDM–HP-treated bagasse is a good substitute for cellulose in cellulase production.