Evaluation of bagasse from different varieties of sugarcane by dilute acid pretreatment and enzymatic hydrolysis

- We evaluated bagasse from 115 varieties of sugarcane by pretreatment-hydrolysis.
- The fiber composition variability between varieties was statistically significant.
- The xylose yield was not affected by fiber composition or breeding technology.
- The glucose yield was strong correlated to all fiber components except extractives.
- Digestibility of many classical breeding varieties was affected by variety type.

Lignocellulosic ethanol is a promising alternative to gasoline that can be produced by fermentation of sugars present in lignocellulosic biomass. Improved properties of energy crops and reduction of lignocellulose recalcitrance to biological conversion have the potential to reduce production costs. This study evaluated bagasse from 115 varieties of sugarcane for fermentable sugar yield. The purpose was to select the preferred varieties with fiber of high processability without compromising juice ethanol and cane yield. Dilute acid pretreatment was employed to improve the sugars yield from the bagasse. The results showed wide variations in structural carbohydrates (as monosaccharide) content (66.6-77.6% dry matter (DM)) and lignin content (14.4-23.1% DM) between varieties. Combined sugar yield obtained after pretreatment and enzymatic hydrolysis also varied significantly (27.3-55.2 g/100 g DM). Further, it was demonstrated that some of the varieties had combined characteristics of high cane productivity and combined sugar yield after pretreatment-hydrolysis of the bagasse. These results suggest the incorporation of selection of varieties, given its contribution for developing a cost-efficient pretreatment and saccharification process.