Relationship between physicochemical properties and enzymatic hydrolysis of sugarcane bagasse varieties for bioethanol production

•Classical and breeding sugarcane bagasse varieties were evaluated.•Two enzyme loading was applied to evaluate the digestibility of materials.•Varieties were compared based on internal and external specific surface.•Enzymatic hydrolysis in two levels identified best varieties as raw materials.•Physicochemical properties identified varieties with a better potential for ethanol.•Internal and external surface area direct correlated to enzymatic hydrolysis yield.

The structural and physicochemical characteristics are associated with resistance of plant cell walls to saccharification by enzymes. The effect of physicochemical properties on glucose yield of bagasse from different varieties of sugarcane at low and high enzyme dosages was investigated. The result showed that glucose yield at low enzyme dosage was positively linear correlated with the yield at high enzyme dosage, for both the untreated and pretreated materials. The pretreatment significantly increased the accessibility of substrates by enzyme due to the increase of internal and external surface area. Glucose yield also showed a linear correlation with dye adsorption. However, the increase in glucose yield as a result of pretreatment did not correlate with the increases in crystallinity index and decreases in degree of polymerization. The Principal Component Analysis of infrared data indicated that lignin was the main component that differentiated the varieties before and after pretreatment. These results suggested that the key differences in pretreatment responses among varieties could be mainly attributed to their differences in the internal and external surface area after pretreatment.