Enzymatic hydrolysis, inhibition and characterization of sugarcane bagasse pretreated at different severities

Pretreatment of sugarcane bagasse was performed in a two steps thermochemical treatment, with a steam explosion in the last step. The raw and pretreated solids were also submitted to evaluate the changes to the chemical structures, to thermic stability and to the crystallinity. In all cases, pretreatment of sugarcane bagasse increased the crystallinity index and crystallite width of the substrates. It also modified the thermal stability of the substrates, making them more thermally stable when compared to raw bagasse. Some of the liquors obtained after first step pretreatment, which had different concentration of monomers, oligomers and degradation compounds, were evaluated. The inhibition profile of these liquors has shown that oligomers were the most important factor of inhibition, followed by the monomers glucose and xylose. Pretreatment in two steps is an interesting alternative to pretreated sugarcane bagasse, although there is still room for optimization of the process.