Carbohydrate composition of eucalyptus, bagasse and bamboo by a combination of methods

The carbohydrate composition of lignocellulosic biomass is normally obtained by the quantification of monomers after two stages of hydrolysis in H2SO4. A new two-stage hydrolysis protocol has recently been developed but so far only results for temperate hardwoods have been reported. In this investigation the new protocol was used in the analysis of depithed sugarcane bagasse, Eucalyptus grandis and bamboo. The results were compared to those from the traditional hydrolysis protocol. Sugar monomers were quantified by 1H NMR and high performance liquid chromatography (HPLC) and there were no significant differences between the two techniques. The new and traditional hydrolysis protocols gave nearly identical results for the bagasse and bamboo samples both of which contain <0.10 uronic acids per xylose unit. However, the new protocol gave a higher xylan yield (13.2% vs. 12.1%) for the E. grandis that contained >0.20 uronic acids per xylose units. For both hydrolysis protocols, summative analyses in the range of 97.5–101.0% were obtained for the three biomass samples. However, the range was narrower (98.6–99.5%) for the new hydrolysis protocol coupled with 1H NMR analysis.