Structure and Properties of Hemicelluloses

“Hemicelluloses represent one of the largest natural resources on Earth. They occur together with cellulose in plant cell walls and the exact structure varies between different types of plants. However, generally they are heteropolysaccharides that are branched and often also acetylated and methylated. The biological background for the structural heterogeneity of hemicellulose is unclear. Hemicelluloses have many applications and they have the potential to be used also in novel types of material. Extraction of hemicelluloses from biomass is a suitable method for producing large amounts of hemicelluloses, but presence of lignin has been an obstacle for high yield extractions. At KTH an enzyme based pre-treatment technology has been developed for improved extraction of hemicellulose from wood.The goal with this project is to increase the understanding of the correlation between the structure of hemicellulose, and its properties and biological function with a purpose to increase the technical usability of hemicelluloses. Hemicelluloses are modified, for example by acetylation, and the solubility will be evaluated. Also the role of the galactose side group for the degradation properties of galactoglucomannan in alkali is studied. Additionally molecular dynamics simulations are used for studying the properties of hemicelluloses.”