Saccharification of lignocellulose

The increasing energy demand and the anticipated decline in crude oil production has led to an immense search for new energy sources. Plant cell walls contain lignocellulose that conserve great amounts of energy. These polysaccharides are of high importance for the search of renewable energy sources. Pretreatment of the cell wall is necessary in order to hydrolyse it to its component sugars. Once degraded to monomeric sugars it can be fermented to either ethanol or biogas through established fermentation technologies. The aim of this thesis was to compare and evaluate some of the methods used for sacchrification of lignocellulose. Three treatments where compared to determine which is highest yielding. These are enzymatic hydrolysis, microwave irradiation and steam explosion. Wheat straw was used as substrate and hydrolysed by three commercial enzyme mixtures. Samples were pretreated before the enzymatic reaction with either microwave or steam explosion. Results showed that a treatment of either microwave irradiation or steam explosion combined with enzyme hydrolysis gives the highest yield in monomeric sugars. The conclusions that can be drawn are that mechanical pretreatment increases yield drastically but is insufficient in its self. Further enzymatic treatment of wheat straw is necessary to obtain high amounts of simple sugars. sockerarter från lignocellulosa.