The oxidizabilities of the principal lignocellulose feedstock constituents (cellulose, lignin, xylan) and feedstock exposed to gamma-radiation are investigated. The oxidizability of wheat straw by hydrogen peroxide increases if the absorbed gamma-radiation dose is increased to 200-300 kGy and the feedstock particle size is reduced to 0.8-1.2 mm. Hemicelluloses are practically completely degraded by catalytic peroxide treatment (mass loss of similar to 95%) whereas lignin is destroyed much less (mass loss of similar to 27%) under the same conditions. Pretreatment of the feedstock increases the cellulose content in the lignocellulose feedstock and can be used to produce biofuels (EtOH or 2,5-dimethylfuran).