The growth and enzyme production by Trichoderma reesei Rut C-30 using different lignocellulosic materials as carbon source were investigated. Cellulose, sugar beet pulp and alkaline extracted sugar beet pulp (resulting in partial removal of hemicellulose, lignin and pectin) or mixtures thereof were used as carbon sources. It was found that endoglucanase and endoxylanse activities were produced throughout the cultivations, whereas alpha-arabinosidase was induced late during the cultivation. The highest amounts of endoglucanse, could be measured when T reesei Rut C-30 was grown on cellulose or cellulose containing mixtures. Endoxylanase was produced on all substrates, but the presence of cellulose was favourable for the production. Polygalacturonase activity could be measured at high varying levels throughout the cultivations, except during growth on cellulose. The varying levels might originate from the production of different isoenzymes of polygalacturonase. (C) 2003 Elsevier Inc. All rights reserved.