Effect of culture medium composition on Trichoderma reesei's morphology and cellulase production

The objective of this study was to determine how fungal morphology influences the volumetric cellulase productivity of Trichoderma reesei cultured in four media with lactose and lactobionic acid as fed-batch in a 7 L stirred tank bioreactor. The use of a cellulose-yeast extract culture medium yielded the highest enzyme production with a volumetric enzyme activity of 69.8 U L-1 h(-1), and a maximum fungal biomass of 14.7 g L-1. These findings were associated with the following morphological characteristics of the fungus: total mycelia was 98% of total mean projected area, mean hyphae length of 10 mm, mean hyphae volume of 45.1 mm(3), mean hyphae diameter of 7.9 mu m, number of branches 9, and number of tips per hypha 29. A positive correlation was found between the total mycelia, the number of tips and the volumetric enzyme productivity, indicating the weight of these variables on the enzyme productivity. (C) 2009 Elsevier Ltd. All rights reserved.