Evaluation of the effect of particle size, aeration rate and harvest time on the production of cellulase by Trichoderma reesei QM9414 using response surface methodology

In the present study, the effect of culture conditions on cellulase activities by Trichoderma reesei QM9414 grown on rice bran media in solid-state fermentation was evaluated. Also, the optimum conditions were determined using response surface methodology (RSM). A face center design was used to investigate the effect of independent variables i.e. particle size, aeration rate and harvesting time on filter paper activity (EPA), Avicelase and carboxy methyl cellulase (CMCase) activities. The highest FPA, Avicelase and CMCase activities were 11.648, 99.756 and 94.210 U/g dry weight of substrate (DWS), respectively. The results showed that aeration rate and particle size had significant effects on the activity of cellulase on FPA. Also, particle size and harvesting time had significant effects on the activity of both Avicelase and CMCase. The reduction of particle size and harvesting time to 1-1.5 mm and 4 days, respectively increased cellulase activities. (C) 2009 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.