| Abstract: | Using ball milled cellulose as the only carbon source Trichoderma viride was grown in a continuous flow culture at pH = 5.0 and T = 30°C. Steady-state values for cell protein, cellulose, and cellulase for different substrate concentrations (4–11 g/liter) and dilution rates (0.033–0.080 hr?1) were obtained. Under steady-state conditions, 50–75% of the cellulose was consumed indicating a critical dilution rate on 0.17 hr?1. Cellulase activity (U/ml) in the fermentation broth increased slightly with increasing substrate concentration and decreased with increasing dilution rate, while the specific cellulase productivity (U/mg cell protein·hr) was fairly independent of the dilution rate, with a maximum around D = 0.05 hr?1. Following step changes in substrate concentration and dilution rate, new steady-state values were reached after three to five residence times (cell protein and cellulose) and four to six residence times (celullase activity). |
