Continuous cultivation of Trichoderma viride on cellulose

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).