[Effect of nitrogen sources on cellulase biosynthesis by a mutant strain of Trichoderma viride 44]

The effect of various nitrogen sources on cellulase biosynthesis by the mutant strain Trichoderma viride 44 was examined. This strain may utilized nitrogen in the nitrate, ammonium of organic form. When cultivating this strain, it appears advantageous to add to the nutrient medium yeast and yeast lyzates as well as their mixture with ammonium sulfate. Cellulase reached its maximum activity of 20.2, 21.5 and 23.2 mu/ml when grown on the medium containing ammonium phosphate, peptone and brewing yeast plus ammonium sulfate, respectively. It is useful to apply nitrogen in its organic forms in small quantities and in combination with mineral forms. The nitrogen presence in the medium is necessary only at the exponential stage of fungal growth. The lack of nitrogen in the stationary stage characterized by the maximum cellulase formation does not inhibit an increase in the enzyme activity.