[Optimization of Bacillus intermedius cultivation conditions to increase biosynthesis of alkaline extracellular...

The effect of changes in the concentrations of peptone and glucose in the growth medium, the level of aeration and the original pH value on the biosynthesis of RNAase by Bacillus intermedius 7P was studied by means of a multifactor experiment. The optimal medium for the enzyme accumulation contains from 1.2 to 1.4% of glucose and from 2.8 to 3.1% of peptone, and is characterized by the original pH value of 8.45 to 8.7 and the aeration level of 1 : 7.5. The original pH value of the medium that is optimal for the enzyme biosynthesis is not optimal for the cultural growth. Under the optimized conditions of cultivation, the RNAase activity of Bac. intermedius 7P increases by 50 to 60%.