[Effect of the composition of the nutrient medium on the synthesis of acid-fast alpha-amylase by different strains of Aspergillus].

The capacity of 86 strains of the Aspergillus fungus to synthesize acid stable alpha-amylase was examined. The strains of Asp. niger showing a high capacity of synthesizing the enzyme were isolated. Repeated cultivation of the selected cultures on the Minoda agar medium led to a 200% increase in the enzyme activity in the submerged culture. Addition of sodium nitrate to the Minoda medium during submerged cultivation allowed a 3-fold increase of the synthesis of acid stable alpha-amylase.