A turbidimetric method for the screening of amylase-producing mutants of Aspergillus niger.

The method is based on the assumption that extracellular amylase, which is produced by strains of Aspergillus niger in liquid culture, hydrolyses the starch in the media and brings about a corresponding decrease in the turbidity of the media. Mutant strains which produced different quantities of amylase exhibited different degrees of decrease in turbidity of the media. The results showed that a greater degree of decrease in turbidity was observed for a higher quantity of amylase produced.