Studies on the Metabolism of Aspergilli

Part VII. Effect of Water Level of Culture Medium on Mycelial Compositions and Enzyme Production

Abstract

Studies were made on the effect of water level of culture medium on the mycelial com-positions and enzyme production in Aspergillus sojae K. S. The mold was grown on the media of various water levels made of powder of defatted soybean and wheat granule.
1. The mycelia grown on the medium of low water level consumed more oxygen and formed less ammonia per mg dry weight.
2. The above mycelia were richer in 2 N H₂SO₄-soluble glycogen, 60% H₂SO₄-soluble carbohydrates, and RNA than those grown on the high water medium during the whole period of incubation.
3. The mycelia grown on the high water medium had a tendency to accumulate AMP, ADP, inorganic phosphorus, fructose 6-phos-phate, ribose 5-phosphate and monophos-phoglycerate according to the lapse of culture time.
4. Production of protease and α-amylase was more remarkable in the mycelia grown on the low water medium than in those grown on the high water medium.