qThe culture used wheat bran as media for four kind of mold strains such as Aspergillus oryzae, Aspergillus kawachii, Aspergillus usamii and Rhizopus javanicus to examine which strain could higher the activity of amylase most which is used for alcohol fermentation.
It also provided three different kind of wheat bran media containing starch of 47%, 51% and 55% respectively for each strain. For each media it also added three different kind of nitrogen sources; ammonium sulfate, casein, and ammonium sulfate and casein equally mixed. Each nitrogen source added was subordinately differentiated into three different percentages, 2%, 4% and 6% respectively, except the 2% for the ammonium sulfate.
The results obtained were summarized as follows
(1) The activity of α-amylase was highest in the media of starch value 47% of wheat bran with 6% of casein added.
(2) The activity of β-amylase was highest in the media of starch value 51% of wheat bran with 2% of the equal mixture of ammonium sulfate and casein added.
(3) The activities of both α-amylase and β-amylase of Aspergillus usamii were highest in the media of starch value 47/ wheat bran with no addition of nitrogen source.
(4) Of the four strains examined, the activities of α-amylase and β-amylase cultured in Rhieopus javanicus were both relatively higher.
(5) The activities of α-amylase and β-amylase of the strains examined became lower as the percentage of starch contents increased except in Rhizopus javanicus.
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