麹菌に関する研究

人工変異による酵素力の変化並に強力蛋白分解菌の造成

抄録

(1) Proteolytic, liquefying and saccharifying activities were tested about 202 induced mutants of Aspergillus sojae (mold for soy making).
(2) More than 70 per cent of the mutants decreasedenzymic activities, but some mutants which increased the activities were isolated. A mutant (X-816 strain) was obtained from normal type, which had extremely strong enzymic activities though it was almost the same as the parent strain in appearence.
(3) There was no relation between colony type and enzyrnic activities except that there was hardly any difference in enzymic activities among the mutants that differred the color each other, and that there were the bounds of possibility increasing its saccharifying power in sterile and floccose types.
(4) Mutant strain X-816 having the highest ability of proteolytic activity in the mutants was not inferior to those groups of the natural ranking with the highest position in the activity.
(5) The strain X-816 having higher ability of proteolytic activity was irradiated with ultraviolet for the purpose of increasing the ability. However, favourable results was not obtained.