By irradiation of UV rays and ^60Co-r rays on Aspergillus awamori var. kawachii, the mutant strain which is almost lacking in the ability to produce transglucosidase but is able to produce amylases was isolated. The amount of saccharogenic amylase produced by the mutant strain reduced to half of that produced by the wild strain. On the contrary, the amount of dextrinogenic amylase from the mutant strain increased 3-fold as compared with that from the wild strain. The shaken cultures of the wild strain and the mutant strain were made at 30℃, with the synthetic medium. It was found from paper chromatography that the enzyme from the mutant strain did not change 10% maltose (used as the substrate for transglucosidase) to unfermentable sugars such as isomaltose, panose, and dextrantriose and so on. But the spot of maltotriose was detected on the paper chromatogram of the reaction products obtained with the enzyme from the mutant strain, but not with that from the wild strain.
黒麴菌Aspergillus awamori var. kawachiiにUV,^60Co-γ線を照射してトランスグルコシダーゼをほとんど産生しない変異株を得ることができた.しかしこの変異株は糖化型アミラーゼ力が原株のそれより減少し,逆に液化型アミラーゼ力が原株のそれより増加した.この変異株を合成培地を用い振盪培養を行ない,それより得られた酵素を10%マルトースに作用させた結果,非発酵性糖に相当するスポットはペーパークロマトグラム上では見い出せなかつた.しかし原株の酵素についてはみられないマルトトリオースのスポットが変異株の酵素について検出された.