We designed effective method for improving sporulation of koji mold Aspergillus oryzae strains characteristic of low rate of sporulation. NaCl was added to glucose-yeast extract agar media to a concentration of 0, 3, 6,and 9% (w/v). The seven strains were examined in their growth rate and sporulation yield. As a result, the growth rate of all examined strains was maximum at 3% (w/v) NaCl. Moreover, the strain group whose sporulation rate was low at 0% (w/v) NaCl yielded maximum spore at 3% (w/v) NaCl. As consequence, the spore suspension of the strains of low rate of sporulation can be prepared effectively by 3% (w/v) NaCl addition to GYA.
麹菌Aspergillus oryzaeのうち, 低胞子形成株からの効率的な胞子形成能の強化法を開発した. グルコース・酵母エキス寒天培地 (GYA) にNaClを0, 3, 6, 9% (w/v) となるように添加して, 7株の生育及び胞子着生数に与える影響を調べた. その結果, 3% (w/v) NaClにおいて, 全ての菌株の生育速度が最大となった. また, 0% (w/v) NaClの場合に胞子形成が貧弱であった5菌株は, 3% (w/v) NaClの場合に胞子着生数が最大となった. このことから, 麹菌の低胞子形成株は, GYAに3% (w/v) NaClを添加することにより, 効率的に胞子を調製することができると考えられる.