Katsuobushi에서 곰팡이, 세균, 효모 등 총 70여 균주를 분리하였으며 이중 곰팡이는 가다랑이 추출물에 밀기울을 가한 배지에서 생육이 양호하였다. protease활성이 높고 고미생성도가 적은 균주는 Aspergillus niger로 동정된 OK-63 strain이었으며 배양 6일만에 균체의 최대증식, protease의 최대 효소활성을 나타내었다. 효소정제는 150배 정제, 활성수율은 45%였으며 polyacryamide gel 전기영동에 의해 단일 band로 확인되었다.
The strain OK-63 isolated from katsuobushi was cultured on wheat bran medium and the isolate was morphologically identified as an Aspergillus niger group and showed maximum pretense activity and multiplication after 6 days of cultivation. Protease was purified by ammonium sulfate fractionation. Sephadex G-100 gel filtration and DEAE-cellulose column chromatography. The purified enzyme showed single band by polyacrylamide gel electrophoresis and the purity was 150 times higer than crude enzyme. The recovery of enzyme activity was found to be 45%.
