Cyclodextrins are cyclic, nonreducing oligosaccharides composed of six, seven of eight glucose units linked by α-1,4-bonds. The ability to form inclusion complexes with hydrophobic molecule is of potential industrial importance.Cyclodextrins are produced from starch by the action of an enzyme commonly known as cyclodextrin glycosyl transferase (E.C.2.4.19). Since the discovery fo cyclodextrin in 1891 by Viller, manymicroorganisms which produce CGTase were isolated from soil, but most of them are patented and their fermentational properties were not known well.
For the efficient production of CGTase from Bacillus macerans, the study on optimization of culture medium was carried out and the composition of optimized culture medium were as follows; soluble starch 2.5%, yeast extract 0.5%, neopeptone 0.5%, $K_2HPO_4$ 0.15%, $MgSO_4$ 0.02%. The optimal culture temperature of Bacillus macerans IFO 3490 was 37℃. the pH of culture medium appeared important factor for the production of CGTase, and the optimum pH was 7. The C/N ratio was very important to CGTase production and its optimum value was 2.5:1(carbon source:organic nitrogen source). The effects of the rate of aeration and agitation on the production of CGTase were investigated. In highly aerated and agitated system(3vvm, 400rpm), the maximum production yield were obtained.
Bacillus macerans로 부터 싸이클로덱스트린 글리코실트랜스퍼라제의 생산을 최대로 하기 위한 발효 조건의 최적화 연구를 수행 하였다. 효소의 생산은 대수증식기 후반에 많았으며, mixed-growth associated 생산 유형을 보였다. 배지의 pH는 균이 증식함에 따라 초기에 감소하다가, 대수증식기를 지나면서 균이 분해 됨에따라 다시 증가하는 유형을 보였다. 효소비생산속도 최대점과 pH 최저점은 일치하였다.
탄소원으로는 Soluble starch가 가장 좋았으며 유기질소원으로는 Yeast Extract와 Neopeptone을 혼합 사용할 때가 가장 좋았다. 특히 탄소원과 유기질소원의 비율이 중요하였으며 그 최적 값은 2.5:1이였다. 무기질소원은 배지의 pH에 영향을 미침에 따라 효소 생산에 영향을 주었으며, 무기염류로는 $K_2HPO_4$ 와 $MgSO_4$가 효과가 있었다. 최적 pH는 7이었으며, 최적 배양 온도는 37 도 였다. 통기 및 교반 조건도 효소 생산에 영향을 미쳤으며 최적 조건은 3vvm, 400rpm, 이였다.
