초록
${eta}$-Mannan polymer 분해 효소를 다랑 생산하는 균주를 토양으로부터 분리하고 분리균의 형태적 내지는 생화학적 특성을 조사 분석하여 Sporolactobacillus sp. M201로 동정하였다. Sporolactobacillus sp. M20l 분리균은 locust bean gum을 탄소원으로 사용, 배양했을 때 세포외 ${eta}$-mannanase그리고 세포내 ${eta}$-mannosidase와 ${alpha}$-galactosidase을 다량 생산하는 것으로 확인되었다. 효소 생산 최적 배지와 최적 배양 조건은 ${eta}$-mannanase 생산에는 2.0% locust bean gum, 0.5% peptone, 0.2% KH$_2$PO$_4$, 80 mg/l MgSO$_4$ 및 8 mg/l ZnSO$_4$ 배지 (pH 6.0)와 37$^{\circ}C$이었고 그리고 ${eta}$-mannosidase 생산은 질소원으로 peptone 대신 0.5% yeast extract를 첨가한 상기 배지(pH 5.0)와 3$0^{\circ}C$에서 배양했을 때 가장 높았다. 이상의 각 효소의 최적 생산 조건에서 각각 30시간과 24시간 진탕배양 했을때 ${eta}$-mannanase(10.6 units/ml)와 ${eta}$-mannosidase(1.35 units/ml)의 최고 생산량을 나타내었다.
A bacterial strain producing high levels of an extracellular ${eta}$-mannanase and intracellular ${eta}$-mannosidase and ${alpha}$-galactosidase was isolated from soil. The strain isolated was identified as a strain of Sporolactobacillus sp. and designated as Sporolactobacillus sp. M20l. Synthesis of ${eta}$-mannanase by Sporolactobacillus sp. M20l was induced by sucrose, maltose, or locust bean gum. The highest induction rate was obtained with 2% locust bean gum added to the culture medium as a sole carbon source. On the other hand, induction of ${eta}$-mannosidase was observed only with locust bean gum. The optimal media for the enzyme production were established as follows: for ${eta}$-mannanase; 2% locust bean gum, 0.5% peptone, 0.2% KH$_2$PO$_4$, 80 mg/l MgSO$_4$, and 8 mg/l ZnSO$_4$ (pH 6.0), and for ${eta}$-mannosidase; 2% locust bean gum, 0.5% yeast extract, 0.2% KH$_2$PO$_4$, 80 mg/l MgSO$_4$, and 8 mg/l ZnSO$_4$ (pH 5.0). The optimal culture temperatures for production of ${eta}$-mannanase and ${eta}$-mannosidase were found to be 37$^{\circ}C$ and 3$0^{\circ}C$, respectively. Under the optimal culture conditions, the production of ${eta}$-mannanase and ${eta}$-mannosidase reached the highest levels of 10.6 units/ml and 1.35 units/ml after 30 h and 24 h cultivation, respectively.