Production of NAD from adenine and nicotinamide by Saccharomyces sake KBA No.6

Saccharomyces sake KBA No. 6에 의한 adenine과 nicotinamide로부터 nicotinamide adenine dinucleotide(NAD)의 생산

In order to produce nicotinamide adenine dinucleotide (NAD) which is a pyridine nucleotide coenzyme, Saccharomyces sake KBA No. 6 having high NAD content was selected from 12 strains of yeast and various factors affecting the production of NAD were investigated. For NAD production, 4% of glucose was effective as a carbon source and 2% of bactopeptone was the best nitrogen source. The optimum pH and temperature was 5.0 and $30^{\circ}$, respectively. Also, when 4 mg/ml of nicotinamide and 3 mg/ml adenine were used as precursors simultaneously, NAD production was the best. To increase NAD production, 2 valence metal ions were used during cultivation and $Zn^{2+}$ was very efficient. Among the surface active agents, anionic sodium dodesyl sulfate (SDS) was effective. Under the optimum conditions, the maximum amount of produced NhD was 35 mg/100 ml medium after cultivation of 144 hrs and 89% of total NAD amount, 31 mg of NAD, was leaked into culture broth.

미생물을 이용하여 pyridine계 보효소인 NAD를 생산하기 위하여, 12종의 효모로부터 NAD 함량이 높은 Saccharomyces sake KBA No. 6을 선별하였으며, NAD 생산에 미치는 여러 가지 효과를 검토하였다. NAD 생산에 있어서 탄소원으로는 4% glucose, 질소원으로는 2% bactopeptone이 가장 좋았으며 최적 PM와 온도는 각각 5.0과 $30^{\circ}$C$이었다. 한편 NAD 전구물질로서 nicotinamide와 adenine을 동시에 사용한 경우 NAD 생산이 가장 좋았으며 이때의 농도는 각각 4 mg/ml과 3 mg/ml이었다. 또한 NAD 생산을 증가시키기 위하여 배양시 2가 금속이온들을 사용하였으며 이들 중 $Zn^{2+}$가 매우 효과적이었다. 계면활성제의 영향은 음이온 계면활성제인 sodium dodecyl sulfate(SDS)를 사용하였을 때 효과적이었다. 상기의 최적 조건하에서, 144시간 배양 후에 최대 NAD 생산량은 배지 100 ml당 35 mg이었으며 전체량의 89%인 31mg의 NAD가 배지 중에 유리되었다.