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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℃, respectively. Also, when 4 ㎎/㎖ of nicotinamide and 3 ㎎/㎖ 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 NAD was 35 ㎎/100 ㎖ medium after cultivation of 144 hrs and 89% of total NAD amount, 31 ㎎ of NAD, was leaked into culture broth.
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