Abstract
1. Two high molecular substances, D-1 and D-2 described in this paper, were isolated from natural saké and identified chemically as some kinds of mucoprotein (N-containing polysaccharides).
2. Preparing antiserum reacting with D-complex (D-1 and D-2), the amount of D-equivalent substance contained in commercial saké was determined serologically.
3. The protein turbidity producing substances in saké were identified as D-complex; when the content exceeded 0.015% the turbidity phenomenon occurred.
4. Most Aspergillus fungi produced D-complex even in synthetic media, but the fungi belonging to Penicillium, Mucor, and Rhizopus did not.
5. The role of D-complex in saké taste was discussed.
