Abstract: | A process for manufacturing disodium 5′-guanylate was devised. 5′-Amino 4-imidazole carboxamide riboside (AICA-R) was accumulated with an amount over 100 times those reported in the literature by fermentation of D -glucose with a non-exacting purineless mutant derived from Bacillus megaterium JAM 1245) by x-ray irradiation. The influence of RNA, amino acids, and salts on AICA-R accumulation was clarified. Appropriate aeration and agitation was found necessary. The (60-hr, cultivation of the medium containing 8% of D -glucose gave AICA-R in the concentration above, 11 g/l. AICA-R thus accumulated was separated from the fermentation broth by ion-exchange technique and subjected to synthetic processes to yield disodium 5′-guanylatc with the yield over 40%, based on AICA-R. |