Practical production of
amanitins was attempted by fermentation using a basidiomycete, Galerina fasciculata GF-060. In liquid fermentation, intracellular alpha- and gamma-
amanitins were the main products, while alpha- and beta-
amanitins accumulated in solid cultured mycelia. The production of
amanitins in liquid fermentation was strongly affected by the amount of the remaining
carbon sources (particularly
glucose and
sucrose). In batch cultivation, the productivity of
alpha-amanitin was 1.58 mg/l. To improve the productivity, replacement cultivation using
glucose-free medium was attempted. As a result, the maximum production of
alpha-amanitin reached 5.02 mg/l. These conditions (fermentation style and
glucose starvation) are effective for the production of all the known types of
amanitins.