Method for controlling the amount and the ratio of amounts of alkaloids produced in fermentation

摘要

The method controls the amount and the ratio of the amounts of ergot alkaloids produced by variant strains of Claviceps purpurea under saprophytic conditions. The strains of Claviceps purpurea used for this are those which produce mainly ergocornine and alpha - and beta -ergocryptine. The regulator used is a compound which functions as precursor in the biosynthesis of isoleucine or a compound which, as a result of biochemical control, stimulates the formation of isoleucine. These compounds - methyloxylacetic acid, alpha -ketobutyric acid, threonine and/or homoserine or homocysteine and/or methionine - are employed in an amount of 0.01-10 kg/m<3> of fermentation broth. The method results in a higher total alkaloid concentration in the fermentation broth, and the ratio of the amounts of alpha - and beta -ergocryptine is more favourable.