Role of glycols and tweens in the production of ergot alkaloids by Claviceps paspali.

Several glycols and Tweens markedly stimulated the production of ergot alkaloids in submerged cultures of Claviceps paspali. The role of these compounds was investigated in shake flasks and bench-scale fermentors. 2,3-Butanediol was not utilized by the fungus, and 1,2-propanediol-1-(14)C was not incorporated into the alkaloids. Glycols and Tweens lowered the surface tension of the basal medium and promoted the utilization of metabolites. In the presence of glycols and Tweens, an increased uptake of labeled sorbitol and succinic acid took place, whereas the specific radioactivity of the alkaloids was not affected. These results indicated that glycols and Tweens are not involved directly in the biosynthetic process; they apparently acted as surface-active agents, facilitating transport of metabolites into the cells.