The structures of elymoclavine-O^-D-fructofuranoside {!] and a new elymoclavine-0^-D-fructofuranosyl-(2>-*l)-0^-D-fructofuranoside [2} produced in saprophytic cultures of strains Claviceps sp. SD 58 and Claviceps purpurea 88 EP on sucrose medium are described. The structures have been determined on the basis of uv, ms, and 2D-nmr data and a degradation procedure.Elymoclavine-O^-D-fructoside has been isolated from a saprophytic culture of Claviceps strain SD 58 by Floss et al. ( 1). This alkaloid was formed from elymoclavine and from the sucrose present in the medium by the action of the enzyme invertase present in the fungal mycelia. Invertase transferred the fructose moiety from sucrose to the hydroxyl group of elymoclavine. The invertase (fructosyl transferase) activity was most probably responsible for the formation of oligosaccharides in submerged cultures of C. purpurea grown on a sucrose-ammonia medium in aerated fermentors (2). These oligosaccharides contained D-glucose as the reducing unit and one, two, and three 0-ß-D-fructofuranosyl units.The present report deals with structure determination and production of natural elymoclavine fructosides 1 and 2 under conditions of submerged fermentation. EXPERIMENTALStrains.-The strain Claviceps sp. SD 58 (ATCC 26019), deposited in the Collection of Microorganisms, Institute of Microbiology, Czechoslovak Academy of Sciences, was obtained from Prof. J.A. Anderson

A non-mutant saprophytic strain C. paspali which forms conidia both on a solid medium and during submerged fermentation is described. Conidiation proceeded in parallel with culture growth and production of alkaloids. The effect of composition of culture media on the intensity of conidiation is described.

Transformation of extracellular sucrose during cultivation of Claviceps purpurea led to the formation of mono-and oligosaccharides. Maltose was a suitable substrate for submerged fermentation of alkaloids. Fermentation in a medium with maltose was characterized by an insignificant formation of glucans, intensive sporulation, suspension growth of mycelium, and a higher formation of elymoclavine. Glucose alone yielded low levels of total alkaloids and high glucan formation; on the other hand, glucose promoted the formation of elymoclavine.

In submerged Claviceps cultures the activity of hydroxymethylglutaryl-CoA reductase preceded the increase of alkaloid production and of sterol content. During the first alkaloid phase, cell mevalonate was involved in the biosynthesis of both alkaloids and steroids. In the second production phase, it was predominantly used for alkaloid synthesis. Hydroxymethylglutaryl-CoA reductase appears to be a suitable target for physiological manipulation to increase clavine alkaloid yields.

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