Biotransformation of 5βH-pregnan-3βol-20-one and cardenolides in cell suspension cultures of Nerium oleander L.

In order to demonstrate enzyme activities playing a role in the biosynthesis of cardenolides and 2,6-dideoxysugars, 5βH-pregnan-3βol-20-one and cardenolides (digitoxigenin, oleandrigenin/L-oleandrose, oleandrin, neriifolin, digitoxigeninmonodigitoxoside and strospeside) were fed to cell suspension cultures of Nerium oleander L.. It could be shown that cell suspension cultures of Nerium oleander L. are able to oxidize, isomerize and glucosylate 5βH-steroidaglycones at C-3. The respective glucosides of the 5βH-steroid-aglycones are the main biotransformation products. These cell cultures are an appropriate tool for the production of labelled 5βH-steroidglucosides.