Biosynthetic studies of lactucin derivatives in hairy root cultures of Lactuca floridana

Abstract

Biosynthetic studies of the guaianolide-type sesquiterpene lactones 11 βH,13-dihydrolactucin-8- O-acetate and 8-desoxylactucin were performed in Agrobacterium rhizogenes—transformed hairy root cultures of blue-flowered lettuce, Lactuca floridana. The 13C NMR spectra of the two guaianolides labelled by incorporation of [1- 13C], [2- 13C], [1,2- 13C 2]acetate and [2- 13C]mevalolactone showed patterns of enrichment consistent with a previously proposed biogenetic pathway for guaianolide-type sesquiterpene lactones via the acetate-mevalonate-germacradiene route.