(E)-p-coumaroyl-1-O-beta-D-glucopyranoside accumulation in roots of Plantago lanceolata cultures

Biotransformation of 1 mM (E)-cinnamic acid by thirty-day-old whole ribwort s (Plantago lanceolala) was investigated. After addition of this caffeic ac id precursor in medium culture, the root accumulation of the two main caife ic acid glycoside esters (CGEs), plantamoside and verbascoside was compared with in vitro ribwort control. No major modification of these two CGEs sto rage was highlighted, p-Coumaroyl-glucose and feruloyl-glucose were neo-syn thesized and accumulated in the roots of seedlings fed with cinnamic acid. Maximum level of p-coumaroyl-glucose was higher than those produced by seve nty-five-day-old ribworts previously investigated. Hence, the complete stru cture of the latter glucosylated acid was determined by both H-1 and C-13 N MR spectroscopy as (E)-p-coumaroyl-1-O-beta-D-glucopyranoside.