Caffeic acid derivatives from a hairy root culture of Lactuca virosa

In a search for biologically active phenolics, a hydroalcoholic extract from the hairy roots of Lactuca virosa was fractionated by chromatographical methods. The procedure led to the isolation of a substantial amount of 3,5-dicaffeoylquinic acid (3,5-DCQA)—a potent free radical scavenger. An analytical RP-HPLC separation of the hydroalcoholic extract from the hairy roots allowed identification of further hydroxycinnamates: caftaric acid (CTA), chlorogenic acid (5-CQA) and cichoric acid (DCTA), as well as small amounts of unbound phenolic acids. A time course of growth and caffeic acid derivatives accumulation in the hairy root culture was also investigated. The highest contents of the compounds in the examined roots were detected at the logarithmic phase of growth. The average content of 3,5-DCQA in the roots (ca. 2.5% DW) was at least one order of magnitude higher than that found in roots of Lactuca species and callus culture of L. virosa.