The Influence of NtC3H on the Synthesis of Flavonoids and Chlorogenic Acid in Tobacco

To test whether NtC3H participates in the biosynthesis of flavonoids, and chlorogenic acid (CGA) in tobacco and increases the contents of these secondary metabolites, we constructed the over-expression vector pCXSN::NtC3H and introduced it into Nicotiana tabacum var. samsun via Agrobacterium-mediated transformation. The concentrations of the different secondary metabolites including CGA, rutin, and kaempferol rutinoside in leaves of wild-type and transgenic lines were determined by HPLC. Compared to wild-type samsun tobacco, in transgenic tobacco the concentrations of CGA were increased 3.6-fold, rutin and kaempferol rutinoside were increased 6.1- and 24.6-fold respectively. These results suggested that NtC3H positively regulated the synthesis of flavonoids and CGA in tobacco.