Caffeoylquinic acids from leaves of Etlingera species (Zingiberaceae)

Abstract 3- O -caffeoylquinic acid, 5- O -caffeoylquinic acid (chlorogenic acid), and 5- O -caffeoylquinic acid methyl ester, as elucidated by 1 H and 13 C NMR, were isolated from leaves of Etlingera elatior . This is the first report of caffeoylquinic acids (CQA) including chlorogenic acid (CGA) in Zingiberaceae. Leaves of Etlingera species were rich in total phenols and CQA, and non-cytotoxic to normal human liver and African green monkey kidney cells. Content of CQA of E. elatior , Etlingera fulgens , and Etlingera rubrostriata leaves was significantly higher than leaves of Ipomoea batatas , and comparable to flowers of Lonicera japonica . CGA found only in leaves of E. elatior and E. fulgens was significantly higher in content than flowers of L. japonica , the commercial source.