Dynamic changes of yield and cichoric acid content in Echinacea purpurea at different harvest time Influence of microfertilizers on yield and seed production of Echinacea purpurea Progress in identification of three plants of Echinacea Moench.and their active constituents and biotechnology Determination of Cichoric Acid in Echinacea purpuea Simultaneous determination of seven components in Pudilan Xiaoyan oral liquid by HPLC Isolation and purification of cichoric acid from extracts of Echinaceapurpurea by polyamide column chromatography Determinationofcichoricacid,caffeicacid,andchlorogenicacidinTaraxaci Herba by HPLC Determination of cichoric acid in Enchinacea purpurea and its preparation by HPLC Assaying of cichoric acid in introducing plant of Echinacea purpureaa Dynamic changes of yield and cichoric acid content in Echinacea purpurea at different harvest time