An investigation on cichoric acid, chlorogenic, caffeic acid content and antioxidant activity in some Iranian native species compared to Echinacea purpurea L. in different developmental stages

Polyphenol and flavonoid compounds, belonging to the medicinal species of Asteraceae family, have been found as natural antioxidants. Cichoric and chlorogenic acid are two caffeic acid derivatives. These polyphenol components, especially cichoric acid, are the dominant components of Echinacea purpurea L. The general goal of this research was to identify Iranian native sources of cichoric acid, chlorogenicacid and also caffeic acid as their precursor. For this purpose, the roots, stems and leaves of five Iranian native species (Lactuca undulata, Lactuca serriola, Leontodon asperrimus, Cichorium intybus and Sonchus oleraceus) were collected during vegetative and reproductive stages from north eastern of Iran. The seeds of E. purpurea were purchased and cultured in greenhouse conditions. The results revealed that the highest amount of cichoric (3.6 mg/g DW) and caffeic acid (28.8 mg/g DW) was observed in E. purpurea roots during vegetative and reproductive stages, respectively. Among Iranian native species, L.undulata stems and L.asperrimus roots had the highest content of cichoric (2.3 mg/g DW) and chlorogenic acid (8.08 mg/g DW) in reproductive and vegetative stages, respectively. The highest antioxidant activity was found in E. purpurea roots during reproductive stage. The lowest level of IC50 was found in E.purpurea roots at reproductive stage. It seems that L. undulata and L. asperrimus could be suitable sources for cichoric, chlorogenic and caffeic acid, compared to other Iranian native species.