Chicoric acid from Syringodium filiforme

Detrital and living leaves of the tropical seagrass Syringodium filiforme Kütz. were screened for their phenolic contents. For the first time, the major polyphenols were identified, as chicoric acid (CA) and caftaric acid (CAF), by means of NMR and LC/MS. They were quantified in methanolic and aqueous crude extracts using HPLC. Highest amounts were obtained for extracts sequentially prepared under reflux of methanol, then aqueous-methanol. The concentrations found, respectively, ranged from 0.51 to 1.68 mg (g dw⁻¹) for CAF and 0.94–5.26 mg (g dw⁻¹) for CA (of plant dry mass g dw)⁻¹. This is the first report of CAF in a seagrass and CA in S. filiforme. Considering the demonstrated therapeutic applications of CA, its high value-added on the nutraceutical market, and its rare occurrence in the plant kingdom, the significant content found in S. filiforme leaves makes this abundant renewable raw material of interest for the pharmaceutical and food industries.