Characterization of potentially health-promoting constituents in sea fennel (Crithmum maritimum) cultivated in the Conero Natural Park (Marche region, Central Italy)

Context: Sea fennel (Crithmum maritimum L. [Apiaceae]) is an aromatic herb rich in bioactive molecules, such as polyphenols, with potential positive effects on human health. Objective: This study aimed at the characterization of sea fennel secondary metabolites, focusing on the phenolic fraction. Materials and methods: Samples of whole sprouts, sole leaves and sole stems were subjected to accelerated solvent extraction with methanol, and the resulting extracts were analyzed by high‑performance thin‑layer chromatography, high-performance liquid chromatography, and liquid chromatography coupled with diode array detection and high-resolution mass spectrometry (LC-DAD-HRMS). Results: HPTLC and HPLC analyses of sea fennel extracts showed similar chromatographic profiles among the tested samples, and the prevalence of chlorogenic acid within the phenolic fraction was verified. Ten hydroxycinnamic acids, including neochlorogenic acid, chlorogenic acid, cryptochlorogenic acid, isochlorogenic acid B, isochlorogenic acid A and isochlorogenic acid C, 11 flavonoid glycosides, e.g., rutin, hyperoside, isoquercitrin, two triterpene saponins and two hydroxylated fatty acids, were detected and annotated via liquid chromatography coupled with diode array detection and high-resolution mass spectrometry. Discussion and conclusions: The use of accelerated solvent extraction and LC-DAD-HRMS for the characterization of sea fennel secondary metabolites allowed the annotation of seven compounds newly detected in sea fennel, including triterpene saponins and hydroxylated fatty acids.