Advancing the Potential of Ostericum palustre (Besser) Besser (Synonym Angelica pancicii Vandas ex. Velen.) of Bulgarian Origin as a Source of Bioactive Compounds: Metabolite Profiling and Pharmacological Activity

Ostericum palustre (Besser) Besser (synonym Angelica pancicii Vandas ex. Velen.) is a Eurasian species from the Apiaceae family, previously related to the Balkan endemic species A. pancicii. The study aims to provide a thorough profiling of methanol-aqueous extracts from O. palustre leaves, roots, and inflorescences integrated with an evaluation of antioxidant potential and enzyme inhibitory activity towards some therapeutic targets. For the first time, a series of simple coumarins and furanocoumarins alongside phenolic and acylquinic acids, and flavonoids were annotated/dereplicated in the O. palustre of Bulgarian origin by liquid chromatography coupled with quadrupole—Orbitrap high resolution mass spectrometry acquisition platform. According to the discriminant analysis (sPLS-DA) of the biological potential, radical scavenging activity (47.9 mg TE/g in DPPH and 61.8 mg TE/g in ABTS), reducing power (102.2 mg TE/g in CUPRAC and 57.4 mg TE/g in FRAP), and metal-chelating capacity (20.1 mg EDTAE/g) accounted mainly for the stronger antioxidant activity of inflorescences extract than roots and leaves. Root extracts exhibited anti-collagenase, anti-elastase, and anti-hyaluronidase effects with lower IC50 values (IC50 37.22, 42.47 and 32.09 μg/mL, respectively). Pearson relationship analysis revealed potent antioxidants including furanocoumarins (oxypeucedanin hydrate, xanthotoxol/bergaptol, byakangelicin/isobyakangelicin, ostruthol) and phenolic acids, while a series of angelols alongside feruloylquinic and dicaffeoylquinic acids, and flavonol glycosides hold significance for the neuroprotective activity of the leaves extract. The enzyme inhibitory activity of the root extracts towards collagenase, elastase and hyaluronidase, related to the anti-aging activity, was ascribed to simple hydroxylated/methoxylated coumarins. The study suggests the potential health benefits of O. palustre extracts as antioxidant, anti-aging, and neuroprotective agents.