o:38886 Unveiling the Bioactive Potential of the Aerial Parts of Balkan Achillea clypeolata Comparison with Officinal Achillea millefolium en Background/Objectives: Achillea millefolium is a well-known medicinal plant recognized in several pharmacopeias, while the Balkan endemic species Achillea clypeolata lacks a pharmacopeial monograph and remains insufficiently studied despite its traditional use. This study aimed to comparatively evaluate the phytochemical composition and biological potential of both species. Methods: Chemical composition was studied using UHPLC-MS/MS, HPLC, and FT-IR; anti-inflammatory potential was analyzed by erythrocyte membrane stabilization assay (heat- and hypotonicity-induced hemolysis); and enzyme-inhibitory activity was tested against collagenase, elastase, hyaluronidase, and tyrosinase. In addition, antioxidant activity was evaluated using DPPH, ABTS, and DCFDA assays; antimicrobial activity was determined using the broth microdilution method; and cytotoxic potential was investigated by the MTT assay. Results: The major constituents in water–ethanolic extracts were quinic acid derivatives, flavonoids, phenolic acids, and coumarins, with chlorogenic acid, 3,5-dicaffeoylquinic acid, cosmosiin, cynaroside, rutin, and hyperoside as dominant in both species. Extracts exhibited marked anti-inflammatory activity, where A. millefolium provided greater protection under heat-induced hemolysis, and both extracts showed comparable efficacy under osmotic stress. Concentration-dependent inhibition of collagenase, elastase, hyaluronidase, and tyrosinase (concentration from 62.5 to 1000 µg/mL), along with significant antioxidant activity in ABTS and DPPH assays, was observed. In MRC-5 cells, the extracts reduced AAPH-induced ROS levels up to 50 µg/mL, while higher concentrations showed diminished effects. Moderate cytotoxicity was observed, with A. clypeolata displaying stronger effects at 50–100 µg/mL. Both Achillea species exhibited broad-spectrum antimicrobial activity, with pronounced effects against Gram-positive bacteria. Conclusions: The results support the traditional use of Achillea species and highlight A. clypeolata as a promising, yet underexplored, source of bioactive compounds for dermatological and pharmaceutical applications. chlorogenic acid; UHPLC-MS/MS; skin; anti-inflammatory; collagenase; elastase; hyaluronidase; tyrosinase 1552099 https://doi.org/10.3390/pharmaceutics18050591 2026-05-12T08:21:39.190Z 44 yes 46 Katarina Šavikin Institute for Medicinal Plants Research “Dr Josif Pančić”, Belgrade, Serbia Aleksandra A. Jovanović University of Belgrade, Institute for the Application of Nuclear Energy INEP, Serbia doktor tehnoloških nauka person 0000-0001-5394-0125 Andrea Pirković University of Belgrade, Institute for the Application of Nuclear Energy INEP, Serbia doktor bioloških nauka person 0000-0002-1182-4895 Ana Alimpić Aradski Institute of Botany and Botanical Garden, “Jevremovac”, University of Belgrade-Faculty of Biology, Belgrade, Serbia person Jelena Živković Institute for Medicinal Plants Research “Dr Josif Pančić”, Belgrade, Serbia person Tatjana Stević Institute for Medicinal Plants Research “Dr Josif Pančić”, Belgrade, Serbia person Antoaneta Trendafilova Institute of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, Sofia, Bulgaria; Centre of Competence “Sustainable Utilization of Bio-Resources and Waste of Medicinal and Aromatic Plants for Innovative Bioactive Products” (BIORESOURCES BG), Sofia, Bulgaria person application/pdf 1745333 https://phaidrabg.bg.ac.rs/o:38886 no yes 16 70 92000001 11A29 11A02 11A0215 Unveiling the Bioactive Potential of the Aerial Parts of Balkan Achillea clypeolata: Comparison with Officinal Achillea millefolium 591 18 5 Pharmaceutics Basel, Switzerland MDPI 2026