Phenolic Profile and Biological Evaluation of Salvia ceratophylloides Ard.: A Novel Source of Rosmarinic Acid

Salvia ceratophylloides Ard. ( Sc ), a rare endemic species from Southern Italy, has been chemically unexplored. We report the first analysis of its polyphenolic profile, antioxidant potential, and preliminary toxicity, compared with the well‐studied Salvia officinalis L. ( So ). Plants were cultivated under identical Mediterranean conditions to minimize variability. Leaf hydroalcoholic extracts were examined for polyphenols (high‐performance liquid chromatography with photodiode array detection and electrospray ionization mass spectrometry [HPLC‐PDA/ESI‐MS]), antioxidant activity (2,2‐diphenyl‐1‐picrylhydrazyl [DPPH], reducing power, Fe 2+ chelation), and toxicity ( Artemia salina lethality bioassay). Although differing qualitatively, both species showed nearly identical total phenolic content ( So 274.59 mg/g; Sc 274.27 mg/g). Notably, Sc was rich in rosmarinic acid and consistently exhibited superior antioxidant activity. It was also nontoxic against A. salina , in contrast to So (LC 50 = 79.27 ± 11.62 µg/mL). These findings highlight Sc as a promising source of bioactive compounds and warrant further pharmacological and conservation studies.