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

## TL;DR

A rare Italian sage species is found to be rich in rosmarinic acid and shows strong antioxidant properties with no toxicity.

## Contribution

This is the first study to analyze the chemical profile and biological activity of Salvia ceratophylloides.

## Key findings

- Sc and So have nearly identical total phenolic content.
- Sc is rich in rosmarinic acid and shows superior antioxidant activity.
- Sc is non-toxic to Artemia salina, unlike So.

## Abstract

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, Fe2+ 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 (LC50 = 79.27 ± 11.62 µg/mL). These findings highlight Sc as a promising source of bioactive compounds and warrant further pharmacological and conservation studies.

Among the various extraction techniques investigated, the methanolic ultrasound‐assisted extract (MGME‐UAE) of Micromeria graeca L exhibited the strongest bactericidal effect, selectively inhibiting Proteus mirabilis (inhibition zone 12.7 ± 0.6 mm; MIC = 6.25 mg/mL). Sagerinic acid (30.37 ± 0.70 mg/g), 5‐caffeoylquinic acid, and caffeic acid, were determined by LC‐PDA/ESI‐MS as the major constituents. MGME‐UAE increased membrane permeability, causing significant leakage of DNA/RNA and proteins.