Characterization of Phenolic and Essential Oil Constituents of Satureja boissieri Hausskn. ex Boiss and Evaluation of Antioxidant Potential

This study investigated the chemical composition of the essential oil (EO) and the phenolic profiles of methanol extracts from Satureja boissieri Hausskn. ex Boiss. EO analysis by Gas Chromatography–Mass Spectrometry (GC-MS) identified carvacrol (45.2%), cymene (26.0%) and γ-terpinene (17.5%) as the primary constituents. Phenolic profiles were quantified via Liquid Chromatography–High-Resolution Mass Spectrometry (LC-HRMS), revealing syringic acid (56,647.96 mg/kg extract), rosmarinic acid (47,777.98 mg/kg extract) and hesperidin (6353.49 mg/kg extract) as major components in the extract. The antioxidant potential was evaluated through three distinct radical scavenging assays (DPPH, ABTS and DMPD) and the determination of ferric (Fe3+) and cupric (Cu2+) reducing capacities. Notably, S. boissieri exhibited potent antioxidant activity, with IC50 values of 11.74 µg/mL for DPPH and 9.90 µg/mL for ABTS radical scavenging, demonstrating performance comparable to standard antioxidants such as α-tocopherol (11.31 and 8.37 µg/mL, respectively). Furthermore, the in vitro inhibitory activities against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes were evaluated. While both extracts exhibited similar and significant AChE inhibition (35.3% and 32.4%, respectively), the essential oil was notably more potent against BChE than the methanol extract. These findings suggest that S. boissieri is a significant source of bioactive compounds with promising antioxidant and neuroprotective potential for pharmaceutical applications.