Essential oils from Salvia marashica and Salvia multicaulis as natural ingredients: phytochemical composition, antioxidant activity, enzyme inhibition, and molecular docking studies

The increasing prevalence of neurodegenerative and metabolic disorders underscores the need for safe, natural, and multifunctional bioactive agents capable of modulating oxidative stress and key metabolic enzymes. In this study, the chemical composition and in vitro biological activities of essential oils obtained from the aerial parts of Salvia marashica and S. multicaulis were investigated. The essential oils were extracted by hydrodistillation and characterized using GC–MS analysis. Eucalyptol (20.68%) and α-terpineol (11.16%) were identified as the major constituents of S. marashica , whereas S. multicaulis was rich in camphor (16.04%) and eucalyptol (13.34%). Antioxidant activities were evaluated using DPPH, ABTS, FRAP, and CUPRAC assays, revealing that S. marashica essential oil exhibited higher antioxidant potential in most assays. Enzyme inhibition studies showed that S. marashica essential oil exerted stronger inhibitory effects against acetylcholinesterase and butyrylcholinesterase (IC₅₀ = 114.579 and 138.028 µg/mL, respectively), indicating potential relevance for Alzheimer’s disease–related enzyme modulation. In contrast, S. multicaulis essential oil demonstrated more potent α-glucosidase inhibition (IC₅₀ = 77.270 µg/mL), suggesting promising antidiabetic potential. To support the experimental findings, molecular docking studies were performed on 52 identified constituents against α-amylase, α-glucosidase, acetylcholinesterase, butyrylcholinesterase, and tyrosinase. Oxygenated sesquiterpenes, particularly β-eudesmol, cubedol, and caryophyllene oxide, showed the strongest binding affinities, providing a molecular rationale for the observed activities. This study presents the first report on the chemical composition and biological activities of S. marashica essential oil and the first evidence of the antidiabetic potential of S. multicaulis essential oil, highlighting their potential as natural multifunctional bioactive agents.