Antioxidant and antimicrobial properties of a new chemotype of woodland sage (Salvia nemorosa L. subsp. nemorosa, Lamiaceae) essential oil

Abstract

Essential oil of woodland sage (Salvia nemorosa subsp. nemorosa L., Lamiaceae) was analyzed using gas chromatography–mass spectrometry, and assayed for antimicrobial and antioxidant activities. Antioxidant activity was evaluated by measuring both free radical scavenging capacity (RSC) and lipid peroxidation (LP) effects. Specifically, RSC was assessed by measuring the scavenging activity of essential oils on 2,2-diphenyl-1-picrylhydrazil (DPPH) and hydroxyl radicals; while LP effects were evaluated by monitoring the activities of essential oil in Fe²⁺/ascorbate and Fe²⁺/H₂O₂ induction systems. The investigated essential oil reduced DPPH (IC₅₀ = 0.98 μl/ml) and OH radical formation (IC₅₀ = 0.11 μl/ml) in a dose-dependent manner. Strong LP inhibition in both induction systems was also observed. Antimicrobial activity was tested against 13 bacterial strains and 6 fungi, including Candida albicans and 5 dermatomycetes. Although only weak antifungal activity was found; significant antibacterial activity was observed against Salmonella typhi, Shigella sonei and Staphylococcus epidermidis.