Essential Oil Constituents, Antioxidant and Antimicrobial Activities of Salvia virgata Jacq. from Iran

Abstract

The chemical composition of essential oil isolated by hydrodistillation from the aerial part of Salvia virgata under different ontogenesis (pre-flowering and full-flowering) conditions were determined using Gas Chromatography (GC) and Gas Chromatography-Mass Spectrometry (GC-MS). Twenty nine constituents were identified in S. virgata essential oils under different ontogenesis conditions that represented 98.36 - 99.18 % of the oils. The main components of the oil were β-caryophyllene (24.58-42.54 %), caryophyllene oxide (10.25-19.88 %), sabinene (8.64-19.58 %), 1-Octen -3-Ol (7.54-8.59 %), terpinene-4-ol (4.25-6.64 %) and α-thujene (3.74-6.46 %). The total phenolic content and the antioxidant activity of plant extract were determined by Folin-Ciocalteau and the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assays and ferric reducing antioxidant power (FRAP) assay respectively. Total phenols varied from 21.84 to 24.38 (mg GAE/g dw) and the IC₅₀ in the radical scavenging assay ranged from 22.12 to 24.45 mg/ml and FRAP values ranged form 26.84 to 28.46 μM Quercetin E/g dw. Antimicrobial activity of the essential oil was evaluated using the disc diffusion method. The oils of various ontogenesis conditions showed moderate antimicrobial activity against Staphylococcus aureus and Candida albicans two medically important pathogens.

Keywords:

• Salvia virgata
• Essential oil
• phenolic content
• antioxidant
• antimicrobial activity
• Ontogenesis