Chemical Composition and Antioxidant Activity of Essential Oil and Hydrosol Extract Obtained by Hydrodistillation (HY) and Liquid–Liquid Extraction (LLE) of Psoralea bituminosa

ABSTRACT

Chemical composition of essential oil and hydrosol extract obtained by hydrodistillation (HY) and liquid–liquid extraction (LLE) of Psoralea bituminosa was investigated using gas chromatography/retention indices (GC/RIs) and GC-mass spectrometry (GC-MS), and their antioxidant activity determined. Twenty-seven compounds amounting to 92.3% with yield 0.3% were identified in the essential oil extracted from the aerial parts of P. bituminosa. The major compounds identified in the essential oil were E-β-caryophyllene (19.8%), caryophyllene oxide (15.2%), (Z)-phytol (14.2%), (E)-phytol (11.5%) and β-copaene (9.2%). Oxygenated sesquiterpenes were the dominant class of hydrosol extract and accounted for 90.8%. The major components in the hydrosol extract were caryophyllene oxide (35.5%), (E)-phytol (25.6%), τ-cadinol (9.9%) and α-cadinol (8.5%). The essential oil and hydrosol extracts demonstrated antioxidant activity with IC₅₀ of 3.1 and 2.6 mg.L^–1, respectively.

KEYWORDS:

• Caryophyllene
• phytol