Comparison of chemical composition, antioxidant and antimicrobial activity of lavender (Lavandula angustifolia L.) essential oils extracted by supercritical CO₂, hexane and hydrodistillation

Abstract

The study investigated the effects of hydrodistillation, supercritical CO₂ extraction (SCE) and hexane extraction on yield, chemical composition, antimicrobial and antioxidant activities of lavender (Lavandula angustifolia L.) essential oil. The SCE produced yields significantly higher than hydrodistillation and comparable to the yield that of the solvent extraction. The chemical composition of extracts depended on the extraction methods. Linalool, linalyl acetate, camphor and borneol were the most abundant components in all extracts collectively constituting about 80% of the essential oil. Essential oil from SCE was free from thermal degradation and undesired compounds, unlike products of hydrodistillation and hexane extraction. Extracts of SCE and hydrodistillation had higher antimicrobial activity than hexane extracts. The antioxidant activity of SCE extracts significantly higher than the others extracts and was similar to that of standard antioxidant. It can be concluded that SCE is a promising process for the extraction of lavender essential oil.