Influence of phenological stage on chemical composition and antioxidant activity of Salvia lavandulifolia Vahl. essential oils

Abstract

The influence of phenological stages (vegetative and full flowering stages) on chemical composition and antioxidant activity of essential oils of Salvia lavandulifolia were investigated. GC analysis of the essential oil samples pointed to a quantitative variability of components; terpene hydrocarbons derivatives predominate at the vegetative stage whereas oxygenated derivatives are the main components in essential oil samples from plants at the full flowering stage. Moreover, ORAC assay, used for measuring the peroxyl-radical scavenging capacity, revealed that the essential oil samples from plants collected at the full flowering stage possessed the most potent antioxidant potential. Furthermore, this study assessed whether the investigated essential oil samples protect the human astrocytoma cell line from H2O2-induced oxidative stress. This paper reports that pretreatments with essential oils from both phenological stages exerted a cytoprotective effect by increasing cell viability, recovering changes in cell morphology and in GSSG/GSSG+GSH ratio, inhibiting lipid peroxidation and caspase-3 activation and inducing antioxidant enzymes expression and activity. Essential oils samples from full flowering state versus flowering stage at the concentration of 50μg/mL were the most effective in conferring protection. On the basis of these results, S. lavandulifolia essential oils as antioxidants are of interest for its use for industry and human health purposes.