Analysis of the seasonal variation in chemical profile of piper glabratum kunth essential oils using GC×GC/qMS and their antioxidant and antifungal activities

Abstract

Piper glabratum is a plant native from South America, which has been little studied, despite its use in folk medicine. In this study, chemical composition, antioxidant and antifungal activities of essential oils (EOs) from leaves of P. glabratum were investigated. The influence of seasonality on its chemical composition was also evaluated. The chemical characterization was performed by two-dimensional gas chromatography coupled with quadrupole mass spectrometry (GC×GC/qMS). Altogether, 199 compounds were identified in the EOs and their composition varied during the seasonal cycle. The main compounds found were sesquiterpenes and their oxygenated analogues. EOs showed antioxidant activity, measured by 2,2-diphenyl-1-picrylhydrazyl-DPPH (from 28.1 to 33.4 µg mL-1) and β-carotene assays (from 57.4 to 66.4%), and inhibitory action against C. albicans. The oils provided expressive properties; however, the yield of EO from winter was not enough for activities assays, remarking the influence of the seasonality on the biological activities of this plant.