Composition of the Essential Oils and Volatile Fractions of Artemisia absinthium by Three Different Extraction Methods: Hydrodistillation, Solvent-Free Microwave Extraction and Headspace Solid-Phase Microextraction Combined with a Novel QSRR Evaluation

Abstract

The present work is mainly focused on relative abilities of three different extraction techniques, namely hydrodistillation (HD), solvent-free microwave extraction (SFME) and headspace solid-phase microextraction (HS-SPME) to separate the essential oils and volatile fractions from stems, leaves and fruits of Artemisia absinthium L., in combination with analysis by GC and GC-MS. By means of the HD method, 16, 21 and 31 components were identified in the stem, leaf and fruit oils, representing 99.9%, 98.5% and 98.0% of the total oil components, respectively; by the SFME method, 27, 23 and 20 components were identified, constituting 98.4%, 100.0% and 100.0% of the oils, respectively. The HS-SPME method revealed even more constituents, namely 37, 37 and 31 volatile fractions from the stem, leaf and fruit of A. absinthium, representing 99.5%, 98.5% and 95.4% of the total chemical profiles. β-Thujone, 1,8-cineole, cis-chrysanthenol, sabinene and α-phellandrene were identified as major compounds in all of the oils and volatiles. Furthermore, a quantitative structure-retention relationship (QSRR) study was performed using stepwise multiple linear regression (SW-MLR) method. A model, with high statistical significance (R2 = 0.952, Q2LOO =0.932, Q2LGO =0.930, F = 104.4), was found to be appropriate for predicting the retention indices of the essential oils and volatile components.