Comprehensive two-dimensional gas chromatography with mass spectrometry applied to the analysis of volatiles in artichoke (Cynara scolymus L.) leaves

Artichoke (Cynara scolymus L.) is well known due to its medicinal properties and, as a result, a large number of studies have been conducted to determine the chemical constituents produced by the plant. However, investigations were mainly focused on the non-volatile compounds, while the volatile constituents remained largely neglected. This study was aimed at obtaining a deeper understanding of the volatile composition of artichoke. For this propose, comprehensive two-dimensional gas chromatography coupled to a rapid scanning quadrupole mass spectrometer (GC x GC/qMS) and retention indices were used to improve the chemical characterization of volatiles from leaves. A total of 130 compounds were found, 109 of which are reported for the first time in C. scolymus L., including oxygenated monoterpenes, sesquiterpenes, oxygenated sesquiterpenes, norisoprenoids, lactones, alcohols, ketones and aldehydes. The major compounds were 1-octen-3-one (3.85%), (E)-2-hexenal (3.75%), benzene acetaldehyde (2.90%), 2,2-dimethyl-4-pentenal (2.81%), beta-ionone (1.94%), furfural (1.65%), (E)-beta-damescenone (1.59%), alpha-methyl-gamma-butirolactone (1.53%), benzaldehyde (1.47%) and dihydroactinidiolide (1.44%). The comprehensive GC x GC/qMS approach enabled a greater number of analytes to be identified, approximately four times higher than that obtained for GC/qMS. Additionally, the results imply that artichoke leaves are a potential source of volatile bioactive compounds. (C) 2014 Elsevier B.V. All rights reserved.