Comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry (GC × GC/TOFMS) for the analysis of volatile compounds in Piper regnellii (Miq.) C. DC. essential oils

This work combines the analytical capability of GC × GC/TOFMS, the use of retention indices and adequate software tools for the study of essential oils of Piper regnellii (Miq.) C. DC. (pariparoba) growing wild in “cerrado” landscape, Central-West region, Brazil. The leaves, stems and flowers of P. regnellii generated essential oils with 163, 119 and 110 compounds tentatively identified, respectively. The major compounds in each essential oil were approximately the same, except dill apiole, which was concentrated more highly in the stems. The major compounds were: myrcene, anethole E and bicyclogermacrene (22%, 19% and 5%, respectively) in leaves, anethole E, dill apiole and myrcene (20%, 19% and 16%, respectively) in stems and anethole E, myrcene and bicyclogermacrene (24%, 18% and 9%, respectively) in flowers. This is the first time that this plant was analyzed by GC × GC/TOFMS and this technique allows identification of a higher number of compounds when compared to traditional one-dimensional chromatography.