Collection and identification of an unknown component from Eugenia uniflora essential oil exploiting a multidimensional preparative three-GC system employing apolar, mid-polar and ionic liquid stationary phases. (23rd May 2019)

• Record Type: Journal Article
• Authors: Sciarrone, Danilo; Schepis, Antonino; De Grazia, Gemma; Rotondo, Archimede; Alibrando, Filippo; Cipriano, Roger Raupp; Bizzo, Humberto; Deschamps, Cicero; Sidisky, Leonard M.; Mondello, Luigi
• Is Part Of: Faraday discussions. Volume 218(2019)
• Page Start: 101
• Page End: 114
• Publication Date: 2019-05-23
• Subjects: Chemistry -- Periodicals; Metallurgy -- Periodicals; Electrochemistry -- Periodicals; 540
• DOI: 10.1039/c8fd00234g
• Languages: English
• ISSNs: 1359-6640

Abstract

Abstract : MDGC-Prep is used in combination with NMR, GC-FTIR and GC-MS analyses for the structure elucidation of an unknown component from Eugenia uniflora L. essential oil. Abstract : The present research deals with the collection and structural elucidation of an unknown component, accounting for about 35% of the essential oil obtained upon distillation of the leaves of Eugenia uniflora L., harvested during summer (January, 2017) in Paraná State (Southern Brazil). A multidimensional gas chromatographic preparative system, based on the coupling of three GC systems equipped with apolar, PEG and ionic liquid-based stationary phases, was successfully applied for the isolation of the chromatographic band relative to the unknown molecule. The use of wide-bore columns allowed for an increased sample capacity compared to conventional micro-bore columns, thus the injection of a neat sample was feasible, greatly reducing the total collection time. A higher chromatographic efficiency was afforded by the use of a multidimensional approach in the heart-cut mode, exploiting the different selectivity of three stationary phases, which ensured the attainment of a highly pure fraction. In only five runs, more than 3 milligrams were collected, with an average purity greater then 95%. Finally, the unknown component was subjected to nuclear magnetic resonance spectroscopy, mass spectrometry and condensed phase Fourier-transform infrared spectroscopy, leading to the identification of 6-ethenyl-6-methyl-3, 5-di(prop-1-en-2-yl)cyclohex-2-en-1-one. The presented approach has been demonstrated to be effective for the isolation and structural elucidation of unknown molecules in complex samples, which will allow for further in-depth studies, like biological evaluation or pharmacological tests.