title: Volatile compounds of Viola odorata absolutes: identification of odorant active markers to distinguish plants originating from France and Egypt.
abstract: Absolutes isolated from Viola odorata leaves, valuable materials for the flavor and fragrance industry, were studied. Violets are mainly cultivated in France and Egypt and extracted locally. The absolutes of the two origins showed different olfactory profiles both in top and heart notes, as evidenced by sensory analysis. The aims of this study were i) to characterize the volatile compounds, ii) to determine the odorant-active ones, and iii) to identify some markers of the plant origin. Two complementary analytical methods were used for these purposes, i.e., headspace solid-phase microextraction (HS-SPME) using different fiber coatings followed by GC/MS analysis and gas chromatography - olfactometry/mass spectrometry (GC-O/MS) applied to violet leaf extracts. From a total of 70 identified compounds, 61 have never been reported so far for this species, 17 compounds were characterized by both techniques (with seven among them known from the literature), 23 compounds were solely identified by HS-SPME GC/MS (among them only two being already mentioned as components of violet absolutes in the literature), and, finally, 30 compounds were only identified by GC-O/MS. According to the HS-SPME GC/MS analyses, ethyl hexanoate and (2E,6Z)-nona-2,6-dienol were specific volatile compounds of the sample with French origin, while (E,E)-hepta-2,4-dienal, hexanoic acid, limonene, tridecane, and eugenol were specific of the samples with Egyptian origin. Additional compounds that were not detected by HS-SPME GC/MS analysis were revealed by GC-O analyses, some of them being markers of origin. Pent-1-en-3-ol, 3-methylbut-2-enal, 2-methoxy-3-(1-methylethyl)pyrazine, 4-ethylbenzaldehyde, β-phenethyl formate, and 2-methoxy-3-(2-methylpropyl)pyrazine revealed to be odorant markers of the French sample, whereas cis-rose oxide, trans-rose oxide, and 3,5,5-trimethylcyclohex-2-enone were odorant markers of the Egyptian samples.
authors.affiliation: Institut de Chimie de Nice, Université Nice Sophia-Antipolis, UMR CNRS 7272, Parc Valrose, F-06108 Nice Cedex 2 (phone: +33-492076469; fax: +33-492076125); PAYAN BERTRAND, 28, Av. Jean XXIII, F-06130 Grasse; European Research Institute on Natural Ingredients (ERINI), Espace Jacques-Louis Lions, 4 Traverse Dupont, F-06130 Grasse.
authors.forename: Laure
authors.initials: L
authors.lastname: Saint-Lary
authors.forename: Céline
authors.initials: C
authors.lastname: Roy
authors.forename: Jean-Philippe
authors.initials: JP
authors.lastname: Paris
authors.forename: Pascal
authors.initials: P
authors.lastname: Tournayre
authors.forename: Jean-Louis
authors.initials: JL
authors.lastname: Berdagué
authors.forename: Olivier P
authors.initials: OP
authors.lastname: Thomas
authors.forename: Xavier
authors.initials: X
authors.lastname: Fernandez
mesh_terms: D004534:Egypt; D005602:France; D009812:Odorants; D018515:Plant Leaves / Q000737:chemistry*; D032413:Viola / Q000737:chemistry*; D055549:Volatile Organic Compounds / Q000737:chemistry* / Q000302:isolation & purification
chemical_list: D055549:Volatile Organic Compounds
keywords: Gas chromatography - olfactometry (GC-O); Headspace solid-phase microextraction (HS-SPME); Leaf absolutes; Sensory analysis; Viola odorata