title: α-Linalool - a marker compound of forged/synthetic sweet basil (Ocimum basilicum L.) essential oils.
abstract: BACKGROUND
  Ocimum basilicum L. (sweet basil) is known to occur as several chemotypes or cultivars that differ in their essential oil composition. The surprising discovery of 3,7-dimethylocta-1,7-dien-3-ol, the rare α isomer of the well-known monoterpene alcohol β-linalool (3,7-dimethylocta-1,6-dien-3-ol), in samples of Serbian basil oil provoked an investigation of the origin of α-linalool in these samples. Three scenarios were considered, namely (a) the existence of a new natural chemotype, (b) an artefactual formation during the isolation procedure and (c) the case of a synthetic/forged oil.
  
  
  RESULTS
  Noteworthy amounts (15.1-16.9%) of pure α-linalool were isolated from a commercial sample of basil oil, and detailed spectral analyses (MS, IR, (1) H and (13) C NMR) unequivocally confirmed its identity. The analysis by GC and GC/MS of an additional 20 samples of different O. basilicum oils commercially available on the Serbian market or isolated from plant material cultivated in Serbia resulted in the identification of 149 compounds. The obtained compositional data were compared using multivariate statistical analysis to reveal the possible existence of a new basil chemotype.
  
  
  CONCLUSIONS
  The results of the chemical and statistical analyses give more pro arguments for the synthetic/forged oil hypothesis and suggest that α-linalool could be used as a marker compound of such O. basilicum oils.
authors.affiliation: Department of Chemistry, Faculty of Science and Mathematics, University of Niš, Višegradska 33, 18000, Niš, Serbia.
authors.forename: Niko S
authors.initials: NS
authors.lastname: Radulović
authors.forename: Polina D
authors.initials: PD
authors.lastname: Blagojević
authors.forename: Ana B
authors.initials: AB
authors.lastname: Miltojević
mesh_terms: D000080462:Acyclic Monoterpenes; D015415:Biomarkers / Q000032:analysis*; D002849:Chromatography, Gas; D008401:Gas Chromatography-Mass Spectrometry; D039821:Monoterpenes / Q000032:analysis* / Q000302:isolation & purification; D031339:Ocimum; D018649:Ocimum basilicum / Q000737:chemistry*; D009822:Oils, Volatile / Q000737:chemistry*; D010938:Plant Oils / Q000737:chemistry; D055771:Serbia
chemical_list: D000080462:Acyclic Monoterpenes; D015415:Biomarkers; D039821:Monoterpenes; D009822:Oils, Volatile; D010938:Plant Oils; C018584:linalool; C051168:basil oil
keywords: Lamiaceae; Ocimum basilicum L; forged/synthetic oil; multivariate statistical analysis; sweet basil; α-linalool; β-linalool