THE SEARCH STRUCTURE OF TERPINEN-4-OL USING ITS FRAGMENTATION ENERGY PROFILE: CASE STUDY FOR A GC-MS ANALYSIS OF THE LAVENDER OIL

  • Lucian Copolovici Deputy Director of RDI Institute in Natural and Technical Sciences of “Aurel Vlaicu” University
  • Dumitru CONDRAT Faculty of Food Engineering, Tourism and Environmental Protection
  • Nicolae DINCA Faculty of Food Engineering, Tourism and Environmental Protection
Keywords: differential mass spectrometry, structure identification, fragmentation energy, lavender oil, terpinen-4-ol

Abstract

The automated elucidation by GC-MS of isomeric structures by using mass spectral libraries and
retention indexes databases often offers contradictory results in the case of the high similarity of the structures and the
spectra. Under these circumstances, a certification of the unknown structures by using additional orthogonal filtering of
candidate structures would increase the confidence in the analysis. For such additional filtering we propose here a
correlation algorithm between the profile of some primary ionic currents and that of corresponding fragmentation
energies obtained through quantum chemical calculation (QCC). In our paper we present the application of this algorithm
in the case of terpinen-4-ol, a biologically active compound from essential oils. The fragmentation energy profile of the
terpinen-4-ol has been identified with the maximum correlation (94.2%) among the fifteen components revealed in GCMS
analysis of lavender oil. An additional validation was done by applying the algorithm for another fourteen candidate
structures, isomeric with terpinen-4-ol. The result is consistent with the library-based assignments and chromatographic
alignment. One of the advantages of this approach is that the use of these three analytical variants can provide high
accuracy of analysis without the direct use of chemical standards.

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Published
2019-07-18