COMPARISON BETWEEN COLD‐PRESSED AND DISTILLED LIME OILS THROUGH THE APPLlCATlON OF GAS CHROMATOGRAPHY AND MASS SPECTROMETRY

Abstract

ABSTRACT31 volatile components representing 98.2% of the volatile fraction of Mexican cold‐pressed lime oil and 37 components representing 91.2% of the volatile constituents of distilled Mexican lime oils were identified. A total of 41 compounds were identified including 14 alcohols, 3 aldehydes, 2 esters, an aliphatic hydrocarbon, 11 monoterpenes, 8 sesquiterpenes, and 2 oxides. The unidentified components are present in trace quantities. Comparison of the GLC chromatograms of cold‐pressed and distilled Mexican and West‐Indian lime oils showed that α‐pinene, β‐pinene, myrcene and γ‐terpinene were present in lesser amounts in the distilled oil than in the cold‐pressed oil. The sesquiterpene hydrocarbons, β‐caryophellene, α‐bergamotene, α‐ and β‐humulene, and β‐bisabolene, were also found to be present in decreased quantities in the distilled oil as compared to the cold‐pressed oil. While α‐thujene, neral, geranial, decanal, geranyl acetate, neryl acetate, and α‐ and β‐elemene were present in the cold‐pressed oil, they were almost absent from the distilled oil. There was an increase in concentration of camphene, d‐limonene, terpinolene and terpinene‐4‐ol in the distilled oil. Compounds which apparently were formed during distillation were identified as α‐phellandrene, 1,4‐cineole, p‐cymene, α‐fenchyl alcohol, and α‐ and β‐terpineol. Six compounds which have not been previously reported in lime oil were identified as n‐nonane, α‐thujene, α‐phellandrene, α‐fenchyl alcohol, β‐elemene and guaiene.