Enantiomeric Ratio Changes of Terpenes in Essential Oils from Hybrid Eucalyptus grandis × E. tereticornis and its Pure Species

Abstract

Some Eucalyptus species produce oils with biological activities and the effect of their interspecific hybridization on the enantiomeric composition of terpenes has not been reported. The enantiomeric excesses of monoterpenes in the essential oil of Eucalyptus grandis × E. tereticornis and its parental taxa were determined by gas chromatography-mass spectrometry (GC-MS), and to resolve coelutions problems by preparative high performance liquid chromatography (HPLC) and GC-MS with two columns in series. The essential oil composition of the hybrid presented qualitative and quantitative differences with the composition of its parental taxa. Great differences were found for the enantiomeric ratio in monoterpene alcohols among the three essential oils. Our results suggest that the enantiomeric analysis can be a reliable method for the study of how the interspecific hybridization can module the enantiomeric chemical profile in Eucalyptus essential oils. These results suggest the use of interspecific hybridization to improve or expand the source of bioactive compounds.

Practical method for increasing optical purity of cis‐verbenol

“…The co‐occurrence of (+) and (−) forms is fairly common among the cyclic monoterpenes . Especially, for pinene, and its metabolites, optical activity varies over a wide range, and the natural compound may be both dextrorotatory and levorotatory depending on the source its origin . The same goes for the commercially available semisynthetic verbenone and cis ‐verbenol which are usually marketed with a relatively low enantiomeric excess .…”