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The essential oil of coriander leaves (Coriandrum sativum) and wild coriander leaves (Eryngium foetidum) grown in Fiji was obtained by steam distillation. The aroma profiles were characterised using gas chromatography-olfactometry (GCO) and CharmAnalysis. The character-impact odorants were identified using comprehensive two-dimensional gas chromatography (GC x GC) combined with time-of-flight mass spectrometry (TOFMS). During GCO analysis, the co-elution of E-2-alkenals and E-2-alken-1-ols resulted in the perception of 'odour-clusters'. The most important odorants in C. sativum were found to be Z-2-decenal, a co-eluting odour-cluster (E-2-dodecenal, E-2-dodecen-1-ol, and 1-dodecanol), beta-ionone, eugenol, and E-2-decenal. E-2-decen-1-ol was the most abundant compound in C. sativum (26.0% TIC) but only contributed 0.39% of the total odour activity. The most abundant compound in E. foetidum was E-2-dodecenal (63.5% TIC), which also contributed the most odour activity (52.9%). Other important odorants were either eugenol or a trimethylbenzaldehyde isomer, beta-ionone, Z-4-dodecenal, dodecanal, and E-2-tetradecenal. GC x GC-TOFMS allowed the identification of 42 and 20 compounds not previously reported in the literature for C. sativum and E. foetidum, respectively. In particular, beta-ionone was determined to be an important odorant in both samples but could not be identified with GC-qMS.

The I3C NMR spectra of eight triterpenes are recorded and all carbon shifts have been assigned. The data are in agreement with the structures assigned to the rare lupanediol, lup-20(29)-ene-3cu,23-diol, and other lupane triterpenes isolated from the Sri Lankan Glochidion species (Euphorbiaceae). The I3C NMR data of some triterpenes, aleuritolic acid derivatives and taraxerane derivatives are compared.