Curcuma species have been cultivated in tropical and subtropical regions in Asia, Australia, and South America for culinary as well as medicinal applications. The biological activities of Curcuma have been attributed to the non-volatile curcuminoids as well as to volatile terpenoids. Curcuma essential oils have demonstrated a wide variety of pharmacological properties. The objective of this work was to examine the variation in the compositions of Curcuma rhizome essential oils. In this work, the volatile oils from C. longa and C. zedoaria were obtained and analyzed by gas chromatography-mass spectrometry. The chemical compositions of C. longa and C. zedoaria essential oils, including those reported in the literature, were analyzed by hierarchical cluster analysis. In addition, cluster analyses of the chemical compositions of C. aromatica and C. aeruginosa from the literature were also carried out. Curcuma longa volatiles were dominated by α-turmerone, curlone, ar-turmerone, β-sesquiphellandrene, α-zingiberene, germacrone, terpinolene, ar-curcumene, and α-phellandrene and showed four distinct chemical clusters. C. zedoaria rhizome oil contained 1,8-cineole, curzerenone/epi-curzerenone, α-copaene, camphor, β-caryophyllene, elemol, germacrone, curzerene, and β-elemene and showed two different chemical types. C. aromatica had three clearly defined clusters, and C. aeruginosa had three types.
Keywords: Curcuma aeruginosa; Curcuma aromatica; Curcuma longa; Curcuma zedoaria; rhizome essential oils.