Essential Oil Composition, Cytotoxic and Antibacterial Activities of Five EtlingeraSpecies from Borneo

Essential oils obtained by hydrodistillation from the rhizomes of Etlingera pyramidosphaera(K. Schum.) R. M. Sm, E. megalocheilos(Griff.) A.D. Poulsen, comb. nov., E. coccnea(Blume) S. Sakai & Nagam, E. elatior(Jack) R. M. Sm, and E. brevilabrum(Valeton) R. M. Sm were analyzed by GCMS. The highest oil yield was obtained from E. pyramidosphaera(0.45%), followed by E. elatior(0.38%), E. coccnea(0.30%), E. brevilabrum(0.28%) and E. megalocheilos(0.25%). The major constituents of the essential oils were oxygenated monoterpenes, followed by sesquiterpenes, oxygenated sesquiterpenes, oxygenated diterpenes and diterpenes. The essential oils from E. pyramidosphaeraand E. brevilabrumexhibited the best cytotoxicity against MCF 7 (LC50: 7.5±0.5 mg mL−1) and HL 60 (LC50: 5.0 mg mL−1), respectively. Strong inhibition was also observed for the essential oils of E. coccneaand E. megalocheilosagainst Staphylococcus aureus(MIC: 8.0±0.5 mg mL−1and 5.0±0.5 mg mL−1) and Streptococcus pyrogenes(MIC: 6.0±0.5 mg mL−18.0±0.5 mg mL−1).