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Chemical Composition, Antioxidant, and Antibacterial Activities of Essential Oils from Etlingera brevilabrum Valeton

Behnam Mahdavi, Wan A. Yaacob, Laily B. Din, Lee Yook Heng and Nazlina Ibrahim

School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia

Department of Chemistry, Faculty of Science, Hakim Sabzevari University, Sabzevar, Iran

School of Biosciences and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia

Abstract: Essential oils from fresh parts of Etlingera brevilabrum Valeton (Zingiberaceae) including rhizome, stolon, stem, and leaves were hydrodistilled, and studied for their chemical composition, antioxidant, and antibacterial activity. Characterization by GC-FID and GC-MS showed monoterpene hydrocarbons dominated the oils of the leaves and stems (57.3 and 73.4%) with oxygenated monoterpenes were dominant in the stolon and rhizomes (40.4 and 53.6%). The major compounds of the rhizome oil were perilla aldehyde (19.6%) and bornyl acetate (17.6%); the stolon oil, β-pinene (30.6%) and p-cymen-7-ol (25.0%); the stem oil, δ-3-carene (43.2%) and α-thujene (17.7%); and the leaf oil, α-thujene (38.1%) and p-cymen-7-ol (8.0%). The rhizome oil showed the highest antioxidant effects with IC 50 = 1236.54±12.83 µ g/mL in the DPPH radical scavenging activity, 22.76% inhibition in the β-carotene bleaching test at 1000 µ g/mL, and IC 50 = 878±16.54 µ g/mL in the ferrous ion chelating ability. Antibacterial activity demonstrated by disc diffusion assay showed that the rhizome, stem and leaf oils inhibited Staphylococcus aureus and MRSA but not Bacillus subtilis and Bacillus thuringiensis. For Gram negative bacteria, the rhizome oil prevented the growth of Proteus mirabilis ; the stem oil inhibited Escherichia coli and Proteus vulgaris ; and the leaf oil was active against E. coli , P. vulgaris , and P. mirabilis .

Keywords: Etlingera brevilabrum ; essential oils; GC-FID and GC-MS analyses ; antioxidant; antibacteria. © 2015 ACG Publications. All rights reserved. © 2015 ACG Publications. All rights reserved.