Chemical compositions, antioxidative, antimicrobial, anti-inflammatory and antitumor activities of Curcuma aromatica Salisb. essential oils

The aim of this study was to investigate the chemical components, antimicrobial, antioxidative, anti-inflammatory and antitumor activities of essential oils from Curcuma aromatica Salisb. rhizomes collected from 12 different habitats in China. The chemical composition analysis of the 12 essential oils by gas chromatography-mass spectrometer (GC-MS) led to the identification of 78 components, and the dominant compounds were 8,9-dehydro-9-formyl-cycloisolongifolene (2.66-36.83%), germacrone (4.31-16.53%), ar-tunnerone (2.52-17.69%), turmerone (2.62-18.38%), ermanthin (0.75-13.26%), beta-sesquiphyllandrene (0.33-11.32%) and ar-curcumene (0.29-10.52%). Furthermore, the 12 essential oils displayed different 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activities (IC50, 1.57-21.36 mu g/ml), and most of them were superior to Trolox C (IC50, 8.8214/ml). Their antimicrobial activities against fungus were far higher than against bacteria, and essential oils of rhizomes collected from Guangxi, Zhejiang or Sichuan showed the better activities against different microorganisms. They also exhibited antitumor activities (IC50, 30.66-259.62 mu g/ml) against melanoma cells (B16) and prostate cancer cells (LNCaP), and anti-inflammatory action by significantly down-regulating expression of tumor necrosis factor-a (TNF-alpha) and cyclo-oxygenase-2 (COX-2) in vivo. On the whole, the compositions and bioactivities of these essential oils were different from each other. Hence, it is hoped that, from these results, C. aromatica rhizomes from different habitats should be used more rationally and effectively as natural pharmaceutical, culinary and cosmetic additives in the future.