Screening of chemical composition, anti-arthritis, antitumor and antioxidant capacities of essential oils from four Zingiberaceae herbs

Because of massive applications of Zingiberaceae herbs in cosmetics, health care products and medicines, essential oils from herbs have also attracted more and more attention. In this study, chemical compositions and bioactivities of four genuine Zingiberaceae herbs essential oils from Alpinia oxyphylla Miq. (AOEOs), Kaempferia galanga L. (KGEOs), Amomum kravanh Pierre ex Gagnep.(AKEOs), and Alpinia galanga (Linn.) Willd (AGEOs) are evaluated. More than 45 components have been identified from four essential oils, and cineole (0.21-58.35 %), ethyl cinnamate (1.28-29.4 %), beta-pinene (1.14-16.98 %), alpha-terpineol (0.16-13.89 %), alpha-pinene (0.03-11.42 %), p-cymene (4.11-6.93 %), and alpha-caryophyllene (0.04-5.46 %) are the dominants. Moreover, theses essential oils exhibit remarkable anti-inflammatory activities via markedly down-regulating the expression levels of cyclooxygenase-2 (COX-2), tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), and interleukin-1 (IL-1) in adjuvant arthritis rats. Especially, KGEOs have the most excellent anti-inflammatory activities. Furthermore, four essential oils also reveal marked cytotoxicity against LNCaP cells (IC50, 18.42-113.76 mu g/mL) and B16 cells (IC50, 54.11-101.31 mu g/mL), and KGEOs possess the greatest cytotoxic activity. Additionally, four essential oils display comparable antioxidant activities from its half maximal inhibitory concentration (IC50, 7.93-13.83 mu g/mL) to Trolox C (IC50, 13.27 mu g/mL) according to 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging ability, and KGEOs (IC50, 7.93 mu g/mL) are the optimum candidate for antioxidant. Therefore, these results have indicated that the four Zingiberaceae herbs essential oils have outstanding but different bioactivities, making them ideal additives for natural functional nutrition and medicine like for antitumor, antioxidant and antiarthritic drugs.