Objective: To determine the chemical composition and antioxidant potential of essential oil isolated from the leaves of Curcuma longa (turmeric). Methods: Chemical composition of the oil was analyzed using GC-MS. Antiperoxidative potential was evaluated using linoliec acid emulsion system. Free radical scavenging activity was evaluated using stable DPPH and ABTS free radicals. Results: GC-MS analyses showed that major compound present in the turmeric leaf oil is b-sesquiphellandrene (22.8%) followed by terpinolene (9.5%). Essential oil also exhibited reductive potential and antioxidant potential in linoleic acid emulsion system along with DPPH and ABTS free radical scavenging potential. Conclusions: The overall result suggests that turmeric leaf oil is capable of retarding oxidation reaction and free radical mediated damage and can be developed as a potent natural antioxidant.

OBJECTIVEDeoxyelephantopin, a sesquiterpene lactone from Elephantopus scaber, showed inhibition of the growth of various tumor cells in vitro. In the present study, we investigated the cytotoxicity and apoptosis-inducing capacity of deoxyelephantopin on lung adenocarcinoma (A549) cells.

METHODSThe cytotoxic effect of deoxyelephantopin on A549 cells and normal lymphocytes was evaluated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and 50% inhibitory concentration (IC50) value was determined. The self-renewal and proliferating potential of A549 cells after treatment with deoxyelephantopin were examined by colony formation assay. Cellular morphology of deoxyelephantopin-treated cells was observed using phase-contrast microscopy. The induction of apoptosis was evaluated using acridine orange and ethidium bromide staining, Hoechst 33342 staining, terminal deoxynucleotidyl transferase-mediated dUTP biotin nick end-labeling (TUNEL) assay, DNA fragmentation analysis and Annexin V-fluorescein isothiocyanate staining by flow cytometry. Activation of caspases was detected using fluorogenic substrate specific to caspases 2, 3, 8 and 9 and flow cytometric analysis. The total cellular DNA content and expression of cleaved poly (ADP-ribose) polymerase was also analyzed.

RESULTSDeoxyelephantopin exhibited cytotoxicity to A549 cells (IC50 = 12.287 μg/mL), however, there was no toxicity towards normal human lymphocytes. Deoxyelephantopin suppressed the colony-forming ability of A549 cells in a dose-dependent manner. Acridine orange, ethidium bromide and Hoechst 33342 staining showed cell shrinkage, chromosomal condensation and nuclear fragmentation, indicating induction of apoptosis. Deoxyelephantopin increased apoptosis of A549 cells, as evidenced by more TUNEL-positive cells. DNA fragmentation and Annexin V staining revealed late-stage apoptotic cell population. Deoxyelephantopin inhibited A549 cell growth by cell cycle arrest at G2/M phase and induced apoptosis through both extrinsic and intrinsic pathways.

CONCLUSIONThese results suggest that deoxyelephantopin has great potential as a new chemotherapeutic agent to be developed further for the treatment of lung cancer.

Adenocarcinoma ; drug therapy ; pathology ; Antineoplastic Agents, Phytogenic ; pharmacology ; Apoptosis ; drug effects ; Caspases ; physiology ; Cell Cycle ; drug effects ; Cell Line, Tumor ; Dose-Response Relationship, Drug ; Humans ; Lactones ; pharmacology ; Lung Neoplasms ; drug therapy ; pathology ; Sesquiterpenes ; pharmacology