With 20 MTT (5 mg/ml in PBS) and incubated at 37 for 4 h. The purple-blue formazan precipitate was dissolved in 100 dimethyl sulfoxide and the optical density was measured at a wavelength of 570 nm on a 96-well plate reader (Thermo Labsystems, Franklin, MA USA). The IC50 was calculated as the concentration of compounds that achieved a 50 inhibition of cell viability. Data were analyzed using a SlideWrite program (Advanced Graphics Software, Inc., Rancho Santa Fe, CA, USA) to determine the IC50 of each drug independently. Synergistic effect analysis. Isobologram curves were derived as described previously (13): IC50 A and B = DA / IC X,AFigure 1. Isobologram and combination index curves at 50 effect level using combinations of myrrh and frankincense essential oils.+ DB / ICX,B; where IC50 A and B indicates the combination concentration of drugs A and B at 50 inhibition, ICX,A and ICX,B indicates the concentration of the drugs that result in 50 inhibition independently and DA and DB indicates the concentrations of the two drugs as a mixture to achieve 50 inhibition. The isobologram curve was generated by plotting doses of drugs A vs. B predicted to simultaneously achieve 50 cell growth inhibition. A standard line of Loewe additivity was included to indicate a lack of interaction, and points below and above the line indicated synergy and antagonism, respectively. Cell apoptosis assay. Flow cytometry was used for the quantitative measurement of apoptosis. Briefly, 1×106 MCF-7 cells were treated with 0, 10, 20 and 40 /ml frankincense and/or myrrh essential oils for 24 and 48 h, respectively. The cells were then collected by trypsinization and washed once with cold PBS. BD tubes were used and 100 suspension was added to each labeled tube followed by 10 Annexin V-FITC and 10 PI (20 /ml). Following incubation for 20 min at room temperature in the dark, 400 PBS binding buffer was added to each tube without washing.Agomelatine Within 30 min, the mixtures were analyzed using flow cytometry (BD FACSAria; BD Biosciences, San Jose, USA).ADC-Related Custom Services Results GCMS analysis.PMID:29844565 The content of the extracted oil of myrrh and frankincense was 0.41 ml (2.05 , ml/g) and 0.62ml (2.06 , ml/g), respectively, and the total ion figures of the constituents were obtained by GC-MS analysis. The area normalization method was adopted to integrate the total ion peaks and the minimum area of the comparatively small peaks was set. Using a standard mass spectrum, 76 components were identified that accounted for 87.54 of the total myrrh essential oil (Table ). In addition, 99 components were identified that accounted for 91.26 of the total frankincense essential oil (Table ). MTT antiproliferative assay. Myrrh and frankincense essential oils exhibited an inhibitory effect on the cell lines and a dosedependent inhibition effect was noted. Among the fiveONCOLOGY LETTERS 6: 1140-1146,Table I. Chemical composition of myrrh essential oil. No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 Compound Bicyclo[2.2.1]heptane, 2-(1-methylethenyl)Azulene (+)-Cycloisosativene Acetic acid, octyl ester Ylangene Copaene 5H-inden-5-one, 1,2,3,6,7,7a-hexahydro-7a-methylSeychellene Cyclohexane, 1,2-diethenyl-4-(1-methylethylidene)-, cis Biurea -bourbonene (+)-Sativen Isosativene -cubebene -elemene 7-Tetracyclo[6.2.1.0(3.8)0(3.9)]undecanol, 4,4,11,11-tetramethylAromadendrene Tricyclo[6.3.0.
