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Sample records for active compounds emitted

  1. Study of compounds emitted during thermo-oxidative decomposition of polyester fabrics

    Directory of Open Access Journals (Sweden)

    Dzięcioł Małgorzata

    2016-03-01

    Full Text Available Compounds emitted during thermo-oxidative decomposition of three commercial polyester fabrics for indoor outfit and decorations (upholstery, curtains were studied. The experiments were carried out in a flow tubular furnace at 600°C in an air atmosphere. During decomposition process the complex mixtures of volatile and solid compounds were emitted. The main volatile products were carbon oxides, benzene, acetaldehyde, vinyl benzoate and acetophe-none. The emitted solid compounds consisted mainly of aromatic carboxylic acids and its derivatives, among which the greatest part took terephthalic acid, monovinyl terephthalate and benzoic acid. The small amounts of polycyclic aromatic hydrocarbons were also emitted. The emission profiles of the tested polyester fabrics were similar. The presence of toxic compounds indicates the possibility of serious hazard for people during fire.

  2. Fluorescent deep-blue and hybrid white emitting devices based on a naphthalene-benzofuran compound

    KAUST Repository

    Yang, Xiaohui; Zheng, Shijun; Chae, HyunSik; Li, Sheng; Mochizuki, Amane; Jabbour, Ghassan E.

    2013-01-01

    We report the synthesis, photophysics and electrochemical properties of naphthalene-benzofuran compound 1 and its application in organic light emitting devices. Fluorescent deep-blue emitting devices employing 1 as the emitting dopant embedded in 4

  3. Application of headspace for research volatile organic compounds emitted from building materials

    Directory of Open Access Journals (Sweden)

    Kultys Beata

    2018-01-01

    Full Text Available Headspace technique and gas chromatography method with mas detector has been used for the determination of volatile organic compounds (VOC emitted from various building and finishing materials, such as sealing foams, mounting strips, paints, varnishes, floor coverings. The tests were carried out for different temperatures (in the temperature range of 60 to 180 °C and the time of heated vials with tested materials inside. These tests were conducted to verify the possibility of use this method of determination the VOC emission. Interpretation of chromatograms and mass spectra allowed to identify the type of compounds emitted from the tested materials and the optimum time and temperature for each type of material was determined. The increase in heating temperature of the samples resulted in increase the type and number of identified compounds: for four materials the increase was in the whole temperature range, for others it was from 90 °C. On the other hand, emission from mineral wool was low in whole temperature range. 30-minutes heating of the samples was sufficient to identify emitted compounds for most of tested materials. Applying a longer time, i.e. 24 hours, significantly increased the sensitivity of the method.

  4. Advanced Characterization of Semivolatile Organic Compounds Emitted from Biomass Burning

    Science.gov (United States)

    Hatch, L. E.; Liu, Y.; Rivas-Ubach, A.; Shaw, J. B.; Lipton, M. S.; Barsanti, K. C.

    2017-12-01

    Biomass burning (BB) emits large amounts of non-methane organic gases (NMOGs) and primary (directly emitted) particulate matter (PM). NMOGs also react in plume to form secondary PM (i.e., SOA) and ozone. BB-PM has been difficult to represent accurately in models used for chemistry and climate predictions, including for air quality and fire management purposes. Much recent research supports that many previously unconsidered SOA precursors exist, including oxidation of semivolatile compounds (SVOCs). Although many recent studies have characterized relatively volatile BB-derived NMOGs and relatively non-volatile particle-phase organic species, comparatively few studies have performed detailed characterization of SVOCs emitted from BB. Here we present efforts to expand the volatility and compositional ranges of compounds measured in BB smoke. In this work, samples of SVOCs in gas and particle phases were collected from 18 fires representing a range of fuel types during the 2016 FIREX fire laboratory campaign; samples were analyzed by two-dimensional gas chromatography with time-of-flight mass spectrometry (GCxGC-TOFMS) and Fourier-transform ion cyclotron resonance mass spectrometry (FTICR-MS). Hundreds of compounds were detectable in both gas and particle phases by GCxGC-TOFMS whereas thousands of peaks were present in the FTICR mass spectra. Data from both approaches highlight that chemical fingerprints of smoke are fuel/burn-dependent. These efforts support our continued research in building the understanding and model representation of BB emissions and BB-derived SOA.

  5. Development of sampling method and chromatographic analysis of volatile organic compounds emitted from human skin.

    Science.gov (United States)

    Grabowska-Polanowska, Beata; Miarka, Przemysław; Skowron, Monika; Sułowicz, Joanna; Wojtyna, Katarzyna; Moskal, Karolina; Śliwka, Ireneusz

    2017-10-01

    The studies on volatile organic compounds emitted from skin are an interest for chemists, biologists and physicians due to their role in development of different scientific areas, including medical diagnostics, forensic medicine and the perfume design. This paper presents a proposal of two sampling methods applied to skin odor collection: the first one uses a bag of cellulose film, the second one, using cellulose sachets filled with active carbon. Volatile organic compounds were adsorbed on carbon sorbent, removed via thermal desorption and analyzed using gas chromatograph with mass spectrometer. The first sampling method allowed identification of more compounds (52) comparing to the second one (30). Quantitative analyses for acetone, butanal, pentanal and hexanal were done. The skin odor sampling method using a bag of cellulose film, allowed the identification of many more compounds when compared with the method using a sachet filled with active carbon.

  6. The average angular distribution of emitted particles in multi-step compound processes

    International Nuclear Information System (INIS)

    Bonetti, R.; Carlson, B.V.; Hussein, M.S.; Toledo, A.S. de

    1983-05-01

    A simple model for the differential cross-section that describes the angular distribution of emitted particles in heavy-ion induced multi-step compound reactions, is constructed. It is suggested that through a careful analysis of the deviations of the experimental data from the pure Hauser-Feshbach behaviour may shed light on the physical nature of the pre-compound, heavy-ion configuration. (Author) [pt

  7. Fluorescent deep-blue and hybrid white emitting devices based on a naphthalene-benzofuran compound

    KAUST Repository

    Yang, Xiaohui

    2013-08-01

    We report the synthesis, photophysics and electrochemical properties of naphthalene-benzofuran compound 1 and its application in organic light emitting devices. Fluorescent deep-blue emitting devices employing 1 as the emitting dopant embedded in 4-4′-bis(9-carbazolyl)-2,2′-biphenyl (CBP) host show the peak external quantum efficiency of 4.5% and Commission Internationale d\\'Énclairage (CIE) coordinates of (0.15, 0.07). Hybrid white devices using fluorescent blue emitting layer with 1 and a phosphorescent orange emitting layer based on an iridium-complex show the peak external quantum efficiency above 10% and CIE coordinates of (0.31, 0.37). © 2013 Published by Elsevier B.V.

  8. Biological relevance of volatile organic compounds emitted during the pathogenic interactions between apple plants and Erwinia amylovora.

    Science.gov (United States)

    Cellini, Antonio; Buriani, Giampaolo; Rocchi, Lorenzo; Rondelli, Elena; Savioli, Stefano; Rodriguez Estrada, Maria T; Cristescu, Simona M; Costa, Guglielmo; Spinelli, Francesco

    2018-01-01

    Volatile organic compounds emitted during the infection of apple (Malus pumila var. domestica) plants by Erwinia amylovora or Pseudomonas syringae pv. syringae were studied by gas chromatography-mass spectrometry and proton transfer reaction-mass spectrometry, and used to treat uninfected plants. Infected plants showed a disease-specific emission of volatile organic compounds, including several bio-active compounds, such as hexenal isomers and 2,3-butanediol. Leaf growth promotion and a higher resistance to the pathogen, expressed as a lower bacterial growth and migration in plant tissues, were detected in plants exposed to volatile compounds from E. amylovora-infected plants. Transcriptional analysis revealed the activation of salicylic acid synthesis and signal transduction in healthy plants exposed to volatiles produced by E. amylovora-infected neighbour plants. In contrast, in the same plants, salicylic acid-dependent responses were repressed after infection, whereas oxylipin metabolism was activated. These results clarify some metabolic and ecological aspects of the pathogenic adaptation of E. amylovora to its host. © 2016 BSPP AND JOHN WILEY & SONS LTD.

  9. Real-time and online screening method for materials emitting volatile organic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Changhyuk [University of Minnesota, Department of Mechanical Engineering (United States); Sul, Yong Tae [Hoseo University (Korea, Republic of); Pui, David Y. H., E-mail: dyhpui@umn.edu [University of Minnesota, Department of Mechanical Engineering (United States)

    2016-09-15

    In the semiconductor industry, volatile organic compounds (VOCs) in the cleanroom air work as airborne molecular contamination, which reduce the production yield of semiconductor chips by forming nanoparticles and haze on silicon wafers and photomasks under ultraviolet irradiation during photolithography processes. Even though VOCs in outdoor air are removed by gas filters, VOCs can be emitted from many kinds of materials used in cleanrooms, such as organic solvents and construction materials (e.g., adhesives, flame retardants and sealants), threatening the production of semiconductors. Therefore, finding new replacements that emit lower VOCs is now essential in the semiconductor industry. In this study, we developed a real-time and online method to screen materials for developing the replacements by converting VOCs into nanoparticles under soft X-ray irradiation. This screening method was applied to measure VOCs emitted from different kinds of organic solvents and adhesives. Our results showed good repeatability and high sensitivity for VOCs, which come from aromatic compounds, some alcohols and all tested adhesives (Super glue and cleanroom-use adhesives). In addition, the overall trend of measured VOCs from cleanroom-use adhesives was well matched with those measured by a commercial thermal desorption–gas chromatography–mass spectrometry, which is a widely used off-line method for analyzing VOCs. Based on the results, this screening method can help accelerate the developing process for reducing VOCs in cleanrooms.

  10. Compositions of volatile organic compounds emitted from melted virgin and waste plastic pellets.

    Science.gov (United States)

    Yamashita, Kyoko; Yamamoto, Naomichi; Mizukoshi, Atsushi; Noguchi, Miyuki; Ni, Yueyong; Yanagisawa, Yukio

    2009-03-01

    To characterize potential air pollution issues related to recycling facilities of waste plastics, volatile organic compounds (VOCs) emitted from melted virgin and waste plastics pellets were analyzed. In this study, laboratory experiments were performed to melt virgin and waste plastic pellets under various temperatures (150, 200, and 250 degrees C) and atmospheres (air and nitrogen [N2]). In the study presented here, low-density polyethylene (LDPE), polypropylene (PP), polystyrene (PS) and the recycled waste plastic pellets were used. The VOCs generated from each plastic pellets were collected by Tenax/Carboxen adsorbent tubes and analyzed by thermal desorption-gas chromatography/mass spectrometry (TD-GC/MS). The result showed the higher temperatures generated larger amounts of total VOCs (TVOCs). The VOCs emitted from the virgin plastic pellets likely originated from polymer degradation. Smaller TVOC emissions were observed in N2 atmosphere than in air atmosphere. In particular, larger amounts of the oxygenated compounds, which are generally hazardous and malodorous, were detected in air than in N2. In addition to the compounds originating from polymer degradation, the compounds originating from the plastic additives were also detected from LDPE and PS. Furthermore, various species of VOCs likely originating from contaminant inseparate polyvinyl chloride (PVC), food residues, cleaning agents, degreasers, and so on were detected from the waste plastic. Thus, melting waste plastics, as is conducted in recycling facilities, might generate larger amounts of potentially toxic compounds than producing virgin plastics.

  11. Efficient fluorescent deep-blue and hybrid white emitting devices based on carbazole/benzimidazole compound

    KAUST Repository

    Yang, Xiaohui; Zheng, Shijun; Bottger, Rebecca; Chae, HyunSik; Tanaka, Takeshi; Li, Sheng; Mochizuki, Amane; Jabbour, Ghassan E.

    2011-01-01

    We report the synthesis, photophysics, and electrochemical characterization of carbazole/benzimidazole-based compound (Cz-2pbb) and efficient fluorescent deep-blue light emitting devices based on Cz-2pbb with the peak external quantum efficiency

  12. Efficient fluorescent deep-blue and hybrid white emitting devices based on carbazole/benzimidazole compound

    KAUST Repository

    Yang, Xiaohui

    2011-07-28

    We report the synthesis, photophysics, and electrochemical characterization of carbazole/benzimidazole-based compound (Cz-2pbb) and efficient fluorescent deep-blue light emitting devices based on Cz-2pbb with the peak external quantum efficiency of 4.1% and Commission Internationale dÉnclairage coordinates of (0.16, 0.05). Efficient deep-blue emission as well as high triplet state energy of Cz-2pbb enables fabrication of hybrid white organic light emitting diodes with a single emissive layer. Hybrid white emitting devices based on Cz-2pbb show the peak external quantum efficiency exceeding 10% and power efficiency of 14.8 lm/W at a luminance of 500 cd/m2. © 2011 American Chemical Society.

  13. Emission index for evaluation of volatile organic compounds emitted from tomato plants in greenhouses

    NARCIS (Netherlands)

    Takayama, K.; Jansen, R.M.C.; Henten, van E.J.; Verstappen, F.W.A.; Bouwmeester, H.J.; Nishina, H.

    2012-01-01

    Measurement of volatile organic compounds (VOCs) emitted by plants allows us to monitor plant health status without touching the plant. To bring this technique a step further towards a practical plant diagnosis technique for greenhouse crop production, we have defined a numerical index named

  14. Detection of Volatile Compounds Emitted from Nasal Secretions and Serum: Towards Non-Invasive Identification of Diseased Cattle Biomarkers

    Directory of Open Access Journals (Sweden)

    Devin L. Maurer

    2018-03-01

    Full Text Available Non-invasive diagnostics and finding biomarkers of disease in humans have been a very active research area. Some of the analytical technologies used for finding biomarkers of human disease are finding their use in livestock. Non-invasive sample collection from diseased cattle using breath and headspace of fecal samples have been reported. In this work, we explore the use of volatile organic compounds (VOCs emitted from bovine nasal secretions and serum for finding biomarkers for bovine respiratory disease (BRD. One hundred nasal swabs and 100 serum samples (n = 50 for both ‘sick’ and ‘healthy’ were collected at the time of treatment for suspected BRD. Solid-phase microextraction (SPME was used to collect headspace samples that were analyzed using gas chromatography-mass spectrometry (GC-MS. It was possible to separate sick cattle using non-invasive analyses of nasal swabs and also serum samples by analyzing and comparing volatiles emitted from each group of samples. Four volatile compounds were found to be statistically significantly different between ‘sick’ and ‘normal’ cattle nasal swabs samples. Five volatile compounds were found to be significantly different between ‘sick’ and ‘normal’ cattle serum samples, with phenol being the common marker. Future studies are warranted to improve the extraction efficiency targeting VOCs preliminarily identified in this study. These findings bring us closer to the long-term goal of real-time, animal-side detection and separation of sick cattle.

  15. Synthesis and Electroluminescent Property of New Orange Iridium Compounds for Flexible White Organic Light Emitting Diodes.

    Science.gov (United States)

    Lee, Ho Won; Jeong, Hyunjin; Kim, Young Kwan; Ha, Yunkyoung

    2015-10-01

    Recently, white organic light-emitting diodes (OLEDs) have aroused considerable attention because they have the potential of next-generation flexible displays and white illuminated applications. White OLED applications are particularly heading to the industry but they have still many problems both materials and manufacturing. Therefore, we proposed that the new iridium compounds of orange emitters could be demonstrated and also applied to flexible white OLEDs for verification of potential. First, we demonstrated the chemical properties of new orange iridium compounds. Secondly, conventional two kinds of white phosphorescent OLEDs were fabricated by following devices; indium-tin oxide coated glass substrate/4,4'-bis[N-(napthyl)-N-phenylamino]biphenyl/N,N'-dicarbazolyl-3,5-benzene doped with blue and new iridium compounds for orange emitting 8 wt%/1,3,5-tris[N-phenylbenzimidazole-2-yl]benzene/lithium quinolate/aluminum. In addition, we fabricated white OLEDs using these emitters to verify the potential on flexible substrate. Therefore, this work could be proposed that white light applications can be applied and could be extended to additional research on flexible applications.

  16. PTR-MS analysis of reference and plant-emitted volatile organic compounds

    Science.gov (United States)

    Maleknia, Simin D.; Bell, Tina L.; Adams, Mark A.

    2007-05-01

    Proton transfer reaction-mass spectrometry (PTR-MS) was applied to the analysis of a series of volatile organic compounds (VOCs) that emit from various plants. These include a group of alcohols (methanol, ethanol and butanol), carbonyl-containing compounds (acetic acid, acetone and benzaldehyde), isoprene, acetonitrile, tetrahydrofuran (THF), pyrazine, toluene and xylene and a series of terpenes (p-cymene, camphene, 2-carene, limonene, [beta]-myrcene, [alpha]-pinene, [beta]-pinene, [gamma]-tepinene and terpinolene) and oxygen-containing terpenes (1,8-cineole and linalool). These mass spectral data were compared to an electron ionization (EI) database identifying that not all PTR-MS fragments were common to EI. PTR-MS studies of these reference compounds were utilized to identify VOCs emitted from Eucalyptus grandis leaf at a temperature range of 30-100 °C. In addition to protonated molecules (M + H)+, abundant proton-bound dimers or trimers were detected for alcohols, acetone, acetonitrile and THF. Abundant fragment ions attributed to the loss of water from these proton-bound clusters were also observed. The stability of butyl (C4H9+ m/z 57) and acetyl (CH3CO+ m/z 43) fragment ions directed the proton-transfer reactions of butanol and acetic acid. Abundant (M + H)+ ions were detected for pyrazine, THF, toluene and xylene, as well as for all terpenes except those containing oxygen. For linalool and 1,8-cineole, the loss of water generated an abundant fragment ion at m/z 137. PTR-MS fragmentation patterns for terpenes were proposed for m/z 81 (C6H9+), 93 (C7H9+), 95 (C7H11+), 107 (C8H11+), 109 (C8H13+), 119 (C9H11+), 121 (C9H13+) and 137 (loss of water for oxygen-containing terpenes; C10H17+). The relative abundances of (M + H)+ and fragments for all terpenes (except linalool) were dependent on the drift tube voltage and the optimum voltage for detection of molecular ions was different for various terpenes.

  17. Measuring volatile organic compounds and stable isotopes emitted from trees and soils of the Biosphere 2 Rainforest

    Science.gov (United States)

    Meraz, J. C.; Meredith, L. K.; Van Haren, J. L. M.; Volkmann, T. H. M.

    2017-12-01

    Rainforest trees and soils play an important role in volatile organic compound (VOC) emissions. It is known that many rainforest tree species emit these organic compounds, such as terpenes, which can have an impact on the atmosphere and can be indicative of their metabolic functions. Some VOCs also absorb infrared radiation at wavelengths at which water isotopes are measured with laser spectrometers. Normal concentrations are not high enough for ambient sampling, but increased concentrations resulting from soil and plant samples extracted using equilibrium methods affect observed isotope ratios. There is thus a need to characterize volatile emissions from soil and plant samples, and to develop better methods to account for VOC interference during water isotope measurements. In this study, we collected soil and leaf samples from plants of the Biosphere 2 Rainforest Biome, a mesocosm system created to stimulate natural tropical rainforest habitats . Volatile concentrations were measured using a Gasmet DX4015 FTIR analyzer and a custom sampling system with sulfur hexafluoride (SF6) used as a tracer gas to test for leakage, and a commercial laser spectrometer was used for isotopic analysis. We determined that the different types of tree species emit different kinds of VOCs, such as isoprenes, alcohols, and aldehydes, that will potentially have to be accounted for. This study will help build the understanding of which organic compounds are emitted and develop new methods to test for water isotopes and gas fluxes in clear and precise measures. Such measures can help characterize the functioning of environmental systems such as the Biosphere 2 Rainforest Biome.

  18. III-V group compound semiconductor light-emitting element having a doped tantalum barrier layer

    International Nuclear Information System (INIS)

    Oanna, Y.; Ozawa, N.; Yamashita, M.; Yasuda, N.

    1984-01-01

    Disclosed is a III-V Group compound semiconductor light-emitting element having a III-V Group compound semiconductor body with a p-n junction and including a p-type layer involved in forming the p-n junction; and a multi-layer electrode mounted on the p-type layer of the semiconductor body. The electrode comprises a first layer of gold alloy containing a small amount of beryllium or zinc and formed in direct contact with the p-type layer of the semiconductor body and an uppermost layer formed of gold or aluminum. A tantalum layer doped with carbon, nitrogen and/or oxygen is formed between the first layer and the uppermost layer by means of vacuum vapor deposition

  19. The impact of the fuel chemical composition on volatile organic compounds emitted by an in-service aircraft gas turbine engine

    Science.gov (United States)

    Setyan, A.; Kuo, Y. Y.; Brem, B.; Durdina, L.; Gerecke, A. C.; Heeb, N. V.; Haag, R.; Wang, J.

    2017-12-01

    Aircraft emissions received increased attention recently because of the steady growth of aviation transport in the last decades. Aircraft engines substantially contribute to emissions of particulate matter and gaseous pollutants in the upper and lower troposphere. Among all the pollutants emitted by aircrafts, volatile organic compounds (VOCs) are particularly important because they are mainly emitted at ground level, posing a serious health risk for people living or working near airports. A series of measurements was performed at the aircraft engine testing facility of SR Technics (Zürich airport, Switzerland). Exhausts from an in-service turbofan engine were sampled at the engine exit plane by a multi-point sampling probe. A wide range of instruments was connected to the common sampling line to determine physico-chemical characteristics of non-volatile particulate matter and gaseous pollutants. Conventional Jet A-1 fuel was used as the base fuel, and measurements were performed with the base fuel doped with two different mixtures of aromatic compounds (Solvesso 150 and naphthalene-depleted Solvesso 150) and an alternative fuel (hydro-processed esters and fatty acids [HEFA] jet fuel). During this presentation, we will show results obtained for VOCs. These compounds were sampled with 3 different adsorbing cartridges, and analyzed by thermal desorption gas chromatography/mass spectrometry (TD-GC/MS, for Tenax TA and Carboxen 569) and by ultra-performance liquid chromatography/ mass spectrometry (UPLC/MS, for DNPH). The total VOC concentration was also measured with a flame ionization detector (FID). In addition, fuel samples were also analyzed by GC/MS, and their chemical compositions were compared to the VOCs emitted via engine exhaust. Total VOCs concentrations were highest at ground idle (>200 ppm C at 4-7% thrust), and substantially lower at high thrust (engine were mainly constituted of alkanes, oxygenated compounds, and aromatics. More than 50 % of the

  20. Analysis of Relative Concentration of Ethanol and Other Odorous Compounds (OCs) Emitted from the Working Surface at a Landfill in China

    Science.gov (United States)

    Li, Dong; Lu, Wenjing; Liu, Yanjun; Guo, Hanwen; Xu, Sai; Ming, Zhongyuan; Wang, Hongtao

    2015-01-01

    Estimating odor emissions from landfill sites is a complicated task because of the various chemical and biological species that exist in landfill gases. In this study, the relative concentration of ethanol and other odorous compounds emitted from the working surface at a landfill in China was analyzed. Gas sampling was conducted at the landfill on a number of selected days from March 2012 to March 2014, which represented different periods throughout the two years. A total of 41, 59, 66, 54, 63, 54, 41, and 42 species of odorous compounds were identified and quantified in eight sampling activities, respectively; a number of 86 species of odorous compounds were identified and quantified all together in the study. The measured odorous compounds were classified into six different categories (Oxygenated compounds, Halogenated compounds, Terpenes, Sulfur compounds, Aromatics, and Hydrocarbons). The total average concentrations of the oxygenated compounds, sulfur compounds, aromatics, halogenated compounds, hydrocarbons, and terpenes were 2.450 mg/m3, 0.246 mg/m3, 0.203 mg/m3, 0.319 mg/m3, 0.530 mg/m3, and 0.217 mg/m3, respectively. The relative concentrations of 59 odorous compounds with respect to the concentration of ethyl alcohol (1000 ppm) were determined. The dominant contaminants that cause odor pollution around the landfill are ethyl sulfide, methyl mercaptan, acetaldehyde, and hydrogen sulfide; dimethyl disulfide and dimethyl sulfide also contribute to the pollution to a certain degree. PMID:25769100

  1. On the use of plant emitted volatile organic compounds for atmospheric chemistry simulation experiments

    Science.gov (United States)

    Kiendler-Scharr, A.; Hohaus, T.; Yu, Z.; Tillmann, R.; Kuhn, U.; Andres, S.; Kaminski, M.; Wegener, R.; Novelli, A.; Fuchs, H.; Wahner, A.

    2015-12-01

    Biogenic volatile organic compounds (BVOC) contribute to about 90% of the emitted VOC globally with isoprene being one of the most abundant BVOC (Guenther 2002). Intensive efforts in studying and understanding the impact of BVOC on atmospheric chemistry were undertaken in the recent years. However many uncertainties remain, e.g. field studies have shown that in wooded areas measured OH reactivity can often not be explained by measured BVOC and their oxidation products (e.g. Noelscher et al. 2012). This discrepancy may be explained by either a lack of understanding of BVOC sources or insufficient understanding of BVOC oxidation mechanisms. Plants emit a complex VOC mixture containing likely many compounds which have not yet been measured or identified (Goldstein and Galbally 2007). A lack of understanding BVOC sources limits bottom-up estimates of secondary products of BVOC oxidation such as SOA. Similarly, the widespread oversimplification of atmospheric chemistry in simulation experiments, using single compound or simple BVOC mixtures to study atmospheric chemistry processes limit our ability to assess air quality and climate impacts of BVOC. We will present applications of the new extension PLUS (PLant chamber Unit for Simulation) to our atmosphere simulation chamber SAPHIR. PLUS is used to produce representative BVOC mixtures from direct plant emissions. We will report on the performance and characterization of the newly developed chamber. As an exemplary application, trees typical of a Boreal forest environment were used to compare OH reactivity as directly measured by LIF to the OH reactivity calculated from BVOC measured by GC-MS and PTRMS. The comparison was performed for both, primary emissions of trees without any influence of oxidizing agents and using different oxidation schemes. For the monoterpene emitters investigated here, we show that discrepancies between measured and calculated total OH reactivity increase with increasing degree of oxidation

  2. Enhancement of electron injection in inverted bottom-emitting organic light-emitting diodes using Al/LiF compound thin film

    Science.gov (United States)

    Nie, Qu-yang; Zhang, Fang-hui

    2018-05-01

    The inverted bottom-emitting organic light-emitting devices (IBOLEDs) were prepared, with the structure of ITO/Al ( x nm)/LiF (1 nm)/Bphen (40 nm)/CBP: GIr1 (14%):R-4b (2%) (10 nm)/BCP (3 nm)/CBP:GIr1 (14%):R-4b (2%) (20 nm)/TCTA (10 nm)/NPB (40 nm)/MoO3 (40 nm)/Al (100 nm), where the thickness of electron injection layer Al ( x) are 0 nm, 2 nm, 3 nm, 4 nm and 5 nm, respectively. In this paper, the electron injection condition and luminance properties of inverted devices were investigated by changing the thickness of Al layer in Al/LiF compound thin film. It turns out that the introduction of Al layer can improve electron injection of the devices dramatically. Furthermore, the device exerts lower driving voltage and higher current efficiency when the thickness of electron injection Al layer is 3 nm. For example, the current efficiency of the device with 3-nm-thick Al layer reaches 19.75 cd·A-1 when driving voltage is 7 V, which is 1.24, 1.17 and 17.03 times larger than those of the devices with 2 nm, 4 nm and 5 nm Al layer, respectively. The device property reaches up to the level of corresponding conventional device. In addition, all inverted devices with electron injection Al layer show superior stability of color coordinate due to the adoption of co-evaporation emitting layer and BCP spacer-layer, and the color coordinate of the inverted device with 3-nm-thick Al layer only changes from (0.580 6, 0.405 6) to (0.532 8, 0.436 3) when driving voltage increases from 6 V to 10 V.

  3. Detection of the scintillation light emitted from direct-bandgap compound semiconductors by a Si avalanche photodiode at 150 mK

    International Nuclear Information System (INIS)

    Yasumune, Takashi; Takayama, Nobuyasu; Maehata, Keisuke; Ishibashi, Kenji; Umeno, Takahiro

    2008-01-01

    In this work, the direct-bandgap compound semiconductor materials are irradiated by α particles emitted from 241 Am for the detection of scintillation light at the temperature of 150 mK. For the irradiation experiment, two disk shaped samples were fabricated from an epoxy resin mixed with the powder of PbI 2 and CuI, respectively. Each disk-samples was cooled down to 150 mK by a compact liquid helium-free dilution refrigerator. A Si avalanche photodiode (APD) was employed for detecting the scintillation light emitted from the disk-sample inside the refrigerator. The detection signal current of Si APD was converted into the voltage pulses by a charge sensitive preamplifier. The voltage pulses of the scintillation light emitted from the direct-bandgap semiconductors were observed at the temperature of 150 mK. (author)

  4. The pollution characteristics of odor, volatile organochlorinated compounds and polycyclic aromatic hydrocarbons emitted from plastic waste recycling plants.

    Science.gov (United States)

    Tsai, Chung-Jung; Chen, Mei-Lien; Chang, Keng-Fu; Chang, Fu-Kuei; Mao, I-Fang

    2009-02-01

    Plastic waste treatment trends toward recycling in many countries; however, the melting process in the facilities which adopt material recycling method for treating plastic waste may emit toxicants and cause sensory annoyance. The objectives of this study were to analyze the pollution characteristics of the emissions from the plastic waste recycling plants, particularly in harmful volatile organochlorinated compounds, polycyclic aromatic hydrocarbons (PAHs), odor levels and critical odorants. Ten large recycling plants were selected for analysis of odor concentration (OC), volatile organic compounds (VOCs) and PAHs inside and outside the plants using olfactometry, gas chromatography-mass spectrometry and high performance liquid chromatography-fluorescence detector, respectively. The olfactometric results showed that the melting processes used for treating polyethylene/polypropylene (PE/PP) and polyvinyl chloride (PVC) plastic waste significantly produced malodor, and the odor levels at downwind boundaries were 100-229 OC, which all exceeded Taiwan's EPA standard of 50 OC. Toluene, ethylbenzene, 4-methyl-2-pentanone, methyl methacrylate and acrolein accounted for most odors compared to numerous VOCs. Sixteen organochlorinated compounds were measured in the ambient air emitted from the PVC plastic waste recycling plant and total concentrations were 245-553 microg m(-3); most were vinyl chloride, chloroform and trichloroethylene. Concentrations of PAHs inside the PE/PP plant were 8.97-252.16 ng m(-3), in which the maximum level were 20-fold higher than the levels detected from boundaries. Most of these recycling plants simply used filter to treat the melting fumes, and this could not efficiently eliminate the gaseous compounds and malodor. Improved exhaust air pollution control were strongly recommended in these industries.

  5. Application of HS-SPME and GC-MS to characterization of volatile compounds emitted from Osmanthus flowers.

    Science.gov (United States)

    Deng, Chunhui; Song, Guoxin; Hu, Yaoming

    2004-12-01

    Headspace solid-phase microextraction (HS-SPME) combined with gas chromatography-mass spectrometry (GC-MS) was developed for characterization of volatile compounds emitted from two varieties Osmanthus flowers of O. fragrans var. latifolius and O. fragrans var. thunbergii. The SPME parameters were studied, the optimum conditions of a 65 microm carbowax/divinylbenzene (CW/DVB), extraction temperature of 22 degrees C and extraction time of 10 min were obtained and applied to extraction of the volatile emissions. Fourteen compounds released from both varieties of Osmanthus flowers were separated and identified by GC-MS, which mainly included alpha-linalool, beta-linalool, trans-linalool oxide, cis-linalool oxide, alpha-lonone, beta-lonone, capraldehyde and decalactone. By comparing their peak areas, we found that the sums of the fourteen compounds from the two Osmanthus flowers were very close, while the relative contents of individual volatile compounds in the two emissions were very different. The relative content of alpha-linalool and beta-linalool in O. fragrans var. latifolius were 39.46% and 0.51%, while in O. fragrans var. thunbergii were 9.53% and 27.71%. Due to their different relative contents, the two varieties of flower have different fragrances.

  6. Fragranced consumer products: Chemicals emitted, ingredients unlisted

    International Nuclear Information System (INIS)

    Steinemann, Anne C.; MacGregor, Ian C.; Gordon, Sydney M.; Gallagher, Lisa G.; Davis, Amy L.; Ribeiro, Daniel S.; Wallace, Lance A.

    2011-01-01

    Fragranced consumer products are pervasive in society. Relatively little is known about the composition of these products, due to lack of prior study, complexity of formulations, and limitations and protections on ingredient disclosure in the U.S. We investigated volatile organic compounds (VOCs) emitted from 25 common fragranced consumer products-laundry products, personal care products, cleaning supplies, and air fresheners-using headspace analysis with gas chromatography/mass spectrometry (GC/MS). Our analysis found 133 different VOCs emitted from the 25 products, with an average of 17 VOCs per product. Of these 133 VOCs, 24 are classified as toxic or hazardous under U.S. federal laws, and each product emitted at least one of these compounds. For 'green' products, emissions of these compounds were not significantly different from the other products. Of all VOCs identified across the products, only 1 was listed on any product label, and only 2 were listed on any material safety data sheet (MSDS). While virtually none of the chemicals identified were listed, this nonetheless accords with U.S. regulations, which do not require disclosure of all ingredients in a consumer product, or of any ingredients in a mixture called 'fragrance.' Because the analysis focused on compounds emitted and listed, rather than exposures and effects, it makes no claims regarding possible risks from product use. Results of this study contribute to understanding emissions from common products, and their links with labeling and legislation.

  7. 40 CFR Table 34 to Subpart G of... - Fraction Measured (Fm) and Fraction Emitted (Fe) For HAP Compounds in Wastewater Streams

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Fraction Measured (Fm) and Fraction... Vessels, Transfer Operations, and Wastewater Pt. 63, Subpt. G, Table 34 Table 34 to Subpart G of Part 63—Fraction Measured (Fm) and Fraction Emitted (Fe) For HAP Compounds in Wastewater Streams Chemical name CAS...

  8. Odor impact of volatiles emitted from marijuana, cocaine, heroin and their surrogate scents

    Directory of Open Access Journals (Sweden)

    Somchai Rice

    2015-12-01

    Full Text Available Volatile compounds emitted into headspace from illicit street drugs have been identified, but until now odor impact of these compounds have not been reported. Data in support of identification of these compounds and their odor impact to human nose are presented. In addition, data is reported on odor detection thresholds for canines highlighting differences with human ODTs and needs to address gaps in knowledge. New data presented here include: (1 compound identification, (2 gas chromatography (GC column retention times, (3 mass spectral data, (4 odor descriptors from 2 databases, (5 human odor detection thresholds from 2 databases, (6 calculated odor activity values, and (7 subsequent ranking of compounds by concentration and ranking of compounds by odor impact (reported as calculated odor activity values. For further interpretation and discussion, see Rice and Koziel [1] and Rice [2].

  9. Purely Organic Thermally Activated Delayed Fluorescence Materials for Organic Light-Emitting Diodes.

    Science.gov (United States)

    Wong, Michael Y; Zysman-Colman, Eli

    2017-06-01

    The design of thermally activated delayed fluorescence (TADF) materials both as emitters and as hosts is an exploding area of research. The replacement of phosphorescent metal complexes with inexpensive organic compounds in electroluminescent (EL) devices that demonstrate comparable performance metrics is paradigm shifting, as these new materials offer the possibility of developing low-cost lighting and displays. Here, a comprehensive review of TADF materials is presented, with a focus on linking their optoelectronic behavior with the performance of the organic light-emitting diode (OLED) and related EL devices. TADF emitters are cross-compared within specific color ranges, with a focus on blue, green-yellow, orange-red, and white OLEDs. Organic small-molecule, dendrimer, polymer, and exciplex emitters are all discussed within this review, as is their use as host materials. Correlations are provided between the structure of the TADF materials and their optoelectronic properties. The success of TADF materials has ushered in the next generation of OLEDs. © 2017 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Systemic resistance induced by volatile organic compounds emitted by plant growth-promoting fungi in Arabidopsis thaliana.

    Directory of Open Access Journals (Sweden)

    Hushna Ara Naznin

    Full Text Available Volatile organic compounds (VOC were extracted and identified from plant growth-promoting fungi (PGPF, Phoma sp., Cladosporium sp. and Ampelomyces sp., using gas chromatography-mass spectrometry (GC-MS. Among the three VOC extracted, two VOC blends (emitted from Ampelomyces sp. and Cladosporium sp. significantly reduced disease severity in Arabidopsis plants against Pseudomonas syringae pv. tomato DC3000 (Pst. Subsequently, m-cresol and methyl benzoate (MeBA were identified as major active volatile compounds from Ampelomyces sp. and Cladosporium sp., respectively, and found to elicit induced systemic resistance (ISR against the pathogen. Molecular signaling for disease suppression by the VOC were investigated by treating different mutants and transgenic Arabidopsis plants impaired in salicylic acid (SA or Jasmonic acid (JA/ethylene (ET signaling pathways with m-cresol and MeBA followed by challenge inoculation with Pst. Results show that the level of protection was significantly lower when JA/ET-impaired mutants were treated with MeBA, and in SA-, and JA/ET-disrupted mutants after m-cresol treatment, indicating the involvement of these signal transduction pathways in the ISR primed by the volatiles. Analysis of defense-related genes by real-time qRT-PCR showed that both the SA-and JA-signaling pathways combine in the m-cresol signaling of ISR, whereas MeBA is mainly involved in the JA-signaling pathway with partial recruitment of SA-signals. The ET-signaling pathway was not employed in ISR by the volatiles. Therefore, this study identified two novel volatile components capable of eliciting ISR that may be promising candidates in biological control strategy to protect plants from diseases.

  11. Growth promotion of Lactuca sativa in response to volatile organic compounds emitted from diverse bacterial species.

    Science.gov (United States)

    Fincheira, Paola; Venthur, Herbert; Mutis, Ana; Parada, Maribel; Quiroz, Andrés

    2016-12-01

    Agrochemicals are currently used in horticulture to increase crop production. Nevertheless, their indiscriminate use is a relevant issue for environmental and legal aspects. Alternative tools for reducing fertilizers and synthetic phytohormones are being investigated, such as the use of volatile organic compounds (VOCs) as growth inducers. Some soil bacteria, such as Pseudomonas and Bacillus, stimulate Arabidopsis and tobacco growth by releasing VOCs, but their effects on vegetables have not been investigated. Lactuca sativa was used as model vegetable to investigate bacterial VOCs as growth inducers. We selected 10 bacteria strains, belonging to Bacillus, Staphylococcus and Serratia genera that are able to produce 3-hydroxy-2-butanone (acetoin), a compound with proven growth promoting activity. Two-day old-seedlings of L. sativa were exposed to VOCs emitted by the selected bacteria grown in different media cultures for 7 days. The results showed that the VOCs released from the bacteria elicited an increase in the number of lateral roots, dry weight, root growth and shoot length, depending on the media used. Three Bacillus strains, BCT53, BCT9 and BCT4, were selected according to its their growth inducing capacity. The BCT9 strain elicited the greatest increases in dry weight and primary root length when L. sativa seedlings were subjected to a 10-day experiment. Finally, because acetoin only stimulated root growth, we suggest that other volatiles could be responsible for the growth promotion of L. sativa. In conclusion, our results strongly suggest that bacteria volatiles can be used as growth-inducers as alternative or complementary strategies for application in horticulture species. Copyright © 2016 Elsevier GmbH. All rights reserved.

  12. Natural compounds with herbicidal activity

    Directory of Open Access Journals (Sweden)

    Mariano Fracchiolla

    2007-12-01

    Full Text Available Research about phytotoxic activity of natural compounds could lead both to find new herbicidal active ingredients and to plan environmental friendly weed control strategies. Particularly, living organisms could be a source of compounds that are impossible, for their complexity, to synthesize artificially. More over, they could have alternative sites of action respect to the known chemical herbicides and, due to their origin, they should be more environmental safe. Many living organism, such as bacteria, fungi, insects, lichens and plants, are able to produce bioactive compounds. They generally are secondary metabolites or simply waste molecules. In this paper we make a review about these compounds, highlighting potential and constraints.

  13. Natural compounds with herbicidal activity

    Directory of Open Access Journals (Sweden)

    Pasquale Montemurro

    2011-02-01

    Full Text Available Research about phytotoxic activity of natural compounds could lead both to find new herbicidal active ingredients and to plan environmental friendly weed control strategies. Particularly, living organisms could be a source of compounds that are impossible, for their complexity, to synthesize artificially. More over, they could have alternative sites of action respect to the known chemical herbicides and, due to their origin, they should be more environmental safe. Many living organism, such as bacteria, fungi, insects, lichens and plants, are able to produce bioactive compounds. They generally are secondary metabolites or simply waste molecules. In this paper we make a review about these compounds, highlighting potential and constraints.

  14. Metrological aspects of radiochemical methods for determining activity of gamma-emitting nuclides

    International Nuclear Information System (INIS)

    Shcherbakov, B.Y.

    1986-01-01

    The author considers the problem of metrological compatibility of the two stages in the radiochemical method of determining the activity of a gamma-emitting nuclide: chemical isolation of the nuclide and radiometric measurement of its activity. The authors show that preparation of the specimen in liquid form provides for important advantages compared with the traditional application of the solid residue onto a flat substate. The work here is of interest for analytical chemists who are involved with determination of the activity of gamma emitting nuclides such as Ru 103, Rh 106, Sn 113, Cs 134, Cs 137, La 140, Ce 141, Ce 144, Hg 203, Na 24, Mn 54, Fe 59, Co 60, Zn 65, Zr 95, and Nb 95, for example, in waste water or in emissions to the atmosphere, with the goal of protecting the environment

  15. Pollution characteristics and health risk assessment of volatile organic compounds emitted from different plastic solid waste recycling workshops.

    Science.gov (United States)

    He, Zhigui; Li, Guiying; Chen, Jiangyao; Huang, Yong; An, Taicheng; Zhang, Chaosheng

    2015-04-01

    The pollution profiles of volatile organic compounds (VOCs) emitted from different recycling workshops processing different types of plastic solid waste (PSW) and their health risks were investigated. A total of 64 VOCs including alkanes, alkenes, monoaromatics, oxygenated VOCs (OVOCs), chlorinated VOCs (ClVOCs) and acrylonitrile during the melting extrusion procedure were identified and quantified. The highest concentration of total VOCs (TVOC) occurred in the poly(acrylonitrile-butadiene styrene) (ABS) recycling workshop, followed by the polystyrene (PS), polypropylene (PP), polyamide (PA), polyvinyl chloride (PVC), polyethylene (PE) and polycarbonate (PC) workshops. Monoaromatics were found as the major component emitted from the ABS and PS recycling workshops, while alkanes were mainly emitted from the PE and PP recycling processes, and OVOCs from the PVC and PA recycling workshops. According to the occupational exposure limits' (OEL) assessment, the workers suffered acute and chronic health risks in the ABS and PS recycling workshops. Meanwhile, it was found that most VOCs in the indoor microenvironments were originated from the melting extrusion process, while the highest TVOC concentration was observed in the PS rather than in the ABS recycling workshop. Non-cancer hazard indices (HIs) of all individual VOCs were <1.0, whereas the total HI in the PS recycling workshop was 1.9, posing an adverse chronic health threat. Lifetime cancer risk assessment suggested that the residents also suffered from definite cancer risk in the PS, PA, ABS and PVC recycling workshops. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Electroluminescence Properties of IrQ(ppy)2 Dual-Emitter Organometallic Compound in Organic Light-Emitting Devices

    Science.gov (United States)

    Ciobotaru, Constantin Claudiu; Polosan, Silviu; Ciobotaru, Iulia Corina

    2018-02-01

    This paper reports the influence of the charge carrier mobility on the electroluminescent properties of a dual-emitter organometallic compound dispersed in two conjugated organic small-molecule host materials and embedded in organic light-emitting devices (OLEDs). The electroluminescent processes in OLEDs are strongly influenced by the host-guest interaction. The charge carrier mobility in the host material plays an important role in the electroluminescent processes but also depends on the triplet-triplet interaction with the organometallic compound. The low charge carrier mobility in 4,4'-bis( N-carbazolyl)-1,1'-biphenyl (CBP) host material reduces the electroluminescent processes, but they are slightly enhanced by the triplet-triplet exothermic charge transfer. The higher charge carrier mobility in the case of N, N'-bis(3-methylphenyl)- N, N'-diphenylbenzidine (TPD) host material influences the electroluminescent processes by the endothermic energy transfer at room temperature, which facilitates the triplet-triplet harvesting in the host-guest system. The excitation is transferred to the guest molecules by triplet-triplet interaction as a Dexter transfer, which occurs by endothermic transfer from the triplet exciton in the host to the triplet exciton in the guest.

  17. Active targeting of tumor cells using light emitting bacteria

    International Nuclear Information System (INIS)

    Moon, Sung Min; Min, Jung Joon; Hong, Yeong Jin; Kim, Hyun Ju; Le, Uuenchi N.; Rhee, Joon Haeng; Song, Ho Chun; Heo, Young Jun; Bom, Hee Seung; Choy, Hyon E

    2004-01-01

    The presence of bacteria and viruses in human tumors has been recognized for more than 50 years. Today, with the discovery of bacterial strains that specifically target tumors, and aided by genomic sequencing and genetic engineering, there is new interest in the use of bacteria as tumor vectors. Here, we show that bacteria injected intravenously into live animals entered and replicated in solid tumors and metastases using the novel imaging technology of biophotonics. Bioluminescence operon (LuxCDABE) or fluorescence protein, GFP) has been cloned into pUC19 plasmid to engineer pUC19lux or pUC19gfp. Engineered plasmid was transformed into different kinds of wild type (MG1655) or mutant E. coli (DH5, ppGpp, fnr, purE, crpA, flagella, etc.) strains to construct light emitting bacteria. Xenograft tumor model has been established using CT26 colon cancer cell line. Light emitting bacteria was injected via tail vein into tumor bearing mouse. In vivo bioluminescence imaging has been done after 20 min to 14 days of bacterial injection. We observed localization of tumors by light-emitting E. coli in tumor (CT-26) bearing mice. We confirmed the presence of light-emitting bacteria under the fluorescence microscope with E. coli expressing GFP. Althoug varying mutants strain with deficient invading function has been found in tumor tissues, mutant strains of movement (flagella) couldn't show any light signal from the tumor tissue under the cooled CCD camera, indicating bacteria may actively target the tumor cells. Based on their 'tumor-finding' nature, bacteria may be designed to carry multiple genes or drugs for detection and treatment of cancer, such as prodrug-converting enzymes, toxins, angiogenesis inhibitors and cytokines

  18. One-Step Borylation of 1,3-Diaryloxybenzenes Towards Efficient Materials for Organic Light-Emitting Diodes.

    Science.gov (United States)

    Hirai, Hiroki; Nakajima, Kiichi; Nakatsuka, Soichiro; Shiren, Kazushi; Ni, Jingping; Nomura, Shintaro; Ikuta, Toshiaki; Hatakeyama, Takuji

    2015-11-09

    The development of a one-step borylation of 1,3-diaryloxybenzenes, yielding novel boron-containing polycyclic aromatic compounds, is reported. The resulting boron-containing compounds possess high singlet-triplet excitation energies as a result of localized frontier molecular orbitals induced by boron and oxygen. Using these compounds as a host material, we successfully prepared phosphorescent organic light-emitting diodes exhibiting high efficiency and adequate lifetimes. Moreover, using the present one-step borylation, we succeeded in the synthesis of an efficient, thermally activated delayed fluorescence emitter and boron-fused benzo[6]helicene. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Blue-light emitting triazolopyridinium and triazoloquinolinium salts

    KAUST Repository

    Carboni, Valentina; Su, Xin; Qian, Hai; Aprahamian, Ivan; Credi, Alberto

    2017-01-01

    Compounds that emit blue light are of interest for applications that include optoelectronic devices and chemo/biosensing and imaging. The design and synthesis of small organic molecules that can act as high-efficiency deep-blue-light emitters

  20. Toxic pollutants emitted from thermal decomposition of phthalimide compounds

    Energy Technology Data Exchange (ETDEWEB)

    Chen Kai; Mackie, John C.; Wojtalewicz, Dominika; Kennedy, Eric M. [Process Safety and Environmental Protection Research Group, School of Engineering, The University of Newcastle, Callaghan, New South Wales 2308 (Australia); Dlugogorski, Bogdan Z., E-mail: Bogdan.Dlugogorski@newcastle.edu.au [Process Safety and Environmental Protection Research Group, School of Engineering, University of Newcastle, Callaghan, New South Wales 2308 (Australia)

    2011-03-15

    Phthalimide (PI) and tetrahydrophthalimide (THPI) are two structurally similar compounds extensively used as intermediates for the synthesis of variety of industrial chemicals. This paper investigates the thermal decomposition of PI and THPI under oxygen rich to oxygen lean conditions, quantifying the production of toxicants and explaining their formation pathways. The experiments involved a plug flow reactor followed by silica cartridges, activated charcoal trap and a condenser, with the decomposition products identified and quantified by Fourier transform infrared spectroscopy (FTIR), gas chromatography-mass spectrometry (GC-MS) and micro gas chromatography ({mu}GC). The density functional theory (DFT) calculations served to obtain dissociation energies and reaction pathways, to elucidate the reaction mechanism. The oxidation of PI and THPI produced several toxic nitrogen-containing gases and volatile organic compounds, including hydrogen cyanide, isocyanic acid, nitrogen oxides, benzonitrile, maleimide and tentatively identified benzenemethanimine. The detection of dibenzo-p-dioxin (DD) and dibenzofuran (DF) suggests potential formation of the toxic persistent organic pollutants (POPs) in fires involving PI and THPI, in presence of a chlorine source. The oxidation of THPI produced 2-cyclohexen-1-one, a toxic unsaturated ketone. The results of the present study provide the data for quantitative risk assessments of emissions of toxicants in combustion processes involving PI and THPI.

  1. Toxic pollutants emitted from thermal decomposition of phthalimide compounds

    International Nuclear Information System (INIS)

    Chen Kai; Mackie, John C.; Wojtalewicz, Dominika; Kennedy, Eric M.; Dlugogorski, Bogdan Z.

    2011-01-01

    Phthalimide (PI) and tetrahydrophthalimide (THPI) are two structurally similar compounds extensively used as intermediates for the synthesis of variety of industrial chemicals. This paper investigates the thermal decomposition of PI and THPI under oxygen rich to oxygen lean conditions, quantifying the production of toxicants and explaining their formation pathways. The experiments involved a plug flow reactor followed by silica cartridges, activated charcoal trap and a condenser, with the decomposition products identified and quantified by Fourier transform infrared spectroscopy (FTIR), gas chromatography-mass spectrometry (GC-MS) and micro gas chromatography (μGC). The density functional theory (DFT) calculations served to obtain dissociation energies and reaction pathways, to elucidate the reaction mechanism. The oxidation of PI and THPI produced several toxic nitrogen-containing gases and volatile organic compounds, including hydrogen cyanide, isocyanic acid, nitrogen oxides, benzonitrile, maleimide and tentatively identified benzenemethanimine. The detection of dibenzo-p-dioxin (DD) and dibenzofuran (DF) suggests potential formation of the toxic persistent organic pollutants (POPs) in fires involving PI and THPI, in presence of a chlorine source. The oxidation of THPI produced 2-cyclohexen-1-one, a toxic unsaturated ketone. The results of the present study provide the data for quantitative risk assessments of emissions of toxicants in combustion processes involving PI and THPI.

  2. Fabrication of White Organic Light Emitting Diode Using Two Types of Zn-Complexes as an Emitting Layer.

    Science.gov (United States)

    Kim, Dong-Eun; Kwon, Young-Soo; Shin, Hoon-Kyu

    2015-01-01

    We have studied white OLED using two types of Zn-complexes as an emitting layer. We synthesized brand new two emissive materials, Zn(HPQ)2 as a yellow emitting material and Zn(HPB)2 as a blue emitting material. The Zn-complexes are low-molecular compounds and stable thermally. The fundamental structures of the fabricated OLED was ITO/NPB (40 nm)/Zn(HPB)2 (30 nm)/Zn(HPQ)2/LiF/Al. We varied the thickness of the Zn(HPQ)2 layer by 20, 30, and 40 nm. When the thickness of the Zn(HPQ)2 layer was 20 nm, the white emission was achieved. The maximum luminance was 12,000 cd/m2 at a current density of 800 mA/cm2. The CIE coordinates of the white emission were (0.319, 0.338) at an applied voltage of 10 V.

  3. Biochemical studies on certain biologically active nitrogenous compounds

    International Nuclear Information System (INIS)

    Abdel kader, S.M.; El Sayed, M.M.; El Malt, E.A.; Shaker, E.S.; Abdel Aziz, H.G.

    2010-01-01

    Certain biologically active nitrogenous compounds such as alkaloids are widely distributed in many wild and medicinal plants such as peganum harmala L. (Phycophyllaceae). However, less literature cited on the natural compounds was extracted from the aerial parts of this plant; therefore this study was conducted on harmal leaves using several solvents. Data indicated that methanol extract was the inhibitoriest effect against some pathogenic bacteria, particularly Streptococcus pyogenus. Chromatographic separation illustrated that presence of four compounds; the most active one was the third compound (3). Elementary analysis (C, H, N) revealed that the primary chemical structure of the active antibacterial compound (C3) was: C17 H21 N3 O7 S with molecular weight 411. Spectroscopic analysis proved that coninical structure was = 1- thioformyl, 8?- D glucoperanoside- Bis- 2, 3 dihydroisopyridino pyrrol. This new compound is represented as a noval ?- carboline alkaloid compound

  4. Activity measurement of phosphorus-32 in the presence of pure beta-emitting impurities

    CSIR Research Space (South Africa)

    Simpson, B

    2006-02-27

    Full Text Available Activity measurements undertaken at the CSIR's National Metrology Laboratory (NML) on a solution of the pure beta-emitting radionuclide phosphorus-32, which formed part of an international key comparison, are described. Since exploratory source...

  5. Blue-light emitting triazolopyridinium and triazoloquinolinium salts

    KAUST Repository

    Carboni, Valentina

    2017-01-27

    Compounds that emit blue light are of interest for applications that include optoelectronic devices and chemo/biosensing and imaging. The design and synthesis of small organic molecules that can act as high-efficiency deep-blue-light emitters in the solid state and can be easily processed from solutions represents a significant challenge. Herein we present the preparation and photophysical, photochemical and electrochemical properties of a series of triazolopyridinium and triazoloquinolinium compounds. The compounds are soluble in water or polar organic solvents and exhibit photoluminescence in the blue region of the spectrum in fluid solution, in the solid state and in a frozen matrix.

  6. Activity measurement of phosphorus-32 in the presence of pure beta-emitting impurities

    CSIR Research Space (South Africa)

    Simpson, BRS

    2006-01-01

    Full Text Available Authors describe the activity measurements undertaken at the CSIR’s National Metrology Laboratory on a solution of the pure beta emitting Radio nuclide phosphorus-32 that formed part of an international key comparison. Depending on the production...

  7. Blue emitting organic semiconductors under high pressure

    DEFF Research Database (Denmark)

    Knaapila, Matti; Guha, Suchismita

    2016-01-01

    This review describes essential optical and emerging structural experiments that use high GPa range hydrostatic pressure to probe physical phenomena in blue-emitting organic semiconductors including π-conjugated polyfluorene and related compounds. The work emphasizes molecular structure and inter......This review describes essential optical and emerging structural experiments that use high GPa range hydrostatic pressure to probe physical phenomena in blue-emitting organic semiconductors including π-conjugated polyfluorene and related compounds. The work emphasizes molecular structure...... and intermolecular self-organization that typically determine transport and optical emission in π-conjugated oligomers and polymers. In this context, hydrostatic pressure through diamond anvil cells has proven to be an elegant tool to control structure and interactions without chemical intervention. This has been...... and intermolecular interactions on optical excitations, electron–phonon interaction, and changes in backbone conformations. This picture is connected to the optical high pressure studies of other π-conjugated systems and emerging x-ray scattering experiments from polyfluorenes which provides a structure-property map...

  8. Top-emitting organic light-emitting diodes.

    Science.gov (United States)

    Hofmann, Simone; Thomschke, Michael; Lüssem, Björn; Leo, Karl

    2011-11-07

    We review top-emitting organic light-emitting diodes (OLEDs), which are beneficial for lighting and display applications, where non-transparent substrates are used. The optical effects of the microcavity structure as well as the loss mechanisms are discussed. Outcoupling techniques and the work on white top-emitting OLEDs are summarized. We discuss the power dissipation spectra for a monochrome and a white top-emitting OLED and give quantitative reports on the loss channels. Furthermore, the development of inverted top-emitting OLEDs is described.

  9. Antimicrobial activity of some potential active compounds against ...

    African Journals Online (AJOL)

    Antimicrobial activities of six potential active compounds (acetic acid, chitosan, catechin, gallic acid, lysozyme, and nisin) at the concentration of 500 g/ml against the growth of Escherichia coli, Staphylococcus aureus, Listeria innocua, and Saccharomyces cerevisiae were determined. Lysozyme showed the highest ...

  10. The line-emitting gas in active galaxies - A probe of the nuclear engine

    Science.gov (United States)

    Veilleux, Sylvain

    1993-01-01

    This paper reviews some of the basic questions regarding the structure of the engine powering active galactic nuclei (AGN), the nature of the interaction between the AGN and the host galaxy, and the origin and evolution of AGN. The study of the dynamics and physical characteristics of the line-emitting gas in these objects has proven fruitful in addressing many of these issues. Recent advances in optical and infrared detector technology combined with the development of superior ground-based instruments have produced efficient new tools for the study of the line-emitting gas on nuclear and Galactic scales. Programs which take advantage of two of these new techniques, Fabry-Perot imaging spectroscopy and infrared spectroscopy, are described in this paper. The origin of nuclear activity in galaxies is also addressed in a third project which aims at determining the nature of luminous infrared galaxies.

  11. Efficient red organic light-emitting diode sensitized by a phosphorescent Ir compound

    Energy Technology Data Exchange (ETDEWEB)

    Wang, X.R. [School of Material Science and Engineering, Shanghai University, Jiading, Shanghai 201800 (China); You, H. [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Graduate School of the Chinese Academy of Sciences, Changchun, Jilin 130022 (China); Tang, H. [School of Material Science and Engineering, Shanghai University, Jiading, Shanghai 201800 (China); Ding, G.H. [Institute of Advanced Materials and Fine Chemicals, East China University of Science and Technology, Shanghai 200237 (China); Ma, D.G. [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Graduate School of the Chinese Academy of Sciences, Changchun, Jilin 130022 (China); Tian, H. [Institute of Advanced Materials and Fine Chemicals, East China University of Science and Technology, Shanghai 200237 (China); Sun, R.G. [School of Material Science and Engineering, Shanghai University, Jiading, Shanghai 201800 (China)], E-mail: runguangsun@126.com

    2008-01-15

    The efficiencies of red organic light-emitting diode (OLED) using tris-(8-hydroxy-quinoline)aluminum (Alq{sub 3}) as host and 4-(dicyanomethylene)-2-t-butyl-6-(1,1,7,7-tetramethyljulolidyl-9-enyl) -4H-pyra n (DCJTB) as dopant were greatly increased by adding a small amount (0.3 wt%) of Ir compound, iridium(III) bis(3-(2-benzothiazolyl)-7-(diethylamino)-2H-1-benzopyran-2-onato-N',C{sup 4}) (acetyl acetonate) (Ir(C6){sub 2}(acac)), as a sensitizer. The device has a sandwiched structure of indium tin oxide (ITO)/4,4',4''-tris(N-(2-naphthyl)-N-phenyl-amino)triphenylamine (T-NATA) (40 nm)/N,N'-bis(1-naphthyl)-N,N'-diphenyl-1,1'-biphenyl-4,4' diamine (NPB) (40 nm)/Alq{sub 3}:DCJTB (0.7 wt%):Ir(C6){sub 2}(acac) (0.3 wt%) (40 nm)/Alq{sub 3} (40 nm)/LiF (1 nm)/Al (120 nm). It can be seen that the current efficiencies of this device remained almost (13.8{+-}1) cd/A from 0.1 to 20,000 cd/m{sup 2} and the Commission International d'Eclairage (CIE) coordinates at (0.60, 0.37) in the range of wide brightness. The significant improvement was attributed to the sensitization effect of the doped Ir(C6){sub 2}(acac), thus the energy of singlet and triplet excitons is simultaneously transferred to the DCJTB.

  12. Activity of Polyphenolic Compounds against Candida glabrata

    Directory of Open Access Journals (Sweden)

    Ricardo Salazar-Aranda

    2015-09-01

    Full Text Available Opportunistic mycoses increase the morbidity and mortality of immuno-compromised patients. Five Candida species have been shown to be responsible for 97% of worldwide cases of invasive candidiasis. Resistance of C. glabrata and C. krusei to azoles has been reported, and new, improved antifungal agents are needed. The current study was designed to evaluatethe activity of various polyphenolic compounds against Candida species. Antifungal activity was evaluated following the M27-A3 protocol of the Clinical and Laboratory Standards Institute, and antioxidant activity was determined using the DPPH assay. Myricetin and baicalein inhibited the growth of all species tested. This effect was strongest against C. glabrata, for which the minimum inhibitory concentration (MIC value was lower than that of fluconazole. The MIC values against C. glabrata for myricitrin, luteolin, quercetin, 3-hydroxyflavone, and fisetin were similar to that of fluconazole. The antioxidant activity of all compounds was confirmed, and polyphenolic compounds with antioxidant activity had the greatest activity against C. glabrata. The structure and position of their hydroxyl groups appear to influence their activity against C. glabrata.

  13. Structure Modification of an Active Azo-Compound as a Route to New Antimicrobial Compounds

    Directory of Open Access Journals (Sweden)

    Simona Concilio

    2017-05-01

    Full Text Available Some novel (phenyl-diazenylphenols 3a–g were designed and synthesized to be evaluated for their antimicrobial activity. A previously synthesized molecule, active against bacteria and fungi, was used as lead for modifications and optimization of the structure, by introduction/removal or displacement of hydroxyl groups on the azobenzene rings. The aim of this work was to evaluate the consequent changes of the antimicrobial activity and to validate the hypothesis that, for these compounds, a plausible mechanism could involve an interaction with protein receptors, rather than an interaction with membrane. All newly synthesized compounds were analyzed by 1H-NMR, DSC thermal analysis and UV-Vis spectroscopy. The in vitro minimal inhibitory concentrations (MIC of each compound was determined against Gram-positive and Gram-negative bacteria and Candida albicans. Compounds 3b and 3g showed the highest activity against S. aureus and C. albicans, with remarkable MIC values of 10 µg/mL and 3 µg/mL, respectively. Structure-activity relationship studies were capable to rationalize the effect of different substitutions on the phenyl ring of the azobenzene on antimicrobial activity.

  14. Synthesis, biological activity and computational studies of novel azo-compounds

    International Nuclear Information System (INIS)

    Ashraf, J.; Murtaza, S.; Mughal, E.U.; Sadiq, A.

    2017-01-01

    In the present protocol, we report the synthesis and characterization of some novel azo-compounds starting from 4-methoxyaniline and 4-aminophenazone, which were diazotized at low temperature. 4-nitrophenol, 2-aminobenzoic acid, benzamide, 4-aminobenzoic acid, resorcinol, o-bromonitrobenzene and 2-nitroaniline were used as active aromatic coupling compounds for the second step. The synthesized compounds were investigated for their potential antibacterial activities by using disc diffusion method against Escherichia coli, Shigellasonnei, Streptococcus pyrogenes, Staphylococcus aureus and Neisseria gonorrhoeae strains. They were also subjected to antioxidant activities by using DPPH method. Results revealed that the compounds of 4-methoxyaniline and 4-aminophenazone showed good antibacterial activity against all strains, where as some azo-compounds have moderate to good antioxidant activities. Furthermore, these compounds were studied by computational analysis. (author)

  15. A Structure-Activity Relationship (SAR Study of Neolignan Compounds with Anti-schistosomiasis Activity

    Directory of Open Access Journals (Sweden)

    Alves Claúdio N.

    2002-01-01

    Full Text Available A set of eighteen neolignan derivative compounds with anti-schistosomiasis activity was studied by using the quantum mechanical semi-empirical method PM3 and other theoretical methods in order to calculate selected molecular properties (variables or descriptors to be correlated to their biological activities. Exploratory data analysis (principal component analysis, PCA, and hierarchical cluster analysis, HCA, discriminant analysis (DA and the Kth nearest neighbor (KNN method were employed for obtaining possible relationships between the calculated descriptors and the biological activities studied and predicting the anti-schistosomiasis activity of new compounds from a test set. The molecular descriptors responsible for the separation between active and inactive compounds were: hydration energy (HE, molecular refractivity (MR and charge on the C19 carbon atom (Q19. These descriptors give information on the kind of interaction that can occur between the compounds and their respective biological receptor. The prediction study was done with a new set of ten derivative compounds by using the PCA, HCA, DA and KNN methods and only five of them were predicted as active against schistosomiasis.

  16. Insecticidal Activity of Cyanohydrin and Monoterpenoid Compounds

    Directory of Open Access Journals (Sweden)

    Joel R. Coats

    2000-04-01

    Full Text Available The insecticidal activities of several cyanohydrins, cyanohydrin esters and monoterpenoid esters (including three monoterpenoid esters of a cyanohydrin were evaluated. Topical toxicity to Musca domestica L. adults was examined, and testing of many compounds at 100 mg/fly resulted in 100% mortality. Topical LD50 values of four compounds for M. domestica were calculated. Testing of many of the reported compounds to brine shrimp (Artemia franciscana Kellog resulted in 100% mortality at 10 ppm, and two compounds caused 100% mortality at 1 ppm. Aquatic LC50 values were calculated for five compounds for larvae of the yellow fever mosquito (Aedes aegypti (L.. Monoterpenoid esters were among the most toxic compounds tested in topical and aquatic bioassays.

  17. Volatiles emitted from flowers of gamma-radiated and nonradiated Jasminum polyanthum Franch

    DEFF Research Database (Denmark)

    Christensen, Lars P; Jakobsen, Henrik B; Kristiansen, Kell

    1997-01-01

    Volatile compounds emitted from flowers of Jasminum polyanthum Pepita in situ were collected by dynamic headspace technique and analyzed by GC-FID and GC-MS. A total of 32 compounds were identified. The flower scent was dominated by benzyl acetate (57.8%), p-cresol (12.2%), (E)-isoeugenol (9.7%),...

  18. Novel asymmetrical pyrene derivatives as light emitting materials: Synthesis and photophysics

    International Nuclear Information System (INIS)

    Li Yang; Wang Dong; Wang Lei; Li Zhengqiang; Cui Qing; Zhang Haiquan; Yang Huai

    2012-01-01

    A series of novel substituted pyrene derivatives with asymmetrical groups have been successfully synthesized in excellent yield. Structures of the asymmetrical compound were fully characterized by 1 H-NMR, IR spectroscopy and mass spectrometry. By introducing ethynyl functions to pyrene, we obtained highly efficient blue and green light emitting materials. It has been demonstrated that the emission characteristics of pyrene derivatives have been bathochromatically tuned in the visible region by extending the π-conjugation. The photophysical properties of these compounds were carefully examined in different organic solvents and different concentrations. The electrochemical properties and geometrical electronic structures of the new pyrene derivatives have been investigated by cyclic voltammograms and density functional theory (DFT) calculations. - Highlights: ► It is the first research about asymmetrial pyrene derivatives as highly efficient light emitting materials. ► The solvatochromism and concentration effect of the new compounds have been discussed. ► Furthermore, the electrochemical properties and geometrical electronic structures were also investigated in this paper.

  19. 'Serial review on clinical PET tracers'. Manufacturing and quality control of positron emitting radiopharmaceuticals produced by in-house cyclotron

    International Nuclear Information System (INIS)

    Saji, Hideo

    2009-01-01

    In order to establish PET diagnosis as a routine clinical tool, manufacture's compliance with regulations under the Good Manufacturing Practice (GMP) principle for PET radiopharmaceuticals is necessary. For this purpose, the Sub-committee on Medical Application of Positron Emitting Radionuclides, Medical Science and Pharmaceutical Committee of Japan Radioisotopes Association has proposed 'Standards for Compounds Labeled with Emitting Radionuclides Approved as Established Techniques for Medical Use'. This guideline includes the general notices, general rules for preparations, general tests for the quality control, quality of each PET agents, guideline for manufacturing environment and manufacturing process at manufacturing facilities of PET agents. Each facility should have a committee and establish an internal system to account for manufacturing compounds labeled with positron emitting radionuclides produced in the facility, and compile standards by referring to the 'Established Standard Techniques of Labeling Compounds with Emitting Radionuclides for use as Radiopharmaceuticals: approved by the Subcommittee on Medical Application of Cyclotron-Produced Radionuclides (revised in 2009)', in order to maintain the quality of radiopharmaceuticals. (author)

  20. Compound Structure-Independent Activity Prediction in High-Dimensional Target Space.

    Science.gov (United States)

    Balfer, Jenny; Hu, Ye; Bajorath, Jürgen

    2014-08-01

    Profiling of compound libraries against arrays of targets has become an important approach in pharmaceutical research. The prediction of multi-target compound activities also represents an attractive task for machine learning with potential for drug discovery applications. Herein, we have explored activity prediction in high-dimensional target space. Different types of models were derived to predict multi-target activities. The models included naïve Bayesian (NB) and support vector machine (SVM) classifiers based upon compound structure information and NB models derived on the basis of activity profiles, without considering compound structure. Because the latter approach can be applied to incomplete training data and principally depends on the feature independence assumption, SVM modeling was not applicable in this case. Furthermore, iterative hybrid NB models making use of both activity profiles and compound structure information were built. In high-dimensional target space, NB models utilizing activity profile data were found to yield more accurate activity predictions than structure-based NB and SVM models or hybrid models. An in-depth analysis of activity profile-based models revealed the presence of correlation effects across different targets and rationalized prediction accuracy. Taken together, the results indicate that activity profile information can be effectively used to predict the activity of test compounds against novel targets. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Phenolic Compounds and Antioxidant Activities of Liriope muscari

    Directory of Open Access Journals (Sweden)

    Shu Shan Du

    2012-02-01

    Full Text Available Five phenolic compounds, namely N-trans-coumaroyltyramine (1, N-trans-feruloyltyramine (2, N-trans-feruloyloctopamine (3, 5,7-dihydroxy-8-methoxyflavone (4 and (3S3,5,4′-trihydroxy-7-methoxy-6-methylhomoisoflavanone (5, were isolated from the fibrous roots of Liriope muscari (Liliaceae. Compounds 2–5 were isolated for the first time from the Liriope genus. Their in vitro antioxidant activities were assessed by the DPPH and ABTS scavenging methods with microplate assays. The structure-activity relationships of compounds 1–3 are discussed.

  2. New fluorescent dipolar pyrazine derivatives for non-doped red organic light-emitting diodes

    International Nuclear Information System (INIS)

    Gao Baoxiang; Zhou Quanguo; Geng Yanhou; Cheng Yanxiang; Ma Dongge; Xie Zhiyuan; Wang Lixiang; Wang Fosong

    2006-01-01

    Dipolar fluorescent compounds containing electron-accepting pyrazine-2,3-dicarbonitrile and electron-donating arylamine moiety have been designed and synthesized. The optical and electrochemical properties of these compounds can be adjusted by changing π-bridge length and the donor (D) strength. Organic light-emitting devices based on these compounds are fabricated. Saturated red emission of (0.67, 0.33) and the external quantum efficiency as high as 1.41% have been demonstrated for one of these compounds

  3. Prediction of Positions of Active Compounds Makes It Possible To Increase Activity in Fragment-Based Drug Development

    Directory of Open Access Journals (Sweden)

    Yoshifumi Fukunishi

    2011-05-01

    Full Text Available We have developed a computational method that predicts the positions of active compounds, making it possible to increase activity as a fragment evolution strategy. We refer to the positions of these compounds as the active position. When an active fragment compound is found, the following lead generation process is performed, primarily to increase activity. In the current method, to predict the location of the active position, hydrogen atoms are replaced by small side chains, generating virtual compounds. These virtual compounds are docked to a target protein, and the docking scores (affinities are examined. The hydrogen atom that gives the virtual compound with good affinity should correspond to the active position and it should be replaced to generate a lead compound. This method was found to work well, with the prediction of the active position being 2 times more efficient than random synthesis. In the current study, 15 examples of lead generation were examined. The probability of finding active positions among all hydrogen atoms was 26%, and the current method accurately predicted 60% of the active positions.

  4. Phenolic compounds and antioxidant activity of edible flowers

    Directory of Open Access Journals (Sweden)

    Marta Natalia Skrajda

    2017-08-01

    Full Text Available Introduction: Edible flowers has been used for thousands of years. They increase aesthetic appearance of food, but more often they are mentioned in connection with biologically active substances. The main ingredient of the flowers is water, which accounts for more than 80%. In small amounts, there are also proteins, fat, carbohydrates, fiber and minerals. Bioactive substances such as carotenoids and phenolic compounds determine the functional properties of edible flowers. Aim: The aim of this work was to characterize the phenolic compounds found in edible flowers and compare their antioxidant activity. Results: This review summarizes current knowledge about the usage of edible flowers for human nutrition. The work describes the antioxidant activity and phenolic compounds of some edible flowers. Based on literature data there is a significant difference both in content of phenolic compounds and antioxidant activity between edible flowers. These difference reaches up to 3075-fold in case of antioxidant potential. Among described edible flowers the most distinguishable are roses, peonies, osmanthus fragans and sambuco nero. Conclusions: Edible flowers are the new source of nutraceuticals due to nutritional and antioxidant values.

  5. Antioxidant Activity of Phenolic Compounds from Fava Bean Sprouts.

    Science.gov (United States)

    Okumura, Koharu; Hosoya, Takahiro; Kawarazaki, Kai; Izawa, Norihiko; Kumazawa, Shigenori

    2016-06-01

    Fava beans are eaten all over the world and recently, marketing for their sprouts began in Japan. Fava bean sprouts contain more polyphenols and l-3,4-dihydroxyphenylalanine (l-DOPA) than the bean itself. Our antioxidant screening program has shown that fava bean sprouts also possess a higher antioxidant activity than other commercially available sprouts and mature beans. However, the individual constituents of fava bean sprouts are not entirely known. In the present study, we investigated the phenolic compounds of fava bean sprouts and their antioxidant activity. Air-dried fava bean sprouts were treated with 80% methanol and the extract was partitioned in water with chloroform and ethyl acetate. HPLC analysis had shown that the ethyl acetate-soluble parts contained phenolic compounds, separated by preparative HPLC to yield 5 compounds (1-5). Structural analysis using NMR and MS revealed that the compounds isolated were kaempferol glycosides. All isolated compounds had an α-rhamnose at the C-7 position with different sugars attached at the C-3 position. Compounds 1-5 had β-galactose, β-glucose, α-rhamnose, 6-acetyl-β-galactose and 6-acetyl-β-glucose, respectively, at the C-3 position. The amount of l-DOPA in fava bean sprouts was determined by the quantitative (1) H NMR technique. The l-DOPA content was 550.45 mg ± 11.34 /100 g of the raw sprouts. The antioxidant activities of compounds 2-5 and l-DOPA were evaluated using the 2,2-diphenyl-1-picrylhydrazyl scavenging assay. l-DOPA showed high antioxidant activity, but the isolated kaempferol glycosides showed weak activity. Therefore, it can be suggested that l-DOPA contributed to the antioxidant activity of fava bean sprouts. © 2016 Institute of Food Technologists®

  6. Simultaneous Activation of Iron- and Thiol-Based Sensor-Regulator Systems by Redox-Active Compounds.

    Science.gov (United States)

    Lee, Kang-Lok; Yoo, Ji-Sun; Oh, Gyeong-Seok; Singh, Atul K; Roe, Jung-Hye

    2017-01-01

    Bacteria in natural habitats are exposed to myriad redox-active compounds (RACs), which include producers of reactive oxygen species (ROS) and reactive electrophile species (RES) that alkylate or oxidize thiols. RACs can induce oxidative stress in cells and activate response pathways by modulating the activity of sensitive regulators. However, the effect of a certain compound on the cell has been investigated primarily with respect to a specific regulatory pathway. Since a single compound can exert multiple chemical effects in the cell, its effect can be better understood by time-course monitoring of multiple sensitive regulatory pathways that the compound induces. We investigated the effect of representative RACs by monitoring the activity of three sensor-regulators in the model actinobacterium Streptomyces coelicolor ; SoxR that senses reactive compounds directly through oxidation of its [2Fe-2S] cluster, CatR/PerR that senses peroxides through bound iron, and an anti-sigma factor RsrA that senses RES via disulfide formation. The time course and magnitude of induction of their target transcripts were monitored to predict the chemical activities of each compound in S. coelicolor . Phenazine methosulfate (PMS) was found to be an effective RAC that directly activated SoxR and an effective ROS-producer that induced CatR/PerR with little thiol-perturbing activity. p -Benzoquinone was an effective RAC that directly activated SoxR, with slower ROS-producing activity, and an effective RES that induced the RsrA-SigR system. Plumbagin was an effective RAC that activated SoxR, an effective ROS-producer, and a less agile but effective RES. Diamide was an RES that effectively formed disulfides and a weak RAC that activated SoxR. Monobromobimane was a moderately effective RES and a slow producer of ROS. Interestingly, benzoquinone induced the SigR system by forming adducts on cysteine thiols in RsrA, revealing a new pathway to modulate RsrA activity. Overall, this study showed

  7. The dynamic behavior of thin-film ionic transition metal complex-based light-emitting electrochemical cells

    Energy Technology Data Exchange (ETDEWEB)

    Meier, Sebastian B., E-mail: sebastian.meier@belectric.com, E-mail: wiebke.sarfert@siemens.com [Department of Materials Science VI: Materials for Electronics and Energy Technology, Friedrich-Alexander-University of Erlangen-Nuremberg, 91058 Erlangen (Germany); Siemens AG, Corporate Technology, CT RTC MAT IEC-DE, 91058 Erlangen (Germany); Hartmann, David; Sarfert, Wiebke, E-mail: sebastian.meier@belectric.com, E-mail: wiebke.sarfert@siemens.com [Siemens AG, Corporate Technology, CT RTC MAT IEC-DE, 91058 Erlangen (Germany); Winnacker, Albrecht [Department of Materials Science VI: Materials for Electronics and Energy Technology, Friedrich-Alexander-University of Erlangen-Nuremberg, 91058 Erlangen (Germany)

    2014-09-14

    Light-emitting electrochemical cells (LECs) have received increasing attention during recent years due to their simple architecture, based on solely air-stabile materials, and ease of manufacture in ambient atmosphere, using solution-based technologies. The LEC's active layer offers semiconducting, luminescent as well as ionic functionality resulting in device physical processes fundamentally different as compared with organic light-emitting diodes. During operation, electrical double layers (EDLs) form at the electrode interfaces as a consequence of ion accumulation and electrochemical doping sets in leading to the in situ development of a light-emitting p-i-n junction. In this paper, we comment on the use of impedance spectroscopy in combination with complex nonlinear squares fitting to derive key information about the latter events in thin-film ionic transition metal complex-based light-emitting electrochemical cells based on the model compound bis-2-phenylpyridine 6-phenyl-2,2´-bipyridine iridium(III) hexafluoridophosphate ([Ir(ppy)₂(pbpy)][PF₆]). At operating voltages below the bandgap potential of the ionic complex used, we obtain the dielectric constant of the active layer, the conductivity of mobile ions, the transference numbers of electrons and ions, and the thickness of the EDLs, whereas the transient thickness of the p-i-n junction is determined at voltages above the bandgap potential. Most importantly, we find that charge transport is dominated by the ions when carrier injection from the electrodes is prohibited, that ion movement is limited by the presence of transverse internal interfaces and that the width of the intrinsic region constitutes almost 60% of the total active layer thickness in steady state at a low operating voltage.

  8. SPECTRAL CHARACTERISTICS OF MID-INFRARED LIGHT-EMITTING DIODES BASED ON InAs (Sb,P

    Directory of Open Access Journals (Sweden)

    N. K. Zhumashev

    2016-01-01

    Full Text Available Subject of Study. We consider spectral characteristics of mid-infrared light-emitting diodes with heterostructures based on InAs(Sb,P emitting at T=300 K in the wavelength range 3.4–4.1 micrometers. The aim of the study was to search for the ways of increasing the diode efficiency. Methods. The heterostructures were grown from metal-organic chemical compounds with the use of vapor-phase epitaxial technique. The spectra were recorded under pulse excitation with the use of computer-controlled installation employing MDR-23 grating monochromator and a lock-in amplifier. InSb photodiode was used as a detector. Comparative study of electroluminescence spectra of the diodes was carried out at the temperatures equal to 300 K and 77 K. We compared the obtained data with the calculation results of the band diagrams of the heterostructures. Main Results. As a result of comparative study of the electroluminescence spectra of the diodes recorded at 300 K and 77 K we have established that increasing of their efficiency is hindered by substantial influence of Auger recombination. For the first time at 77 К we have observed the effect of stimulated emission from InAsSb active layer in light-emitting structures made of InAs/InAsSb/InAsSbP. For heterostructures with quantum wells InAs/(InAs/InAsSb/InAsSbP we have found out that at 77 К the carrier recombination occurs outside quantum wells, which points out to the insufficient carrier localization in the active layer. Thus, we have shown that the efficiency of mid-infrared light-emitting diodes based on InAs(Sb,P can be increased via suppression of Auger-recombination and improvement of carrier localization in the active region. Practical Relevance. The results of the study can be used for development of heterostructures for mid-infrared light-emitting diodes.

  9. Minicyclotron-based technology for the production of positron-emitting labelled radiopharmaceuticals

    International Nuclear Information System (INIS)

    Barrio, J.R.; Bida, G.; Satyamurthy, N.; Padgett, H.C.; MacDonald, N.S.; Phelps, M.E.

    1983-01-01

    The use of short-lived positron emitters such as carbon 11, fluorine 18, nitrogen 13, and oxygen 15, together with positron-emission tomography (PET) for probing the dynamics of physiological and biochemical processes in the normal and diseased states in man is presently an active area of research. One of the pivotal elements for the continued growth and success of PET is the routine delivery of the desired positron emitting labelled compounds. To date, the cyclotron remains the accelerator of choice for production of medically useful radionuclides. The development of the technology to bring the use of cyclotrons to a clinical setting is discussed

  10. Minicyclotron-based technology for the production of positron-emitting labelled radiopharmaceuticals

    Energy Technology Data Exchange (ETDEWEB)

    Barrio, J.R.; Bida, G.; Satyamurthy, N.; Padgett, H.C.; MacDonald, N.S.; Phelps, M.E.

    1983-01-01

    The use of short-lived positron emitters such as carbon 11, fluorine 18, nitrogen 13, and oxygen 15, together with positron-emission tomography (PET) for probing the dynamics of physiological and biochemical processes in the normal and diseased states in man is presently an active area of research. One of the pivotal elements for the continued growth and success of PET is the routine delivery of the desired positron emitting labelled compounds. To date, the cyclotron remains the accelerator of choice for production of medically useful radionuclides. The development of the technology to bring the use of cyclotrons to a clinical setting is discussed. (ACR)

  11. Antioxidative Activities and Active Compounds of Extracts from Catalpa Plant Leaves

    Directory of Open Access Journals (Sweden)

    Hongyu Xu

    2014-01-01

    Full Text Available In order to screen the Catalpa plant with high antioxidant activity and confirm the corresponding active fractions from Catalpa ovata G. Don, C. fargesii Bur., and C. bungei C. A. Mey., total flavonoid contents and antioxidant activities of the extracts/fractions of Catalpa plant leaves were determined. The determined total flavonoid content and antioxidant activity were used as assessment criteria. Those compounds with antioxidant activity were isolated with silica gel column chromatography and ODS column chromatography. Our results showed that the total flavonoid content in C. bungei C. A. Mey. (30.07 mg/g·DW was the highest, followed by those in C. fargesii Bur. (25.55 mg/g·DW and C. ovata G. Don (24.96 mg/g·DW. According to the determination results of total flavonoid content and antioxidant activity in 3 clones of leaves of C. bungei C. A. Mey., the total flavonoid content and antioxidant activity in crude extracts from C. bungei C. A. Mey. 6 (CA6 leaves were the highest. Moreover, the results showed that the total flavonoid content and antioxidant activities of ethyl acetate (EA fraction in ethanol crude extracts in CA6 leaves were the highest, followed by n-butanol, petroleum ether (PE, and water fractions. Two flavonoid compounds with antioxidant activity were firstly isolated based on EA fraction. The two compounds were luteolin (1 and apigenin (2, respectively.

  12. Effect of Dopant Activation on Device Characteristics of InGaN-based Light Emitting Diodes

    Science.gov (United States)

    Lacroce, Nicholas; Liu, Guangyu; Tan, Chee-Keong; Arif, Ronald A.; Lee, Soo Min; Tansu, Nelson

    2015-03-01

    Achieving high uniformity in growths and device characteristics of InGaN-based light-emitting diodes (LEDs) is important for large scale manufacturing. Dopant activation and maintaining control of variables affecting dopant activation are critical steps in the InGaN-based light emitting diodes (LEDs) fabrication process. In the epitaxy of large scale production LEDs, in-situ post-growth annealing is used for activating the Mg acceptor dopant in the p-AlGaN and p-GaN of the LEDs. However, the annealing temperature varies with respect to position in the reactor chamber, leading to severe uniform dopant activation issue across the devices. Thus, it is important to understand how the temperature gradient and the resulting variance in Mg acceptor activation will alter the device properties. In this work, we examine the effect of varying p-type doping levels in the p-GaN layers and AlGaN electron blocking layer of the GaN LEDs on the optoelectronic properties including the band profile, carrier concentration, current density, output power and quantum efficiency. By understanding the variations and its effect, the identification of the most critical p-type doping layer strategies to address this variation will be clarified.

  13. High-efficiency white organic light-emitting diodes using thermally activated delayed fluorescence

    International Nuclear Information System (INIS)

    Nishide, Jun-ichi; Hiraga, Yasuhide; Nakanotani, Hajime; Adachi, Chihaya

    2014-01-01

    White organic light-emitting diodes (WOLEDs) have attracted much attention recently, aimed for next-generation lighting sources because of their high potential to realize high electroluminescence efficiency, flexibility, and low-cost manufacture. Here, we demonstrate high-efficiency WOLED using red, green, and blue thermally activated delayed fluorescence materials as emissive dopants to generate white electroluminescence. The WOLED has a maximum external quantum efficiency of over 17% with Commission Internationale de l'Eclairage coordinates of (0.30, 0.38).

  14. Aerobic biodegradation of organotin compounds in activated sludge batch reactors

    Energy Technology Data Exchange (ETDEWEB)

    Stasinakis, Athanasios S. [Department of Environmental Studies, Water and Air Quality Laboratory, University of the Aegean, University Hill, Mytilene 81 100 (Greece)]. E-mail: astas@env.aegean.gr; Thomaidis, Nikolaos S. [Laboratory of Analytical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Zografou, Athens 157 71 (Greece); Nikolaou, Anastasia [Department of Environmental Studies, Water and Air Quality Laboratory, University of the Aegean, University Hill, Mytilene 81 100 (Greece); Kantifes, Andreas [Department of Environmental Studies, Water and Air Quality Laboratory, University of the Aegean, University Hill, Mytilene 81 100 (Greece)

    2005-04-01

    The biodegradation behavior of four organotin (OT) compounds, namely tributyltin (TBT), dibutyltin (DBT), monobutyltin (MBT) and triphenyltin (TPhT), was studied in lab-scale activated sludge batch reactors. The activated sludge was spiked with the OT compounds at a level of 100 {mu}g l{sup -1} as Sn. Determination of the OT compounds by GC-FPD after ethylation in the dissolved and particulate phase revealed that 24 h after the start of the experiments, almost the total of OT compounds has been removed from the dissolved phase and is associated with the suspended solids. Calculation of mass balance in batch reactors showed that OT compounds biodegradation was performed via a sequential dealkylation process. Removals due to biodegradation were differentiated according to the parent compound. In experiments with non-acclimatized biomass, a percentage of 27.1, 8.3, 73.8 and 51.3 was still present as TBT, DBT, MBT and TPhT, respectively, at the end of the experiment (18th day). Half-lives (t{sub 1/2}) of 10.2 and 5.1 days were calculated for TBT and DBT, respectively, whereas apparent t{sub 1/2} values could not be determined for MBT and TPhT (t{sub 1/2} > 18 days). The capacity of activated sludge to biodegrade OT compounds in the absence of supplemental substrate indicated that these compounds can be metabolized as single sources of carbon and energy in activated sludge systems. Excluding TBT, the presence of low concentrations of supplemental substrate did not affect the biodegradation potential of activated sludge. The acclimatization of biomass on OT compounds enhanced significantly biodegradation, resulting in significant decreases of half-lives of OT compounds. As a result in the presence of acclimatized biomass, half-lives of 1.4, 3.6, 9.8 and 5.0 days were calculated for TBT, DBT, MBT and TPhT, respectively. - The fate of organotins is assessed in activated sludge systems.

  15. Aerobic biodegradation of organotin compounds in activated sludge batch reactors

    International Nuclear Information System (INIS)

    Stasinakis, Athanasios S.; Thomaidis, Nikolaos S.; Nikolaou, Anastasia; Kantifes, Andreas

    2005-01-01

    The biodegradation behavior of four organotin (OT) compounds, namely tributyltin (TBT), dibutyltin (DBT), monobutyltin (MBT) and triphenyltin (TPhT), was studied in lab-scale activated sludge batch reactors. The activated sludge was spiked with the OT compounds at a level of 100 μg l -1 as Sn. Determination of the OT compounds by GC-FPD after ethylation in the dissolved and particulate phase revealed that 24 h after the start of the experiments, almost the total of OT compounds has been removed from the dissolved phase and is associated with the suspended solids. Calculation of mass balance in batch reactors showed that OT compounds biodegradation was performed via a sequential dealkylation process. Removals due to biodegradation were differentiated according to the parent compound. In experiments with non-acclimatized biomass, a percentage of 27.1, 8.3, 73.8 and 51.3 was still present as TBT, DBT, MBT and TPhT, respectively, at the end of the experiment (18th day). Half-lives (t 1/2 ) of 10.2 and 5.1 days were calculated for TBT and DBT, respectively, whereas apparent t 1/2 values could not be determined for MBT and TPhT (t 1/2 > 18 days). The capacity of activated sludge to biodegrade OT compounds in the absence of supplemental substrate indicated that these compounds can be metabolized as single sources of carbon and energy in activated sludge systems. Excluding TBT, the presence of low concentrations of supplemental substrate did not affect the biodegradation potential of activated sludge. The acclimatization of biomass on OT compounds enhanced significantly biodegradation, resulting in significant decreases of half-lives of OT compounds. As a result in the presence of acclimatized biomass, half-lives of 1.4, 3.6, 9.8 and 5.0 days were calculated for TBT, DBT, MBT and TPhT, respectively. - The fate of organotins is assessed in activated sludge systems

  16. The mast cell degranulator compound 48/80 directly activates neurons.

    Directory of Open Access Journals (Sweden)

    Michael Schemann

    Full Text Available BACKGROUND: Compound 48/80 is widely used in animal and tissue models as a "selective" mast cell activator. With this study we demonstrate that compound 48/80 also directly activates enteric neurons and visceral afferents. METHODOLOGY/PRINCIPAL FINDINGS: We used in vivo recordings from extrinsic intestinal afferents together with Ca(++ imaging from primary cultures of DRG and nodose neurons. Enteric neuronal activation was examined by Ca(++ and voltage sensitive dye imaging in isolated gut preparations and primary cultures of enteric neurons. Intraluminal application of compound 48/80 evoked marked afferent firing which desensitized on subsequent administration. In egg albumen-sensitized animals, intraluminal antigen evoked a similar pattern of afferent activation which also desensitized on subsequent exposure to antigen. In cross-desensitization experiments prior administration of compound 48/80 failed to influence the mast cell mediated response. Application of 1 and 10 µg/ml compound 48/80 evoked spike discharge and Ca(++ transients in enteric neurons. The same nerve activating effect was observed in primary cultures of DRG and nodose ganglion cells. Enteric neuron cultures were devoid of mast cells confirmed by negative staining for c-kit or toluidine blue. In addition, in cultured enteric neurons the excitatory action of compound 48/80 was preserved in the presence of histamine H(1 and H(2 antagonists. The mast cell stabilizer cromolyn attenuated compound 48/80 and nicotine evoked Ca(++ transients in mast cell-free enteric neuron cultures. CONCLUSIONS/SIGNIFICANCE: The results showed direct excitatory action of compound 48/80 on enteric neurons and visceral afferents. Therefore, functional changes measured in tissue or animal models may involve a mast cell independent effect of compound 48/80 and cromolyn.

  17. Degradation effects of the active region in UV-C light-emitting diodes

    Science.gov (United States)

    Glaab, Johannes; Haefke, Joscha; Ruschel, Jan; Brendel, Moritz; Rass, Jens; Kolbe, Tim; Knauer, Arne; Weyers, Markus; Einfeldt, Sven; Guttmann, Martin; Kuhn, Christian; Enslin, Johannes; Wernicke, Tim; Kneissl, Michael

    2018-03-01

    An extensive analysis of the degradation characteristics of AlGaN-based ultraviolet light-emitting diodes emitting around 265 nm is presented. The optical power of LEDs stressed at a constant dc current of 100 mA (current density = 67 A/cm2 and heatsink temperature = 20 °C) decreased to about 58% of its initial value after 250 h of operation. The origin of this degradation effect has been studied using capacitance-voltage and photocurrent spectroscopy measurements conducted before and after aging. The overall device capacitance decreased, which indicates a reduction of the net charges within the space-charge region of the pn-junction during operation. In parallel, the photocurrent at excitation energies between 3.8 eV and 4.5 eV and the photocurrent induced by band-to-band absorption in the quantum barriers at 5.25 eV increased during operation. The latter effect can be explained by a reduction of the donor concentration in the active region of the device. This effect could be attributed to the compensation of donors by the activation or diffusion of acceptors, such as magnesium dopants or group-III vacancies, in the pn-junction space-charge region. The results are consistent with the observed reduction in optical power since deep level acceptors can also act as non-radiative recombination centers.

  18. Low geometry counter for the absolute measurement of the activity of alpha-emitting sources

    International Nuclear Information System (INIS)

    Garcia-Torano, E.; Acena, M.L.

    1989-01-01

    A low-geometry counter is described which allows the absolute determination of the activity for alpha-emitting sources. A Si implanted detector is used to obtain the spectrum of the sample. Two samples are measured with this counter and a 2 π gridded ion chamber. The results an their uncertainties for both instruments are discussed. (Author)

  19. Secondary organic aerosol formation from a large number of reactive man-made organic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Derwent, Richard G., E-mail: r.derwent@btopenworld.com [rdscientific, Newbury, Berkshire (United Kingdom); Jenkin, Michael E. [Atmospheric Chemistry Services, Okehampton, Devon (United Kingdom); Utembe, Steven R.; Shallcross, Dudley E. [School of Chemistry, University of Bristol, Bristol (United Kingdom); Murrells, Tim P.; Passant, Neil R. [AEA Environment and Energy, Harwell International Business Centre, Oxon (United Kingdom)

    2010-07-15

    A photochemical trajectory model has been used to examine the relative propensities of a wide variety of volatile organic compounds (VOCs) emitted by human activities to form secondary organic aerosol (SOA) under one set of highly idealised conditions representing northwest Europe. This study applied a detailed speciated VOC emission inventory and the Master Chemical Mechanism version 3.1 (MCM v3.1) gas phase chemistry, coupled with an optimised representation of gas-aerosol absorptive partitioning of 365 oxygenated chemical reaction product species. In all, SOA formation was estimated from the atmospheric oxidation of 113 emitted VOCs. A number of aromatic compounds, together with some alkanes and terpenes, showed significant propensities to form SOA. When these propensities were folded into a detailed speciated emission inventory, 15 organic compounds together accounted for 97% of the SOA formation potential of UK man made VOC emissions and 30 emission source categories accounted for 87% of this potential. After road transport and the chemical industry, SOA formation was dominated by the solvents sector which accounted for 28% of the SOA formation potential.

  20. Polymer-coated vertical-cavity surface-emitting laser diode vapor sensor

    DEFF Research Database (Denmark)

    Ansbæk, Thor; Nielsen, Claus Højgaard; Larsen, Niels Bent

    2010-01-01

    We report a new method for monitoring vapor concentration of volatile organic compounds using a vertical-cavity surface-emitting laser (VCSEL). The VCSEL is coated with a polymer thin film on the top distributed Bragg reflector (DBR). The analyte absorption is transduced to the electrical domain ...

  1. Influence of co-deposited active layers on carrier transport and luminescent properties in organic light emitting diodes

    Energy Technology Data Exchange (ETDEWEB)

    Murata, Masaya; Yamamoto, Takayuki; Haishi, Motoki; Ohtani, Naoki [Department of Electronics, Doshisha University, Tatara-Miyakodani, Kyotanabe-shi, Kyoto (Japan); Ando, Taro [Central Research Laboratory, Hamamatsu Photonics, Hirakuchi, Hamakita-ku, Hamamatsu-shi, Shizuoka (Japan)

    2009-01-15

    We have investigated the influence of a co-deposited active layer in organic light-emitting diodes (OLEDs) on carrier transport and optical properties to improve radiative characteristics of OLEDs. The co-deposited layer consists of two organic materials; one is a hole transport material (TPD) and the other is an electron transport/emissive material (Alq3). We evaluated current-voltage characteristics and electroluminescence (EL) properties of various samples in which the thicknesses and compound ratios of the co-deposited layers are different. The results indicate that the devices consisting of TPD:Alq3 co-deposited layer sandwiched between TPD and Alq3 layers exhibit lower starting voltages for the light emission than the sample of simple TPD/Alq3 heterojunction structure. In addition, the starting voltage is independent of the thickness of TPD:Alq3 co-deposited layer. These samples have two interfaces at both surfaces of TPD:Alq3 co-deposited layer. Thus, we estimated the radiative recombination occurs at the interfaces. Nevertheless, we found that the radiative recombination occurs only at the interface of TPD:Alq3 co-deposited layer and Alq3 layer. (copyright 2009 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  2. Anti-cancer activity of compounds from Bauhinia strychnifolia stem.

    Science.gov (United States)

    Yuenyongsawad, Supreeya; Bunluepuech, Kingkan; Wattanapiromsakul, Chatchai; Tewtrakul, Supinya

    2013-11-25

    The stem and root of Bauhinia strychnifolia Craib (Fabaceae family) have been traditionally used in Thailand to treat fever, alcoholic toxication, allergy and cancer. An EtOH extract of Bauhinia strychnifolia showed good inhibitory activity against several cancer cell lines including HT-29, HeLa, MCF-7 and KB. As there has been no previous reports on chemical constituents of Bauhinia strychnifolia, this study is aimed to isolate the pure compounds with anti-cancer activity. Five pure compounds were isolated from EtOH extract of Bauhinia strychnifolia stem using silica gel, dianion HP-20 and sephadex LH-20 column chromatography and were tested for their cytotoxic effects against HT-29, HeLa, MCF-7 and KB cell lines using the Sulforhodamine B (SRB) assay. Among five compounds, 3,5,7,3',5'-pentahydroxyflavanonol-3-O-α-l-rhamnopyranoside (2) possessed very potent activity against KB (IC₅₀=0.00054μg/mL), HT-29 (IC₅₀=0.00217 μg/mL), MCF-7 (IC₅₀=0.0585 μg/mL) and HeLa cells (IC₅₀=0.0692 μg/mL). 3,5,7-Trihydroxychromone-3-O-α-l-rhamnopyranoside (3) also showed good activity against HT-29 (IC₅₀=0.02366 μg/mL), KB (IC₅₀=0.0412 μg/mL) and MCF-7 (IC₅₀=0.297 μg/mL), respectively. The activity of 2 (IC₅₀=0.00054 μg/mL) against KB cell was ten times higher than that of the positive control, Camptothecin (anti-cancer drug, IC₅₀=0.0057 μg/mL). All compounds did not show any cytotoxicity with normal cells at the concentration of 1 μg/mL. This is the first report of compounds 2 and 3 on anti-cancer activity and based on the anti-cancer activity of extracts and pure compounds isolated from Bauhinia strychnifolia stem, it might be suggested that this plant could be useful for treatment of cancer. © 2013 Elsevier Ireland Ltd. All rights reserved.

  3. Salt-Doped Polymer Light-Emitting Devices

    Science.gov (United States)

    Gautier, Bathilde

    Polymer Light-Emitting Electrochemical Cells (PLECs) are solid state devices based on the in situ electrochemical doping of the luminescent polymer and the formation of a p-n junction where light is emitted upon the application of a bias current or voltage. PLECs answer the drawbacks of polymer light-emitting diodes as they do not require an ultra-thin active layer nor are they reliant on low work function cathode materials that are air unstable. However, because of the dynamic nature of the doping, they suffer from slow response times and poor stability over time. Frozen-junction PLECs offer a solution to these drawbacks, yet they are impractical due to their sub-ambient operation temperature requirement. Our work presented henceforth aims to achieve room temperature frozen-junction PLECS. In order to do that we removed the ion solvating/transporting polymer from the active layer, resulting in a luminescent polymer combined solely with a salt sandwiched between an ITO electrode and an aluminum electrode. The resulting device was not expected to operate like a PLEC due to the absence of an ion-solvating and ion-transporting medium. However, we discovered that the polymer/salt devices could be activated by applying a large voltage bias, resulting in much higher current and luminance. More important, the activated state is quasi static. Devices based on the well-known orange-emitting polymer MEH-PPV displayed a luminance storage half-life of 150 hours when activated by forward bias (ITO biased positively with respect to the aluminum) and 200 hours when activated by reverse bias. More remarkable yet, devices based on a green co-polymer displayed no notable decay in current density or luminance even after being stored for 1200 hours at room temperature! PL imaging under UV excitation demonstrates the presence of doping. These devices are described herein along with an explanation of their operating mechanisms.

  4. Prediction and design of efficient exciplex emitters for high-efficiency, thermally activated delayed-fluorescence organic light-emitting diodes.

    Science.gov (United States)

    Liu, Xiao-Ke; Chen, Zhan; Zheng, Cai-Jun; Liu, Chuan-Lin; Lee, Chun-Sing; Li, Fan; Ou, Xue-Mei; Zhang, Xiao-Hong

    2015-04-08

    High-efficiency, thermally activated delayed-fluorescence organic light-emitting diodes based on exciplex emitters are demonstrated. The best device, based on a TAPC:DPTPCz emitter, shows a high external quantum efficiency of 15.4%. Strategies for predicting and designing efficient exciplex emitters are also provided. This approach allow prediction and design of efficient exciplex emitters for achieving high-efficiency organic light-emitting diodes, for future use in displays and lighting applications. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Effective anti-leishmanial activity of minimalist squaramide-based compounds.

    Science.gov (United States)

    Marín, Clotilde; Ximenis, Marta; Ramirez-Macías, Inmaculada; Rotger, Carmen; Urbanova, Kristina; Olmo, Francisco; Martín-Escolano, Rubén; Rosales, María José; Cañas, Rocio; Gutierrez-Sánchez, Ramón; Costa, Antonio; Sánchez-Moreno, Manuel

    2016-11-01

    In order to evaluate the in vitro leishmanicidal activity of N,N'-Squaramides derivatives, compounds that feature both hydrogen bond donor and acceptor groups and are capable of multiple interactions with complementary sites, against Leishmania infantum, Leishmania braziliensis and Leishmania donovani a series of 18compounds was prepared and assayed on extracellular and intracellular parasite forms. Infectivity and cytotoxicity tests were performed on J774.2 macrophage cells using meglumine antimoniate (Glucantime) as the reference drug. Changes in metabolite excretion by 1 H-NMR and the ultrastructural alterations occurring in the parasites treated using transmission electron microscopy (TEM), was analyzed. Compounds 1, 7, 11, 14 and 17 were the more active and less toxic. Infection rates showed that the order of effectiveness was 17 > 11 > 14 > 7 for both L. infantum and L. braziliensis and in the same way, the compound 1 for L. donovani. All these compounds have altered the typical structure of the promastigotes, glycosomes and mitochondria. These severe modifications by the compounds are the ultimate reasons for the alterations observed in the excretion products. The Squaramide 17 (3-(butylamino)-4-((3-(dimetilamino)propyl)(methyl)amino)cyclobut-3-en-1,2-dione) was clearly the most efficient of all compounds. The data appear to confirm that the severe modifications generated in organelles such as glycosomes or mitochondria by the compounds are the ultimate reasons for the alterations observed in the excretion products of all species. The activity, stability, low cost of starting materials, and straightforward synthesis make amino squaramides appropriate molecules for the development of an affordable anti-leishmanial agent. Copyright © 2016. Published by Elsevier Inc.

  6. Benzimidazoles: A biologically active compounds

    Directory of Open Access Journals (Sweden)

    Salahuddin

    2017-02-01

    Full Text Available Synthesis of commercially available benzimidazole involves condensation of o-phenylenediamine with formic acid. The most prominent benzimidazole compound in nature is N-riosyldimethylbenzimidazole, which serves as a axial ligand for cobalt in vitamin B12. The benzimidazole and its derivatives play a very important role as a therapeutic agent e.g. antiulcer and anthelmintic drugs. Apart from this the benzimidazole derivatives exhibit pharmacological activities such as antimicrobial, antiviral, anticancer, anti-inflammatory, analgesic, etc. The substituted benzimidazoles are summarized in this review to know about the chemistry as well as pharmacological activities.

  7. Antileishmanial activities of dihydrochalcones from piper elongatum and synthetic related compounds. Structural requirements for activity.

    Science.gov (United States)

    Hermoso, Alicia; Jiménez, Ignacio A; Mamani, Zulma A; Bazzocchi, Isabel L; Piñero, José E; Ravelo, Angel G; Valladares, Basilio

    2003-09-01

    Two dihydrochalcones (1 and 2) were isolated from Piper elongatum Vahl by activity-guided fractionation against extracellular promastigotes of Leishmania braziliensis in vitro. Their structures were elucidated by spectral analysis, including homonuclear and heteronuclear correlation NMR experiments. Derivatives 3-7 and 20 synthetic related compounds (8-27) were also assayed to establish the structural requirements for antileishmanial activity. Compounds 1-11 that proved to be more active that ketoconazol, used as positive control, were further assayed against promastigotes of Leishmania tropica and Leishmania infantum. Compounds 7 and 11, with a C(6)-C(3)-C(6) system, proved to be the most promising compounds, with IC(50) values of 2.98 and 3.65 microg/mL, respectively, and exhibited no toxic effect on macrophages (around 90% viability). Correlation between the molecular structures and antileishmanial activity is discussed in detail.

  8. Synthesis and anticonvulsant activity of certain chalcone based pyrazoline compounds

    Directory of Open Access Journals (Sweden)

    Sudhakara Rao Gerapati

    2015-09-01

    Full Text Available Convulsions are involuntary, violent, spasmodic and prolonged contractions of skeletal muscles. That means a patient may have epilepsy without convulsions and vice versa. Epilepsy is a common neurological abnormality affecting about 1% of the world population. The primary objectives of these synthesized compounds are to suppress seizures and provide neuroprotection by minimizing the effects from seizure attacks. Here some of the chalcones and chalcone based various pyrazolines were evaluated for anticonvulsant activity. Their structures have been elucidated on the basis of elemental analyses and spectroscopic studies (IR, 1H-NMR & Mass spectroscopy. A preliminary evaluation of the prepared compounds has indicated that some of them exhibit moderate to significant anticonvulsant activity compared to a diazepam standard1-3.  All compounds were tested for their anticonvulsant activity using maximal electroshock induced convulsions (MES in mice at a dose level of 4 mg/kg.b.w. The compounds  Ph1, Ph2 , Py2 ,Py3 and Py4 have shown  to  good anticonvulsant activity when doses are administered as 25mg/ kg.b.w  , reduced the phases of seizures severity and  found to be active and also  increased survival rate. Remaining compounds are less efficacious.

  9. Odour-active compounds in guava (Psidium guajava L. cv. Red Suprema).

    Science.gov (United States)

    Pino, Jorge A; Bent, Leandra

    2013-09-01

    Solid phase microextraction and simultaneous distillation-extraction combined with GC-FID, GC/MS, aroma extract dilution analysis and odour activity values were used to analyse volatile compounds from guava (Psidium guajava L. cv. Red Suprema) and to estimate the most odour-active compounds. The analysis led to the detection of 141 compounds, 121 of which were positively identified. The composition of guava fruit volatiles included 43 esters, 37 terpenes, 18 aldehydes, 16 alcohols, ten acids, six ketones, four furans and seven miscellaneous compounds. Seventeen odorants were considered as odour-active compounds, with (E)-β-ionone, ethyl hexanoate, ethyl butanoate, hexanal, (Z)-3-hexenal, hexyl acetate, (E)-2-hexenal and limonene contributing most to the typical guava aroma of this cultivar. © 2013 Society of Chemical Industry.

  10. ZnSe Light Emitting Diode Quantum Efficiency and Emission Characterization

    Directory of Open Access Journals (Sweden)

    Sahbudin U.K.

    2016-01-01

    Full Text Available ZnSe has demonstrated as a potential candidate in realizing advance LED in some appications for current and future works that utilize a cheaper preparation technique. Blue and white LEDs have been shown to spread across compound semiconductors. This II-VI compound semiconductor with a direct and wide band gap is used in the study which focused on a preparation and its characterization. The device is developed using a circular chip of ZnSe but only part of the active region is designed to allow shorter computation time. Analyses of the proposed LED are performed in an environment that allows optical transition and nonradiative recombination mechanisms. Voltage variation from 0 V to 1.5 V is maintained throughout the observation. The curent-voltage plot shows the p-n junction or diode behavior with central emissive layer. The two dimensions surface emission rate obtained indicates that voltage increment causes the emission concentration to become higher near the central pcontact. The LED efficiency is assessed in terms of internal quantum efficiency and emitting rate.

  11. Taste-active compounds in a traditional Italian food: 'lampascioni'.

    Science.gov (United States)

    Borgonovo, Gigliola; Caimi, Sara; Morini, Gabriella; Scaglioni, Leonardo; Bassoli, Angela

    2008-06-01

    Nature is a rich source of taste-active compounds, in particular of plant origin, many of which have unusual tastes. Many of these are found in traditional food, where spontaneous plants are used as ingredients. Some taste-active compounds were identified in the bulbs of Muscari comosum, a spontaneous plant belonging to the family of the Liliaceae, very common in the Mediterranean area, and used in traditional gastronomy (called 'lampascioni' in South Italy). The bulbs were extracted with a series of solvents of different polarity. The different fractions were submitted to a preliminary sensory evaluation, and the most interesting ones, characterized by a strong bitter taste and some chemestetic properties, were submitted to further purification and structural analysis. From the ethereal extract, several 3-benzyl-4-chromanones and one stilbene derivative were isolated. Pure compounds were examined for their taste activity by means of sensory evaluation, and proved to be responsible for the characteristic taste of this food. Some of these compounds have been synthesized de novo to confirm their structure.

  12. Aspartate and glutamate mimetic structures in biologically active compounds.

    Science.gov (United States)

    Stefanic, Peter; Dolenc, Marija Sollner

    2004-04-01

    Glutamate and aspartate are frequently recognized as key structural elements for the biological activity of natural peptides and synthetic compounds. The acidic side-chain functionality of both the amino acids provides the basis for the ionic interaction and subsequent molecular recognition by specific receptor sites that results in the regulation of physiological or pathophysiological processes in the organism. In the development of new biologically active compounds that possess the ability to modulate these processes, compounds offering the same type of interactions are being designed. Thus, using a peptidomimetic design approach, glutamate and aspartate mimetics are incorporated into the structure of final biologically active compounds. This review covers different bioisosteric replacements of carboxylic acid alone, as well as mimetics of the whole amino acid structure. Amino acid analogs presented include those with different distances between anionic moieties, and analogs with additional functional groups that result in conformational restriction or alternative interaction sites. The article also provides an overview of different cyclic structures, including various cycloalkane, bicyclic and heterocyclic analogs, that lead to conformational restriction. Higher di- and tripeptide mimetics in which carboxylic acid functionality is incorporated into larger molecules are also reviewed. In addition to the mimetic structures presented, emphasis in this article is placed on their steric and electronic properties. These mimetics constitute a useful pool of fragments in the design of new biologically active compounds, particularly in the field of RGD mimetics and excitatory amino acid agonists and antagonists.

  13. Volatile organic compounds emitted by filamentous fungi isolated from flooded homes after Hurricane Sandy show toxicity in a Drosophila bioassay.

    Science.gov (United States)

    Zhao, G; Yin, G; Inamdar, A A; Luo, J; Zhang, N; Yang, I; Buckley, B; Bennett, J W

    2017-05-01

    Superstorm Sandy provided an opportunity to study filamentous fungi (molds) associated with winter storm damage. We collected 36 morphologically distinct fungal isolates from flooded buildings. By combining traditional morphological and cultural characters with an analysis of ITS sequences (the fungal DNA barcode), we identified 24 fungal species that belong to eight genera: Penicillium (11 species), Fusarium (four species), Aspergillus (three species), Trichoderma (two species), and one species each of Metarhizium, Mucor, Pestalotiopsis, and Umbelopsis. Then, we used a Drosophila larval assay to assess possible toxicity of volatile organic compounds (VOCs) emitted by these molds. When cultured in a shared atmosphere with growing cultures of molds isolated after Hurricane Sandy, larval toxicity ranged from 15 to 80%. VOCs from Aspergillus niger 129B were the most toxic yielding 80% mortality to Drosophila after 12 days. The VOCs from Trichoderma longibrachiatum 117, Mucor racemosus 138a, and Metarhizium anisopliae 124 were relatively non-toxigenic. A preliminary analysis of VOCs was conducted using solid-phase microextraction-gas chromatography-mass spectrometry from two of the most toxic, two of the least toxic, and two species of intermediate toxicity. The more toxic molds produced higher concentrations of 1-octen-3-ol, 3-octanone, 3-octanol, 2-octen-1-ol, and 2-nonanone; while the less toxic molds produced more 3-methyl-1-butanol and 2-methyl-1-propanol, or an overall lower amount of volatiles. Our data support the hypothesis that at certain concentrations, some VOCs emitted by indoor molds are toxigenic. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. Volatile compounds from leaves of the African spider plant (Gynandropsis gynandra) with bioactivity against spider mite (Tetranychus urticae)

    DEFF Research Database (Denmark)

    Nyalala, Samuel Odeyo; Petersen, Mikael Agerlin; Grout, Brian William Wilson

    2013-01-01

    Previous studies have demonstrated that Gynandropsis gynandra emits acetonitrile as a foliar volatile from intact plants and isolated leaves, and that this compound is an effective spider mite repellent. This study has used gas chromatography–mass spectrometry to investigate volatile compounds...... emitted from homogenised G. gynandra leaves to evaluate their tissue acetonitrile content and to look for other compounds that might be exploited for the management of spider mites. Acetonitrile was absent from the homogenised tissues of five lines of G. gynandra, studied over two seasons. Thirteen...... volatile compounds were emitted by G. gynandra at significantly higher levels than mite-susceptible pot roses, including isothiocyanates, aldehydes, esters, alcohols and terpenes. Six representative compounds were selected to assess bioactivity. Spider mite populations were completely inactive after a 2¿h...

  15. Glucosidase inhibitory activity and antioxidant activity of flavonoid compound and triterpenoid compound from Agrimonia Pilosa Ledeb.

    Science.gov (United States)

    Liu, Xi; Zhu, Liancai; Tan, Jun; Zhou, Xuemei; Xiao, Ling; Yang, Xian; Wang, Bochu

    2014-01-10

    In Chinese traditional medicine, Agrimonia pilosa Ledeb (APL) exhibits great effect on treatment of type 2 diabetes mellitus (T2DM), however its mechanism is still unknown. Considering that T2DM are correlated with postprandial hyperglycemia and oxidative stress, we investigated the α-glucosidase inhibitory activity and the antioxidant activity of flavonoid compound (FC) and triterpenoid compound (TC) from APL. Entire plants of APL were extracted using 95% ethanol and 50% ethanol successively. The resulting extracts were partitioned and isolated by applying liquid chromatography using silica gel column and Sephadex LH 20 column to give FC and TC. The content of total flavonoids in FC and the content of total triterpenoids in TC were determined by using UV spectrophotometry. HPLC analysis was used to identify and quantify the monomeric compound in FC and TC. The α-glucosidase inhibitory activities were determined using the chromogenic method with p-nitrophenyl-α-D-glucopyranoside as substrate. Antioxidant activities were assessed through three kinds of radical scavenging assays (DPPH radical, ABTS radical and hydroxyl radical) & β-carotene-linoleic acid assay. The results indicate FC is abundant of quercitrin, and hyperoside, and TC is abundant of 1β, 2β, 3β, 19α-tetrahydroxy-12-en-28-oic acid (265.2 mg/g) and corosolic acid (100.9 mg/g). The FC & the TC have strong α-glucosidase inhibitory activities with IC50 of 8.72 μg/mL and 3.67 μg/mL, respectively. We find that FC show competitive inhibition against α-glucosidase, while the TC exhibits noncompetitive inhibition. Furthermore, The FC exhibits significant radical scavenging activity with the EC50 values of 7.73 μg/mL, 3.64 μg/mL and 5.90 μg/mL on DPPH radical, hydroxyl radical and ABTS radical, respectively. The FC also shows moderate anti-lipid peroxidation activity with the IC50 values of 41.77 μg/mL on inhibiting β-carotene bleaching. These results imply that the FC and the TC could be

  16. Fire emissions constrained by the synergistic use of formaldehyde and glyoxal SCIAMACHY columns in a two-compound inverse modelling framework

    Science.gov (United States)

    Stavrakou, T.; Muller, J.; de Smedt, I.; van Roozendael, M.; Vrekoussis, M.; Wittrock, F.; Richter, A.; Burrows, J.

    2008-12-01

    Formaldehyde (HCHO) and glyoxal (CHOCHO) are carbonyls formed in the oxidation of volatile organic compounds (VOCs) emitted by plants, anthropogenic activities, and biomass burning. They are also directly emitted by fires. Although this primary production represents only a small part of the global source for both species, yet it can be locally important during intense fire events. Simultaneous observations of formaldehyde and glyoxal retrieved from the SCIAMACHY satellite instrument in 2005 and provided by the BIRA/IASB and the Bremen group, respectively, are compared with the corresponding columns simulated with the IMAGESv2 global CTM. The chemical mechanism has been optimized with respect to HCHO and CHOCHO production from pyrogenically emitted NMVOCs, based on the Master Chemical Mechanism (MCM) and on an explicit profile for biomass burning emissions. Gas-to-particle conversion of glyoxal in clouds and in aqueous aerosols is considered in the model. In this study we provide top-down estimates for fire emissions of HCHO and CHOCHO precursors by performing a two- compound inversion of emissions using the adjoint of the IMAGES model. The pyrogenic fluxes are optimized at the model resolution. The two-compound inversion offers the advantage that the information gained from measurements of one species constrains the sources of both compounds, due to the existence of common precursors. In a first inversion, only the burnt biomass amounts are optimized. In subsequent simulations, the emission factors for key individual NMVOC compounds are also varied.

  17. Measurement of volatile organic compounds emitted in libraries and archives: an inferential indicator of paper decay?

    Directory of Open Access Journals (Sweden)

    Gibson Lorraine T

    2012-05-01

    Full Text Available Abstract Background A sampling campaign of indoor air was conducted to assess the typical concentration of indoor air pollutants in 8 National Libraries and Archives across the U.K. and Ireland. At each site, two locations were chosen that contained various objects in the collection (paper, parchment, microfilm, photographic material etc. and one location was chosen to act as a sampling reference location (placed in a corridor or entrance hallway. Results Of the locations surveyed, no measurable levels of sulfur dioxide were detected and low formaldehyde vapour (-3 was measured throughout. Acetic and formic acids were measured in all locations with, for the most part, higher acetic acid levels in areas with objects compared to reference locations. A large variety of volatile organic compounds (VOCs was measured in all locations, in variable concentrations, however furfural was the only VOC to be identified consistently at higher concentration in locations with paper-based collections, compared to those locations without objects. To cross-reference the sampling data with VOCs emitted directly from books, further studies were conducted to assess emissions from paper using solid phase microextraction (SPME fibres and a newly developed method of analysis; collection of VOCs onto a polydimethylsiloxane (PDMS elastomer strip. Conclusions In this study acetic acid and furfural levels were consistently higher in concentration when measured in locations which contained paper-based items. It is therefore suggested that both acetic acid and furfural (possibly also trimethylbenzenes, ethyltoluene, decane and camphor may be present in the indoor atmosphere as a result of cellulose degradation and together may act as an inferential non-invasive marker for the deterioration of paper. Direct VOC sampling was successfully achieved using SPME fibres and analytes found in the indoor air were also identified as emissive by-products from paper. Finally a new non

  18. Clusia hilariana and Eugenia uniflora as bioindicators of atmospheric pollutants emitted by an iron pelletizing factory in Brazil.

    Science.gov (United States)

    da Silva, Luzimar Campos; de Araújo, Talita Oliveira; Siqueira-Silva, Advanio Inácio; Pereira, Tiago Augusto Rodrigues; Castro, Letícia Nalon; Silva, Eduardo Chagas; Oliva, Marco Antonio; Azevedo, Aristéa Alves

    2017-12-01

    The objectives of this work were to evaluate if the pollution emitted by the pelletizing factory causes visual symptoms and/or anatomical changes in exposed Eugenia uniflora and Clusia hilariana, in active biomonitoring, at different distances from a pelletizing factory. We characterize the symptomatology, anatomical, and histochemistry alterations induced in the two species. There was no difference in the symptomatology in relation to the different distances of the emitting source. The foliar symptoms found in C. hilariana were chlorosis, necrosis, and foliar abscission and, in E. uniflora, were observed necrosis punctuais, purple spots in the leaves, and increase in the emission of new leaves completely purplish. The two species presented formation of a cicatrization tissue. E. uniflora presented reduction in the thickness of leaf. In C. hilariana, it was visualized hyperplasia of the cells and the adaxial epidermis did not appear collapsed due to thick cuticle and cuticular flanges. Leaves of C. hilariana showed positive staining for iron, protein, starch, and phenolic compounds. E. uniflora showed positive staining for total phenolic compounds and starch. Micromorphologically, there was accumulation of particulate matter on the leaf surface, obstruction of the stomata, and scaling of the epicuticular wax in both species. It was concluded that the visual and anatomical symptoms were efficient in the diagnosis of the stress factor. C. hilariana and E. uniflora showed to be good bioindicators of the atmospheric pollutants emitted by the pelletizing factory.

  19. Identification and Profiling of Active Compounds from Golden Apple Snail’s Egg Pigments

    Directory of Open Access Journals (Sweden)

    Asadatun Abdullah

    2017-08-01

    Full Text Available Golden apple snail (Pomacea canaliculata has been known as rice corps pest due to high adaptability and reproductive power. Utilization of Pomacea canaliculata’s eggs as raw materials in the food and health industry is one of the efforts to eradicate the pest snail. This study was aimed to identify the active compounds contained in the extract pigments of Pomacea canaliculata’s eggs. The methods of this study were extraction of pigments using acetone and methanol, analyzing the active compound (secondary metabolite qualitatively, TLC to determine pigment components and LC-MS/MS to identify active compounds semi quantitatively. The results showed that active compounds in the methanol extract contain 11 carotenoid pigments of xanthophyl group, two carotenoid pigments of carotene group, and 2 active compounds in nonpigmented form, whereas the acetone extract contain 11 pigmentcarotenoids of xanthophyl group and 2 compounds active in non-pigment form.

  20. Isolation and Antimicrobial Activity of Flavonoid Compounds from Mahagony Seeds (Swietenia macrophylla, King)

    Science.gov (United States)

    Mursiti, S.; Supartono

    2017-02-01

    Flavonoid is one of the secondary metabolites compounds in mahogany seeds. Mahogany seeds can be used as an antimicrobial. This study aims to determine the antimicrobial activity of flavonoid compounds from mahogany seeds against Escherichia coli (E.coli) and Bacillus cereus (B.cereus). Isolation of flavonoid compounds done step by step. First, the maceration using n-hexane, then with methanol. The methanol extract was dissolved in ethyl acetate and aquadest, then separated. Ethyl acetate extract evaporated Flavonoid compounds were. The testing of antimicrobial activity of flavonoid compounds using the absorption method. The results showed that the antimicrobial activity of flavonoid compounds from mahogany seeds shows the inhibitory activity and provide clear zone against bacteria E.coli with value Inhibitory Regional Diameter 18.50 mm respectively, and 14.50 mm to the bacteria. Based on the results of the study, it can be concluded that flavonoid compounds from mahogany seeds have antimicrobial activity against E.coli and B.cereus.

  1. Tunable blue organic light emitting diode based on aluminum calixarene supramolecular complex

    Science.gov (United States)

    Legnani, C.; Reyes, R.; Cremona, M.; Bagatin, I. A.; Toma, H. E.

    2004-07-01

    In this letter, the results of supramolecular organic light emitting diodes using a calix[4] arene complex thin film as emitter and electron transporting layer are presented. The devices were grown onto glass substrates coated with indium-tin-oxide layer and aluminum thick (150nm) cathode. By applying a dc voltage between the device electrodes in forward bias condition, a blue light emission in the active area of the device was observed. It was found that the electroluminescent emission peak can be tuned between 470 and 510nm changing the applied voltage bias from 4.3 to 5.4V. The observed tunable emission can be associated with an energy transfer from the calixarene compound.

  2. THE ANTIBACTERIAL ACTIVITY OF WATER APPLE LEAVES ACTIVE COMPOUND (Syzygium zeylanicum AGAINST Escherichia coli AND Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    - Hamidah

    2017-07-01

    Full Text Available Escherichia coli is one of the bacteria that cause infections in the human digestive tract such as diarrhea, while Staphylococcus aureus is one of the bacteria that cause infections in the skin injury such as boils and pimples. This study used Syzygium zeylanicum leaves because it has potential as a antibacterial because it contains active compounds. This study aimed was determine the antibacterial activity of the fraction and the active compound in Syzygium zeylanicum leaves against Escherichia coli and Staphylococcus aureus. Research conducted on November 2015 to January 2016. The method used in this research were extraction by maceration, fractionation by liquid fractionation, antibacterial activity test, and determination of minimum inhibitory concentration with the diffusion method and isolation of active compounds by column chromatography method. The bacteria used in this test are Escherichia coli and Staphylococcus aureus. Data are presented in tabular form based on the average value of the inhibition diameter and deviation standard. The results of this research showed the water methanol active fraction against the bacteria that used in this test. The methanol water fraction had obtained one antibacterial compound in bottle 1,3,5 which shows the value of tannin Rf 0,416. The minimum inhibitory concentration of water methanol of water apple leaves is 1000 µg/mL for Escherichia coli and 500 µg/mL for  Staphylococcus aureus. The minimum  inhibitory concentration of the active  compound  to  Escherichia  coli  and  Staphylococcus  aureus  in  500  µg/mL.  The fraction and the active compound of water apple leaves have an antibacterial activity with Escherichia coli and Staphylococcus aureus and the active compound is tannin.

  3. Developmental toxicity of thyroid-active compounds in a zebrafish embryotoxicity test

    NARCIS (Netherlands)

    Jomaa, B.; Hermsen, S.A.B.; Kessels, M.Y.; Berg, van den J.H.J.; Peijenburg, A.C.M.; Aarts, J.M.M.J.G.; Piersma, A.H.; Rietjens, I.

    2014-01-01

    Zebrafish embryos were exposed to concentration ranges of selected thyroid-active model compounds in order to assess the applicability of zebrafish-based developmental scoring systems within an alternative testing strategy to detect the developmental toxicity of thyroid-active compounds. Model

  4. Highly efficient exciplex organic light-emitting diodes using thermally activated delayed fluorescent emitters as donor and acceptor materials

    Science.gov (United States)

    Jeon, Sang Kyu; Yook, Kyoung Soo; Lee, Jun Yeob

    2016-06-01

    Highly efficient exciplex type organic light-emitting diodes were developed using thermally activated delayed fluorescent emitters as donors and acceptors of an exciplex. Blue emitting bis[4-(9,9-dimethyl-9,10-dihydroacridine)phenyl]sulfone (DMAC-DPS) was a donor and 9,9‧-(5-(4,6-diphenyl-1,3,5-triazin-2-yl)-1,3-phenylene)bis(9H-carbazole) (DDCzTrz) and 9,9‧,9″-(5-(4,6-diphenyl-1,3,5-triazin-2-yl)benzene-1,2,3-triyl)tris(9H-carbazole) (TCzTrz) were acceptor materials. The exciplexes of DMAC-DPS:TCzTrz and DMAC-DPS:DDCzTrz resulted in high photoluminescence quantum yield and high quantum efficiency in the green exciplex organic light-emitting diodes. High quantum efficiencies of 13.4% and 15.3% were obtained in the DMAC-DPS:DDCzTrz and DMAC-DPS:TCzTrz exciplex devices.

  5. Relationship structure-antioxidant activity of hindered phenolic compounds

    Directory of Open Access Journals (Sweden)

    Weng, X. C.

    2014-12-01

    Full Text Available The relationship between the structure and the antioxidant activity of 21 hindered phenolic compounds was investigated by Rancimat and DPPH· tests. 3-tert-butyl-5-methylbenzene-1,2-diol is the strongest antioxidant in the Rancimat test but not in the DPPH· test because its two hydroxyl groups have very strong steric synergy. 2,6-Ditert-butyl-4-hydroxy-methylphenol exhibits a strong antioxidant activity as 2,6-ditertbutyl- 4-methoxyphenol does in lard. 2,6-Ditert-butyl-4- hydroxy-methylphenol also exhibits stronger activity than 2-tert-butyl-4- methoxyphenol. The methylene of 2,6-ditert-butyl-4-hydroxy-methylphenol can provide a hydrogen atom to active free radicals like a phenolic hydroxyl group does because it is greatly activated by both the aromatic ring and hydroxyl group. Five factors affect the antioxidant activities of the phenolic compounds: how stable the phenolic compound free radicals are after providing hydrogen atoms; how many hy drogen atoms each of the phenolic compounds can provide; how fast the phenolic compounds provide hydrogen atoms; how easily the phenolic compound free radicals can combine with more active free radicals, and whether or not a new antioxidant can form after the phenolic compound provides hydrogen atoms.La relación entre estructura y la actividad antioxidante de 21 compuestos fenólicos con impedimentos estéricos fue investigado mediante ensayos con Rancimat y DPPH·. El 3-terc-butil-5-metilbenceno-1,2-diol es el antioxidante más potente en los ensayos mediante Rancimat pero no mediante ensayos con DPPH·, porque sus dos grupos hidroxilo tienen una fuerte sinergia estérica. El 2,6-Di-terc-butil-4-hidroxi-metil-fenol mostró una actividad antioxidante tan fuerte como el 2,6-di-ter-butil-4-metoxifenol en ensayos con manteca de cerdo. El 2,6-di-terc-butil-4-hidroxi-metilfenol también mostró una actividad más fuerte que el 2-terc-butil-4-metoxifenol. El grupo metileno del 2,6-di-ter-butil-4-hidroxi

  6. Volatile molecular markers of VOO Thermo-oxidation: Effect of heating processes, macronutrients composition, and olive ripeness on the new emitted aldehydic compounds.

    Science.gov (United States)

    Oueslati, Imen; Manaï, Hédia; Madrigal-Martínez, Mónica; Martínez-Cañas, Manuel A; Sánchez-Casas, Jacinto; Zarrouk, Mokhtar; Flamini, Guido

    2018-04-01

    Heating operation has been applied to Chétoui extra-virgin olive oils (EVOOs) extracted from fruits with several ripening stages (RS). The studied samples, were subjected to microwave and conventional heating. Results showed that heated VOOs after 2.5 h and 7 min of conventional and microwave heating, respectively, gave rise to a drastically decrease of LOX products and allowed the detection of toxic new formed aldehydic volatiles (alkanal: nonanal, alkenals: (Z)-2-heptenal and (E)-2-decenal, and alkadienals: (E.E)-2.4-decadienal), which can be used as markers of VOO degradation. Their abundance in the VOO headspaces depends on their boiling points, the rate of their possible degradation to yield other compounds, on the heating processes and on the rate of macronutrients. The emission rate of the new synthesized volatiles during heating processes was mainly attributed to enzymatic oxidation of some fatty acids. Hexanal, (Z)-2-heptenal, (E)-2-octenal, (E)-2-nonenal, (E,E) and (E,Z)-2,4-decadienal, and (E,E)-2,4-nonadienal, derived from linoleic acid, and heptanol, octanal, nonanal, decanal, (E) and (Z)-2-decenal, (E)-2-undecenal, and (E,E)-2,4-nonadienal, are emitted after degradation of oleic acid. During thermo-oxidation, the ECN 44 (LLO, and OLnO), and the ECN 46 (OLO, and PLO + SLL) compounds decreased, whereas, the ECN 48 (OOO, and PPO), and the ECN 50 (SOO) compounds increased when temperature and heating time increased. The several variations of the studied biochemical compounds depend to the heating processes. Ripening stage of olive fruits can be used as a tool to monitor the emission rate of the aldehydic volatiles, but cannot be used for a chemometric discrimination. Copyright © 2018 Elsevier Ltd. All rights reserved.

  7. Hybrid white organic light-emitting diodes combining blue-fluorescent polymer and red phosphorescent Pt(II) complexes as active layer

    Energy Technology Data Exchange (ETDEWEB)

    Germino, Jose Carlos; Faleiros, Marcelo Meira; Moraes, Emmanuel Santos; Atvars, Teresa Dib Zambon, E-mail: kakagermino@hotmail.com [Universidade Estadual de Campinas (UNICAMP), SP (Brazil); Domingues, Raquel Aparecida [Universidade Federal de Sao Paulo (UNIFESP), SP (Brazil); Quites, Fernando Junior [Universidade Federal de Mato Grosso (UFMT), Cuiaba, MT (Brazil); Freitas, Jilian Nei de [Centro de Tecnologia da Informacao Renato Archer, Campinas, SP (Brazil)

    2016-07-01

    Full text: In this work we proposed a PFO composite with two salicylidene based Pt(II) coordination compounds, the [Pt(salophen)] and [Pt(sal-3,4-ben)] (red emitters), as emissive layer (EML) for Organic Light-emitting Diodes (OLEDs), combining a blue-fluorescent polymer (PFO) with red-phosphorescent Pt(II) coordination complexes in order to obtain an efficient white electroluminescent EML for WOLEDs application. Firstly, [Pt(salophen)] and [Pt(sal-3,4-ben)] were synthesized, purified and characterized by single crystal X-ray diffraction, yielding their respective expected molecular structures. The photoluminescence properties of the devices were evaluated by steady-state (electronic absorption and emission spectroscopies) and transient (fluorescence decays and TRES) measurements. It was observed the presence of non-radiative energy transfer processes between the PFO derivative and Pt(II) complexes. Posteriorly, the Pt(II) complexes were blended with PVK at 1% mol:mol ratio and OLEDs were made, leading to red-emitting devices with high color purity for the two coordination compounds. However, the two devices present low current efficiency values. In order to improve the electroluminescence properties of Pt(II) complexes PhOLEDs, PVK host was substituted by PFO at 0.5, 1.0 and 2.5% mol:mol ratios of complex and it was observed a great improvement of their optical-electronic properties in terms of luminance, voltage, current density and current efficiency in comparison to PVK composites or pure PFO devices. At 2.5% concentration, predominant bands of Pt(II) complexes were observed at low and high voltages. For the other concentrations, a different behavior was observed: the emission bands and device color were function of applied electrical field, exhibiting a red color at lower voltages (5 to 9V) and the PFO characteristic emission between 9 and 13V, leading to a white light emission at 13V. The best results were obtained for [Pt(sal-3,4-ben)] coordination compound

  8. Data-Driven Derivation of an "Informer Compound Set" for Improved Selection of Active Compounds in High-Throughput Screening.

    Science.gov (United States)

    Paricharak, Shardul; IJzerman, Adriaan P; Jenkins, Jeremy L; Bender, Andreas; Nigsch, Florian

    2016-09-26

    Despite the usefulness of high-throughput screening (HTS) in drug discovery, for some systems, low assay throughput or high screening cost can prohibit the screening of large numbers of compounds. In such cases, iterative cycles of screening involving active learning (AL) are employed, creating the need for smaller "informer sets" that can be routinely screened to build predictive models for selecting compounds from the screening collection for follow-up screens. Here, we present a data-driven derivation of an informer compound set with improved predictivity of active compounds in HTS, and we validate its benefit over randomly selected training sets on 46 PubChem assays comprising at least 300,000 compounds and covering a wide range of assay biology. The informer compound set showed improvement in BEDROC(α = 100), PRAUC, and ROCAUC values averaged over all assays of 0.024, 0.014, and 0.016, respectively, compared to randomly selected training sets, all with paired t-test p-values agnostic fashion. This approach led to a consistent improvement in hit rates in follow-up screens without compromising scaffold retrieval. The informer set is adjustable in size depending on the number of compounds one intends to screen, as performance gains are realized for sets with more than 3,000 compounds, and this set is therefore applicable to a variety of situations. Finally, our results indicate that random sampling may not adequately cover descriptor space, drawing attention to the importance of the composition of the training set for predicting actives.

  9. Assessment of A Simple Compound-Saving Method To Study Insecticidal Activity of Natural Extracts and Pure Compounds Against Mosquito Larvae.

    Science.gov (United States)

    Falkowski, Michaël; Jahn-Oyac, Arnaud; Ferrero, Emma; Issaly, Jean; Eparvier, Véronique; Girod, Romain; Rodrigues, Alice M S; Stien, Didier; Houël, Emeline; Dusfour, Isabelle

    2016-12-01

    Research on natural insecticides has intensified with the spread of resistance to chemicals among insects, particularly disease vectors. To evaluate compounds, the World Health Organization (WHO) has published standardized procedures. However, those may be excessively compound-consuming when it comes to assessing the activity of natural extracts and pure compounds isolated in limited amount. As part of our work on the discovery of new mosquito larvicides from Amazonian plants, we developed a compound-saving assay in 5-ml glass tubes instead of WHO larval 100-ml cups. Comparing activity of synthetic and natural chemicals validated the glass tube assay. Raw data, lethal doses that kill 50% (LD 50 ) and 90% (LD 90 ) at 24 and 48 h, were highly correlated (0.68 natural extracts and molecules, identifying active compounds using 10 times less material than in the WHO protocol.

  10. Measurement of loss rates of organic compounds in snow using in situ experiments and isotopically labelled compounds

    Directory of Open Access Journals (Sweden)

    Erika von Schneidemesser

    2012-07-01

    Full Text Available Organic molecular marker compounds are widely used to identify emissions from anthropogenic and biogenic air pollution sources in atmospheric samples and in deposition. Specific organic compounds have been detected in polar regions, but their fate after deposition to snow is poorly characterized. Within this context, a series of exposure experiments were carried out to observe the post-depositional processing of organic compounds under real-world conditions in snow on the surface of the Greenland Ice Sheet, at the Summit research station. Snow was prepared from water spiked with isotopically labelled organic compounds, representative of typical molecular marker compounds emitted from anthropogenic activities. Reaction rate constants and reaction order were determined based on a decrease in concentration to a stable, non-zero, threshold concentration. Fluoranthene-d10, docosane-d46, hexadecanoic acid-d31, docosanoic acid-d43 and azelaic acid-d14 were estimated to have first order loss rates within surface snow with reaction rate constants of 0.068, 0.040, 0.070, 0.067 and 0.047 h−1, respectively. No loss of heptadecane-d36 was observed. Overall, these results suggest that organic contaminants are archived in polar snow, although significant post-depositional losses of specific organic compounds occur. This has implications for the environmental fate of organic contaminants, as well as for ice-core studies that seek to use organic molecular markers to infer past atmospheric loadings, and source emissions.

  11. Thermally Activated Delayed Fluorescence Emitters for Deep Blue Organic Light Emitting Diodes: A Review of Recent Advances

    Directory of Open Access Journals (Sweden)

    Thanh-Tuân Bui

    2018-03-01

    Full Text Available Organic light-emitting diodes offer attractive perspectives for the next generation display and lighting technologies. The potential is huge and the list of potential applications is almost endless. So far, blue emitters still suffer from noticeably inferior electroluminescence performances in terms of efficiency, lifespan, color quality, and charge injection/transport when compared to that of the other colors. Emitting materials matching the NTSC standard blue of coordinates (0.14, 0.08 are extremely rare and still constitutes the focus of numerous academic and industrial researches. In this context, we review herein the recent developments on highly emissive deep-blue thermally activated delayed fluorescence emitters that constitute the third-generation electroluminescent materials.

  12. Anti-human rhinoviral activity of polybromocatechol compounds isolated from the rhodophyta, Neorhodomela aculeata.

    Science.gov (United States)

    Park, Soon-Hye; Song, Jae-Hyoung; Kim, Taejung; Shin, Woon-Seob; Park, Gab Man; Lee, Seokjoon; Kim, Young-Joo; Choi, Pilju; Kim, Heejin; Kim, Hui-Seong; Kwon, Dur-Han; Choi, Hwa Jung; Ham, Jungyeob

    2012-10-01

    An extract of the red alga, Neorhodomela aculeata, exhibited antiviral activity against human rhinoviruses. Bioassay-guided purification was performed to yield six compounds, which were subsequently identified as lanosol (1) and five polybromocatechols (2-6) by spectroscopic methods, including 1D and 2D NMR and mass spectrometric analyses. Structurally, all of these compounds, except compound 5, contain one or two 2,3-dibromo-4,5-dihydroxyphenyl moieties. In a biological activity assay, compound 1 was found to possess antiviral activity with a 50% inhibitory concentration (IC₅₀) of 2.50 μg/mL against HRV2. Compound 3 showed anti-HRV2 activity, with an IC₅₀ of 7.11 μg/mL, and anti-HRV3 activity, with an IC₅₀ of 4.69 μg/mL, without demonstrable cytotoxicity at a concentration of 20 μg/mL. Collectively, the results suggest that compounds 1 and 3 are candidates for novel therapeutics against two different groups of human rhinovirus.

  13. Antibacterial and antifungal activity of sulfur-containing compounds from Petiveria alliacea L.

    Science.gov (United States)

    Kim, Seokwon; Kubec, Roman; Musah, Rabi A

    2006-03-08

    A total of 18 organosulfur compounds originating from Petiveria alliacea L. roots have been tested for their antibacterial and antifungal activities. These represent compounds occurring in fresh homogenates as well as those present in various macerates, extracts and other preparations made from Petiveria alliacea. Of the compounds assayed, the thiosulfinates, trisulfides and benzylsulfinic acid were observed to be the most active, with the benzyl-containing thiosulfinates exhibiting the broadest spectrum of antimicrobial activity. The effect of plant sample preparation conditions on the antimicrobial activity of the extract is discussed.

  14. Activity concentrations and mean annual effective dose from gamma-emitting radionuclides in the Lebanese diet

    International Nuclear Information System (INIS)

    Nasreddine, L.; Hwalla, N.; El Samad, O.; Baydoun, R.; Hamze, M.; Parent-Massin, D.

    2008-01-01

    Since the primary factor contributing to the internal effective dose in the human organism is contaminated food, the control of radionuclides in food represents the most important means of protection. This study was conducted to determine the levels of the dietary exposure of the Lebanese population to gamma-emitting radioisotopes. The activity concentrations of gamma-emitting radioisotopes have been measured in food samples that represent the market basket of an adult urban population in Lebanon. The artificial radionuclide 137 Cs was measured above detection limits in only fish, meat and milk-based deserts. The most abundant natural radionuclide was 40 K (31-121 Bq kg -1 ), with the highest content in fish and meat samples. The annual mean effective dose contributed by 40 K in the reference typical diet was estimated equal to 186 μSv y -1 , a value reasonably consistent with findings reported by several other countries. (authors)

  15. Biologically Active Macrocyclic Compounds – from Natural Products to Diversity‐Oriented Synthesis

    DEFF Research Database (Denmark)

    Madsen, Charlotte Marie; Clausen, Mads Hartvig

    2011-01-01

    Macrocyclic compounds are attractive targets when searching for molecules with biological activity. The interest in this compound class is increasing, which has led to a variety of methods for tackling the difficult macrocyclization step in their synthesis. This microreview highlights some recent...... developments in the synthesis of macrocycles, with an emphasis on chemistry developed to generate libraries of putative biologically active compounds....

  16. Advances in the development of AMPK-activating compounds.

    Science.gov (United States)

    Sriwijitkamol, Apiradee; Musi, Nicolas

    2008-10-01

    AMP-activated protein kinase (AMPK) is an energy sensing enzyme that controls glucose and lipid metabolism. This review summarizes the present data on AMPK as a pharmacologic target for the treatment of metabolic disorders. The mechanisms governing AMPK activity and how this enzyme controls different metabolic pathways are reviewed briefly, and details about the effect that AMPK activators have on glucose metabolism are provided. Evidence obtained using the AMPK-activating compound 5-aminoimidazole-4-carboxamide-1-β-d-ribofuranoside (AICAR) suggests that AMPK promotes glucose transport into skeletal muscles and that this enzyme inhibits hepatic glucose production. AICAR also induces fatty acid oxidation in muscle and inhibits cholesterol synthesis in the liver. The metabolic effects of AICAR on glucose and lipid metabolism indicate that AMPK may be a good pharmacologic target for the treatment of type 2 diabetes and hypercholesterolemia. Novel AMPK-specific compounds are allowing researchers to examine whether this enzyme is a useful pharmacologic target for the treatment of human disease and whether chronic activation of AMPK will be safe.

  17. ANTIBACTERIAL COMPOUNDS ACTIVITY OF MANGROVE LEAF EXTRACT RHIZOPHORA MUCRONATA ON AEROMONAS HYDROPHYLA

    Directory of Open Access Journals (Sweden)

    Panjaitan M.A.P.

    2018-01-01

    Full Text Available Pathogenic bacterial infections such as A.hydrophyla in fish cultivation are common problems. A.hydrophyla belongs to a group of bacteria resistant to more than one type of antibiotic. This study aims to determine the antibacterial activity of R.mucronata mangrove leaf extract and to identify potential antibacterial compounds. The research procedure includes extraction, compound refinement, phytochemical test, antibacterial activity test, and KBM-KHM Test. The results show that the antibacterial ability possessed by R.mucronata leaves crude extract increased after the extract was purified utilizing separating funnel. The lowest concentration of methanol fraction extract capable of inhibiting A.hydrophyla (KHM growth was at 8.25±0.39 ppm, while the lowest concentration of A.hydrophyla was 32.99±1.56 ppm. Bioactive compounds contained in methanol R.mucronata leaves extract are alkaloid compounds, flavonoids, and tannins. Out of the three compounds detected, antibacterial activity is thought to be derived from flavonoid and tannin compounds.

  18. Carbonaceous species emitted from handheld two-stroke engines

    Science.gov (United States)

    Volckens, John; Olson, David A.; Hays, Michael D.

    Small, handheld two-stroke engines used for lawn and garden work (e.g., string trimmers, leaf blowers, etc.) can emit a variety of potentially toxic carbonaceous air pollutants. Yet, the emissions effluents from these machines go largely uncharacterized, constraining the proper development of human exposure estimates, emissions inventories, and climate and air quality models. This study samples and evaluates chemical pollutant emissions from the dynamometer testing of six small, handheld spark-ignition engines—model years 1998-2002. Four oil-gas blends were tested in each engine in duplicate. Emissions of carbon dioxide, carbon monoxide, and gas-phase hydrocarbons were predominant, and the PM emitted was organic matter primarily. An ANOVA model determined that engine type and control tier contributed significantly to emissions variations across all identified compound classes; whereas fuel blend was an insignificant variable accounting for engines were generally intermediate in magnitude compared with other gasoline-powered engines, numerous compounds traditionally viewed as motor vehicle markers are also present in small engine emissions in similar relative proportions. Given that small, handheld two-stroke engines used for lawn and garden work account for 5-10% of total US emissions of CO, CO 2, NO x, HC, and PM 2.5, source apportionment models and human exposure studies need to consider the effect of these small engines on ambient concentrations in air polluted environments.

  19. Anti-Human Rhinoviral Activity of Polybromocatechol Compounds Isolated from the Rhodophyta, Neorhodomela aculeata

    Directory of Open Access Journals (Sweden)

    Hui-Seong Kim

    2012-10-01

    Full Text Available An extract of the red alga, Neorhodomela aculeata, exhibited antiviral activity against human rhinoviruses. Bioassay-guided purification was performed to yield six compounds, which were subsequently identified as lanosol (1 and five polybromocatechols (2–6 by spectroscopic methods, including 1D and 2D NMR and mass spectrometric analyses. Structurally, all of these compounds, except compound 5, contain one or two 2,3-dibromo-4,5-dihydroxyphenyl moieties. In a biological activity assay, compound 1 was found to possess antiviral activity with a 50% inhibitory concentration (IC50 of 2.50 μg/mL against HRV2. Compound 3 showed anti-HRV2 activity, with an IC50 of 7.11 μg/mL, and anti-HRV3 activity, with an IC50 of 4.69 μg/mL, without demonstrable cytotoxicity at a concentration of 20 μg/mL. Collectively, the results suggest that compounds 1 and 3 are candidates for novel therapeutics against two different groups of human rhinovirus.

  20. Activity-Guided Isolation of Antioxidant Compounds from Andrographis stenophylla Leaf

    Directory of Open Access Journals (Sweden)

    Neelaveni Thangavel

    2010-01-01

    Full Text Available The antioxidant potency of various extracts of Andrographis stenophylla leaf was evaluated in vitro using ferric thiocyanate method. Reductive ability and free radical scavenging activity of the extracts were also investigated. Amounts of phenolic compounds in each of the extracts were determined using Folin-Ciocalteau reagent and compared to observe the correlation between antioxidant activities and total phenolic content. Methanol extract exhibited maximum antioxidant activity and was found to contain 2% of total phenolic compounds. Methanol extract was subjected to column chromatographic separation over silica gel G using ethyl acetate: formic acid: acetic acid: water. Fractions thus obtained were screened for their antioxidant activity. Among the eleven fractions screened, fraction C was more active than the standard butylated hydroxyanisole. Fraction C on further fractionation with n-butanol: acetic acid: water afforded two flavanoids namely acacetine and isosakuranetine. Fraction A was also shown to possess good antioxidant activity which was developed using TLC and indicated the presence of a terpenoid, Andrographolide. The structures of the isolated compounds were confirmed by UV, IR, MS, 1H and 13C NMR spectral data. This is the first report wherein Andrographolide, Acacetine and Isosakuranetine are isolated from Andrographis stenophylla leaf.

  1. Online air analysis of reduced sulfur compounds at a swine facility

    Science.gov (United States)

    Reduced sulfur compounds are emitted from waste management handling and can be important in odor production and atmospheric chemistry. Data on the emissions of these compounds have been obtained using off-line sampling and analysis methods, but on-line methods providing information on temporal chang...

  2. Use of thermal desorption gas chromatography-olfactometry/mass spectrometry for the comparison of identified and unidentified odor active compounds emitted from building products containing linseed oil

    DEFF Research Database (Denmark)

    Clausen, P. A.; Knudsen, Henrik Nellemose; Larsen, K.

    2008-01-01

    The emission of odor active volatile organic compounds (VOCs) from a floor oil based on linseed oil, the linseed oil itself and a low-odor linseed oil was investigated by thermal desorption gas chromatography combined with olfactometry and mass spectrometry (TD-GC-O/MS). The oils were applied...... to filters and conditioned in the micro emission cell, FLEC, for 1-3 days at ambient temperature, an air exchange rate of 26.9 h-1 and a 30% relative humidity. These conditions resulted in dynamic headspace concentrations and composition of the odor active VOCs that may be similar to real indoor setting...

  3. Cryptic antifungal compounds active by synergism with polyene antibiotics.

    Science.gov (United States)

    Kinoshita, Hiroshi; Yoshioka, Mariko; Ihara, Fumio; Nihira, Takuya

    2016-04-01

    The majority of antifungal compounds reported so far target the cell wall or cell membrane of fungi, suggesting that other types of antibiotics cannot exert their activity because they cannot penetrate into the cells. Therefore, if the permeability of the cell membrane could be enhanced, many antibiotics might be found to have antifungal activity. We here used the polyene antibiotic nystatin, which binds to ergosterol and forms pores at the cell membrane, to enhance the cellular permeability. In the presence of nystatin, many culture extracts from entomopathogenic fungi displayed antifungal activity. Among all the active extracts, two active components were purified and identified as helvolic acid and terramide A. Because the minimum inhibitory concentration of either compound was reduced four-fold in the presence of nystatin, it can be concluded that this screening method is useful for detecting novel antifungal activity. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  4. Nanofibrous matrixes with biologically active hydroxybenzophenazine pyrazolone compound for cancer theranostics

    International Nuclear Information System (INIS)

    Kandhasamy, Subramani; Ramanathan, Giriprasath; Muthukumar, Thangavelu; Thyagarajan, SitaLakshmi; Umamaheshwari, Narayanan; Santhanakrishnan, V P; Sivagnanam, Uma Tiruchirapalli; Perumal, Paramasivan Thirumalai

    2017-01-01

    The nanomaterial with the novel biologically active compounds has been actively investigated for application in cancer research. Substantial use of nanofibrous scaffold for cancer research with potentially bioactive compounds through electrospinning has not been fully explored. Here, we describe the series of fabrication of nanofibrous scaffold loaded with novel potential biologically active hydroxybenzo[a]phenazine pyrazol-5(4H)-one derivatives were designed, synthesized by a simple one-pot, two step four component condensation based on Michael type addition reaction of lawsone, benzene-1,2-diamine, aromatic aldehydes and 3-methyl-1-phenyl-1H-pyrazol-5(4H)-one as the substrates. The heterogeneous solid state catalyst (Fe (III) Y-Zeolite) could effectively catalyze the reaction to obtain the product with high yield and short reaction time. The synthesized compounds (5a–5p) were analyzed by NMR, FTIR and HRMS analysis. Compound 5c was confirmed by single crystal XRD studies. All the compounds were biologically evaluated for their potential inhibitory effect on anticancer (MCF-7, Hep-2) and microbial (MRSA, MTCC 201 and FRCA) activities. Among the compounds 5i exhibited the highest levels of inhibitory activity against both MCF-7, Hep-2 cell lines. Furthermore, the compound 5i (BPP) was evaluated for DNA fragmentation, flow cytometry studies and cytotoxicity against MCF-7, Hep-2 and NIH 3T3 fibroblast cell lines. In addition, molecular docking (PDB ID: (1T46)) studies were performed to predict the binding affinity of ligand with receptor. Moreover, the synthesized BPP compound was loaded in to the PHB-PCL nanofibrous scaffold to check the cytotoxicity against the MCF-7, Hep-2 and NIH 3T3 fibroblast cell lines. The in vitro apoptotic potential of the PHB-PCL-BPP nanofibrous scaffold was assessed against MCF-7, Hep-2 cancerous cells and fibroblast cells at 12, 24 and 48 h respectively. The nanofibrous scaffold with BPP can induce apoptosis and also suppress the

  5. Nanofibrous matrixes with biologically active hydroxybenzophenazine pyrazolone compound for cancer theranostics

    Energy Technology Data Exchange (ETDEWEB)

    Kandhasamy, Subramani [Organic Chemistry Division, CSIR-Central Leather Research Institute, Adyar, Chennai 600020, Tamilnadu (India); Ramanathan, Giriprasath [Bioproducts Lab, CSIR-Central Leather Research Institute, Chennai 600020, Tamilnadu (India); Muthukumar, Thangavelu [Department of Clinical and Experimental Medicine (IKE), Division of Neuro and Inflammation Sciences (NIV), Linkoping University (Sweden); Thyagarajan, SitaLakshmi [Bioproducts Lab, CSIR-Central Leather Research Institute, Chennai 600020, Tamilnadu (India); Umamaheshwari, Narayanan [Organic Chemistry Division, CSIR-Central Leather Research Institute, Adyar, Chennai 600020, Tamilnadu (India); Santhanakrishnan, V P [Department of Plant Biotechnology, TNAU, Coimbatore, Tamilnadu (India); Sivagnanam, Uma Tiruchirapalli, E-mail: suma67@gmail.com [Bioproducts Lab, CSIR-Central Leather Research Institute, Chennai 600020, Tamilnadu (India); Perumal, Paramasivan Thirumalai, E-mail: ptperumal@gmail.com [Organic Chemistry Division, CSIR-Central Leather Research Institute, Adyar, Chennai 600020, Tamilnadu (India)

    2017-05-01

    The nanomaterial with the novel biologically active compounds has been actively investigated for application in cancer research. Substantial use of nanofibrous scaffold for cancer research with potentially bioactive compounds through electrospinning has not been fully explored. Here, we describe the series of fabrication of nanofibrous scaffold loaded with novel potential biologically active hydroxybenzo[a]phenazine pyrazol-5(4H)-one derivatives were designed, synthesized by a simple one-pot, two step four component condensation based on Michael type addition reaction of lawsone, benzene-1,2-diamine, aromatic aldehydes and 3-methyl-1-phenyl-1H-pyrazol-5(4H)-one as the substrates. The heterogeneous solid state catalyst (Fe (III) Y-Zeolite) could effectively catalyze the reaction to obtain the product with high yield and short reaction time. The synthesized compounds (5a–5p) were analyzed by NMR, FTIR and HRMS analysis. Compound 5c was confirmed by single crystal XRD studies. All the compounds were biologically evaluated for their potential inhibitory effect on anticancer (MCF-7, Hep-2) and microbial (MRSA, MTCC 201 and FRCA) activities. Among the compounds 5i exhibited the highest levels of inhibitory activity against both MCF-7, Hep-2 cell lines. Furthermore, the compound 5i (BPP) was evaluated for DNA fragmentation, flow cytometry studies and cytotoxicity against MCF-7, Hep-2 and NIH 3T3 fibroblast cell lines. In addition, molecular docking (PDB ID: (1T46)) studies were performed to predict the binding affinity of ligand with receptor. Moreover, the synthesized BPP compound was loaded in to the PHB-PCL nanofibrous scaffold to check the cytotoxicity against the MCF-7, Hep-2 and NIH 3T3 fibroblast cell lines. The in vitro apoptotic potential of the PHB-PCL-BPP nanofibrous scaffold was assessed against MCF-7, Hep-2 cancerous cells and fibroblast cells at 12, 24 and 48 h respectively. The nanofibrous scaffold with BPP can induce apoptosis and also suppress the

  6. Origin of a counterintuitive yellow light-emitting electrochemical cell based on a blue-emitting heteroleptic copper(i) complex.

    Science.gov (United States)

    Weber, Michael D; Garino, Claudio; Volpi, Giorgio; Casamassa, Enrico; Milanesio, Marco; Barolo, Claudia; Costa, Rubén D

    2016-06-07

    This work provides the synthesis, structural characterization, electrochemical and photophysical features, as well as the application in light-emitting electrochemical cells (LECs) of a novel heteroleptic copper(i) complex - [Cu(impy)(POP)][PF6], where impy is 3-(2-methoxyphenyl)-1-(pyridine-2-yl)imidazo[1,5-a]pyridine and POP is bis{2-(diphenylphosphanyl)phenyl}ether. This compound shows blue photoluminescence (PL, λ = 450 nm) in solution and solid-state and excellent redox stability. Despite these excellent features, the electroluminescence (EL) response is located at ∼550 nm. Although the EL spectrum of LECs is typically red-shifted compared to the PL of the electroluminescent material, a shift of ca. 100 nm represents the largest one reported in LECs. To date, the large shift phenomena have been attributed to (i) a change in the nature of the lowest emitting state due to a concentration effect of the films, (ii) a reversible substitution of the ligands due to the weak coordination to the Cu(i), and (iii) a change in the distribution of the excited states due to polarization effects. After having discarded these along with others like the irreversible degradation of the emitter during device fabrication and/or under operation conditions, driving conditions, active layer composition, and changes in the excited states under different external electrical stimuli, we attribute the origin of this unexpected shift to a lack of a thermally activated delayed fluorescence (TADF) process due to the solely ligand-centered character of the excited states. As such, the lack of a charge transfer character in the excited states leads to a blue-fluorescence and yellow-phosphorescence photo- and electro-responses, respectively. This corroborates recent studies focused on the design of TADF for heteroleptic copper(i) complexes. Overall, this work is a clear insight into the design of new copper(i) complexes towards the preparation of blue LECs, which are still unexplored.

  7. Synthesis, Characterization, and Antimicrobial Activities of Coordination Compounds of Aspartic Acid

    Directory of Open Access Journals (Sweden)

    T. O. Aiyelabola

    2016-01-01

    Full Text Available Coordination compounds of aspartic acid were synthesized in basic and acidic media, with metal ligand M : L stoichiometric ratio 1 : 2. The complexes were characterized using infrared, electronic and magnetic susceptibility measurements, and mass spectrometry. Antimicrobial activity of the compounds was determined against three Gram-positive and three Gram-negative bacteria and one fungus. The results obtained indicated that the availability of donor atoms used for coordination was a function of the pH of the solution in which the reaction was carried out. This resulted in varying geometrical structures for the complexes. The compounds exhibited a broad spectrum of activity and in some cases better activity than the standard.

  8. Activating AMP-activated protein kinase by an α1 selective activator compound 13 attenuates dexamethasone-induced osteoblast cell death

    International Nuclear Information System (INIS)

    Guo, Shiguang; Mao, Li; Ji, Feng; Wang, Shouguo; Xie, Yue; Fei, Haodong; Wang, Xiao-dong

    2016-01-01

    Excessive glucocorticoid (GC) usage may lead to non-traumatic femoral head osteonecrosis. Dexamethasone (Dex) exerts cytotoxic effect to cultured osteoblasts. Here, we investigated the potential activity of Compound 13 (C13), a novel α1 selective AMP-activated protein kinase (AMPK) activator, against the process. Our data revealed that C13 pretreatment significantly attenuated Dex-induced apoptosis and necrosis in both osteoblastic-like MC3T3-E1 cells and primary murine osteoblasts. AMPK activation mediated C13′ cytoprotective effect in osteoblasts. The AMPK inhibitor Compound C, shRNA-mediated knockdown of AMPKα1, or dominant negative mutation of AMPKα1 (T172A) almost abolished C13-induced AMPK activation and its pro-survival effect in osteoblasts. On the other hand, forced AMPK activation by adding AMPK activator A-769662 or exogenous expression a constitutively-active (ca) AMPKα1 (T172D) mimicked C13's actions and inhibited Dex-induced osteoblast cell death. Meanwhile, A-769662 or ca-AMPKα1 almost nullified C13's activity in osteoblast. Further studies showed that C13 activated AMPK-dependent nicotinamide adenine dinucleotide phosphate (NADPH) pathway to inhibit Dex-induced reactive oxygen species (ROS) production in MC3T3-E1 cells and primary murine osteoblasts. Such effects by C13 were almost reversed by Compound C or AMPKα1 depletion/mutation. Together, these results suggest that C13 alleviates Dex-induced osteoblast cell death via activating AMPK signaling pathway. - Highlights: • Compound 13 (C13) attenuates dexamethasone (Dex)-induced osteoblast cell death. • C13-induced cytoprotective effect against Dex in osteoblasts requires AMPK activation. • Forced AMPK activation protects osteoblasts from Dex, nullifying C13's activities. • C13 increases NADPH activity and inhibits Dex-induced oxidative stress in osteoblasts.

  9. Activating AMP-activated protein kinase by an α1 selective activator compound 13 attenuates dexamethasone-induced osteoblast cell death

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Shiguang [Department of Intensive Care Unit, Huai' an First People' s Hospital, Nanjing Medical University, Huai' an (China); Mao, Li [Department of Endocrinology, Huai' an First People' s Hospital, Nanjing Medical University, Huai' an (China); Ji, Feng, E-mail: huaiaifengjidr@163.com [Department of Orthopedics, Huai' an First People' s Hospital, Nanjing Medical University, Huai' an (China); Wang, Shouguo; Xie, Yue; Fei, Haodong [Department of Orthopedics, Huai' an First People' s Hospital, Nanjing Medical University, Huai' an (China); Wang, Xiao-dong, E-mail: xiaodongwangsz@163.com [The Center of Diagnosis and Treatment for Children' s Bone Diseases, The Children' s Hospital Affiliated to Soochow University, Suzhou (China)

    2016-03-18

    Excessive glucocorticoid (GC) usage may lead to non-traumatic femoral head osteonecrosis. Dexamethasone (Dex) exerts cytotoxic effect to cultured osteoblasts. Here, we investigated the potential activity of Compound 13 (C13), a novel α1 selective AMP-activated protein kinase (AMPK) activator, against the process. Our data revealed that C13 pretreatment significantly attenuated Dex-induced apoptosis and necrosis in both osteoblastic-like MC3T3-E1 cells and primary murine osteoblasts. AMPK activation mediated C13′ cytoprotective effect in osteoblasts. The AMPK inhibitor Compound C, shRNA-mediated knockdown of AMPKα1, or dominant negative mutation of AMPKα1 (T172A) almost abolished C13-induced AMPK activation and its pro-survival effect in osteoblasts. On the other hand, forced AMPK activation by adding AMPK activator A-769662 or exogenous expression a constitutively-active (ca) AMPKα1 (T172D) mimicked C13's actions and inhibited Dex-induced osteoblast cell death. Meanwhile, A-769662 or ca-AMPKα1 almost nullified C13's activity in osteoblast. Further studies showed that C13 activated AMPK-dependent nicotinamide adenine dinucleotide phosphate (NADPH) pathway to inhibit Dex-induced reactive oxygen species (ROS) production in MC3T3-E1 cells and primary murine osteoblasts. Such effects by C13 were almost reversed by Compound C or AMPKα1 depletion/mutation. Together, these results suggest that C13 alleviates Dex-induced osteoblast cell death via activating AMPK signaling pathway. - Highlights: • Compound 13 (C13) attenuates dexamethasone (Dex)-induced osteoblast cell death. • C13-induced cytoprotective effect against Dex in osteoblasts requires AMPK activation. • Forced AMPK activation protects osteoblasts from Dex, nullifying C13's activities. • C13 increases NADPH activity and inhibits Dex-induced oxidative stress in osteoblasts.

  10. Antibacterial Activity of Phenolic Compounds Against the Phytopathogen Xylella fastidiosa

    OpenAIRE

    Maddox, Christina E.; Laur, Lisa M.; Tian, Li

    2010-01-01

    Xylella fastidiosa is a pathogenic bacterium that causes diseases in many crop species, which leads to considerable economic loss. Phenolic compounds (a group of secondary metabolites) are widely distributed in plants and have shown to possess antimicrobial properties. The anti-Xylella activity of 12 phenolic compounds, representing phenolic acid, coumarin, stilbene and flavonoid, was evaluated using an in vitro agar dilution assay. Overall, these phenolic compounds were effective in inhibiti...

  11. Enhanced optical power of GaN-based light-emitting diode with compound photonic crystals by multiple-exposure nanosphere-lens lithography

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yonghui; Wei, Tongbo, E-mail: tbwei@semi.ac.cn; Xiong, Zhuo; Shang, Liang; Tian, Yingdong; Zhao, Yun; Zhou, Pengyu; Wang, Junxi; Li, Jinmin [Semiconductor Lighting Technology Research and Development Center, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083 (China)

    2014-07-07

    The light-emitting diodes (LEDs) with single, twin, triple, and quadruple photonic crystals (PCs) on p-GaN are fabricated by multiple-exposure nanosphere-lens lithography (MENLL) process utilizing the focusing behavior of polystyrene spheres. Such a technique is easy and economical for use in fabricating compound nano-patterns. The optimized tilted angle is decided to be 26.6° through mathematic calculation to try to avoid the overlay of patterns. The results of scanning electron microscopy and simulations reveal that the pattern produced by MENLL is a combination of multiple ovals. Compared to planar-LED, the light output power of LEDs with single, twin, triple, and quadruple PCs is increased by 14.78%, 36.03%, 53.68%, and 44.85% under a drive current 350 mA, respectively. Furthermore, all PC-structures result in no degradation of the electrical properties. The stimulated results indicate that the highest light extraction efficiency of LED with the clover-shape triple PC is due to the largest scattering effect on propagation of light from GaN into air.

  12. Volatile Organic Compounds (VOCs) in the Ambient Air Of Concentration Unit of Sar-Cheshmeh Copper Complex

    International Nuclear Information System (INIS)

    Faghihi-Zrandi, A.; Akhgar, M. R.

    2016-01-01

    Air pollutants including gases, vapors and particles, are emitted from different sources. Volatile organic compounds are the most important pollutants in the ambient air of industries. The present study was carried out to identify and measurement of volatile organic compounds in concentration unit of Sar-Cheshmeh Copper Complex. In this study, sampling of the volatile organic compounds was done by using activated charcoal tube. To identify and measure these compounds gas chromatography/mass spectroscopy were used. Thirteen volatile organic compounds were identified in the ambient air of concentration unit. Among these compounds, the mean value and maximum concentration of isopropyl alcohol and nonane were 255, 640 μg/m3 and 1577, 14400 μg/m3, respectively. By using SPSS software and independent sample t- test, showed that there were no significant difference between mean value concentration of isopropyl alcohol and nonane in the ambient air and TLV values of these compounds (isopropyl alcohol; 200 ppm and nonane; 200 ppm) (P >0.05).

  13. Antiplasmodial activity of some phenolic compounds from ...

    African Journals Online (AJOL)

    Background: Plasmodium falciparum, one of the causative agents of malaria, has high adaptability through mutation and is resistant to many types of anti-malarial drugs. This study presents an in vitro assessment of the antiplasmodial activity of some phenolic compounds isolated from plants of the genus Allanblackia.

  14. Synthesis and characterization of yellow and green light emitting novel polymers containing carbazole and electroactive moieties

    International Nuclear Information System (INIS)

    Aydın, Aysel; Kaya, İsmet

    2012-01-01

    Graphical abstract: The homopolymer of 1,5-bis(3,6-di(thiophen-3-yl)-9H-carbazol-9-yl)pentane and the copolymer with EDOT of 1,2-bis(2-(3,6-di(thiophen-3-yl)-9H-carbazol-9-yl)ethoxy)ethane were synthesized via electrochemical reaction on indium tin oxide (ITO)-coated glass plate. The obtained polymeric compounds were investigated as fluorescence properties in solution form. The synthesized polymers showed good fluorescence property indicating tunable light emission with green and yellow colors. This shows that these polymers could be used in production of new polymeric light emitting diodes (PLED)s for green and yellow color emissions. - Abstract: The compounds 1,5-bis(3,6-di(thiophen-3-yl)-9H-carbazol-9-yl)pentane (B1) and 1,2-bis(2-(3,6-di(thiophen-3-yl)-9H-carbazol-9-yl)ethoxy)ethane (B2) were synthesized via Ullmann and Suzuki couplings. Additionally, the homopolymers and copolymers of these compounds with 3,4-ethylenedioxythiophene (EDOT) and thiophene (Th) were synthesized and coated onto an ITO-glass surface via electrochemical oxidative polymerization. The spectroelectrochemical and electrochromic properties of these compounds were also investigated. The switching ability of these polymers was measured as the percent transmittance (%T) at their point of maximum contrast. The solid state electrical conductivities of the polymeric films coated onto the ITO-glass surface were measured via the four point probe technique using an electrometer. The compounds were characterized by FT-IR and NMR, and their thermal stabilities were determined via TG measurements. Fluorescence measurements were performed using DMSO solutions, and the synthesized polymers emitted both green and yellow colors based on the tuning of the excitation wavelength, which indicates that these polymers could be used to produce new polymeric light emitting diodes (PLEDs) with green and yellow emissions.

  15. Recent developments in white light emitting diodes

    Science.gov (United States)

    Lohe, P. P.; Nandanwar, D. V.; Belsare, P. D.; Moharil, S. V.

    2018-05-01

    In the recent years solid state lighting based on LEDs has revolutionized lighting technology. LEDs have many advantages over the conventional lighting based on fluorescent and incandescent lamps such as mercury free, high conversion efficiency of electrical energy into light, long lifetime reliability and ability to use with many types of devices. LEDs have emerged as a new potentially revolutionary technology that could save up to half of energy used for lighting applications. White LEDs would be the most important light source in the future, so much so that this aspect had been highlighted by the Nobel committee during the award of 2014 Nobel Prize for Physics. Recent advancement in the fabrication of GaN chip capable of emitting in blue and near UV region paved way for fabrication of white LED lamps. Mainly there are two approaches used for preparing white emitting solid state lamp. In the first approach blue light (λ=450 nm) emitted from the InGaN LED chip is partially absorbed by the YAG:Ce3+ phosphor coated on it and re-emitted as yellow fluorescence. A white light can be generated by the combination of blue + yellow emission bands. These lamps are already available. But they are suffering from major drawback that their Colour Rendering Index (CRI) is low. In the second approach, white LEDs are made by coating near ultraviolet emitting (360 to 410nm) LED with a mixture of high efficiency red, green and blue emitting phosphors, analogous to the fluorescent lamp. This method yields lamps with better color rendition. Addition of a yellow emitting phosphor improves CRI further. However conversion efficiency is compromised to some extent. Further the cost of near UV emitting chip is very high compared to blue emitting chips. Thus cost and light output wise, near UV chips are much inferior to blue chips. Recently some rare earth activated oxynitrides, silicates, fluorides have emerged as an important family of luminescent materials for white LED application

  16. A study on volatile organic compounds emitted by in-vitro lung cancer cultured cells using gas sensor array and SPME-GCMS.

    Science.gov (United States)

    Thriumani, Reena; Zakaria, Ammar; Hashim, Yumi Zuhanis Has-Yun; Jeffree, Amanina Iymia; Helmy, Khaled Mohamed; Kamarudin, Latifah Munirah; Omar, Mohammad Iqbal; Shakaff, Ali Yeon Md; Adom, Abdul Hamid; Persaud, Krishna C

    2018-04-02

    Volatile organic compounds (VOCs) emitted from exhaled breath from human bodies have been proven to be a useful source of information for early lung cancer diagnosis. To date, there are still arguable information on the production and origin of significant VOCs of cancer cells. Thus, this study aims to conduct in-vitro experiments involving related cell lines to verify the capability of VOCs in providing information of the cells. The performances of e-nose technology with different statistical methods to determine the best classifier were conducted and discussed. The gas sensor study has been complemented using solid phase micro-extraction-gas chromatography mass spectrometry. For this purpose, the lung cancer cells (A549 and Calu-3) and control cell lines, breast cancer cell (MCF7) and non-cancerous lung cell (WI38VA13) were cultured in growth medium. This study successfully provided a list of possible volatile organic compounds that can be specific biomarkers for lung cancer, even at the 24th hour of cell growth. Also, the Linear Discriminant Analysis-based One versus All-Support Vector Machine classifier, is able to produce high performance in distinguishing lung cancer from breast cancer cells and normal lung cells. The findings in this work conclude that the specific VOC released from the cancer cells can act as the odour signature and potentially to be used as non-invasive screening of lung cancer using gas array sensor devices.

  17. Radiosensitization of Escherichia coli and Salmonella typhi in presence of active compounds

    International Nuclear Information System (INIS)

    Lacroix, M.; Chiasson, F.; Borsa, J.; Ouattara, B.

    2004-01-01

    The radiosensitization of Escherichia coli and Salmonella typhi in ground beef was evaluated in the presence of 18 active compounds. Medium fat ground beef (23% fat) was inoculated with E. coli or S. typhi and each active compound was added separately at various concentrations. For E. coli, the most efficient compounds were trans-cinnamaldehyde, thymol and thyme. For S. typhi, the most efficient compounds was trans-cinnamaldehyde, carvacrol and thymol. The addition of tetrasodium pyrophosphate, carvacrol and ascorbic acid had no effect on the irradiation sensitivity of E. coli. For S. typhi, only ascorbic acid had no effect

  18. Radiosensitization of Escherichia coli and Salmonella typhi in presence of active compounds

    Energy Technology Data Exchange (ETDEWEB)

    Lacroix, M. E-mail: monique.lacroix@inrs-iaf.uquebec.ca; Chiasson, F.; Borsa, J.; Ouattara, B

    2004-10-01

    The radiosensitization of Escherichia coli and Salmonella typhi in ground beef was evaluated in the presence of 18 active compounds. Medium fat ground beef (23% fat) was inoculated with E. coli or S. typhi and each active compound was added separately at various concentrations. For E. coli, the most efficient compounds were trans-cinnamaldehyde, thymol and thyme. For S. typhi, the most efficient compounds was trans-cinnamaldehyde, carvacrol and thymol. The addition of tetrasodium pyrophosphate, carvacrol and ascorbic acid had no effect on the irradiation sensitivity of E. coli. For S. typhi, only ascorbic acid had no effect.

  19. Effect of vanadium compounds on acid phosphatase activity

    OpenAIRE

    Vescina, Cecilia M.; Sálice, Viviana C.; Cortizo, Ana María; Etcheverry, Susana B.

    1996-01-01

    The direct effect of different vanadium compounds on acid phosphatase (ACP) activity was investigated. Vanadate and vanadyl but not pervanadate inhibited the wheat germ ACP activity. These vanadium derivatives did not alter the fibroblast Swiss 3T3 soluble fraction ACP activity. Using inhibitors of tyrosine phosphatases (PTPases), the wheat germ ACP was partially characterized as a PTPase. This study suggests that the inhibitory ability of different vanadium derivatives to modulate ACP activi...

  20. Primary emissions and chemical oxidation of volatile organic compounds emitted from laboratory biomass burning sources during the 2016 FIREX FireLab campaign: measurements from a H3O+ chemical ionization mass spectrometer

    Science.gov (United States)

    Coggon, M. M.; Warneke, C.; Koss, A.; Sekimoto, K.; Yuan, B.; Lim, C. Y.; Hagan, D. H.; Kroll, J. H.; Cappa, C. D.; Gilman, J.; Lerner, B. M.; Jimenez, J. L.; Yokelson, R. J.; Roberts, J. M.; De Gouw, J. A.

    2017-12-01

    Non-methane organic gases (NMOG) emitted by biomass burning constitute a large source of reactive carbon in the atmosphere. Once emitted, these compounds may undergo series of reactions with the OH radical and nitrogen oxides to form secondary organic aerosol (SOA), ozone, or other health-impacting products. The complex emission profile and strong variability of biomass burning NMOG play an important, yet understudied, role in the variability of air quality outcomes such as SOA and ozone. In this study, we summarize measurements of biomass burning volatile organic compounds (VOCs) conducted using a H3O+ chemical ionization mass spectrometer (H3O+-CIMS) during the 2016 FIREX laboratory campaign in Missoula, MT. Specifically, we will present data demonstrating the chemical evolution of biomass burning VOCs artificially aged in a field-deployable photooxidation chamber and an oxidation flow reactor. More than 50 OH-oxidation experiments were conducted with biomass types representing a range of North American fuels. Across many fuel types, VOCs with high SOA and ozone formation potential, such as aromatics and furans, were observed to quickly react with the OH radical while oxidized species were generated. We compare the calculated OH reactivity of the primary emissions to the calculated OH reactivity used in many photochemical models and highlight areas requiring additional research in order to improve model/measurement comparisons.

  1. Biologically Active Compounds of Plant Foods: Prospective Impact ...

    African Journals Online (AJOL)

    On the other hand, other biologically active compounds impair health by ... of essential elements through different mechanisms and giving astringent taste, odor, ... The health benefits of selected substances from Ethiopian food crops need to ...

  2. Synthesis of Some Novel Thiadiazole Derivative Compounds and Screening Their Antidepressant-Like Activities

    Directory of Open Access Journals (Sweden)

    Nafiz Öncü Can

    2018-03-01

    Full Text Available Novel thiadiazole derivatives were synthesized through the reaction of acetylated 2-aminothiadiazole and piperazine derivatives. The chemical structures of the compounds were clarified by Infrared Spectroscopy (IR, 1H Nuclear Magnetic Resonance Spectroscopy (1H-NMR, 13C Nuclear Magnetic Resonance Spectroscopy (13C-NMR and Electronspray Ionisation Mass Spectroscopy (ESI-MS spectroscopic methods. Antidepressant-like activities were evaluated by the tail-suspension (TST and modified forced swimming (MFST methods. Besides, possible influence of the test compounds on motor activities of the animals were examined by activity cage tests. In the TST, administration of the compounds 2c, 2d, 2e, 2f, 2g and 2h significantly decreased the immobility time of mice regarding the control values. Further, in the MFST, the same compounds reduced the total number of immobility behaviors while increasing swimming performance. However, no change was observed in the total number of climbing behaviors. These data suggested that compounds 2c, 2d, 2e, 2f, 2g and 2h possess notable antidepressant-like activities. Reference drug fluoxetine (10 mg/kg was also exhibited its antidepressant activity, as expected. No significant difference was seen between the locomotor activity values of the test groups signifying that observed antidepressant-like activities are specific. Theoretical calculation of absorption, distribution, metabolism, excretion (ADME properties for the obtained compounds were performed and obtained data supported the antidepressant-like potential of these novel thiadiazole derivatives.

  3. Role of ozone and granular activated carbon in the removal of mutagenic compounds.

    Science.gov (United States)

    Bourbigot, M M; Hascoet, M C; Levi, Y; Erb, F; Pommery, N

    1986-01-01

    The identification of certain organic compounds in drinking water has led water treatment specialists to be increasingly concerned about the eventual risks of such pollutants to the health of consumers. Our experiments focused on the role of ozone and granular activated carbon in removing mutagenic compounds and precursors that become toxic after chlorination. We found that if a sufficient dose of ozone is applied, its use does not lead to the creation of mutagenic compounds in drinking water and can even eliminate the initial mutagenicity of the water. The formation of new mutagenic compounds seems to be induced by ozonation that is too weak, although these mutagens can be removed by GAC filtration. Ozone used with activated carbon can be one of the best means for eliminating the compounds contributing to the mutagenicity of water. A combined treatment of ozone and activated carbon also decreases the chlorine consumption of the treated water and consequently reduces the formation of chlorinated organic compounds. PMID:3816720

  4. Plant compounds insecticide activity against Coleoptera pests of stored products

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, Marcio Dionizio; Picanco, Marcelo Coutinho; Guedes, Raul Narciso Carvalho; Campos, Mateus Ribeiro de; Silva, Gerson Adriano; Martins, Julio Claudio [Universidade Federal de Vicosa (UFV), MG (Brazil). Dept. de Biologia Animal; br, picanco@ufv; br, guedes@ufv; br, mateusc3@yahoo com; br, agronomiasilva@yahoo com

    2007-07-15

    The objective of this work was to screen plants with insecticide activity, in order to isolate, identify and assess the bioactivity of insecticide compounds present in these plants, against Coleoptera pests of stored products: Oryzaephilus surinamensis L. (Silvanidae), Rhyzopertha dominica F. (Bostrichidae) and Sitophilus zeamais Mots. (Curculionidae). The plant species used were: basil (Ocimum selloi Benth.), rue (Ruta graveolens L.), lion's ear (Leonotis nepetifolia (L.) R.Br.), jimson weed (Datura stramonium L.), baleeira herb (Cordia verbenacea L.), mint (Mentha piperita L.), wild balsam apple (Mormodica charantia L.), and billy goat weed or mentrasto (Ageratum conyzoides L.). The insecticide activity of hexane and ethanol extracts from those plants on R. dominica was evaluated. Among them, only hexane extract of A. conyzoides showed insecticide activity; the hexane extract of this species was successively fractionated by silica gel column chromatography, for isolation and purification of the active compounds. Compounds 5,6,7,8,3',4',5'-heptamethoxyflavone; 5,6,7,8,3'-pentamethoxy-4',5'-methilenedioxyflavone and coumarin were identified. However, only coumarin showed insecticide activity against three insect pests (LD{sub 50} from 2.72 to 39.71 mg g{sup -1} a.i.). The increasing order of insects susceptibility to coumarin was R. dominica, S. zeamais and O. surinamensis. (author)

  5. Plant compounds insecticide activity against Coleoptera pests of stored products

    International Nuclear Information System (INIS)

    Moreira, Marcio Dionizio; Picanco, Marcelo Coutinho; Guedes, Raul Narciso Carvalho; Campos, Mateus Ribeiro de; Silva, Gerson Adriano; Martins, Julio Claudio; julioufv@yahoo.com.br

    2007-01-01

    The objective of this work was to screen plants with insecticide activity, in order to isolate, identify and assess the bioactivity of insecticide compounds present in these plants, against Coleoptera pests of stored products: Oryzaephilus surinamensis L. (Silvanidae), Rhyzopertha dominica F. (Bostrichidae) and Sitophilus zeamais Mots. (Curculionidae). The plant species used were: basil (Ocimum selloi Benth.), rue (Ruta graveolens L.), lion's ear (Leonotis nepetifolia (L.) R.Br.), jimson weed (Datura stramonium L.), baleeira herb (Cordia verbenacea L.), mint (Mentha piperita L.), wild balsam apple (Mormodica charantia L.), and billy goat weed or mentrasto (Ageratum conyzoides L.). The insecticide activity of hexane and ethanol extracts from those plants on R. dominica was evaluated. Among them, only hexane extract of A. conyzoides showed insecticide activity; the hexane extract of this species was successively fractionated by silica gel column chromatography, for isolation and purification of the active compounds. Compounds 5,6,7,8,3',4',5'-heptamethoxyflavone; 5,6,7,8,3'-pentamethoxy-4',5'-methilenedioxyflavone and coumarin were identified. However, only coumarin showed insecticide activity against three insect pests (LD 50 from 2.72 to 39.71 mg g -1 a.i.). The increasing order of insects susceptibility to coumarin was R. dominica, S. zeamais and O. surinamensis. (author)

  6. Antioxidant Activity of Novel Fused Heterocyclic Compounds Derived from Tetrahydropyrimidine Derivative.

    Science.gov (United States)

    Salem, Marwa Sayed; Farhat, Mahmoud; Errayes, Asma Omar; Madkour, Hassan Mohamed Fawzy

    2015-01-01

    6-(Benzo[d][1,3]dioxol-5-yl)-4-oxo-2-thioxo-1,2,3,4-tetrahydropyrimidine-5-carbonitrile has been utilized for synthesis of the fused heterocyclic compounds namely thiazolopyrimidines, tetrazolopyrimidine, pyrimidoquinazoline, pyrimidothiazolopyrimidine, pyrimidothiazolotriazine and pyrrolothiazolopyrimidine derivatives. The newly synthesized compounds were characterized by IR, (1)H-NMR, (13)C-NMR, and mass spectral data. Antioxidant activities of all synthesized compounds were investigated.

  7. Extraction and antioxidant activity of phenolic compounds from ...

    African Journals Online (AJOL)

    35:1, temperature: 70 oC, the experimental total phenolic yield was 30.464 ± 0.025, which agreed with ... The phenolic compounds showed strong antioxidant activities. At extract ..... under steam explosion is a suitable approach for obtaining a ...

  8. Photocatalytic performance of cylindrical reactor inserted with UV light-emitting-diodes for purification of low-level toxic volatile organic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Jo, Wan K., E-mail: wkjo@knu.ac.kr [Department of Environmental Engineering, Kyungpook National University, Daegu, 702-701 (Korea, Republic of); Kang, Hyun J., E-mail: khj435@naver.com [Department of Environmental Engineering, Kyungpook National University, Daegu, 702-701 (Korea, Republic of)

    2012-10-15

    Highlights: Black-Right-Pointing-Pointer Photocatalyst baked at 350 Degree-Sign C exhibited the highest BTEX degradation efficiency. Black-Right-Pointing-Pointer Conventional lamp evidenced a higher degradation efficiency compared to LEDs. Black-Right-Pointing-Pointer LEDs was more energy-efficient than conventional lamp for BTEX degradation. Black-Right-Pointing-Pointer As the residence time increased, the average degradation efficiency increased. - Abstract: The present study investigated the photocatalytic performance of a cylindrical reactor inserted with UV light-emitting-diodes for the decomposition of low-level (0.1 ppm) gas-phase organic compounds (benzene, toluene, ethyl benzene and xylene (BTEX)). The morphological and optical properties of photocatalysts (Degussa P-25 TiO{sub 2}) baked at different temperatures were determined using a range of spectral instruments. The photocatalyst baked at 350 Degree-Sign C exhibited the highest conversion efficiencies for both benzene and toluene (81 and {approx}100%, respectively). The conventional lamp showed a higher conversion efficiency for benzene compared to the 380-nm UV-LED and a higher conversion efficiency for benzene and toluene than the 365-nm UV-LED. However, the ratios of conversion efficiency to electric power consumption were 2.5-3.0 times higher for the latter light source than the former source. Moreover, as the residence time increased from 0.2 to 1.2 min, the average conversion efficiencies for BTEX of the 3-h photocatalytic process increased from nearly zero to 81%, 7 to nearly 100%, 20 to nearly 100%, and 29-30 to nearly 100%, respectively. The cylindrical photocatalytic reactor inserted with UV-LEDs could be energy-efficiently applied for the decomposition of low-level toxic compounds after optimization of the operating conditions.

  9. Photocatalytic performance of cylindrical reactor inserted with UV light-emitting-diodes for purification of low-level toxic volatile organic compounds

    International Nuclear Information System (INIS)

    Jo, Wan K.; Kang, Hyun J.

    2012-01-01

    Highlights: ► Photocatalyst baked at 350 °C exhibited the highest BTEX degradation efficiency. ► Conventional lamp evidenced a higher degradation efficiency compared to LEDs. ► LEDs was more energy-efficient than conventional lamp for BTEX degradation. ► As the residence time increased, the average degradation efficiency increased. - Abstract: The present study investigated the photocatalytic performance of a cylindrical reactor inserted with UV light-emitting-diodes for the decomposition of low-level (0.1 ppm) gas-phase organic compounds (benzene, toluene, ethyl benzene and xylene (BTEX)). The morphological and optical properties of photocatalysts (Degussa P-25 TiO 2 ) baked at different temperatures were determined using a range of spectral instruments. The photocatalyst baked at 350 °C exhibited the highest conversion efficiencies for both benzene and toluene (81 and ∼100%, respectively). The conventional lamp showed a higher conversion efficiency for benzene compared to the 380-nm UV-LED and a higher conversion efficiency for benzene and toluene than the 365-nm UV-LED. However, the ratios of conversion efficiency to electric power consumption were 2.5–3.0 times higher for the latter light source than the former source. Moreover, as the residence time increased from 0.2 to 1.2 min, the average conversion efficiencies for BTEX of the 3-h photocatalytic process increased from nearly zero to 81%, 7 to nearly 100%, 20 to nearly 100%, and 29–30 to nearly 100%, respectively. The cylindrical photocatalytic reactor inserted with UV-LEDs could be energy-efficiently applied for the decomposition of low-level toxic compounds after optimization of the operating conditions.

  10. Organic light emitting diode with light extracting electrode

    Energy Technology Data Exchange (ETDEWEB)

    Bhandari, Abhinav; Buhay, Harry

    2017-04-18

    An organic light emitting diode (10) includes a substrate (20), a first electrode (12), an emissive active stack (14), and a second electrode (18). At least one of the first and second electrodes (12, 18) is a light extracting electrode (26) having a metallic layer (28). The metallic layer (28) includes light scattering features (29) on and/or in the metallic layer (28). The light extracting features (29) increase light extraction from the organic light emitting diode (10).

  11. Characterization of aroma-active compounds in raw and cooked pine-mushrooms (Tricholoma matsutake Sing.).

    Science.gov (United States)

    Cho, In Hee; Kim, Se Young; Choi, Hyung-Kyoon; Kim, Young-Suk

    2006-08-23

    The characteristic aroma-active compounds in raw and cooked pine-mushrooms (Tricholoma matsutake Sing.) were investigated by gas chromatography-olfactometry using aroma extract dilution analysis. 1-Octen-3-one (mushroom-like) was the major aroma-active compound in raw pine-mushrooms; this compound had the highest flavor dilution factor, followed by ethyl 2-methylbutyrate (floral and sweet), linalool (citrus-like), methional (boiled potato-like), 3-octanol (mushroom-like and buttery), 1-octen-3-ol (mushroom-like), (E)-2-octen-1-ol (mushroom-like), and 3-octanone (mushroom-like and buttery). By contrast, methional, 2-acetylthiazole (roasted), an unknown compound (chocolate-like), 3-hydroxy-2-butanone (buttery), and phenylacetaldehyde (floral and sweet), which could be formed by diverse thermal reactions during the cooking process, together with C8 compounds, were identified as the major aroma-active compounds in cooked pine-mushrooms.

  12. Antioxidant and Anti-Osteoporotic Activities of Aromatic Compounds and Sterols from Hericium erinaceum.

    Science.gov (United States)

    Li, Wei; Lee, Sang Hyun; Jang, Hae Dong; Ma, Jin Yeul; Kim, Young Ho

    2017-01-11

    Hericium erinaceum , commonly called lion's mane mushroom, is a traditional edible mushroom widely used in culinary applications and herbal medicines in East Asian countries. In this study, a new sterol, cerevisterol 6-cinnamate ( 6 ), was isolated from the fruiting bodies of H. erinaceum together with five aromatic compounds 1 - 5 and five sterols 7 - 11 . The chemical structures of these compounds were elucidated using chemical and physical methods and comparison of HRESIMS, ¹D-NMR (¹H, 13 C, and DEPT) and 2D-NMR (COSY, HMQC, HMBC, and NOESY) spectra with previously reported data. The antioxidant and anti-osteoporotic activities of extracts and the isolated compounds 1 - 11 were investigated. All compounds exhibited peroxyl radical-scavenging capacity but only compounds 1 , 3 , and 4 showed potent reducing capacity. Moreover, compounds 1 , 2 , 4 , and 5 showed moderate effects on cellular antioxidant activity and inhibited the receptor activator of nuclear factor κB ligand (RANKL)-induced osteoclastic differentiation. These results suggested that H. erinaceum could be utilized in the development of natural antioxidant and anti-osteoporotic nutraceuticals and functional foods.

  13. Biogenic volatile organic compound (BVOC) emissions from forested areas in Turkey: Determination of specific emission rates for thirty-one tree species

    International Nuclear Information System (INIS)

    Aydin, Yagmur Meltem; Yaman, Baris; Koca, Husnu; Dasdemir, Okan; Kara, Melik; Altiok, Hasan; Dumanoglu, Yetkin; Bayram, Abdurrahman; Tolunay, Doganay; Odabasi, Mustafa; Elbir, Tolga

    2014-01-01

    Normalized biogenic volatile organic compound (BVOC) emission rates for thirty one tree species that cover the 98% of national forested areas in Turkey were determined. Field samplings were performed at fourteen different forested areas in Turkey using a specific dynamic enclosure system. The selected branches of tree species were enclosed in a chamber consisted of a transparent Nalofan bag. The air-flows were sampled from both inlet and outlet of the chamber by Tenax-filled sorbent tubes during photosynthesis of trees under the presence of sunlight. Several environmental parameters (temperature, humidity, photosynthetically active radiation-PAR, and CO 2 ) were continuously monitored inside and outside the enclosure chamber during the samplings. Collected samples were analyzed using a gas chromatography mass spectrometry (GC/MS) system equipped with a thermal desorber (TD). Sixty five BVOCs classified in five major groups (isoprene, monoterpenes, sesquiterpenes, oxygenated sesquiterpenes, and other oxygenated compounds) were analyzed. Emission rates were determined by normalization to standard conditions (1000 μmol/m 2 s PAR and 30 °C temperature for isoprene and 30 °C temperature for the remaining compounds). In agreement with the literature, isoprene was mostly emitted by broad-leaved trees while coniferous species mainly emitted monoterpenes. Several tree species such as Sweet Chestnut, Silver Lime, and European Alder had higher monoterpene emissions although they are broad-leaved species. High isoprene emissions were also observed for a few coniferous species such as Nordmann Fir and Oriental Spruce. The highest normalized total BVOC emission rate of 27.1 μg/g h was observed for Oriental Plane while South European Flowering Ash was the weakest BVOC emitter with a total normalized emission rate of 0.031 μg/g h. Monoterpene emissions of broad-leaved species mainly consisted of sabinene, limonene and trans-beta-ocimene, while alpha-pinene, beta-pinene and

  14. Biogenic volatile organic compound (BVOC) emissions from forested areas in Turkey: Determination of specific emission rates for thirty-one tree species

    Energy Technology Data Exchange (ETDEWEB)

    Aydin, Yagmur Meltem; Yaman, Baris; Koca, Husnu; Dasdemir, Okan; Kara, Melik; Altiok, Hasan; Dumanoglu, Yetkin; Bayram, Abdurrahman [Department of Environmental Engineering, Faculty of Engineering, Dokuz Eylul University, Tinaztepe Campus, Buca, Izmir (Turkey); Tolunay, Doganay [Department of Soil Science and Ecology, Faculty of Forestry, Istanbul University, Bahcekoy, Istanbul (Turkey); Odabasi, Mustafa [Department of Environmental Engineering, Faculty of Engineering, Dokuz Eylul University, Tinaztepe Campus, Buca, Izmir (Turkey); Elbir, Tolga, E-mail: tolga.elbir@deu.edu.tr [Department of Environmental Engineering, Faculty of Engineering, Dokuz Eylul University, Tinaztepe Campus, Buca, Izmir (Turkey)

    2014-08-15

    Normalized biogenic volatile organic compound (BVOC) emission rates for thirty one tree species that cover the 98% of national forested areas in Turkey were determined. Field samplings were performed at fourteen different forested areas in Turkey using a specific dynamic enclosure system. The selected branches of tree species were enclosed in a chamber consisted of a transparent Nalofan bag. The air-flows were sampled from both inlet and outlet of the chamber by Tenax-filled sorbent tubes during photosynthesis of trees under the presence of sunlight. Several environmental parameters (temperature, humidity, photosynthetically active radiation-PAR, and CO{sub 2}) were continuously monitored inside and outside the enclosure chamber during the samplings. Collected samples were analyzed using a gas chromatography mass spectrometry (GC/MS) system equipped with a thermal desorber (TD). Sixty five BVOCs classified in five major groups (isoprene, monoterpenes, sesquiterpenes, oxygenated sesquiterpenes, and other oxygenated compounds) were analyzed. Emission rates were determined by normalization to standard conditions (1000 μmol/m{sup 2} s PAR and 30 °C temperature for isoprene and 30 °C temperature for the remaining compounds). In agreement with the literature, isoprene was mostly emitted by broad-leaved trees while coniferous species mainly emitted monoterpenes. Several tree species such as Sweet Chestnut, Silver Lime, and European Alder had higher monoterpene emissions although they are broad-leaved species. High isoprene emissions were also observed for a few coniferous species such as Nordmann Fir and Oriental Spruce. The highest normalized total BVOC emission rate of 27.1 μg/g h was observed for Oriental Plane while South European Flowering Ash was the weakest BVOC emitter with a total normalized emission rate of 0.031 μg/g h. Monoterpene emissions of broad-leaved species mainly consisted of sabinene, limonene and trans-beta-ocimene, while alpha-pinene, beta

  15. Supercritical Algal Extracts: A Source of Biologically Active Compounds from Nature

    Directory of Open Access Journals (Sweden)

    Izabela Michalak

    2015-01-01

    Full Text Available The paper discusses the potential applicability of the process of supercritical fluid extraction (SFE in the production of algal extracts with the consideration of the process conditions and yields. State of the art in the research on solvent-free isolation of biologically active compounds from the biomass of algae was presented. Various aspects related with the properties of useful compounds found in cells of microalgae and macroalgae were discussed, including their potential applications as the natural components of plant protection products (biostimulants and bioregulators, dietary feed and food supplements, and pharmaceuticals. Analytical methods of determination of the natural compounds derived from algae were discussed. Algal extracts produced by SFE process enable obtaining a solvent-free concentrate of biologically active compounds; however, detailed economic analysis, as well as elaboration of products standardization procedures, is required in order to implement the products in the market.

  16. Anti-Inflammatory Activity of Compounds Isolated from Plants

    Directory of Open Access Journals (Sweden)

    R.M. Perez G.

    2001-01-01

    Full Text Available This review shows over 300 compounds isolated and identified from plants that previously demonstrated anti-inflammatory activity. They have been classified in appropriate chemical groups and data are reported on their pharmacological effects, mechanisms of action, and other properties.

  17. Adsorption of aromatic compounds from the biodegradation of azo dyes on activated carbon

    Science.gov (United States)

    Faria, P. C. C.; Órfão, J. J. M.; Figueiredo, J. L.; Pereira, M. F. R.

    2008-03-01

    The adsorption of three selected aromatic compounds (aniline, sulfanilic acid and benzenesulfonic acid) on activated carbons with different surface chemical properties was investigated at different solution pH. A fairly basic commercial activated carbon was modified by means of chemical treatment with HNO 3, yielding an acid activated carbon. The textural properties of this sample were not significantly changed after the oxidation treatment. Equilibrium isotherms of the selected compounds on the mentioned samples were obtained and the results were discussed in relation to their surface chemistry. The influence of electrostatic and dispersive interactions involved in the uptake of the compounds studied was evaluated. The Freundlich model was used to fit the experimental data. Higher uptakes are attained when the compounds are present in their molecular form. In general, adsorption was disfavoured by the introduction of oxygen-containing groups on the surface of the activated carbon.

  18. Role of Biogenic Volatile Organic Compounds (BVOC) emitted by urban trees on ozone concentration in cities: A review

    International Nuclear Information System (INIS)

    Calfapietra, C.; Fares, S.; Manes, F.; Morani, A.; Sgrigna, G.; Loreto, F.

    2013-01-01

    Biogenic Volatile Organic Compounds (BVOC) play a critical role in biosphere–atmosphere interactions and are key factors of the physical and chemical properties of the atmosphere and climate. However, few studies have been carried out at urban level to investigate the interactions between BVOC emissions and ozone (O 3 ) concentration. The contribution of urban vegetation to the load of BVOCs in the air and the interactions between biogenic emissions and urban pollution, including the likely formation of O 3 , needs to be investigated, but also the effects of O 3 on the biochemical reactions and physiological conditions leading to BVOC emissions are largely unknown. The effect of BVOC emission on the O 3 uptake by the trees is further complicating the interactions BVOC–O 3 , thus making challenging the estimation of the calculation of BVOC effect on O 3 concentration at urban level. -- Highlights: • We examine the role of BVOC emitted from urban trees for O 3 formation in our cities. • We state that the high BVOC emitter trees are dangerous especially in VOC limited conditions for ozone formation. • We conclude that the choice of the tree species can be very important for the quality of the air in our cities. -- BVOC emission from urban trees can be very important for ozone concentration

  19. In vitro antimicrobial activity of extracts and isolated compound from Dalbergia stipulacea Roxb. leaves

    Science.gov (United States)

    Kumar, Arvind; Bhat, Tahir Ahmad; Singh, Rattan Deep

    2017-07-01

    The study was designed to examine the in vitro antimicrobial efficacy of extracts and isolated compound of Dalbergia stipulacea. Combined extracts (chloroform and methanol) of plant leaves fractionated with n-butanol loaded with column afforded a flavonoid glycoside compound identified as luteolin 4'-rutinoside. Different extracts and isolated compound exhibited pronounced antibacterial and antifungal varied activities against four bacteria (Clostridium acetobutylinium, Bacillus subtilis, Streptococcus mutans, and Pseudomonas sp.) and one fungus (Candida albicans) susceptibility were determined using disc diffusion method. The minimum inhibitory concentration (MIC) of extracts and isolated compounds was determined by broth dilution method. The maximum activity was shown by chloroform extract against C. albicans with a zone of inhibition of 17 mm and minimum activity was displayed by methanolic extract against Pseudomonas sp. with 5 mm. However, isolated compound has shown maximum activity against Pseudomonas sp. with 15 mm. The MIC values higher in methanol extract against Pseudomonas sp. and isolated compound shows good against Pseudomonas sp. and B. subtilis. Our findings indicate that plant could be used as a good antimicrobial agent in food, pharmaceutical and bio-pesticide industries.

  20. Antibacterial assay-guided isolation of active compounds from Artocarpus heterophyllus heartwoods.

    Science.gov (United States)

    Septama, Abdi Wira; Panichayupakaranant, Pharkphoom

    2015-01-01

    Preparations from Artocarpus heterophyllus Lam. (Moraceae) heartwoods are used in the traditional folk medicine for the treatment of inflammation, malarial fever, and to prevent bacterial and fungal infections. The objective of this study was to isolate pure antibacterial compounds from A. heterophyllus heartwoods. The dried and powdered A. heterophyllus heartwoods were successively extracted with the following solvents: hexane, ethyl acetate, and methanol. Each of the extracts was screened for their antibacterial activities using a disc diffusion method (10 mg/disc). Their minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) were determined using a broth microdilution method. The extract that showed the strongest antibacterial activities was fractionated to isolate the active compounds by an antibacterial assay-guided isolation process. The ethyl acetate extract exhibited the strongest antibacterial activities against Streptococcus mutans, S. pyogenes, and Bacillus subtilis with MIC values of 78, 39, and 9.8 µg/mL, respectively. Based on an antibacterial assay-guided isolation, four antibacterial compounds: cycloartocarpin (1), artocarpin (2), artocarpanone (3), and cyanomaclurin (4) were purified. Among these isolated compounds, artocarpin exhibited the strongest antibacterial activity against Gram-positive bacteria, including S. mutans, S. pyogenes, B. subtilis, Staphylococcus aureus, and S. epidermidis with MICs of 4.4, 4.4, 17.8, 8.9, and 8.9 µM, respectively, and MBCs of 8.9, 8.9, 17.8, 8.9, and 8.9 µM, respectively, while artocarpanone showed the strongest activity against Escherichia coli, a Gram-negative bacteria with MIC and MBC values of 12.9 and 25.8 µM, respectively. Only artocarpin showed inhibitory activity against Pseudomonas aeruginosa with an MIC of 286.4 µM.

  1. Plant compounds insecticide activity against Coleoptera pests of stored products

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, Marcio Dionizio; Picanco, Marcelo Coutinho; Guedes, Raul Narciso Carvalho; Campos, Mateus Ribeiro de; Silva, Gerson Adriano; Martins, Julio Claudio [Universidade Federal de Vicosa (UFV), MG (Brazil). Dept. de Biologia Animal]. E-mail: marcio.dionizio@gmail.com; picanco@ufv.br; guedes@ufv.br; mateusc3@yahoo.com.br; agronomiasilva@yahoo.com.br

    2007-07-15

    The objective of this work was to screen plants with insecticide activity, in order to isolate, identify and assess the bioactivity of insecticide compounds present in these plants, against Coleoptera pests of stored products: Oryzaephilus surinamensis L. (Silvanidae), Rhyzopertha dominica F. (Bostrichidae) and Sitophilus zeamais Mots. (Curculionidae). The plant species used were: basil (Ocimum selloi Benth.), rue (Ruta graveolens L.), lion's ear (Leonotis nepetifolia (L.) R.Br.), jimson weed (Datura stramonium L.), baleeira herb (Cordia verbenacea L.), mint (Mentha piperita L.), wild balsam apple (Mormodica charantia L.), and billy goat weed or mentrasto (Ageratum conyzoides L.). The insecticide activity of hexane and ethanol extracts from those plants on R. dominica was evaluated. Among them, only hexane extract of A. conyzoides showed insecticide activity; the hexane extract of this species was successively fractionated by silica gel column chromatography, for isolation and purification of the active compounds. Compounds 5,6,7,8,3',4',5'-heptamethoxyflavone; 5,6,7,8,3'-pentamethoxy-4',5'-methilenedioxyflavone and coumarin were identified. However, only coumarin showed insecticide activity against three insect pests (LD{sub 50} from 2.72 to 39.71 mg g{sup -1} a.i.). The increasing order of insects susceptibility to coumarin was R. dominica, S. zeamais and O. surinamensis. (author)

  2. Volatile and semivolatile organic compounds in laboratory peat fire emissions

    Data.gov (United States)

    U.S. Environmental Protection Agency — Supporting information Tables S3 and S4 list emission factors in g/kg of speciated volatile and particulate organic compounds emitted from peat burning. Peat samples...

  3. Near UV-Blue Excitable Green-Emitting Nanocrystalline Oxide

    Directory of Open Access Journals (Sweden)

    C. E. Rodríguez-García

    2011-01-01

    Full Text Available Green-emitting Eu-activated powders were produced by a two-stage method consisting of pressure-assisted combustion synthesis and postannealing in ammonia. The as-synthesized powders exhibited a red photoluminescence (PL peak located at =616 nm when excited with =395 nm UV. This emission peak corresponds to the 5D0→7F2 transition in Eu3+. After annealing in ammonia, the PL emission changed to an intense broad-band peak centered at =500 nm, most likely produced by 4f65d1→4f7 electronic transitions in Eu2+. This green-emitting phosphor has excitation band in the near UV-blue region (=300–450 nm. X-ray diffraction analysis reveals mainly the orthorhombic EuAlO3 and Al2O3 phases. Transmission electron microscopy observations showed that the grains are formed by faceted nanocrystals (~4 nm of polygonal shape. The excellent excitation and emission properties make these powders very promising to be used as phosphors in UV solid-state diodes coupled to activate white-emitting lamps.

  4. Porritoxins, metabolites of Alternaria porri, as anti-tumor-promoting active compounds.

    Science.gov (United States)

    Horiuchi, Masayuki; Tokuda, Harukuni; Ohnishi, Keiichiro; Yamashita, Masakazu; Nishino, Hoyoku; Maoka, Takashi

    2006-02-01

    To search for possible cancer chemopreventive agents from natural sources, we performed primary screening of metabolites of Alternaria porri by examining their possible inhibitory effects on Epstein-Barr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorbol-13-acetate (TPA) in Raji cells. The ethyl acetate extract of A. porri showed the inhibitory effect on EBV-EA activation. Three porritoxins (1-3) were obtained as inhibitory active compounds for EBV-EA from ethyl acetate extract. 6-(3',3'-Dimethylallyloxy)-4-methoxy-5-methylphthalide (2) showed the strongest activity among them. Inhibitory effect of porritoxin (1) and (2) was superior to that of beta-carotene, a well-known anti-tumor promoter. Furthermore, the structure-activity correlation of porritoxins and their related compounds were discussed.

  5. Effect of vanadium compounds on acid phosphatase activity.

    Science.gov (United States)

    Vescina, C M; Sálice, V C; Cortizo, A M; Etcheverry, S B

    1996-01-01

    The direct effect of different vanadium compounds on acid phosphatase (ACP) activity was investigated. Vanadate and vanadyl but not pervanadate inhibited the wheat germ ACP activity. These vanadium derivatives did not alter the fibroblast Swiss 3T3 soluble fraction ACP activity. Using inhibitors of tyrosine phosphatases (PTPases), the wheat germ ACP was partially characterized as a PTPase. This study suggests that the inhibitory ability of different vanadium derivatives to modulate ACP activity seems to depend on the geometry around the vanadium atom more than on the oxidation state. Our results indicate a correlation between the PTPase activity and the sensitivity to vanadate and vanadyl cation.

  6. Natural products as a resource for biologically active compounds

    International Nuclear Information System (INIS)

    Hanke, F.J.

    1986-01-01

    The goal of this study was to investigate various sources of biologically active natural products in an effort to identify the active pesticidal compounds involved. The study is divided into several parts. Chapter 1 contains a discussion of several new compounds from plant and animal sources. Chapter 2 introduces a new NMR technique. In section 2.1 a new technique for better utilizing the lanthanide relaxation agent Gd(fod) 3 is presented which allows the predictable removal of resonances without line broadening. Section 2.2 discusses a variation of this technique for use in an aqueous solvent by applying this technique towards identifying the binding sites of metals of biological interest. Section 2.3 presents an unambiguous 13 C NMR assignment of melibiose. Chapter 3 deals with work relating to the molting hormone of most arthropods, 20-hydroxyecdysone. Section 3.1 discusses the use of two-dimensional NMR (2D NMR) to assign the 1 H NMR spectrum of this biologically important compound. Section 3.2 presents a new application for Droplet countercurrent chromatography (DCCC). Chapter 4 presents a basic improvement to the commercial DCCC instrument that is currently being applied to future commercial instruments. Chapter 5 discusses a curious observation of the effects that two previously known compounds, nagilactone C and (-)-epicatechin, have on lettuce and rice and suggest a possible new role for the ubiquitous flavanol (-)-epicatechin in plants

  7. Blue-Emitting Arylalkynyl Naphthalene Derivatives via a Hexadehydro-Diels-Alder Cascade Reaction.

    Science.gov (United States)

    Xu, Feng; Hershey, Kyle W; Holmes, Russell J; Hoye, Thomas R

    2016-10-05

    We describe here three alkynyl substituted naphthalenes that display promising luminescence characteristics. Each compound is easily and efficiently synthesized in three steps by capitalizing on the hexadehydro-Diels-Alder (HDDA) cycloisomerization reaction in which an intermediate benzyne is captured by tetraphenylcyclopentadienone, a classical trap for benzyne itself. These compounds luminesce in the deep blue when stimulated either optically (i.e., photoluminescence in both solution and solid films) or electrically [in a light-emitting diode (LED)]. The photophysical properties are relatively insensitive to the electronic nature of the substituents (H, OMe, CO 2 Me) that define these otherwise identical compounds. Overall, our observations suggest that the twisted nature of the five adjacent aryl groups serves to minimize the intermolecular interaction between core naphthalene units in different sample morphologies. These compounds represent promising leads for the identification of others of value as the emissive component of organic LEDs (OLEDs).

  8. The Switch from Low-Pressure Sodium to Light Emitting Diodes Does Not Affect Bat Activity at Street Lights.

    Directory of Open Access Journals (Sweden)

    Elizabeth G Rowse

    Full Text Available We used a before-after-control-impact paired design to examine the effects of a switch from low-pressure sodium (LPS to light emitting diode (LED street lights on bat activity at twelve sites across southern England. LED lights produce broad spectrum 'white' light compared to LPS street lights that emit narrow spectrum, orange light. These spectral differences could influence the abundance of insects at street lights and thereby the activity of the bats that prey on them. Most of the bats flying around the LPS lights were aerial-hawking species, and the species composition of bats remained the same after the switch-over to LED. We found that the switch-over from LPS to LED street lights did not affect the activity (number of bat passes, or the proportion of passes containing feeding buzzes, of those bat species typically found in close proximity to street lights in suburban environments in Britain. This is encouraging from a conservation perspective as many existing street lights are being, or have been, switched to LED before the ecological consequences have been assessed. However, lighting of all spectra studied to date generally has a negative impact on several slow-flying bat species, and LED lights are rarely frequented by these 'light-intolerant' bat species.

  9. The Switch from Low-Pressure Sodium to Light Emitting Diodes Does Not Affect Bat Activity at Street Lights

    Science.gov (United States)

    Rowse, Elizabeth G.; Harris, Stephen; Jones, Gareth

    2016-01-01

    We used a before-after-control-impact paired design to examine the effects of a switch from low-pressure sodium (LPS) to light emitting diode (LED) street lights on bat activity at twelve sites across southern England. LED lights produce broad spectrum ‘white’ light compared to LPS street lights that emit narrow spectrum, orange light. These spectral differences could influence the abundance of insects at street lights and thereby the activity of the bats that prey on them. Most of the bats flying around the LPS lights were aerial-hawking species, and the species composition of bats remained the same after the switch-over to LED. We found that the switch-over from LPS to LED street lights did not affect the activity (number of bat passes), or the proportion of passes containing feeding buzzes, of those bat species typically found in close proximity to street lights in suburban environments in Britain. This is encouraging from a conservation perspective as many existing street lights are being, or have been, switched to LED before the ecological consequences have been assessed. However, lighting of all spectra studied to date generally has a negative impact on several slow-flying bat species, and LED lights are rarely frequented by these ‘light-intolerant’ bat species. PMID:27008274

  10. Organic compound emissions from a landfarm used for oil and gas solid waste disposal.

    Science.gov (United States)

    Lyman, Seth N; Mansfield, Marc L

    2018-04-13

    Solid or sludgy hydrocarbon waste is a by-product of oil and gas exploration and production. One commonly used method of disposing of this waste is landfarming. Landfarming involves spreading hydrocarbon waste on soils, tilling it into the soil, and allowing it to biodegrade. We used a dynamic flux chamber to measure fluxes of methane, a suite of 54 nonmethane hydrocarbons, and light alcohols from an active and a remediated landfarm in eastern Utah. Fluxes from the remediated landfarm were not different from a polytetrafluoroethylene (PTFE) sheet or from undisturbed soils in the region. Fluxes of methane, total nonmethane hydrocarbons, and alcohols from the landfarm in active use were 1.41 (0.37, 4.19) (mean and 95% confidence limits), 197.90 (114.72, 370.46), and 4.17 (0.03, 15.89) mg m -2  hr -1 , respectively. Hydrocarbon fluxes were dominated by alkanes, especially those with six or more carbons. A 2-ha landfarm with fluxes of the magnitude we observed in this study would emit 95.3 (54.3, 179.7) kg day -1 of total hydrocarbons, including 11.2 (4.3, 33.9) kg day -1 of BTEX (benzene, toluene, ethylbenzene, and xylenes). Solid and sludgy hydrocarbon waste from the oil and gas industry is often disposed of by landfarming, in which wastes are tilled into soil and allowed to decompose. We show that a land farm in Utah emitted a variety of organic compounds into the atmosphere, including hazardous air pollutants and compounds that form ozone. We calculate that a 2-ha landfarm facility would emit 95.0 ± 66.0 kg day -1 of total hydrocarbons, including 11.1 ± 1.5 kg day -1 of BTEX (benzene, toluene, ethylbenzene, and xylenes).

  11. Power output and efficiency of beta-emitting microspheres

    International Nuclear Information System (INIS)

    Cheneler, David; Ward, Michael

    2015-01-01

    Current standard methods to calculate the dose of radiation emitted during medical applications by beta-minus emitting microspheres rely on an over-simplistic formalism. This formalism is a function of the average activity of the radioisotope used and the physiological dimensions of the patient only. It neglects the variation in energy of the emitted beta particle due to self-attenuation, or self-absorption, effects related to the finite size of the sphere. Here it is assumed the sphere is comprised of a pure radioisotope with beta particles being emitted isotropically throughout the material. The full initial possible kinetic energy distribution of a beta particle is taken into account as well as the energy losses due to scattering by other atoms in the microsphere and bremsstrahlung radiation. By combining Longmire’s theory of the mean forward range of charged particles and the Rayleigh distribution to take into account the statistical nature of scattering and energy straggling, the linear attenuation, or self-absorption, coefficient for beta-emitting radioisotopes has been deduced. By analogy with gamma radiation transport in spheres, this result was used to calculate the rate of energy emitted by a beta-emitting microsphere and its efficiency. Comparisons to standard point dose kernel formulations generated using Monte Carlo data show the efficacy of the proposed method. Yttrium-90 is used as a specific example throughout, as a medically significant radioisotope, frequently used in radiation therapy for treating cancer. - Highlights: • Range-energy relationship for the beta particles in yttrium-90 is calculated. • Formalism for the semi-analytical calculation of self-absorption coefficients. • Energy-dependent self-absorption coefficient calculated for yttrium-90. • Flux rate of beta particles from a self-attenuating radioactive sphere is shown. • The efficiency of beta particle emitting radioactive microspheres is calculated

  12. Quantitation in PET using isotopes emitting prompt single gammas: application to yttrium-86

    International Nuclear Information System (INIS)

    Walrand, Stephan; Jamar, Francois; Mathieu, Isabelle; De Camps, Joelle; Lonneux, Max; Pauwels, Stanislas; Sibomana, Merence; Labar, Daniel; Michel, Christian

    2003-01-01

    Several yttrium-90 labelled somatostatin analogues are now available for cancer radiotherapy. After injection, a large amount of the compound is excreted via the urinary tract, while a variable part is trapped in the tumour(s), allowing the curative effect. Unfortunately, the compound may also be trapped in critical tissues such as kidney or bone marrow. As a consequence, a method for assessment of individual biodistribution and pharmacokinetics is required to predict the maximum dose that can be safely injected into patients. However, 90 Y, a pure β - particle emitter, cannot be used for quantitative imaging. Yttrium-86 is a positron emitter that allows imaging of tissue uptake using a PET camera. In addition to the positron, 86 Y also emits a multitude of prompt single γ-rays, leading to significant overestimation of uptake when using classical reconstruction methods. We propose a patient-dependent correction method based on sinogram tail fitting using an 86 Y point spread function library. When applied to abdominal phantom acquisition data, the proposed correction method significantly improved the accuracy of the quantification: the initial overestimation of background activity by 117% was reduced to 9%, while the initial error in respect of kidney uptake by 84% was reduced to 5%. In patient studies, the mean discrepancy between PET total body activity and the activity expected from urinary collections was reduced from 92% to 7%, showing the benefit of the proposed correction method. (orig.)

  13. A ranking method for the concurrent learning of compounds with various activity profiles.

    Science.gov (United States)

    Dörr, Alexander; Rosenbaum, Lars; Zell, Andreas

    2015-01-01

    In this study, we present a SVM-based ranking algorithm for the concurrent learning of compounds with different activity profiles and their varying prioritization. To this end, a specific labeling of each compound was elaborated in order to infer virtual screening models against multiple targets. We compared the method with several state-of-the-art SVM classification techniques that are capable of inferring multi-target screening models on three chemical data sets (cytochrome P450s, dehydrogenases, and a trypsin-like protease data set) containing three different biological targets each. The experiments show that ranking-based algorithms show an increased performance for single- and multi-target virtual screening. Moreover, compounds that do not completely fulfill the desired activity profile are still ranked higher than decoys or compounds with an entirely undesired profile, compared to other multi-target SVM methods. SVM-based ranking methods constitute a valuable approach for virtual screening in multi-target drug design. The utilization of such methods is most helpful when dealing with compounds with various activity profiles and the finding of many ligands with an already perfectly matching activity profile is not to be expected.

  14. Coordination compounds of rare-earth metals with organic ligands for electroluminescent diodes

    International Nuclear Information System (INIS)

    Katkova, M A; Bochkarev, Mikhail N; Vitukhnovsky, Alexey G

    2005-01-01

    Data on lanthanide coordination compounds with organic ligands used in the design of electroluminescent diodes are summarised and systematically represented. The molecular and electronic structures and spectroscopic characteristics of these compounds are considered. A comparative analysis of the properties of organic electroluminescent diodes with different compositions of emitting and conductive layers is presented.

  15. Calorimetric measurement of strong γ emitting sources

    International Nuclear Information System (INIS)

    Brangier, B.; Herczeg, C.; Henry, R.

    1968-01-01

    This publication gives the principle and a description of an adiabatic calorimeter for measuring the real activity of strong gamma-emitting sources by absorbing the emitted energy in a mass of copper. Because of the difficulty of evaluating the amount self- absorption, we have built a calorimeter for measuring the self- absorption, and a description of it is given.The results of these three measurements are fairly satisfactory. The calibration and the actual measurements obtained are given with a few corrections made necessary by the design of the apparatus. The correlation of the various results is discussed. (author) [fr

  16. Real-time monitoring and analysis of nutrient transportation in a living plant using a positron emitting tracer imaging system (PETIS)

    International Nuclear Information System (INIS)

    Matsuhashi, Shinpei

    2005-01-01

    We visualized the uptake and transportation of nutrition in a living plant using positron-emitting tracers and mathematical analysis of the data. We have been developing a positron-imaging technique to visualize the uptake and transportation of nutrients in a plant by a positron-emitting tracer-imaging system (PETIS) using positron-emitting nuclide-labeled compounds. The PETIS data is analyzed mathematically to understand the physiological meaning of the physical parameters. In this study, the results on the uptake and transportation of nutrients, which were obtained with the use of a positron-imaging method, are introduced. (author)

  17. Investigation of Volatiles Emitted from Freshly Cut Onions (Allium cepa L. by Real Time Proton-Transfer Reaction-Mass Spectrometry (PTR-MS

    Directory of Open Access Journals (Sweden)

    Mette Marie Løkke

    2012-11-01

    Full Text Available Volatile organic compounds (VOCs in cut onions (Allium cepa L. were continuously measured by PTR-MS during the first 120 min after cutting. The headspace composition changed rapidly due to the very reactive volatile sulfurous compounds emitted from onion tissue after cell disruption. Mass spectral signals corresponding to propanethial S-oxide (the lachrymatory factor and breakdown products of this compound dominated 0–10 min after cutting. Subsequently, propanethiol and dipropyl disulfide predominantly appeared, together with traces of thiosulfinates. The concentrations of these compounds reached a maximum at 60 min after cutting. Propanethiol was present in highest concentrations and had an odor activity value 20 times higher than dipropyl disulfide. Thus, propanethiol is suggested to be the main source of the characteristic onion odor. Monitoring the rapid changes of VOCs in the headspace of cut onion necessitates a high time resolution, and PTR-MS is demonstrated to be a very suitable method for monitoring the headspace of freshly cut onions directly after cutting without extraction or pre-concentration.

  18. Antioxidant and Anti-Osteoporotic Activities of Aromatic Compounds and Sterols from Hericium erinaceum

    Directory of Open Access Journals (Sweden)

    Wei Li

    2017-01-01

    Full Text Available Hericium erinaceum, commonly called lion’s mane mushroom, is a traditional edible mushroom widely used in culinary applications and herbal medicines in East Asian countries. In this study, a new sterol, cerevisterol 6-cinnamate (6, was isolated from the fruiting bodies of H. erinaceum together with five aromatic compounds 1–5 and five sterols 7–11. The chemical structures of these compounds were elucidated using chemical and physical methods and comparison of HRESIMS, 1D-NMR (1H, 13C, and DEPT and 2D-NMR (COSY, HMQC, HMBC, and NOESY spectra with previously reported data. The antioxidant and anti-osteoporotic activities of extracts and the isolated compounds 1–11 were investigated. All compounds exhibited peroxyl radical-scavenging capacity but only compounds 1, 3, and 4 showed potent reducing capacity. Moreover, compounds 1, 2, 4, and 5 showed moderate effects on cellular antioxidant activity and inhibited the receptor activator of nuclear factor κB ligand (RANKL-induced osteoclastic differentiation. These results suggested that H. erinaceum could be utilized in the development of natural antioxidant and anti-osteoporotic nutraceuticals and functional foods.

  19. Anti-trypanosomal activities and structural chemical properties of selected compound classes.

    Science.gov (United States)

    Ponte-Sucre, Alicia; Bruhn, Heike; Schirmeister, Tanja; Cecil, Alexander; Albert, Christian R; Buechold, Christian; Tischer, Maximilian; Schlesinger, Susanne; Goebel, Tim; Fuß, Antje; Mathein, Daniela; Merget, Benjamin; Sotriffer, Christoph A; Stich, August; Krohne, Georg; Engstler, Markus; Bringmann, Gerhard; Holzgrabe, Ulrike

    2015-02-01

    Potent compounds do not necessarily make the best drugs in the market. Consequently, with the aim to describe tools that may be fundamental for refining the screening of candidates for animal and preclinical studies and further development, molecules of different structural classes synthesized within the frame of a broad screening platform were evaluated for their trypanocidal activities, cytotoxicities against murine macrophages J774.1 and selectivity indices, as well as for their ligand efficiencies and structural chemical properties. To advance into their modes of action, we also describe the morphological and ultrastructural changes exerted by selected members of each compound class on the parasite Trypanosoma brucei. Our data suggest that the potential organelles targeted are either the flagellar pocket (compound 77, N-Arylpyridinium salt; 15, amino acid derivative with piperazine moieties), the endoplasmic reticulum membrane systems (37, bisquaternary bisnaphthalimide; 77, N-Arylpyridinium salt; 68, piperidine derivative), or mitochondria and kinetoplasts (88, N-Arylpyridinium salt; 68, piperidine derivative). Amino acid derivatives with fumaric acid and piperazine moieties (4, 15) weakly inhibiting cysteine proteases seem to preferentially target acidic compartments. Our results suggest that ligand efficiency indices may be helpful to learn about the relationship between potency and chemical characteristics of the compounds. Interestingly, the correlations found between the physico-chemical parameters of the selected compounds and those of commercial molecules that target specific organelles indicate that our rationale might be helpful to drive compound design toward high activities and acceptable pharmacokinetic properties for all compound families.

  20. Quinolone Amides as Antitrypanosomal Lead Compounds with In Vivo Activity.

    Science.gov (United States)

    Hiltensperger, Georg; Hecht, Nina; Kaiser, Marcel; Rybak, Jens-Christoph; Hoerst, Alexander; Dannenbauer, Nicole; Müller-Buschbaum, Klaus; Bruhn, Heike; Esch, Harald; Lehmann, Leane; Meinel, Lorenz; Holzgrabe, Ulrike

    2016-08-01

    Human African trypanosomiasis (HAT) is a major tropical disease for which few drugs for treatment are available, driving the need for novel active compounds. Recently, morpholino-substituted benzyl amides of the fluoroquinolone-type antibiotics were identified to be compounds highly active against Trypanosoma brucei brucei Since the lead compound GHQ168 was challenged by poor water solubility in previous trials, the aim of this study was to introduce structural variations to GHQ168 as well as to formulate GHQ168 with the ultimate goal to increase its aqueous solubility while maintaining its in vitro antitrypanosomal activity. The pharmacokinetic parameters of spray-dried GHQ168 and the newly synthesized compounds GHQ242 and GHQ243 in mice were characterized by elimination half-lives ranging from 1.5 to 3.5 h after intraperitoneal administration (4 mice/compound), moderate to strong human serum albumin binding for GHQ168 (80%) and GHQ243 (45%), and very high human serum albumin binding (>99%) for GHQ242. For the lead compound, GHQ168, the apparent clearance was 112 ml/h and the apparent volume of distribution was 14 liters/kg of body weight (BW). Mice infected with T. b. rhodesiense (STIB900) were treated in a stringent study scheme (2 daily applications between days 3 and 6 postinfection). Exposure to spray-dried GHQ168 in contrast to the control treatment resulted in mean survival durations of 17 versus 9 days, respectively, a difference that was statistically significant. Results that were statistically insignificantly different were obtained between the control and the GHQ242 and GHQ243 treatments. Therefore, GHQ168 was further profiled in an early-treatment scheme (2 daily applications at days 1 to 4 postinfection), and the results were compared with those obtained with a control treatment. The result was statistically significant mean survival times exceeding 32 days (end of the observation period) versus 7 days for the GHQ168 and control treatments

  1. High-efficiency electroluminescence and amplified spontaneous emission from a thermally activated delayed fluorescent near-infrared emitter

    Science.gov (United States)

    Kim, Dae-Hyeon; D'Aléo, Anthony; Chen, Xian-Kai; Sandanayaka, Atula D. S.; Yao, Dandan; Zhao, Li; Komino, Takeshi; Zaborova, Elena; Canard, Gabriel; Tsuchiya, Youichi; Choi, Eunyoung; Wu, Jeong Weon; Fages, Frédéric; Brédas, Jean-Luc; Ribierre, Jean-Charles; Adachi, Chihaya

    2018-02-01

    Near-infrared organic light-emitting diodes and semiconductor lasers could benefit a variety of applications including night-vision displays, sensors and information-secured displays. Organic dyes can generate electroluminescence efficiently at visible wavelengths, but organic light-emitting diodes are still underperforming in the near-infrared region. Here, we report thermally activated delayed fluorescent organic light-emitting diodes that operate at near-infrared wavelengths with a maximum external quantum efficiency of nearly 10% using a boron difluoride curcuminoid derivative. As well as an effective upconversion from triplet to singlet excited states due to the non-adiabatic coupling effect, this donor-acceptor-donor compound also exhibits efficient amplified spontaneous emission. By controlling the polarity of the active medium, the maximum emission wavelength of the electroluminescence spectrum can be tuned from 700 to 780 nm. This study represents an important advance in near-infrared organic light-emitting diodes and the design of alternative molecular architectures for photonic applications based on thermally activated delayed fluorescence.

  2. Anti-inflammatory activities of compounds from twigs of Morus alba.

    Science.gov (United States)

    Tran, Huynh Nguyen Khanh; Nguyen, Van Thu; Kim, Jeong Ah; Rho, Seong Soo; Woo, Mi Hee; Choi, Jae Sui; Lee, Jeong-Hyung; Min, Byung Sun

    2017-07-01

    Five new compounds, 10-oxomornigrol F (1), (7″R)-(-)-6-(7″-hydroxy-3″,8″-dimethyl-2″,8″-octadien-1″-yl)apigenin (2), ramumorin A (3), ramumorin B (4), and (4S,7S,8R)-trihydroxyoctadeca-5Z-enoic acid (5), together with 31 known compounds (6-36), were isolated from the twigs of Morus alba (Moraceae). The chemical structures of these compounds were established using spectroscopic analyses, 1D and 2D NMR, high-resolution electrospray ionization mass spectrometry (HRESIMS), and Mosher's methods. The anti-inflammatory activities of the compounds were evaluated by investigating their ability to inhibit lipopolysaccharide (LPS)-induced nitric oxide (NO) production in macrophage RAW 264.7 cells. Compounds 1, 2, 13, 17, 19, 25-28, and 32 showed inhibitory effects with IC 50 values ranging from 2.2 to 5.3μg/mL. Compounds 1, 2, 17, 25, and 32 reduced LPS-induced inducible nitric oxide synthase (iNOS) expression in a concentration-dependent manner. In addition, pretreating the cells with compound 1, 17, and 32 significantly suppressed LPS-induced expression of cyclooxygenase-2 (COX-2) protein. Copyright © 2017. Published by Elsevier B.V.

  3. Production of active charcoal and characteristic of volatile organic compounds in condensate

    International Nuclear Information System (INIS)

    Lalik, V.; Knoskova, L.

    2005-01-01

    In the last decade a production of charcoal and products from charcoal has been taking on an important position in a field of environmental technologies. Technological process of the production of charcoal is accompanied by formation of fluid and gaseous elements. These elements are ranked as pollutants from the legal point of view. There are mainly carbon dioxide and carbon monoxide and other oxide compounds from the chemical point of view. Particularly acetic acid, methanol, 2-furaldehyde. Then aliphatic alcohols, phenols, aldehydes, ketones, esters and other groups of substances. Law limits the quantity and concentration of these essentials emitted into the open air. This matter has to be taken care of during the production of charcoal. It is usually solved by condensation cooling and following burning gases and steams. Condensate is industrially processed or smaller technologies handle with it similar to taking care of wastewater. (authors)

  4. Antibacterial activities of the extracts, fractions and compounds from Dioscorea bulbifera

    Directory of Open Access Journals (Sweden)

    Kuete Victor

    2012-11-01

    Full Text Available Abstract Background Dioscorea bulbifera is an African medicinal plant used to treat microbial infections. In the present study, the methanol extract, fractions (DBB1 and DBB2 and six compounds isolated from the bulbils of D. bulbifera, namely bafoudiosbulbins A (1, B (2, C (3, F (4, G (5 and 2,7-dihydroxy-4-methoxyphenanthrene (6, were tested for their antimicrobial activities against Mycobacteria and Gram-negative bacteria involving multidrug resistant (MDR phenotypes expressing active efflux pumps. Methods The microplate alamar blue assay (MABA and the broth microdilution methods were used to determine the minimal inhibitory concentration (MIC and minimal bactericidal concentration (MBC of the above samples. Results The results of the MIC determinations indicated that when tested alone, the crude extract, fractions DBB1 and DBB2 as well as compounds 2 to 5 were able to prevent the growth of all the fifteen studied microorganisms, within the concentration range of 8 to 256 μg/mL. The lowest MIC value for the methanol extract and fractions (16 μg/mL was obtained with DBB1 and DBB2 on E, coli AG100A and DBB2 on Mycobacterium tuberculosis MTCS2. The lowest value for individual compounds (8 μg/mL was recorded with compound 3 on M. smegmatis and M. tuberculosis ATCC and MTCS2 strains respectively. The activity of the samples on many MDR bacteria such as Enterobacter aerogenes EA289, CM64, Klebsiella pneumoniae KP63 and Pseudomonas aeruginosa PA124 was better than that of chloramphenicol. When tested in the presence of the efflux pump inhibitor against MDR Gram-negative bacteria, the activity of most of the samples increased. MBC values not greater than 512 μg/mL were recorded on all studied microorganisms with fraction DBB2 and compounds 2 to 5. Conclusions The overall results of the present investigation provided evidence that the crude extract D. bulbifera as well as some of the compounds and mostly compounds 3 could be considered as potential

  5. Synthesis and Antiplatelet Activity of Antithrombotic Thiourea Compounds: Biological and Structure-Activity Relationship Studies

    Directory of Open Access Journals (Sweden)

    André Luiz Lourenço

    2015-04-01

    Full Text Available The incidence of hematological disorders has increased steadily in Western countries despite the advances in drug development. The high expression of the multi-resistance protein 4 in patients with transitory aspirin resistance, points to the importance of finding new molecules, including those that are not affected by these proteins. In this work, we describe the synthesis and biological evaluation of a series of N,N'-disubstituted thioureas derivatives using in vitro and in silico approaches. New designed compounds inhibit the arachidonic acid pathway in human platelets. The most active thioureas (compounds 3d, 3i, 3m and 3p displayed IC50 values ranging from 29 to 84 µM with direct influence over in vitro PGE2 and TXA2 formation. In silico evaluation of these compounds suggests that direct blockage of the tyrosyl-radical at the COX-1 active site is achieved by strong hydrophobic contacts as well as electrostatic interactions. A low toxicity profile of this series was observed through hemolytic, genotoxic and mutagenic assays. The most active thioureas were able to reduce both PGE2 and TXB2 production in human platelets, suggesting a direct inhibition of COX-1. These results reinforce their promising profile as lead antiplatelet agents for further in vivo experimental investigations.

  6. End-group-directed self-assembly of organic compounds useful for photovoltaic applications

    Science.gov (United States)

    Beaujuge, Pierre M.; Lee, Olivia P.; Yiu, Alan T.; Frechet, Jean M.J.

    2016-05-31

    The present invention provides for an organic compound comprising electron deficient unit covalently linked to two or more electron rich units. The present invention also provides for a device comprising the organic compound, such as a light-emitting diode, thin-film transistor, chemical biosensor, non-emissive electrochromic, memory device, photovoltaic cells, or the like.

  7. Active compounds from cyanobacteria and microalgae: properties and potential applications in biomedicine

    Directory of Open Access Journals (Sweden)

    Alexey Llopiz

    2016-05-01

    Full Text Available Cyanobacteria and microalgae are source of many chemicals substances with potential applications on biopharmaceutical industry. Many structures have been characterized in these organism, such as: peptides, proteins, carbohydrates, terpenoids, polyinsatured fatty acids, flavonoids, phenolic compounds, vitamins, porfirins and other organic substances. Chemicals structures of isolated compounds are diverse and it depends of microalgae habitats. Pharmacological activities located in microalgae are bactericides, immunomodulatory, antioxidants, cytoprotective, fungicides and antivirals. These properties may possible the potential treatment of many diseases including autoimmunes disorders, tumoral, and infectious process. In this review are presented and discussed some elements associated to chemical structure and biological activities around of compounds with potential uses as biopharmaceuticals.

  8. Volatile Organic Compound (VOC) Emissions from Dairy Cows and Their Waste

    Science.gov (United States)

    Shaw, S.; Holzinger, R.; Mitloehner, F.; Goldstein, A.

    2005-12-01

    Biogenic VOCs are typically defined as those directly emitted from plants, but approximately 6% of global net primary production is consumed by cattle that carry out enteric fermentation and then emit VOCs that could also be considered biogenic. Current regulatory estimates suggest that dairy cattle in central California emit VOCs at rates comparable to those from passenger vehicles in the region, and thus contribute significantly to the extreme non-attainment of ozone standards there. We report PTR-MS measurements of ammonia and VOCs, and cavity-enhanced-absorption gas analyzer (Los Gatos Research, Inc.) measurements of CH4, emitted from dairy cattle in various stages of pregnancy/lactation and their waste. Experiments were conducted in chambers at UC Davis that simulate freestall cow housing conditions. CH4 fluxes ranged from 125-374 lb/cow/year. The compounds with the highest fluxes from '3 cows+waste' treatments were: ammonia (1-18), methanol (0-2.3), acetone+propanal (0.2-0.7), dimethylsulfide (0-0.4), and mass 109 (likely ID = p-cresol; 0-0.3) in lb/cow/year. Mass 60 (likely ID = trimethylamine) and acetic acid were also abundant. There were 10s of additional compounds with detectable, but small, emissions. A few compounds that were likely emitted (i.e. ethanol, formaldehyde, and dimethylamine) were not quantified by the PTR-MS. The total flux for all measured organic gases (TOG = CH4 + PTR-MS VOCs(including acetone+propanal)) averaged 246±45 lb/cow/year for '3 cows+waste' treatments, and was dominated by methane (>98%). TOG flux for 'waste only' treatments averaged 1.1±0.1 lb/cow/year, and was instead dominated by VOC (>84%). The PTR-MS VOCs as a percent of TOG (0.6±0.2%) emitted from '3 cows+waste' treatments in chamber conditions was a factor of 10 smaller than that currently estimated by the California Air Resources Board. In addition, the ozone forming potentials of the most abundant VOCs are only about 10% those of typical combustion or plant

  9. Top emitting white OLEDs

    Energy Technology Data Exchange (ETDEWEB)

    Freitag, Patricia; Luessem, Bjoern; Leo, Karl [Technische Universitaet Dresden, Institut fuer Angewandte Photophysik, George-Baehr-Strasse 1, 01069 Dresden (Germany)

    2009-07-01

    Top emitting organic light emitting diodes (TOLEDs) provide a number of interesting opportunities for new applications, such as the opportunity to fabricate ITO-free devices by using opaque substrates. This makes it possible to manufacture low cost OLEDs for signage and lighting applications. A general top emitting device consists of highly reflecting metal contacts as anode and semitransparent cathode, the latter one for better outcouling reasons. In between several organic materials are deposited as charge transporting, blocking, and emission layers. Here, we show a top emitting white organic light emitting diode with silver electrodes arranged in a p-i-n structure with p- and n-doped charge transport layers. The centrical emission layer consists of two phosphorescent (red and green) and one fluorescent (blue) emitter systems separated by an ambipolar interlayer to avoid mutual exciton quenching. By adding an additional dielectric capping layer on top of the device stack, we achieve a reduction of the strong microcavity effects which appear due to the high reflection of both metal electrodes. Therefore, the outcoupled light shows broad and nearly angle-independent emission spectra, which is essential for white light emitting diodes.

  10. Monitoring of selected skin- and breath-borne volatile organic compounds emitted from the human body using gas chromatography ion mobility spectrometry (GC-IMS).

    Science.gov (United States)

    Mochalski, Paweł; Wiesenhofer, Helmut; Allers, Maria; Zimmermann, Stefan; Güntner, Andreas T; Pineau, Nicolay J; Lederer, Wolfgang; Agapiou, Agapios; Mayhew, Christopher A; Ruzsanyi, Veronika

    2018-02-15

    Human smuggling and associated cross-border crimes have evolved as a major challenge for the European Union in recent years. Of particular concern is the increasing trend of smuggling migrants hidden inside shipping containers or trucks. Therefore, there is a growing demand for portable security devices for the non-intrusive and rapid monitoring of containers to detect people hiding inside. In this context, chemical analysis of volatiles organic compounds (VOCs) emitted from the human body is proposed as a locating tool. In the present study, an in-house made ion mobility spectrometer coupled with gas chromatography (GC-IMS) was used to monitor the volatile moieties released from the human body under conditions that mimic entrapment. A total of 17 omnipresent volatile compounds were identified and quantified from 35 ion mobility peaks corresponding to human presence. These are 7 aldehydes (acrolein, 2-methylpropanal, 3-methylbutanal, 2-ethacrolein, n-hexanal, n-heptanal, benzaldehyde), 3 ketones (acetone, 2-pentanone, 4-methyl-2-pentanone), 5 esters (ethyl formate, ethyl propionate, vinyl butyrate, butyl acetate, ethyl isovalerate), one alcohol (2-methyl-1-propanol) and one organic acid (acetic acid). The limits of detection (0.05-7.2 ppb) and relative standard deviations (0.6-11%) should be sufficient for detecting these markers of human presence in field conditions. This study shows that GC-IMS can be used as a portable field detector of hidden or entrapped people. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. Anti-plasmodial activity of Dicoma tomentosa (Asteraceae) and identification of urospermal A-15-O-acetate as the main active compound

    Science.gov (United States)

    2012-01-01

    Background Natural products could play an important role in the challenge to discover new anti-malarial drugs. In a previous study, Dicoma tomentosa (Asteraceae) was selected for its promising anti-plasmodial activity after a preliminary screening of several plants traditionally used in Burkina Faso to treat malaria. The aim of the present study was to further investigate the anti-plasmodial properties of this plant and to isolate the active anti-plasmodial compounds. Methods Eight crude extracts obtained from D. tomentosa whole plant were tested in vitro against two Plasmodium falciparum strains (3D7 and W2) using the p-LDH assay (colorimetric method). The Peters’ four-days suppressive test model (Plasmodium berghei-infected mice) was used to evaluate the in vivo anti-plasmodial activity. An in vitro bioguided fractionation was undertaken on a dichloromethane extract, using preparative HPLC and TLC techniques. The identity of the pure compound was assessed using UV, MS and NMR spectroscopic analysis. In vitro cytotoxicity against WI38 human fibroblasts (WST-1 assay) and haemolytic activity were also evaluated for extracts and pure compounds in order to check selectivity. Results The best in vitro anti-plasmodial results were obtained with the dichloromethane, diethylether, ethylacetate and methanol extracts, which exhibited a high activity (IC50 ≤ 5 μg/ml). Hot water and hydroethanolic extracts also showed a good activity (IC50 ≤ 15 μg/ml), which confirmed the traditional use and the promising anti-malarial potential of the plant. The activity was also confirmed in vivo for all tested extracts. However, most of the active extracts also exhibited cytotoxic activity, but no extract was found to display any haemolytic activity. The bioguided fractionation process allowed to isolate and identify a sesquiterpene lactone (urospermal A-15-O-acetate) as the major anti-plasmodial compound of the plant (IC50 < 1 μg/ml against both 3D7 and W2 strains). This was also

  12. New Benzimidazole-1,2,4-Triazole Hybrid Compounds: Synthesis, Anticandidal Activity and Cytotoxicity Evaluation

    Directory of Open Access Journals (Sweden)

    Hülya Karaca Gençer

    2017-03-01

    Full Text Available Owing to the growing need for antifungal agents, we synthesized a new series 2-((5-(4-(5-substituted-1H-benzimidazol-2-ylphenyl-4-substituted-4H-1,2,4-triazol-3-ylthio-1-(substitutedphenylethan-1-one derivatives, which were tested against Candida species. The synthesized compounds were characterized and elucidated by FT-IR, 1H-NMR, 13C-NMR and HR-MS spectroscopies. The synthesized compounds were screened in vitro anticandidal activity against Candida species by broth microdiluation methods. In vitro cytotoxic effects of the final compounds were determined by MTT assay. Microbiological studies revealed that compounds 5m, 5o, 5r, 5t, 5y, 5ab, and 5ad possess a good antifungal profile. Compounds 5w was the most active derivative and showed comparable antifungal activity to those of reference drugs ketoconazole and fluconazole. Cytotoxicity evaluation of compounds 5m, 5o, 5r, 5w, 5y, 5ab and 5ad showed that compounds 5w and 5ad were the least cytotoxic agents. Effects of these two compounds against ergosterol biosynthesis were observed by LC-MS-MS method, which is based on quantification of ergosterol level in C. albicans. Compounds 5w and 5d inhibited ergosterol biosynthesis concentration dependently. A fluorescence microscopy study was performed to visualize effect of compound 5w against C. albicans at cellular level. It was determined that compound 5w has a membrane damaging effect, which may be related with inhibition of biosynthesis of ergosterol.

  13. Antifeedant compounds from three species of Apiaceae active against the field slug, Deroceras reticulatum (Muller).

    Science.gov (United States)

    Birkett, Michael A; Dodds, Catherine J; Henderson, Ian F; Leake, Lucy D; Pickett, John A; Selby, Martin J; Watson, Peter

    2004-03-01

    Extracts of volatiles from foliage of three plants in the Apiaceae, Conium maculatum L. (hemlock), Coriandrum sativum L. (coriander), and Petroselinum crispum Mill. (Nym.) (parsley), previously shown to exhibit antifeedant activity in assays with the field slug, Deroceras reticulatum (Muller) (Limacidae: Pulmonata), were studied further to identify the active components. Coupled gas chromatography-mass spectrometry (GC-MS) and neurophysiological assays using tentacle nerve preparations resulted in the identification of 11 active compounds from the three extracts. Wheat flour feeding bioassays were used to determine which of these compounds had the highest antifeedant activity. One of the most active compounds was the alkaloid gamma-coniceine, from C. maculatum. The role of potentially toxic alkaloids as semiochemicals and the potential for using such compounds as crop protection agents to prevent slug feeding damage is discussed.

  14. Production and characterization of surface-active compounds from Gordonia amicalis

    Directory of Open Access Journals (Sweden)

    Ani Beatriz Jackisch-Matsuura

    2014-02-01

    Full Text Available Two methods were used to make crude preparations of surface-active compounds (SACs produced by Gordonia amicalis grown on the medium containing 1% diesel oil. Using a 2:1 (v/v solution of chloroform:methanol for extraction, Type I SACs were isolated and shown to produce oil in water (O/W emulsions. Type II SACs were isolated by precipitation with ammonium sulfate and produced predominantly water in oil emulsions (W/O. The crude Type I and II preparations were able to produce a significant reduction in the surface tension of water; however, the crude Type II preparation had 10-25 fold higher emulsification activity than the Type I preparation. Both SAC preparations were analyzed by the TLC and each produced two distinct bands with Rf 0.44 and 0.62 and Rf 0.52 and 0.62, respectively. The partially purified SACs were characterized by the ESI(+-MS, FT-IR and NMR. In each one of these fractions, a mixture of 10 oligomers was found consisting of a series of compounds, with masses from 502 to 899, differing in molecular mass by a repeating unit of 44 Daltons. The mass spectra of these compounds did not appear to match other known biosurfactants and could represent a novel class of these compounds.

  15. Application of head-space solid-phase microextraction for the analysis of volatile metabolites emitted by Penicillium species

    DEFF Research Database (Denmark)

    Nilsson, Torben; Larsen, Thomas Ostenfeld; Montanarella, Luca

    1996-01-01

    Head-space solid-phase microextraction (HS-SPME) has been used to collect volatile organic compounds (VOCs) emitted from fungi of the genus Penicillium. Gas chromatography combined with mass spectrometry (GC-MS) was employed for the analysis of the profiles of volatile metabolites characteristic...

  16. Adsorption of Volatile Organic Compounds from Aqueous Solution by Granular Activated Carbon in Batch System

    International Nuclear Information System (INIS)

    Zeinali, F.; Ghoreyshi, A. A.; Najafpour, G.

    2011-01-01

    Chlorinated hydrocarbons and aromatics are the major volatile organic compounds that contaminate the ground water and industrial waste waters. The best way to overcome this problem is to recover the dissolved compounds in water. In order to evaluate the potential ability of granular activated carbon for recovery of volatile organic compounds from water, the equilibrium adsorption was investigated. This study deals with the adsorption of dichloromethane as a typical chlorinated volatile organic compound and toluene as the representative of aromatic volatile organic compounds on a commercial granular activated carbon. The adsorption isotherms of these two volatile organic compounds on granular activated carbon were measured at three different temperatures, toluene at 293, 303 and 313 K and dichloromethane at 298, 303 and 313 K within their solubility concentration range in water. The maximum adsorption capacity of dichloromethane and toluene adsorption by granular activated carbon was 4 and 0.2 mol/Kg-1, respectively. The experimental data obtained were correlated with different adsorption isotherm models. The Langmuir model was well adapted to the description of dichloromethane adsorption on granular activated carbon at all three temperatures, while the adsorption of toluene on granular activated carbon was found to be well described by the Langmuir-BET hybrid model at all three temperatures. The heat of adsorption was also calculated based on the thermodynamic equation of Clausius Clapeyron, which indicates the adsorption process is endothermic for both compounds.

  17. External tandem target system for efficient production of short-lived positron emitting radionuclides

    International Nuclear Information System (INIS)

    Koh, K.; Dwyer, J.; Finn, R.; Sheh, Y.; Sinnreich, J.; Wooten, T.

    1983-01-01

    Recent developments in radiopharmaceutical chemistry allow the incorporation of short-lived, positron-emitting radionuclides into a variety of compounds which when used with a positron emission tomograph provide a means of monitoring physiological disorders by a standard technique. To effectively meet the increased ''in-house'' clinical demands while maintaining a production schedule, a tandem target was designed and has been installed for the simultaneous ''on-line'' preparation of oxygen-15 labelled compounds such as CO 2 15 , H 2 O 15 ; and nitrogen-13 labelled compounds such as 13 NH 3 , 13 N 2 O, and 13 N 2 . The processing time required for the synthesis of the nitrogen-13 products as compared to the essentially instantaneous formation of oxygen-15 labelled compounds has provided the necessary time delay for clinical utilization. The characterisitcs of this external tandem target system as well as the automation for the dual processing are presented

  18. Monte Carlo Simulation for Statistical Decay of Compound Nucleus

    Directory of Open Access Journals (Sweden)

    Chadwick M.B.

    2012-02-01

    Full Text Available We perform Monte Carlo simulations for neutron and γ-ray emissions from a compound nucleus based on the Hauser-Feshbach statistical theory. This Monte Carlo Hauser-Feshbach (MCHF method calculation, which gives us correlated information between emitted particles and γ-rays. It will be a powerful tool in many applications, as nuclear reactions can be probed in a more microscopic way. We have been developing the MCHF code, CGM, which solves the Hauser-Feshbach theory with the Monte Carlo method. The code includes all the standard models that used in a standard Hauser-Feshbach code, namely the particle transmission generator, the level density module, interface to the discrete level database, and so on. CGM can emit multiple neutrons, as long as the excitation energy of the compound nucleus is larger than the neutron separation energy. The γ-ray competition is always included at each compound decay stage, and the angular momentum and parity are conserved. Some calculations for a fission fragment 140Xe are shown as examples of the MCHF method, and the correlation between the neutron and γ-ray is discussed.

  19. Uptake and transport of positron-emitting tracer in plants

    Energy Technology Data Exchange (ETDEWEB)

    Kume, Tamikazu; Matsuhashi, Shinpei; Shimazu, Masamitsu [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; and others

    1997-03-01

    The transport of a positron-emitting isotope introduced into a plant was dynamically followed by a special observation apparatus called `Positron-Emitting Tracer Imaging System`. In the system, annihilation {gamma}-rays from the positron emitter are detected with two planer detectors (5 x 6 cm square). The water containing ca. 5 MBq/ml of {sup 18}F was fed to the cut stem of soybean for 2 min and then the images of tracer activity were recorded for 30 - 50 min. When the midrib of a leaf near the petiole was cut just before measurement, the activity in the injured leaf was decreased but detected even at the apex. This result suggests that the damaged leaf recovered the uptake of water through the lamina. Maximum tracer activities in leaves of unirradiated plant were observed within 10 min, whereas those of irradiated plant at 100 Gy were observed after over 25 min. The final activity of irradiated plant after 30 min was lower than that of unirradiated plant. In case of beans, there was a difference in the absorption behavior of the {sup 18}F-labeled water between unirradiated and irradiated samples. These results show that the system is effective to observe the uptake and transportation of water containing positron emitting tracer for the study of damage and recovery functions of plants. (author)

  20. Characterization of key aroma-active compounds in lychee (Litchi chinensis Sonn.

    Directory of Open Access Journals (Sweden)

    Shi Feng

    2018-04-01

    Full Text Available Volatile compounds in ‘Sweetheart’ lychee were examined using gas chromatography-olfactometry/mass spectrometry (GC-O/MS. Solvent assisted flavor evaporation (SAFE technique was used to identify the aroma-active compounds in lychee. Further characterization of the most important odorants in ‘Sweetheart’ lychee was achieved using aroma extract dilution analysis (AEDA. Thirty-one key aroma-active odorants were identified in the flavor dilution (FD factor range of 2–1024. Methional (cooked potato and geraniol (sweet, floral exhibited the highest FD factors of 1024 and 512, respectively, these were followed by furaneol (sweet, caramel, nerol (floral, sweet, dimethyl trisulfide (DMTS (preserved vegetable, sulfury, linalool (floral, (E,Z-2,6 nonadienal (cucumber and nerolidol (metalic, sesame oil. Furthermore, the flavor profile of ‘Sweetheart’ lychee was described by sensory analysis. Floral, tropical fruit, peach/apricot and honey were scored with relatively high scores for each aroma attribute. The sweetness rating was the highest score among all the attributes. Keywords: AEDA, Aroma-active compounds, GC-MS/O, SAFE, Sensory analysis

  1. Synthesis and Antiplasmodial Activity of 2-(4-Methoxyphenyl-4-Phenyl-1,10-Phenanthroline Derivative Compounds

    Directory of Open Access Journals (Sweden)

    Nazudin

    2012-08-01

    Full Text Available A unique of synthetic methods was employed to prepare 2-(4-methoxyphenyl-4-phenyl-1,10-phenanthroline (5 derivatives from 4-methoxy-benzaldehyde (1, acetophenone (2, and 8-aminoquinoline (4 with aldol condensation and cyclization reactions. The derivatives were tested through antiplasmodial test. The synthesis of derivatives compound 5 was conducted in three steps. The 3-(4-methoxyphenyl-1-phenylpropenone 3 was synthesized through aldol condensation of 1 and 2 which has a yield of 96.42%. The compound 5 was synthesized through cyclization of compound 4 and 3 with 84.55% yield. The derivative of compound 5 was synthesized from compound 5 using DMS and DES reagents which refluxed for 21 and 22 h, to produce (1-N-methyl-9-(4-methoxyphenyl-7-phenyl-1,10-phenanthrolinium sulfate (6 and (1-N-ethyl-9-(4-methoxyphenyl-7-phenyl-1,10-phenanthrolinium sulfate (7 with 91.42 and 86.36% yields, respectively. Results of in vitro testing of antiplasmodial activity of compound 5 derivatives (i.e., compound 6 and 7 against chloroquine-resistant P. falciparum FCR3 strain showed that compound 7 had higher antimalarial activity than compounds 5 and 6. Whereas, results of in vitro testing against chloroquine-sensitive P. falciparum D10 strain showed that compound 6 has higher antimalarial activity than compounds 5 and 7.

  2. Efficient discovery of responses of proteins to compounds using active learning

    Science.gov (United States)

    2014-01-01

    Background Drug discovery and development has been aided by high throughput screening methods that detect compound effects on a single target. However, when using focused initial screening, undesirable secondary effects are often detected late in the development process after significant investment has been made. An alternative approach would be to screen against undesired effects early in the process, but the number of possible secondary targets makes this prohibitively expensive. Results This paper describes methods for making this global approach practical by constructing predictive models for many target responses to many compounds and using them to guide experimentation. We demonstrate for the first time that by jointly modeling targets and compounds using descriptive features and using active machine learning methods, accurate models can be built by doing only a small fraction of possible experiments. The methods were evaluated by computational experiments using a dataset of 177 assays and 20,000 compounds constructed from the PubChem database. Conclusions An average of nearly 60% of all hits in the dataset were found after exploring only 3% of the experimental space which suggests that active learning can be used to enable more complete characterization of compound effects than otherwise affordable. The methods described are also likely to find widespread application outside drug discovery, such as for characterizing the effects of a large number of compounds or inhibitory RNAs on a large number of cell or tissue phenotypes. PMID:24884564

  3. Antimicrobial and acetylcholinesterase inhibitory activities of Buddleja salviifolia (L.) Lam. leaf extracts and isolated compounds.

    Science.gov (United States)

    Pendota, S C; Aderogba, M A; Ndhlala, A R; Van Staden, J

    2013-07-09

    Buddleja salviifolia leaves are used for the treatment of eye infections and neurodegenerative conditions by various tribes in South Africa. This study was designed to isolate the phenolic constituents from the leaf extracts of Buddleja salviifolia and evaluate their antimicrobial and acetylcholinesterase (AChE) activities. Three phenolic compounds were isolated from the ethyl acetate fraction of a 20% aqueous methanol leaf extract of Buddleja salviifolia using Sephadex LH-20 and silica gel columns. Structure elucidation of the isolated compounds was carried out using spectroscopic techniques: mass spectrometry (ESI-TOF-MS) and NMR (1D and 2D). The extracts and isolated compounds were evaluated for antimicrobial and acetylcholinesterase activities using the microdilution technique. The bacteria used for the antimicrobial assays were Gram-positive Bacillus subtilis and Staphylococcus aureus and Gram-negative Escherichia coli and Klebsiella pneumoniae. The isolated compounds were characterized as: 4'-hydroxyphenyl ethyl vanillate (1) a new natural product, acteoside (2) and quercetin (3). The crude extract, fractions and the isolated compounds from the leaves of the plant exhibited a broad spectrum of antibacterial activity. The EtOAc fraction exhibited good activity against Bacillus subtilis and Staphylococcus aureus with MIC values ranging from 780.0 to 390.0 µg/mL. Isolated compound 2 exhibited good activity against Staphylococcus aureus with an MIC value of 62.5 µg/mL. The hexane and DCM fractions of leaves showed the best activity against Candida albicans with MIC and MFC values of 390.0 µg/mL. In the AChE inhibitory test, among the tested extracts, the hexane fraction was the most potent with an IC50 value of 107.4 µg/mL, whereas for the isolated compounds, it was compound (3) (quercetin) with an IC50 value of 66.8 µg/mL. Activities demonstrated by the extracts and isolated compounds support the ethnopharmacological use of Buddleja salviifolia against eye

  4. Synthesis and anti-lung cancer activity of a novel arsenomolybdate compound

    Science.gov (United States)

    Zhu, Tian-Tian; Wang, Juan; Chen, Song-Hu

    2017-12-01

    The new compound based on Wells-Dawson-type arsenomolybdate: [{Cu10(pz)11Cl4}{As2IIIAs2VMo6VMo12VIO62}]·H2O (1) has been hydrothermally synthesized and characterized by single-crystal X-ray diffraction analysis, X-ray powder diffraction (XRPD), XPS spectroscopy and thermogravimetric analysis (TG). Compound 1 is consisted of two As caps Wells-dawson-type arsenomolybdate and {Cu10(py)11} complexes by chloride bridge. In addition, the antitumor effects of the title compound 1 were studied on three human lung cancer cells (A549, SK-LU-1 and SW1573). The results showed that compared with the positive reference drug carboplatin, compound 1 displayed efficient antitumor activity.

  5. Comparison of Active Vitamin D Compounds and a Calcimimetic in Mineral Homeostasis

    OpenAIRE

    Nguyen-Yamamoto, Loan; Bolivar, Isabel; Strugnell, Stephen A.; Goltzman, David

    2010-01-01

    The differential effects between cinacalcet and active vitamin D compounds on parathyroid function, mineral metabolism, and skeletal function are incompletely understood. Here, we studied cinacalcet and active vitamin D compounds in mice expressing the null mutation for Cyp27b1, which encodes 25-hydroxyvitamin D-1α-hydroxylase, thereby lacking endogenous 1,25-dihydroxyvitamin D3 [1,25(OH)2D3]. Vehicle-treated mice given high dietary calcium had hypocalcemia, hypophosphatemia, and marked secon...

  6. Molecular docking for thrombolytic activity of some isolated compounds from Clausena lansium.

    Directory of Open Access Journals (Sweden)

    Arkajyoti Paul

    2017-03-01

    Full Text Available Clausena lansium (Family- Rutaceae is commonly known as wampee, is found in fallow lands throughout Bangladesh. Our aim of the study to performed molecular docking studies to identify potential binding affinities of the phytocompounds from Clausena lansium, namely Clausemarin B, Clausenaline C, Clausenaline E, Murrayanine, vanillic acid and Xanthotoxol for searching of lead molecule for thrombolytic activity. A wide range of docking score found during molecular docking by Schrodinger. Clausemarin B , Clausenaline C , Clausenaline E, Murrayanine , vanillic acid and Xanthotoxol showed the docking score -6.926, -4.041, -4.889 , -4.356, -3.007 and -5.816 respectively. Among all the compounds Clausemarin B showed the best docking score. So, Clausemarin B is the best compounds for thrombolytic activity, as it possessed the best value in Molecular docking. Further in vivo investigation need to identify the thrombolytic activity of isolated compounds from Clausena lansium.

  7. Phenolic Compounds from the Leaves of Stewartia pseudocamellia Maxim. and their Whitening Activities.

    Science.gov (United States)

    Roh, Hyun Jung; Noh, Hye-Ji; Na, Chun Su; Kim, Chung Sub; Kim, Ki Hyun; Hong, Cheol Yi; Lee, Kang Ro

    2015-05-01

    The half-dried leaves of Stewartia. pseudocamellia were extracted with hot water (SPE) and partitioned with n-hexane (SPEH), dichloromethane (SPED), and ethyl acetate (SPEE) successively. SPE and SPEE showed significant inhibitory effects against melanogenesis and tyrosinase activities. By bioassay-guided isolation, ten phenolic compounds were isolated by column chromatography from SPEE. The whitening effect of the isolated compounds from SPEE were tested for the inhibitory activities against melanogenesis using B16 melanoma cells, in vitro inhibition of tyrosinase, and L-3,4-dihydorxy-indole-2-carboxylic acid (L-DOPA) auto-oxidation assay. A cytotoxic activity assay was done to examine the cellular toxicity in Raw 264.7 macrophage cells. Of the compounds isolated, gallic acid and quercetin revealed significant inhibitory activities against melanogenesis compared to arbutin. In particular, quercetin exhibited similar inhibitory activities against tyrosinase and L-DOPA oxidation without cytotoxicity. These results suggested that SPE could be used as a potential source of natural skin-whitening material in cosmetics as well as in food products.

  8. Active Compound of Zingiber Cassumunar Roxb. Down-Regulates ...

    African Journals Online (AJOL)

    MMPs activities in the culture media were analyzed by zymographic techniques. Dexamethasone was used as the positive control. It was found that compound D at the concentration of 10 - 100 µM significantly decreased the mRNA expressions of MMP-1, -2, -3, and -13 which was induced by IL-1ß (P<0.05) concomitantly ...

  9. Electrochemical screening of biomembrane-active compounds in water

    Energy Technology Data Exchange (ETDEWEB)

    Mohamadi, Shahrzad, E-mail: cmsm@leeds.ac.uk; Tate, Daniel J.; Vakurov, Alexander; Nelson, Andrew

    2014-02-01

    Graphical abstract: - Highlights: • Analytical technology application with improvement allowing for on-line high-throughput water toxin screening is presented. • Compound classes of related structure and shape interact with DOPC coated Pt/Hg with a class specific response. • Predecessor membrane system proved as fragile, complex and for environmental application incompatible. - Abstract: Interactions of biomembrane-active compounds with phospholipid monolayers on microfabricated Pt/Hg electrodes in an on-line high throughput flow system are demonstrated by recording capacitance current peak changes as rapid cyclic voltammograms (RCV). Detection limits of the compounds’ effects on the layer have been estimated from the data. Compounds studied include steroids, polycyclic aromatic hydrocarbons, tricyclic antidepressants and tricyclic phenothiazines. The results show that the extent and type of interaction depends on the—(a) presence and number of aromatic rings and substituents, (b) presence and composition of side chains and, (c) molecular shape. Interaction is only indirectly related to compound hydrophobicity. For a selection of tricyclic antidepressants and tricyclic phenothiazines the detection limit in water is related to their therapeutic normal threshold. The sensing assay has been tested in the presence of humic acid as a potential interferent and in a tap water matrix. The system can be applied to the screening of putative hazardous substances and pharmaceuticals allowing for early detection thereof in the water supply. The measurements are made in real time which means that potentially toxic compounds are detected rapidly within <10 min per assay. This technology will contribute greatly to environment safety and health.

  10. Electrochemical screening of biomembrane-active compounds in water

    International Nuclear Information System (INIS)

    Mohamadi, Shahrzad; Tate, Daniel J.; Vakurov, Alexander; Nelson, Andrew

    2014-01-01

    Graphical abstract: - Highlights: • Analytical technology application with improvement allowing for on-line high-throughput water toxin screening is presented. • Compound classes of related structure and shape interact with DOPC coated Pt/Hg with a class specific response. • Predecessor membrane system proved as fragile, complex and for environmental application incompatible. - Abstract: Interactions of biomembrane-active compounds with phospholipid monolayers on microfabricated Pt/Hg electrodes in an on-line high throughput flow system are demonstrated by recording capacitance current peak changes as rapid cyclic voltammograms (RCV). Detection limits of the compounds’ effects on the layer have been estimated from the data. Compounds studied include steroids, polycyclic aromatic hydrocarbons, tricyclic antidepressants and tricyclic phenothiazines. The results show that the extent and type of interaction depends on the—(a) presence and number of aromatic rings and substituents, (b) presence and composition of side chains and, (c) molecular shape. Interaction is only indirectly related to compound hydrophobicity. For a selection of tricyclic antidepressants and tricyclic phenothiazines the detection limit in water is related to their therapeutic normal threshold. The sensing assay has been tested in the presence of humic acid as a potential interferent and in a tap water matrix. The system can be applied to the screening of putative hazardous substances and pharmaceuticals allowing for early detection thereof in the water supply. The measurements are made in real time which means that potentially toxic compounds are detected rapidly within <10 min per assay. This technology will contribute greatly to environment safety and health

  11. Antimalarial activity of compounds comprising a primary benzene sulfonamide fragment.

    Science.gov (United States)

    Andrews, Katherine T; Fisher, Gillian M; Sumanadasa, Subathdrage D M; Skinner-Adams, Tina; Moeker, Janina; Lopez, Marie; Poulsen, Sally-Ann

    2013-11-15

    Despite the urgent need for effective antimalarial drugs with novel modes of action no new chemical class of antimalarial drug has been approved for use since 1996. To address this, we have used a rational approach to investigate compounds comprising the primary benzene sulfonamide fragment as a potential new antimalarial chemotype. We report the in vitro activity against Plasmodium falciparum drug sensitive (3D7) and resistant (Dd2) parasites for a panel of fourteen primary benzene sulfonamide compounds. Our findings provide a platform to support the further evaluation of primary benzene sulfonamides as a new antimalarial chemotype, including the identification of the target of these compounds in the parasite. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Calculation of the gamma-dose rate from a continuously emitted plume

    International Nuclear Information System (INIS)

    Huebschmann, W.; Papadopoulos, D.

    1975-06-01

    A computer model is presented which calculates the long term gamma dose rate caused by the radioactive off-gas continuously emitted from a stack. The statistical distribution of the wind direction and velocity and of the stability categories is taken into account. The emitted activity, distributed in the atmosphere according to this statistics, is assumed to be concentrated at the mesh points of a three-dimensional grid. The grid spacing and the integration limits determine the accuracy as well as the computer time needed. When calculating the dose rate in a given wind direction, the contribution of the activity emitted into the neighbouring sectors is evaluated. This influence is demonstrated in the results, which are calculated with a error below 3% and compared to the dose rate distribution curves of the submersion model and the model developed by K.J. Vogt. (orig.) [de

  13. Bioactive Compounds and Antioxidant Activity in Different Grafted Varieties of Bell Pepper

    Directory of Open Access Journals (Sweden)

    Celia Chávez-Mendoza

    2015-06-01

    Full Text Available Grafting favors the presence of bioactive compounds in the bell pepper, but many species and varieties have not yet been analyzed in this sense, including commonly grafted varieties. The aim of the present study is to characterize the content in β-carotenes, vitamin C, lycopene, total phenols, and the antioxidant activity of bell pepper (Capsicum annum L. using the cultivar/rootstock combinations: Jeanette/Terrano (yellow, Sweet/Robusto (green, Fascinato/Robusto (red, Orangela/Terrano (orange, and Fascinato/Terrano (red. The plants were grown in a net-shading system and harvested on three sampling dates of the same crop cycle. The results show statistical differences (p ≤ 0.05 between cultivar/rootstock combinations and sampling dates for the content in bioactive compounds and antioxidant activity. Fascinato/Robusto presented the highest concentration of lycopene and total phenols as well as the greatest antioxidant activity of all cultivar/rootstock combinations evaluated. In addition, it was found that the best sampling time for the peppers to have the highest concentrations of bioactive compounds and antioxidant activity was September.

  14. An optical and electrical study of full thermally activated delayed fluorescent white organic light-emitting diodes

    OpenAIRE

    Pereira, Daniel de Sa; dos Santos, Paloma L.; Ward, Jonathan S.; Data, Przemyslaw; Okazaki, Masato; Takeda, Youhei; Minakata, Satoshi; Bryce, Martin R.; Monkman, Andrew P.

    2017-01-01

    We report on the engineering of full thermally activated delayed fluorescence – based white organic light emitting diodes (W-OLEDs) composed of three emitters (2,7-bis(9,9-dimethyl-acridin-10-yl)-9,9-dimethylthioxanthene-S,S-dioxide (DDMA-TXO2), 2,7-bis(phenoxazin-10-yl)-9,9-dimethylthioxanthene-S,S-dioxide (DPO-TXO2) and 3,11-di(10H-phenoxazin-10-yl)dibenzo[a,j]phenazine (POZ-DBPHZ) in two different hosts. By controlling the device design through the study of the emission of DDMA-TXO2 and DP...

  15. NPACT: Naturally Occurring Plant-based Anti-cancer Compound-Activity-Target database.

    Science.gov (United States)

    Mangal, Manu; Sagar, Parul; Singh, Harinder; Raghava, Gajendra P S; Agarwal, Subhash M

    2013-01-01

    Plant-derived molecules have been highly valued by biomedical researchers and pharmaceutical companies for developing drugs, as they are thought to be optimized during evolution. Therefore, we have collected and compiled a central resource Naturally Occurring Plant-based Anti-cancer Compound-Activity-Target database (NPACT, http://crdd.osdd.net/raghava/npact/) that gathers the information related to experimentally validated plant-derived natural compounds exhibiting anti-cancerous activity (in vitro and in vivo), to complement the other databases. It currently contains 1574 compound entries, and each record provides information on their structure, manually curated published data on in vitro and in vivo experiments along with reference for users referral, inhibitory values (IC(50)/ED(50)/EC(50)/GI(50)), properties (physical, elemental and topological), cancer types, cell lines, protein targets, commercial suppliers and drug likeness of compounds. NPACT can easily be browsed or queried using various options, and an online similarity tool has also been made available. Further, to facilitate retrieval of existing data, each record is hyperlinked to similar databases like SuperNatural, Herbal Ingredients' Targets, Comparative Toxicogenomics Database, PubChem and NCI-60 GI(50) data.

  16. NPACT: Naturally Occurring Plant-based Anti-cancer Compound-Activity-Target database

    Science.gov (United States)

    Mangal, Manu; Sagar, Parul; Singh, Harinder; Raghava, Gajendra P. S.; Agarwal, Subhash M.

    2013-01-01

    Plant-derived molecules have been highly valued by biomedical researchers and pharmaceutical companies for developing drugs, as they are thought to be optimized during evolution. Therefore, we have collected and compiled a central resource Naturally Occurring Plant-based Anti-cancer Compound-Activity-Target database (NPACT, http://crdd.osdd.net/raghava/npact/) that gathers the information related to experimentally validated plant-derived natural compounds exhibiting anti-cancerous activity (in vitro and in vivo), to complement the other databases. It currently contains 1574 compound entries, and each record provides information on their structure, manually curated published data on in vitro and in vivo experiments along with reference for users referral, inhibitory values (IC50/ED50/EC50/GI50), properties (physical, elemental and topological), cancer types, cell lines, protein targets, commercial suppliers and drug likeness of compounds. NPACT can easily be browsed or queried using various options, and an online similarity tool has also been made available. Further, to facilitate retrieval of existing data, each record is hyperlinked to similar databases like SuperNatural, Herbal Ingredients’ Targets, Comparative Toxicogenomics Database, PubChem and NCI-60 GI50 data. PMID:23203877

  17. Optimization of freeform lightpipes for light-emitting-diode projectors.

    Science.gov (United States)

    Fournier, Florian; Rolland, Jannick

    2008-03-01

    Standard nonimaging components used to collect and integrate light in light-emitting-diode-based projector light engines such as tapered rods and compound parabolic concentrators are compared to optimized freeform shapes in terms of transmission efficiency and spatial uniformity. We show that the simultaneous optimization of the output surface and the profile shape yields transmission efficiency within the étendue limit up to 90% and spatial uniformity higher than 95%, even for compact sizes. The optimization process involves a manual study of the trends for different shapes and the use of an optimization algorithm to further improve the performance of the freeform lightpipe.

  18. Influence of organic nitro-compounds and of surface active compounds on the inverse voltametric determination of cadmium, lead and copper

    Energy Technology Data Exchange (ETDEWEB)

    Wahdat, F; Neeb, R

    1983-12-01

    The influence of surface active agents and of organic nitro-compounds alone and in combination on the potentiometric stripping analysis and anodic-stripping differential-pulse-polarography of Cd, Pb and Cu is investigated. In some cases PSA offers advantages for the determination of these elements in the presence of organic nitro-compounds in comparison with differential pulse-polarography.

  19. Synergistic anti-Campylobacter jejuni activity of fluoroquinolone and macrolide antibiotics with phenolic compounds

    Science.gov (United States)

    Oh, Euna; Jeon, Byeonghwa

    2015-01-01

    The increasing resistance of Campylobacter to clinically important antibiotics, such as fluoroquinolones and macrolides, is a serious public health problem. The objective of this study is to investigate synergistic anti-Campylobacter jejuni activity of fluoroquinolones and macrolides in combination with phenolic compounds. Synergistic antimicrobial activity was measured by performing a checkerboard assay with ciprofloxacin and erythromycin in the presence of 21 phenolic compounds. Membrane permeability changes in C. jejuni by phenolic compounds were determined by measuring the level of intracellular uptake of 1-N-phenylnaphthylamine (NPN). Antibiotic accumulation assays were performed to evaluate the level of ciprofloxacin accumulation in C. jejuni. Six phenolic compounds, including p-coumaric acid, sinapic acid, caffeic acid, vanillic acid, gallic acid, and taxifolin, significantly increased the susceptibility to ciprofloxacin and erythromycin in several human and poultry isolates. The synergistic antimicrobial effect was also observed in ciprofloxacin- and erythromycin-resistant C. jejuni strains. The phenolic compounds also substantially increased membrane permeability and antibiotic accumulation in C. jejuni. Interestingly, some phenolic compounds, such as gallic acid and taxifolin, significantly reduced the expression of the CmeABC multidrug efflux pump. Phenolic compounds increased the NPN accumulation in the cmeB mutant, indicating phenolic compounds may affect the membrane permeability. In this study, we successfully demonstrated that combinational treatment of C. jejuni with antibiotics and phenolic compounds synergistically inhibits C. jejuni by impacting both antimicrobial influx and efflux. PMID:26528273

  20. Vacuum Deposited Organic Light Emitting Devices on Flexible Substrates

    National Research Council Canada - National Science Library

    Forrest, Stephen

    2002-01-01

    The objective of this eight year program was to demonstrate both passive and active matrix, flexible, small scale displays based on small molecular weight organic light emitting device (OLED) technology...

  1. Evaluation of Biologically Active Compounds from Calendula officinalis Flowers using Spectrophotometry

    Directory of Open Access Journals (Sweden)

    Butnariu Monica

    2012-04-01

    Full Text Available Abstract Background This study aimed to quantify the active biological compounds in C. officinalis flowers. Based on the active principles and biological properties of marigolds flowers reported in the literature, we sought to obtain and characterize the molecular composition of extracts prepared using different solvents. The antioxidant capacities of extracts were assessed by using spectrophotometry to measure both absorbance of the colorimetric free radical scavenger 2,2-diphenyl-1-picrylhydrazyl (DPPH as well as the total antioxidant potential, using the ferric reducing power (FRAP assay. Results Spectrophotometric assays in the ultraviolet-visible (UV-VIS region enabled identification and characterization of the full range of phenolic and flavonoids acids, and high-performance liquid chromatography (HPLC was used to identify and quantify phenolic compounds (depending on the method of extraction. Methanol ensured more efficient extraction of flavonoids than the other solvents tested. Antioxidant activity in methanolic extracts was correlated with the polyphenol content. Conclusions The UV-VIS spectra of assimilator pigments (e.g. chlorophylls, polyphenols and flavonoids extracted from the C. officinalis flowers consisted in quantitative evaluation of compounds which absorb to wavelengths broader than 360 nm.

  2. Pulse seed germination improves antioxidative activity of phenolic compounds in stripped soybean oil-in-water emulsions.

    Science.gov (United States)

    Xu, Minwei; Jin, Zhao; Peckrul, Allen; Chen, Bingcan

    2018-06-01

    The purpose of this study was to investigate antioxidative activity of phenolic compounds extracted from germinated pulse seed including chickpeas, lentils and yellow peas. Phenolic compounds were extracted at different germination time and total phenolic content was examined by Folin Ciocalteu's reaction. Antioxidative activity of extracts was characterized by in vitro assay including 2, 2-diphenyl-1-picrylhydrazyl radical scavenging capacity (DPPH), oxygen radical absorbance capacity (ORAC), iron-binding assay, and in stripped soybean oil-in-water emulsions. The results suggested that germination time is critical for phenolic compounds production. The form variation of phenolic compounds influenced the antioxidative activity of phenolic compounds both in vitro assay and in emulsion systems. Soluble bound phenolic compounds showed higher antioxidative ability in emulsion system with the order of chickpea > yellow pea > lentil. On the basis of these results, soluble bound phenolic compounds may be considered as a promising natural antioxidant to prevent lipid oxidation in foods. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. Volatile compound diversity and conserved alarm behaviour in Triatoma dimidiata.

    Science.gov (United States)

    May-Concha, Irving; Rojas, Julio C; Cruz-López, Leopoldo; Ibarra-Cerdeña, Carlos N; Ramsey, Janine M

    2015-02-06

    Triatoma dimidiata (Latreille) is a key vector complex of Trypanosoma cruzi, etiologic agent of Chagas disease, as it spans North, Central, and South America. Although morphological and genetic studies clearly indicate existence of at least five clades within the species, there has been no robust or systematic revision, or appropriate nomenclature change for species within the complex. Three of the clades (haplogroups) are distributed in Mexico, and recent evidence attests to dispersal of clades across previously "presumed" monotypic geographic regions. Evidence of niche conservatism among sister species of this complex suggests that geographic dispersal is possible for non-sympatric populations, although no information is available on the behavioural aspects of potential interclade interactions, for instance whether differentiation of chemical signaling or response to these signals could impede communication among the haplogroups. Volatiles emitted by disturbed bugs, Brindley's (BGs), and metasternal (MGs) glands were identified using solid-phase micro-extraction (SPME) and gas chromatography coupled mass spectrometry (GC-MS). Volatile compounds emitted by BGs and MGs, and those secreted by disturbed nymphs and adults, of the three Mexican T. dimidiata haplogroups were tested for avoidance behaviour by conspecific nymphs and adults using an olfactometer. Triatoma dimidiata haplogroups all have three age-related alarm responses: absence of response by early stage nymphs, stage-specific response by 4-5th stage nymphs, and a shared 4-5th nymph and adult response to adult compounds. Disturbed bugs released 15 to 24 compounds depending on the haplogroup, among which were three pyrazines, the first report of these organoleptics in Triatominae. Isobutyric acid from BGs was the most abundant molecule in the response in all haplogroups, in addition to 15 (h1) to 21 (h2 and h3) MG compounds. Avoidance behaviour of disturbed bugs and volatiles emitted by BGs were haplogroup

  4. Mass and number size distributions of emitted particulates at five important operation units in a hazardous industrial waste incineration plant.

    Science.gov (United States)

    Lin, Chi-Chi; Huang, Hsiao-Lin; Hsiao, Wen-Yuan

    2016-01-01

    Past studies indicated particulates generated by waste incineration contain various hazardous compounds. The aerosol characteristics are very important for particulate hazard control and workers' protection. This study explores the detailed characteristics of emitted particulates from each important operation unit in a rotary kiln-based hazardous industrial waste incineration plant. A dust size analyzer (Grimm 1.109) and a scanning mobility particle sizer (SMPS) were used to measure the aerosol mass concentration, mass size distribution, and number size distribution at five operation units (S1-S5) during periods of normal operation, furnace shutdown, and annual maintenance. The place with the highest measured PM10 concentration was located at the area of fly ash discharge from air pollution control equipment (S5) during the period of normal operation. Fine particles (PM2.5) constituted the majority of the emitted particles from the incineration plant. The mass size distributions (elucidated) made it clear that the size of aerosols caused by the increased particulate mass, resulting from work activities, were mostly greater than 1.5 μm. Whereas the number size distributions showed that the major diameters of particulates that caused the increase of particulate number concentrations, from work activities, were distributed in the sub micrometer range. The process of discharging fly ash from air pollution control equipment can significantly increase the emission of nanoparticles. The mass concentrations and size distributions of emitted particulates were different at each operation unit. This information is valuable for managers to take appropriate strategy to reduce the particulate emission and associated worker exposure.

  5. Phytochemical Analysis, Identification and Quantification of Antibacterial Active Compounds in Betel Leaves, Piper betle Methanolic Extract.

    Science.gov (United States)

    Syahidah, A; Saad, C R; Hassan, M D; Rukayadi, Y; Norazian, M H; Kamarudin, M S

    2017-01-01

    The problems of bacterial diseases in aquaculture are primarily controlled by antibiotics. Medicinal plants and herbs which are seemed to be candidates of replacements for conventional antibiotics have therefore gained increasing interest. Current study was performed to investigate the presence of phytochemical constituents, antibacterial activities and composition of antibacterial active compounds in methanolic extract of local herb, Piper betle . Qualitative phytochemical analysis was firstly carried out to determine the possible active compounds in P. betle leaves methanolic extract. The antibacterial activities of major compounds from this extract against nine fish pathogenic bacteria were then assessed using TLC-bioautography agar overlay assay and their quantity were determined simultaneously by HPLC method. The use of methanol has proved to be successful in extracting numerous bioactive compounds including antibacterial compounds. The TLC-bioautography assay revealed the inhibitory action of two compounds which were identified as hydroxychavicol and eugenol. The $-caryophyllene however was totally inactive against all the tested bacterial species. In this study, the concentration of hydroxychavicol in extract was found to be 374.72±2.79 mg g-1, while eugenol was 49.67±0.16 mg g-1. Based on these findings, it could be concluded that hydroxychavicol and eugenol were the responsible compounds for the promising antibacterial activity of P. betle leaves methanolic extract. This inhibitory action has significantly correlated with the amount of the compounds in extract. Due to its potential, the extract of P. betle leaves or it compounds can be alternative source of potent natural antibacterial agents for aquaculture disease management.

  6. Texas Native Plants Yield Compounds with Cytotoxic Activities against Prostate Cancer Cells.

    Science.gov (United States)

    Shaffer, Corena V; Cai, Shengxin; Peng, Jiangnan; Robles, Andrew J; Hartley, Rachel M; Powell, Douglas R; Du, Lin; Cichewicz, Robert H; Mooberry, Susan L

    2016-03-25

    There remains a critical need for more effective therapies for the treatment of late-stage and metastatic prostate cancers. Three Texas native plants yielded three new and three known compounds with antiproliferative and cytotoxic activities against prostate cancer cells with IC50 values in the range of 1.7-35.0 μM. A new sesquiterpene named espadalide (1), isolated from Gochnatia hypoleuca, had low micromolar potency and was highly effective in clonogenic assays. Two known bioactive germacranolides (2 and 3) were additionally isolated from G. hypoleuca. Dalea frutescens yielded two new isoprenylated chalcones, named sanjuanolide (4) and sanjoseolide (5), and the known sesquiterpenediol verbesindiol (6) was isolated from Verbesina virginica. Mechanistic studies showed that 1-4 caused G2/M accumulation and the formation of abnormal mitotic spindles. Tubulin polymerization assays revealed that 4 increased the initial rate of tubulin polymerization, but did not change total tubulin polymer levels, and 1-3 had no effects on tubulin polymerization. Despite its cytotoxic activity, compound 6 did not initiate changes in cell cycle distribution and has a mechanism of action different from the other compounds. This study demonstrates that new compounds with significant biological activities germane to unmet oncological needs can be isolated from Texas native plants.

  7. Advanced Oxidation of Tartrazine and Brilliant Blue with Pulsed Ultraviolet Light Emitting Diodes

    OpenAIRE

    Scott, Robert; Mudimbi, Patrick; Miller, Michael E.; Magnuson, Matthew; Willison, Stuart; Phillips, Rebecca; Harper, Willie F.

    2017-01-01

    This study investigated the effect of ultraviolet light-emitting diodes (UVLEDs) coupled with hydrogen peroxide as an advanced oxidation process (AOP) for the degradation of two test chemicals. Brilliant Blue FCF consistently exhibited greater degradation than tartrazine, with 83% degradation after 300 minutes at the 100% duty cycle compared with only 17% degradation of tartrazine under the same conditions. These differences are attributable to the structural properties of the compounds. Duty...

  8. Analysis of Indonesian Spice Essential Oil Compounds That Inhibit Locomotor Activity in Mice

    Science.gov (United States)

    Muchtaridi; Diantini, Adjeng; Subarnas, Anas

    2011-01-01

    Some fragrance components of spices used for cooking are known to have an effect on human behavior. The aim of this investigation was to examine the effect of the essential oils of basil (Ocimum formacitratum L.) leaves, lemongrass (Cymbopogon citrates L.) herbs, ki lemo (Litsea cubeba L.) bark, and laja gowah (Alpinia malaccencis Roxb.) rhizomes on locomotor activity in mice and identify the active component(s) that might be responsible for the activity. The effect of the essential oils was studied by a wheel cage method and the active compounds of the essential oils were identified by GC/MS analysis. The essential oils were administered by inhalation at doses of 0.1, 0.3, and 0.5 mL/cage. The results showed that the four essential oils had inhibitory effects on locomotor activity in mice. Inhalation of the essential oils of basil leaves, lemongrass herbs, ki lemo bark, and laja gowah rhizomes showed the highest inhibitory activity at doses of 0.5 (57.64%), 0.1 (55.72%), 0.5 (60.75%), and 0.1 mL/cage (47.09%), respectively. The major volatile compounds 1,8-cineole, α-terpineol, 4-terpineol, citronelol, citronelal, and methyl cinnamate were identified in blood plasma of mice after inhalation of the four oils. These compounds had a significant inhibitory effect on locomotion after inhalation. The volatile compounds of essential oils identified in the blood plasma may correlate with the locomotor-inhibiting properties of the oil when administered by inhalation.

  9. Cytotoxicity, antimicrobial and antioxidant activity of eight compounds isolated from Entada abyssinica (Fabaceae).

    Science.gov (United States)

    Dzoyem, Jean P; Melong, Raduis; Tsamo, Armelle T; Tchinda, Alembert T; Kapche, Deccaux G W F; Ngadjui, Bonaventure T; McGaw, Lyndy J; Eloff, Jacobus N

    2017-03-06

    Entada abyssinica is a plant traditionally used against gastrointestinal bacterial infections. Eight compounds including three flavonoids, three terpenoids, a monoglyceride and a phenolic compound isolated from E. abyssinica were investigated for their cytotoxicity, antibacterial and antioxidant activity. Compounds 7 and 2 had remarkable activity against Salmonella typhimurium with the lowest respective minimum inhibitory concentration (MIC) values of 1.56 and 3.12 µg/mL. The antioxidant assay gave IC 50 values varied from 0.48 to 2.87 μg/mL in the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, from 2.53 to 17.04 μg/mL in the 2,2'-Azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS) assay and from 1.43 to 103.98 µg/mL in the FRAP assay. Compounds had relatively low cytotoxicity (LC 50 values ranging from 22.42 to 80.55 µg/mL) towards Vero cells. Ursolic acid had the most potent cytotoxicity against THP-1 and RAW 264.7 cells with LC 50 values of 9.62 and 4.56 μg/mL respectively, and selectivity index values of 7.32 and 15.44 respectively. Our findings suggest that among the terpenoid and flavonoid compounds studied, entadanin (compound 7) possess tremendous antibacterial activity against S. typhimurium and could be developed for the treatment of bacterial diseases.

  10. Inhibitory effect of Sphagnum palustre extract and its bioactive compounds on aromatase activity

    Directory of Open Access Journals (Sweden)

    Hee Jeong Eom

    2016-09-01

    Full Text Available Sphagnum palustre (a moss has been traditionally used in Korea for the cure of several diseases such as cardiac pain and stroke. In this research, the inhibitory effect of S. palustre on aromatase (cytochrome P450 19, CYP19 activity was studied. [1β-3H] androstenedione was used as a substrate and incubated with S. palustre extract and recombinant human CYP19 in the presence of NADPH. S. palustre extract inhibited aromatase in a concentration-dependent manner (IC50 value: 36.4 ± 8.1 µg/mL. To elucidate the major compounds responsible for the aromatase inhibitory effects of S. palustre extract, nine compounds were isolated from the extract and tested for their inhibition of aromatase activity. Compounds 1, 6, and 7 displayed aromatase inhibition, while the inhibition by the other compounds was negligible.

  11. White emission from nano-structured top-emitting organic light-emitting diodes based on a blue emitting layer

    International Nuclear Information System (INIS)

    Hyun, Woo Jin; Park, Jung Jin; Park, O Ok; Im, Sang Hyuk; Chin, Byung Doo

    2013-01-01

    We demonstrated that white emission can be obtained from nano-structured top-emitting organic light-emitting diodes (TEOLEDs) based on a blue emitting layer (EML). The nano-structured TEOLEDs were fabricated on nano-patterned substrates, in which both optical micro-cavity and scattering effects occur simultaneously. Due to the combination of these two effects, the electroluminescence spectra of the nano-structured device with a blue EML exhibited not only blue but also yellow colours, which corresponded to the intrinsic emission of the EML and the resonant emission of the micro-cavity effect. Consequently, it was possible to produce white emission from nano-structured TEOLEDs without employing a multimode micro-cavity. The intrinsic emission wavelength can be varied by altering the dopant used for the EML. Furthermore, the emissive characteristics turned out to be strongly dependent on the nano-pattern sizes of the nano-structured devices. (paper)

  12. Four new compounds isolated from Psoralea corylifolia and their diacylglycerol acyltransferase (DGAT) inhibitory activity.

    Science.gov (United States)

    Lin, Xin; Li, Ban-Ban; Zhang, Le; Li, Hao-Ze; Meng, Xiao; Jiang, Yi-Yu; Lee, Hyun-Sun; Cui, Long

    2018-05-14

    A new bakuchiol compound Δ 11 -12-hydroxy-12-dimethyl bakuchiol (1), a new flavanone compound 2(S)-6-methoxy-7- hydroxymethylene-4'-hydroxyl-flavanone (8), and two new isoflavanone compounds 4',7-dihydroxy-3'-(6"β-hydroxy-3″,7″-dimethyl-,2″,7″-dibutenyl)-geranylisoflavone (9) and 4',7-dihydroxy-3'-(7″-hydroxy-7″-methyl-2″,5″-dibutenyl)-geranylisoflavone (10) together with eight known compounds (2-7, 11, 12) were isolated from the P. corylifolia. Their structures were elucidated on the basis of spectroscopic and physico-chemical analyses. All the isolates were evaluated for in vitro inhibitory activity against DGAT1/2. Among them, compounds 3, 9 and 10 were found to exhibit selective inhibitory activity on DGAT1 with IC 50 values ranging from 93.7 ± 1.3 to 96.2 ± 1.1 μM. Compound 1 showed inhibition activity on DGAT1 with IC 50 values 73.4 ± 1.3 μM and inhibition of DGAT2 with IC 50 value 121.1 ± 1.3 μM. Copyright © 2018 Elsevier B.V. All rights reserved.

  13. Phenolic compounds from the leaf extract of artichoke (Cynara scolymus L.) and their antimicrobial activities.

    Science.gov (United States)

    Zhu, Xianfeng; Zhang, Hongxun; Lo, Raymond

    2004-12-01

    A preliminary antimicrobial disk assay of chloroform, ethyl acetate, and n-butanol extracts of artichoke (Cynara scolymus L.) leaf extracts showed that the n-butanol fraction exhibited the most significant antimicrobial activities against seven bacteria species, four yeasts, and four molds. Eight phenolic compounds were isolated from the n-butanol soluble fraction of artichoke leaf extracts. On the basis of high-performance liquid chromatography/electrospray ionization mass spectrometry, tandem mass spectrometry, and nuclear magnetic resonance techniques, the structures of the isolated compounds were determined as the four caffeoylquinic acid derivatives, chlorogenic acid (1), cynarin (2), 3,5-di-O-caffeoylquinic acid (3), and 4,5-di-O-caffeoylquinic acid (4), and the four flavonoids, luteolin-7-rutinoside (5), cynaroside (6), apigenin-7-rutinoside (7), and apigenin-7-O-beta-D-glucopyranoside (8), respectively. The isolated compounds were examined for their antimicrobial activities on the above microorganisms, indicating that all eight phenolic compounds showed activity against most of the tested organisms. Among them, chlorogenic acid, cynarin, luteolin-7-rutinoside, and cynaroside exhibited a relatively higher activity than other compounds; in addition, they were more effective against fungi than bacteria. The minimum inhibitory concentrations of these compounds were between 50 and 200 microg/mL.

  14. Recombination zone in white organic light emitting diodes with blue and orange emitting layers

    Science.gov (United States)

    Tsuboi, Taiju; Kishimoto, Tadashi; Wako, Kazuhiro; Matsuda, Kuniharu; Iguchi, Hirofumi

    2012-10-01

    White fluorescent OLED devices with a 10 nm thick blue-emitting layer and a 31 nm thick orange-emitting layer have been fabricated, where the blue-emitting layer is stacked on a hole transport layer. An interlayer was inserted between the two emitting layers. The thickness of the interlayer was changed among 0.3, 0.4, and 1.0 nm. White emission with CIE coordinates close to (0.33, 0.33) was observed from all the OLEDs. OLED with 0.3 nm thick interlayer gives the highest maximum luminous efficiency (11 cd/A), power efficiency (9 lm/W), and external quantum efficiency (5.02%). The external quantum efficiency becomes low with increasing the interlayer thickness from 0 nm to 1.0 nm. When the location of the blue- and orange-emitting layers is reversed, white emission was not obtained because of too weak blue emission. It is suggested that the electron-hole recombination zone decreases nearly exponentially with a distance from the hole transport layer.

  15. Benzoporphyrin derivative and light-emitting diode for use in photodynamic therapy: Applications of space light-emitting diode technology

    International Nuclear Information System (INIS)

    Whelan, Harry T.; Houle, John M.; Bajic, Dawn M.; Schmidt, Meic H.; Reichert, Kenneth W. II; Meyer, Glenn A.

    1998-01-01

    Photodynamic therapy (PDT) is a cancer treatment modality that recently has been applied as adjuvant therapy for brain tumors. PDT consists of intravenously injecting a photosensitizer, which preferentially accumulates in tumor cells, into a patient and then activating the photosensitizer with a light source. This results in free radical generation followed by cell death. The development of more effective light sources for PDT of brain tumors has been facilitated by applications of space light-emitting diode array technology; thus permitting deeper tumor penetration of light and use of better photosensitizers. Currently, the most commonly used photosensitizer for brain tumor PDT is Photofrin registered . Photofrin registered is a heterogeneous mixture of compounds derived from hematoporphyrin. Photofrin registered is activated with a 630 nm laser light and does destroy tumor cells in animal models and humans. However, treatment failure does occur using this method. Most investigators attribute this failure to the limited penetration of brain tissue by a 630 nm laser light and to the fact that Photofrin registered has only a minor absorption peak at 630 nm, meaning that only a small fraction of the chemical is activated. Benzoporphyrin Derivative Monoacid Ring A (BPD) is a new, second generation photosensitizer that can potentially improve PDT for brain tumors. BPD has a major absorption peak at 690 nm, which gives it two distinct advantages over Photofrin registered . First, longer wavelengths of light penetrate brain tissue more easily so that larger tumors could be treated, and second, the major absorption peak means that a larger fraction of the drug is activated upon exposure to light. In the first part of this project we have studied the tumoricidal effects of BPD in vitro using 2A9 canine glioma and U373 human glioblastoma cell cultures. Using light emitting diodes (LED) with a peak emission of 688 nm as a light source, cell kill of up to 86 percent was

  16. A novel red-emitting phosphor for white light-emitting diodes

    International Nuclear Information System (INIS)

    Ren, Fuqiang; Chen, Donghua

    2010-01-01

    A novel red-emitting phosphor of Eu 3+ -activated molybdate was prepared at 850 o C by a modified solid-state reaction. Photoluminescence (PL) results showed that the phosphor can be efficiently excited by UV-visible light from 350 to 550 nm, and exhibited bright red emission at 614 nm. XPS are taken to investigate the structure and compositions of this material. The crystallization and particle sizes of the phosphor have been investigated by using powder X-ray diffraction (XRD) and transmission electron microscopy (TEM). TEM images show that the grain size of the phosphor is about 30 nm which is in full agreement with the theoretical calculation data from the XRD patterns.

  17. Fabrication and characterization of GaN-based light-emitting diodes without pre-activation of p-type GaN.

    Science.gov (United States)

    Hu, Xiao-Long; Wang, Hong; Zhang, Xi-Chun

    2015-01-01

    We fabricated GaN-based light-emitting diodes (LEDs) without pre-activation of p-type GaN. During the fabrication process, a 100-nm-thick indium tin oxide film was served as the p-type contact layer and annealed at 500°C in N2 ambient for 20 min to increase its transparency as well as to activate the p-type GaN. The electrical measurements showed that the LEDs were featured by a lower forward voltage and higher wall-plug efficiency in comparison with LEDs using pre-activation of p-type GaN. We discussed the mechanism of activation of p-type GaN at 500°C in N2 ambient. Furthermore, x-ray photoemission spectroscopy examinations were carried out to study the improved electrical performances of the LEDs without pre-activation of p-type GaN.

  18. Natural compounds' activity against cancer stem-like or fast-cycling melanoma cells.

    Directory of Open Access Journals (Sweden)

    Malgorzata Sztiller-Sikorska

    Full Text Available BACKGROUND: Accumulating evidence supports the concept that melanoma is highly heterogeneous and sustained by a small subpopulation of melanoma stem-like cells. Those cells are considered as responsible for tumor resistance to therapies. Moreover, melanoma cells are characterized by their high phenotypic plasticity. Consequently, both melanoma stem-like cells and their more differentiated progeny must be eradicated to achieve durable cure. By reevaluating compounds in heterogeneous melanoma populations, it might be possible to select compounds with activity not only against fast-cycling cells but also against cancer stem-like cells. Natural compounds were the focus of the present study. METHODS: We analyzed 120 compounds from The Natural Products Set II to identify compounds active against melanoma populations grown in an anchorage-independent manner and enriched with cells exerting self-renewing capacity. Cell viability, cell cycle arrest, apoptosis, gene expression, clonogenic survival and label-retention were analyzed. FINDINGS: Several compounds efficiently eradicated cells with clonogenic capacity and nanaomycin A, streptonigrin and toyocamycin were effective at 0.1 µM. Other anti-clonogenic but not highly cytotoxic compounds such as bryostatin 1, siomycin A, illudin M, michellamine B and pentoxifylline markedly reduced the frequency of ABCB5 (ATP-binding cassette, sub-family B, member 5-positive cells. On the contrary, treatment with maytansine and colchicine selected for cells expressing this transporter. Maytansine, streptonigrin, toyocamycin and colchicine, even if highly cytotoxic, left a small subpopulation of slow-dividing cells unaffected. Compounds selected in the present study differentially altered the expression of melanocyte/melanoma specific microphthalmia-associated transcription factor (MITF and proto-oncogene c-MYC. CONCLUSION: Selected anti-clonogenic compounds might be further investigated as potential adjuvants

  19. Cytotoxic and Antimigratory Activities of Phenolic Compounds from Dendrobium brymerianum

    Directory of Open Access Journals (Sweden)

    Pornprom Klongkumnuankarn

    2015-01-01

    Full Text Available Chromatographic separation of a methanol extract prepared from the whole plant of Dendrobium brymerianum led to the isolation of eight phenolic compounds. Among the isolated compounds (1–8, moscatilin (1, gigantol (3, lusianthridin (4, and dendroflorin (6 showed appreciable cytotoxicity against human lung cancer cell lines with IC50 values of 196.7, 23.4, 65.0, and 125.8 μg/mL, respectively, and exhibited antimigratory property at nontoxic concentrations. This study is the first report on the biological activities of this plant.

  20. Emerging applications for vertical cavity surface emitting lasers

    International Nuclear Information System (INIS)

    Harris, J S; O'sullivan, T; Sarmiento, T; Lee, M M; Vo, S

    2011-01-01

    Vertical cavity surface emitting lasers (VCSELs) emitting at 850 nm have experienced explosive growth in the past decade because of their many attractive optical features and incredibly low-cost manufacturability. This review reviews the foundations for GaAs-based VCSEL technology as well as the materials and device challenges to extend the operating wavelength to both shorter and longer wavelengths. We discuss some of the applications that are enabled by the integration of VCSELs with both active and passive semiconductor elements for telecommunications, both in vivo and in vitro biosensing, high-density optical storage and imaging at wavelengths much less than the diffraction limit of light

  1. An in vitro comparative study of the antioxidant activity and SIRT1 modulation of natural compounds.

    Science.gov (United States)

    Fusi, Jonathan; Bianchi, Sara; Daniele, Simona; Pellegrini, Silvia; Martini, Claudia; Galetta, Fabio; Giovannini, Luca; Franzoni, Ferdinando

    2018-05-01

    Oxidative stress arises from an imbalance between the production of free radicals and antioxidant defences. Several studies have suggested that dietary antioxidants (such as polyphenols and berberine) may counteract oxidative stress through the involvement of the Sirtuin 1/Adenosine Monophosphate-Activated Protein Kinase (SIRT1/AMPK) pathway. The aim of this study was to evaluate the direct and specific antioxidant activity of some natural compounds, as well as their ability to modulate the expression of SIRT1 and the activation of AMPK. Quercetin, tyrosol, ferulic acid, catechin, berberine and curcumin were evaluated for their specific and direct antioxidant activity with TOSC assay. Their ability to modulate SIRT1 and AMPK was assessed by immunoblotting assay, while their cytotoxicity by CellTiter-Blue Cell Viability Assay. No statistically significant decrease (p > 0.05) in the number of viable cells was found upon challenging with the natural compounds. Quercetin exhibited the highest antioxidant activity against peroxyl radical and peroxinitrate derivates, while curcumin showed the best anti-hydroxyl activity with respect to the other compounds and, most importantly, respect to the reference antioxidants. Finally, all the tested compounds significantly increased the SIRT1 expression and the activation of AMPK. Our results clearly disclose the specific antioxidant activity of these natural compounds and their ability to increase SIRT1 expression and AMPK activation. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  2. Hybrid light emitting transistors (Presentation Recording)

    Science.gov (United States)

    Muhieddine, Khalid; Ullah, Mujeeb; Namdas, Ebinazar B.; Burn, Paul L.

    2015-10-01

    Organic light-emitting diodes (OLEDs) are well studied and established in current display applications. Light-emitting transistors (LETs) have been developed to further simplify the necessary circuitry for these applications, combining the switching capabilities of a transistor with the light emitting capabilities of an OLED. Such devices have been studied using mono- and bilayer geometries and a variety of polymers [1], small organic molecules [2] and single crystals [3] within the active layers. Current devices can often suffer from low carrier mobilities and most operate in p-type mode due to a lack of suitable n-type organic charge carrier materials. Hybrid light-emitting transistors (HLETs) are a logical step to improve device performance by harnessing the charge carrier capabilities of inorganic semiconductors [4]. We present state of the art, all solution processed hybrid light-emitting transistors using a non-planar contact geometry [1, 5]. We will discuss HLETs comprised of an inorganic electron transport layer prepared from a sol-gel of zinc tin oxide and several organic emissive materials. The mobility of the devices is found between 1-5 cm2/Vs and they had on/off ratios of ~105. Combined with optical brightness and efficiencies of the order of 103 cd/m2 and 10-3-10-1 %, respectively, these devices are moving towards the performance required for application in displays. [1] M. Ullah, K. Tandy, S. D. Yambem, M. Aljada, P. L. Burn, P. Meredith, E. B. Namdas., Adv. Mater. 2013, 25, 53, 6213 [2] R. Capelli, S. Toffanin, G. Generali, H. Usta, A. Facchetti, M. Muccini, Nature Materials 2010, 9, 496 [3] T. Takenobu, S. Z. Bisri, T. Takahashi, M. Yahiro, C. Adachi, Y. Iwasa, Phys. Rev. Lett. 2008, 100, 066601 [4] H. Nakanotani, M. Yahiro, C. Adachi, K. Yano, Appl. Phys. Lett. 2007, 90, 262104 [5] K. Muhieddine, M. Ullah, B. N. Pal, P. Burn E. B. Namdas, Adv. Mater. 2014, 26,37, 6410

  3. A semi-classical model for the description of angular distribution of light particles emitted in nuclear reactions

    International Nuclear Information System (INIS)

    Zhang Jingshang

    1990-04-01

    A semi-classical model of multi-step direct and compound nuclear reactions has been proposed to describe the angular distributions of light particles emitted in reaction processes induced by nucleons with energies of several tens of MeV. The exact closed solution for the time-dependent master equation of the exciton model is applied. Based on the Fermi gas model, the scattering kernel for two-nucleon collisions includes the influence of the Fermi motion and the Pauli exclusion principle, which give a significant improvement in the description of the rise of the backward distributions. The angle-energy correlation for the first few steps of the collision process (multi-step direct process) yields further improvements in the description of the angular distribution. The pick-up mechanism is employed to describe the composite particle emission. This reasonable physical picture reproduces the experimental data of the energy spectra of composite particles satisfactorily. The angular distribution of the emitted composite particles is determined by an angular factor in terms of the momentum conservation of the nucleons forming the composite cluster. The generalized master equation is employed for the multi-step compound process. Thus a classical approach has been established to calculate the double differential cross sections for all kinds of particles emitted in multi-step nuclear reaction processes. (author). 19 refs, 6 figs, 1 tab

  4. THE Fe II EMISSION IN ACTIVE GALACTIC NUCLEI: EXCITATION MECHANISMS AND LOCATION OF THE EMITTING REGION

    International Nuclear Information System (INIS)

    Marinello, M.; Rodríguez-Ardila, A.; Garcia-Rissmann, A.; Sigut, T. A. A.; Pradhan, A. K.

    2016-01-01

    We present a study of Fe ii emission in the near-infrared region (NIR) for 25 active galactic nuclei (AGNs) to obtain information about the excitation mechanisms that power it and the location where it is formed. We employ an NIR Fe ii template derived in the literature and find that it successfully reproduces the observed Fe ii spectrum. The Fe ii bump at 9200 Å detected in all objects studied confirms that Lyα fluorescence is always present in AGNs. The correlation found between the flux of the 9200 Å bump, the 1 μm lines, and the optical Fe ii implies that Lyα fluorescence plays an important role in Fe ii production. We determined that at least 18% of the optical Fe ii is due to this process, while collisional excitation dominates the production of the observed Fe ii. The line profiles of Fe ii λ10502, O i λ11287, Ca ii λ8664, and Paβ were compared to gather information about the most likely location where they are emitted. We found that Fe ii, O i and Ca ii have similar widths and are, on average, 30% narrower than Paβ. Assuming that the clouds emitting the lines are virialized, we show that the Fe ii is emitted in a region twice as far from the central source than Paβ. The distance, though, strongly varies: from 8.5 light-days for NGC 4051 to 198.2 light-days for Mrk 509. Our results reinforce the importance of the Fe ii in the NIR to constrain critical parameters that drive its physics and the underlying AGN kinematics, as well as more accurate models aimed at reproducing this complex emission

  5. THE Fe II EMISSION IN ACTIVE GALACTIC NUCLEI: EXCITATION MECHANISMS AND LOCATION OF THE EMITTING REGION

    Energy Technology Data Exchange (ETDEWEB)

    Marinello, M. [Universidade Federal de Itajubá, Rua Doutor Pereira Cabral 1303, 37500-903, Itajubá, MG (Brazil); Rodríguez-Ardila, A.; Garcia-Rissmann, A. [Laboratório Nacional de Astrofísica, Rua Estados Unidos 154, Itajubá, MG, 37504-364 (Brazil); Sigut, T. A. A. [The University of Western Ontario, London, ON N6A 3K7 (Canada); Pradhan, A. K., E-mail: murilo.marinello@gmail.com [McPherson Laboratory, The Ohio State University, 140 W. 18th Ave., Columbus, OH 43210-1173 (United States)

    2016-04-01

    We present a study of Fe ii emission in the near-infrared region (NIR) for 25 active galactic nuclei (AGNs) to obtain information about the excitation mechanisms that power it and the location where it is formed. We employ an NIR Fe ii template derived in the literature and find that it successfully reproduces the observed Fe ii spectrum. The Fe ii bump at 9200 Å detected in all objects studied confirms that Lyα fluorescence is always present in AGNs. The correlation found between the flux of the 9200 Å bump, the 1 μm lines, and the optical Fe ii implies that Lyα fluorescence plays an important role in Fe ii production. We determined that at least 18% of the optical Fe ii is due to this process, while collisional excitation dominates the production of the observed Fe ii. The line profiles of Fe ii λ10502, O i λ11287, Ca ii λ8664, and Paβ were compared to gather information about the most likely location where they are emitted. We found that Fe ii, O i and Ca ii have similar widths and are, on average, 30% narrower than Paβ. Assuming that the clouds emitting the lines are virialized, we show that the Fe ii is emitted in a region twice as far from the central source than Paβ. The distance, though, strongly varies: from 8.5 light-days for NGC 4051 to 198.2 light-days for Mrk 509. Our results reinforce the importance of the Fe ii in the NIR to constrain critical parameters that drive its physics and the underlying AGN kinematics, as well as more accurate models aimed at reproducing this complex emission.

  6. Synthesis and biological activity of sulfur compounds showing structural analogy with combretastatin A-4

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Edson dos A. dos; Prado, Paulo C.; Carvalho, Wanderley R. de; Lima, Ricardo V. de; Beatriz, Adilson; Lima, Denis P. de, E-mail: denis.lima@ufms.br [Universidade Federal de Mato Grosso do Sul (UFMS), Campo Grande, MS (Brazil). Departamento de Quimica; Hamel, Ernest [Screening Technologies Branch, Developmental Therapeutics Program, Division of Cancer Treatment and Diagnosis, National Cancer Institute at Frederick, National Institutes of Health, Frederick, MD (United States); Dyba, Marzena A. [Basic Science Program , SAIC-Frederick, Inc., Structural Biophysics Laboratory National Cancer Institute, Frederick, MD (United States); Albuquerque, Sergio [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Ciencias Farmaceuticas

    2013-09-01

    We extended our previous exploration of sulfur bridges as bioisosteric replacements for atoms forming the bridge between the aromatic rings of combretastatin A-4. Employing coupling reactions between 5-iodo-1,2,3-trimethoxybenzene and substituted thiols, followed by oxidation to sulfones with m-CPBA, different locations for attaching the sulfur atom to ring A through the synthesis of nine compounds were examined. Antitubulin activity was performed with electrophoretically homogenous bovine brain tubulin, and activity occurred with the 1,2,3-trimethoxy-4-[(4-methoxyphenyl)thio]benzene (12), while the other compounds were inactive. The compounds were also tested for leishmanicidal activity using promastigote forms of Leishmania braziliensis (MHOM/BR175/M2904),and the greatest activity was observed with 1,2,3-trimethoxy-4-(phenylthio)benzene (10) and 1,2,3-trimethoxy-4-[(4-methoxyphenyl) sulfinyl]benzene (15). (author)

  7. Analysis of Organic Anionic Surfactants in Fine and Coarse Fractions of Freshly Emitted Sea Spray Aerosol

    Energy Technology Data Exchange (ETDEWEB)

    Cochran, Richard E.; Laskina, Olga; Jayarathne, Thilina; Laskin, Alexander; Laskin, Julia; Lin, Peng; Sultana, Camile M.; Lee, Christopher; Moore, Kathryn A.; Cappa, Christopher; Bertram, Timothy; Prather, Kimberly; Grassian, Vicki H.; Stone, Elizabeth

    2016-02-01

    The inclusion of organic compounds in freshly emitted sea spray aerosol (SSA) has been shown to be size-dependent, with an increasing organic fraction in smaller particles. Defining the molecular composition of sea spray aerosol has proven challenging, due to the mix of continental and background particles even in remote marine environments. Here we have used electrospray ionization-high resolution mass spectrometry in negative ion mode to identify organic compounds in nascent sea spray collected throughout a 25-day mesocosm experiment. Over 280 organic compounds from ten major homologous series were identified. These compounds were operationally defined as molecules containing a hydrophobic alkyl chain with a hydrophilic head group making them surface active. The most abundant class of molecules detected were saturated (C8–C24) and unsaturated (C12–C22) fatty acids. Fatty acid derivatives (including saturated oxo-fatty acids (C5–C18) and saturated hydroxy-fatty acids (C5–C18) were also identified. Interestingly, anthropogenic influences on SSA from the seawater were observed in the form of sulfate (C2–C7, C12–C17) and sulfonate (C16–C22) species. During the mesocosm, the distributions of molecules within each homologous series were observed to respond to variations among the levels of phytoplankton and bacteria in the seawater, indicating an important role of biological processes in determining the composition of SSA.

  8. Quantitative Structure Activity Relationship of Cinnamaldehyde Compounds against Wood-Decaying Fungi

    Directory of Open Access Journals (Sweden)

    Dongmei Yang

    2016-11-01

    Full Text Available Cinnamaldehyde, of the genius Cinnamomum, is a major constituent of the bark of the cinnamon tree and possesses broad-spectrum antimicrobial activity. In this study, we used best multiple linear regression (BMLR to develop quantitative structure activity relationship (QSAR models for cinnamaldehyde derivatives against wood-decaying fungi Trametes versicolor and Gloeophyllun trabeum. Based on the two optimal QSAR models, we then designed and synthesized two novel cinnamaldehyde compounds. The QSAR models exhibited good correlation coefficients: R2Tv = 0.910 for Trametes versicolor and R2Gt = 0.926 for Gloeophyllun trabeum. Small errors between the experimental and calculated values of two designed compounds indicated that these two QSAR models have strong predictability and stability.

  9. Activation energies for iodine-exchange systems containing organic iodine compounds

    Energy Technology Data Exchange (ETDEWEB)

    Ikeda, N. (Takyo Univ. of Education (Japan). Faculty of Science) Takahashi, Yasuko

    1976-01-01

    In studies on the nonequilibrium isotopic exchange method for determining iodine in organic iodine compounds, activation energies have been measured to find systems having appropriate rate of exchange reactions. Activation energies are discussed by considering the effect of the structure of organic iodine compounds, the concentrations of reactants and solvent, etc. In homogeneous systems, activation energy is found to become larger in the order of CH/sub 3/Iactivation energy is less in 100% acetone than in 90% acetone solution. In heterogeneous systems, e.g. org. I(aq.)--I/sub 2/(CCL/sub 4/ or C/sub 2/H/sub 4/Cl/sub 2/), activation energy increases in the order of 3,5-diiodotyrosine<3-iodotyrosine<5-iodouracil. The catalytic effect of I/sub 2/ is large, and the iodine ratio between I/sub 2/ and organic iodine is a predominant factor in determining the rate of the exchange reaction.

  10. Analysis of Indonesian Spice Essential Oil Compounds That Inhibit Locomotor Activity in Mice

    Directory of Open Access Journals (Sweden)

    Anas Subarnas

    2011-04-01

    Full Text Available Some fragrance components of spices used for cooking are known to have an effect on human behavior. The aim of this investigation was to examine the effect of the essential oils of basil (Ocimum formacitratum L. leaves, lemongrass (Cymbopogon citrates L. herbs, ki lemo (Litsea cubeba L. bark, and laja gowah (Alpinia malaccencis Roxb. rhizomes on locomotor activity in mice and identify the active component(s that might be responsible for the activity. The effect of the essential oils was studied by a wheel cage method and the active compounds of the essential oils were identified by GC/MS analysis. The essential oils were administered by inhalation at doses of 0.1, 0.3, and 0.5 mL/cage. The results showed that the four essential oils had inhibitory effects on locomotor activity in mice. Inhalation of the essential oils of basil leaves, lemongrass herbs, ki lemo bark, and laja gowah rhizomes showed the highest inhibitory activity at doses of 0.5 (57.64%, 0.1 (55.72%, 0.5 (60.75%, and 0.1 mL/cage (47.09%, respectively. The major volatile compounds 1,8-cineole, α-terpineol, 4-terpineol, citronelol, citronelal, and methyl cinnamate were identified in blood plasma of mice after inhalation of the four oils. These compounds had a significant inhibitory effect on locomotion after inhalation. The volatile compounds of essential oils identified in the blood plasma may correlate with the locomotor-inhibiting properties of the oil when administered by inhalation.

  11. Isolation and Identification of Active Compounds from Papaya Plants and Activities as Antimicrobial

    Science.gov (United States)

    Prasetya, A. T.; Mursiti, S.; Maryan, S.; Jati, N. K.

    2018-04-01

    Extraction and isolation of papaya seeds and leaves (Carica papaya L) has been performed using n-hexane and ethanol solvents. Further isolation of the extract obtained using ethyl acetate and diethyl ether solvents. The result of the phytochemical test of papaya extract obtained by mixture of an active compound of flavonoids, alkaloids, tannins, steroids, and saponins. Ethyl acetate isolates containing only flavonoids and diethyl ether isolates contain only alkaloids. Extracts and isolates from papaya plants had gram-positive antibacterial activity greater than the gram-negative bacteria, but both did not have antifungal activity. Papaya extracts have greater antibacterial activity than flavonoid isolates and alkaloid isolates. Strong antibacterial inhibitory sequences are extracts of papaya plants, flavonoid isolates, and alkaloid isolates.

  12. Molecular Descriptors Family on Structure Activity Relationships 2. Insecticidal Activity of Neonicotinoid Compounds

    Directory of Open Access Journals (Sweden)

    Sorana BOLBOACĂ

    2005-01-01

    Full Text Available The neonicotinoids are the newest major class of insecticides modeled after the basic nicotine molecule having improved insecticide activity and generally low toxicity. The insecticidal activities of neonicotinoids were previous studied using 3D and standard partial least squares regression models. The paper describes the ability of the MDF SAR methodology in prediction of insecticidal activities of neonicotinoid compounds. The best MDF SAR bi-varied model was validated on training and test sets and its ability on prediction of insecticidal activity was compared with previous reported models. Even if the MDF SAR methodology is complex and time consuming the results worth the effort because they are statistical significant better then previous reported results.

  13. Efficient organic light emitting-diodes (OLEDs)

    CERN Document Server

    Chang, Yi-Lu

    2015-01-01

    Following two decades of intense research globally, the organic light-emitting diode (OLED) has steadily emerged as the ultimate display technology of choice for the coming decades. Portable active matrix OLED displays have already become prevalent, and even large-sized ultra-high definition 4K TVs are being mass-produced. More exotic applications such as wearable displays have been commercialized recently. With the burgeoning success in displays, researchers are actively bringing the technology forward into the exciting solid-state lighting market. This book presents the knowledge needed for

  14. Simple Method of Preparation and Characterization of New Antifungal Active Biginelli Type Heterocyclic Compounds

    Science.gov (United States)

    Velan, A. Senthilkumara; Joseph, J.; Raman, N.

    2008-01-01

    A simple, efficient and cost effective method is described for the synthesis of Biginelli type heterocyclic compounds of dihydropyrimidinones analogous. They were prepared from a reaction mixture consisting of substituted benzaldehydes, thiourea and ethylacetoacetate using ammonium dihydrogenphosphate as catalyst. The procedure for the preparation of the compounds is environmentally benign and safe which is advantageous in terms of experimentation, catalyst reusability, yields of the products, shorter reaction times and preclusion of toxic solvents. The four new synthesised compounds were tested for their antifungal activity. They have good antifungal activity comparing to the standard (Fluconazole). PMID:23997611

  15. Bayesian screening for active compounds in high-dimensional chemical spaces combining property descriptors and molecular fingerprints.

    Science.gov (United States)

    Vogt, Martin; Bajorath, Jürgen

    2008-01-01

    Bayesian classifiers are increasingly being used to distinguish active from inactive compounds and search large databases for novel active molecules. We introduce an approach to directly combine the contributions of property descriptors and molecular fingerprints in the search for active compounds that is based on a Bayesian framework. Conventionally, property descriptors and fingerprints are used as alternative features for virtual screening methods. Following the approach introduced here, probability distributions of descriptor values and fingerprint bit settings are calculated for active and database molecules and the divergence between the resulting combined distributions is determined as a measure of biological activity. In test calculations on a large number of compound activity classes, this methodology was found to consistently perform better than similarity searching using fingerprints and multiple reference compounds or Bayesian screening calculations using probability distributions calculated only from property descriptors. These findings demonstrate that there is considerable synergy between different types of property descriptors and fingerprints in recognizing diverse structure-activity relationships, at least in the context of Bayesian modeling.

  16. Removal of chlorinated organic compounds from gas phase using electron beam technology

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Y.; Bulka, S.; Zimek, A. [Institute of Nuclear Chemistry and Technology, Warsaw (Poland); Chmielewski, A. G. [Institute of Nuclear Chemistry and Technology, Warsaw (Poland); Faculty of Chemical and Process Engineering, Warsaw University of Technology, Warsaw (Poland)

    2011-07-01

    Selected chlorinated organic compounds (Cl-HC), which are emitted from coal fired power plants, waste incinerators, chemical industry etc., are very harmful to the environment and human’s health. Some of them are listed as carcinogenic compounds by USA EPA. Recent studies show that some chlorinated organic compounds are suspected to be precursors for dioxins formation. Chlorinated organic compounds decomposition in air in an electron beam (EB) generated plasma reactor technology was studied. We selected cis-dichloroethylene (cis-DCE), 1,4-dichlorobenznene(1,4-DCB), 1-chloronaphthalene as studied objects. It is found that chlorinated organic compounds can be decomposed in an electron beam generated plasma reactor. The order of decomposition efficiency of these compounds are: cis-DCE > 1,4-DCB> 1-chloronaphthalene. (author)

  17. Phenolic compounds from Glycyrrhiza pallidiflora Maxim. and their cytotoxic activity.

    Science.gov (United States)

    Shults, Elvira E; Shakirov, Makhmut M; Pokrovsky, Mikhail A; Petrova, Tatijana N; Pokrovsky, Andrey G; Gorovoy, Petr G

    2017-02-01

    Twenty-one phenolic compounds (1-21) including dihydrocinnamic acid, isoflavonoids, flavonoids, coumestans, pterocarpans, chalcones, isoflavan and isoflaven, were isolated from the roots of Glycyrrhiza pallidiflora Maxim. Phloretinic acid (1), chrysin (6), 9-methoxycoumestan (8), isoglycyrol (9), 6″-O-acetylanonin (19) and 6″-O-acetylwistin (21) were isolated from G. pallidiflora for the first time. Isoflavonoid acetylglycosides 19, 21 might be artefacts that could be produced during the EtOAc fractionation process of whole extract. Compounds 2-4, 10, 11, 19 and 21 were evaluated for their cytotoxic activity with respect to model cancer cell lines (CEM-13, MT-4, U-937) using the conventional MTT assays. Isoflavonoid calycosin (4) showed the best potency against human T-cell leukaemia cells MT-4 (CTD 50 , 2.9 μM). Pterocarpans medicarpin (10) and homopterocarpin (11) exhibit anticancer activity in micromolar range with selectivity on the human monocyte cells U-937. The isoflavan (3R)-vestitol (16) was highly selective on the lymphoblastoid leukaemia cells CEM-13 and was more active than the drug doxorubicin.

  18. High-efficiency tris(8-hydroxyquinoline)aluminum (Alq3) complexes for organic white-light-emitting diodes and solid-state lighting.

    Science.gov (United States)

    Pérez-Bolívar, César; Takizawa, Shin-ya; Nishimura, Go; Montes, Victor A; Anzenbacher, Pavel

    2011-08-08

    Combinations of electron-withdrawing and -donating substituents on the 8-hydroxyquinoline ligand of the tris(8-hydroxyquinoline)aluminum (Alq(3)) complexes allow for control of the HOMO and LUMO energies and the HOMO-LUMO gap responsible for emission from the complexes. Here, we present a systematic study on tuning the emission and electroluminescence (EL) from Alq(3) complexes from the green to blue region. In this study, we explored the combination of electron-donating substituents on C4 and C6. Compounds 1-6 displayed the emission tuning between 478 and 526 nm, and fluorescence quantum yield between 0.15 and 0.57. The compounds 2-6 were used as emitters and hosts in organic light-emitting diodes (OLEDs). The highest OLED external quantum efficiency (EQE) observed was 4.6%, which is among the highest observed for Alq(3) complexes. Also, the compounds 3-5 were used as hosts for red phosphorescent dopants to obtain white light-emitting diodes (WOLED). The WOLEDs displayed high efficiency (EQE up to 19%) and high white color purity (color rendering index (CRI≈85). Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Activation of Persulfates by Graphitized Nanodiamonds for Removal of Organic Compounds.

    Science.gov (United States)

    Lee, Hongshin; Kim, Hyoung-Il; Weon, Seunghyun; Choi, Wonyong; Hwang, Yu Sik; Seo, Jiwon; Lee, Changha; Kim, Jae-Hong

    2016-09-20

    This study introduces graphited nanodiamond (G-ND) as an environmentally friendly, easy-to-regenerate, and cost-effective alternative catalyst to activate persulfate (i.e., peroxymonosulfate (PMS) and peroxydisulfate (PDS)) and oxidize organic compounds in water. The G-ND was found to be superior for persulfate activation to other benchmark carbon materials such as graphite, graphene, fullerene, and carbon nanotubes. The G-ND/persulfate showed selective reactivity toward phenolic compounds and some pharmaceuticals, and the degradation kinetics were not inhibited by the presence of oxidant scavengers and natural organic matter. These results indicate that radical intermediates such as sulfate radical anion and hydroxyl radical are not majorly responsible for this persulfate-driven oxidation of organic compounds. The findings from linear sweep voltammetry, thermogravimetric analysis, Fourier transform infrared spectroscopy, and electron paramagnetic resonance spectroscopy analyses suggest that the both persulfate and phenol effectively bind to G-ND surface and are likely to form charge transfer complex, in which G-ND plays a critical role in mediating facile electron transfer from phenol to persulfate.

  20. Effects of extraction methods of phenolic compounds from Xanthium strumarium L. and their antioxidant activity

    Directory of Open Access Journals (Sweden)

    R. Scherer

    2014-03-01

    Full Text Available The effect of extraction methods and solvents on overall yield, total phenolic content, antioxidant activity, and the composition of the phenolic compounds in Xanthium strumarium extracts were studied. The antioxidant activity was determined by using 2,2-diphenyl-1-picrylhydrazyl radical (DPPH, and the composition of the phenolic compounds was determined by HPLC-DAD and LC/MS. All results were affected by the extraction method, especially by the solvent used, and the best results were obtained with the methanol extract. The methanolic and ethanolic extracts exhibited strong antioxidant activity, and the chlorogenic and ferulic acids were the most abundant phenolic compounds in the extracts.

  1. Anti-inflammatory activity of different agave plants and the compound cantalasaponin-1.

    Science.gov (United States)

    Monterrosas-Brisson, Nayeli; Ocampo, Martha L Arenas; Jiménez-Ferrer, Enrique; Jiménez-Aparicio, Antonio R; Zamilpa, Alejandro; Gonzalez-Cortazar, Manases; Tortoriello, Jaime; Herrera-Ruiz, Maribel

    2013-07-10

    Species of the agave genus, such as Agave tequilana, Agave angustifolia and Agave americana are used in Mexican traditional medicine to treat inflammation-associated conditions. These plants' leaves contain saponin compounds which show anti-inflammatory properties in different models. The goal of this investigation was to evaluate the anti-inflammatory capacity of these plants, identify which is the most active, and isolate the active compound by a bio-directed fractionation using the ear edema induced in mice with 12-O-tetradecanoylphorbol-13-acetate (TPA) technique. A dose of 6 mg/ear of acetone extract from the three agave species induced anti-inflammatory effects, however, the one from A. americana proved to be the most active. Different fractions of this species showed biological activity. Finally the F5 fraction at 2.0 mg/ear induced an inhibition of 85.6%. We identified one compound in this fraction as (25R)-5α-spirostan-3β,6α,23α-triol-3,6-di-O-β-D-glucopyranoside (cantalasaponin-1) through 1H- and 13C-NMR spectral analysis and two dimensional experiments like DEPT NMR, COSY, HSQC and HMBC. This steroidal glycoside showed a dose dependent effect of up to 90% of ear edema inhibition at the highest dose of 1.5 mg/ear.

  2. Sulfur-containing heterocyclic compounds with potential antidiabetic activity

    Directory of Open Access Journals (Sweden)

    E. A. Savateeva

    2014-12-01

    Full Text Available The essential link in the pathogenesis of diabetes mellitus and its complications is a non-enzymatic glycosylation of proteins. However, modern endocrinology lacks of clinically effective pharmaceuticals for its correction. The screening of 23 derivatives of 1,3,4-thiadiazine the ability to inhibit the reaction of non-enzymatic glycosylation of proteins in vitro was held, and 11 the most active compounds of them were selected, also the relationship «structure – activity» was investigated. An essential part of the pathogenesis of diabetes mellitus and its complications is non-enzymatic glycosylation of proteins. However, modern endocrinology lacks clinically effective medicines for its correction.

  3. Hybrid energy storage systems utilizing redox active organic compounds

    Science.gov (United States)

    Wang, Wei; Xu, Wu; Li, Liyu; Yang, Zhenguo

    2015-09-08

    Redox flow batteries (RFB) have attracted considerable interest due to their ability to store large amounts of power and energy. Non-aqueous energy storage systems that utilize at least some aspects of RFB systems are attractive because they can offer an expansion of the operating potential window, which can improve on the system energy and power densities. One example of such systems has a separator separating first and second electrodes. The first electrode includes a first current collector and volume containing a first active material. The second electrode includes a second current collector and volume containing a second active material. During operation, the first source provides a flow of first active material to the first volume. The first active material includes a redox active organic compound dissolved in a non-aqueous, liquid electrolyte and the second active material includes a redox active metal.

  4. 2 W high efficiency PbS mid-infrared surface emitting laser

    Science.gov (United States)

    Ishida, A.; Sugiyama, Y.; Isaji, Y.; Kodama, K.; Takano, Y.; Sakata, H.; Rahim, M.; Khiar, A.; Fill, M.; Felder, F.; Zogg, H.

    2011-09-01

    High efficiency laser operation with output power exceeding 2 W was obtained for vertical external-cavity PbS based IV-VI compound surface emitting quantum-well structures. The laser showed external quantum efficiency as high as 16%. Generally, mid-infrared III-V or II-VI semiconductor laser operation utilizing interband electron transitions are restricted by Auger recombination and free carrier absorption. Auger recombination is much lower in the IV-VI semiconductors, and the free-carrier absorption is significantly reduced by an optically pumped laser structure including multi-step optical excitation layers.

  5. Imaging instrument for positron emitting heavy ion beam injection

    International Nuclear Information System (INIS)

    Llacer, J.; Chatterjee, A.; Jackson, H.C.; Lin, J.C.; Zunzunegui, M.V.

    1978-10-01

    The design and performance of an instrument for the imaging of coincidence annihilation gamma rays emitted from the end point of the trajectories of radioactive high-energy heavy ions is described. The positron-emitting heavy ions are the result of nuclear fragmentation of accelerated heavy ions used in cancer therapy or diagnostic medicine. The instrument constructed is capable of locating the ion beam trajectory end point within 1 mm for an injected activity of 200 nanoCi in a measurement time of 1 sec in some favorable conditions. Limited imaging in three dimensions is also demonstrated

  6. Aldose Reductase Inhibitory Activity of Compounds from  Zea mays L.

    Science.gov (United States)

    Kim, Tae Hyeon; Kim, Jin Kyu; Kang, Young-Hee; Lee, Jae-Yong; Kang, Il Jun; Lim, Soon Sung

    2013-01-01

    Aldose reductase (AR) inhibitors have a considerable therapeutic potential against diabetes complications and do not increase the risk of hypoglycemia. Through bioassay-guided fractionation of an EtOH extract of the kernel from purple corn (Zea mays L.), 7 nonanthocyanin phenolic compounds (compound 1–7) and 5 anthocyanins (compound 8–12) were isolated. These compounds were investigated by rat lens aldose reductase (RLAR) inhibitory assays. Kinetic analyses of recombinant human aldose reductase (rhAR) were performed, and intracellular galactitol levels were measured. Hirsutrin, one of 12 isolated compounds, showed the most potent RLAR inhibitory activity (IC50, 4.78 μM). In the kinetic analyses using Lineweaver-Burk plots of 1/velocity and 1/substrate concentration, hirsutrin showed competitive inhibition against rhAR. Furthermore, hirsutrin inhibited galactitol formation in rat lens and erythrocytes sample incubated with a high concentration of galactose; this finding indicates that hirsutrin may effectively prevent osmotic stress in hyperglycemia. Therefore, hirsutrin derived from Zea mays L. may be a potential therapeutic agent against diabetes complications. PMID:23586057

  7. Screening SIRT1 Activators from Medicinal Plants as Bioactive Compounds against Oxidative Damage in Mitochondrial Function

    Directory of Open Access Journals (Sweden)

    Yi Wang

    2016-01-01

    Full Text Available Sirtuin type 1 (SIRT1 belongs to the family of NAD+ dependent histone deacetylases and plays a critical role in cellular metabolism and response to oxidative stress. Traditional Chinese medicines (TCMs, as an important part of natural products, have been reported to exert protective effect against oxidative stress in mitochondria. In this study, we screened SIRT1 activators from TCMs and investigated their activities against mitochondrial damage. 19 activators were found in total by in vitro SIRT1 activity assay. Among those active compounds, four compounds, ginsenoside Rb2, ginsenoside F1, ginsenoside Rc, and schisandrin A, were further studied to validate the SIRT1-activation effects by liquid chromatography-mass spectrometry and confirm their activities against oxidative damage in H9c2 cardiomyocytes exposed to tert-butyl hydroperoxide (t-BHP. The results showed that those compounds enhanced the deacetylated activity of SIRT1, increased ATP content, and inhibited intracellular ROS formation as well as regulating the activity of Mn-SOD. These SIRT1 activators also showed moderate protective effects on mitochondrial function in t-BHP cells by recovering oxygen consumption and increasing mitochondrial DNA content. Our results suggested that those compounds from TCMs attenuated oxidative stress-induced mitochondrial damage in cardiomyocytes through activation of SIRT1.

  8. High-luminosity blue and blue-green gallium nitride light-emitting diodes.

    Science.gov (United States)

    Morkoç, H; Mohammad, S N

    1995-01-06

    Compact and efficient sources of blue light for full color display applications and lighting eluded and tantalized researchers for many years. Semiconductor light sources are attractive owing to their reliability and amenability to mass manufacture. However, large band gaps are required to achieve blue color. A class of compound semiconductors formed by metal nitrides, GaN and its allied compounds AIGaN and InGaN, exhibits properties well suited for not only blue and blue-green emitters, but also for ultraviolet emitters and detectors. What thwarted engineers and scientists from fabricating useful devices from these materials in the past was the poor quality of material and lack of p-type doping. Both of these obstacles have recently been overcome to the point where highluminosity blue and blue-green light-emitting diodes are now available in the marketplace.

  9. Control of a White Organic Light Emitting Diode emission parameters using a single doped RGB active layer

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, D. [Departamento de Ciência dos Materiais e i3N – Instituto de Nanoestruturas, Nanomodelação e Nanofabricação, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Campus da Caparica, 2829-516 Caparica (Portugal); Pinto, A.; Califórnia, A.; Gomes, J. [CeNTI – Centro de Nanotecnologia, Materiais Técnicos, Funcionais e Inteligentes, Rua Fernando Mesquita 2785, 4760-034 Vila Nova de Famalicão (Portugal); Pereira, L., E-mail: luiz@ua.pt [Departmento de Física e i3N – Instituto de Nanoestruturas, Nanomodelação e Nanofabricação, Universidade de Aveiro, 3810-193 Aveiro (Portugal)

    2016-09-15

    Highlights: • A simple WOLED for Solid State Lighting is proposed with high color stability. • Energy transfer and electroluminescence dynamics of a single RGB layer for WOLEDs. • White shade modulation and stability over large emitting areas and applied voltages. - Abstract: Solid State Lighting technologies based on Organic Light Emitting Diodes, became an interesting focus due to their unique properties. The use of a unique RGB active layer for white emission, although simple in theory, shows difficulty to stabilize both CIE coordinates and color modulation. In this work, a WOLED using a simple RGB layer, was developed achieving a high color stability and shade modulation. The RGB matrix comprises a blue host material NPB, doped with two guests, a green (Coumarin 153) and a red (DCM1) in low concentrations. The RGB layer carrier dynamics allows for the white emission in low device complexity and high stability. This was also shown independent of the white shade, obtained through small changes in the red dopant resulting in devices ranging from warm to cool white i.e. an easy color tuning. A detailed analysis of the opto-electrical behavior is made.

  10. Control of a White Organic Light Emitting Diode emission parameters using a single doped RGB active layer

    International Nuclear Information System (INIS)

    Pereira, D.; Pinto, A.; Califórnia, A.; Gomes, J.; Pereira, L.

    2016-01-01

    Highlights: • A simple WOLED for Solid State Lighting is proposed with high color stability. • Energy transfer and electroluminescence dynamics of a single RGB layer for WOLEDs. • White shade modulation and stability over large emitting areas and applied voltages. - Abstract: Solid State Lighting technologies based on Organic Light Emitting Diodes, became an interesting focus due to their unique properties. The use of a unique RGB active layer for white emission, although simple in theory, shows difficulty to stabilize both CIE coordinates and color modulation. In this work, a WOLED using a simple RGB layer, was developed achieving a high color stability and shade modulation. The RGB matrix comprises a blue host material NPB, doped with two guests, a green (Coumarin 153) and a red (DCM1) in low concentrations. The RGB layer carrier dynamics allows for the white emission in low device complexity and high stability. This was also shown independent of the white shade, obtained through small changes in the red dopant resulting in devices ranging from warm to cool white i.e. an easy color tuning. A detailed analysis of the opto-electrical behavior is made.

  11. Total phenolic and phytosterol compounds and the radical scavenging activity of germinated Australian sweet lupin flour.

    Science.gov (United States)

    Rumiyati; Jayasena, Vijay; James, Anthony P

    2013-12-01

    In addition to their favourable nutritional profile, legumes also contain a range of bioactive compounds such as phenolic compounds and phytosterols which may protect against chronic diseases including cancer and cardiovascular disease. Germination of some legume seeds has been previously reported to increase the concentration of the bioactive compounds. In this study, the effect of germination of Australian Sweet Lupin (ASL) seeds for 9 days on the concentration of some bioactive compounds and the radical scavenging activity in the resulting flour was determined. The concentration of total phenolic compounds in methanolic extracts of germinated ASL flour was determined using Folin Ciocalteu reagent and phytosterols in oil extracts were analyzed by gas-liquid chromatography. The methanolic and oil extracts were also used to determine radical scavenging activity toward 2,2-diphenyl-1-picrylhydrazyl. In the methanolic extracts of germinated ASL flour, phenolic contents and the antioxidant activity were significantly increased following germination (700 and 1400 %, respectively). Analysis of the oil extracts of germinated ASL flour revealed that the concentration of phytosterols and the antioxidant activity were also increased significantly compared to ungerminated ASL flour (300 and 800 %, respectively). The relative proportion of phytosterols in germinated ASL flour was: β-sitosterol (60 %), stigmasterol (30 %) and campesterol (10 %). Germination increases the concentration of bioactive compounds and the radical scavenging activity in the germinated ASL flour.

  12. Emergence of White Organic Light-Emitting Diodes Based on Thermally Activated Delayed Fluorescence

    Directory of Open Access Journals (Sweden)

    Peng Xiao

    2018-02-01

    Full Text Available Recently, thermally activated delayed fluorescence (TADF organic light-emitting diodes (OLEDs have attracted both academic and industrial interest due to their extraordinary characteristics, such as high efficiency, low driving voltage, bright luminance, lower power consumption and potentially long lifetime. In this invited review, the fundamental concepts of TADF have been firstly introduced. Then, main approaches to realize WOLEDs based on TADF have been summarized. More specifically, the recent development of WOLEDs based on all TADF emitters, WOLEDs based on TADF and conventional fluorescence emitters, hybrid WOLEDs based on blue TADF and phosphorescence emitters and WOLEDs based on TADF exciplex host and phosphorescence dopants is highlighted. In particular, design strategies, device structures, working mechanisms and electroluminescent processes of the representative WOLEDs based on TADF are reviewed. Finally, challenges and opportunities for further enhancement of the performance of WOLEDs based on TADF are presented.

  13. A QSAR, Pharmacokinetic and Toxicological Study of New Artemisinin Compounds with Anticancer Activity

    Directory of Open Access Journals (Sweden)

    Josinete B. Vieira

    2014-07-01

    Full Text Available The Density Functional Theory (DFT method and the 6-31G** basis set were employed to calculate the molecular properties of artemisinin and 20 derivatives with different degrees of cytotoxicity against the human hepatocellular carcinoma HepG2 line. Principal component analysis (PCA and hierarchical cluster analysis (HCA were employed to select the most important descriptors related to anticancer activity. The significant molecular descriptors related to the compounds with anticancer activity were the ALOGPS_log, Mor29m, IC5 and GAP energy. The Pearson correlation between activity and most important descriptors were used for the regression partial least squares (PLS and principal component regression (PCR models built. The regression PLS and PCR were very close, with variation between PLS and PCR of R2 = ±0.0106, R2ajust = ±0.0125, s = ±0.0234, F(4,11 = ±12.7802, Q2 = ±0.0088, SEV = ±0.0132, PRESS = ±0.4808 and SPRESS = ±0.0057. These models were used to predict the anticancer activity of eight new artemisinin compounds (test set with unknown activity, and for these new compounds were predicted pharmacokinetic properties: human intestinal absorption (HIA, cellular permeability (PCaCO2, cell permeability Maden Darby Canine Kidney (PMDCK, skin permeability (PSkin, plasma protein binding (PPB and penetration of the blood-brain barrier (CBrain/Blood, and toxicological: mutagenicity and carcinogenicity. The test set showed for two new artemisinin compounds satisfactory results for anticancer activity and pharmacokinetic and toxicological properties. Consequently, further studies need be done to evaluate the different proposals as well as their actions, toxicity, and potential use for treatment of cancers.

  14. Extremely Randomized Machine Learning Methods for Compound Activity Prediction

    Directory of Open Access Journals (Sweden)

    Wojciech M. Czarnecki

    2015-11-01

    Full Text Available Speed, a relatively low requirement for computational resources and high effectiveness of the evaluation of the bioactivity of compounds have caused a rapid growth of interest in the application of machine learning methods to virtual screening tasks. However, due to the growth of the amount of data also in cheminformatics and related fields, the aim of research has shifted not only towards the development of algorithms of high predictive power but also towards the simplification of previously existing methods to obtain results more quickly. In the study, we tested two approaches belonging to the group of so-called ‘extremely randomized methods’—Extreme Entropy Machine and Extremely Randomized Trees—for their ability to properly identify compounds that have activity towards particular protein targets. These methods were compared with their ‘non-extreme’ competitors, i.e., Support Vector Machine and Random Forest. The extreme approaches were not only found out to improve the efficiency of the classification of bioactive compounds, but they were also proved to be less computationally complex, requiring fewer steps to perform an optimization procedure.

  15. Standardization of Tragopogon graminifolius DC. Extract Based on Phenolic Compounds and Antioxidant Activity

    Directory of Open Access Journals (Sweden)

    Mohammad Hosein Farzaei

    2014-01-01

    Full Text Available Tragopogon graminifolius DC. (TG, Compositae family, is traditionally used for the treatment of various diseases like gastrointestinal and hepatic disorders. The aim of the present study is to standardize extracts from TG used for preparation of different dosage forms in traditional Iranian medicine (TIM based on phenolic compounds. For this purpose, total phenolic content and some phenolic compounds were determined in ethanolic extracts from aerial part and root of TG by HPLC method. Furthermore, antioxidant activity was evaluated using DPPH-HPLC methods. Caffeic acid, gallic acid, ρ-coumaric acid, ferulic acid, and catechin were detected in root and aerial part of TG. ρ-Coumaric acid (6.357 ± 0.014 mg·g−1 was dominant phenolic compound in aerial part followed by ferulic acid (1.24 ± 0.018 mg·g−1. Also, ρ-coumaric acid (2.685 ± 0.031 mg·g−1 was highly abundant in root, followed by catechin (2.067 ± 0.021 mg·g−1. Antioxidant activity of root extract (460.45 ± 0.78 µg Vit.E.E·mL−1 was better than that of aerial part. Generally, phenolic compounds are one of the major constituents of TG and could be used as markers for standardization of dosage forms prepared from this plant. Also, TG demonstrated significant antioxidant activity using DPPH-HPLC method. Phenolic compounds of TG may be responsible for its marked antioxidant properties.

  16. Two new phenolic compounds and antitumor activities of asparinin A from Asparagus officinalis.

    Science.gov (United States)

    Li, Xue-Mei; Cai, Jin-Long; Wang, Le; Wang, Wen-Xiang; Ai, Hong-Lian; Mao, Zi-Chao

    2017-02-01

    Two new phenolic acid compounds, asparoffin C (1) and asparoffin D (2), together with four known compounds, asparenyol (3), gobicusin B (4), 1-methoxy-2-hydroxy-4-[5-(4-hydroxyphenoxy)-3-penten-1-ynyl] phenol (5), and asparinin A (6), have been isolated from the stems of Asparagus officinalis. The structures were established by extensive spectroscopic methods (MS and 1D and 2D NMR). Compound 6 has obvious antitumor activities both in vitro and in vivo.

  17. Anticancer activity of botanical compounds in ancient fermented beverages (review).

    Science.gov (United States)

    McGovern, P E; Christofidou-Solomidou, M; Wang, W; Dukes, F; Davidson, T; El-Deiry, W S

    2010-07-01

    Humans around the globe probably discovered natural remedies against disease and cancer by trial and error over the millennia. Biomolecular archaeological analyses of ancient organics, especially plants dissolved or decocted as fermented beverages, have begun to reveal the preliterate histories of traditional pharmacopeias, which often date back thousands of years earlier than ancient textual, ethnohistorical, and ethnological evidence. In this new approach to drug discovery, two case studies from ancient Egypt and China illustrate how ancient medicines can be reconstructed from chemical and archaeological data and their active compounds delimited for testing their anticancer and other medicinal effects. Specifically, isoscopoletin from Artemisia argyi, artemisinin from Artemisia annua, and the latter's more easily assimilated semi-synthetic derivative, artesunate, showed the greatest activity in vitro against lung and colon cancers. In vivo tests of these compounds previously unscreened against lung and pancreatic cancers are planned for the future.

  18. Study of the relationship between chemical structure and antimicrobial activity in a series of hydrazine-based coordination compounds.

    Science.gov (United States)

    Dobrova, B N; Dimoglo, A S; Chumakov, Y M

    2000-08-01

    The dependence of antimicrobial activity on the structure of compounds is studied in a series of compounds based on hydrazine coordinated with ions of Cu(II), Ni(II) and Pd(II). The study has been carried out by means of the original electron-topological method developed earlier. A molecular fragment has been found that is only characteristic of biologically active compounds. Its spatial and electron parameters have been used for the quantitative assessment of the activity in view. The results obtained can be used for the antimicrobial activity prediction in a series of compounds with similar structures.

  19. Antioxidative activity and emulsifying properties of cuttlefish skin gelatin modified by oxidised phenolic compounds

    NARCIS (Netherlands)

    Aewsiri, T.; Benjakul, S.; Visessanguan, W.; Eun, J.B.; Wierenga, P.A.; Gruppen, H.

    2009-01-01

    Antioxidative activity and emulsifying properties of cuttlefish skin gelatin modified by different oxidised phenolic compounds including caffeic acid, ferulic acid and tannic acid at different concentrations were investigated. Oxidised phenolic compounds were covalently attached to gelatin as

  20. Antimycobacterial and cytotoxicity activity of synthetic and natural compounds

    Directory of Open Access Journals (Sweden)

    Ana O. de Souza

    2007-01-01

    Full Text Available Antimycobacterial and cytotoxicity activity of synthetic and natural compounds. Secondary metabolites from Curvularia eragrostidis and Drechslera dematioidea, Clusia sp. floral resin, alkaloids from Pilocarpus alatus, salicylideneanilines, piperidine amides, the amine 1-cinnamylpiperazine and chiral pyridinium salts were assayed on Mycobacterium tuberculosis H37Rv. N-(salicylidene-2-hydroxyaniline was the most effective compound with a minimal inhibitory concentration (MIC of 8 µmol/L. Dihydrocurvularin was moderately effective with a MIC of 40 µmol/L. Clusia sp. floral resin and a gallocatechin-epigallocatechin mixture showed MIC of 0.02 g/L and 38 µmol/L, respectively. The cytotoxicity was evaluated for N-(salicylidene-2-hydroxyaniline, curvularin, dihydrocurvularin and Clusia sp. floral resin, and the selectivity indexes were > 125, 0.47, 0.75 and 5, respectively.

  1. Radiation emitting devices act

    International Nuclear Information System (INIS)

    1970-01-01

    This Act, entitled the Radiation Emitting Devices Act, is concerned with the sale and importation of radiation emitting devices. Laws relating to the sale, lease or import, labelling, advertising, packaging, safety standards and inspection of these devices are listed as well as penalties for any person who is convicted of breaking these laws

  2. Activated Carbon Adsorption Characteristics of Multi-component Volatile Organic compounds in a Fixed Bed Adsorption Bed

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Jong Hoon; Rhee, Young Woo [Chungnam National University, Daejeon (Korea, Republic of); Lee, Sihyun [Korea Institute of Energy Research, Daejeon (Korea, Republic of)

    2016-04-15

    This study aims to examine absorption characteristics of toluene, isopropyl alcohol (IPA), ethyl acetate (EA), and ternary-compounds, all of which are widely used in industrial processes, by means of four types of commercial activated carbon substances. It turned out that among the three types of volatile organic compounds, the breakthrough point of activated carbon and that of IPA, whose affinity was the lowest, were the lowest, and then that of EA and that of toluene in the order. With the breakthrough point of IPA, which was the shortest, as the standard, changes in the breakthrough points of unary-compounds, binary-compounds, and ternary-compounds were examined. As a result, it turned out that the larger the number of elements, the lower the breakthrough point. This resulted from competitive adsorption, that is, substitution of substances with a low level of affinity with those with a high level of affinity. Hence, the adsorption of toluene-IPA-EA and ternary-compounds require a design of the activated carbon bed based on the breakthrough of IPA, and in the design of activated carbon beds in actual industries as well, a substance whose level of affinity is the lowest needs to be the standard.

  3. Screening of pharmacologically active small molecule compounds identifies antifungal agents against Candida biofilms

    Directory of Open Access Journals (Sweden)

    Takao eWatamoto

    2015-12-01

    Full Text Available Candida species have emerged as important and common opportunistic human pathogens, particularly in immunocompromised individuals. The current antifungal therapies either have toxic side effects or are insufficiently effect. The aim of this study is develop new small-molecule antifungal compounds by library screening methods using C. albicans, and to evaluate their antifungal effects on Candida biofilms and cytotoxic effects on human cells. Wild-type C. albicans strain SC5314 was used in library screening. To identify antifungal compounds, we screened a small-molecule library of 1,280 pharmacologically active compounds (LOPAC1280TM using an antifungal susceptibility test (AST. To investigate the antifungal effects of the hit compounds, ASTs were conducted using Candida strains in various growth modes, including biofilms. We tested the cytotoxicity of the hit compounds using human gingival fibroblast (hGF cells to evaluate their clinical safety. Only 35 compounds were identified by screening, which inhibited the metabolic activity of C. albicans by >50%. Of these, 26 compounds had fungistatic effects and 9 compounds had fungicidal effects on C. albicans. Five compounds, BAY11-7082, BAY11-7085, sanguinarine chloride hydrate, ellipticine and CV-3988, had strong fungicidal effects and could inhibit the metabolic activity of Candida biofilms. However, BAY11-7082, BAY11-7085, sanguinarine chloride hydrate and ellipticine were cytotoxic to hGF cells at low concentrations. CV-3988 showed no cytotoxicity at a fungicidal concentration.Four of the compounds identified, BAY11-7082, BAY11-7085, sanguinarine chloride hydrate and ellipticine, had toxic effects on Candida strains and hGF cells. In contrast, CV-3988 had fungicidal effects on Candida strains, but low cytotoxic effects on hGF cells. Therefore, this screening reveals agent, CV-3988 that was previously unknown to be antifungal agent, which could be a novel therapies for superficial mucosal

  4. Hammerhead ribozyme activity and oligonucleotide duplex stability in mixed solutions of water and organic compounds

    Directory of Open Access Journals (Sweden)

    Shu-ichi Nakano

    2014-01-01

    Full Text Available Nucleic acids are useful for biomedical targeting and sensing applications in which the molecular environment is different from that of a dilute aqueous solution. In this study, the influence of various types of mixed solutions of water and water-soluble organic compounds on RNA was investigated by measuring the catalytic activity of the hammerhead ribozyme and the thermodynamic stability of an oligonucleotide duplex. The compounds with a net neutral charge, such as poly(ethylene glycol, small primary alcohols, amide compounds, and aprotic solvent molecules, added at high concentrations changed the ribozyme-catalyzed RNA cleavage rate, with the magnitude of the effect dependent on the NaCl concentration. These compounds also changed the thermodynamic stability of RNA base pairs of an oligonucleotide duplex and its dependence on the NaCl concentration. Specific interactions with RNA molecules and reduced water activity could account for the inhibiting effects on the ribozyme catalysis and destabilizing effects on the duplex stability. The salt concentration dependence data correlated with the dielectric constant, but not with water activity, viscosity, and the size of organic compounds. This observation suggests the significance of the dielectric constant effects on the RNA reactions under molecular crowding conditions created by organic compounds.

  5. Highly Efficient White Organic Light Emitting Diodes Using New Blue Fluorescence Emitter.

    Science.gov (United States)

    Kim, Seungho; Kim, Beomjin; Lee, Jaehyun; Yu, Young-Jun; Park, Jongwook

    2015-07-01

    Two different emitting compounds, 1-[1,1';3',1"]Terphenyl-5'-yl-6-(10-[1,1';3',1"]terpheny-5'-yl- anthracen-9-yl)-pyrene (TP-AP-TP) and Poly-phenylene vinylene derivative (PDY 132) were used to white OLED device. By incorporating adjacent blue and yellow emitting layers in a multi-layered structure, highly efficient white emission has been attained. The device was fabricated with a hybrid configuration structure: ITO/PEDOT (40 nm)/PDY-132 (8-50 nm)/ NPB (10 nm)/TP-AP-TP (30 nm)/Alq3 (20 nm)/LiF (1 nm)/Al (200 nm). After fixing TP-AP-TP thickness of 30 nm by evaporation, PDY-132 thickness varied with 8, 15, 35, and 50 nm by spin coating in device. The luminance efficiency of the white devices at 10 mA/cm2 were 2.93 cd/A-6.55 cd/A. One of white devices showed 6.55 cd/A and white color of (0.290, 0.331).

  6. The scent of colorectal cancer: detection by volatile organic compound analysis

    NARCIS (Netherlands)

    de Boer, Nanne K. H.; de Meij, Tim G. J.; Oort, Frank A.; Ben Larbi, Ilhame; Mulder, Chris J. J.; van Bodegraven, Adriaan A.; van der Schee, Marc P.

    2014-01-01

    The overall metabolic state of an individual is reflected by emitted volatile organic compounds (VOCs), which are gaseous carbon-based chemicals. In this review, we will describe the potential of VOCs as fully noninvasive markers for the detection of neoplastic lesions of the colon. VOCs are

  7. Synthesis, pharmacological activity evaluation and molecular modeling of new polynuclear heterocyclic compounds containing benzimidazole derivatives.

    Science.gov (United States)

    Bassyouni, Fatma A; Saleh, Tamer S; ElHefnawi, Mahmoud M; Abd El-Moez, Sherein I; El-Senousy, Waled M; Abdel-Rehim, Mohamed E

    2012-12-01

    Novel heterocyclic compounds containing benzimidazole derivatives were synthesized from 2-(1H-benzimidazol-2-yl) acetonitrile (1) and arylhydrazononitrile derivative 2 was obtained via coupling of 1 with 4-methyl phenyldiazonium salt, which was then reacted with hydroxylamine hydrochloride to give amidooxime derivative 3. This product was cyclized into the corresponding oxadiazole derivative 4 upon reflux in acetic anhydride. Compound 4 was refluxed in DMF in the presence of triethylamine to give the corresponding 5-(1H-benzimidazol-2-yl)-2-p-tolyl-2H-1,2,3-triazol-4-amine 6. Treatment of compound 6 with ethyl chloroformate afforded 2,6-dihydro-2-(4-methylphenyl)-1,2,3-triazolo[4",5"-4',5']pyrimido[1,6-a]benzimidazole-5(4H)-one (8). 1,2-bis(2-cyanomethyl-1H-benzimidazol-1-yl)ethane-1,2-dione (10) was synthesized via the condensation reaction of 2-(1H-benzimidazol-2-yl) acetonitrile (1) and diethyloxalate. The reactivity of compound 10 towards some diamine reagents was studied. The in vitro antimicrobial activity of the synthesized compounds was investigated against several pathogenic bacterial strains such as Escherichia coli O157, Salmonella typhimurium, E. coli O119, S. paratyphi, Pseudomonas aeruginosa, Staphylococcus aureus, Listeria monocytogenes and Bacillus cereus. The results of MIC revealed that compounds 12a-c showed the most effective antimicrobial activity against tested strains. On the other hand, compounds 12a, b exhibited high activity against rotavirus Wa strain while compounds 12b, c exhibited high activity against adenovirus type 7. In silico target prediction, docking and validation of the compounds 12a-c were performed. The dialkylglycine decarboxylase bacterial enzyme was predicted as a potential bacterial target receptor using pharmacophore-based correspondence with previous leads; giving the highest normalized scores and a high correlation docking score with mean inhibition concentrations. A novel binding mechanism was predicted after docking

  8. Quinoline-Based Hybrid Compounds with Antimalarial Activity

    Directory of Open Access Journals (Sweden)

    Xhamla Nqoro

    2017-12-01

    Full Text Available The application of quinoline-based compounds for the treatment of malaria infections is hampered by drug resistance. Drug resistance has led to the combination of quinolines with other classes of antimalarials resulting in enhanced therapeutic outcomes. However, the combination of antimalarials is limited by drug-drug interactions. In order to overcome the aforementioned factors, several researchers have reported hybrid compounds prepared by reacting quinoline-based compounds with other compounds via selected functionalities. This review will focus on the currently reported quinoline-based hybrid compounds and their preclinical studies.

  9. Emission and profile characteristic of volatile organic compounds emitted from coke production, iron smelt, heating station and power plant in Liaoning Province, China.

    Science.gov (United States)

    Shi, Jianwu; Deng, Hao; Bai, Zhipeng; Kong, Shaofei; Wang, Xiuyan; Hao, Jiming; Han, Xinyu; Ning, Ping

    2015-05-15

    107 kinds of C₂-C₁₂ volatile organic compound (VOC) mass concentrations and profiles for four types of coal-fired stationary sources in Liaoning Province were studied by a dilution sampling system and GC-MS analysis method, which are of significant importance with regard to VOC emissions in northeast of China. The results showed that there were some differences among these VOC source profiles. The total mass concentrations of analyzed 107 VOC species varied from 10,917 to 19,652 μg m(-3). Halogenated hydrocarbons exhibited higher mass percentages for the VOC source profiles of iron smelt (48.8%) and coke production plant (37.7%). Aromatic hydrocarbons were the most abundant in heating station plant (69.1%). Ketones, alcohols and acetates held 45.0% of total VOCs in thermal power plant. For non-methane hydrocarbons (NMHCs), which are demanded for photochemical assessment in the USA, toluene and n-hexane were the most abundant species in the iron smelt, coke production and thermal power plant, with the mass percentages of 64.8%, 52.7% and 38.6%, respectively. Trimethylbenzene, n-propylbenzene and o,m-ethyltoluene approximately accounted for 70.0% in heating station plant. NMHCs emitted from coke production, iron smelt, heating station and power plant listed above presented different chemical reactivities. The average OH loss rate of NMHCs from heating station, was 4 to 5.6 times higher than that of NMHCs from iron smelt, coke production and power plant, which implies that VOCs emitted from heating station in northeast of China should be controlled firstly to avoid photochemical ozone pollution and protect human health. There are significant variations in the ratios of benzene/toluene and m, p-xylene/ethylbenzene of these coal-fired source profiles. The representativeness of the coal-fired sources studied and the VOC samples collected should be more closely examined. The accuracy of VOC source profiles related to coal-fired processes is highly dependent on

  10. Uptake and transport of positron-emitting tracer (18F) in plants

    International Nuclear Information System (INIS)

    Kume, Tamikazu; Matsuhashi, Shinpei; Shimazu, Masamitsu

    1997-01-01

    The transport of a positron-emitting isotope introduced into a plant was dynamically followed by a special observation apparatus called Positron-Emitting Tracer Imaging System' to observe the damage and recovery functions of plants in vivo. In the system, annihilation γ-rays from the positron emitter are detected with two planar detectors (5 x 6 cm 2 ). The water containing ca. 5 MBq/ml of 18 F was fed to the cut stem of soybean for 2 min and then the images of tracer activity were recorded for 30-50 min. When the midrib of a leaf near the petiole was cut just before measurement, the activity in the injured leaf was decreased but detected even at the apex. This result suggests that the damaged leaf recovered the uptake of water through the lamina. Maximum tracer activities in leaves of unirradiated plant were observed within 10 min, whereas those of irradiated plant at 100 Gy were observed after over 25 min. The final activity of irradiated plant after 30 min was lower than that of unirradiated plant. In case of beans, there was a difference in the absorption behavior of the 18 F-labeled water between unirradiated and irradiated samples. These results show that the system is effective to observe the uptake and transportation of water containing positron emitting tracer for the study of damage and recovery functions of plants. (Author)

  11. Compounds from Cynomorium songaricum with Estrogenic and Androgenic Activities Suppress the Oestrogen/Androgen-Induced BPH Process.

    Science.gov (United States)

    Wang, Xueni; Tao, Rui; Yang, Jing; Miao, Lin; Wang, Yu; Munyangaju, Jose Edouard; Wichai, Nuttapong; Wang, Hong; Zhu, Yan; Liu, Erwei; Chang, Yanxu; Gao, Xiumei

    2017-01-01

    To investigate the phytoestrogenic and phytoandrogenic activities of compounds isolated from CS and uncover the role of CS in prevention of oestrogen/androgen-induced BPH. Cells were treated with CS compounds, and immunofluorescence assay was performed to detect the nuclear translocation of ER α or AR in MCF-7 or LNCaP cells; luciferase reporter assay was performed to detect ERs or AR transcriptional activity in HeLa or AD293 cells; MTT assay was performed to detect the cell proliferation of MCF-7 or LNCaP cells. Oestrogen/androgen-induced BPH model was established in rat and the anti-BPH, anti-estrogenic, and anti-androgenic activities of CS in vivo were further investigated. The nuclear translocation of ER α was stimulated by nine CS compounds, three of which also stimulated AR translocation. The transcriptional activities of ER α and ER β were induced by five compounds, within which only ECG induced AR transcriptional activity as well. Besides, ECG stimulated the proliferation of both MCF-7 cells and LNCaP cells. CS extract suppressed oestrogen/androgen-induced BPH progress in vivo by downregulation of E2 and T level in serum and alteration of the expressions of ER α , ER β , and AR in the prostate. Our data demonstrates that compounds from CS exhibit phytoestrogenic and phytoandrogenic activities, which may contribute to inhibiting the oestrogen/androgen-induced BPH development.

  12. Inhibitory mechanism of chroman compound on LPS-induced nitric oxide production and nuclear factor-κB activation

    International Nuclear Information System (INIS)

    Kim, Byung Hak; Reddy, Alavala Matta; Lee, Kum-Ho; Chung, Eun Yong; Cho, Sung Min; Lee, Heesoon; Min, Kyung Rak; Kim, Youngsoo

    2004-01-01

    6-Hydroxy-7-methoxychroman-2-carboxylic acid phenylamide (KL-1156) is a novel chemically synthetic compound. In the present study, the chroman KL-1156 compound was found to inhibit lipopolysaccharide (LPS)-induced nitric oxide production in macrophages RAW 264.7. KL-1156 compound attenuated LPS-induced synthesis of both mRNA and protein of inducible nitric oxide synthase (iNOS), in parallel, and inhibited LPS-induced iNOS promoter activity, indicating that the chroman compound down-regulated iNOS expression at transcription level. As a mechanism of the anti-inflammatory action shown by KL-1156 compound, suppression of nuclear factor (NF)-κB has been documented. KL-1156 compound exhibited a dose-dependent inhibitory effect on LPS-induced NF-κB transcriptional activity in macrophages RAW 264.7. Furthermore, the compound inhibited LPS-induced nuclear translocation of NF-κB p65 and DNA binding activity of NF-κB complex, in parallel, but did not affect IκBα degradation. Taken together, this study demonstrated that chroman KL-1156 compound interfered with nuclear translocation step of NF-κB p65, which was attributable to its anti-inflammatory action

  13. Novel Br-DPQ blue light-emitting phosphors for OLED.

    Science.gov (United States)

    Dahule, H K; Thejokalyani, N; Dhoble, S J

    2015-06-01

    A new series of blue light-emitting 2,4-diphenylquinoline (DPQ) substituted blue light-emitting organic phosphors namely, 2-(4-methoxy-phenyl)-4-phenyl-quinoline (OMe-DPQ), 2-(4-methyl-phenyl)-4-phenylquinoline (M-DPQ), and 2-(4-bromo-phenyl)-4-phenylquinoline (Br-DPQ) were synthesized by substituting methoxy, methyl and bromine at the 2-para position of DPQ, respectively by Friedländer condensation of 2-aminobenzophenone and corresponding acetophenone. The synthesized phosphors were characterized by different techniques, e.g., Fourier transform infra-red (FTIR), differential scanning calorimeter (DSC), UV-visible absorption and photoluminescence spectra. FTIR spectra confirms the presence of chemical groups such as C=O, NH, or OH in all the three synthesized chromophores. DSC studies show that these complexes have good thermal stability. Although they are low-molecular-weight organic compounds, they have the potential to improve the stability and operating lifetime of a device made out of these complexes. The synthesized polymeric compounds demonstrate a bright emission in the blue region in the wavelength range of 405-450 nm in solid state. Thus the attachment of methyl, methoxy and bromine substituents to the diphenyl quinoline ring in these phosphors results in colour tuning of the phosphorescence. An electroluminescence (EL) cell of Br-DPQ phosphor was made and its EL behaviour was studied. A brightness-voltage characteristics curve of Br-DPQ cell revealed that EL begins at 400 V and then the brightness increases exponentially with applied AC voltage, while current-voltage (I-V) characteristics revealed that the turn on voltage of the fabricated EL cell was 11 V. Hence this phosphor can be used as a promising blue light material for electroluminescent devices. Copyright © 2014 John Wiley & Sons, Ltd.

  14. p53-independent structure-activity relationships of 3-ring mesogenic compounds' activity as cytotoxic effects against human non-small cell lung cancer lines.

    Science.gov (United States)

    Fukushi, Saori; Yoshino, Hironori; Yoshizawa, Atsushi; Kashiwakura, Ikuo

    2016-07-25

    We recently demonstrated the cytotoxicity of liquid crystal precursors (hereafter referred to as "mesogenic compounds") in the human non-small cell lung cancer (NSCLC) cell line A549 which carry wild-type p53. p53 mutations are observed in 50 % of NSCLC and contribute to their resistance to chemotherapy. To develop more effective and cancer-specific agents, in this study, we investigated the structure-activity relationships of mesogenic compounds with cytotoxic effects against multiple NSCLC cells. The pharmacological effects of mesogenic compounds were examined in human NSCLC cells (A549, LU99, EBC-1, and H1299) and normal WI-38 human fibroblast. Analyses of the cell cycle, cell-death induction, and capsases expression were performed. The 3-ring compounds possessing terminal alkyl and hydroxyl groups (compounds C1-C5) showed cytotoxicity in NSCLC cells regardless of the p53 status. The compounds C1 and C3, which possess a pyrimidine at the center of the core, induced G2/M arrest, while the compounds without a pyrimidine (C2, C4, and C5) caused G1 arrest; all compounds produced caspase-mediated cell death. These events occurred in a p53-independent manner. Furthermore, it was suggested that compounds induced cell death through p53-independent DNA damage-signaling pathway. Compounds C2, C4, and C5 did not show strong cytotoxicity in WI-38 cells, whereas C1 and C3 did. However, the cytotoxicity of compound C1 against WI-38 cells was improved by modulating the terminal alkyl chain lengths of the compound. We showed the p53-indepdent structure-activity relationships of mesogenic compounds related to the cytotoxic effects. These structure-activity relationships will be helpful in the development of more effective and cancer-specific agents.

  15. Chiral halogenated Schiff base compounds: green synthesis, anticancer activity and DNA-binding study

    Science.gov (United States)

    Ariyaeifar, Mahnaz; Amiri Rudbari, Hadi; Sahihi, Mehdi; Kazemi, Zahra; Kajani, Abolghasem Abbasi; Zali-Boeini, Hassan; Kordestani, Nazanin; Bruno, Giuseppe; Gharaghani, Sajjad

    2018-06-01

    Eight enantiomerically pure halogenated Schiff base compounds were synthesized by reaction of halogenated salicylaldehydes with 3-Amino-1,2-propanediol (R or S) in water as green solvent at ambient temperature. All compounds were characterized by elemental analyses, NMR (1H and 13C), circular dichroism (CD) and FT-IR spectroscopy. FS-DNA binding studies of these compounds carried out by fluorescence quenching and UV-vis spectroscopy. The obtained results revealed that the ligands bind to DNA as: (Rsbnd ClBr) > (Rsbnd Cl2) > (Rsbnd Br2) > (Rsbnd I2) and (Ssbnd ClBr) > (Ssbnd Cl2) > (Ssbnd Br2) > (Ssbnd I2), indicating the effect of halogen on binding constant. In addition, DNA-binding constant of the Ssbnd and R-enantiomers are different from each other. The ligands can form halogen bonds with DNA that were confirmed by molecular docking. This method was also measured the bond distances and bond angles. The study of obtained data can have concluded that binding affinity of the ligands to DNA depends on strength of halogen bonds. The potential anticancer activity of ligands were also evaluated on MCF-7 and HeLa cancer cell lines by using MTT assay. The results showed that the anticancer activity and FS-DNA interaction is significantly dependent on the stereoisomers of Schiff base compounds as R-enantiomers displayed significantly higher activity than S-enantiomers. The molecular docking was also used to illustrate the specific DNA-binding of synthesized compounds and groove binding mode of DNA interaction was proposed for them. In addition, molecular docking results indicated that there are three types of bonds (Hsbnd and X-bond and hX-bond) between synthesized compounds and base pairs of DNA.

  16. Anti-Inflammatory Activity of Different Agave Plants and the Compound Cantalasaponin-1

    Directory of Open Access Journals (Sweden)

    Jaime Tortoriello

    2013-07-01

    Full Text Available Species of the agave genus, such as Agave tequilana, Agave angustifolia and Agave americana are used in Mexican traditional medicine to treat inflammation-associated conditions. These plants’ leaves contain saponin compounds which show anti-inflammatory properties in different models. The goal of this investigation was to evaluate the anti-inflammatory capacity of these plants, identify which is the most active, and isolate the active compound by a bio-directed fractionation using the ear edema induced in mice with 12-O-tetradecanoylphorbol-13-acetate (TPA technique. A dose of 6 mg/ear of acetone extract from the three agave species induced anti-inflammatory effects, however, the one from A. americana proved to be the most active. Different fractions of this species showed biological activity. Finally the F5 fraction at 2.0 mg/ear induced an inhibition of 85.6%. We identified one compound in this fraction as (25R-5α-spirostan-3β,6α,23α-triol-3,6-di-O-β-D-glucopyranoside (cantalasaponin-1 through 1H- and 13C-NMR spectral analysis and two dimensional experiments like DEPT NMR, COSY, HSQC and HMBC. This steroidal glycoside showed a dose dependent effect of up to 90% of ear edema inhibition at the highest dose of 1.5 mg/ear.

  17. Compound refractive X-ray lens

    International Nuclear Information System (INIS)

    Nygren, D.R.; Cahn, R.; Cederstrom, B.; Danielsson, M.; Vestlund, J.

    2000-01-01

    An apparatus and method are disclosed for focusing X-rays. In one embodiment, his invention is a commercial-grade compound refractive X-ray lens. The commercial-grade compound refractive X-ray lens includes a volume of low-Z material. The volume of low-Z material has a first surface which is adapted to receive X-rays of commercially-applicable power emitted from a commercial-grade X-ray source. The volume of low-Z material also has a second surface from which emerge the X-rays of commercially-applicable power which were received at the first surface. Additionally, the commercial-grade compound refractive X-ray lens includes a plurality of openings which are disposed between the first surface and the second surface. The plurality of openings are oriented such that the X-rays of commercially-applicable power which are received at the first surface, pass through the volume of low-Z material and through the plurality openings. In so doing, the X-rays which emerge from the second surface are refracted to a focal point

  18. Compound refractive X-ray lens

    Science.gov (United States)

    Nygren, David R.; Cahn, Robert; Cederstrom, Bjorn; Danielsson, Mats; Vestlund, Jonas

    2000-01-01

    An apparatus and method for focusing X-rays. In one embodiment, his invention is a commercial-grade compound refractive X-ray lens. The commercial-grade compound refractive X-ray lens includes a volume of low-Z material. The volume of low-Z material has a first surface which is adapted to receive X-rays of commercially-applicable power emitted from a commercial-grade X-ray source. The volume of low-Z material also has a second surface from which emerge the X-rays of commercially-applicable power which were received at the first surface. Additionally, the commercial-grade compound refractive X-ray lens includes a plurality of openings which are disposed between the first surface and the second surface. The plurality of openings are oriented such that the X-rays of commercially-applicable power which are received at the first surface, pass through the volume of low-Z material and through the plurality openings. In so doing, the X-rays which emerge from the second surface are refracted to a focal point.

  19. 2-(Substituted phenyl-3,4-dihydroisoquinolin-2-iums as Novel Antifungal Lead Compounds: Biological Evaluation and Structure-Activity Relationships

    Directory of Open Access Journals (Sweden)

    Xin-Juan Yang

    2013-08-01

    Full Text Available The title compounds are a class of structurally simple analogues of quaternary benzo[c]phenanthridine alkaloids (QBAs. In order to develop novel QBA-like antifungal drugs, in this study, 24 of the title compounds with various substituents on the N-phenyl ring were evaluated for bioactivity against seven phytopathogenic fungi using the mycelial growth rate method and their SAR discussed. Almost all the compounds showed definite activities in vitro against each of the test fungi at 50 μg/mL and a broad antifungal spectrum. In most cases, the mono-halogenated compounds 2–12 exhibited excellent activities superior to the QBAs sanguinarine and chelerythrine. Compound 8 possessed the strongest activities on each of the fungi with EC50 values of 8.88–19.88 µg/mL and a significant concentration-dependent relationship. The SAR is as follows: the N-phenyl group is a high sensitive structural moiety for the activity and the characteristics and position of substituents intensively influence the activity. Generally, electron-withdrawing substituents remarkably enhance the activity while electron-donating substituents cause a decrease of the activity. In most cases, ortha- and para-halogenated isomers were more active than the corresponding m-halogenated isomers. Thus, the title compounds emerged as promising lead compounds for the development of novel biomimetic antifungal agrochemicals. Compounds 8 and 2 should have great potential as new broad spectrum antifungal agents for plant protection.

  20. Phenolic Compounds from Halimodendron halodendron (Pall. Voss and Their Antimicrobial and Antioxidant Activities

    Directory of Open Access Journals (Sweden)

    Jihua Wang

    2012-09-01

    Full Text Available Halimodendron halodendron has been used as forage in northwestern China for a long time. Its young leaves and flowers are edible and favored by indigenous people. In this study, eleven phenolic compounds were bioassay-guided and isolated from the aerial parts of H. halodendron for the first time. They were identified by means of physicochemical and spectrometric analysis as quercetin (1, 3,5,7,8,4'-pentahydroxy-3'-methoxy flavone (2, 3-O-methylquercetin (3, 3,3'-di-O-methylquercetin (4, 3,3'-di-O-methylquercetin-7-O-β-D-glucopyranoside (5, isorhamentin-3-O-β-D-rutinoside (6, 8-O-methylretusin (7, 8-O-methylretusin-7-O-β-D-glucopyranoside (8, salicylic acid (9, p-hydroxybenzoic acid (ferulic acid (10, and 4-hydroxy-3-methoxy cinnamic acid (11. They were sorted as flavonols (1–6, soflavones (7 and 8, and phenolic acids (9–11. Among the compounds, flanools 1–4 revealed a strong antibacterial activity with minimum inhibitory concentration (MIC values of 50–150 μg/mL, and median inhibitory concentration (IC50 values of 26.8–125.1 μg/mL. The two isoflavones (7 and 8 showed moderate inhibitory activity on the test bacteria. Three phenolic acids (9, 10 and 11 showed strong antibacterial activity with IC50 values of 28.1–149.7 μg/mL. Antifungal activities of the compounds were similar to their antibacterial activities. All these phenolic compounds showed significant antimicrobial activity with a broad spectrum as well as antioxidant activity based on 1,1-diphenyl-2-picrylhydrazyl (DPPH radical scavenging and β-carotene-linoleic acid bleaching assays. In general, the flavonol aglycones with relatively low polarity exhibited stronger activities than the glycosides. The results suggest the potential of this plant as a source of functional food ingredients and provide support data for its utilization as forage as well.

  1. High-Throughput Gene Expression Profiles to Define Drug Similarity and Predict Compound Activity.

    Science.gov (United States)

    De Wolf, Hans; Cougnaud, Laure; Van Hoorde, Kirsten; De Bondt, An; Wegner, Joerg K; Ceulemans, Hugo; Göhlmann, Hinrich

    2018-04-01

    By adding biological information, beyond the chemical properties and desired effect of a compound, uncharted compound areas and connections can be explored. In this study, we add transcriptional information for 31K compounds of Janssen's primary screening deck, using the HT L1000 platform and assess (a) the transcriptional connection score for generating compound similarities, (b) machine learning algorithms for generating target activity predictions, and (c) the scaffold hopping potential of the resulting hits. We demonstrate that the transcriptional connection score is best computed from the significant genes only and should be interpreted within its confidence interval for which we provide the stats. These guidelines help to reduce noise, increase reproducibility, and enable the separation of specific and promiscuous compounds. The added value of machine learning is demonstrated for the NR3C1 and HSP90 targets. Support Vector Machine models yielded balanced accuracy values ≥80% when the expression values from DDIT4 & SERPINE1 and TMEM97 & SPR were used to predict the NR3C1 and HSP90 activity, respectively. Combining both models resulted in 22 new and confirmed HSP90-independent NR3C1 inhibitors, providing two scaffolds (i.e., pyrimidine and pyrazolo-pyrimidine), which could potentially be of interest in the treatment of depression (i.e., inhibiting the glucocorticoid receptor (i.e., NR3C1), while leaving its chaperone, HSP90, unaffected). As such, the initial hit rate increased by a factor 300, as less, but more specific chemistry could be screened, based on the upfront computed activity predictions.

  2. Antimicrobial activity of crude fractions and morel compounds from wild edible mushrooms of North western Himalaya.

    Science.gov (United States)

    Shameem, Nowsheen; Kamili, Azra N; Ahmad, Mushtaq; Masoodi, F A; Parray, Javid A

    2017-04-01

    The antimicrobial properties of morel compounds from wild edible mushrooms (Morchella esculenta and Verpa bohemica) from Kashmir valley was investigated against different clinical pathogens. The butanol crude fraction of most popular or true morel M. esculenta showed highest 19 mm IZD against E.coli while as same fraction of Verpa bohemica exhibited 15 mm IZD against same strain. The ethyl acetate and butanol crude fractions of both morels also exhibited good antifungal activity with highest IZD shown against A. fumigates. The three morel compounds showed quite impressive anti bacterial and fungal activities. The Cpd 3 showed highest inhibitory activity almost equivalent to the synthetic antibiotics used as control. The MIC/MBC values revealed the efficiency of isolated compounds against the pathogenic strains. In the current study significant inhibitory activity of morel compounds have been obtained paying the way for their local use from ancient times. Copyright © 2017. Published by Elsevier Ltd.

  3. Laterally injected light-emitting diode and laser diode

    Science.gov (United States)

    Miller, Mary A.; Crawford, Mary H.; Allerman, Andrew A.

    2015-06-16

    A p-type superlattice is used to laterally inject holes into an III-nitride multiple quantum well active layer, enabling efficient light extraction from the active area. Laterally-injected light-emitting diodes and laser diodes can enable brighter, more efficient devices that impact a wide range of wavelengths and applications. For UV wavelengths, applications include fluorescence-based biological sensing, epoxy curing, and water purification. For visible devices, applications include solid state lighting and projection systems.

  4. Anti-BACE1 and Antimicrobial Activities of Steroidal Compounds Isolated from Marine Urechis unicinctus

    Directory of Open Access Journals (Sweden)

    Yong-Zhe Zhu

    2018-03-01

    Full Text Available The human β-site amyloid cleaving enzyme (BACE1 has been considered as an effective drug target for treatment of Alzheimer’s disease (AD. In this study, Urechis unicinctus (U. unicinctus, which is a Far East specialty food known as innkeeper worm, ethanol extract was studied by bioassay-directed fractionation and isolation to examine its potential β-site amyloid cleaving enzyme inhibitory and antimicrobial activity. The following compounds were characterized: hecogenin, cholest-4-en-3-one, cholesta-4,6-dien-3-ol, and hurgadacin. These compounds were identified by their mass spectrometry, 1H, and 13C NMR spectral data, comparing those data with NIST/EPA/NIH Mass spectral database (NIST11 and published values. Hecogenin and cholest-4-en-3-one showed significant inhibitory activity against BACE1 with EC50 values of 116.3 and 390.6 µM, respectively. Cholesta-4,6-dien-3-ol and hurgadacin showed broad spectrum antimicrobial activity, particularly strongly against Escherichia coli (E. coli, Salmonella enterica (S. enterica, Pasteurella multocida (P. multocida, and Physalospora piricola (P. piricola, with minimal inhibitory concentration (MIC ranging from 0.46 to 0.94 mg/mL. This is the first report regarding those four known compounds that were isolated from U. unicinctus and their anti-BACE1 and antimicrobial activity, highlighting the fact that known natural compounds may be a critical source of new medicine leads. These findings provide scientific evidence for potential application of those bioactive compounds for the development of AD drugs and antimicrobial agents.

  5. Anti-BACE1 and Antimicrobial Activities of Steroidal Compounds Isolated from Marine Urechis unicinctus.

    Science.gov (United States)

    Zhu, Yong-Zhe; Liu, Jing-Wen; Wang, Xue; Jeong, In-Hong; Ahn, Young-Joon; Zhang, Chuan-Jie

    2018-03-14

    The human β-site amyloid cleaving enzyme (BACE1) has been considered as an effective drug target for treatment of Alzheimer's disease (AD). In this study, Urechis unicinctus (U. unicinctus) , which is a Far East specialty food known as innkeeper worm, ethanol extract was studied by bioassay-directed fractionation and isolation to examine its potential β-site amyloid cleaving enzyme inhibitory and antimicrobial activity. The following compounds were characterized: hecogenin, cholest-4- en -3-one, cholesta-4,6- dien -3-ol, and hurgadacin. These compounds were identified by their mass spectrometry, ¹H, and 13 C NMR spectral data, comparing those data with NIST/EPA/NIH Mass spectral database (NIST11) and published values. Hecogenin and cholest-4- en -3-one showed significant inhibitory activity against BACE1 with EC 50 values of 116.3 and 390.6 µM, respectively. Cholesta-4,6- dien -3-ol and hurgadacin showed broad spectrum antimicrobial activity, particularly strongly against Escherichia coli (E. coli) , Salmonella enterica (S. enterica) , Pasteurella multocida (P. multocida) , and Physalospora piricola (P. piricola) , with minimal inhibitory concentration (MIC) ranging from 0.46 to 0.94 mg/mL. This is the first report regarding those four known compounds that were isolated from U. unicinctus and their anti-BACE1 and antimicrobial activity, highlighting the fact that known natural compounds may be a critical source of new medicine leads. These findings provide scientific evidence for potential application of those bioactive compounds for the development of AD drugs and antimicrobial agents.

  6. Volatile Organic Compound (VOC) Air Monitoring Program design for the Waste Isolation Pilot Plant

    International Nuclear Information System (INIS)

    Frank, L.

    1991-01-01

    The Waste Isolation Pilot Plant (WIPP) Volatile Organic Compound (VOC) Monitoring Program has been developed as part of the Department of Energy's (DOE's) No-Migration Variance petition submitted to the Environmental Protection Agency (EPA). The program is designed to demonstrate that there will be no migration of hazardous chemicals past the unit boundary in concentrations which exceed any health-based standards. The monitoring program will use EPA compendium Method TO-14. Both air and carbon sorption media samples will be collected as part of the program. Eleven separate monitoring sites have been selected where both 24-hour integrated and 1-hour grab samples will be collected and analyzed for five target compounds. The bin-scale experimental test rooms will be configured with a gas collection manifold and an activated carbon sorption bed to remove VOCs before they can be emitted into the WIPP underground atmosphere. 10 refs., 4 figs., 7 tabs

  7. Contact-based ligand-clustering approach for the identification of active compounds in virtual screening

    Directory of Open Access Journals (Sweden)

    Mantsyzov AB

    2012-09-01

    Full Text Available Alexey B Mantsyzov,1 Guillaume Bouvier,2 Nathalie Evrard-Todeschi,1 Gildas Bertho11Université Paris Descartes, Sorbonne, Paris, France; 2Institut Pasteur, Paris, FranceAbstract: Evaluation of docking results is one of the most important problems for virtual screening and in silico drug design. Modern approaches for the identification of active compounds in a large data set of docked molecules use energy scoring functions. One of the general and most significant limitations of these methods relates to inaccurate binding energy estimation, which results in false scoring of docked compounds. Automatic analysis of poses using self-organizing maps (AuPosSOM represents an alternative approach for the evaluation of docking results based on the clustering of compounds by the similarity of their contacts with the receptor. A scoring function was developed for the identification of the active compounds in the AuPosSOM clustered dataset. In addition, the AuPosSOM efficiency for the clustering of compounds and the identification of key contacts considered as important for its activity, were also improved. Benchmark tests for several targets revealed that together with the developed scoring function, AuPosSOM represents a good alternative to the energy-based scoring functions for the evaluation of docking results.Keywords: scoring, docking, virtual screening, CAR, AuPosSOM

  8. IDENTIFICATION AND ANTIOXIDANT ACTIVITY TEST OF SOME COMPOUNDS FROM METHANOL EXTRACT PEEL OF BANANA (Musa paradisiaca Linn.

    Directory of Open Access Journals (Sweden)

    Sri Atun

    2010-06-01

    Full Text Available The objective of these research was measured activity as antioxidant some compounds in methanol extracts of peel of banana (Musa paradisiaca Linn., isolated some compounds which had activities as antioxidant, and determined this structure. Method of this study was extracted powdered peel of banana with methanol at room temperature. Extract was concentrated in vaccuo and then successively was partitioned with n-hexane, chloroform, etyl acetate, and buthanol. Antioxidant test from each fractions was measured by hydroxyl radical scavenger test with Fenton reaction method. The result of this study showed activity each fractions as  hydroxyl radical scavenger activity of chloroform, etyl acetate, and buthanol fraction were IC50 693.15; 2347.40; and 1071.14 mg/mL respectively. The isolation of secondary metabolite compounds from chloroform fraction obtained two isolate compounds. Identification by spectroscopy IR,  MS, 1H and 13C NMR one and two dimension showed that the compounds are 5,6,7,4'-tetrahidroxy-3,4-flavan-diol and a new compound cyclohexenon derivative (2-cyclohexene-1-on-2,4,4-trimethyl-3-O-2'-hydroxypropyl ether.   Keywords: antioxidant, peel of banana, Musa paradisiaca, hydroxyl radical scavenger

  9. Design of cinnamaldehyde amino acid Schiff base compounds based on the quantitative structure–activity relationship

    Science.gov (United States)

    Hui Wang; Mingyue Jiang; Shujun Li; Chung-Yun Hse; Chunde Jin; Fangli Sun; Zhuo Li

    2017-01-01

    Cinnamaldehyde amino acid Schiff base (CAAS) is a new class of safe, bioactive compounds which could be developed as potential antifungal agents for fungal infections. To design new cinnamaldehyde amino acid Schiff base compounds with high bioactivity, the quantitative structure–activity relationships (QSARs) for CAAS compounds against Aspergillus niger (A. niger) and...

  10. Development and therapeutic application of internally emitting radiopharmaceuticals

    International Nuclear Information System (INIS)

    Adelstein, S.J.; Bloomer, W.D.

    1980-01-01

    This project is concerned with developing the potential of alpha-emitting radionuclides as agents for radiotherapy. Among the available α-emitters, astatine-211 appears most promising for testing the efficacy of α-emitters for therapeutic applications because: (1) it has some chemical similarities to iodine, an element that can readily be incorporated into numerous proteins and peptides; (2) it has a half life that is long enough to permit chemical manipulation yet short enough to minimize destruction of healthy cells; and (3) α-emission is associated with 100% of its decays. If appropriate biological carriers can be labeled with an alpha emitter such as 211 At, they could be of great utility in several areas of therapeutic medicine where elimination of specific cell populations is desired. While previous attempts to astatinate proteins using standard iodination techniques have been unsuccessful, effective labeling of proteins with astatine by first synthesizing an aryl astatide and then coupling this compound to the protein via an acylation has been achieved. Undergoing current investigation are several different aryl astatide-followed-by-acylation approaches including an astatinated Bolton-Hunter type reagent using concanavalin A (ConA) and melanocyte stimulating hormone (MSH) as model compounds

  11. Radiation emitting devices regulations

    International Nuclear Information System (INIS)

    1970-01-01

    The Radiation Emitting Devices Regulations are the regulations referred to in the Radiation Emitting Devices Act and relate to the operation of devices. They include standards of design and construction, standards of functioning, warning symbol specifications in addition to information relating to the seizure and detention of machines failing to comply with the regulations. The radiation emitting devices consist of the following: television receivers, extra-oral dental x-ray equipment, microwave ovens, baggage inspection x-ray devices, demonstration--type gas discharge devices, photofluorographic x-ray equipment, laser scanners, demonstration lasers, low energy electron microscopes, high intensity mercury vapour discharge lamps, sunlamps, diagnostic x-ray equipment, ultrasound therapy devices, x-ray diffraction equipment, cabinet x-ray equipment and therapeutic x-ray equipment

  12. Bioactive compounds, antioxidant and binding activities and spear yield of Asparagus officinalis L.

    Science.gov (United States)

    Lee, Jong Won; Lee, Jeong Hyun; Yu, In Ho; Gorinstein, Shela; Bae, Jong Hyang; Ku, Yang Gyu

    2014-06-01

    The aim of this investigation was to find a proper harvesting period and establishing fern number, which effects the spear yield, bioactive compounds and antioxidant activities of Asparagus officinalis L. Spears were harvested at 2, 4, and 6 weeks after sprouting. Control for comparison was used without harvest. Spears and total yield increased with prolonged spear harvest period. In harvest of 6 weeks long optimum spear yield was the highest and fern numbers were 5 ~ 8. Bioactive compounds (polyphenols, flavonoids, flavanols, tannins and ascorbic acid) and the levels of antioxidant activities by ferric-reducing/antioxidant power (FRAP) and cupric reducing antioxidant capacity (CUPRAC) assays in asparagus ethanol extracts significantly differed in the investigated samples and were the highest at 6 weeks harvest period (P asparagus were studied by the interaction of polyphenol ethanol extracts with HSA, using 3D- FL. In conclusion, antioxidant status (bioactive compounds, binding and antioxidant activities) improved with the harvesting period and the first segment from spear tip. Appropriate harvesting is effective for higher asparagus yield and its bioactivity.

  13. Acquisition of compound words in Chinese-English bilingual children: Decomposition and cross-language activation

    NARCIS (Netherlands)

    Cheng, C.; Wang, M.; Perfetti, C.A.

    2011-01-01

    This study investigated compound processing and cross-language activation in a group of Chinese–English bilingual children, and they were divided into four groups based on the language proficiency levels in their two languages. A lexical decision task was designed using compound words in both

  14. Simultaneous multi-wavelength ultraviolet excited single-phase white light emitting phosphor Ba1-x(Zr,Ti)Si3O9:xEu

    Science.gov (United States)

    Zhou, Zhenzhen; Liu, Guanghui; Ni, Jia; Liu, Wanlu; Liu, Qian

    2018-05-01

    A kind of novel compound Ba1-x(Zr,Ti)Si3O9:xEu simultaneously activated by different-valence Eu2+ and Eu3+ ions has been successfully synthesized. The existence of Ti4+-O2- charge transfer (CT) transitions in Ba1-xZrSi3O9:xEu is proved by the photoluminescence spectra and first principle calculations, and the Ti4+ ions come from the impurities in commercial ZrO2 raw materials. Under the excitation of multi-wavelength ultraviolet radiation (λEX = 392, 260, 180 nm), Ba1-xZrSi3O9:xEu (x = 0.15) can directly emit nearly white light. The coexistence of multiple luminescent centers and the energy transfer among Zr4+-O2- CT state, Ti4+-O2- CT state, Eu2+ and Eu3+ ions play important roles in the white light emission. Ba1-xZrSi3O9:xEu (x = 0.15) has good thermal stability, in particular, the intensity of emission spectrum (λEX = 392 nm) at 150 °C is ∼96% of that at room temperature. In general, the multi-wavelength ultraviolet-excited single-phase white light emitting phosphor Ba1-x(Zr,Ti)Si3O9:xEu possesses a promise for applications in white light emitting diodes (WLEDs), agriculture, medicine and other photonic fields.

  15. Exploring sets of molecules from patents and relationships to other active compounds in chemical space networks

    Science.gov (United States)

    Kunimoto, Ryo; Bajorath, Jürgen

    2017-09-01

    Patents from medicinal chemistry represent a rich source of novel compounds and activity data that appear only infrequently in the scientific literature. Moreover, patent information provides a primary focal point for drug discovery. Accordingly, text mining and image extraction approaches have become hot topics in patent analysis and repositories of patent data are being established. In this work, we have generated network representations using alternative similarity measures to systematically compare molecules from patents with other bioactive compounds, visualize similarity relationships, explore the chemical neighbourhood of patent molecules, and identify closely related compounds with different activities. The design of network representations that combine patent molecules and other bioactive compounds and view patent information in the context of current bioactive chemical space aids in the analysis of patents and further extends the use of molecular networks to explore structure-activity relationships.

  16. Design, synthesis, antiviral activity and mode of action of phenanthrene-containing N-heterocyclic compounds inspired by the phenanthroindolizidine alkaloid antofine.

    Science.gov (United States)

    Yu, Xiuling; Wei, Peng; Wang, Ziwen; Liu, Yuxiu; Wang, Lizhong; Wang, Qingmin

    2016-02-01

    The phenanthroindolizidine alkaloid antofine and its analogues have excellent antiviral activity against tobacco mosaic virus (TMV). To simplify the structure and the synthesis of the phenanthroindolizidine alkaloid, a series of phenanthrene-containing N-heterocyclic compounds (compounds 1 to 33) were designed and synthesised, based on the intermolecular interaction of antofine and TMV RNA, and systematically evaluated for their anti-TMV activity. Most of these compounds exhibited good to reasonable anti-TMV activity. The optimum compounds 5, 12 and 21 displayed higher activity than the lead compound antofine and commercial ribavirin. Compound 12 was chosen for field trials of antiviral efficacy against TMV, and was found to exhibit better activity than control plant virus inhibitors. Compounds 5 and 12 were chosen for mode of action studies. The changes in fluorescence intensity of compounds 5 and 12 on separated TMV RNA showed that these small molecules can also bind to TMV RNA, but the mode is very different from that of antofine. The compounds combining phenanthrene and an N-heterocyclic ring could maintain the anti-TMV activity of phenanthroindolizidines, but their modes of action are different from that of antofine. The present study lays a good foundation for us to find more efficient anti-plant virus reagents. © 2015 Society of Chemical Industry.

  17. A community computational challenge to predict the activity of pairs of compounds.

    Science.gov (United States)

    Bansal, Mukesh; Yang, Jichen; Karan, Charles; Menden, Michael P; Costello, James C; Tang, Hao; Xiao, Guanghua; Li, Yajuan; Allen, Jeffrey; Zhong, Rui; Chen, Beibei; Kim, Minsoo; Wang, Tao; Heiser, Laura M; Realubit, Ronald; Mattioli, Michela; Alvarez, Mariano J; Shen, Yao; Gallahan, Daniel; Singer, Dinah; Saez-Rodriguez, Julio; Xie, Yang; Stolovitzky, Gustavo; Califano, Andrea

    2014-12-01

    Recent therapeutic successes have renewed interest in drug combinations, but experimental screening approaches are costly and often identify only small numbers of synergistic combinations. The DREAM consortium launched an open challenge to foster the development of in silico methods to computationally rank 91 compound pairs, from the most synergistic to the most antagonistic, based on gene-expression profiles of human B cells treated with individual compounds at multiple time points and concentrations. Using scoring metrics based on experimental dose-response curves, we assessed 32 methods (31 community-generated approaches and SynGen), four of which performed significantly better than random guessing. We highlight similarities between the methods. Although the accuracy of predictions was not optimal, we find that computational prediction of compound-pair activity is possible, and that community challenges can be useful to advance the field of in silico compound-synergy prediction.

  18. Anti-equine arteritis virus activity of ethanolic extract and compounds from Origanum vulgare

    Directory of Open Access Journals (Sweden)

    Daiane Einhardt Blank

    2017-05-01

    Full Text Available The equine arteritis virus (EAV is responsible by an important respiratory and reproductive disease in equine populations and there is no specific antiviral treatment available. The objective of this study was to investigate the activity of an ethanolic crude extract of Origanum vulgare (EEO and of isolated compound caffeic acid, p-coumaric acid, rosmarinic acid, quercetin, luteolin, carnosol, carnosic acid, kaempferol and apigenin against EAV. The assays were performed using non-cytotoxic concentrations. The antiviral activity was monitored initially by cytopathic effect inhibition (CPE assay in RK13 cells in the presence or absence of EEO. Pre-incubated cells with EEO were also examined to show prophylactic effect. Direct viral inactivation by EEO and isolated compounds was evaluated by incubation at 37°C or 20°C. After the incubation period, the infectivity was immediately determined by virus titrations on cell cultures and expressed as 50% tissue culture infective dose (TCID50/100 µL. There was significant virucidal activity of EEO and of the compounds caffeic acid, p-coumaric acid, quercetin, carnosic acid and kaempferol. When EEO was added after infection, EEO inhibited the virus growth in infected cells, as evidenced by significant reduction of the viral titre. The results provide evidence that the EEO exhibit an inhibitory effect anti-EAV. Among the main compounds evaluated, caffeic acid, p-coumaric acid, carnosic acid, kaempferol and mainly quercetin, contributed to the activity of EEO. EEO may represent a good prototype for the development of a new antiviral agent, presenting promising for combating arteriviruses infections.

  19. Screening for Antiviral Activities of Isolated Compounds from Essential Oils

    Directory of Open Access Journals (Sweden)

    Akram Astani

    2011-01-01

    Full Text Available Essential oil of star anise as well as phenylpropanoids and sesquiterpenes, for example, trans-anethole, eugenol, β-eudesmol, farnesol, β-caryophyllene and β-caryophyllene oxide, which are present in many essential oils, were examined for their antiviral activity against herpes simplex virus type 1 (HSV-1 in vitro. Antiviral activity was analyzed by plaque reduction assays and mode of antiviral action was determined by addition of the drugs to uninfected cells, to the virus prior to infection or to herpesvirus-infected cells. Star anise oil reduced viral infectivity by >99%, phenylpropanoids inhibited HSV infectivity by about 60–80% and sesquiterpenes suppressed herpes virus infection by 40–98%. Both, star anise essential oil and all isolated compounds exhibited anti-HSV-1 activity by direct inactivation of free virus particles in viral suspension assays. All tested drugs interacted in a dose-dependent manner with herpesvirus particles, thereby inactivating viral infectivity. Star anise oil, rich in trans-anethole, revealed a high selectivity index of 160 against HSV, whereas among the isolated compounds only β-caryophyllene displayed a high selectivity index of 140. The presence of β-caryophyllene in many essential oils might contribute strongly to their antiviral ability. These results indicate that phenylpropanoids and sesquiterpenes present in essential oils contribute to their antiviral activity against HSV.

  20. Biogenic volatile organic compound (BVOC) emissions from forested areas in Turkey: determination of specific emission rates for thirty-one tree species.

    Science.gov (United States)

    Aydin, Yagmur Meltem; Yaman, Baris; Koca, Husnu; Dasdemir, Okan; Kara, Melik; Altiok, Hasan; Dumanoglu, Yetkin; Bayram, Abdurrahman; Tolunay, Doganay; Odabasi, Mustafa; Elbir, Tolga

    2014-08-15

    Normalized biogenic volatile organic compound (BVOC) emission rates for thirty one tree species that cover the 98% of national forested areas in Turkey were determined. Field samplings were performed at fourteen different forested areas in Turkey using a specific dynamic enclosure system. The selected branches of tree species were enclosed in a chamber consisted of a transparent Nalofan bag. The air-flows were sampled from both inlet and outlet of the chamber by Tenax-filled sorbent tubes during photosynthesis of trees under the presence of sunlight. Several environmental parameters (temperature, humidity, photosynthetically active radiation-PAR, and CO2) were continuously monitored inside and outside the enclosure chamber during the samplings. Collected samples were analyzed using a gas chromatography mass spectrometry (GC/MS) system equipped with a thermal desorber (TD). Sixty five BVOCs classified in five major groups (isoprene, monoterpenes, sesquiterpenes, oxygenated sesquiterpenes, and other oxygenated compounds) were analyzed. Emission rates were determined by normalization to standard conditions (1000 μmol/m(2)s PAR and 30 °C temperature for isoprene and 30 °C temperature for the remaining compounds). In agreement with the literature, isoprene was mostly emitted by broad-leaved trees while coniferous species mainly emitted monoterpenes. Several tree species such as Sweet Chestnut, Silver Lime, and European Alder had higher monoterpene emissions although they are broad-leaved species. High isoprene emissions were also observed for a few coniferous species such as Nordmann Fir and Oriental Spruce. The highest normalized total BVOC emission rate of 27.1 μg/gh was observed for Oriental Plane while South European Flowering Ash was the weakest BVOC emitter with a total normalized emission rate of 0.031 μg/gh. Monoterpene emissions of broad-leaved species mainly consisted of sabinene, limonene and trans-beta-ocimene, while alpha-pinene, beta-pinene and beta

  1. Study of photophysical processes in organic light-emitting diodes based on light-emission profile reconstruction

    NARCIS (Netherlands)

    Carvelli, M.

    2012-01-01

    Organic light-emitting diodes (OLEDs) are emerging as a promising option for energy-efficient, flexible light sources. A key factor that needs to be measured and controlled is the shape of the emission profile, i.e. the spatial distribution of the emitting excitons across the active layer thickness.

  2. Antitumor activity of extract and isolated compounds from Drechslera rostrata and Eurotium tonophilum

    Directory of Open Access Journals (Sweden)

    Fatmah A.S. Alasmary

    2018-02-01

    Full Text Available Total extracts of Drechslera rostrata and Eurotium tonophilum in addition of two isolated compounds from their cultures [di-2-ethylhexyl phthalate (H1 and 1,8-Dihydroxy-3-methoxy-6-methyl-anthraquinone (H2] were tested for their antitumor activity using four human carcinoma cell lines. Antitumor activity was assessed by performing MTT assay to check the % cell viability. The % viability of HCT-116 (colon carcinoma, HeLa (cervical carcinoma, HEp-2 (larynx carcinoma and HepG-2 (hepatocellular carcinoma cells decreased after treatment with Drechslera rostrata and Eurotium tonophilum extracts, these effects were ranged from 059.0 ±  0.1 to 217.0  ±  0.3 µg/ml on all types of cancer cells. The best activity was recorded for Eurotium tonpholium extract (054.5 ± 0.3, 059.0 ± 0.5 and 059.0 ± 0.1 for HEp-2, Hela, and HepG-2 respectively. The isolated compounds (H1&H2 were found to be responsible about the activities because they recorded the lowest IC50 on tested cell lines with range of 9.5–20.3 μg/ml. Vinblastine sulphate was used as a reference standard and showed in vitro anticancer activity. This study demonstrated that all extracts and isolated compounds have antitumor activity against HCT-116, HeLa, HEp-2 and HepG-2 cells.

  3. A SAR and QSAR study of new artemisinin compounds with antimalarial activity.

    Science.gov (United States)

    Santos, Cleydson Breno R; Vieira, Josinete B; Lobato, Cleison C; Hage-Melim, Lorane I S; Souto, Raimundo N P; Lima, Clarissa S; Costa, Elizabeth V M; Brasil, Davi S B; Macêdo, Williams Jorge C; Carvalho, José Carlos T

    2013-12-30

    The Hartree-Fock method and the 6-31G** basis set were employed to calculate the molecular properties of artemisinin and 20 derivatives with antimalarial activity. Maps of molecular electrostatic potential (MEPs) and molecular docking were used to investigate the interaction between ligands and the receptor (heme). Principal component analysis and hierarchical cluster analysis were employed to select the most important descriptors related to activity. The correlation between biological activity and molecular properties was obtained using the partial least squares and principal component regression methods. The regression PLS and PCR models built in this study were also used to predict the antimalarial activity of 30 new artemisinin compounds with unknown activity. The models obtained showed not only statistical significance but also predictive ability. The significant molecular descriptors related to the compounds with antimalarial activity were the hydration energy (HE), the charge on the O11 oxygen atom (QO11), the torsion angle O1-O2-Fe-N2 (D2) and the maximum rate of R/Sanderson Electronegativity (RTe+). These variables led to a physical and structural explanation of the molecular properties that should be selected for when designing new ligands to be used as antimalarial agents.

  4. The importance of extremophile cyanobacteria in the production of biologically active compounds

    Directory of Open Access Journals (Sweden)

    Drobac-Čik Aleksandra V.

    2007-01-01

    Full Text Available Due to their ability to endure extreme conditions, terrestrial cyanobacteria belong to a group of organisms known as "extremophiles". Research so far has shown that these organisms posses a great capacity for producing biologically active compounds (BAC. The antibacterial and antifungal activities of methanol extracts of 21 cyanobacterial strains belonging to Anabaena and Nostoc genera, previously isolated from different soil types and water resources in Serbia, were evaluated. In general, larger number of cyanobacterial strains showed antifungal activity. In contrast to Nostoc, Anabaena strains showed greater diversity of antibacterial activity (mean value of percentages of sensitive targeted bacterial strains 3% and 25.9% respectively. Larger number of targeted fungi was sensitive to cultural liquid extract (CL, while crude cell extract (CE affected more bacterial strains. According to this investigation, the higher biological activity of terrestrial strains as representatives of extremophiles may present them as significant BAC producers. This kind of investigation creates very general view of cyanobacterial possibility to produce biologically active compounds but it points out the necessity of exploring terrestrial cyanobacterial extremophiles as potentially excellent sources of these substances and reveals the most prospective strains for further investigations.

  5. Facile determination of the specific activity of carbonyl compounds reduced by tritiated borohydride

    Energy Technology Data Exchange (ETDEWEB)

    Avigad, G [Rutgers--the State Univ., Piscataway, NJ (USA)

    1979-12-01

    Three procedures are described for microliter samples of glucose 6-phosphate or lactose as model compounds. After the reduction with (/sup 3/H)-NaBH/sub 4/ and suitable treatment, specific activity is calculated from the ratios /sup 3/H activity/total phosphorus, /sup 3/H//sup 14/C activity, or /sup 3/H activity/galactoside concentration.

  6. Antileishmanial Activity of the Hydroalcoholic Extract of Miconia langsdorffii, Isolated Compounds, and Semi-Synthetic Derivatives

    Directory of Open Access Journals (Sweden)

    Wilson R. Cunha

    2011-02-01

    Full Text Available The in vitro activity of the crude hydroalcoholic extract of the aerial parts of Miconia langsdorffii Cogn. was evaluated against the promastigote forms of L. amazonensis, the causative agent of cutaneous leishmaniasis in humans. The bioassay-guided fractionation of this extract led to identification of the triterpenes ursolic acid and oleanolic acid as the major compounds in the fraction that displayed the highest activity. Several ursolic acid semi-synthetic derivatives were prepared, to find out whether more active compounds could be obtained. Among these ursolic acid-derived substances, the C-28 methyl ester derivative exhibited the best antileishmanial activity.

  7. Identification of the functional binding pocket for compounds targeting small-conductance Ca2+-activated potassium channels

    Science.gov (United States)

    Zhang, Miao; Pascal, John M.; Schumann, Marcel; Armen, Roger S.; Zhang, Ji-fang

    2012-01-01

    Small- and intermediate-conductance Ca2+-activated potassium channels, activated by Ca2+-bound calmodulin, play an important role in regulating membrane excitability. These channels are also linked to clinical abnormalities. A tremendous amount of effort has been devoted to developing small molecule compounds targeting these channels. However, these compounds often suffer from low potency and lack of selectivity, hindering their potentials for clinical use. A key contributing factor is the lack of knowledge of the binding site(s) for these compounds. Here we demonstrate by X-ray crystallography that the binding pocket for the compounds of the 1-EBIO class is located at the calmodulin-channel interface. We show that, based on structure data and molecular docking, mutations of the channel can effectively change the potency of these compounds. Our results provide insight into the molecular nature of the binding pocket and its contribution to the potency and selectivity of the compounds of the 1-EBIO class. PMID:22929778

  8. Exploration of the anti-enterovirus activity of a series of pleconaril/pirodavir-like compounds.

    Science.gov (United States)

    Bernard, Angela; Lacroix, Céline; Cabiddu, Maria G; Neyts, Johan; Leyssen, Pieter; Pompei, Raffaello

    2015-04-01

    The Enterovirus genus of the Picornaviridae is represented by several viral pathogens that are associated with human disease, namely Poliovirus 1, Enterovirus 71 and Rhinoviruses. Enterovirus 71 has been associated with encephalitis, while Rhinoviruses are a major cause of asthma exacerbations and chronic obstructive pulmonary disease. Based on the structure of both pleconaril and pirodavir, we previously synthesized some original compounds as potential inhibitors of Rhinovirus replication. These compounds were explored for in vitro antiviral potential on other human pathogenic Enteroviruses, namely Enterovirus 71 on rhabdo-myosarcoma cells, Coxsackievirus B3 on Vero cells, Poliovirus 1 and Echovirus 11 on BGM cells. Activity was confirmed for compound against Rhinovirus 14. Furthermore, few compounds showed a cell-protective effect on Enterovirus 71, presented a marked improvement as compared to the reference drug pleconaril for inhibitory activity on both Enterovirus 71 and Poliovirus 1. The most striking observation was the clear cell protective effect for the set of analogues in a virus-cell-based assay for Echovirus 11 with an effective concentration (EC50) as low as 0.3 µM (Selectivity index or SI = 483), and selectivity indexes greater than 857 (EC50 = 0.6 µM) and 1524 (EC50 = 0.33 µM). Some of the evaluated compounds showed potent and selective antiviral activity against several enterovirus species, such as Enterovirus 71 (EV-A), Echovirus 11 (EV-B), and Poliovirus 1 (EV-C). This could be used as a starting point for the development of other pleconaril/pirodavir-like enterovirus inhibitors with broad-spectrum activity and improved effects as compared to the reference drugs. © The Author(s) 2015.

  9. Combined electrochemical degradation and activated carbon adsorption treatments for wastewater containing mixed phenolic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Rajkumar, D.; Palanivelu, K.; Balasubramanian, N. [Anna University, Madras (India). Center for Environmental Studies

    2005-01-01

    Electrochemical degradation of mixed phenolic compounds present in coal conversion wastewater was investigated in the presence of chloride as supporting electrolyte. Initially, the degradation experiments were conducted separately with 300 mg/L of individual phenolic compound in the presence of 2500 mg/L chloride using Ti/TiO{sub 2}-RuO{sub 2}-IrO{sub 2} anode at 5.4 A/dm{sup 2} current density. Comparison of the experimental results of the chemical oxygen demand (COD) removal versus charge indicated that the order of decreasing COD removal for various phenolic compounds as catechol {gt} resorcinol {gt} m-cresol {gt} o-cresol {gt} phenol {gt} p-cresol. Degradation of the mixture of phenolic compounds and high-pressure liquid chromatography (HPLC) determinations at various stages of electrolysis showed that phenolic compounds were initially converted into benzoquinone and then to lower molecular weight aliphatic compounds. The COD and the total organic carbon (TOC) removal were 83 and 58.9% after passing 32 Ah/L with energy consumption of 191.6 kWh/kg of COD removal. Experiments were also conducted to remove adsorbable organic halogens (AOX) content in the treated solution using granular activated carbon. The optimum conditions for the removal of AOX was at pH 3.0, 5 mL/min flow rate and 31.2 cm bed height. Based on the investigation, a general scheme of treatment of mixed phenolic compounds by combined electrochemical and activated carbon adsorption treatment is proposed.

  10. Hybrid white organic light-emitting devices consisting of a non-doped thermally activated delayed fluorescent emitter and an ultrathin phosphorescent emitter

    International Nuclear Information System (INIS)

    Zhao, Juan; Wang, Zijun; Wang, Run; Chi, Zhenguo; Yu, Junsheng

    2017-01-01

    Hybrid white organic light-emitting devices (OLEDs) are fabricated by employing non-doped emitting layers (EMLs), which are consisted of a blue thermally activated delayed fluorescent (TADF) emitter 9,9-dimethyl-9,10-dihydroacridine-diphenylsulfone (DMAC-DPS) and an ultrathin yellow iridium complex bis[2-(4-tertbutylphenyl)benzothiazolato-N,C 2′ ] iridium (acetylacetonate) [(tbt) 2 Ir(acac)]. With thickness optimization of DMAC-DPS, a white OLED achieves maximum current efficiency, power efficiency and external quantum efficiency of 34.9 cd/A, 29.2 lm/W and 11.4%, respectively, as well as warm white emission with relatively stable electroluminescence spectra. The results suggest that, bipolar charge carrier transport property and concentration independent property of DMAC-DPS, charge carrier trapping effect of the ultrathin (tbt) 2 Ir(acac), and balanced self-emission process and energy transfer process between DMAC-DPS and (tbt) 2 Ir(acac), contribute to high device performance.

  11. [The content of phenolic compounds and antioxidant activity ready to eat desserts for infants].

    Science.gov (United States)

    Filipiak-Florkiewicz, Agnieszka; Dereń, Katarzyna

    2011-01-01

    The aim of this study was to determine the content of phenolic compounds and antioxidant activity in ready-to-eat desserts for babies. The experimental material consisted of six kinds of fruit desserts taken from the market in 2008, in which the content of dry matter phenolic compounds and antioxidant activity levels on the basis of free radical quenching ability ABTS were determined. The largest share of dry matter was found in apricot mousse with apples and bananas (16.9%). The largest amounts of phenolic compounds were found in the cream with apple and wild rose (186.3 mg/100 g) and apple with forest fruits (170.7 mg/100 g). The highest antioxidant activity among the desserts was determined in cream with apple and wild rose (14.2 micromol Trolox/g) and apple mousse with peaches (12.8 micromol Trolox/g). The antioxidant capacity of the remaining examined purée was slightly lower and ranged from 11.4-11.7 micromol Trolox/g.

  12. Phenolic compounds and antioxidant activity of kernels and shells of Mexican pecan (Carya illinoinensis).

    Science.gov (United States)

    de la Rosa, Laura A; Alvarez-Parrilla, Emilio; Shahidi, Fereidoon

    2011-01-12

    The phenolic composition and antioxidant activity of pecan kernels and shells cultivated in three regions of the state of Chihuahua, Mexico, were analyzed. High concentrations of total extractable phenolics, flavonoids, and proanthocyanidins were found in kernels, and 5-20-fold higher concentrations were found in shells. Their concentrations were significantly affected by the growing region. Antioxidant activity was evaluated by ORAC, DPPH•, HO•, and ABTS•-- scavenging (TAC) methods. Antioxidant activity was strongly correlated with the concentrations of phenolic compounds. A strong correlation existed among the results obtained using these four methods. Five individual phenolic compounds were positively identified and quantified in kernels: ellagic, gallic, protocatechuic, and p-hydroxybenzoic acids and catechin. Only ellagic and gallic acids could be identified in shells. Seven phenolic compounds were tentatively identified in kernels by means of MS and UV spectral comparison, namely, protocatechuic aldehyde, (epi)gallocatechin, one gallic acid-glucose conjugate, three ellagic acid derivatives, and valoneic acid dilactone.

  13. Enrichment of Phenolic Compounds from Olive Mill Wastewater and In Vitro Evaluation of Their Antimicrobial Activities

    Directory of Open Access Journals (Sweden)

    Saleh Abu-Lafi

    2017-01-01

    Full Text Available The production of olive oil generates massive quantities of by-product called olive mill wastewater (OMWW. The uncontrolled disposal of OMWW poses serious environmental problems. The OMWW effluent is rich in several polyphenolic compounds. Liquid-liquid extraction of OMWW using ethyl acetate solvent was used to enrich phenolic compounds under investigation. Total phenolic and flavonoid content and antioxidant activity of the extract were determined. HPLC coupled to photodiode array (PDA detector was used to analyze the main three phenolic compounds of OMWW, namely, hydroxytyrosol, tyrosol, and oleuropein. The antimicrobial activity of the extract was also investigated. Additionally, the OMWW extract was used as natural preservative and antioxidants for olive oil. Results showed that OMWW is very rich in phenolic compounds and has strong antioxidant activity. HPLC analysis showed that the extract contains mainly hydroxytyrosol and tyrosol but no oleuropein. The OMWW extract showed also positive activities as antibacterial (gram positive and gram negative and antifungal as well as activities against yeast. The addition of OMWW extract to olive oil samples has an effect on the stability of olive oil as reflected by its acid value, peroxide value, K232 and K270, and total phenolic content.

  14. Volatile compounds emitted by diverse phytopathogenic microorganisms promote plant growth and flowering through cytokinin action

    Czech Academy of Sciences Publication Activity Database

    Sanchez-Lopez, A.; Baslam, M.; De Diego, N.; Jose Munoz, F.; Bahaji, A.; Almagro, G.; Ricarte-Bermejo, A.; Garcia-Gomez, P.; Li, J.; Humplík, J.F.; Novák, Ondřej; Spíchal, L.; Doležal, Karel; Baroja-Fernandez, E.; Pozueta-Romero, J.

    2016-01-01

    Roč. 39, č. 12 (2016), s. 2592-2608 ISSN 0140-7791 R&D Projects: GA MŠk(CZ) LO1204 Institutional support: RVO:61389030 Keywords : exceptionally high-levels * tandem mass-spectrometry * arabidopsis-thaliana * nitric-oxide * bacterial volatiles * floral transition * anthocyanin biosynthesis * transgenic arabidopsis * liquid-chromatography * organic-compounds * cytokinin * flowering * growth promotion * microbial volatile compounds * photoregulation * photosynthesis * plant-microbe interaction * starch Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 6.173, year: 2016

  15. Global simulation of aromatic volatile organic compounds in the atmosphere

    Science.gov (United States)

    Cabrera Perez, David; Taraborrelli, Domenico; Pozzer, Andrea

    2015-04-01

    Among the large number of chemical compounds in the atmosphere, the organic group plays a key role in the tropospheric chemistry. Specifically the subgroup called aromatics is of great interest. Aromatics are the predominant trace gases in urban areas due to high emissions, primarily by vehicle exhausts and fuel evaporation. They are also present in areas where biofuel is used (i.e residential wood burning). Emissions of aromatic compounds are a substantial fraction of the total emissions of the volatile organic compounds (VOC). Impact of aromatics on human health is very important, as they do not only contribute to the ozone formation in the urban environment, but they are also highly toxic themselves, especially in the case of benzene which is able to trigger a range of illness under long exposure, and of nitro-phenols which cause detrimental for humans and vegetation even at very low concentrations. The aim of this work is to assess the atmospheric impacts of aromatic compounds on the global scale. The main goals are: lifetime and budget estimation, mixing ratios distribution, net effect on ozone production and OH loss for the most emitted aromatic compounds (benzene, toluene, xylenes, ethylbenzene, styrene and trimethylbenzenes). For this purpose, we use the numerical chemistry and climate simulation ECHAM/MESSy Atmospheric Chemistry (EMAC) model to build the global atmospheric budget for the most emitted and predominant aromatic compounds in the atmosphere. A set of emissions was prepared in order to include biomass burning, vegetation and anthropogenic sources of aromatics into the model. A chemical mechanism based on the Master Chemical Mechanism (MCM) was developed to describe the chemical oxidation in the gas phase of these aromatic compounds. MCM have been reduced in terms of number of chemical equation and species in order to make it affordable in a 3D model. Additionally other features have been added, for instance the production of HONO via ortho

  16. Characterization of phenolic compounds and antinociceptive activity of Sempervivum tectorum L. leaf juice.

    Science.gov (United States)

    Alberti, Ágnes; Béni, Szabolcs; Lackó, Erzsébet; Riba, Pál; Al-Khrasani, Mahmoud; Kéry, Ágnes

    2012-11-01

    Sempervivum tectorum L. (houseleek) leaf juice has been known as a traditional herbal remedy. The aim of the present study was the chemical characterization of its phenolic compounds and to develop quantitation methods for its main flavonol glycoside, as well as to evaluate its antinociceptive activity. Lyophilized houseleek leaf juice was studied by HPLC-DAD coupled to electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) to identify flavonol glycosides, hydroxy-benzoic and hydroxy-cinnamic acids. Ten flavonol glycosides and sixteen phenolic acid compounds were identified or tentatively characterized. Structure of the main flavonol compound was identified by nuclear magnetic resonance spectroscopy. Three characteristic kaempferol glycosides were isolated and determined by LC-ESI-MS/MS with external calibration method, using the isolated compounds as standard. The main flavonol glycoside was also determined by HPLC-DAD. Validated HPLC-DAD and LC-ESI-MS/MS methods were developed to quantify kaempferol-3-O-rhamnosyl-glucoside-7-O-rhamnoside and two other kaempferol glycosides. Antinociceptive activity of houseleek leaf juice was investigated by writhing test of mice. Sempervivum extract significantly reduced pain in the mouse writhing test. Copyright © 2012 Elsevier B.V. All rights reserved.

  17. BIOLOGICALLY ACTIVE COMPOUNDS OF ARTEMISIA ANNUA. SESQUITERPENE LACTONES

    Directory of Open Access Journals (Sweden)

    D. A. Konovalov

    2016-01-01

    Full Text Available Artemisia annua is an herblike annual plant which has been used in Chinese folk medicine for more than 2,000 years. In 1970-s sesquiterpene lactones of artemisinin was isolated from the aboveground part of this plant. Today it is the most efficient known natural and synthetic compound for malaria treatment.The purpose of the study was the review of the information from the open sources about the study for sesquiterpene lactones of Artemisia annua referring to its pharmacological activity.Methods. The study was carried out using informational and search engines (PubMed, ScholarGoogle, library databases (eLibrary, Cyberleninca, and the results of our own researches.Results. It was established that apart from the essential oil and phenolic compounds, aboveground part of Artemisia annua, it contains a significant amount of sesquiterpene lactones. Qualitative content and quantitative composition of sesquiterpene lactones varies depending on the ecological and geographic factors, plants growing phase, cultivation technology, drying methods etc. Well-known pharmacological studies of the extracts from Artemisia annua herb with sesquiterpene lactones, as well as individual compounds of this group characterize this type of raw materials as a perspective source for more profound research.Conclusion. Our analysis of the open materials on the sesquiterpene lactones of Artemisia annua, including phytochemical and pharmacological ones, allows characterization of the Artemisia annua herb as a perspective source for new drugs working out.

  18. Antibacterial and Cytotoxic Activity of Extracts and Isolated Compounds from Myrciariaferruginea (Myrtaceae

    Directory of Open Access Journals (Sweden)

    Cinthia Costa de Lima

    2017-01-01

    Full Text Available This study evaluated for the first time the antibacterial activity, cell viability and migration ability on 3T3 murine fibroblast cells of extracts and isolated compounds [lupeol (1, hexamethylcoruleoellagic acid (2 and a mixture of 1 and betulinaldehyde (3] of Myrciaria ferruginea. In antibacterial assays extracts were susceptible only against S. aureus (MIC 500 μg/mL and S. epidermidis (MIC ranging from 7.8 to 500 μg/mL and compounds 1-3have shown no significant activity. In trials for c ell viability, with exception of MeOH-H 2O fraction from leaves (viable cells > 90%, both the crude extract and other fractions showed inhibition of cell growth (viable cells ≤ 80% at 15.625 and 31.25 μg/mL; while the samples from stems, with the exception of CHCl 3 fraction that showed strong cytotoxic effect at the lowest concentration tested (15.625 μg/mL, the other fractions were not cytotoxic. Compounds (1-3 inhibited cell viability in dose dependent manner (15.625 to 500 μg/mL. Mixture containing 1 and 3 showed inhibitions only in concentrations greater than 62.5 μg/mL while compound 2 decreased from the lowest concentration tested. In scratch wound assay, these compoundsnot increased the population of fibroblasts at concentrations less than 62.5 μg/mL.

  19. Several experimental applications of gamma ray spectrometry on the analysis of uranium compounds

    International Nuclear Information System (INIS)

    Korob, Ricardo O.; Blasiyh Nuno, Guillermo A.

    2002-01-01

    Several experimental applications of gamma ray spectrometry on the analysis of uranium compounds and materials containing it are studied. Special attention is devoted to the correlation between experimental spectra and the decay chains of 235 U and 238 U contained in the analyzed samples. The following applications are discussed: enrichment determination without using calibration standards, determination of uranium concentration, intensities of the gamma rays emitted by the nuclides present in the decay chains of study and the activity of such nuclides. Because of its importance, detailed discussion about the former one is shown. In addition, preliminary results regarding the emission probabilities of the most important gamma rays of 234m Pa are also informed. (author)

  20. Antimicrobial activities of some Thai traditional medical longevity formulations from plants and antibacterial compounds from Ficus foveolata.

    Science.gov (United States)

    Meerungrueang, W; Panichayupakaranant, P

    2014-09-01

    Medicinal plants involved in traditional Thai longevity formulations are potential sources of antimicrobial compounds. To evaluate the antimicrobial activities of some extracts from medicinal plants used in traditional Thai longevity formulations against some oral pathogens, including Streptococcus pyogenes, Streptococcus mitis, Streptococcus mutans, and Candida albicans. An extract that possessed the strongest antimicrobial activity was fractionated to isolate and identify the active compounds. Methanol and ethyl acetate extracts of 25 medicinal plants used as Thai longevity formulations were evaluated for their antimicrobial activity using disc diffusion (5 mg/disc) and broth microdilution (1.2-2500 µg/mL) methods. The ethyl acetate extract of Ficus foveolata Wall. (Moraceae) stems that exhibited the strongest antibacterial activity was fractionated to isolate the active compounds by an antibacterial assay-guided isolation process. The ethyl acetate extract of F. foveolata showed the strongest antibacterial activity with minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values of 19.5-39.0 and 39.0-156.2 µg/mL, respectively. On the basis of an antibacterial assay-guided isolation, seven antibacterial compounds, including 2,6-dimethoxy-1,4-benzoquinone (1), syringaldehyde (2), sinapaldehyde (3), coniferaldehyde (4), 3β-hydroxystigmast-5-en-7-one (5), umbelliferone (6), and scopoletin (7), were purified. Among these isolated compounds, 2,6-dimethoxy-1,4-benzoquinone (1) exhibited the strongest antibacterial activities against S. pyogenes, S. mitis, and S. mutans with MIC values of 7.8, 7.8, and 15.6 µg/mL, and MBC values of 7.8, 7.8, and 31.2 µg/mL, respectively. In addition, this is the first report of these antibacterial compounds in the stems of F. foveolata.

  1. Identification of Active Compounds in the Root of Merung (Coptosapelta tomentosa Valeton K. Heyne)

    Science.gov (United States)

    Fitriyana

    2018-04-01

    The roots of Merung (Coptosapelta tomentosa Valeton K. Heyne) are a group of shrubs usually found on the margins of secondary dryland forest. Empirically, local people have been using the roots of Merung for medical treatment. However, some researches show that the plant extract is used as a poisonous material applied on the tip of the arrow (dart). Based on the online literature study, there are less than 5 articles that provide information about the active compound of this root extract. This study aimed to give additional information more deeply about the content of active compound of Merung root extract in three fractions, n-hexane (nonpolar), ethyl acetate (semi polar) and methanol (polar). The extract was then analysed using Gas Chromatography-Mass Spectrometry (GC-MS). GC-MS analysis of root extract in n-hexane showed there were 56 compounds, with the main compound being decanoic acid, methyl ester (peak 5, 10.13%), 11-Octadecenoic acid, methyl ester (peak 15, 10.43%) and 1H-Pyrazole, 3- (4-chlorophenyl) -4, 5-dihydro-1-phenyl (peak 43, 11.25%). Extracts in ethyl acetate fraction obtained 81 compounds. The largest component is Benzoic acid (peak 19, 22.40%), whereas in methanol there are 38 compounds, of which the main component is 2-Furancarboxaldehyde, 5-(hydroxyl methyl) (peak 29, 30.46%).

  2. Solution-processable red-emission organic materials containing triphenylamine and benzothiodiazole units: synthesis and applications in organic light-emitting diodes.

    Science.gov (United States)

    Yang, Yi; Zhou, Yi; He, Qingguo; He, Chang; Yang, Chunhe; Bai, Fenglian; Li, Yongfang

    2009-06-04

    Three solution-processable red-emissive organic materials with a hole-transporting unit triphenylamine (TPA) as the core part and a D-pi-A bipolar structure as the branch part, TPA-BT (single-branched molecule), b-TPA-BT (bibranched molecule), and t-TPA-BT (tribranched molecule), were synthesized by the Heck coupling reaction. Herein, for the D-pi-A push-pull structure, we use TPA as the electron donor, benzothiodiazole (BT) as the electron acceptor, and the vinylene bond as the pi-bridge connecting the TPA and BT units. The compounds exhibit good solubility in common organic solvents, benefited from the three-dimensional spatial configuration of TPA units and the branch structure of the molecules. TPA-BT, b-TPA-BT, and t-TPA-BT show excellent photoluminescent properties with maximum emission peaks at ca. 630 nm. High-performance red-emission organic light-emitting diodes (OLEDs) were fabricated with the active layer spin coated from a solution of these compounds. The OLED based on TPA-BT displayed a low turn-on voltage of 2.0 V, a maximum luminance of 12192 cd/m2, and a maximum current efficiency of 1.66 cd/A, which is among the highest values for the solution-processed red-emission OLEDs. In addition, high-performance white-light-emitting diodes (WLEDs) with maximum luminance around 4400 cd/m2 and maximum current efficiencies above 4.5 cd/A were realized by separately doping the three TPA-BT-containing molecules as red emitter and poly(6,6'-bi-(9,9'-dihexylfluorene)- co-(9,9'-dihexylfluorene-3-thiophene-5'-yl)) as green emitter into blue poly(9,9-dioctylfluorene-2,7-diyl) host material with suitable weight ratios.

  3. N-2-Aryl-1,2,3-Triazoles: A novel class of blue–green emitting fluorophores-synthesis, photophysical properties study and dft computations

    Energy Technology Data Exchange (ETDEWEB)

    Padalkar, Vikas S.; Chemate, Santosh B.; Lanke, Sandip K.; Sekar, Nagaiyan, E-mail: n.sekar@ictmumbai.edu.in

    2015-12-15

    Three novel 2-{2-[4-(N,N-diethylamino)–2–hydroxyphenyl]–1H–benzo[d]imidazol–6–yl} –2H–naphtho [1,2-d] [1,2,3] fluorescent triazole derivatives were synthesized from 2-(5-amino-1H-benzimidazol-2-yl)-5-(N,N-diethylamino)phenol and amino substituted naphthylsulphonic acids. The absorption, emission, quantum yields and dipole moments of these compounds were evaluated in methanol, acetonitrile, N,N-dimethylformamide and dimethylsulfoxide. The compounds 8a and 8c absorb in the near visible region, while compound 8b shows two absorption peaks, short wavelength peak is in the near visible region and long wavelength absorption in the visible region. Compounds are fluorescent in solution and emit in blue and green region. The photophysical properties of the 8a–8c were compared with structural analogs reported till date. The experimental absorption and emission properties were compared with the theoretical data obtained by DFT and TD-DFT computations with TD–B3LYP and CAM–B3LYP functional with 6–31G (d) and 6–311G (d) basis sets. Theoretical results obtained by TD-B3LYP functional are well in line with the experimental results. The compounds are thermally stable up to 300 °C. New compounds were characterized by spectral techniques. - Highlights: • First unique study of blue-emitting ESIPT triazoles. • Improved photophysical properties compared to similar analogues. • Experimental and TDDFT data on photophysical properties. • Dipole moments from solvatochromic data.

  4. New Gold(I) Organometallic Compounds with Biological Activity in Cancer Cells

    NARCIS (Netherlands)

    Bertrand, Benoit; de Almeida, Andreia; van der Burgt, Evelien P. M.; Picquet, Michel; Citta, Anna; Folda, Alessandra; Rigobello, Maria Pia; Le Gendre, Pierre; Bodio, Ewen; Casini, Angela

    N-Heterocyclic carbene gold(I) complexes bearing a fluorescent coumarin ligand were synthesized and characterized by various techniques. The compounds were examined for their antiproliferative effects in normal and tumor cells in vitro; they demonstrated moderate activity and a certain degree of

  5. Biogenic volatile organic compound emissions from vegetation fires.

    Science.gov (United States)

    Ciccioli, Paolo; Centritto, Mauro; Loreto, Francesco

    2014-08-01

    The aim of this paper was to provide an overview of the current state of the art on research into the emission of biogenic volatile organic compounds (BVOCs) from vegetation fires. Significant amounts of VOCs are emitted from vegetation fires, including several reactive compounds, the majority belonging to the isoprenoid family, which rapidly disappear in the plume to yield pollutants such as secondary organic aerosol and ozone. This makes determination of fire-induced BVOC emission difficult, particularly in areas where the ratio between VOCs and anthropogenic NOx is favourable to the production of ozone, such as Mediterranean areas and highly anthropic temperate (and fire-prone) regions of the Earth. Fire emissions affecting relatively pristine areas, such as the Amazon and the African savannah, are representative of emissions of undisturbed plant communities. We also examined expected BVOC emissions at different stages of fire development and combustion, from drying to flaming, and from heatwaves coming into contact with unburned vegetation at the edge of fires. We conclude that forest fires may dramatically change emission factors and the profile of emitted BVOCs, thereby influencing the chemistry and physics of the atmosphere, the physiology of plants and the evolution of plant communities within the ecosystem. © 2014 The Authors. Plant, Cell & Environment published by John Wiley & Sons Ltd.

  6. Bluish-green color emitting Ba2Si3O8:Eu2+ ceramic phosphors for white light-emitting diodes.

    Science.gov (United States)

    Xiao, F; Xue, Y N; Zhang, Q Y

    2009-10-15

    This paper reports on the structural and optical properties of Eu(2+) activated Ba(2)Si(3)O(8) ceramic phosphors synthesized by a sol-gel method. The ceramic phosphors have been characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM) and fluorescence measurements. The structural characterization results suggest that the as-prepared phosphors are of single phase monoclinic Ba(2)Si(3)O(8) with rod-like morphology. A broad excitation band ranging from 300 to 410 nm matches well with the ultraviolet (UV) radiation of light-emitting diodes (LEDs). Upon 380 nm UV light excitation, these phosphors emit bluish-green emission centered at 500 nm with color coordination (x=0.25, y=0.40). All the obtained results indicate that the Ba(2)Si(3)O(8):Eu(2+) ceramic phosphors are promising bluish-green candidates for the phosphor-converted white LEDs.

  7. Polyhydroxybutyrate and phenolic compounds microalgae electrospun nanofibers: A novel nanomaterial with antibacterial activity.

    Science.gov (United States)

    Kuntzler, Suelen Goettems; Almeida, Ana Claudia Araujo de; Costa, Jorge Alberto Vieira; Morais, Michele Greque de

    2018-07-01

    Polymer nanofibers produced by electrospinning are promising for use in food packaging because of their nanometric diameter, which provides a barrier to external conditions above the possible incorporation of the active compounds. The microalga Spirulina sp. LEB 18 synthesizes bioproducts, such as polyhydroxybutyrate (PHB), which is biodegradable and has similar mechanical and thermal properties to polymers of petrochemical origin. Moreover, phenolic compounds of microalgae have antibacterial, antifungal, and antioxidant activities, which is a differential for the development of packaging. The objective of the study was to develop a nanomaterial with antibacterial action from bioproducts of microalgal origin. PHB nanofibers containing phenolic compounds presented average diameter of 810±85nm exhibited hydrophobicity, which gave protection to the food relative to the moisture outside the package. These nanofibers showed inhibition of the growth of Staphylococcus aureus ATCC 25923 with a zone of 7.5±0.4mm. Thermal and mechanical properties have confirmed the potential applicability of this material as food packaging. This new nanomaterial combines a packaging function to protect products and to be biodegradable with the antibacterial activity that prevents the proliferation of microorganisms and ensures the quality and preservation of food. Published by Elsevier B.V.

  8. Cerebroside D, a glycoceramide compound, improves experimental colitis in mice with multiple targets against activated T lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Xue-Feng; Wu, Xing-Xin; Guo, Wen-Jie; Luo, Qiong [State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing 210093 (China); Gu, Yan-Hong [Department of Clinical Oncology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029 (China); Shen, Yan; Tan, Ren-Xiang [State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing 210093 (China); Sun, Yang, E-mail: yangsun@nju.edu.cn [State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing 210093 (China); Xu, Qiang, E-mail: molpharm@163.com [State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing 210093 (China)

    2012-09-15

    In the present paper, we aimed to examine the novel effects of cerebroside D, a glycoceramide compound, on murine experimental colitis. Cerebroside D significantly reduced the weight loss, mortality rate and alleviated the macroscopic and microscopic appearances of colitis induced by dexran sulfate sodium. This compound also decreased the levels of TNF-α, IFN-γ and IL-1β in intestinal tissue of mice with experimental colitis in a concentration-dependent manner, accompanied with markedly increased serum level of IL-10. Cerebroside D inhibited proliferation and induced apoptosis of T cells activated by concanavalin A or anti-CD3 plus anti-CD28 antibodies. The compound did not show an effect on naive lymphocytes but prevented cells from entering S phase and G2/M phase during T cells activation. Moreover, the treatment of cerebroside D led to apoptosis of activated T cells with the cleavage of caspase 3, 9, 12 and PARP. These results showed multiple effects of cerebroside D against activated T cells for a novel approach to treatment of colonic inflammation. Highlights: ► Cerebroside D, a glycoceramide compound, alleviated DSS induced colitis. ► The mechanism of the compound involved multiple effects against activated T cells. ► It regulated cytokine profiles in mice with experimental colitis. ► It prevented T cells from entering S and G2/M phases during activation. ► It led to apoptosis of activated T cells with the cleavage of caspases and PARP.

  9. Cerebroside D, a glycoceramide compound, improves experimental colitis in mice with multiple targets against activated T lymphocytes

    International Nuclear Information System (INIS)

    Wu, Xue-Feng; Wu, Xing-Xin; Guo, Wen-Jie; Luo, Qiong; Gu, Yan-Hong; Shen, Yan; Tan, Ren-Xiang; Sun, Yang; Xu, Qiang

    2012-01-01

    In the present paper, we aimed to examine the novel effects of cerebroside D, a glycoceramide compound, on murine experimental colitis. Cerebroside D significantly reduced the weight loss, mortality rate and alleviated the macroscopic and microscopic appearances of colitis induced by dexran sulfate sodium. This compound also decreased the levels of TNF-α, IFN-γ and IL-1β in intestinal tissue of mice with experimental colitis in a concentration-dependent manner, accompanied with markedly increased serum level of IL-10. Cerebroside D inhibited proliferation and induced apoptosis of T cells activated by concanavalin A or anti-CD3 plus anti-CD28 antibodies. The compound did not show an effect on naive lymphocytes but prevented cells from entering S phase and G2/M phase during T cells activation. Moreover, the treatment of cerebroside D led to apoptosis of activated T cells with the cleavage of caspase 3, 9, 12 and PARP. These results showed multiple effects of cerebroside D against activated T cells for a novel approach to treatment of colonic inflammation. Highlights: ► Cerebroside D, a glycoceramide compound, alleviated DSS induced colitis. ► The mechanism of the compound involved multiple effects against activated T cells. ► It regulated cytokine profiles in mice with experimental colitis. ► It prevented T cells from entering S and G2/M phases during activation. ► It led to apoptosis of activated T cells with the cleavage of caspases and PARP.

  10. A screening method for cardiovascular active compounds in marine algae.

    Science.gov (United States)

    Agatonovic-Kustrin, S; Kustrin, E; Angove, M J; Morton, D W

    2018-05-18

    The interaction of bioactive compounds from ethanolic extracts of selected marine algae samples, separated on chromatographic plates, with nitric/nitrous acid was investigated. The nature of bioactive compounds in the marine algae extracts was characterised using UV absorption spectra before and after reaction with diluted nitric acid, and from the characteristic colour reaction after derivatization with anisaldehyde. It was found that diterpenes from Dictyota dichotoma, an edible brown algae, and sterols from green algae Caulerpa brachypus, bind nitric oxide and may act as a nitric oxide carrier. Although the carotenoid fucoxanthin, found in all brown marine algae also binds nitric oxide, the bonds between nitrogen and the fucoxanthin molecule are much stronger. Further studies are required to evaluate the effects of diterpenes from Dictyota dichotoma and sterols from green algae Caulerpa brachypus to see if they have beneficial cardiovascular effects. The method reported here should prove useful in screening large numbers of algae species for compounds with cardiovascular activity. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. Novel green-emitting Na2CaPO4F:Eu2+ phosphors for near-ultraviolet white light-emitting diodes

    International Nuclear Information System (INIS)

    Huang, Chien-Hao; Chen, Yen-Chi; Kuo, Te-Wen; Chen, Teng-Ming

    2011-01-01

    In this study, green-emitting Na 2 CaPO 4 F:Eu 2+ phosphors were synthesized by solid-state reactions. The excitation spectra of the phosphors showed a broad hump between 250 and 450 nm; the spectra match well with the near-ultraviolet (NUV) emission spectra of light-emitting diodes (LEDs). The emission spectrum showed an intense broad emission band centered at 506 nm. White LEDs were fabricated by integrating a 390 nm NUV chip comprising blue-emitting BaMgAl 10 O 17 :Eu 2+ , green-emitting Na 2 CaPO 4 F:0.02 Eu 2+ , and red-emitting CaAlSiN 3 :Eu 2+ phosphors into a single package; the white LEDs exhibited white light with a correlated color temperature of 5540 K, a color-rendering index of 90.75, and color coordinates (0.332, 0.365) close to those of ideal white light. - Highlights: → Novel green-emitting Na 2 CaPO 4 F:Eu 2+ phosphors were synthesized by solid-state reactions in this research. → White LEDs were fabricated by integrating a 390 nm NUV chip comprising blue-emitting BaMgAl 10 O 17 :Eu 2+ , green-emitting Na 2 CaPO 4 F:0.02Eu 2+ , and red-emitting CaAlSiN 3 :Eu 2+ phosphors into a single package. → The white LEDs exhibited white light with a correlated color temperature of 5540 K, a color-rendering index of 90.75, and color coordinates (0.332, 0.365) close to those of ideal white light.

  12. Antibacterial activity of sphagnum acid and other phenolic compounds found in Sphagnum papillosum against food-borne bacteria.

    Science.gov (United States)

    Mellegård, H; Stalheim, T; Hormazabal, V; Granum, P E; Hardy, S P

    2009-07-01

    To identify the phenolic compounds in the leaves of Sphagnum papillosum and examine their antibacterial activity at pH appropriate for the undissociated forms. Bacterial counts of overnight cultures showed that whilst growth of Staphylococcus aureus 50084 was impaired in the presence of milled leaves, the phenol-free fraction of holocellulose of S. papillosum had no bacteriostatic effect. Liquid chromatography-mass spectrometry analysis of an acetone-methanol extract of the leaves detected eight phenolic compounds. Antibacterial activity of the four dominating phenols specific to Sphagnum leaves, when assessed in vitro as minimal inhibitory concentrations (MICs), were generally >2.5 mg ml(-1). MIC values of the Sphagnum-specific compound 'sphagnum acid' [p-hydroxy-beta-(carboxymethyl)-cinnamic acid] were >5 mg ml(-1). No synergistic or antagonistic effects of the four dominating phenols were detected in plate assays. Sphagnum-derived phenolics exhibit antibacterial activity in vitro only at concentrations far in excess of those found in the leaves. We have both identified the phenolic compounds in S. papillosum and assessed their antibacterial activity. Our data indicate that phenolic compounds in isolation are not potent antibacterial agents and we question their potency against food-borne pathogens.

  13. Simple single-emitting layer hybrid white organic light emitting with high color stability

    Science.gov (United States)

    Nguyen, C.; Lu, Z. H.

    2017-10-01

    Simultaneously achieving a high efficiency and color quality at luminance levels required for solid-state lighting has been difficult for white organic light emitting diodes (OLEDs). Single-emitting layer (SEL) white OLEDs, in particular, exhibit a significant tradeoff between efficiency and color stability. Furthermore, despite the simplicity of SEL white OLEDs being its main advantage, the reported device structures are often complicated by the use of multiple blocking layers. In this paper, we report a highly simplified three-layered white OLED that achieves a low turn-on voltage of 2.7 V, an external quantum efficiency of 18.9% and power efficiency of 30 lm/W at 1000 cd/cm2. This simple white OLED also shows good color quality with a color rendering index of 75, CIE coordinates (0.42, 0.46), and little color shifting at high luminance. The device consists of a SEL sandwiched between a hole transport layer and an electron transport layer. The SEL comprises a thermally activated delayer fluorescent molecule having dual functions as a blue emitter and as a host for other lower energy emitters. The improved color stability and efficiency in such a simple device structure is explained as due to the elimination of significant energy barriers at various organic-organic interfaces in the traditional devices having multiple blocking layers.

  14. A herbicide structure-activity analysis of the antimalarial lead compound MMV007978 against Arabidopsis thaliana.

    Science.gov (United States)

    Corral, Maxime G; Leroux, Julie; Tresch, Stefan; Newton, Trevor; Stubbs, Keith A; Mylne, Joshua S

    2018-07-01

    To fight herbicide-resistant weeds, new herbicides are needed; particularly ones with new modes of action. Building on the revelation that many antimalarial drugs are herbicidal, here we focus on the Medicines for Malaria Venture antimalarial lead compound MMV007978 that has herbicidal activity against the model plant Arabidopsis thaliana. Twenty-two variations of the lead compound thiophenyl motif revealed that change was tolerated provided ring size and charge were retained. MMV007978 was active against select monocot and dicot weeds, and physiological profiling indicated that its mode of action is related to germination and cell division. Of interest is the fact that the compound has a profile that is currently not found among known herbicides. We demonstrate that the antimalarial compound MMV007978 is also herbicidal and that exploiting lead compounds that are often understudied could lead to the identification of interesting herbicidal scaffolds. Further structural investigation of MMV007978 could provide improved herbicidal chemistries with a potential new mode of action. © 2018 Society of Chemical Industry. © 2018 Society of Chemical Industry.

  15. Bioassay Guided Isolation of Active Compounds from Alchemilla barbatiflora Juz.

    Directory of Open Access Journals (Sweden)

    Gülin Renda

    2018-01-01

    Full Text Available The aerial parts of Alchemilla L. species (Rosaceae are used internally as diuretic, laxative, tonic and externally for wound healing in Turkish folk medicine. Antioxidant effects of the extracts, fractions and isolated compounds from the aerial parts of A. barbatiflora Juz. were investigated with following methods: 1,1-diphenyl-2-picryl-hydrazyl (DPPH, and superoxide radical scavenging (SOD, phosphomolibdenum-reducing antioxidant power (PRAP, ferric-reducing antioxidant power (FRAP assays. In addition, tyrosinase, α-glucosidase and acetylcholinesterase inhibition activities of samples were analyzed. The methanol extract from the aerial parts of plant was consecutively fractionated into four subextracts; n-hexane, chloroform, and remaining water extracts. Further studies were carried out on the most active water subextract and the fractions obtained from water subextract with column chromatography. Phytochemical studies on active fractions of the water subextract led to the isolation of seven metabolites including catechin (1 and a catechin dimer; procyanidin B3 (2, a flavonol glucuronide; quercetin-3-O- β-D-glucuronic acid (miquelianin (3 with flavonoid glycosides; quercetin-3-O- β-D-galactoside (hyperoside (4, quercetin-3-O- β-D-arabinoside (guaiaverin (5, kaempferol-3-O-β-D-xylopyranoside (6 and kaempferol-3-O -(6″-coumaroyl-β-D-glycoside (tiliroside (7. Their structures were elucidated by spectral techniques (1D and 2D NMR. The experimental data verified that procyanidin B3 displayed remarkable enzyme inhibitory activity among the whole isolated compounds.

  16. Superior bactericidal activity of N-bromine compounds compared to their N-chlorine analogues can be reversed under protein load.

    Science.gov (United States)

    Gottardi, W; Klotz, S; Nagl, M

    2014-06-01

    To investigate and compare the bactericidal activity (BA) of active bromine and chlorine compounds in the absence and presence of protein load. Quantitative killing tests against Escherichia coli and Staphylococcus aureus were performed both in the absence and in the presence of peptone with pairs of isosteric active chlorine and bromine compounds: hypochlorous and hypobromous acid (HOCl and HOBr), dichloro- and dibromoisocyanuric acid, chlorantine and bromantine (1,3-dibromo- and 1,3 dichloro-5,5-dimethylhydantoine), chloramine T and bromamine T (N-chloro- and N-bromo-4-methylbenzenesulphonamide sodium), and N-chloro- and N-bromotaurine sodium. To classify the bactericidal activities on a quantitative basis, an empirical coefficient named specific bactericidal activity (SBA), founded on the parameters of killing curves, was defined: SBA= mean log reductions/(mean exposure times x concentration) [mmol 1(-1) min (-1)]. In the absence of peptone, tests with washed micro-organisms revealed a throughout higher BA of bromine compounds with only slight differences between single substances. This was in contrast to chlorine compounds, whose killing times differed by a factor of more than four decimal powers. As a consequence, also the isosteric pairs showed according differences. In the presence of peptone, however, bromine compounds showed an increased loss of BA, which partly caused a reversal of efficacy within isosteric pairs. In medical practice, weakly oxidizing active chlorine compounds like chloramines have the highest potential as topical anti-infectives in the presence of proteinaceous material (mucous membranes, open wounds). Active bromine compounds, on the other hand, have their chance at insensitive body regions with low organic matter, for example skin surfaces. The expected protein load is one of the most important parameters for selection of a suited active halogen compound. © 2014 The Society for Applied Microbiology.

  17. Influence of Technological Processes on Biologically Active Compounds of Produced Grapes Juices

    Czech Academy of Sciences Publication Activity Database

    Tříska, Jan; Balík, J.; Strohalm, J.; Novotná, P.; Vrchotová, Naděžda; Lefnerová, D.; Landfeld, A.; Híc, P.; Tománková, E.; Veverka, J.; Houška, M.

    2016-01-01

    Roč. 9, č. 3 (2016), s. 421-429 ISSN 1935-5130 R&D Projects: GA MŠk(CZ) LO1415; GA MZe QJ1210258; GA MZe QI91B094 Institutional support: RVO:67179843 Keywords : Grapevine juices * Thermomaceration * Biologically active compounds * Antioxidative capacity * Total polyphenols * Antimutagenic activity Subject RIV: GM - Food Processing Impact factor: 2.576, year: 2016

  18. Activity-Guided Isolation of Antioxidant Compounds from Rhizophora apiculata

    Directory of Open Access Journals (Sweden)

    Hongbin Xiao

    2012-09-01

    Full Text Available Rhizophora apiculata (R. apiculata contains an abundance of biologically active compounds due its special salt-tolerant living surroundings. In this study, the total phenolic content and antioxidant activities of various extract and fractions of stem of R. apiculata were investigated. Results indicated that butanol fraction possesses the highest total phenolic content (181.84 mg/g GAE/g dry extract with strongest antioxidant abilities. Following in vitro antioxidant activity-guided phytochemical separation procedures, lyoniresinol-3α-O-β-arabinopyranoside (1, lyoniresinol-3α-O-β-rhamnoside (2, and afzelechin-3-O-L-rhamno-pyranoside (3 were separated from the butanol fraction. These compounds showed more noticeable antioxidant activity than a BHT standard in the DPPH, ABTS and hydroxyl radical scavenging assays. HPLC analysis results showed that among different plant parts, the highest content of 13 was located in the bark (0.068%, 0.066% and 0.011%, respectively. The results imply that the R. apiculata might be a potential source of natural antioxidants and 13 are antioxidant ingredients in R. apiculata.

  19. Beyond the network of plants volatile organic compounds

    OpenAIRE

    Vivaldo, Gianna; Masi, Elisa; Taiti, Cosimo; Caldarelli, Guido; Mancuso, Stefano

    2017-01-01

    Plants emission of volatile organic compounds (VOCs) is involved in a wide class of ecological functions, as VOCs play a crucial role in plants interactions with biotic and abiotic factors. Accordingly, they vary widely across species and underpin differences in ecological strategy. In this paper, VOCs spontaneously emitted by 109 plant species (belonging to 56 different families) have been qualitatively and quantitatively analysed in order to classify plants species. By using bipartite netwo...

  20. Fabrication of a white-light-emitting organic LED adopting the two-wavelength method by using new DPVBi derivatives and an analysis of its characteristics

    International Nuclear Information System (INIS)

    Oh, Hwan-Sool; Cho, Jae-Young; Yoon, Seok-Beom; Kang, Myung-Koo

    2004-01-01

    The white-light emission of the two-wavelength method was represented by the processes of compounding new DPVBi derivatives, methyl-DPVT and nitro-DPVT, from the blue-emitting material DPVBi, after which blue light was emitted from nitro-DPVT and orange light was emitted by doping methyl-DPVT as a host material with Rubrene as a guest material. The basic structure of the fabricated organic white-light-emitting organic light-emitting device (OLED) was glass/ITO/NPB(150 A)/nitro-DPVT(100 A)/methyl-DPVT:Rubrene [2.0 wt%]/BCP(70 A)/Alq 3 (150 A)/Al(600 A).We evaluated the characteristics by varying the thickness of the methyl-DPVT:Rubrene layer from 100 A to 90 A to 80 A to 60 A and obtained nearly-pure white light in the Commission Internationale de l'Eclairage (CIE) coordinates (0.3175, 0.3338) in the case where the methyl-DPVT:Rubrene layer was 60-A thick. It turned out that the device remained stable against voltage changes, the turn-on voltage was 3.5 V, the light-emitting turn-on voltage was 4 V, and the external quantum efficiency was more than 0.5 % for all injection currents.

  1. Synthesis, crystal structure and biological activity of a novel 1,2,3-thidiazole compound

    International Nuclear Information System (INIS)

    Ke, W.

    2013-01-01

    A new 1,2,3-thiadiazole compound was synthesized and characterized by 1H NMR, MS and HRMS. The crystal structure of the title compound (C/sub 12/H/sub 11/ClN/sub 2/O/sub 4/S/sub 2/, Mr = 346.80) has been determined by single-crystal X-ray diffraction. The crystal is of triclinic, space group P-1 with a = 8.4425(17) A, b = 8.9801(18) A, c = 9.859(2) A, alpha = 84.36(3) degree, beta = 86.71(3)degree, lambda = 83.25(3) degree, V = 737.9(3)A3, Z 2, F(000) = 356, Dc = 1.561 g/cm/sup 3/, mu = 0.557 mm-1, the final R1 0.0380 and wR2 = 0.0982 for 2160 observed reflections with I > 2sigma(I). A total of 12585 reflections were collected, of which 2601 were independent (Rint 0.0364). The herbicidal activity of title compound was determined, the results showed the title compound displayed excellent herbicidal activity against Brassica campestris. (author)

  2. Controlled light emission from white organic light-emitting devices with a single blue-emitting host and multiple fluorescent dopants

    International Nuclear Information System (INIS)

    Chin, Byung Doo; Kim, Jai Kyeong; Park, O Ok

    2007-01-01

    In this work, we fabricated white organic light-emitting devices (WOLEDs) containing a layered light-emitting region composed of a single blue-emitting host and different fluorescent dopant materials. The effects of varying the dye-doping ratio and emitting layer thickness on the efficiency, lifetime, spectral voltage-dependence and white balance were investigated for devices with a blue/orange stacked layer structure. Addition of a blue host layer doped with a green-emitting dopant, to give a blue/green/orange emitter, resulted in a broadband white spectrum without the need for a charge-blocking interlayer. The composition of blue, green and orange dopants in the host and the thickness of each emitting layer were optimized, resulting in a device efficiency of 9-11 cd A -1 even at a high brightness of 10 000 cd m -2 (achieved at a bias voltage of less than 9 V) with an emission spectrum suitable for lighting applications

  3. Antileishmanial, antimalarial and antimicrobial activities of the extract and isolated compounds from Austroplenckia populnea (Celastraceae).

    Science.gov (United States)

    Andrade, Sérgio F; da Silva Filho, Ademar A; de O Resende, Dimas; Silva, Márcio L A; Cunha, Wilson R; Nanayakkara, N P Dhammika; Bastos, Jairo Kenupp

    2008-01-01

    Austroplenckia populnea (Celastraceae), known as "marmelinho do campo", is used in Brazilian folk medicine as antimicrobial, anti-inflammatory, and antitumoural agent. The aim of the present work was to evaluate the antimicrobial, antileishmanial and antimalarial activities of the crude hydroalcoholic extract of A. populnea (CHE) and some of its isolated compounds. The phytochemical study of the CHE was carried out affording the isolation of methyl populnoate (1), populnoic acid (2), and stigmast-5-en-3-O-beta-(D-glucopyranoside) (3). This is the first time that the presence of compound 3 in A. populnea is reported. The results showed that the CHE presents antifungal and antibacterial activities, especially against Candida glabrata and Candida albicans, for which the CHE showed IC50 values of 0.7 microg mL(-1) and 5.5 microg mL(-1), respectively, while amphotericin B showed an IC50 value of 0.1 microg mL(-1) against both microorganisms. Compounds 1-3 were inactive against all tested microorganisms. In the antileishmanial activity test against Leishmania donovani, the CHE showed an IC50 value of 52 microg mL(-1), while compounds 2 and 3 displayed an IC50 value of 18 microg mL(-1) In the antimalarial assay against Plasmodium falciparum (D6 and W2 clones), it was observed that all evaluated samples were inactive. In order to compare the effect on the parasites with the toxicity to mammalian cells, the cytotoxicity activity of the isolated compounds was evaluated against Vero cells, showing that all evaluated samples exhibited no cytotoxicity at the maximum dose tested.

  4. A SAR and QSAR Study of New Artemisinin Compounds with Antimalarial Activity

    Directory of Open Access Journals (Sweden)

    Cleydson Breno R. Santos

    2013-12-01

    Full Text Available The Hartree-Fock method and the 6-31G** basis set were employed to calculate the molecular properties of artemisinin and 20 derivatives with antimalarial activity. Maps of molecular electrostatic potential (MEPs and molecular docking were used to investigate the interaction between ligands and the receptor (heme. Principal component analysis and hierarchical cluster analysis were employed to select the most important descriptors related to activity. The correlation between biological activity and molecular properties was obtained using the partial least squares and principal component regression methods. The regression PLS and PCR models built in this study were also used to predict the antimalarial activity of 30 new artemisinin compounds with unknown activity. The models obtained showed not only statistical significance but also predictive ability. The significant molecular descriptors related to the compounds with antimalarial activity were the hydration energy (HE, the charge on the O11 oxygen atom (QO11, the torsion angle O1-O2-Fe-N2 (D2 and the maximum rate of R/Sanderson Electronegativity (RTe+. These variables led to a physical and structural explanation of the molecular properties that should be selected for when designing new ligands to be used as antimalarial agents.

  5. Hybrid white organic light-emitting devices consisting of a non-doped thermally activated delayed fluorescent emitter and an ultrathin phosphorescent emitter

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Juan [State Key Laboratory of Electronic Thin Film and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China, Chengdu 610054 (China); School of Chemistry, Sun Yat-sen University, Guangzhou 510275 (China); Wang, Zijun; Wang, Run [State Key Laboratory of Electronic Thin Film and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China, Chengdu 610054 (China); Chi, Zhenguo, E-mail: chizhg@mail.sysu.edu.cn [School of Chemistry, Sun Yat-sen University, Guangzhou 510275 (China); Yu, Junsheng, E-mail: jsyu@uestc.edu.cn [State Key Laboratory of Electronic Thin Film and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China, Chengdu 610054 (China)

    2017-04-15

    Hybrid white organic light-emitting devices (OLEDs) are fabricated by employing non-doped emitting layers (EMLs), which are consisted of a blue thermally activated delayed fluorescent (TADF) emitter 9,9-dimethyl-9,10-dihydroacridine-diphenylsulfone (DMAC-DPS) and an ultrathin yellow iridium complex bis[2-(4-tertbutylphenyl)benzothiazolato-N,C{sup 2′}] iridium (acetylacetonate) [(tbt){sub 2}Ir(acac)]. With thickness optimization of DMAC-DPS, a white OLED achieves maximum current efficiency, power efficiency and external quantum efficiency of 34.9 cd/A, 29.2 lm/W and 11.4%, respectively, as well as warm white emission with relatively stable electroluminescence spectra. The results suggest that, bipolar charge carrier transport property and concentration independent property of DMAC-DPS, charge carrier trapping effect of the ultrathin (tbt){sub 2}Ir(acac), and balanced self-emission process and energy transfer process between DMAC-DPS and (tbt){sub 2}Ir(acac), contribute to high device performance.

  6. Therapeutic Uses and Pharmacological Properties of Garlic, Shallot, and Their Biologically Active Compounds

    Science.gov (United States)

    Mikaili, Peyman; Maadirad, Surush; Moloudizargari, Milad; Aghajanshakeri, Shahin; Sarahroodi, Shadi

    2013-01-01

    Objective(s): Garlic (Allium sativum L. family Liliaceae) is well known in Iran and its leaves, flowers, and cloves have been used in traditional medicine for a long time. Research in recent decades has shown widespread pharmacological effects of A. sativum and its organosulfur compounds especially Allicin. Studies carried out on the chemical composition of the plant show that the most important constituents of this plant are organosulfur compounds such as allicin, diallyl disulphide, S-allylcysteine, and diallyl trisulfide. Allicin represents one of the most studied among these naturally occurring compounds. In addition to A. sativum, these compounds are also present in A. hirtifolium (shallot) and have been used to treat various diseases. This article reviews the pharmacological effects and traditional uses of A. sativum, A. hirtifolium, and their active constituents to show whether or not they can be further used as potential natural sources for the development of novel drugs. Materials and Methods: For this purpose, the authors went through a vast number of sources and articles and all needed data was gathered. The findings were reviewed and classified on the basis of relevance to the topic and a summary of all effects were reported as tables. Conclusion: Garlic and shallots are safe and rich sources of biologically active compounds with low toxicity. Further studies are needed to confirm the safety and quality of the plants to be used by clinicians as therapeutic agents. PMID:24379960

  7. Tuning the colour of white polymer light emitting diodes

    NARCIS (Netherlands)

    Kok, M.M. de; Sarfert, W.; Paetzold, R.

    2010-01-01

    Colour tuning of white polymer light emitting diode (LED) light sources can be attained by various methods at various stages in the production process of the lamps and/or by the design of the active material incorporated in the LEDs. In this contribution we will describe the methods and discuss the

  8. Punica granatum peel extracts: HPLC fractionation and LC MS analysis to quest compounds having activity against multidrug resistant bacteria.

    Science.gov (United States)

    Khan, Ilyas; Rahman, Hazir; Abd El-Salam, Nasser M; Tawab, Abdul; Hussain, Anwar; Khan, Taj Ali; Khan, Usman Ali; Qasim, Muhammad; Adnan, Muhammad; Azizullah, Azizullah; Murad, Waheed; Jalal, Abdullah; Muhammad, Noor; Ullah, Riaz

    2017-05-03

    Medicinal plants are rich source of traditional herbal medicine around the globe. Most of the plant's therapeutic properties are due to the presence of secondary bioactive compounds. The present study analyzed the High Pressure Liquid Chromatography (HPLC) fractions of Puncia granatum (peel) extracts (aqueous, chloroform, ethanol and hexane) against multidrug resistant bacterial pathogens (Acinetobacter baumannii, Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus). All the fractions having antibacterial activity was processed for bioactive compounds identification using LC MS/MS analysis. Among total HPLC fractions (n = 30), 4 HPLC fractions of P. granatum (peel) showed potential activity against MDR pathogens. Fraction 1 (F1) and fraction 4 (F4) collected from aqueous extract showed maximum activity against P. aeruginosa. Fraction 2 (F2) of hexane showed antibacterial activity against three pathogens, while ethanol F4 exhibited antibacterial activity against A. baumannii. The active fractions were processed for LC MS/MS analysis to identify bioactive compounds. Valoneic acid dilactone (aqueous F1 and F4), Hexoside (ethanol F4) and Coumaric acid (hexane F2) were identified as bioactive compounds in HPLC fractions. Puncia granatum peel extracts HPLC fractions exhibited potential inhibitory activity against MDR bacterial human pathogens. Several bioactive compounds were identified from the HPLC fractions. Further characterization of these compounds may be helpful to conclude it as therapeutic lead molecules against MDR pathogens.

  9. Characterization of key aroma-active compounds in lychee (Litchi chinensis Sonn.).

    Science.gov (United States)

    Feng, Shi; Huang, Mingyang; Crane, Jonathan Henry; Wang, Yu

    2018-04-01

    Volatile compounds in 'Sweetheart' lychee were examined using gas chromatography-olfactometry/mass spectrometry (GC-O/MS). Solvent assisted flavor evaporation (SAFE) technique was used to identify the aroma-active compounds in lychee. Further characterization of the most important odorants in 'Sweetheart' lychee was achieved using aroma extract dilution analysis (AEDA). Thirty-one key aroma-active odorants were identified in the flavor dilution (FD) factor range of 2-1024. Methional (cooked potato) and geraniol (sweet, floral) exhibited the highest FD factors of 1024 and 512, respectively, these were followed by furaneol (sweet, caramel), nerol (floral, sweet), dimethyl trisulfide (DMTS) (preserved vegetable, sulfury), linalool (floral), (E,Z)-2,6 nonadienal (cucumber) and nerolidol (metalic, sesame oil). Furthermore, the flavor profile of 'Sweetheart' lychee was described by sensory analysis. Floral, tropical fruit, peach/apricot and honey were scored with relatively high scores for each aroma attribute. The sweetness rating was the highest score among all the attributes. Copyright © 2017. Published by Elsevier B.V.

  10. Evaluation of Antibacterial Activity and Total Phenol Compounds of Punica granatum Hydro-Alcoholic Extract

    Directory of Open Access Journals (Sweden)

    Elahe Ahmadi

    2016-12-01

    Full Text Available Background & Objectives: Punica granatum is a non-productive form of a plant and is used for the treatment of diseases in traditional medicine. In this study, we evaluate the antibacterial activity and the total phenol compounds of Punica granatum. Materials & Methods: Disk and well diffusion methods and MIC were used to evaluate the antibacterial activity of hydro-alcoholic extract on S. aureus and E. coli compared to standard commercial antibiotic disks. Measurement of phenol compounds were performed by Seevers and Daly colorimetric methods (Folin-ciocalteu indicator. Results: 35 and 29 mm inhibition zones in S. aureus and 22 and 17 mm inhibition zones in E. coli were shown by disk and well diffusion method, respectively. Also, 7.8 mg/ml concentration of extract showed the MIC points for two bacteria. Phenol compound of extract was 233.15±5.1 mg/g of extraction. Conclusion: Antibacterial effect of Punica granatum compared to antibiotics indicates the strong activity against examined bacteria. Extensive antibacterial study of Punica granatum is suggested.

  11. Novel UV-emitting single crystalline film phosphors grown by LPE method

    International Nuclear Information System (INIS)

    Zorenko, Y.; Gorbenko, V.; Savchyn, V.; Voznyak, T.; Nikl, M.; Mares, J.A.; Winnacker, A.

    2010-01-01

    This work reports the development of new types of UV-emitting phosphors based on single crystalline films (SCF) of aluminum garnet and perovskite compounds grown by the liquid phase epitaxy method. We consider peculiarities of the growth and the luminescent and scintillation properties of the following four types of UV SCF phosphors: i) Ce-doped SCF of Y-Lu-Al-perovskites with the Ce 3+ emission in the 300-450 nm range of the decay time of 16-17 ns; ii) Pr-doped SCF of Y-Lu-Al garnets and perovskites with the Pr 3+ emission in the 300-400 nm and 235-330 nm ranges with the decay time of 13-19 and 7-8 ns, respectively; iii) La 3+ or Sc 3+ doped SCF of Y-Lu-Al-garnets, emitting in the 280-400 nm range due to formation of the La Y,Lu , Sc Y,Lu and Sc Al centers with decay time of the order of several hundreds of nanoseconds; iv) Bi 3+ doped SCF of garnets with Bi 3+ emission in 275-350 nm with decay time of about 1.9 μs.

  12. Volatile compounds of Lamiaceae exhibit a synergistic antibacterial activity with streptomycin

    Directory of Open Access Journals (Sweden)

    Sthéfane G. Araújo

    2014-12-01

    Full Text Available Bacterial infections cause thousands of deaths in the world every year. In most cases, infections are more serious because the patient is already weakened, and often, the bacteria are already resistant to the antibiotics used. Counterparting this negative scenario, the interest in medicinal plants as an alternative to the synthetic antimicrobial drugs is blossoming worldwide. In the present work, we identified the volatile compounds of ethanol extracts of Melissa officinalis, Mentha sp., Ocimum basilicum, Plectranthus barbatus, and Rosmarinus officinalis by gas chromatography/mass spectrometry (GC/MS. Also was evaluated antimicrobial activity of ethanol extracts against 6 bacteria of clinical interest, and was tested the interaction of these extracts with a commercial antibiotic streptomycin. Phytol was a compound identified in all extracts by GC/MS, being majoritary component in Plectranthus barbatus and Rosmarinus officinalis. The Gram-positive bacteria were more sensitive to ethanol extracts, and Plectranthus barbatus and Rosmarinus officinalis were the most active extracts. Ethanol extracts exhibited a synergetic effect with streptomycin. These results encourage additional studies, in order to evaluate the possibilities of using ethanol extracts of Lamiaceae family as natural source for antibacterial activity.

  13. Phenolic compounds and antioxidant activity in red fruits produced in organic farming

    Directory of Open Access Journals (Sweden)

    Susana M. A. Soutinho

    2014-01-01

    Full Text Available In this work were studied three red fruits (raspberry, gooseberry and blueberry produced in organic mode, to evaluate the variations in the content of phenolic compounds and antioxidant capacity along maturation. The phenols were extracted from the fruits with two solvents (methanol and acetone and were quantified by the Folin-Ciocalteu method. The antioxidant activity was determined with two methods (HPPH and ABTS. Furthermore, HPLC was used to identify and quantify some phenolic compounds present in the fruits analyzed. The results showed that the total phenolic compounds in all fruits decreased along maturation, either in the methanol or acetone extracts (23 % and 20 % reduction, on average, for methanol and acetone extracts, respectively, although in methanol extracts the levels of phenolic compounds were always higher (0.54 and 0.21 mg GAE/g. The blueberry showed higher level of total phenolics in methanol extract (average 0.67 mg GAE/g, while in the acetone extract it was gooseberry (average 0.31 mg GAE/g. At the end of maturation, all fruits studied had similar values of antioxidant capacity as determined by DPPH method (0.52 mmol Trolox/g. For the ABTS method, blueberries showed higher values of antioxidant activity (6.01 mmol Trolox/g against 3.01 and 2.66 mmol Trolox/g, for raspberry and gooseberry, respectively. Furthermore, the HPLC analysis allowed to identify monomeric anthocyanins and phenolic acids in the three fruits studied.

  14. A network-based multi-target computational estimation scheme for anticoagulant activities of compounds.

    Directory of Open Access Journals (Sweden)

    Qian Li

    Full Text Available BACKGROUND: Traditional virtual screening method pays more attention on predicted binding affinity between drug molecule and target related to a certain disease instead of phenotypic data of drug molecule against disease system, as is often less effective on discovery of the drug which is used to treat many types of complex diseases. Virtual screening against a complex disease by general network estimation has become feasible with the development of network biology and system biology. More effective methods of computational estimation for the whole efficacy of a compound in a complex disease system are needed, given the distinct weightiness of the different target in a biological process and the standpoint that partial inhibition of several targets can be more efficient than the complete inhibition of a single target. METHODOLOGY: We developed a novel approach by integrating the affinity predictions from multi-target docking studies with biological network efficiency analysis to estimate the anticoagulant activities of compounds. From results of network efficiency calculation for human clotting cascade, factor Xa and thrombin were identified as the two most fragile enzymes, while the catalytic reaction mediated by complex IXa:VIIIa and the formation of the complex VIIIa:IXa were recognized as the two most fragile biological matter in the human clotting cascade system. Furthermore, the method which combined network efficiency with molecular docking scores was applied to estimate the anticoagulant activities of a serial of argatroban intermediates and eight natural products respectively. The better correlation (r = 0.671 between the experimental data and the decrease of the network deficiency suggests that the approach could be a promising computational systems biology tool to aid identification of anticoagulant activities of compounds in drug discovery. CONCLUSIONS: This article proposes a network-based multi-target computational estimation

  15. A network-based multi-target computational estimation scheme for anticoagulant activities of compounds.

    Science.gov (United States)

    Li, Qian; Li, Xudong; Li, Canghai; Chen, Lirong; Song, Jun; Tang, Yalin; Xu, Xiaojie

    2011-03-22

    Traditional virtual screening method pays more attention on predicted binding affinity between drug molecule and target related to a certain disease instead of phenotypic data of drug molecule against disease system, as is often less effective on discovery of the drug which is used to treat many types of complex diseases. Virtual screening against a complex disease by general network estimation has become feasible with the development of network biology and system biology. More effective methods of computational estimation for the whole efficacy of a compound in a complex disease system are needed, given the distinct weightiness of the different target in a biological process and the standpoint that partial inhibition of several targets can be more efficient than the complete inhibition of a single target. We developed a novel approach by integrating the affinity predictions from multi-target docking studies with biological network efficiency analysis to estimate the anticoagulant activities of compounds. From results of network efficiency calculation for human clotting cascade, factor Xa and thrombin were identified as the two most fragile enzymes, while the catalytic reaction mediated by complex IXa:VIIIa and the formation of the complex VIIIa:IXa were recognized as the two most fragile biological matter in the human clotting cascade system. Furthermore, the method which combined network efficiency with molecular docking scores was applied to estimate the anticoagulant activities of a serial of argatroban intermediates and eight natural products respectively. The better correlation (r = 0.671) between the experimental data and the decrease of the network deficiency suggests that the approach could be a promising computational systems biology tool to aid identification of anticoagulant activities of compounds in drug discovery. This article proposes a network-based multi-target computational estimation method for anticoagulant activities of compounds by

  16. Enhanced quantum efficiency in blue-emitting polymer/dielectric nanolayer nanocomposite light-emitting devices

    International Nuclear Information System (INIS)

    Park, Jong Hyeok; Lim, Yong Taik; Park, O Ok; Yu, Jae-Woong; Kim, Jai Kyeong; Kim, Young Chul

    2004-01-01

    Light-emitting devices based on environmentally stable, blue-emitting polymer/dielectric nanolayer nanocomposites were fabricated by blending poly(di-octylfluorene) (PDOF) with organo-clay. By reducing the excimer formation that leads to long wavelength tails, the photoluminescence (PL) and electroluminescence (EL) color purity of the device was enhanced. When a conjugated polymer/dielectric nanolayer nanocomposite is applied to an EL device, we expect an electronic structure similar to the well-known quantum well in small nanodomains. The ratio of PDOF/organo-clay was regulated from 2:1 to 0.5:1 (w/w). The light-emitting device of 0.5:1 (w/w) blend demonstrated the highest quantum efficiency (QE), 0.72% (ph/el), which is ∼500 times higher value compared with that of the pure PDOF layer device. However, the driving voltage of the nanocomposite devices tended to increase with increasing organo-clay content

  17. Sexual Differences in Chemical Composition and Aroma-active Compounds of Essential Oil from Flower Buds of Eurya japonica.

    Science.gov (United States)

    Miyazawa, Mitsuo; Usami, Atsushi; Tanaka, Takio; Tsuji, Kaoru; Takehara, Manami; Hori, Yuki

    2016-01-01

    This study was conducted to determine the composition of essential oil from buds of male and female Eurya japonica flowers and to determine the aroma-active compounds of this plant by gas chromatography-mass spectrometry (GC-MS), sensory evaluation, and odor activity values (OAV). The oils contained eighty-five compounds. We identified for the first time forty-four compounds in E. japonica. Through sensory evaluation, nineteen aroma-active compounds were identified by gas chromatography-olfactometry (GC-O). Because the chemical composition can affect the interaction between plants and herbivorous insects, our results suggest that essential oils from male and female flower buds of E. japonica differently affect herbivores. Sexual differences in essential oils deserve further investigations in this plant-insect system.

  18. DNA-damaging activity of a cinnamate derivative and further compounds from Cinnamomum australe (Lauraceae)

    International Nuclear Information System (INIS)

    Carbonezi, Carlos Alberto; Lopes, Marcia Nasser; Silva, Dulce Helena Siqueira; Araujo, Angela Regina; Bolzani, Vanderlan da Silva; Young, Maria Claudia Marx; Silva, Marcelo Rogerio da

    2004-01-01

    The bioactive compound trans-3'-methylsulphonylallyl trans-cinnamate (1) along with the inactive iryelliptin (2) and (7R,8S,1'S)-Δ 8' -3',5'-dimethoxy-1',4'-dihydro-4'-oxo-7.0.2',8.1'-neolignan (3) were isolated from the leaves of Cinnamomum australe. The structures of these compounds were assigned by analysis of 1D and 2D NMR data and comparison with data registered in the literature for these compounds. The DNA-damaging activity of 1 is being described for the first time. (author)

  19. Pre-compound emission in low-energy heavy-ion interactions

    Directory of Open Access Journals (Sweden)

    Kumar Sharma Manoj

    2017-01-01

    Full Text Available Recent experimental studies have shown the presence of pre-compound emission component in heavy ion reactions at low projectile energy ranging from 4 to 7 MeV/nucleons. In earlier measurements strength of the pre-compound component has been estimated from the difference in forward-backward distributions of emitted particles. Present measurement is a part of an ongoing program on the study of reaction dynamics of heavy ion interactions at low energies aimed at investigating the effect of momentum transfer in compound, precompound, complete and incomplete fusion processes in heavy ion reactions. In the present work on the basis of momentum transfer the measurement of the recoil range distributions of heavy residues has been used to decipher the components of compound and pre-compound emission processes in the fusion of 16O projectile with 159Tb and 169Tm targets. The analysis of recoil range distribution measurements show two distinct linear momentum transfer components corresponding to pre-compound and compound nucleus processes are involved. In order to obtain the mean input angular momentum associated with compound and pre-compound emission processes, an online measurement of the spin distributions of the residues has been performed. The analysis of spin distribution indicate that the mean input angular momentum associated with pre-compound products is found to be relatively lower than that associated with compound nucleus process. The pre-compound components obtained from the present analysis are consistent with those obtained from the analysis of excitation functions.

  20. Pre-compound emission in low-energy heavy-ion interactions

    Science.gov (United States)

    Sharma, Manoj Kumar; Shuaib, Mohd.; Sharma, Vijay R.; Yadav, Abhishek; Singh, Pushpendra P.; Singh, Devendra P.; Unnati; Singh, B. P.; Prasad, R.

    2017-11-01

    Recent experimental studies have shown the presence of pre-compound emission component in heavy ion reactions at low projectile energy ranging from 4 to 7 MeV/nucleons. In earlier measurements strength of the pre-compound component has been estimated from the difference in forward-backward distributions of emitted particles. Present measurement is a part of an ongoing program on the study of reaction dynamics of heavy ion interactions at low energies aimed at investigating the effect of momentum transfer in compound, precompound, complete and incomplete fusion processes in heavy ion reactions. In the present work on the basis of momentum transfer the measurement of the recoil range distributions of heavy residues has been used to decipher the components of compound and pre-compound emission processes in the fusion of 16O projectile with 159Tb and 169Tm targets. The analysis of recoil range distribution measurements show two distinct linear momentum transfer components corresponding to pre-compound and compound nucleus processes are involved. In order to obtain the mean input angular momentum associated with compound and pre-compound emission processes, an online measurement of the spin distributions of the residues has been performed. The analysis of spin distribution indicate that the mean input angular momentum associated with pre-compound products is found to be relatively lower than that associated with compound nucleus process. The pre-compound components obtained from the present analysis are consistent with those obtained from the analysis of excitation functions.

  1. Salt lakes of Western Australia - Natural abiotic formation of volatile organic compounds

    Science.gov (United States)

    Krause, T.; Studenroth, S.; Mulder, I.; Tubbesing, C.; Kotte, K.; Ofner, J.; Junkermann, W.; Schöler, H. F.

    2012-04-01

    Western Australia is a semi-/arid region that is heavily influenced by global climate change and agricultural land use. The area is known for its many ephemeral saline and hypersaline lakes with a wide range of hydrogeochemical parameters that have gradually changed over the last fifty years. Historically, the region was covered by eucalyptus trees and shrubs, but was cleared mainly within 10 years after WWII to make room for wheat and live stock. After the clearance of the deep rooted native plants the groundwater started to rise, bringing increased amounts of dissolved salts and minerals to the surface and discharging them into streams and lakes. Thus most of Western Australia is influenced by secondary salinisation (soil salting) [1]. Another problem is that the discharged minerals affect the pH of ground and surface water, which ranges from acidic to slightly basic. During the 2011 campaign surface water was measured with a pH between 2.5 and 7.1. Another phenomenon in Western Australia is the decrease of rainfall over the last decades assumed to be linked to the secondary salinisation. The rising saline and mineral rich groundwater increases the biotical and abiotical activity of the salt lakes. Halogenated and non-halogenated volatile organic compounds emitted from those lakes undergo fast oxidation and chemical reactions to form small particles modifying cloud microphysics and thus suppressing rain events [2]. Our objective is to gain a better understanding of this extreme environment with its hypersaline acidic lakes with regard to the potential abiotic formation of volatile organic compounds and its impact on the local climate. In spring 2011 fifty-three sediment samples from ten salt lakes in the Lake King region where taken, freeze-dried and ground. In order to simulate the abiotic formation of volatile organic compounds the soil samples were resuspended with water in gas-tight headspace vials. The headspace was measured using a purge and trap GC

  2. Printing method for organic light emitting device lighting

    Science.gov (United States)

    Ki, Hyun Chul; Kim, Seon Hoon; Kim, Doo-Gun; Kim, Tae-Un; Kim, Snag-Gi; Hong, Kyung-Jin; So, Soon-Yeol

    2013-03-01

    Organic Light Emitting Device (OLED) has a characteristic to change the electric energy into the light when the electric field is applied to the organic material. OLED is currently employed as a light source for the lighting tools because research has extensively progressed in the improvement of luminance, efficiency, and life time. OLED is widely used in the plate display device because of a simple manufacture process and high emitting efficiency. But most of OLED lighting projects were used the vacuum evaporator (thermal evaporator) with low molecular. Although printing method has lower efficiency and life time of OLED than vacuum evaporator method, projects of printing OLED actively are progressed because was possible to combine with flexible substrate and printing technology. Printing technology is ink-jet, screen printing and slot coating. This printing method allows for low cost and mass production techniques and large substrates. In this research, we have proposed inkjet printing for organic light-emitting devices has the dominant method of thick film deposition because of its low cost and simple processing. In this research, the fabrication of the passive matrix OLED is achieved by inkjet printing, using a polymer phosphorescent ink. We are measured optical and electrical characteristics of OLED.

  3. Cationic compounds with activity against multidrug-resistant bacteria: interest of a new compound compared with two older antiseptics, hexamidine and chlorhexidine.

    Science.gov (United States)

    Grare, M; Dibama, H Massimba; Lafosse, S; Ribon, A; Mourer, M; Regnouf-de-Vains, J-B; Finance, C; Duval, R E

    2010-05-01

    Use of antiseptics and disinfectants is essential in infection control practices in hospital and other healthcare settings. In this study, the in vitro activity of a new promising compound, para-guanidinoethylcalix[4]arene (Cx1), has been evaluated in comparison with hexamidine (HX) and chlorhexidine (CHX), two older cationic antiseptics. The MICs for 69 clinical isolates comprising methicillin-resistant Staphylococcus aureus, methicillin-sensitive S. aureus, coagulase-negative staphylococci (CoNS) (with or without mecA), vancomycin-resistant enterococci, Enterobacteriaceae producing various beta-lactamases and non-fermenting bacilli (Pseudomonas aeruginosa, Acinetobacter baumanii, Stenotrophomonas maltophilia) were determined. Cx1 showed similar activity against S. aureus, CoNS and Enterococcus spp., irrespective of the presence of mecA or van genes, or associated resistance genes, with very good activity against CoNS (MIC compound against all strains, with broad-spectrum and conserved activity against multidrug-resistant strains. HX showed a lower activity, essentially against Gram-positive strains. Consequently, the differences observed with respect to Cx1 suggest that they are certainly not the consequence of antibiotic resistance phenotypes, but rather the result of membrane composition modifications (e.g. of lipopolysaccharide), or of the presence of (activated) efflux-pumps. These results raise the possibility that Cx1 may be a potent new antibacterial agent of somewhat lower activity but significantly lower toxicity than CHX.

  4. Purely organic thermally activated delayed fluorescence (TADF) materials for organic light-emitting diodes (OLEDs)

    OpenAIRE

    Wong, Michael Y.; Zysman-Colman, Eli

    2017-01-01

    We thank the University of St Andrews for support. EZ-C thanks the Leverhulme Trust for financial support (RPG-2016-047). and the EPSRC (EP/P010482/1) for financial support. The design of thermally activated delayed fluorescence (TADF) materials both as emitters and as hosts is an exploding area of research. The replacement of phosphorescent metal complexes with inexpensive organic compounds in electroluminescent (EL) devices that demonstrate comparable performance metrics is paradigm shif...

  5. Regulation of hazardous air pollutants emitted from fossil-fired boilers

    International Nuclear Information System (INIS)

    Hendrickson, P.L.; Daellenbach, K.K.

    1993-01-01

    The changes made in section 112 of the Clean Air Act by the 1990 Amendments to the Act will affect the regulation of hazardous air pollutants (HAPs) emitted by fossil-fired boilers. The 1990 Amendments designated 189 chemicals/compounds as HAPS. Major and area sources of these pollutants in categories designated by the Environmental Protection Agency (EPA) will be subject to emission standards set by EPA. Industrial and institutional/commercial boilers are two such categories of HAPs designated by EPA for which emission standards will be issued. Fossil-fired boilers can emit a variety of HAPS. All or a portion of such emissions that exceed designated thresholds are likely to be regulated. This paper discusses how the 1990 amendments impact fossil-fired boilers. The steps are outlined which can be taken by owners of industrial and institutional/commercial boilers before the final emission standards are issued. These steps include participation in EPA's standard setting process, participation in EPA's early reduction program to delay the time when compliance with the maximum achievable control technology (MACT) standard is required, and consideration of any planned modifications to a facility which might subject that facility to a MACT standard set in advance of the EPA-set standard

  6. Alpha-emitting 'hot particles' in the vicinity of BNFL Sellafield, Cumbria

    International Nuclear Information System (INIS)

    Whittall, A.J.; Tossell, P.J.

    2000-01-01

    In a survey of environmental samples in the vicinity of BNFL Sellafield, two alpha-emitting radioactive particles were found in samples of grass. One particle appears to be of mineral origin, the other was not definitively identified, but may be a fragment of fuel cladding. Conservative estimates of the activities of these particles are very low. The abundance of radioactive particles in the terrestrial food chain appears to be low, with no evidence for any alpha-emitting hot particles in foodstuffs for consumption by humans. Results suggest that there is no significant dose to man through inhalation or ingestion pathways. (author)

  7. Pyrazole compound BPR1P0034 with potent and selective anti-influenza virus activity

    Directory of Open Access Journals (Sweden)

    Yeh Jiann-Yih

    2010-02-01

    Full Text Available Abstract Background Influenza viruses are a major cause of morbidity and mortality around the world. More recently, a swine-origin influenza A (H1N1 virus that is spreading via human-to-human transmission has become a serious public concern. Although vaccination is the primary strategy for preventing infections, influenza antiviral drugs play an important role in a comprehensive approach to controlling illness and transmission. In addition, a search for influenza-inhibiting drugs is particularly important in the face of high rate of emergence of influenza strains resistant to several existing influenza antivirals. Methods We searched for novel anti-influenza inhibitors using a cell-based neutralization (inhibition of virus-induced cytopathic effect assay. After screening 20,800 randomly selected compounds from a library from ChemDiv, Inc., we found that BPR1P0034 has sub-micromolar antiviral activity. The compound was resynthesized in five steps by conventional chemical techniques. Lead optimization and a structure-activity analysis were used to improve potency. Time-of-addition assay was performed to target an event in the virus life cycle. Results The 50% effective inhibitory concentration (IC50 of BPR1P0034 was 0.42 ± 0.11 μM, when measured with a plaque reduction assay. Viral protein and RNA synthesis of A/WSN/33 (H1N1 was inhibited by BPR1P0034 and the virus-induced cytopathic effects were thus significantly reduced. BPR1P0034 exhibited broad inhibition spectrum for influenza viruses but showed no antiviral effect for enteroviruses and echovirus 9. In a time-of-addition assay, in which the compound was added at different stages along the viral replication cycle (such as at adsorption or after adsorption, its antiviral activity was more efficient in cells treated with the test compound between 0 and 2 h, right after viral infection, implying that an early step of viral replication might be the target of the compound. These results suggest

  8. The content of sensory active compounds and flavour of several types of yogurts

    Directory of Open Access Journals (Sweden)

    Eva Vítová

    2010-01-01

    Full Text Available The aim of this work was to identify and quantify several sensory active compounds in various types of yogurts using gas chromatography and simultaneously to judge their influence on flavour of yogurts using sensory analysis. In total 4 types of white and 10 types of flavoured yogurts (creamy and low-fat with various flavourings, produced in Dairy Valašské Meziříčí, Ltd., were analysed. The highest content of sensory active compounds (P < 0.05 was found in strawberry yogurts, with high amount of ethyl butyrate. Excepting ethanol no significant differences (P < 0.05 were found between low-fat and creamy varieties. The total content of sensory active compounds in white yogurts was significantly (P < 0.05 lower than in flavoured fruit types. The highest content was in low-fat and lowest in white bio yoghurts. Flavour of yogurts was evaluated sensorially using scale and ranking test. All creamy yogurt varieties were evaluated as significantly (P < 0.05 more tasty than low-fat ones. Similarly in case of white yogurts creamy yogurts were evaluated as the most tasty and low-fat ones as the worst. Bio yogurts were evaluated equally tasty as classic yogurts with the same fat content.

  9. Anti-Alzheimer's disease activity of compounds from the root bark of Morus alba L.

    Science.gov (United States)

    Kuk, Eun Bi; Jo, A Ra; Oh, Seo In; Sohn, Hee Sook; Seong, Su Hui; Roy, Anupom; Choi, Jae Sue; Jung, Hyun Ah

    2017-03-01

    The inhibition of acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and β-site amyloid precursor protein cleaving enzyme 1 (BACE1) plays important roles in prevention and treatment of Alzheimer's disease (AD). Among the individual parts of Morus alba L. including root bark, branches, leaves, and fruits, the root bark showed the most potent enzyme inhibitory activities. Therefore, the aim of this study was to evaluate the anti-AD activity of the M. alba root bark and its isolate compounds, including mulberrofuran G (1), albanol B (2), and kuwanon G (3) via inhibition of AChE, BChE, and BACE1. Compounds 1 and 2 showed strong AChE- and BChE-inhibitory activities; 1-3 showed significant BACE1 inhibitory activity. Based on the kinetic study with AChE and BChE, 2 and 3 showed noncompetitive-type inhibition; 1 showed mixed-type inhibition. Moreover, 1-3 showed mixed-type inhibition against BACE1. The molecular docking simulations of 1-3 demonstrated negative binding energies, indicating a high affinity to AChE and BACE1. The hydroxyl group of 1-3 formed hydrogen bond with the amino acid residues located at AChE and BACE1. Consequently, these results indicate that the root bark of M. alba and its active compounds might be promising candidates for preventive and therapeutic agents for AD.

  10. The use of ionic salt dyes as amorphous, thermally stable emitting layers in organic light-emitting diodes

    Science.gov (United States)

    Chondroudis, Konstantinos; Mitzi, David B.

    2000-01-01

    The conversion of two neutral dye molecules (D) to ionic salts (H2N-D-NH2ṡ2HX) and their utilization as emitting layers in organic light-emitting diodes (OLEDs) is described. The dye salts, AEQTṡ2HCl and APTṡ2HCl, can be deposited as amorphous films using conventional evaporation techniques. X-ray diffraction and scanning electron microscopy analysis, coupled with thermal annealing studies, demonstrate the resistance of the films to crystallization. This stability is attributed to strong ionic forces between the relatively rigid molecules. OLEDs incorporating such salts for emitting layers exhibit better thermal stability compared with devices made from the corresponding neutral dyes (H2N-D-NH2). These results suggest that ionic salts may more generally enable the formation of thermally stable, amorphous emitting, and charge transporting layers.

  11. Immunomodulatory potencies of isolated compounds from Crataegus azarolus through their antioxidant activities.

    Science.gov (United States)

    Mustapha, Nadia; Mokdad-Bzéouich, Imèn; Sassi, Aicha; Abed, Besma; Ghedira, Kamel; Hennebelle, Thierry; Chekir-Ghedira, Leila

    2016-06-01

    The search of natural immunomodulatory agents has become an area of great interest in order to reduce damage to the human body. In this study, the immunomodulatory potential of Crataegus azarolus and its isolated hyperoside on mouse lymphocytes and macrophages in vitro was assessed. The effect of C. azarolus natural compounds on splenocytes proliferation, natural killer (NK) and cytotoxic T lymphocytes (CTL) activities, and on macrophage-mediated cytotoxicity were assessed by MTT test. Phagocytic activity and inhibition of nitric oxide (NO) release by macrophages were also evaluated. The antioxidant capacity of these products was evaluated by determining their cellular antioxidant activity (CAA) in splenocytes and macrophages. Depending on the concentrations, both ethyl acetate (EA) extract and hyperoside (Hyp) from C. azarolus affect macrophage functions by modulating their lysosomal enzyme activity and nitric oxide release. Whereas, the above-mentioned products significantly promote LPS and lectin-stimulated splenocyte proliferation, implying a potential activation of lymphocytes B and T enhancing humoral and cellular immune responses. Moreover, EA extract and Hyp could enhance the activity of NK and T lymphocytes cells, as well as the macrophages-mediated cytotoxicity against B16F10 cells. The anti-inflammatory activity was concomitant with the cellular antioxidant effect of the tested compounds against macrophages and splenocytes. Collectively, C. azarolus and its isolated hyperoside exhibited an immunomodulatory effect through their antioxidant activity. These findings suggest that C. azarolus should be explored as a novel potential immunomodulatory agent for the treatment of inflammatory diseases.

  12. High Intensity Organic Light-emitting Diodes

    Science.gov (United States)

    Qi, Xiangfei

    This thesis is dedicated to the fabrication, modeling, and characterization to achieve high efficiency organic light-emitting diodes (OLEDs) for illumination applications. Compared to conventional lighting sources, OLEDs enabled the direct conversion of electrical energy into light emission and have intrigued the world's lighting designers with the long-lasting, highly efficient illumination. We begin with a brief overview of organic technology, from basic organic semiconductor physics, to its application in optoelectronics, i.e. light-emitting diodes, photovoltaics, photodetectors and thin-film transistors. Due to the importance of phosphorescent materials, we will focus on the photophysics of metal complexes that is central to high efficiency OLED technology, followed by a transient study to examine the radiative decay dynamics in a series of phosphorescent platinum binuclear complexes. The major theme of this thesis is the design and optimization of a novel architecture where individual red, green and blue phosphorescent OLEDs are vertically stacked and electrically interconnected by the compound charge generation layers. We modeled carrier generation from the metal-oxide/doped organic interface based on a thermally assisted tunneling mechanism. The model provides insights to the optimization of a stacked OLED from both electrical and optical point of view. To realize the high intensity white lighting source, the efficient removal of heat is of a particular concern, especially in large-area devices. A fundamental transfer matrix analysis is introduced to predict the thermal properties in the devices. The analysis employs Laplace transforms to determine the response of the system to the combined effects of conduction, convection, and radiation. This perspective of constructing transmission matrices greatly facilitates the calculation of transient coupled heat transfer in a general multi-layer composite. It converts differential equations to algebraic forms, and

  13. Inhibition of dehydrogenase activity in petroleum refinery wastewater bacteria by phenolic compounds

    Directory of Open Access Journals (Sweden)

    Gideon C. Okpokwasili

    2010-04-01

    Full Text Available The toxicity of phenol, 2-nitrophenol, 4-nitrophenol, 2,4-dinitrophenol, 2-chlorophenol, 4-chlorophenol, 4-bromophenol and 3,5-dimethylphenol on Pseudomonas, Bacillus and Escherichia species isolated from petroleum refinery wastewater was assessed via inhibition of dehydrogenase enzyme activity. At low concentrations, 2-nitrophenol, 2-chlorophenol, 4-chlorophenol, 4-bromophenol and 3,5-dimethylphenol stimulated dehydrogenase activity and at sufficient concentrations, phenolic compounds inhibited dehydrogenase activities. Generally, phenol is less toxic than substituted phenols. Estimations of the degree of inhibition/stimulation of dehydrogenase activities showed significant dose-dependent responses that are describable by logistic functions. The toxicity thresholds varied significantly (P < 0.05 among the bacterial strains and phenolic compounds. The median inhibitory concentrations (IC50s ranged from 4.118 ± 0.097 mg.L-1 for 4-nitrophenol against Pseudomonas sp. DAF1 to 1407.997 ± 7.091 mg.L-1 for phenol against Bacillus sp. DISK1. This study suggested that the organisms have moderate sensitivity to phenols and have the potential to be used as indicators for assessment of chemical toxicity. They could also be used as catalysts for degradation of phenols in effluents.

  14. Intra-operative nuclear imaging based on positron-emitting radiotracers

    International Nuclear Information System (INIS)

    Shakir, Dzhoshkun Ismail

    2014-01-01

    Positron-emitting radiotracers are an important part of nuclear medical imaging processes. Besides the very famous glucose analog [ 18 F]FDG, many not so well known ones exist, among them the particularly interesting amino acid-based tracers like [ 18 F]FET. Although peri-operative imaging with positron-emitting radiotracers has become state-of- the-art in cases of many types of cancer, their capability is not fully exploited in the operating room yet. In this thesis we explore two intra-operative nuclear imaging modalities exploiting different aspects of positron radiation towards quality assurance in challenging surgical treatment scenarios. The first modality freehand PET provides a tomographic image of a volume of interest and aims at minimizing invasiveness by assisting the surgeon in pinpointing target structures marked with a radiotracer. The second imaging modality epiphanography generates an image of the radiotracer distribution on a surface of interest and aims at providing a means for improving the control of tumor resection margins. The word epiphanography is a compound of the Greek words επιφανεια (epiphaneia) for surface and ζωγραφια (ographia) for image, and hence means the image of the surface similar to the compound τομοζ (tomos) for slice/volume and ζωγραφια (ographia) for image, meaning the image of the volume, i.e. tomography. To our knowledge this is the first use of the word epiphanography in the context of nuclear medical imaging. In this thesis we present our approach to modeling, developing and calibrating these two novel imaging modalities. In addition, we present our work towards their clinical integration. In the case of freehand PET, we have already acquired the first intra-operative datasets of a patient. We present this first experience in the operating room together with our phantom studies. In the case of epiphanography, we present our phantom studies with neurosurgeons towards the integration of this

  15. Synthesis, reactions and biological activity of some new bis-heterocyclic ring compounds containing sulphur atom

    Science.gov (United States)

    2013-01-01

    Background The derivatives of thieno[2,3-b]thiophene belong to a significant category of heterocyclic compounds, which have shown a wide spectrum of medical and industrial application. Results A new building block with two electrophilic center of thieno[2,3-b]thiophene derivatives 2 has been reported by one-pot reaction of diketone derivative 1 with Br2/AcOH in excellent yield. A variety of heteroaromatics having bis(1H-imidazo[1,2a] benzimidazole), bis(1H-imidazo[1,2-b][1,2,4]triazole)-3-methyl-4-phenylthieno[2,3-b]thiophene derivatives, dioxazolo-, dithiazolo-, and 1H-imidazolo-3-methyl-4-phenylthieno[2,3-b]thiophene derivatives as well pyrrolo, thiazolo -3-methyl-4-phenylthieno[2,3-b]thiophene derivatives have been designed, synthesized, characterized, and evaluated for their biological activity. Compounds 3–9 showed good bioassay result. These new derivatives were evaluated for anti-cancer activity against PC-3 cell lines, in vitro antioxidant potential and β-glucuronidase and α-glucosidase inhibitory activities. Compound 3 (IC50 = 56.26 ± 3.18 μM) showed a potent DPPH radical scavenging antioxidant activity and found to be more active than standard N-acetylcystein (IC50 = 105.9 ± 1.1 μM). Compounds 8a (IC50 = 13.2 ± 0.34 μM) and 8b (IC50 = 14.1 ± 0.28 μM) found as potent inhibitor of α-glucusidase several fold more active than the standard acarbose (IC50 = 841 ± 1.73 μM). Most promising results were obtained in β-glucuronidase enzyme inhibition assay. Compounds 5 (IC50 = 0.13 ± 0.019 μM), 6 (IC50 = 19.9 ± 0.285 μM), 8a (IC50 = 1.2 ± 0.0785 μM) and 9 (IC50 = 0.003 ± 0.09 μM) showed a potent inhibition of β-glucuronidase. Compound 9 was found to be several hundred fold more active than standard D-Saccharic acid 1,4-lactone (IC50 = 45.75 ± 2.16 μM). Conclusions Synthesis, characterization, and in vitro biological activity of a series of

  16. Positron emitting radionuclides for South Africa

    International Nuclear Information System (INIS)

    Wynchbank, S.; Van der Walt, T.N.; Sharpey-Shafer, J.

    2004-01-01

    Full text: In South Africa there are currently two projects underway to supply and utilise positron emitting radionuclides for imaging in clinical nuclear medicine facilities. The advantages and applications of such radio nuclides are numerous and well known. However the premier initial application will be to employ 1BF, at first in the compound fluorine-18 fluorodeoxyglucose ( 18 F)-FDG, for patients with cancers and neoplasms. The two projects are sited at iThemba LABS, where production of a generator supplying 66 Ga and the provision of ( 18 F]-FDG, are in an advanced state of planning; the former already fully financed by the Innovation Fund of the National Research Foundation. The two positron emitting radionuclides, 18 F and 68 Ge, will be produced using a cyclotron induced reaction on 1802 and Ga, respectively, at iThemba LABS. The 68 Ge/ 68 Ga generator consists of an anion exchanger loaded with 68 Ge, which decays to 68 Ga. The resulting radiopharmaceuticals, ( 18 F]-FDG and 68 Ga citrate, will be produced by the Radionuclide Production Group of iThemba LABS, using well described methods. However the structures and processes to be used in the generator to provide 68 Ga are novel and will be explained. Initially provision of the CBF]-FDG will be to selected clinical medicine facilities in the Western Cape and Gauteng. It should be noted that the logistical problems of providing this radiopharmaceutical (which are much complicated by its short half life of 109.7 min) to Gauteng, were shown to be surmountable in the 1970s, by a regular delivery of 18 F between Gauteng and Cape Town, after the advent of a commercial service using jet aircraft. The obvious requirement that there should be appropriate nuclear medicine facilities to image patients, at the sites to which the positron emitting radiopharmaceuticals will be supplied, has been addressed. Proposed solutions will be outlined, in terms of a dedicated positron emission tomography (PET) camera and a gamma

  17. Comparative potential of black tea leaves waste to granular activated carbon in adsorption of endocrine disrupting compounds from aqueous solution

    Directory of Open Access Journals (Sweden)

    A.O. Ifelebuegu

    2015-07-01

    Full Text Available The adsorption properties and mechanics of selected endocrine disrupting compounds; 17 β-estradiol, 17 α – ethinylestradiol and bisphenol A on locally available black tea leaves waste and granular activated carbon were investigated. The results obtained indicated that the kinetics of adsorption were pH, adsorbent dose, contact time and temperature dependent with equilibrium being reached at 20 to 40 minutes for tea leaves waste and 40 to 60 minutes for granular activated compound. Maximum adsorption capacities of 3.46, 2.44 and 18.35 mg/g were achieved for tea leaves waste compared to granular activated compound capacities of 4.01, 2.97 and 16.26 mg/g for 17 β- estradiol, 17 α-ethinylestradiol and bisphenol A respectively. Tea leaves waste adsorption followed pseudo-first order kinetics while granular activated compound fitted better to the pseudo-second order kinetic model. The experimental isotherm data for both tea leaves waste and granular activated compound showed a good fit to the Langmuir, Freundlich and Temkin isotherm models with the Langmuir model showing the best fit. The thermodynamic and kinetic data for the adsorption indicated that the adsorption process for tea leaves waste was predominantly by physical adsorption while the granular activated compound adsorption was more chemical in nature. The results have demonstrated the potential of waste tea leaves for the adsorptive removal of endocrine disrupting compounds from water.

  18. Dioxin-like activity of environmental compounds in human blood and environmental samples

    DEFF Research Database (Denmark)

    Long, Manhai; Bonefeld-Jørgensen, Eva Cecilie

    2012-01-01

    and humans. We found that some pesticides, plasticizers and phytoestrogens can activate the AhR, and the combined effect of compounds with no or weak AhR potency cannot be ignored. The significant DL-activity in the wastewater effluent indicates the treatment is not sufficient to prevent contamination...... of surface waters with dioxins. Our results from human studies suggest that the serum DL-activity reflect the complex mixture of persistent organic pollutants (POPs). Greenlandic Inuit had lower serum DL-activity level compared to Europeans, probably due to long distance from the dioxin sources and UV...

  19. Chemical composition and antioxidant activity of phenolic compounds and essential oils from Calamintha nepeta L.

    Science.gov (United States)

    Khodja, Nabyla Khaled; Boulekbache, Lila; Chegdani, Fatima; Dahmani, Karima; Bennis, Faiza; Madani, Khodir

    2018-05-24

    Background Essential oils, infusion and decoction extracts of Calamintha nepeta L. were evaluated for their bioactive substances (polyphenols and essential oils) and antioxidant activities. Methods The amounts of phenolic compounds were determined by colorimetric assays and identified by high performance and liquid chromatography coupled with ultraviolet detector (HPLC-UV) method. The chemical composition of essential oils was determined by gas-chromatography coupled with mass spectrometry (GC/MS) method. For the evaluation of the antioxidant activity of essential oils and extracts, two different assays (reducing power and DPPH radical scavenging activity) were used. Results Infusion extract presented the highest phenolic content, followed by the decoction one, while the lowest amount was observed in essential oils. The amount of flavonoids of the decocted extract was higher than that of the infused one. The phenolic profile of C. nepeta infusion and decoction extracts revealed the presence of 28 and 13 peaks, respectively. Four phenolics compounds were identified in infusion (gallic acid (GA), rosmarinic acid (RA), caffeine (C) and caffeic acid (CA)) and two were identified in decoction (GA and RA). The chemical composition of essential oils revealed the presence of 29 compounds, accounting for the 99.7% of the total oils. Major compounds of essential oil (EO) were trans-menthone (50.06%) and pulegone (33.46%). Infusion and decoction extracts revealed an interesting antioxidant activity which correlates positively with their total phenolic contents. Conclusions These results showed that Calamintha nepeta could be considered as a valuable source of phenolics and essential oils with potent antioxidant activity.

  20. Emission and role of biogenic volatile organic compounds in biosphere

    International Nuclear Information System (INIS)

    Saleem, A.R.

    2013-01-01

    Plants are an essential part of the biosphere. Under the influence of climate change, plants respond in multiple ways within the ecosystem. One such way is the release of assimilated carbon back to the atmosphere in form of biogenic volatile organic compounds (BVOCs), which are produced by plants and are involved in plant growth, reproduction, defense and other . These compounds are emitted from vegetation into the atmosphere under different environmental situations. Plants produce an extensive range of BVOCs, including isoprenoids, sequisterpenes, aldehydes, alcohols and terpenes in different tissues above and below the ground. The emission rates vary with various environmental conditions and the plant growth stage in its life span.BVOCs are released under biotic and abiotic stress changes, like heat, drought, land-use changes, higher atmospheric CO concentrations, increased UV radiation and insect or disease attack. Plants emit BVOCs in atmosphere in order to avoid stress, and adapt to harsh circumstances. These compounds also have a significant role in plant-plant interaction, communication and competition. BVOCs have the ability to alter atmospheric chemistry; they readily react with atmospheric pollutant gases under high temperature and form tropospheric ozone, which is a potent air pollutant for global warming and disease occurrence. BVOCs may be a cause of photochemical smog and increase the stay of other GHGs in the atmosphere. Therefore, further study is required to assess the behavior of BVOCs in the biosphere as well as the atmosphere. (author)

  1. Spectrum study of top-emitting organic light-emitting devices with micro-cavity structure

    International Nuclear Information System (INIS)

    Liu Xiang; Wei Fuxiang; Liu Hui

    2009-01-01

    Blue and white top-emitting organic light-emitting devices OLEDs with cavity effect have been fabricated. TBADN:3%DSAPh and Alq 3 :DCJTB/TBADN:TBPe/Alq 3 :C545 were used as emitting materials of microcavity OLEDs. On a patterned glass substrate, silver was deposited as reflective anode, and copper phthalocyanine (CuPc) layer as HIL and 4'-bis[N-(1-Naphthyl)- N-phenyl-amino]biphenyl (NPB) layer as HTL were made. Al/Ag thin films were made as semi-transparent cathode with a transmittance of about 30%. By changing the thickness of indium tin oxide ITO, deep blue with Commission Internationale de L'Eclairage chromaticity coordinates (CIEx, y) of (0.141, 0.049) was obtained on TBADN:3%DSAPh devices, and different color (red, blue and green) was obtained on Alq 3 :DCJTB/TBADN:TBPe/Alq 3 :C545 devices, full width at half maxima (FWHM) was only 17 nm. The spectral intensity and FWHM of emission in cavity devices have also been studied.

  2. Inhibition of dehydrogenase activity in petroleum refinery wastewater bacteria by phenolic compounds

    OpenAIRE

    Gideon C. Okpokwasili; Christian Okechukwu Nweke

    2010-01-01

    The toxicity of phenol, 2-nitrophenol, 4-nitrophenol, 2,4-dinitrophenol, 2-chlorophenol, 4-chlorophenol, 4-bromophenol and 3,5-dimethylphenol on Pseudomonas, Bacillus and Escherichia species isolated from petroleum refinery wastewater was assessed via inhibition of dehydrogenase enzyme activity. At low concentrations, 2-nitrophenol, 2-chlorophenol, 4-chlorophenol, 4-bromophenol and 3,5-dimethylphenol stimulated dehydrogenase activity and at sufficient concentrations, phenolic compounds inhibi...

  3. Antibacterial and Cytotoxic Activity of Compounds Isolated from Flourensia oolepis

    Directory of Open Access Journals (Sweden)

    Mariana Belén Joray

    2015-01-01

    Full Text Available The antibacterial and cytotoxic effects of metabolites isolated from an antibacterial extract of Flourensia oolepis were evaluated. Bioguided fractionation led to five flavonoids, identified as 2′,4′-dihydroxychalcone (1, isoliquiritigenin (2, pinocembrin (3, 7-hydroxyflavanone (4, and 7,4′-dihydroxy-3′-methoxyflavanone (5. Compound 1 showed the highest antibacterial effect, with minimum inhibitory concentration (MIC values ranging from 31 to 62 and 62 to 250 μg/mL, against Gram-positive and Gram-negative bacteria, respectively. On further assays, the cytotoxic effect of compounds 1–5 was determined by MTT assay on acute lymphoblastic leukemia (ALL and chronic myeloid leukemia (CML cell lines including their multidrug resistant (MDR phenotypes. Compound 1 induced a remarkable cytotoxic activity toward ALL cells (IC50 = 6.6–9.9 μM and a lower effect against CML cells (IC50 = 27.5–30.0 μM. Flow cytometry was used to analyze cell cycle distribution and cell death by PI-labeled cells and by Annexin V/PI staining, respectively. Upon treatment, 1 induced cell cycle arrest in the G2/M phase accompanied by a strong induction of apoptosis. These results describe for the first time the antibacterial metabolites of F. oolepis extract, with 1 being the most effective. This chalcone also emerges as a selective cytotoxic agent against sensitive and resistant leukemic cells, highlighting its potential as a lead compound.

  4. Anoxic degradation of nitrogenous heterocyclic compounds by activated sludge and their active sites.

    Science.gov (United States)

    Xu, Peng; Han, Hongjun; Zhuang, Haifeng; Hou, Baolin; Jia, Shengyong; Wang, Dexin; Li, Kun; Zhao, Qian

    2015-05-01

    The potential for degradation of five nitrogenous heterocyclic compounds (NHCs), i.e., imidazole, pyridine, indole, quinoline, and carbazole, was investigated under anoxic conditions with acclimated activated sludge. Results showed that NHCs with initial concentration of 50 mg/L could be completely degraded within 60 hr. The degradation of five NHCs was dependent upon the chemical structures with the following sequence: imidazole>pyridine>indole>quinoline>carbazole in terms of their degradation rates. Quantitative structure-biodegradability relationship studies of the five NHCs showed that the anoxic degradation rates were correlated well with highest occupied molecular orbital. Additionally, the active sites of NHCs identified by calculation were confirmed by analysis of intermediates using gas chromatography and mass spectrometry. Copyright © 2015. Published by Elsevier B.V.

  5. Separation and Identification of Four New Compounds with Antibacterial Activity from Portulaca oleracea L.

    Directory of Open Access Journals (Sweden)

    Xia Lei

    2015-09-01

    Full Text Available The Portulaca oleracea L. (P. oleracea has been used to treat bacillary dysentery for thousands of years in China. Pharmacology studies on P. oleracea have also showed its significant antibacterial effects on the enteropathogenic bacteria, which might reveal the treatment of P. oleracea in cases of bacillary dysentery to some extent. To date, however, the therapeutic basis of P. oleracea treating on bacillary dysentery remains unknown. We determined the antibacterial effective fraction of P. oleracea in a previous study. The current study, which is based on our previous study, was first designed to isolate, identify and screen antibacterial active constituents from P. oleracea. As a result, four new compounds (1–4, portulacerebroside B (1, portulacerebroside C (2, portulacerebroside D (3 and portulaceramide A (4 along with five known compounds (5–9 were isolated, and structures were established by their physico-chemical constants and spectroscopic analysis. The antibacterial activities against common enteropathogenic bacteria were evaluated for all compounds and the new compounds 1–4 showed significant antibacterial effect on enteropathogenic bacteria in vitro, which might contribute to revealing the treatment of P. oleracea in cases of bacillary dysentery.

  6. Separation and Identification of Four New Compounds with Antibacterial Activity from Portulaca oleracea L.

    Science.gov (United States)

    Lei, Xia; Li, Jianmin; Liu, Bin; Zhang, Ning; Liu, Haiyang

    2015-09-10

    The Portulaca oleracea L. (P. oleracea) has been used to treat bacillary dysentery for thousands of years in China. Pharmacology studies on P. oleracea have also showed its significant antibacterial effects on the enteropathogenic bacteria, which might reveal the treatment of P. oleracea in cases of bacillary dysentery to some extent. To date, however, the therapeutic basis of P. oleracea treating on bacillary dysentery remains unknown. We determined the antibacterial effective fraction of P. oleracea in a previous study. The current study, which is based on our previous study, was first designed to isolate, identify and screen antibacterial active constituents from P. oleracea. As a result, four new compounds (1-4), portulacerebroside B (1), portulacerebroside C (2), portulacerebroside D (3) and portulaceramide A (4) along with five known compounds (5-9) were isolated, and structures were established by their physico-chemical constants and spectroscopic analysis. The antibacterial activities against common enteropathogenic bacteria were evaluated for all compounds and the new compounds 1-4 showed significant antibacterial effect on enteropathogenic bacteria in vitro, which might contribute to revealing the treatment of P. oleracea in cases of bacillary dysentery.

  7. Synthesis, Antiproliferative, and Multidrug Resistance Reversal Activities of Heterocyclic α,β-Unsaturated Carbonyl Compounds.

    Science.gov (United States)

    Sun, Ju-Feng; Hou, Gui-Ge; Zhao, Feng; Cong, Wei; Li, Hong-Juan; Liu, Wen-Shuai; Wang, Chunhua

    2016-10-01

    A series of heterocyclic α,β-unsaturated carbonyl compounds (1a-1d, 2a-2d, 3a-3d, 4a-3d, and 5a-5d) with 1,5-diaryl-3-oxo-1,4-pentadienyl pharmacophore were synthesized for the development of anticancer and multidrug resistance reverting agents. The antiproliferative activities were tested against nine human cancer cell lines. Approximately 73% of the IC50 values were below 5 μm, while 35% of these figures were submicromolar, and compounds 3a-3d with 4-trifluoro methyl in the arylidene benzene rings were the most potent, since their IC50 values are between 0.06 and 3.09 μm against all cancer cell lines employed. Meanwhile, their multidrug resistance reversal properties and cellular uptake were further examined. The data displayed that all of these compounds could reverse multidrug resistance, particularly, compounds 3a and 4a demonstrated both potent multidrug resistance reverting properties and strong antiproliferative activities, which can be taken as leading molecules for further research of dual effect agents in tumor chemotherapy. © 2016 John Wiley & Sons A/S.

  8. Volatile organic compound (VOC) emissions during malting and beer manufacture

    Science.gov (United States)

    Gibson, Nigel B.; Costigan, Gavin T.; Swannell, Richard P. J.; Woodfield, Michael J.

    Estimates have been made of the amounts of volatile organic compounds (VOCs) released during different stages of beer manufacture. The estimates are based on recent measurements and plant specification data supplied by manufacturers. Data were obtained for three main manufacturing processes (malting, wort processing and fermentation) for three commercial beer types. Some data on the speciation of emitted compounds have been obtained. Based on these measurements, an estimate of the total unabated VOC emission. from the U.K. brewing industry was calculated as 3.5 kta -1, over 95% of which was generated during barley malting. This value does not include any correction for air pollution control.

  9. Light emitting device having peripheral emissive region

    Science.gov (United States)

    Forrest, Stephen R

    2013-05-28

    Light emitting devices are provided that include one or more OLEDs disposed only on a peripheral region of the substrate. An OLED may be disposed only on a peripheral region of a substantially transparent substrate and configured to emit light into the substrate. Another surface of the substrate may be roughened or include other features to outcouple light from the substrate. The edges of the substrate may be beveled and/or reflective. The area of the OLED(s) may be relatively small compared to the substrate surface area through which light is emitted from the device. One or more OLEDs also or alternatively may be disposed on an edge of the substrate about perpendicular to the surface of the substrate through which light is emitted, such that they emit light into the substrate. A mode expanding region may be included between each such OLED and the substrate.

  10. Identification of Major Phenolic Compounds from Nephelium lappaceum L. and Their Antioxidant Activities

    Directory of Open Access Journals (Sweden)

    Nuansri Rakariyatham

    2010-03-01

    Full Text Available Nephelium lappaceum is a tropical fruit whose peel possesses antioxidant properties. Experiments on the isolation and identification of the active constituents were conducted, and on their antioxidant activity using a lipid peroxidation inhibition assay. The methanolic extract of N. lappaceum peels exhibited strong antioxidant properties. Sephadex LH-20 chromatography was utilized in the isolation of each constituent and the antioxidant properties of each was studied. The isolated compounds were identified as ellagic acid (EA (1, corilagin (2 and geraniin (3. These compounds accounted for 69.3% of methanolic extract, with geraniin (56.8% as the major component, and exhibited much greater antioxidant activities than BHT in both lipid peroxidation (77-186 fold and DPPH• (42-87 fold assays. The results suggest that the isolated ellagitannins, as the principal components of rambutan peels, could be further utilized as both a medicine and in the food industry.

  11. Identification of major phenolic compounds from Nephelium lappaceum L. and their antioxidant activities.

    Science.gov (United States)

    Thitilertdecha, Nont; Teerawutgulrag, Aphiwat; Kilburn, Jeremy D; Rakariyatham, Nuansri

    2010-03-09

    Nephelium lappaceum is a tropical fruit whose peel possesses antioxidant properties. Experiments on the isolation and identification of the active constituents were conducted, and on their antioxidant activity using a lipid peroxidation inhibition assay. The methanolic extract of N. lappaceum peels exhibited strong antioxidant properties. Sephadex LH-20 chromatography was utilized in the isolation of each constituent and the antioxidant properties of each was studied. The isolated compounds were identified as ellagic acid (EA) (1), corilagin (2) and geraniin (3). These compounds accounted for 69.3% of methanolic extract, with geraniin (56.8%) as the major component, and exhibited much greater antioxidant activities than BHT in both lipid peroxidation (77-186 fold) and DPPH* (42-87 fold) assays. The results suggest that the isolated ellagitannins, as the principal components of rambutan peels, could be further utilized as both a medicine and in the food industry.

  12. Procedure for the elaboration of extended sources beta and/or gamma emitting

    International Nuclear Information System (INIS)

    Tejera R, A.; Cortes P, A.; Becerril V, A.

    1991-12-01

    In the laboratory of radioactive standards they have been come manufacturing punctual sources gauged gamma emitting during several years. Before the demand of extended radioactive homogeneous sources of beta particles emitting, in particular with nuclides that are simultaneously gamma and beta emitting, it was designed a procedure for it elaboration based on the one that we use at the moment for the elaboration of the punctual gamma sources. This procedure consists on the integration of a compact group of this type of sources on a single extended support, sealed one of its faces with a film of transparent material in satisfactory grade to the beta particles. In this work this procedure is described and it is applied in the elaboration of two sources that its were requested by the Laguna Verde Central (CFE), one with area of 20 cm 2 and the other one of 100 cm 2 . The homogeneity, measure as the dispersion of the activities of the aliquot ones distributed in the active surfaces was inside 2%. The percentage of attenuation of the beta particles was also measured by the film (window) with the one that the sources were sealed. (Author)

  13. Characterization of aroma-active compounds in dry flower of Malva sylvestris L. by GC-MS-O analysis and OAV calculations.

    Science.gov (United States)

    Usami, Atsushi; Kashima, Yusei; Marumoto, Shinsuke; Miyazawa, Mitsuo

    2013-01-01

    In this study, the aroma-active compounds in the dried flower of Malva sylvestris L. were extracted by hydrodistillation and analyzed by gas chromatography-mass spectrometry (GC-MS), and gas chromatography-olfactometry (GC-O) and aroma extraction dilution analysis (AEDA). A light yellow oil with a sweet odor was obtained with a percentage yield of 0.039% (w/w), and 143 volatile compounds (89.86%) were identified by GC-MS. The main compounds were hexadecanoic acid (10.1%), pentacosane (4.8%) and 6,10,14-trimethyl-2-pentadecanone (4.1%). The essential oil consisted mainly of hydrocarbons (25.40%) followed by, alcohols (18.78%), acids (16.66%), ethers (5.01%) ketones (7.28%), esters(12.43%), aldehydes (2.30%) and others (2.00%). Of these compounds, 20 were determined by GC-O and AEDA, to be odor-active (FD (flavor dilution) factor ≥ 1). β-Damascenone (FD = 9, sweet), phenylacetaldehyde (FD = 8, floral, honey-like) and (E)-β-ocimene (FD = 8, spicy) were the most intense aroma-active compounds in M. sylvestris. In order to determine the relative contribution of each of the compounds to the aroma of M. sylvestris, odor activity values (OAVs) were used. β-Damascenone had the highest odor activity values (OAV) (50,700), followed by (E)-β-ionone (15,444) and decanal (3,510). In particular, β-damascenone had a high FD factors, and therefore, this compound was considered to be the main aroma-active components of the essential oil. On the basis of AEDA, OAVs, and sensory evaluation results, β-damascenone is estimated to be the main aroma-active compound of the essential oil.

  14. Identificationof Major Phenolic Compounds of Chinese Water Chestnut and their Antioxidant Activity

    Directory of Open Access Journals (Sweden)

    Yueming Jiang

    2007-04-01

    Full Text Available Chinese water chestnut (CWC is one of the most popular foods among Asian people due to its special taste and medical function. Experiments were conducted to test the antioxidant activity and then determine the major phenolic compound components present in CWC. CWC phenolic extract strongly inhibited linoleic acid oxidation and exhibited a dose-dependent free-radical scavenging activity against α,α-diphenyl-β-picrylhydrazyl (DPPH radicals, superoxide anions and hydroxyl radicals, which was superior to ascorbic acid and butylated hydroxytoluene (BHT, two commercial used antioxidants. Furthermore, the CWC extract was found to have a relatively higher reducing power, compared with BHT. The major phenolic compounds present in CWC tissues were extracted, purified and identified by high-performance liquid chromatograph (HPLC as (–-gallocatechin gallate, (–-epicatechin gallate and (+-catechin gallate. This study suggests that CWC tissues exhibit great potential for antioxidant activity and may be useful for their nutritional and medicinal functions.

  15. Profiling of volatile organic compounds produced by clinical Aspergillus isolates using gas chromatography-mass spectrometry

    NARCIS (Netherlands)

    Gerritsen, M G; Brinkman, P; Escobar Salazar, Natalia; Bos, L D; de Heer, K; Meijer, M; Janssen, H-G; de Cock, H; Wösten, H A B; Visser, C.E.; van Oers, M H J; Sterk, P J

    Volatile organic compounds (VOCs) in exhaled breath may identify the presence of invasive pulmonary aspergillosis. We aimed to detect VOC profiles emitted by in vitro cultured, clinical Aspergillus isolates using gas chromatography-mass spectrometry (GC-MS). Three clinical Aspergillus isolates and a

  16. Profiling of volatile organic compounds produced by clinical Aspergillus isolates using gas chromatography-mass spectrometry

    NARCIS (Netherlands)

    Gerritsen, M. G.; Brinkman, P.; Escobar, N.; Bos, L. D.; de Heer, K.; Meijer, M.; Janssen, H.-G.; de Cock, H.; Wösten, H. A. B.; Visser, C. E.; van Oers, M. H. J.; Sterk, P. J.

    2018-01-01

    Volatile organic compounds (VOCs) in exhaled breath may identify the presence of invasive pulmonary aspergillosis. We aimed to detect VOC profiles emitted by in vitro cultured, clinical Aspergillus isolates using gas chromatography-mass spectrometry (GC-MS). Three clinical Aspergillus isolates and a

  17. Ultrabroad linewidth orange-emitting nanowires LED for high CRI laser-based white lighting and gigahertz communications

    KAUST Repository

    Janjua, Bilal

    2016-08-10

    Group-III-nitride laser diode (LD)-based solid-state lighting device has been demonstrated to be droop-free compared to light-emitting diodes (LEDs), and highly energy-efficient compared to that of the traditional incandescent and fluorescent white light systems. The YAG:Ce3+ phosphor used in LD-based solid-state lighting, however, is associated with rapid degradation issue. An alternate phosphor/LD architecture, which is capable of sustaining high temperature, high power density, while still intensity- and bandwidth-tunable for high color-quality remained unexplored. In this paper, we present for the first time, the proof-of-concept of the generation of high-quality white light using an InGaN-based orange nanowires (NWs) LED grown on silicon, in conjunction with a blue LD, and in place of the compound-phosphor. By changing the relative intensities of the ultrabroad linewidth orange and narrow-linewidth blue components, our LED/LD device architecture achieved correlated color temperature (CCT) ranging from 3000 K to above 6000K with color rendering index (CRI) values reaching 83.1, a value unsurpassed by the YAG-phosphor/blue-LD counterpart. The white-light wireless communications was implemented using the blue LD through on-off keying (OOK) modulation to obtain a data rate of 1.06 Gbps. We therefore achieved the best of both worlds when orange-emitting NWs LED are utilized as “active-phosphor”, while blue LD is used for both color mixing and optical wireless communications.

  18. Flexible bottom-emitting white organic light-emitting diodes with semitransparent Ni/Ag/Ni anode.

    Science.gov (United States)

    Koo, Ja-Ryong; Lee, Seok Jae; Lee, Ho Won; Lee, Dong Hyung; Yang, Hyung Jin; Kim, Woo Young; Kim, Young Kwan

    2013-05-06

    We fabricated a flexible bottom-emitting white organic light-emitting diode (BEWOLED) with a structure of PET/Ni/Ag/Ni (3/6/3 nm)/ NPB (50 nm)/mCP (10 nm)/7% FIrpic:mCP (10 nm)/3% Ir(pq)(2) acac:TPBi (5 nm)/7% FIrpic:TPBi (5 nm)/TPBi (10 nm)/Liq (2 nm)/ Al (100 nm). To improve the performance of the BEWOLED, a multilayered metal stack anode of Ni/Ag/Ni treated with oxygen plasma for 60 sec was introduced into the OLED devices. The Ni/Ag/Ni anode effectively enhanced the probability of hole-electron recombination due to an efficient hole injection into and charge balance in an emitting layer. By comparing with a reference WOLED using ITO on glass, it is verified that the flexible BEWOLED showed a similar or better electroluminescence (EL) performance.

  19. Influences of wide-angle and multi-beam interference on the chromaticity and efficiency of top-emitting white organic light-emitting diodes

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Lingling; Zhou, Hongwei; Chen, Shufen, E-mail: iamsfchen@njupt.edu.cn; Liu, Bin; Wang, Lianhui [Key Laboratory for Organic Electronics and Information Displays and Institute of Advanced Materials, Nanjing University of Posts and Telecommunications, Nanjing 210023 (China); Shi, Hongying [Jiangsu-Singapore Joint Research Center for Organic/Bio- Electronics and Information Displays and Institute of Advanced Materials, Nanjing Tech University, Nanjing 211816 (China); Huang, Wei, E-mail: iamdirector@njupt.edu.cn [Key Laboratory for Organic Electronics and Information Displays and Institute of Advanced Materials, Nanjing University of Posts and Telecommunications, Nanjing 210023 (China); Jiangsu-Singapore Joint Research Center for Organic/Bio- Electronics and Information Displays and Institute of Advanced Materials, Nanjing Tech University, Nanjing 211816 (China)

    2015-02-28

    Wide-angle interference (WI) and multi-beam interference (MI) in microcavity are analyzed separately to improve chromaticity and efficiency of the top-emitting white organic light-emitting diodes (TWOLEDs). A classic electromagnetic theory is used to calculate the resonance intensities of WI and MI in top-emitting organic light-emitting diodes (TOLEDs) with influence factors (e.g., electrodes and exciton locations) being considered. The role of WI on the performances of TOLEDs is revealed through using δ-doping technology and comparing blue and red EML positions in top-emitting and bottom-emitting devices. The blue light intensity significantly increases and the chromaticity of TWOLEDs is further improved with the use of enhanced WI (the blue emitting layer moving towards the reflective electrode) in the case of a weak MI. In addition, the effect of the thicknesses of light output layer and carrier transport layers on WI and MI are also investigated. Apart from the microcavity effect, other factors, e.g., carrier balance and carrier recombination regions are considered to obtain TWOLEDs with high efficiency and improved chromaticity near white light equal-energy point.

  20. Analysis of the Compounds from the BTEX Group, Emitted During Thermal Decomposition of Alkyd Resin

    Directory of Open Access Journals (Sweden)

    M. Kubecki

    2012-09-01

    Full Text Available Suitability of the given binding agent for the moulding sands preparation depends on the one hand on the estimation of technological properties of the sand and the mould made of it and the obtained casting quality and on the other hand on the assessment of this sand influence on the natural and working environment. Out of moulding sands used in the foundry industry, sands with organic binders deserve a special attention. These binders are based on synthetic resins, which ensure obtaining the proper technological properties and sound castings, however, they negatively influence the environment. If in the initial state these resins are not very dangerous for people and for the environment, thus under an influence of high temperatures they generate very harmful products, being the result of their thermal decomposition. Depending on the kind of the applied resin (phenol-formaldehyde, urea, furfuryl, urea–furfuryl, alkyd under an influence of a temperature such compounds as: furfuryl alcohol, formaldehyde, phenol, BTEX group (benzene, toluene, ethylbenzene, xylene, and also polycyclic aromatic hydrocarbons (PAH can be formed and released.The aim of the study was the development of the method, selection of analytical methods and the determination of optimal conditionsof formation compounds from the BTEX group. An emission of these components constitutes one of the basic criteria of the harmfulnessassessment of binders applied for moulding and core sands. Investigations were carried out in the specially designed set up for the thermal decomposition of organic substances in a temperature range: 5000C – 13000C at the laboratory scale. The object for testing was alkyd resin applied as a binding material for moulding sands. Within investigations the minimal amount of adsorbent necessary for the adsorption of compounds released during the decomposition of the resin sample of a mass app. 15 mg was selected. Also the minimal amount of solvent needed for

  1. RESEARCH REGARDING THE POTENTIAL ACTIVITY OF SOME HETEROCYCLIC COMPOUNDS ON PLANTS GROWTH AND DEVELOPMENT

    Directory of Open Access Journals (Sweden)

    OANA-IRINA PATRICIU

    2017-06-01

    Full Text Available It is well known that growth and morphogenesis of plant tissue cultures can be improved by small amounts of some organic compounds. Heterocyclic compounds such as chromanones and thiazoles derivatives, valuable because of their potential biological activities, have also been reported as pesticides, herbicides and plant-growth regulators. In the present study, different concentrations of chromanones and thiazoles derivatives were employed to evaluate their effects on plantlets growth of Ocimum basilicum L. and Echinacea purpurea L. The studied compounds were proved to be growth inhibitors at high concentrations. A growth stimulation effect was registered at low concentration.

  2. Antioxidant activities of isolated compounds from stems of Mimosa invisa Mart. ex Colla

    Energy Technology Data Exchange (ETDEWEB)

    Aguiar, Rosane M. [Departamento de Quimica e Exatas, Universidade Estadual do Sudoeste da Bahia, Jequie, BA (Brazil); Alves, Clayton Q.; David, Jorge M.; Rezende, Larissa C. de; Lima, Luciano S., E-mail: jmdavid@ufba.br [Instituto de Quimica, Universidade Federal da Bahia, Salvador, BA (Brazil); David, Juceni P. [Faculdade de Farmacia, Universidade Federal da Bahia, Salvador, BA (Brazil); Queiroz, Luciano P. de [Departamento de Ciencias Biologicas, Universidade Estadual de Feira de Santana, BA (Brazil)

    2012-07-01

    This work describes the phytochemical study of stems of Mimosa invisa (Mimosaceae) and the evaluation of the antioxidant potential of isolated compounds. Chromatographic techniques were employed to isolate salicifoliol, pinoresinol, quercetin, quercetin-3-Orhamnopyranosyl, quercetin-3-O-arabinofuranosyl lupeol, -amyrin, sitosterol, p-hydroxy coumaric acid, 4-hydroxy-3-methoxy benzaldehyde (vanillin), 4-hydroxy-3,5-dimethoxy benzaldehyde, 4-hydroxy-3-methoxy benzoic acid and 4',6,7- trimethoxy flavonol. The latter had been previously described but the spectrometric data shown indicated the structure required review. The antioxidant activity of the compounds was evaluated by the DPPH test and capability of NBT reduction by superoxide radicals. Quercetin glycosides showed lower antioxidant potential than quercetin and, salicifoliol was found to be more active than pinoresinol. (author)

  3. Generating nanoparticles containing a new 4-nitrobenzaldehyde thiosemicarbazone compound with antileishmanial activity

    International Nuclear Information System (INIS)

    Aparecida Britta, Elizandra; Conceição da Silva, Cleuza; Forti Rubira, Adley; Vataru Nakamura, Celso; Borsali, Redouane

    2016-01-01

    Thiosemicarbazones are an important class of compounds that have been extensively studied in recent years, mainly because of their broad profile of pharmacological activity. A new 4-nitrobenzaldehyde thiosemicarbazone compound (BZTS) that was derived from S-limonene has been demonstrated to have significant antiprotozoan activity. However, the hydrophobic characteristic of BZTS limits its administration and results in low oral bioavailability. In the present study, we proposed the synthesis of nanoparticle-based block copolymers that can encapsulate BZTS, with morphological evaluation of the nanoparticle suspensions being performed by transmission and cryo-transmission electronic microscopy. The mean particle sizes of the nanoparticle suspensions were determined by static light and dynamic light scattering (SLS/DLS), and the hydrodynamic radius (Rh) was determined using the Stokes-Einstein equation. The zeta potential (ζ) and polydispersity index (PDI) were also determined. The entrapment encapsulation efficiency of the BZTS nanoparticles was measured by ultraviolet spectrophotometry. In vitro activity of BZTS nanoparticle suspensions against intracellular amastigotes of Leishmania amazonensis and cytotoxic activity were also evaluated. The results showed the production of spherical nanoparticles with varied sizes depending on the hydrophobic portion of the amphiphilic diblock copolymers used. Significant concentration-dependent inhibitory activity against intracellular amastigotes was observed, and low cytotoxic activity was demonstrated against macrophages. - Highlights: • The spherical nanoparticles were obtained using distinct diblock copolymers. • BZTS was successfully encapsulated in the nanoparticles. • BZTS nanoparticle suspensions presented activity in Leishmania amazonensis.

  4. Generating nanoparticles containing a new 4-nitrobenzaldehyde thiosemicarbazone compound with antileishmanial activity

    Energy Technology Data Exchange (ETDEWEB)

    Aparecida Britta, Elizandra [Programa de Pós-Graduação em Ciências Farmacêuticas, Universidade Estadual de Maringá (Brazil); Conceição da Silva, Cleuza; Forti Rubira, Adley [Departamento de Química, Universidade Estadual de Maringá (Brazil); Vataru Nakamura, Celso, E-mail: cvnakamura@uem.br [Programa de Pós-Graduação em Ciências Farmacêuticas, Universidade Estadual de Maringá (Brazil); Borsali, Redouane, E-mail: borsali@cermav.cnrs.fr [Centro de Pesquisas em Macromoléculas Vegetais, CERMAV, Grenoble (France)

    2016-12-01

    Thiosemicarbazones are an important class of compounds that have been extensively studied in recent years, mainly because of their broad profile of pharmacological activity. A new 4-nitrobenzaldehyde thiosemicarbazone compound (BZTS) that was derived from S-limonene has been demonstrated to have significant antiprotozoan activity. However, the hydrophobic characteristic of BZTS limits its administration and results in low oral bioavailability. In the present study, we proposed the synthesis of nanoparticle-based block copolymers that can encapsulate BZTS, with morphological evaluation of the nanoparticle suspensions being performed by transmission and cryo-transmission electronic microscopy. The mean particle sizes of the nanoparticle suspensions were determined by static light and dynamic light scattering (SLS/DLS), and the hydrodynamic radius (Rh) was determined using the Stokes-Einstein equation. The zeta potential (ζ) and polydispersity index (PDI) were also determined. The entrapment encapsulation efficiency of the BZTS nanoparticles was measured by ultraviolet spectrophotometry. In vitro activity of BZTS nanoparticle suspensions against intracellular amastigotes of Leishmania amazonensis and cytotoxic activity were also evaluated. The results showed the production of spherical nanoparticles with varied sizes depending on the hydrophobic portion of the amphiphilic diblock copolymers used. Significant concentration-dependent inhibitory activity against intracellular amastigotes was observed, and low cytotoxic activity was demonstrated against macrophages. - Highlights: • The spherical nanoparticles were obtained using distinct diblock copolymers. • BZTS was successfully encapsulated in the nanoparticles. • BZTS nanoparticle suspensions presented activity in Leishmania amazonensis.

  5. Amber light-emitting diode comprising a group III-nitride nanowire active region

    Science.gov (United States)

    Wang, George T.; Li, Qiming; Wierer, Jr., Jonathan J.; Koleske, Daniel

    2014-07-22

    A temperature stable (color and efficiency) III-nitride based amber (585 nm) light-emitting diode is based on a novel hybrid nanowire-planar structure. The arrays of GaN nanowires enable radial InGaN/GaN quantum well LED structures with high indium content and high material quality. The high efficiency and temperature stable direct yellow and red phosphor-free emitters enable high efficiency white LEDs based on the RGYB color-mixing approach.

  6. Microwave assistant synthesis, crystal structure and biological activity of a 1,2,4-triazole compound

    International Nuclear Information System (INIS)

    Ke, W.; Sun, N.B.

    2013-01-01

    The title compound (C/sub 17/H/sub 14/F/sub 2/N/sub 4/SO) were synthesized and recrystallized from CH/sub 3/CN. The compound was characterized by 1h-nmr, ftir, ms, hrms and x-ray diffraction. the compound crystallized in the monoclinic space group c2/c with a = 27.532(6), b 8.9596(18), c 14.609(3) alpha = 90, beta = 112.59(3), lambda =90 degree, gamma = 3327.1(12) alpha 3, z = 8 and r = 0.0327 for 2596 observed reflections with 1 > 2 (i). x-ray analysis reveals that not only intermolecular N-H-N interactions, but also C-H Pie stacking interactions exist in the adjacent molecules. The biological activities results showed that it exhibited significant herbicidal activity towards brassica napus. (author)

  7. Distribution and enzymatic activity of heterotrophic bacteria decomposing selected macromolecular compounds in a Baltic Sea sandy beach

    Science.gov (United States)

    Podgórska, B.; Mudryk, Z. J.

    2003-03-01

    The potential capability to decompose macromolecular compounds, and the level of extracellular enzyme activities were determined in heterotrophic bacteria isolated from a sandy beach in Sopot on the Southern Baltic Sea coast. Individual isolates were capable of hydrolysing a wide spectrum of organic macromolecular compounds. Lipids, gelatine, and DNA were hydrolyzed most efficiently. Only a very small percentage of strains were able to decompose cellulose, and no pectinolytic bacteria were found. Except for starch-hydrolysis, no significant differences in the intensity of organic compound decomposition were recorded between horizontal and vertical profiles of the studied beach. Of all the studied extracellular enzymes, alkaline phosphatase, esterase lipase, and leucine acrylaminidase were most active; in contrast, the activity α-fucosidase, α-galactosidase and β-glucouronidase was the weakest. The level of extracellular enzyme activity was similar in both sand layers.

  8. Determination of Pesticides by Gas Chromatography Combined with Mass Spectrometry Using Femtosecond Lasers Emitting at 267, 400, and 800 nm as the Ionization Source.

    Science.gov (United States)

    Yang, Xixiang; Imasaka, Tomoko; Imasaka, Totaro

    2018-04-03

    A standard sample mixture containing 51 pesticides was separated by gas chromatography (GC), and the constituents were identified by mass spectrometry (MS) using femtosecond lasers emitting at 267, 400, and 800 nm as the ionization source. A two-dimensional display of the GC/MS was successfully used for the determination of these compounds. A molecular ion was observed for 38 of the compounds at 267 nm and for 30 of the compounds at 800 nm, in contrast to 27 among 50 compounds when electron ionization was used. These results suggest that the ultraviolet laser is superior to the near-infrared laser for molecular weight determinations and for a more reliable analysis of these compounds. In order to study the conditions for optimal ionization, the experimental data were examined using the spectral properties (i.e., the excitation and ionization energies and absorption spectra for the neutral and ionized species) obtained by quantum chemical calculations. A few molecules remained unexplained by the currently reported rules, requiring additional rules for developing a full understanding of the femtosecond ionization process. The pesticides in the homogenized matrix obtained from kabosu ( citrus sphaerocarpa) were measured using lasers emitting at 267 and 800 nm. The pesticides were clearly separated and measured on the two-dimensional display, especially for the data measured at 267 nm, suggesting that this technique would have potential for use in the practical trace analysis of the pesticides in the environment.

  9. Novel direct factor Xa inhibitory compounds from Tenebrio molitor with anti-platelet aggregation activity.

    Science.gov (United States)

    Lee, Wonhwa; Kim, Mi-Ae; Park, InWha; Hwang, Jae Sam; Na, MinKyun; Bae, Jong-Sup

    2017-11-01

    Tenebrio molitor is an edible insect that has antimicrobial, anticancer, and antihypertensive effects. The aim of this study was to identify the unreported bioactive compounds from T. molitor larvae with inhibitory activities against factor Xa (FXa) and platelet aggregation. Isolated compounds were evaluated for their anti-FXa and anti-platelet aggregation properties by monitoring clotting time, platelet aggregation, FXa activity, and thrombus formation. A diketopiperazine (1, cyclo( L -Pro- L -Tyr)) and a phenylethanoid (2, N-acetyltyramine) were isolated and inhibited the catalytic activity of FXa in a mixed inhibition model and inhibited platelet aggregation induced by adenosine diphosphate (ADP) and U46619. They inhibited ADP- and U46619-induced phosphorylation of myristoylated alanine-rich C kinase substrate (MARCKS) and the expression of P-selectin and PAC-1 in platelets. They also improved the production of nitric oxide and inhibited the oversecretion of endothelin-1 compared to that of the ADP- or U46619-treated group. In an animal model of arterial and pulmonary thrombosis, the isolated compounds showed enhanced antithrombotic effects. They also elicited anticoagulant effects in mice. Compounds 1-2 inhibited ADP-, collagen-, or U46619-induced platelet aggregation and showed similar anti-thrombotic efficacy to rivaroxaban, a positive control. Therefore, 1-2 could serve as candidates and provide scaffolds for the development of new anti-FXa and anti-platelet drugs. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Light emission from compound eye with conformal fluorescent coating

    Science.gov (United States)

    Martín-Palma, Raúl J.; Miller, Amy E.; Pulsifer, Drew P.; Lakhtakia, Akhlesh

    2015-03-01

    Compound eyes of insects are attractive biological systems for engineered biomimicry as artificial sources of light, given their characteristic wide angular field of view. A blowfly eye was coated with a thin conformal fluorescent film, with the aim of achieving wide field-of-view emission. Experimental results showed that the coated eye emitted visible light and that the intensity showed a weaker angular dependence than a fluorescent thin film deposited on a flat surface.

  11. Compounds Released from Biomass Deconstruction: Understanding Their Effect on Cellulose Enzyme Hydrolysis and Their Biological Activity

    Science.gov (United States)

    Djioleu, Angele Mezindjou

    The effect of compounds produced during biomass pretreatment on cellulolytic enzyme was investigated. Liquid prehydrolyzates were prepared by pretreating switchgrass using 24 combinations of temperature, time, and sulfuric acid concentration based on a full factorial design. Temperature was varied from 140°C to 180°C; time ranged from 10 to 40 min; and the sulfuric acid concentrations were 0.5% or 1% (v/v). Identified products in the prehydrolyzates included xylose, glucose, hydroxymethylfurfural (HMF), furfural, acetic acid, formic acid, and phenolic compounds at concentration ranging from 0 to 21.4 g/L. Pretreatment conditions significantly affected the concentrations of compounds detected in prehydrolyzates. When assayed in the presence of switchgrass prehydrolyzates against model substrates, activities of cellulase, betaglucosidase, and exoglucanase, were significantly reduced by at least 16%, 31.8%, and 57.8%, respectively, as compared to the control. A strong positive correlation between inhibition of betaglucosidase and concentration of glucose, acetic acid, and furans in prehydrolyzate was established. Exoglucanase inhibition correlated with the presence of phenolic compounds and acetic acid. The prehydrolyzate, prepared at 160°C, 30 min, and 1% acid, was fractionated by centrifugal partition chromatography (CPC) into six fractions; the inhibition effect of these fractions on betaglucosidase and exoglucanase was determined. The initial hydrolysis rate of cellobiose by betaglucosidase was significantly reduced by the CPC sugar-rich fraction; however, exoglucanase was deactivated by the CPC phenolic-rich fraction. Finally, biological activities of water-extracted compounds from sweetgum bark and their effect on cellulase was investigated. It was determined that 12% of solid content of the bark extract could be accounted by phenolic compounds with gallic acid identified as the most concentrated phytochemical. Sweetgum bark extract inhibited Staphylococcus

  12. Synthesis, luminescent properties and white light emitting diode application of Ba{sub 7}Zr(PO{sub 4}){sub 6}:Eu{sup 2+} yellow-emitting phosphor

    Energy Technology Data Exchange (ETDEWEB)

    Li, Chenxia; Dai, Jian [College of Optical and Electronic Technology, China Jiliang University, Hangzhou 310018 (China); Deng, Degang, E-mail: dengdegang@cjlu.edu.cn [College of Materials Science and Engineering, China Jiliang University, Hangzhou 310018 (China); Shen, Changyu [College of Optical and Electronic Technology, China Jiliang University, Hangzhou 310018 (China); Xu, Shiqing, E-mail: sxucjlu@163.com [College of Materials Science and Engineering, China Jiliang University, Hangzhou 310018 (China)

    2015-10-15

    A yellow-emitting phosphor, Eu{sup 2+}-activated Ba{sub 7}Zr(PO{sub 4}){sub 6} phosphor was synthesized by solid-state reaction method and the luminescence properties were investigated. The phosphor exhibited strong absorption in near ultraviolet (n-UV) region, which matched well with the n-UV chip. Upon excitation at 370 nm, the Ba{sub 7}Zr(PO{sub 4}){sub 6}:Eu{sup 2+} phosphor has a broad yellow emission band with a peak at 585 nm and a full width at half maximum of 178 nm wider than that of the commercial yellow-emitting YAG:Ce{sup 3+} phosphor. The mechanism of concentration quenching of Eu{sup 2+} ions in Ba{sub 7}Zr(PO{sub 4}){sub 6} phosphor is verified to be energy transfer among the nearest neighbor Eu{sup 2+} ions. The CIE value and temperature dependence of photoluminescence were also discussed. Furthermore, a white-LED was fabricated using a 370 nm UV chip pumped with a blend of phosphors consisting of yellow-emitting Ba{sub 6.97}Zr(PO{sub 4}){sub 6}:0.03Eu{sup 2+} and blue-emitting BaMgAl{sub 10}O{sub 17}:Eu{sup 2+} phosphors, which achieved a CIE of (0.3329, 0.3562) with a color-rendering index of 86.4 around the CCT of 5487 K.

  13. Improvement of carrier transport and luminous efficiency of organic light emitting diodes by introducing a co-deposited active layer

    Energy Technology Data Exchange (ETDEWEB)

    Ohtani, Naoki; Murata, Masaya; Kashiwabara, Keiichiro; Kurata, Kazunori, E-mail: ohtani@mail.doshisha.ac.j [Department of Electronics, Doshisha University, 3-1 Tatara-Miyakodani, Kyotanabe-shi, Kyoto 610-0321 (Japan)

    2009-11-15

    We evaluated carrier transport and luminous efficiency of organic light-emitting diodes (OLEDs) whose active regions consist of a single co-deposited layer. One organic material is a hole transport material N,N'-Bis(3-methylphenyl)-N,N'-diphenylbenzidine (TPD), while the other is an electron transport/emissive material Tris(8-hydroxyquinolinato)-aluminum (Alq3). It was found that the luminous efficiency strongly depends on the thickness and the ratio of the TPD:Alq3 co-deposited layer. This indicates that the carrier balance in the active region can be improved by changing the co-deposited layers. In addition, we performed the dye-doping method to clarify the recombination region. As a result, we found that the radiative recombination is caused in the whole TPD:Alq3 co-deposited layer.

  14. Pharmacological activities and medicinal properties of endemic Moroccan medicinal plant Origanum compactum (Benth and their main compounds

    Directory of Open Access Journals (Sweden)

    Abdelhakim Bouyahya

    2017-10-01

    Full Text Available Oregano [Origanum compactum Benth. (O. compactum, Lamiaceae] is an endemic Moroccan medicinal herb. It is used traditionally to fight against several disorders such as diarrhea, urolithiasis, hypertension, diabetes, and inflammation. A large number of components have been identified and isolated from the essential oil of this plant. Carvacrol, thymol, p-cymene and γ-Terpinene are among the more compounds presented in O. compactum essential oil and considered to be the main biologically active components. Numerous experimental studies showed that O. compactum organic extracts, essentials oil and its main compounds possess a broader spectrum of pharmacological and therapeutic activities such as antibacterial, antifungal, antioxidant, and anticancer activity. The present review attempts to give an overview of pharmacological studies of O. compactum and its major compounds.

  15. Light emitting fabric technologies for photodynamic therapy.

    Science.gov (United States)

    Mordon, Serge; Cochrane, Cédric; Tylcz, Jean Baptiste; Betrouni, Nacim; Mortier, Laurent; Koncar, Vladan

    2015-03-01

    Photodynamic therapy (PDT) is considered to be a promising method for treating various types of cancer. A homogeneous and reproducible illumination during clinical PDT plays a determinant role in preventing under- or over-treatment. The development of flexible light sources would considerably improve the homogeneity of light delivery. The integration of optical fiber into flexible structures could offer an interesting alternative. This paper aims to describe different methods proposed to develop Side Emitting Optical Fibers (SEOF), and how these SEOF can be integrated in a flexible structure to improve light illumination of the skin during PDT. Four main techniques can be described: (i) light blanket integrating side-glowing optical fibers, (ii) light emitting panel composed of SEOF obtained by micro-perforations of the cladding, (iii) embroidery-based light emitting fabric, and (iv) woven-based light emitting fabric. Woven-based light emitting fabrics give the best performances: higher fluence rate, best homogeneity of light delivery, good flexibility. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Volatiles emitted from flowers by gamma-radiated and nonradiated Jasminum polyanthum Franch. in situ

    International Nuclear Information System (INIS)

    Christensen, L.P.; Jakobsen, H.B.; Kristiansen, K.; Moller, J.

    1997-01-01

    Volatile compounds emitted from flowers of Jasminum polyanthum Pepita in situ were collected by dynamic headspace technique and analyzed by GC-FID and GC-MS. A total of 32 compounds were identified. The flower scent was dominated by benzyl acetate (57.8%), p-cresol (12.2%), (E)-isoeugenol (9.7%), eugenol (3.5%), 2-methoxy-p-cresol (3.1%), linalool (3.0%), phenethyl acetate (2.1%), and (Z)3-hexenyl butyrate (1.9%). The strong scent of Pepita reduces its production potentialities as a pot plant, thus the possibility to reduce or modify the emission of volatiles from Pepita by mutagenesis was investigated. The average total yields of volatiles in Pepita were approximately 2800 ng flower-1 h-1, and in one gamma-radiated clone a significantly lower yield of 1050 ng flower-1 h-1 was found. The volatile profiles of the gamma-radiated plants were made up of the same 32 compounds found in Pepita. Significant differences in the headspace composition between Pepita and gamma-radiated plants were found for some of the major volatiles

  17. Structural Characterization and Evaluation of the Antioxidant Activity of Phenolic Compounds from Astragalus taipaishanensis and Their Structure-Activity Relationship

    Science.gov (United States)

    Pu, Wenjun; Wang, Dongmei; Zhou, Dan

    2015-09-01

    Eight phenolic compounds were isolated using bio-guided isolation and purified from the roots of Astragalus taipaishanensis Y. C. Ho et S. B. Ho (A. taipaishanensis) for the first time. Their structures were elucidated by ESI-MS, HR-ESI-MS, 1D-NMR and 2D-NMR as 7,2‧-dihydroxy-3‧,4‧-dimethoxy isoflavan (1), formononetin (2), isoliquiritigenin (3), quercetin (4), kaempferol (5), ononin (6), p-hydroxybenzoic acid (7) and vanillic acid (8). Six flavonoids (compounds 1-6) exhibited stronger antioxidant activities (determined by DPPH, ABTS, FRAP and lipid peroxidation inhibition assays) than those of BHA and TBHQ and also demonstrated noticeable protective effects (particularly quercetin and kaempferol) on Escherichia coli under oxidative stress. Additionally, the chemical constituents compared with those of Astragalus membranaceus and the structure-activity relationship of the isolated compounds were both analyzed. The results clearly demonstrated that A. taipaishanensis has the potential to be selected as an alternative medicinal and food plant that can be utilized in health food products, functional tea and pharmaceutical products.

  18. Highly efficient silicon light emitting diode

    NARCIS (Netherlands)

    Le Minh, P.; Holleman, J.; Wallinga, Hans

    2002-01-01

    In this paper, we describe the fabrication, using standard silicon processing techniques, of silicon light-emitting diodes (LED) that efficiently emit photons with energy around the silicon bandgap. The improved efficiency had been explained by the spatial confinement of charge carriers due to a

  19. Qualitative comparison of active compounds between red and green Mariposa Christia Vespertillonis leaves extracts

    Science.gov (United States)

    Osman, M. S.; Ghani, Z. A.; Ismail, N. F.; Razak, N. A. A.; Jaapar, J.; Ariff, M. A. M.

    2017-09-01

    At present time, Mariposa Christia Vespertillonis (MCV) leave has become popular for its anti-cancer and thus is used widely among the traditional medicine in Malaysia. There are several types of MCV plants and the one that is currently well-known for traditional medicine in Malaysia is the green MCV (GMCV). Red MCV (RMCV) is another type of MCV plant which can also be found easily in Malaysia. In this study, the active compounds for GMCV and RMCV will be compared and analyzed by using Liquid Chromatography - Mass Spectrometry (LC-MS). The active compounds will be extracted from the MCV leaves by using Supercritical Fluid Extraction (SFE). The findings of this study indicates the global yield of the MCV oils is 31 mg/g while the compound identification indicates the presence of anti-cancer, anti-inflammatory and beneficial phytochemicals. This work is an explorative study to reveal the potential of MCV to be extracted using SFE method as potential therapeutic plants for the traditional medicine in Malaysia.

  20. Emission of Biogenic Volatile Organic Compounds in the Arctic

    DEFF Research Database (Denmark)

    Lindwall, Frida

    , emitted in order to communicate within and between trophic levels and as protection against biotic and abiotic stresses, or as byproducts. Some BVOCs are very reactive, and when entering the atmosphere they rapidly react with for example hydroxyl radicals and ozone, affecting the oxidative capacity......Emissions of biogenic volatile organic compounds (BVOCs) from arctic ecosystems are scarcely studied and the effect of climate change on BVOC emissions even less so. BVOCs are emitted from all living organisms and play a role for atmospheric chemistry. The major part of BVOCs derives from plants...... in the atmosphere. This may warm the climate due to a prolonged lifetime of the potent greenhouse gas methane in the atmosphere. However, oxidized BVOCs may participate in formation or growth of aerosols, which in turn may mitigate climate warming. Climate change in the Arctic, an area characterized by short...

  1. Plant compounds insecticide activity against Coleoptera pests of stored products

    OpenAIRE

    MOREIRA, M.D.; PICANÇO, M.C.; BARBOSA, L.C. de A.; GUEDES, R.N.C.; CAMPOS, M.R. de; SILVA, G.A.; MARTINS, J.C.

    2008-01-01

    The objective of this work was to screen plants with insecticide activity, in order to isolate, identify and assess the bioactivity of insecticide compounds present in these plants, against Coleoptera pests of stored products: Oryzaephilus surinamensis L. (Silvanidae), Rhyzopertha dominica F. (Bostrichidae) and Sitophilus zeamais Mots. (Curculionidae). The plant species used were: basil (Ocimum selloi Benth.), rue (Ruta graveolens L.), lion's ear (Leonotis nepetifolia (L.) R.Br.), jimson weed...

  2. Synthesis of novel 3-cyclohexylpropanoic acid-derived nitrogen heterocyclic compounds and their evaluation for tuberculostatic activity.

    Science.gov (United States)

    Gobis, Katarzyna; Foks, Henryk; Bojanowski, Krzysztof; Augustynowicz-Kopeć, Ewa; Napiórkowska, Agnieszka

    2012-01-01

    A series of novel 3-cyclohexylpropanoic acid derivatives and 3-cyclohexylpropanoic acid-derived nitrogen heterocyclic compounds (1-8) have been synthesized and evaluated for tuberculostatic activity. Compounds 1a, 1c, 1e and 1f bearing benzimidazole or benzimidazole-like systems showed the most potent tuberculostatic activity against Mycobacterium tuberculosis strains with MIC values ranging from 1.5 to 12.5μg/mL. More importantly 1a (6-chloro-2-(2-cyclohexylethyl)-4-nitro-1H-benzo[d]imidazole) and 1f (2-(2-cyclohexylethyl)-1H-imidazo[4,5-b]phenazine) appeared selective for M. tuberculosis as compared with eukaryotic cells (human fibroblasts), and other antimicrobial strains. These compounds may thus represent a novel, selective class of antitubercular agents. Additionally compound 1a stimulated type I collagen output by fibroblasts, in vitro. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. Antimicrobial and enhancement of the antibiotic activity by phenolic compounds: Gallic acid, caffeic acid and pyrogallol.

    Science.gov (United States)

    Lima, Valéria N; Oliveira-Tintino, Cícera D M; Santos, Enaide S; Morais, Luís P; Tintino, Saulo R; Freitas, Thiago S; Geraldo, Yuri S; Pereira, Raimundo L S; Cruz, Rafael P; Menezes, Irwin R A; Coutinho, Henrique D M

    2016-10-01

    The indiscriminate use of antimicrobial drugs has increased the spectrum of exposure of these organisms. In our studies, these phenolic compounds were evaluated: gallic acid, caffeic acid and pyrogallol. The antibacterial, antifungal and modulatory of antibiotic activities of these compounds were assayed using microdilution method of Minimum Inhibitory Concentration (MIC) to bacteria and Minimum Fungicide Concentration (MFC) to fungi. The modulation was made by comparisons of the MIC and MFC of the compounds alone and combined with drugs against bacteria and fungi respectively, using a sub-inhibitory concentration of 128 μg/mL of substances (MIC/8). All substances not demonstrated clinically relevant antibacterial activity with a MIC above ≥1024 μg/mL. As a result, we observed that the caffeic acid presented a potentiating antibacterial effect over the 3 groups of bacteria studied. Pyrogallol showed a synergistic effect with two of the antibiotics tested, but only against Staphylococcus aureus. In general, caffeic acid was the substance that presented with the greatest number of antibiotics and with the greatest number of bacteria. In relation to the antifungal activity of all the compounds, the verified results were ≥1024 μg/mL, not demonstrating significant activity. Regarding potentiation of the effect of fluconazole, was observed synergistic effect only when assayed against Candida tropicalis, with all substances. Therefore, as can be seen, the compounds presented as substances that can be promising potentiating agents of antimicrobial drugs, even though they do not have direct antibacterial and antifungal action. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Side-emitting fiber optic position sensor

    Science.gov (United States)

    Weiss, Jonathan D [Albuquerque, NM

    2008-02-12

    A side-emitting fiber optic position sensor and method of determining an unknown position of an object by using the sensor. In one embodiment, a concentrated beam of light source illuminates the side of a side-emitting fiber optic at an unknown axial position along the fiber's length. Some of this side-illuminated light is in-scattered into the fiber and captured. As the captured light is guided down the fiber, its intensity decreases due to loss from side-emission away from the fiber and from bulk absorption within the fiber. By measuring the intensity of light emitted from one (or both) ends of the fiber with a photodetector(s), the axial position of the light source is determined by comparing the photodetector's signal to a calibrated response curve, look-up table, or by using a mathematical model. Alternatively, the side-emitting fiber is illuminated at one end, while a photodetector measures the intensity of light emitted from the side of the fiber, at an unknown position. As the photodetector moves further away from the illuminated end, the detector's signal strength decreases due to loss from side-emission and/or bulk absorption. As before, the detector's signal is correlated to a unique position along the fiber.

  5. Perovskite Materials for Light-Emitting Diodes and Lasers.

    Science.gov (United States)

    Veldhuis, Sjoerd A; Boix, Pablo P; Yantara, Natalia; Li, Mingjie; Sum, Tze Chien; Mathews, Nripan; Mhaisalkar, Subodh G

    2016-08-01

    Organic-inorganic hybrid perovskites have cemented their position as an exceptional class of optoelectronic materials thanks to record photovoltaic efficiencies of 22.1%, as well as promising demonstrations of light-emitting diodes, lasers, and light-emitting transistors. Perovskite materials with photoluminescence quantum yields close to 100% and perovskite light-emitting diodes with external quantum efficiencies of 8% and current efficiencies of 43 cd A(-1) have been achieved. Although perovskite light-emitting devices are yet to become industrially relevant, in merely two years these devices have achieved the brightness and efficiencies that organic light-emitting diodes accomplished in two decades. Further advances will rely decisively on the multitude of compositional, structural variants that enable the formation of lower-dimensionality layered and three-dimensional perovskites, nanostructures, charge-transport materials, and device processing with architectural innovations. Here, the rapid advancements in perovskite light-emitting devices and lasers are reviewed. The key challenges in materials development, device fabrication, operational stability are addressed, and an outlook is presented that will address market viability of perovskite light-emitting devices. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Simple ortho- and para-hydroquinones as compounds neuroprotective against oxidative stress in a manner associated with specific transcriptional activation

    International Nuclear Information System (INIS)

    Satoh, Takumi; Saitoh, Sachie; Hosaka, Manami; Kosaka, Kunio

    2009-01-01

    Electrophilic compounds protect neurons through the activation of the Keap1/Nrf2 pathway and the induction of phase-2 enzymes [T. Satoh, S.A. Lipton, Redox regulation of neuronal survival by electrophilic compounds, Trends Neurosci. 30 (2007) 38-45; T. Satoh, S. Okamoto, J. Cui, Y. Watanabe, K. Furuta, M. Suzuki, K. Tohyama, S.A. Lipton, Activation of the Keap1/Nrf2 pathway for neuroprotection by electrophilic phase II inducers. Proc. Natl. Acad. Sci. USA 103 (2006) 768-773]. Hydroquinone-type electrophilic compounds such as tert-butyl hydroquinone (TBHQ) and carnosic acid (CA) have attracted special attention, because the oxidative conversion of 'hydroquinone' to 'quinone' is essential for the transcriptional activation of the above-mentioned enzymes [T. Satoh, K. Kosaka, K. Itoh, A. Kobayashi, M. Yamamoto, Y. Shimojo, C. Kitajima, J. Cui, J. Kamins, S. Okamoto, T. Shirasawa, S.A. Lipton, Carnosic acid, a catechol-type electrophilic compound, protect neurons both in vitro and in vivo through activation of the Keap1/Nrf2 pathway via S-alkylation of specific cysteine, J. Neurochem. 104 (2008) 1161-1131; A.D. Kraft, D.A. Johnson, J.A. Johnson, Nuclear factor E2-related factor 2-dependent antioxidant response element activation by tert-butylhydroquinone and sulforaphane occurring preferentially in astrocytes conditions neurons against oxidative insult, J. Neurosci. 24 (2004) 1101-1112]. In the present study, we examined the relationship between electrophilicity and the protective effects afforded by electrophilic compounds. Electrophilicity was assessed in terms of the ability of a compound to bind to a cysteine on bovine serum albumin, by which we found that neuroprotective hydroquinones [TBHQ (para-) and CA (ortho-)] had distinctive patterns of cysteine binding compared with other electrophilic compounds. Further, we found that isomers of simple ortho- and para-hydroquinones such as 2-methylhydroquinone (para-) and 4-methyl-catechol (ortho-) [not in abstract] had

  7. Recent Advances in Conjugated Polymers for Light Emitting Devices

    Science.gov (United States)

    AlSalhi, Mohamad Saleh; Alam, Javed; Dass, Lawrence Arockiasamy; Raja, Mohan

    2011-01-01

    A recent advance in the field of light emitting polymers has been the discovery of electroluminescent conjugated polymers, that is, kind of fluorescent polymers that emit light when excited by the flow of an electric current. These new generation fluorescent materials may now challenge the domination by inorganic semiconductor materials of the commercial market in light-emitting devices such as light-emitting diodes (LED) and polymer laser devices. This review provides information on unique properties of conjugated polymers and how they have been optimized to generate these properties. The review is organized in three sections focusing on the major advances in light emitting materials, recent literature survey and understanding the desirable properties as well as modern solid state lighting and displays. Recently, developed conjugated polymers are also functioning as roll-up displays for computers and mobile phones, flexible solar panels for power portable equipment as well as organic light emitting diodes in displays, in which television screens, luminous traffic, information signs, and light-emitting wallpaper in homes are also expected to broaden the use of conjugated polymers as light emitting polymers. The purpose of this review paper is to examine conjugated polymers in light emitting diodes (LEDs) in addition to organic solid state laser. Furthermore, since conjugated polymers have been approved as light-emitting organic materials similar to inorganic semiconductors, it is clear to motivate these organic light-emitting devices (OLEDs) and organic lasers for modern lighting in terms of energy saving ability. In addition, future aspects of conjugated polymers in LEDs were also highlighted in this review. PMID:21673938

  8. Organolead compounds shown to be genetically active

    Energy Technology Data Exchange (ETDEWEB)

    Ahlberg, J; Ramel, C; Wachtmeister, C A

    1972-01-01

    The purpose of the present investigation was to determine whether alkyllead compounds would cause a genetic effect similar to that caused by alkyl mercury compounds. Experiments were conducted on Allium cepa (onion) in order to determine the effect of lead compounds on the spindle fiber mechanism. Results indicate that disturbances of the spindle fiber mechanism occur even at very low concentrations. The lowest concentration at which such effects are observed seems to be between 10/sup -6/ and 10/sup -7/ M for the organic compounds. Although no effect can be observed on the spindle fibers at lower dosages, the mitotic index is changed even at a dose of 10/sup -7/ M with dimethyllead. A preliminary experiment was made on Drosophila with triethyllead in order to investigate whether the effects which were observed on mitoses in Allium would also be observed in a meiotic cell system in an animal.

  9. Anticholinesterase activity of the fluorescent zoanthid pigment, parazoanthoxanthin A.

    Science.gov (United States)

    Sepcić, K; Turk, T; Macek, P

    1998-06-01

    A synthetic linear tetrazacyclopent(f)azulene compound, parazoanthoxanthin A (m.w. 214.2), strongly fluorescent pigment occurring in zoanthids, was characterized and assayed for anticholinesterase activity. The pigment, emitting fluorescence at lambda(em) 420 nm, was found to be a pure competitive inhibitor of cholinesterases. At pH 8.0, a Ki value of 19 and 26 microM was determined with insect recombinant, and electric eel acetylcholinesterase. Horse serum butyrylcholinesterase was less sensitive with a Ki of 70 microM.

  10. Polymer Light-Emitting Diodes Efficiency Dependence on Bipolar Charge Traps Concentration

    Directory of Open Access Journals (Sweden)

    Luis Morgado

    2009-01-01

    Full Text Available The efficiency of light-emitting diodes (LEDs based on poly[(9,9-dioctylfluorenyl-2,7-diyl-alt-1,4-benzo-{2,1′-3}-thiadiazole], F8BT, is optimized upon simultaneous doping with a hole and an electron trapping molecule, namely, N,N′-Bis(3-methylphenyl-N,N′-diphenylbenzidine and 2-(4-biphenylyl-5-(4-tert-butylphenyl-1,3,4-oxadiazole, respectively. It is shown that, for devices with poly(3,4-ethylene dioxythiophene doped with polystyrene sulfonic acid as hole-injection layer material and magnesium cathodes, the efficiency is nearly doubled (from ca. 2.5 to 3.7 cd/A upon doping with ca. 0.34% by weight of both compounds.

  11. 3.4-Inch Quarter High Definition Flexible Active Matrix Organic Light Emitting Display with Oxide Thin Film Transistor

    Science.gov (United States)

    Hatano, Kaoru; Chida, Akihiro; Okano, Tatsuya; Sugisawa, Nozomu; Inoue, Tatsunori; Seo, Satoshi; Suzuki, Kunihiko; Oikawa, Yoshiaki; Miyake, Hiroyuki; Koyama, Jun; Yamazaki, Shunpei; Eguchi, Shingo; Katayama, Masahiro; Sakakura, Masayuki

    2011-03-01

    In this paper, we report a 3.4-in. flexible active matrix organic light emitting display (AMOLED) display with remarkably high definition (quarter high definition: QHD) in which oxide thin film transistors (TFTs) are used. We have developed a transfer technology in which a TFT array formed on a glass substrate is separated from the substrate by physical force and then attached to a flexible plastic substrate. Unlike a normal process in which a TFT array is directly fabricated on a thin plastic substrate, our transfer technology permits a high integration of high performance TFTs, such as low-temperature polycrystalline silicon TFTs (LTPS TFTs) and oxide TFTs, on a plastic substrate, because a flat, rigid, and thermally-stable glass substrate can be used in the TFT fabrication process in our transfer technology. As a result, this technology realized an oxide TFT array for an AMOLED on a plastic substrate. Furthermore, in order to achieve a high-definition AMOLED, color filters were incorporated in the TFT array and a white organic light-emitting diode (OLED) was combined. One of the features of this device is that the whole body of the device can be bent freely because a source driver and a gate driver can be integrated on the substrate due to the high mobility of an oxide TFT. This feature means “true” flexibility.

  12. Mass size distribution of particles emitted by diesel engines and determination of the contribution of diesel particles to the atmospheric aerosol in Vienna by using a tracer suitable for activation analysis

    International Nuclear Information System (INIS)

    Norek, C.

    1985-01-01

    In Vienna a large fraction of light absorbing aerosols has been found. The traffic could be a source for the high absorption coefficients, since the time dependent absorption coefficients varise similar to the traffic densities. Diesel vehicles have high soot emissions, so they may contribute considerably to light absorption during the summer. The emission factors of the vehicles were estimated by measurements at different motor and driving conditions by the Constant-Volume-Sampling-Method. To determine the size distributions a 10-stage-low pressure impactor with a lower cut size of 0.015 μm aerodynamic particle diameter was used. In order to estimate the contribution of diesel vehicles to the total mass concentrations all diesel fuel sold in Vienna and its vincinity was marked with an organic Dysprosium compound. This rare earth tracer was emitted by vehicles together with the soot particles and collected at eleven stations in Vienna. The filter samples were extracted with diluted HNO 3 and the extraction was analysed for Dy by neutron activation analysis. The mass size distributions of the particles and the soot emitted from diesel engines are only slightly influenced by motor and driving parameters. The total mass emissions showed considerable variations, but the mean emission factor obtained from the tests was 2.43 g per litre fuel; knowing also the concentration of the tracer in the fuel, the contribution of diesel particles to the mass of the suspended particulates could be estimated. During the measuring period the contribution was c. 25% to the total mass and c. 40% to the absorbing matter in the atmosphere. (Author)

  13. Biogas pre-upgrading by adsorption of trace compounds onto granular activated carbons and an activated carbon fiber-cloth.

    Science.gov (United States)

    Boulinguiez, B; Le Cloirec, P

    2009-01-01

    The study assesses the adsorption onto activated carbon materials of selected volatile organic compounds -VOCs- (dichloromethane, 2-propanol, toluene, siloxane D4) in a biogas matrix composed of methane and carbon dioxide (55:45 v/v). Three different adsorbents are tested, two of them are granular activated carbon (GAC), and the last is an activated carbon fiber-cloth (ACFC). The adsorption isotherm data are fitted by different models by nonlinear regression. The Langmuir-Freundlich model appears to be the adequate one to describe the adsorption phenomena independently of the VOC considered or the adsorbent. The adsorbents present attractive adsorption capacity of the undesirable compounds in biogas atmosphere though the maximum adsorption capacities for a VOC are quite different from each other. The adsorption kinetics are characterized through three coefficients: the initial adsorption coefficient, the external film mass transfer coefficient and the internal diffusion coefficient of Weber. The ACFC demonstrates advanced kinetic yields compared to the granular activated carbon materials whatever VOC is considered. Therefore, pre-upgrading of biogas produced from wastewater sludge or co-digestion system by adsorption onto activated carbon appears worth investigating. Especially with ACFC material that presents correct adsorption capacities toward VOCs and concrete regeneration process opportunity to realize such process.

  14. Characterisation of commercial aromatised vinegars: phenolic compounds, volatile composition and antioxidant activity.

    Science.gov (United States)

    Cejudo-Bastante, María J; Durán-Guerrero, Enrique; Natera-Marín, Ramón; Castro-Mejías, Remedios; García-Barroso, Carmelo

    2013-04-01

    Nineteen commercially available aromatised vinegars, which were representative of this type of product, were tested to ascertain their phenolic and volatile composition and antioxidant activity. The aromatised vinegars came from different raw materials such as fruits, spices, herbs and vegetables. The antioxidant activity was determined by means of photochemiluminescence, phenolic profile by using ultra performance liquid chromatography with ultraviolet detection, and the volatile composition was determined by using stir bar sorptive extraction-gas chromatography-mass spectrometry. Nine polyphenolic compounds and 141 volatile compounds were identified. Vinegar aromatised with black truffle and rosemary obtained the highest values of antioxidant activity, followed by those aromatised with lemon, tarragon, aromatic herbs and vegetables. Antioxidant activity was highly correlated with the presence of trans-p-coutaric acid, trans-caftaric acid, 5-hydroxy-methylfurfural and furfural. Moreover, (Z)-3-hexen-1-ol was exclusive to the vinegar aromatised with tarragon, while p-menth-1,8-ol, dimethyl styrene, 4-methyl acetophenone and nootkatone were only found in vinegar aromatised with lemon. On the basis of the results from the cluster analysis of cases, it can be concluded that the grouping responds more to the trademark of each vinegar than to the raw material. © 2012 Society of Chemical Industry.

  15. Electrically pumped edge-emitting photonic bandgap semiconductor laser

    Science.gov (United States)

    Lin, Shawn-Yu; Zubrzycki, Walter J.

    2004-01-06

    A highly efficient, electrically pumped edge-emitting semiconductor laser based on a one- or two-dimensional photonic bandgap (PBG) structure is described. The laser optical cavity is formed using a pair of PBG mirrors operating in the photonic band gap regime. Transverse confinement is achieved by surrounding an active semiconductor layer of high refractive index with lower-index cladding layers. The cladding layers can be electrically insulating in the passive PBG mirror and waveguide regions with a small conducting aperture for efficient channeling of the injection pump current into the active region. The active layer can comprise a quantum well structure. The quantum well structure can be relaxed in the passive regions to provide efficient extraction of laser light from the active region.

  16. Characterization of Active Compounds of Different Garlic (Allium sativum L. Cultivars

    Directory of Open Access Journals (Sweden)

    Szychowski Konrad A.

    2018-03-01

    Full Text Available Garlic (Allium sativum L. has a reputation as a therapeutic agent for many different diseases such as microbial infections, hypertension, hypercholesterolaemia, diabetes, atherosclerosis and cancer. Health benefits of garlic depend on its content of biologically-active compounds, which differs between cultivars and geographical regions. The aim of this study was to evaluate and compare the biological activity of aqueous extracts from nine garlic varieties from different countries (Poland, Spain, China, Portugal, Burma, Thailand and Uzbekistan. Antioxidant properties were evaluated through free radical scavenging (DPPH•, ABTS•+ and ion chelation (Fe2+, Cu2+ activities. The cytotoxicity of garlic extracts was evaluated in vitro using Neutral Red Uptake assay in normal human skin fibroblasts. The obtained results revealed that garlic extracts contained the highest amount of syringic and p-hydroxybenzoic acids derivatives. The lowest IC50 values for DPPH•, ABTS•+ scavenging and Cu2+ chelating ability were determined in Chinese garlic extracts (4.63, 0.43 and 14.90 μg/mL, respectively. Extracts from Spanish cultivar Morado and Chinese garlic were highly cytotoxic to human skin fibroblasts as they reduced cellular proliferation by 70–90%. We showed diverse contents of proteins and phenolic components in garlic bulbs from different varieties. The obtained results could help to choose the cultivars of garlic which contain significant amounts of active compounds, have important antioxidant properties and display low antiproliferative effect and/or low cytotoxicity against normal human skin fibroblast BJ.

  17. Elicitor Mixtures Significantly Increase Bioactive Compounds, Antioxidant Activity, and Quality Parameters in Sweet Bell Pepper

    Directory of Open Access Journals (Sweden)

    Lina Garcia-Mier

    2015-01-01

    Full Text Available Sweet bell peppers are greatly appreciated for their taste, color, pungency, and aroma. Additionally, they are good sources of bioactive compounds with antioxidant activity, which can be improved by the use of elicitors. Elicitors act as metabolite-inducing factors (MIF by mimic stress conditions. Since plants rarely experience a single stress condition one by one but are more likely to be exposed to simultaneous stresses, it is important to evaluate the effect of elicitors on plant secondary metabolism as mixtures. Jasmonic acid (JA, hydrogen peroxide (HP, and chitosan (CH were applied to fruits and plants of bell pepper as mixtures. Bioactive compounds, antioxidant activity, and quality parameters were evaluated. The assessed elicitor cocktail leads to an increase in the variables evaluated (P ≤ 0.05 when applied to mature fruits after harvest, whereas the lowest values were observed in the treatment applied to immature fruits. Therefore, the application of the elicitor cocktail to harvested mature fruits is recommended in order to improve bioactive compounds and the antioxidant activity of sweet bell peppers.

  18. Identification of the functional binding pocket for compounds targeting small-conductance Ca²⁺-activated potassium channels.

    Science.gov (United States)

    Zhang, Miao; Pascal, John M; Schumann, Marcel; Armen, Roger S; Zhang, Ji-Fang

    2012-01-01

    Small- and intermediate-conductance Ca(2+)-activated potassium channels, activated by Ca(2+)-bound calmodulin, have an important role in regulating membrane excitability. These channels are also linked to clinical abnormalities. A tremendous amount of effort has been devoted to developing small molecule compounds targeting these channels. However, these compounds often suffer from low potency and lack of selectivity, hindering their potential for clinical use. A key contributing factor is the lack of knowledge of the binding site(s) for these compounds. Here we demonstrate by X-ray crystallography that the binding pocket for the compounds of the 1-ethyl-2-benzimidazolinone (1-EBIO) class is located at the calmodulin-channel interface. We show that, based on structure data and molecular docking, mutations of the channel can effectively change the potency of these compounds. Our results provide insight into the molecular nature of the binding pocket and its contribution to the potency and selectivity of the compounds of the 1-EBIO class.

  19. Fatty acid composition of intramuscular fat and odour-active compounds of lamb commercialized in northern Spain.

    Science.gov (United States)

    Bravo-Lamas, Leire; Barron, Luis J R; Farmer, Linda; Aldai, Noelia

    2018-05-01

    Muscle fatty acid composition and odour-active compounds released during cooking were characterized in lamb chops (Longissimus thoracis et lumborum, n = 48) collected at retail level in northern Spain. Lamb samples were classified in two groups according to their 10 t/11 t-18:1 ratio: ≤1 (10 t-non-shifted, n = 21) and >1 (10 t-shifted, n = 27). Higher n-3 polyunsaturated fatty acid, vaccenic (11 t-18:1) and rumenic acid (9c,11 t-18:2), and iso-branched chain fatty acid contents were found in non-shifted lamb samples while n-6 polyunsaturated fatty acid, internal methyl-branched chain fatty acid, and 10 t-18:1 contents were greater in shifted samples. Regardless the fatty acid profile differences between lamb sample groups, odour-active compound profile was very similar and mostly affected by the cooking conditions. Overall, the main odour-active compounds of cooked lamb were described as "green", "meaty", "roasted", and "fatty" being methyl pyrazine, methional, dimethyl pyrazine, and dimethyl trisulphide the main odour-active compounds. Aldehydes and alcohols were the most abundant volatiles in all samples, and they were mostly originated from the oxidation of unsaturated fatty acids during cooking. Copyright © 2018 Elsevier Ltd. All rights reserved.

  20. Semivolatile organic compound emissions from heavy-duty trucks operating on diesel and bio-diesel fuel blends

    Science.gov (United States)

    This study measured semivolatile organic compounds (SVOCs) in particle matter (PM) emitted from three heavy-duty trucks equipped with modern after-treatment technologies. Emissions testing was conducted as described by the George et al. VOC study also presented as part of this se...

  1. Synthesis of morpholine derivatives and Bunte's salt as compounds of potential radioprotective activity

    Energy Technology Data Exchange (ETDEWEB)

    Strzelczyk, M.; Kucharski, A. (Wojskowa Akademia Medyczna, Lodz (Poland))

    1980-01-01

    The purpose of the present study was to obtain several compounds possessing radioprotective activity. The syntheses yielded seven undescribed compounds i.e.: benzyl ester of the N-morpholinecarbathionothioglicol acid, ester bis S-(morpholine-4-thiocarbonyl)-2-thioethyl, morpholine salt of the N-morpholinecarbothionothiolic acid, sodium and potassium salt of S-morpholine-4-carbonyl, methylthiosulfate, sodium and potassium salt of beta-hydroxyethyl thiosulfate. Moreover, with the aid of other methods following compounds were synthetized: beta-S-(morpholine-4-thiocarbonyl) ethyl thiopropioniane, amide of the S-(morpholine-4-thiocarbonyl)-thioglicol acid, acid S-(morpholine-4-thiocarbonyl)-thioglicol acid, sodium salt of the S-(morpholine-4-thiocarbonyl)-thioglicol acid. The structure of these compounds was confirmed using elementary and spectral analysis.

  2. Highly Selective Volatile Organic Compounds Breath Analysis Using a Broadly-Tunable Vertical-External-Cavity Surface-Emitting Laser.

    Science.gov (United States)

    Tuzson, Béla; Jágerská, Jana; Looser, Herbert; Graf, Manuel; Felder, Ferdinand; Fill, Matthias; Tappy, Luc; Emmenegger, Lukas

    2017-06-20

    A broadly tunable mid-infrared vertical-external-cavity surface-emitting laser (VECSEL) is employed in a direct absorption laser spectroscopic setup to measure breath acetone. The large wavelength coverage of more than 30 cm -1 at 3.38 μm allows, in addition to acetone, the simultaneous measurement of isoprene, ethanol, methanol, methane, and water. Despite the severe spectral interferences from water and alcohols, an unambiguous determination of acetone is demonstrated with a precision of 13 ppbv that is achieved after 5 min averaging at typical breath mean acetone levels in synthetic gas samples mimicking human breath.

  3. Antiproliferative and cell apoptosis-inducing activities of compounds from Buddleja davidii in Mgc-803 cells

    Directory of Open Access Journals (Sweden)

    Wu Jian

    2012-08-01

    Full Text Available Abstract Background Buddleja davidii is widely distributed in the southwestern region of China. We have undertaken a systematic analysis of B. davidii as a Chinese traditional medicine with anticancer activity by isolating natural products for their activity against the human gastric cancer cell line Mgc-803 and the human breast cancer cell line Bcap-37. Results Ten compounds were extracted and isolated from B. davidii, among which colchicine was identified in B. davidii for the first time. The inhibitory activities of these compounds were investigated in Mgc-803, Bcap-37 cells in vitro by MTT [3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide] assay, and the results showed that luteolin and colchicine had potent inhibitory activities against the growth of Mgc-803 cells. Subsequent fluorescence staining and flow cytometry analysis indicated that these two compounds could induce apoptosis in Mgc-803 cells. The results also showed that the percentages of early apoptotic cells (Annexin V+/PI-, where PI is propidium iodide and late apoptotic cells (Annexin V+/PI+ increased in a dose- and time-dependent manner. After 36 h of incubation with luteolin at 20 μM, the percentages of cells were approximately 15.4% in early apoptosis and 43.7% in late apoptosis; after 36 h of incubation with colchicine at 20 μM, the corresponding values were 7.7% and 35.2%, respectively. Conclusions Colchicine and luteolin from B. davidii have potential applications as adjuvant therapies for treating human carcinoma cells. These compounds could also induce apoptosis in tumor cells.

  4. Antiproliferative and cell apoptosis-inducing activities of compounds from Buddleja davidii in Mgc-803 cells.

    Science.gov (United States)

    Wu, Jian; Yi, Wenshi; Jin, Linhong; Hu, Deyu; Song, Baoan

    2012-08-31

    Buddleja davidii is widely distributed in the southwestern region of China. We have undertaken a systematic analysis of B. davidii as a Chinese traditional medicine with anticancer activity by isolating natural products for their activity against the human gastric cancer cell line Mgc-803 and the human breast cancer cell line Bcap-37. Ten compounds were extracted and isolated from B. davidii, among which colchicine was identified in B. davidii for the first time. The inhibitory activities of these compounds were investigated in Mgc-803, Bcap-37 cells in vitro by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay, and the results showed that luteolin and colchicine had potent inhibitory activities against the growth of Mgc-803 cells. Subsequent fluorescence staining and flow cytometry analysis indicated that these two compounds could induce apoptosis in Mgc-803 cells. The results also showed that the percentages of early apoptotic cells (Annexin V+/PI-, where PI is propidium iodide) and late apoptotic cells (Annexin V+/PI+) increased in a dose- and time-dependent manner. After 36 h of incubation with luteolin at 20 μM, the percentages of cells were approximately 15.4% in early apoptosis and 43.7% in late apoptosis; after 36 h of incubation with colchicine at 20 μM, the corresponding values were 7.7% and 35.2%, respectively. Colchicine and luteolin from B. davidii have potential applications as adjuvant therapies for treating human carcinoma cells. These compounds could also induce apoptosis in tumor cells.

  5. Synthesis, crystal structure, and photoluminescence of a lithium isothiocyanate compound with 18-crown-6

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Shan; Fu, Bo; Zhao, Zhen; Liu, Xi [Chongqing Normal Univ. (China). Chongqing Key Lab. of Inorganic Functional Materials

    2018-04-01

    The investigation of the supramolecular interactions between the lithium isothiocyanate salt and 18-crown-6 (18C-6) in commercial tetrahydrofuran leads to the formation of a lithium compound, LiNCS(H{sub 2}O)(18C-6) (1). In the crystal structure the asymmetric unit contains two similar LiNCS(H{sub 2}O)(18C-6) molecules. Solid-state photoluminescence experiments have shown that compound 1 emits violet luminescence, and its possible emission mechanism was investigated in detail based on theoretical calculations.

  6. Assessment of rosehips based on the content of their biologically active compounds

    Czech Academy of Sciences Publication Activity Database

    Bhave, A.; Schulzová, V.; Chmelařová, H.; Mrnka, Libor; Hajslová, J.

    2017-01-01

    Roč. 25, č. 2 (2017), s. 681-690 ISSN 1021-9498 R&D Projects: GA TA ČR TE01020080 Institutional support: RVO:67985939 Keywords : rosehips * bioactive compounds * antioxidative activity Subject RIV: EF - Botanics OBOR OECD: Plant sciences, botany Impact factor: 3.048, year: 2016

  7. Characterization of odor-active compounds in cooked meat of farmed obscure puffer (Takifugu obscurus using gas chromatography–mass spectrometry–olfactometry

    Directory of Open Access Journals (Sweden)

    Ning-Ping Tao

    2014-12-01

    Full Text Available The volatile and odor-active compounds in cooked meat of farmed obscure puffer (Takifugu obscurus were analyzed by gas chromatography–mass spectrometry–olfactometry (GC–MS–O. The volatile compounds were extracted by the simultaneous distillation–extraction (SDE method, then separated and identified by GC–MS. Odor-active compounds in the SDE extract were characterized by GC–MS–O. A total of 68 volatile compounds were found, including 23 aldehydes, 10 alcohols, nine ketones, 17 N- or S-containing compounds and aromatics, three acids, three alkanes, and three esters. Of these, 31 odor-active compounds were detected and identified. Trimethylamine (fishy, octanal (grassy, leafy, green, (E-2-octenal (roast, fatty, 1-octen-3-ol (fishy, fatty, mushroom, grassy, 2-ethyl-1-hexanethiol (cooked fish, (E,E-2,4-octadienal (cooked meat, sweet, 2-acetylthiazole (meaty, roast, nutty, sulfur, 2-acetylpyrrole (nutty, walnut, bread were identified as the key odorants in the cooked meat of farmed obscure puffer based on posterior intensity and time-intensity methods.

  8. Broadband mid-infrared superlattice light-emitting diodes

    Science.gov (United States)

    Ricker, R. J.; Provence, S. R.; Norton, D. T.; Boggess, T. F.; Prineas, J. P.

    2017-05-01

    InAs/GaSb type-II superlattice light-emitting diodes were fabricated to form a device that provides emission over the entire 3-5 μm mid-infrared transmission window. Variable bandgap emission regions were coupled together using tunnel junctions to emit at peak wavelengths of 3.3 μm, 3.5 μm, 3.7 μm, 3.9 μm, 4.1 μm, 4.4 μm, 4.7 μm, and 5.0 μm. Cascading the structure recycles the electrons in each emission region to emit several wavelengths simultaneously. At high current densities, the light-emitting diode spectra broadened into a continuous, broadband spectrum that covered the entire mid-infrared band. When cooled to 77 K, radiances of over 1 W/cm2 sr were achieved, demonstrating apparent temperatures above 1000 K over the 3-5 μm band. InAs/GaSb type-II superlattices are capable of emitting from 3 μm to 30 μm, and the device design can be expanded to include longer emission wavelengths.

  9. Effects of emitted electron temperature on the plasma sheath

    International Nuclear Information System (INIS)

    Sheehan, J. P.; Kaganovich, I. D.; Wang, H.; Raitses, Y.; Sydorenko, D.; Hershkowitz, N.

    2014-01-01

    It has long been known that electron emission from a surface significantly affects the sheath surrounding that surface. Typical fluid theory of a planar sheath with emitted electrons assumes that the plasma electrons follow the Boltzmann relation and the emitted electrons are emitted with zero energy and predicts a potential drop of 1.03T e /e across the sheath in the floating condition. By considering the modified velocity distribution function caused by plasma electrons lost to the wall and the half-Maxwellian distribution of the emitted electrons, it is shown that ratio of plasma electron temperature to emitted electron temperature significantly affects the sheath potential when the plasma electron temperature is within an order of magnitude of the emitted electron temperature. When the plasma electron temperature equals the emitted electron temperature the emissive sheath potential goes to zero. One dimensional particle-in-cell simulations corroborate the predictions made by this theory. The effects of the addition of a monoenergetic electron beam to the Maxwellian plasma electrons were explored, showing that the emissive sheath potential is close to the beam energy only when the emitted electron flux is less than the beam flux

  10. HPLC-QTOF-MS method for quantitative determination of active compounds in an anti-cellulite herbal compress

    Directory of Open Access Journals (Sweden)

    Ngamrayu Ngamdokmai

    2017-08-01

    Full Text Available A herbal compress used in Thai massage has been modified for use in cellulite treatment. Its main active ingredients were ginger, black pepper, java long pepper, tea and coffee. The objective of this study was to develop and validate an HPLCQTOF-MS method for determining its active compounds, i.e., caffeine, 6-gingerol, and piperine in raw materials as well as in the formulation together with the flavouring agent, camphor. The four compounds were chromatographically separated. The analytical method was validated through selectivity, intra-, inter day precision, accuracy and matrix effect. The results showed that the herbal compress contained caffeine (2.16 mg/g, camphor (106.15 mg/g, 6-gingerol (0.76 mg/g, and piperine (4.19 mg/g. The chemical stability study revealed that herbal compresses retained >80% of their active compounds after 1 month of storage at ambient conditions. Our method can be used for quality control of the herbal compress and its raw materials.

  11. Characterization of Odorant Compounds from Mechanical Aerated Pile Composting and Static Aerated Pile Composting.

    Science.gov (United States)

    Kumari, Priyanka; Lee, Joonhee; Choi, Hong-Lim

    2016-04-01

    We studied airborne contaminants (airborne particulates and odorous compounds) emitted from compost facilities in South Korea. There are primarily two different types of composting systems operating in Korean farms, namely mechanical aerated pile composting (MAPC) and aerated static pile composting (SAPC). In this study, we analyzed various particulate matters (PM10, PM7, PM2.5, PM1, and total suspended particles), volatile organic compounds and ammonia, and correlated these airborne contaminants with microclimatic parameters, i.e., temperature and relative humidity. Most of the analyzed airborne particulates (PM7, PM2.5, and PM1) were detected in high concentration at SAPC facilities compered to MAPC; however these differences were statistically non-significant. Similarly, most of the odorants did not vary significantly between MAPC and SAPC facilities, except for dimethyl sulfide (DMS) and skatole. DMS concentrations were significantly higher in MAPC facilities, whereas skatole concentrations were significantly higher in SAPC facilities. The microclimate variables also did not vary significantly between MAPC and SAPC facilities, and did not correlate significantly with most of the airborne particles and odorous compounds, suggesting that microclimate variables did not influence their emission from compost facilities. These findings provide insight into the airborne contaminants that are emitted from compost facilities and the two different types of composting agitation systems.

  12. The formation of ultra-fine particles during ozone-initiated oxidations with terpenes emitted from natural paint

    International Nuclear Information System (INIS)

    Lamorena, Rheo B.; Jung, Sang-Guen; Bae, Gwi-Nam; Lee, Woojin

    2007-01-01

    The formation of secondary products during the ozone-initiated oxidations with biogenic VOCs emitted from natural paint was investigated in this study. Mass spectrometry and infrared spectroscopy measurements have shown that the major components of gas-phase chemicals emitted from natural paint are monoterpenes including α- and β-pinenes, camphene, p-cymene, and limonene. A significant formation of gaseous carbonyl products and nano-sized particles (4.4-168 nm) was observed in the presence of ozone. Carboxylic acids were also observed to form during the reactions (i.e. formic acid at 0.170 ppm and acetic acid at 0.260 ppm). The formation of particles increased as the volume of paint introduced into a reaction chamber increased. A secondary increase in the particle number concentration was observed after 440 min, which suggests further partitioning of oxidation products (i.e. carboxylic acids) into the particles previously existing in the reaction chamber. The growth of particles increased as the mean particle diameter and particle mass concentrations increased during the reaction. The experimental results obtained in this study may provide insight into the potential exposure of occupants to irritating chemical compounds formed during the oxidations of biogenic VOCs emitted from natural paint in indoor environments

  13. Kinetic and Isotherm Modelling of the Adsorption of Phenolic Compounds from Olive Mill Wastewater onto Activated Carbon

    Directory of Open Access Journals (Sweden)

    Alessandro A. Casazza

    2015-01-01

    Full Text Available The adsorption of phenolic compounds from olive oil wastewater by commercial activated carbon was studied as a function of adsorbent quantity and temperature. The sorption kinetics and the equilibrium isotherms were evaluated. Under optimum conditions (8 g of activated carbon per 100 mL, the maximum sorption capacity of activated carbon expressed as mg of caff eic acid equivalent per g of activated carbon was 35.8 at 10 °C, 35.4 at 25 °C and 36.1 at 40 °C. The pseudo-second-order model was considered as the most suitable for kinetic results, and Langmuir isotherm was chosen to bett er describe the sorption system. The results confi rmed the effi ciency of activated carbon to remove almost all phenolic compound fractions from olive mill effl uent. The preliminary results obtained will be used in future studies. The carbohydrate fraction of this upgraded residue could be employed to produce bioethanol, and adsorbed phenolic compounds can be recovered and used in different industries.

  14. Irreversible adsorption of phenolic compounds by activated carbons

    Energy Technology Data Exchange (ETDEWEB)

    Grant, T.M.; King, C.J.

    1988-12-01

    Studies were undertaken to determine the reasons why phenolic sorbates can be difficult to remove and recover from activated carbons. The chemical properties of the sorbate and the adsorbent surface, and the influences of changes in the adsorption and desorption conditions were investigated. Comparison of isotherms established after different contact times or at different temperatures indicated that phenolic compounds react on carbon surfaces. The reaction rate is a strong function of temperature. Regeneration of carbons by leaching with acetone recovered at least as much phenol as did regeneration with other solvents or with displacers. The physiochemical properties of adsorbents influences irreversible uptakes. Sorbates differed markedly in their tendencies to undergo irreversible adsorption. 64 refs., 47 figs., 32 tabs.

  15. Irreversible adsorption of phenolic compounds by activated carbons

    International Nuclear Information System (INIS)

    Grant, T.M.; King, C.J.

    1988-12-01

    Studies were undertaken to determine the reasons why phenolic sorbates can be difficult to remove and recover from activated carbons. The chemical properties of the sorbate and the adsorbent surface, and the influences of changes in the adsorption and desorption conditions were investigated. Comparison of isotherms established after different contact times or at different temperatures indicated that phenolic compounds react on carbon surfaces. The reaction rate is a strong function of temperature. Regeneration of carbons by leaching with acetone recovered at least as much phenol as did regeneration with other solvents or with displacers. The physiochemical properties of adsorbents influences irreversible uptakes. Sorbates differed markedly in their tendencies to undergo irreversible adsorption. 64 refs., 47 figs., 32 tabs

  16. Compounds from silicones alter enzyme activity in curing barnacle glue and model enzymes.

    Science.gov (United States)

    Rittschof, Daniel; Orihuela, Beatriz; Harder, Tilmann; Stafslien, Shane; Chisholm, Bret; Dickinson, Gary H

    2011-02-17

    Attachment strength of fouling organisms on silicone coatings is low. We hypothesized that low attachment strength on silicones is, in part, due to the interaction of surface available components with natural glues. Components could alter curing of glues through bulk changes or specifically through altered enzyme activity. GC-MS analysis of silicone coatings showed surface-available siloxanes when the coatings were gently rubbed with a cotton swab for 15 seconds or given a 30 second rinse with methanol. Mixtures of compounds were found on 2 commercial and 8 model silicone coatings. The hypothesis that silicone components alter glue curing enzymes was tested with curing barnacle glue and with commercial enzymes. In our model, barnacle glue curing involves trypsin-like serine protease(s), which activate enzymes and structural proteins, and a transglutaminase which cross-links glue proteins. Transglutaminase activity was significantly altered upon exposure of curing glue from individual barnacles to silicone eluates. Activity of purified trypsin and, to a greater extent, transglutaminase was significantly altered by relevant concentrations of silicone polymer constituents. Surface-associated silicone compounds can disrupt glue curing and alter enzyme properties. Altered curing of natural glues has potential in fouling management.

  17. Occurrence and removal of pharmaceutically active compounds in sewage treatment plants with different technologies

    Science.gov (United States)

    Ying, Guang-Guo; Kookana, Rai S.; Kolpin, Dana W.

    2009-01-01

    Occurrence of eight selected pharmaceutically active compounds (PhACs; caffeine, carbamazepine, triclosan, gemfibrozil, diclofenac, ibuprofen, ketoprofen and naproxen) were investigated in effluents from fifteen sewage treatment plants (STPs) across South Australia. In addition, a detailed investigation into the removal of these compounds was also carried out in four STPs with different technologies (Plant A: conventional activated sludge; plant B: two oxidation ditches; plant C: three bioreactors; and plant D: ten lagoons in series). The concentrations of these compounds in the effluents from the fifteen STPs showed substantial variations among the STPs, with their median concentrations ranging from 26 ng/L for caffeine to 710 ng/L for carbamazepine. Risk assessment based on the "worst case scenario" of the monitoring data from the present study suggested potential toxic risks to aquatic organisms posed by carbamazepine, triclosan and diclofenac associated with such effluent discharge. With the exception of carbamazepine and gemfibrozil, significant concentration decreases between influent and effluent were observed in the four STPs studied in more detail. Biodegradation was found to be the main mechanism for removing concentrations from the liquid waste stream for the PhACs within the four STPs, while adsorption onto sludge appeared to be a minor process for all target PhACs except for triclosan. Some compounds (e.g. gemfibrozil) exhibited variable removal efficiencies within the four STPs. Plant D (10 lagoons in series) was least efficient in the removal of the target PhACs; significant biodegradation of these compounds only occurred from the sixth or seventh lagoon.

  18. A new parameter to simultaneously assess antioxidant activity for multiple phenolic compounds present in food products.

    Science.gov (United States)

    Yang, Hong; Xue, Xuejia; Li, Huan; Tay-Chan, Su Chin; Ong, Seng Poon; Tian, Edmund Feng

    2017-08-15

    In this work, we established a new methodology to simultaneously assess the relative reaction rates of multiple antioxidant compounds in one experimental set-up. This new methodology hypothesizes that the competition among antioxidant compounds towards limiting amount of free radical (in this article, DPPH) would reflect their relative reaction rates. In contrast with the conventional detection of DPPH decrease at 515nm on a spectrophotometer, depletion of antioxidant compounds treated by a series of DPPH concentrations was monitored instead using liquid chromatography coupled with quadrupole time-of-flight (LC-QTOF). A new parameter, namely relative antioxidant activity (RAA), has been proposed to rank these antioxidants according to their reaction rate constants. We have investigated the applicability of RAA using pre-mixed standard phenolic compounds, and also extended this application to two food products, i.e. red wine and green tea. It has been found that RAA correlates well with the reported k values. This new parameter, RAA, provides a new perspective in evaluating antioxidant compounds present in food and herbal matrices. It not only realistically reflects the antioxidant activity of compounds when co-existing with competitive constituents; and it could also quicken up the discovery process in the search for potent yet rare antioxidants from many herbs of food/medicinal origins. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Synthesis and antiproliferative activity of novel polynuclear heterocyclic compounds derived from 2,3-diaminophenazine.

    Science.gov (United States)

    Mahran, Asma M; Ragab, Sherif Sh; Hashem, Ahmed I; Ali, Mamdouh M; Nada, Afaf A

    2015-01-27

    2,3-Diaminophenazine 1 was used as a precursor for the preparation of some novel phenazine derivatives such as imidazo[4,5-b]phenazine-2-thione 2, its methylthio 3, ethyl 1-aryl-3H-[1,2,4]triazolo[2,3-a]imidazo[4,5-b]phenazines 8a-c, ethyl (2Z)-[3-aminophenazin-2-yl)amino](phenylhydrazono)ethanoate 9, pyrazino[2,3-b]phenazine derivatives 10, 12, 15-17, [1,4]diazepino[2,3-b]phenazine derivatives 13, 14, 2,3-dibenzoylaminophenazine 18, 1H-Imidazo[4,5-b]phenazine derivatives 20, 23a-c, 24, 25 and 4-[(E)-(3-amino phenazin-2-yl)diazenyl] derivatives 27-29. All compounds were tested as inhibitors of the proliferation of human lung carcinoma and colorectal cancer cell lines through inhibition of Tyrosine Kinases. Most of compounds exert good activity against the two cancer cell lines. Five compounds (1, 2, 3, 25 and 28) were found to possess the same activity as the standard drug Cisplatin. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  20. Phytochemical compounds and antioxidant activities of the almond kernel (prunus dulcis mill.) from turkey

    International Nuclear Information System (INIS)

    Keser, S.; Demir, E.; Yilmaz, O.

    2014-01-01

    Almond belong to Rosaceae family and it is a rich source of nutrients because of phytochemicals including phenolic compounds, phytosterols, flavonoids, phenolic acids, vitamins and fatty acids. In this study, we determined antioxidant activities and phenolic, flavonoid, phytosterol, lipid soluble vitamin and fatty acid contents of almond kernel extract. Antioxidant activities of almond extract was investigated by DPPH, ABTS •+ , OH radical scavenging, metal chelating activity and determination of lipid peroxidation levels (TBARS). Almond extract scavenged 89.50% of the ABTS radical, 66.77% of the hydroxyl radical, and 87.30% of the DPPH radical. This extract was shown 72.05% of the metal chelating activity. Kaempferol (223.54 μg/g), naringenin (5.01 micro g/g), vanillic acid (110.89 micro g/g), caffeic acid (65.72 micro g/g) and ferulic acid (16.49 micro g/g) were determined in the almond extract. The major fatty acids were oleic acid (76.23%) and linoleic acid (15.43%) in almond extract. d-tocopherol (3.05 mg/kg), a-tocopherol (104.40 mg/kg), and vitamin K (38.25 mg/kg) were determined in the almond extract. These results indicate that almond extract is a good natural source of fatty acids, lipid soluble vitamins, phytosterols, flavonoid, phenolic compounds. In addition, these findings are important for the nutrition sciences, because fatty acids, lipid soluble vitamins, phytosterols, flavonoid, phenolic compounds and antiradical properties, in particular, seem to have considerable effect on health. (author)

  1. Contact light-emitting diodes based on vertical ZnO nanorods

    Energy Technology Data Exchange (ETDEWEB)

    Panin, G. N. [Dongguk University, Seoul (Korea, Republic of); Russian Academy of Sciences, Chernogolovka, Moscow district (Russian Federation); Cho, H. D.; Lee, S. W.; Kang, T. W. [Dongguk University, Seoul (Korea, Republic of)

    2014-05-15

    We report vertical contact light-emitting diodes (VCLEDs), that are based on heterojunctions formed by using the point contacts of n-ZnO nanorods (NRs) to the p-type semiconductor substrate and that are fabricated using a new approach to the formation of LEDs (Appl. Phys. Lett. 98, 093110 (2011)). A p-type GaN film grown on a sapphire substrate was used to form n-ZnO NRs/pGaN VCLEDs on a large area of about 4 cm{sup 2}. The VCLEDs emitted a pure blue electroluminescence with high efficiency. Electroluminescence at 470 nm, which is visible to the naked eye, started at small current of about 50 μA and is attributed to the good optical properties of the structurally perfect heterojunctions in the point contacts. The VCLED configuration allows the creation of ZnO/p-GaN nano-LEDs of high density and high-quality with a greatly reduced concentration of nonradiative defects in the active regions. The VCLEDs showed the high brightness of light required for active matrix displays and general solid-state lighting.

  2. A comparative study of aroma-active compounds between dark and milk chocolate: relationship to sensory perception.

    Science.gov (United States)

    Liu, Jianbin; Liu, Mengya; He, Congcong; Song, Huanlu; Guo, Jia; Wang, Ye; Yang, Haiying; Su, Xiaoxia

    2015-04-01

    The most important aroma-active compounds of two types of chocolate and cocoa liquor used for their production were analysed by gas chromatography-olfactometry-mass spectrometry (GC-O-MS) and aroma extract dilution analysis (AEDA). Furthermore, the relationship between odorants and sensory perception of chocolate was measured by quantitative analysis, sensory evaluation and correlation analysis. In addition, some chemicals were added to the original dark or milk chocolate to validate their roles in the aroma property of chocolate. A total of 32 major aroma-active compounds were identified in the chocolate with the flavour dilution factors of 27-729 by AEDA, including seven aldehydes, six pyrazines, three pyrroles, four carboxylic acids, four lactones, two alcohols, two ketones, one ester, one pyrone, one furan and one sulfur-containing compound. Further quantitative analysis showed that dark chocolate had higher contents of pyrazine, pyrrole, carboxylic acids, alcohols and Strecker aldehydes, whereas the concentration of lactones, esters, long chain aldehydes and ketones were higher in the milk type. Differences in volatile composition and descriptive flavour attributes between the dark and milk chocolate were observed. The relationship between aroma-active compounds and sensory perception in the chocolate was verified. © 2014 Society of Chemical Industry.

  3. Characterization of electrically-active defects in ultraviolet light-emitting diodes with laser-based failure analysis techniques

    International Nuclear Information System (INIS)

    Miller, Mary A.; Tangyunyong, Paiboon; Cole, Edward I.

    2016-01-01

    Laser-based failure analysis techniques demonstrate the ability to quickly and non-intrusively screen deep ultraviolet light-emitting diodes (LEDs) for electrically-active defects. In particular, two laser-based techniques, light-induced voltage alteration and thermally-induced voltage alteration, generate applied voltage maps (AVMs) that provide information on electrically-active defect behavior including turn-on bias, density, and spatial location. Here, multiple commercial LEDs were examined and found to have dark defect signals in the AVM indicating a site of reduced resistance or leakage through the diode. The existence of the dark defect signals in the AVM correlates strongly with an increased forward-bias leakage current. This increased leakage is not present in devices without AVM signals. Transmission electron microscopy analysis of a dark defect signal site revealed a dislocation cluster through the pn junction. The cluster included an open core dislocation. Even though LEDs with few dark AVM defect signals did not correlate strongly with power loss, direct association between increased open core dislocation densities and reduced LED device performance has been presented elsewhere [M. W. Moseley et al., J. Appl. Phys. 117, 095301 (2015)

  4. Characterization of electrically-active defects in ultraviolet light-emitting diodes with laser-based failure analysis techniques

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Mary A.; Tangyunyong, Paiboon; Cole, Edward I. [Sandia National Laboratories, Albuquerque, New Mexico 87185-1086 (United States)

    2016-01-14

    Laser-based failure analysis techniques demonstrate the ability to quickly and non-intrusively screen deep ultraviolet light-emitting diodes (LEDs) for electrically-active defects. In particular, two laser-based techniques, light-induced voltage alteration and thermally-induced voltage alteration, generate applied voltage maps (AVMs) that provide information on electrically-active defect behavior including turn-on bias, density, and spatial location. Here, multiple commercial LEDs were examined and found to have dark defect signals in the AVM indicating a site of reduced resistance or leakage through the diode. The existence of the dark defect signals in the AVM correlates strongly with an increased forward-bias leakage current. This increased leakage is not present in devices without AVM signals. Transmission electron microscopy analysis of a dark defect signal site revealed a dislocation cluster through the pn junction. The cluster included an open core dislocation. Even though LEDs with few dark AVM defect signals did not correlate strongly with power loss, direct association between increased open core dislocation densities and reduced LED device performance has been presented elsewhere [M. W. Moseley et al., J. Appl. Phys. 117, 095301 (2015)].

  5. Emission properties of porphyrin compounds in new polymeric PS:CBP host

    Science.gov (United States)

    Jafari, Mohammad Reza; Bahrami, Bahram

    2015-06-01

    In this study, a device with fundamental structure of ITO/PEDOT:PSS (60 nm)/PS:CBP (70 nm)/Al (150 nm) was fabricated. The electroluminescence spectrum of device designated a red shift rather than PS:CBP photoluminescence spectra. It can be suggested that the electroplex emission occurs at PS:CBP interface. By following this step, red light-emitting devices using porphyrin compounds as a red dopant in a new host material PS:CBP with a configuration of ITO/PEDOT:PSS (60 nm)/PS:CBP:porphyrin compounds(70 nm)/Al (150 nm) have been fabricated and investigated. The electroluminescent spectra of the porphyrin compounds were red-shifted as compared with the PS:CBP blend. OLED devices based on doping 3,4PtTPP and TPPNO2 in PS:CBP showed purer red emission compared with ZnTPP and CoTPP doped devices. We believe that the electroluminescence performance of OLED devices based on porphyrin compounds depends on overlaps between the absorption of the porphyrin compounds and the emission of PS:CBP.

  6. Potent antifouling compounds produced by marine Streptomyces

    KAUST Repository

    Xu, Ying

    2010-02-01

    Biofouling causes huge economic loss and a recent global ban on organotin compounds as antifouling agents has increased the need for safe and effective antifouling compounds. Five structurally similar compounds were isolated from the crude extract of a marine Streptomyces strain obtained from deep-sea sediments. Antifouling activities of these five compounds and four other structurally-related compounds isolated from a North Sea Streptomyces strain against major fouling organisms were compared to probe structure-activity relationships of compounds. The functional moiety responsible for antifouling activity lies in the 2-furanone ring and that the lipophilicity of compounds substantially affects their antifouling activities. Based on these findings, a compound with a straight alkyl side-chain was synthesized and proved itself as a very effective non-toxic, anti-larval settlement agent against three major fouling organisms. The strong antifouling activity, relatively low toxicity, and simple structures of these compounds make them promising candidates for new antifouling additives. © 2009 Elsevier Ltd. All rights reserved.

  7. Antifungal activity of schinol and a new biphenyl compound isolated from Schinus terebinthifolius against the pathogenic fungus Paracoccidioides brasiliensis.

    Science.gov (United States)

    Johann, Susana; Sá, Nívea P; Lima, Luciana A R S; Cisalpino, Patricia S; Cota, Betania B; Alves, Tânia M A; Siqueira, Ezequias P; Zani, Carlos L

    2010-10-12

    The aim of this study was to isolate and identify the antifungal compounds from the extracts of Schinus terebinthifolius (Anacardiaceae) against clinical isolates of the pathogenic fungus Paracoccidioides brasiliensis. The hexane and dichlomethane fractions from leaves and stems of S. terebinthifolius were fractionated using several chromatography techniques to afford four compounds. The compounds isolated from S. terebinthifolius were identified as schinol (1), a new biphenyl compound, namely, 4'-ethyl-4-methyl-2,2',6,6'-tetrahydroxy[1,1'-biphenyl]-4,4'-dicarboxylate (2), quercetin (3), and kaempferol (4). Compounds 1 and 2 were active against different strains of P. brasiliensis, showing a minimal inhibitory concentration value against the isolate Pb B339 of 15.6 μg/ml. The isolate Pb 1578 was more sensitive to compound 1 with a MIC value of 7.5 μg/ml. Schinol presented synergistic effect only when combined with itraconazole. The compounds isolated from S. terebinthifolius were not able to inhibit cell wall synthesis or assembly using the sorbitol assay. This work reveals for the first time the occurrence of compound 2 and discloses activity of compounds 1 and 2 against several clinical isolates of P. brasiliensis. These results justify further studies to clarify the mechanisms of action of these compounds.

  8. Remanagement of Singlet and Triplet Excitons in Single-Emissive-Layer Hybrid White Organic Light-Emitting Devices Using Thermally Activated Delayed Fluorescent Blue Exciplex.

    Science.gov (United States)

    Liu, Xiao-Ke; Chen, Zhan; Qing, Jian; Zhang, Wen-Jun; Wu, Bo; Tam, Hoi Lam; Zhu, Furong; Zhang, Xiao-Hong; Lee, Chun-Sing

    2015-11-25

    A high-performance hybrid white organic light-emitting device (WOLED) is demonstrated based on an efficient novel thermally activated delayed fluorescence (TADF) blue exciplex system. This device shows a low turn-on voltage of 2.5 V and maximum forward-viewing external quantum efficiency of 25.5%, which opens a new avenue for achieving high-performance hybrid WOLEDs with simple structures. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Behaviour of gaseous alkali compounds in coal gasification; Kaasumaisten alkaliyhdisteiden kaeyttaeytyminen kivihiilien kaasutuksessa

    Energy Technology Data Exchange (ETDEWEB)

    Nykaenen, J [Imatran Voima Oy, Vantaa (Finland)

    1997-10-01

    In this project the behaviour of alkali compounds emitting from CO{sub 2}/O{sub 2}- and airblown gasification are studied. This research project is closely connected to an EU-project coordinated by the Delft University of Technology (DUT). In that project alkali emissions from a 1.6 MW pilot plant will be measured. The results from those measurements will be compared with the calculations performed in this LIEKKI 2 project. The equilibrium calculations show that the major gaseous alkali compounds emitting from combustion and gasification are chlorides and hydroxides. This applies both to air- and CO{sub 2}/O{sub 2}-blown processes. In all the cases studied the concentration of gaseous alkali compounds is determined mainly by the amount of chlorides. The key parameters, with respect to alkali behaviour, are the temperature of the process and chlorine content of the coal. By cooling the gases down to 600 deg C prior to a ceramic filter the alkali concentration can be kept about at 100 ppbv. In combustion, the addition of calcium carbonate increases the amount of gaseous alkali compounds by decreasing the amount of alkali sulphates. In the case of gasification the importance of limestone is negligible. The difference between air- and CO{sub 2}/O{sub 2}-blown processes, in terms of gaseous alkali emissions, is small. This is because CO{sub 2} concentration of the gas does not have a strong impact on alkali chlorides. Furthermore, the effect of CO{sub 2}/O{sub 2}-ratio of the recirculation process is negligible. (orig.)

  10. Efficacy of HOCl scavenging by sulfur-containing compounds: antioxidant activity of glutathione disulfide?

    NARCIS (Netherlands)

    den Hartog, G.J.M.; Haenen, G.R.M.M.; Vegt, E.; van der Vijgh, W.J.F.; Bast, A.

    2002-01-01

    Efficacy of HOCl scavenging by sulfur-containing compounds: antioxidant activity of glutathione disulfide? den Hartog GJ, Haenen GR, Vegt E, van der Vijgh WJ, Bast A. Department of Pharmacology and Toxicology, Maastricht University, The Netherlands. Hypochlorous acid (HOCl) is a bactericidal

  11. Antioxidant and antimicrobial activities of ethyl acetate extract, fractions and compounds from stem bark of Albizia adianthifolia (Mimosoideae).

    Science.gov (United States)

    Tamokou, Jean de Dieu; Simo Mpetga, Deke James; Keilah Lunga, Paul; Tene, Mathieu; Tane, Pierre; Kuiate, Jules Roger

    2012-07-18

    Albizia adianthifolia is used traditionally in Cameroon to treat several ailments, including infectious and associated diseases. This work was therefore designed to investigate the antioxidant and antimicrobial activities of ethyl acetate extract, fractions and compounds isolated from the stem bark of this plant. The plant extract was prepared by maceration in ethyl acetate. Its fractionation was done by column chromatography and the structures of isolated compounds were elucidated using spectroscopic data in conjunction with literature data. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) and trolox equivalent antioxidant capacity (TEAC) assays were used to detect the antioxidant activity. Broth micro-dilution method was used for antimicrobial test. Total phenol content was determined spectrophotometrically in the extracts by using Folin-Ciocalteu method. The fractionation of the extract afforded two known compounds: lupeol (1) and aurantiamide acetate (2) together with two mixtures of fatty acids: oleic acid and n-hexadecanoic acid (B₁); n-hexadecanoic acid, octadecanoic acid and docosanoic acid (B₂). Aurantiamide acetate was the most active compound. The total phenol concentration expressed as gallic acid equivalents (GAE) was found to vary from 1.50 to 13.49 μg/ml in the extracts. The antioxidant activities were well correlated with the total phenol content (R² = 0.946 for the TEAC method and R² = 0.980 for the DPPH free-radical scavenging assay). Our results clearly reveal that the ethyl acetate extract from the stem bark of A. adianthifolia possesses antioxidant and antimicrobial principles. The antioxidant activity of this extract as well as that of compound 2 are being reported herein for the first time. These results provide promising baseline information for the potential use of this plant as well as compound 2 in the treatment of oxidative damage and infections associated with the studied microorganisms.

  12. Synthesis and characterization of pure and Li⁺ activated Alq₃ complexes for green and blue organic light emitting diodes and display devices.

    Science.gov (United States)

    Bhagat, S A; Borghate, S V; Kalyani, N Thejo; Dhoble, S J

    2014-08-01

    Pure and Li(+)-doped Alq3 complexes were synthesized by simple precipitation method at room temperature, maintaining the stoichiometric ratio. These complexes were characterized by X-ray diffraction, ultraviolet-visible absorption and Fourier transform infrared and photoluminescence (PL) spectra. X-ray diffraction analysis reveals the crystalline nature of the synthesized complexes, while Fourier transform infrared spectroscopy confirm the molecular structure, the completion of quinoline ring formation and presence of quinoline structure in the metal complex. Ultraviolet-visible and PL spectra revealed that Li(+) activated Alq3 complexes exhibit the highest intensity in comparison to pure Alq3 phosphor. Thus, Li(+) enhances PL emission intensity when doped into Alq3 phosphor. The excitation spectra lie in the range of 383-456 nm. All the synthesized complexes other than Liq give green emission, while Liq gives blue emission with enhanced intensity. Thus, he synthesized phosphors are the best suitable candidates for green- and blue-emitting organic light emitting diode, PL liquid-crystal display and solid-state lighting applications. Copyright © 2013 John Wiley & Sons, Ltd.

  13. All-inorganic white light emitting devices based on ZnO nanocrystals

    Energy Technology Data Exchange (ETDEWEB)

    Nannen, Ekaterina

    2012-09-21

    Semiconductor nanaocrystals (NCs) are very promising candidates for lightweight large-area rollable displays and light emitting devices (LEDs). They are expected to combine the efficiency, robustness and color tunability of conventional semiconductor LEDs with the flexible fabrication techniques known from OLED technology, since the NCs are compatible with solution processing and therefore can be deposited on virtually any substrates including glass and plastic. Today, NC-LEDs consist of chemically synthesized QDs embedded in organic charge injection and transport layers. The organic layers limit the robustness of the NC-LEDs and result in significant constrictions within the device fabrication procedure, such as organic evaporation steps, inert (i.e. humidity and oxygen free) atmosphere and obligatory encapsulation. These limitations during the production process as well as complex chemical synthesis route of the implemented NCs and organic components lead to high fabrication costs and low turnover. So far, only prototype devices have been introduced by several research groups and industrial companies. Still, the main concern retarding NC-LEDs from market launch is the high content of toxic heavy metals like Cd in the active nanocrystalline light emitting material. Within this work, possible environmentally safe and ambient-air-compatible alternatives to conventional QDs and organics were explored, with the main focus on design and fabrication of completely inorganic white NC-LEDs with commercial ZnO nanoparticles as an active light emitting material. While the electrical transport properties through the NC-network of the commercially available VP AdNano {sup registered} ZnO2O particles were already to some extent explored, their optical properties and therefore suitability as an active light emitter in NC-LEDs were not studied so far. (orig.)

  14. Luminescent properties of UV excitable blue emitting phosphors MSr4(BO3)3:Ce3+ (M = Li and Na)

    International Nuclear Information System (INIS)

    Guo Chongfeng; Ding Xu; Seo, Hyo Jin; Ren Zhaoyu; Bai Jintao

    2011-01-01

    Research highlights: → Novel blue emitting phosphors borate MSr 4 (BO 3 ) 3 (M = Li or Na) were prepared first. → Luminescent properties of phosphors borate MSr 4 (BO 3 ) 3 (M = Li or Na) were investigated extensively as candidates of blue emitting phosphor used for UV excited LED. → The optimal concentrations of dopant Ce 3+ ions in compound MSr 4 (BO 3 ) 3 (M = Li or Na) were determined as 0.05 for Li and x = 0.09 for Na excited by UV light respectively. - Abstract: A series of Ce 3+ doped novel borate phosphors MSr 4 (BO 3 ) 3 (M = Li or Na) were successfully synthesized by traditional solid-state reaction. The crystal structures and the phase purities of samples were characterized by powder X-ray diffraction. The optimal concentrations of dopant Ce 3+ ions in compound MSr 4 (BO 3 ) 3 (M = Li or Na) were determined through the measurements of photoluminescence spectra of phosphors. Ce 3+ doped phosphors MSr 4 (BO 3 ) 3 (M = Li or Na) show strong broad band absorption in UV spectral region and bright blue emission under the excitation of 345 nm light. In addition, the temperature dependences of emission spectra of M 1+x Sr 4-2x Ce x (BO 3 ) 3 (M = Li or Na) phosphors with optimal composition x = 0.05 for Li and x = 0.09 for Na excited under 355 nm pulse laser were also investigated. The experimental results indicate that the M 1+x Sr 4-2x Ce x (BO 3 ) 3 (M = Li or Na) phosphors are promising blue emitting phosphors pumped by UV light.

  15. Light Converting Inorganic Phosphors for White Light-Emitting Diodes

    OpenAIRE

    Chen, Lei; Lin, Chun-Che; Yeh, Chiao-Wen; Liu, Ru-Shi

    2010-01-01

    White light-emitting diodes (WLEDs) have matched the emission efficiency of florescent lights and will rapidly spread as light source for homes and offices in the next 5 to 10 years. WLEDs provide a light element having a semiconductor light emitting layer (blue or near-ultraviolet (nUV) LEDs) and photoluminescence phosphors. These solid-state LED lamps, rather than organic light emitting diode (OLED) or polymer light-emitting diode (PLED), have a number of advantages over conventional incand...

  16. Phenolic compounds from the flowers of Nepalese medicinal plant Aconogonon molle and their DPPH free radical-scavenging activities.

    Science.gov (United States)

    Joshi, Khem Raj; Devkota, Hari Prasad; Watanabe, Takashi; Yahara, Shoji

    2014-01-01

    Eleven phenolic compounds, quercetin (1), quercetin 3-O-β-d-galactopyranoside (2), quercetin 3-O-(6″-O-galloyl)-β-d-galactopyranoside (3), quercetin 3-O-(6″-O-caffeoyl)-β-d-galactopyranoside (4), quercetin 3-O-β-d-glucopyranoside (5), rutin (6) quercetin 3-O-α-l-arabinopyranoside (7), quercetin 3-O-α-l-arabinofuranoside (8), protocatechulic acid (9), gallic acid (10) and chlorogenic acid (11), were isolated from the flowers of Aconogonon molle, a Nepalese medicinal plant. Structures of these compounds were elucidated on the basis of spectroscopic methods. All these compounds were isolated for the first time from flowers, and five compounds (4, 5, 8, 9 and 11) were isolated for the first time from A. molle. All of these isolated compounds were evaluated for their in vitro antioxidant activity by using the 1,1-diphenyl-2-picrylhydrazyl radical-scavenging method. Quercetin (1), quercetin glycosides (2-8) and gallic acid (10) exhibited potent antioxidant activity.

  17. Exploratory Characterization of Phenolic Compounds with Demonstrated Anti-Diabetic Activity in Guava Leaves at Different Oxidation States

    OpenAIRE

    D?az-de-Cerio, Elixabet; Verardo, Vito; G?mez-Caravaca, Ana Mar?a; Fern?ndez-Guti?rrez, Alberto; Segura-Carretero, Antonio

    2016-01-01

    Psidium guajava L. is widely used like food and in folk medicine all around the world. Many studies have demonstrated that guava leaves have anti-hyperglycemic and anti-hyperlipidemic activities, among others, and that these activities belong mainly to phenolic compounds, although it is known that phenolic composition in guava tree varies throughout seasonal changes. Andalusia is one of the regions in Europe where guava is grown, thus, the aim of this work was to study the phenolic compounds ...

  18. Inducers of Senescence, Toxic Compounds, and Senolytics: The Multiple Faces of Nrf2-Activating Phytochemicals in Cancer Adjuvant Therapy

    Directory of Open Access Journals (Sweden)

    Marco Malavolta

    2018-01-01

    Full Text Available The reactivation of senescence in cancer and the subsequent clearance of senescent cells are suggested as therapeutic intervention in the eradication of cancer. Several natural compounds that activate Nrf2 (nuclear factor erythroid-derived 2-related factor 2 pathway, which is involved in complex cytoprotective responses, have been paradoxically shown to induce cell death or senescence in cancer. Promoting the cytoprotective Nrf2 pathway may be desirable for chemoprevention, but it might be detrimental in later stages and advanced cancers. However, senolytic activity shown by some Nrf2-activating compounds could be used to target senescent cancer cells (particularly in aged immune-depressed organisms that escape immunosurveillance. We herein describe in vitro and in vivo effects of fifteen Nrf2-interacting natural compounds (tocotrienols, curcumin, epigallocatechin gallate, quercetin, genistein, resveratrol, silybin, phenethyl isothiocyanate, sulforaphane, triptolide, allicin, berberine, piperlongumine, fisetin, and phloretin on cellular senescence and discuss their use in adjuvant cancer therapy. In light of available literature, it can be concluded that the meaning and the potential of adjuvant therapy with natural compounds in humans remain unclear, also taking into account the existence of few clinical trials mostly characterized by uncertain results. Further studies are needed to investigate the therapeutic potential of those compounds that display senolytic activity.

  19. Marine Invertebrate Xenobiotic-Activated Nuclear Receptors: Their Application as Sensor Elements in High-Throughput Bioassays for Marine Bioactive Compounds

    Directory of Open Access Journals (Sweden)

    Ingrid Richter

    2014-11-01

    Full Text Available Developing high-throughput assays to screen marine extracts for bioactive compounds presents both conceptual and technical challenges. One major challenge is to develop assays that have well-grounded ecological and evolutionary rationales. In this review we propose that a specific group of ligand-activated transcription factors are particularly well-suited to act as sensors in such bioassays. More specifically, xenobiotic-activated nuclear receptors (XANRs regulate transcription of genes involved in xenobiotic detoxification. XANR ligand-binding domains (LBDs may adaptively evolve to bind those bioactive, and potentially toxic, compounds to which organisms are normally exposed to through their specific diets. A brief overview of the function and taxonomic distribution of both vertebrate and invertebrate XANRs is first provided. Proof-of-concept experiments are then described which confirm that a filter-feeding marine invertebrate XANR LBD is activated by marine bioactive compounds. We speculate that increasing access to marine invertebrate genome sequence data, in combination with the expression of functional recombinant marine invertebrate XANR LBDs, will facilitate the generation of high-throughput bioassays/biosensors of widely differing specificities, but all based on activation of XANR LBDs. Such assays may find application in screening marine extracts for bioactive compounds that could act as drug lead compounds.

  20. Synthesis and Antimicrobial Activity of New Schiff Base Compounds Containing 2-Hydroxy-4-pentadecylbenzaldehyde Moiety

    Directory of Open Access Journals (Sweden)

    Gadada Naganagowda

    2014-01-01

    Full Text Available Various novel Schiff base compounds have been synthesized by reaction of 2-hydroxy-4-pentadecylbenzaldehyde with substituted benzothiophene-2-carboxylic acid hydrazide and different substituted aromatic or heterocyclic amines in the presence of acetic acid in ethanol. The structures of all these compounds were confirmed by elemental analysis, IR, 1H-NMR, 13C-NMR, and mass spectral data and have been screened for antibacterial and antifungal activity.