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Sample records for k2co3 chemical activation

  1. Preparation and surface characterization of activated carbons from Euphorbia rigida by chemical activation with ZnCl2, K2CO3, NaOH and H3PO4

    International Nuclear Information System (INIS)

    Kılıç, Murat; Apaydın-Varol, Esin; Pütün, Ayşe Eren

    2012-01-01

    Highlights: ► An arid land plant evaluated as low cost activated carbon precursor. ► Four types of different chemical activation agents are used. ► Higher surface area (2600 m 2 /g) obtained by chemical activation. ► Obtained activated carbon can be effectively used as an adsorbent for the removal of toxic pollutants from aqueous solutions. - Abstract: Preparation of activated carbons from Euphorbia rigida by chemical activation with different impregnation agents and ratios was studied. ZnCl 2 , K 2 CO 3 , NaOH and H 3 PO 4 were used as chemical activation agents and four impregnation ratios (25–50–75–100%) by mass were applied on biomass. Activation is applied to impregnated biomass samples at 700 °C under sweeping gas in a fixed bed reactor. For determination of chemical and physical properties of the obtained activated carbons; elemental analysis was applied to determine the elemental composition (C, H, N, O) and FT-IR spectra was used to analyze the functional groups. BET equation was used to calculate the surface areas of activated carbons. For understanding the changes in the surface structure, activated carbons were conducted to Scanning Electron Microscopy (SEM). Maximum BET surface area (2613 m 2 /g) was reached with 75% K 2 CO 3 impregnated biomass sample. Experimental results showed that impregnation types and ratios have a significant effect on the pore structure of activated carbon and E. rigida seems to be an alternative precursor for commercial activated carbon production.

  2. Preparation and Characterization of K2CO3-Activated Kraft Lignin Carbon

    Directory of Open Access Journals (Sweden)

    Xian-fa Li

    2016-01-01

    Full Text Available A series of activated carbons (ACs were prepared by K2CO3 activation from kraft lignin (KL that was recovered from papermaking black liquor. The effects of process parameters such as the activation temperature (AT, activated period, K2CO3 to KL mass ratio, and N2 flow rate on the characteristics of the final product were determined. The ACs were characterized using nitrogen adsorption, morphology, and fractal dimension analyses. The results showed that the AT was the main factor influencing the yield, surface area, and pore structure. The yield of ACs obviously decreased from 50.6% to 20.5% with increasing AT from 600 °C to 1000 °C, and decreased with increasing K2CO3/KL mass ratio. Activation time and N2 flow rate had slight effect on the yield of ACs. The surface area and total pore volume increased as the AT rose to 900 °C and then decreased with further increases in temperature. The maximum surface area and total pore volume were 1816.3 m2/g and 1.26 cm3/g, respectively, at a K2CO3 to KL mass ratio of 3:1, AT of 900 °C, activation time of 2 h, and N2 flow rate of 70 cm3/min. The pore structure of the ACs could be tailored by controlling the AT. As the AT was increased from 700 to 1000 °C, the mesoporosity increased from 11.6% to 95.9%. SEM images indicated that the morphology of ACs was modified by the AT. The K2CO3 was partially recycled.

  3. Chars from gasification of coal and pine activated with K2CO3: acetaminophen and caffeine adsorption from aqueous solutions.

    Science.gov (United States)

    Galhetas, Margarida; Mestre, Ana S; Pinto, Moisés L; Gulyurtlu, Ibrahim; Lopes, Helena; Carvalho, Ana P

    2014-11-01

    The high carbon contents and low toxicity levels of chars from coal and pine gasification provide an incentive to consider their use as precursors of porous carbons obtained by chemical activation with K2CO3. Given the chars characteristics, previous demineralization and thermal treatments were made, but no improvement on the solids properties was observed. The highest porosity development was obtained with the biomass derived char (Pi). This char sample produced porous materials with preparation yields near 50% along with high porosity development (ABET≈1500m(2)g(-1)). For calcinations at 800°C, the control of the experimental conditions allowed the preparation of samples with a micropore system formed almost exclusively by larger micropores. A mesopore network was developed only for samples calcined at 900°C. Kinetic and equilibrium acetaminophen and caffeine adsorption data, showed that the processes obey to a pseudo-second order kinetic equation and to the Langmuir model, respectively. The results of sample Pi/1:3/800/2 outperformed those of the commercial carbons. Acetaminophen adsorption process was ruled by the micropore size distribution of the carbons. The caffeine monolayer capacities suggest a very efficient packing of this molecule in samples presenting monomodal micropore size distribution. The surface chemistry seems to be the determinant factor that controls the affinity of caffeine towards the carbons. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Mechanochemical synthesis of CaO•ZnO.K2CO3 catalyst: Characterization and activity for methanolysis of sunflower oil

    Directory of Open Access Journals (Sweden)

    Kesić Željka

    2015-01-01

    Full Text Available The goal of this study was to prepare CaO.ZnO catalyst which contain small amount of K2CO3 and analyze its activity for biodiesel synthesis. Catalyst was prepared using the following procedure: CaO and ZnO (molar ratio of 1:2, water and K2CO3 (in various amounts were mechanochemically treated and after milling heated at 700 oC in air atmosphere for obtaining mixed CaO•ZnO/xK2CO3 oxides (x = 0, 1, 2 and 4; mole of K2CO3 per 10 mole of CaO. All the samples were characterized by X-ray diffraction (XRD, inductively coupled plasma (ICP, X-ray photoelectron spectroscopy (XPS, thermogravimetric analysis (TGA, infrared spectroscopy (FTIR, scanning electron microscopy/energy-dispersive spectroscopy (SEM/EDS, particle size laser diffraction (PSLD distribution, solubility measurement of Ca, Zn and K ions in methanol as well as by determination of their alkalinity (Hammett indicator method. Prepared CaO•ZnO/xK2CO3 composite powders were tested as catalysts for methanolysis of sunflower oil at 70ºC using molar ratio of sunflower oil to methanol of 1:10 and with 2 mas% of catalyst based on oil weight. The presence of K2CO3 in prepared samples was found to increase the activity of catalyst, and that such effect is caused by homogeneous-heterogeneous catalysis of biodiesel synthesis. [Projekat Ministarstva nauke Republike Srbije, br. 45001

  5. Influence of K3Fe(CN)6 on the electrochemical performance of carbon derived from waste tyres by K 2CO3 activation

    CSIR Research Space (South Africa)

    Bello, A

    2018-04-01

    Full Text Available ) in the presence of potassium carbonate (K 2CO3) salt as the activating agent. The activated carbon (AC) materials exhibited predominantly mesoporous framework with specific surface area between 147 and 385 m2 g-1. Fabricated electrodes from these AC materials...

  6. Porous carbon from local coconut shell char by CO2 and H2O activation in the presence of K2CO3

    Science.gov (United States)

    Vi, Nguyen Ngoc Thuy; Truyen, Dang Hai; Trung, Bien Cong; An, Ngo Thanh; Van Dung, Nguyen; Long, Nguyen Quang

    2017-09-01

    Vietnamese coconut shell char was activated by steam and carbon dioxide at low temperatures with the presence of K2CO3 as a catalyst. The effects of process parameters on adsorption capability of the product including different ratio of impregnation of activation agents, activation temperature, activation time were investigated in this study. Iodine number, methylene blue adsorption capacity, specific surface area and pore size distribution were measured to assess the properties of the activated carbon. Accordingly, the porous carbon was applied for toluene removal by adsorption technology. Significant increases in specific surface area and the toluene adsorption capacity were observed when the coconut shell char was activated in CO2 flow at 720 °C for 150 minutes and the K2CO3/char weight ratio of 0.5.

  7. Chemical and Electrochemical Asymmetric Dihydroxylation of Olefins in I(2)-K(2)CO(3)-K(2)OsO(2)(OH)(4) and I(2)-K(3)PO(4)/K(2)HPO(4)-K(2)OsO(2)(OH)(4) Systems with Sharpless' Ligand.

    Science.gov (United States)

    Torii, Sigeru; Liu, Ping; Bhuvaneswari, Narayanaswamy; Amatore, Christian; Jutand, Anny

    1996-05-03

    Iodine-assisted chemical and electrochemical asymmetric dihydroxylation of various olefins in I(2)-K(2)CO(3)-K(2)OsO(2)(OH)(4) and I(2)-K(3)PO(4)/K(2)HPO(4)-K(2)OsO(2)(OH)(4) systems with Sharpless' ligand provided the optically active glycols in excellent isolated yields and high enantiomeric excesses. Iodine (I(2)) was used stoichiometrically for the chemical dihydroxylation, and good results were obtained with nonconjugated olefins in contrast to the case of potassium ferricyanide as a co-oxidant. The potentiality of I(2) as a co-oxidant under stoichiometric conditions has been proven to be effective as an oxidizing mediator in electrolysis systems. Iodine-assisted asymmetric electro-dihydroxylation of olefins in either a t-BuOH/H(2)O(1/1)-K(2)CO(3)/(DHQD)(2)PHAL-(Pt) or t-BuOH/H(2)O(1/1)-K(3)PO(4)/K(2)HPO(4)/(DHQD)(2)PHAL-(Pt) system in the presence of potassium osmate in an undivided cell was investigated in detail. Irrespective of the substitution pattern, all the olefins afforded the diols in high yields and excellent enantiomeric excesses. A plausible mechanism is discussed on the basis of cyclic voltammograms as well as experimental observations.

  8. Simulation and modeling CO2 absorption in biogas with DEA promoted K2CO3 solution in packed column

    Science.gov (United States)

    Nurkhamidah, Siti; Altway, Ali; Airlangga, Bramantyo; Emilia, Dwi Putri

    2017-05-01

    Absorption of carbon dioxide (CO2) using potassium carbonate (K2CO3) is one of biogas purification method. However, K2CO3 have slow mass transfer in liquid phase. So it is necessary to eliminate the disadvantage of CO2 absorption using K2CO3 by adding promotor (activator). Diethanol amine (DEA) is one of promotor which can increase its reaction rate. Simulation and modeling research of the CO2 absorption from biogas with DEA promoted K2CO3 solution has not been conducted. Thus, the main goal of this research is create model and simulation for the CO2 absorption from biogas with DEA promoted K2CO3 solution, then observe the influence of promoter concentration. DEA concentration varies between 1-5 %wt. From the simulation, we concluded that the CO2 removal rise with the increasing of promoter concentration. The highest CO2 removal is 54.5318 % at 5 % wt DEA concentration.

  9. Interfacially controlled phenomena in the system K2CO3-KAlO2

    International Nuclear Information System (INIS)

    Cook, L.P.

    1981-01-01

    Potassium carbonate has become of special interest to a number of ceramists because of its use as ionizing seed material which is added to combustion gases to produce a conductive plasma in magnetohydrodynamic electrical power generators. In this high temperature environment, chemical interaction occurs not only with ceramic components of the system such as electrodes and insulators, but also with the mineral ash of the coal used to fuel the generator. As a result, potassium aluminate is an important component of the slags accummulating in such generators. The system K 2 CO 3 -KAlO 2 is under investigation as part of a more general study of potassium carbonate - slag interaction. This note is a summary of some preliminary observations on the phase equilibria of K 2 CO 3 -KAlO 2 with focus on the unusual melting behavior of Kat''CO 3 /KAlO 2 mixtures which appears to have its origin in interfacial interaction

  10. Biodiesel synthesis using K2CO3/Al–O–Si aerogel catalysts

    Directory of Open Access Journals (Sweden)

    IVANA LUKIĆ

    2010-06-01

    Full Text Available In this study, catalysts for fatty acid methyl esters (FAME or bio-diesel synthesis with K2CO3 as the active component on an alumina/silica support were synthesized using the sol–gel method, which was followed by drying the “dense” wet gels with supercritical carbon dioxide to obtain the aerogels. The prepared catalysts were characterized by XRD analysis, FTIR spectroscopy and N2 physisorption at 77 K, and tested in the methanolysis of sunflower oil. The effects of reaction variables, such as reaction time, temperature and methanol to oil molar ratio, on the yield of FAME were investigated. The aerogel catalysts with K2CO3 as the active component on an alumina/silica support exhibited good activity in the methanolysis of sunflower oil. The leaching of potassium when the catalyst was in contact with pure methanol under the working conditions of methanolysis was also tested in this study, indicating that it occurred only at higher temperatures, while at lower ones, it was negligible.

  11. Effect of CaCO_3 addition on ash sintering behaviour during K_2CO_3 catalysed steam gasification of a Chinese lignite

    International Nuclear Information System (INIS)

    Zhang, Jiguang; Li, Jianbo; Mao, Yandong; Bi, Jicheng; Zhu, Mingming; Zhang, Zhezi; Zhang, Li; Zhang, Dongke

    2017-01-01

    Highlights: • K_2CO_3 decreased ash sintering temperature and enhanced ash melting in gasification. • CaCO_3 addition enhanced ash melting and lowered ash sintering temperatures. • CaCO_3 reacted with SiO_2 to form fluxing phases and amorphous materials. • CaCO_3 addition inhibited the potassium aluminium silicate formation. • CaCO_3 addition preserved the catalytic activity of potassium. - Abstract: The ash sintering behaviour of a Chinese lignite (LLI) with different amounts of CaCO_3 addition during K_2CO_3-catalysed gasification was investigated. 0–10 wt% K_2CO_3 was doped into the lignite for catalytic gasification, and CaCO_3 was added into the K_2CO_3-doped samples, varying in the range of 0–20 wt% relative to the lignite, for understanding its impact on ash sintering and catalytic gasification activity. Ash samples were prepared by completely gasifying the lignite samples with steam in a fixed-bed catalytic gasification system operating at 1073 K and atmospheric pressure. Sintering temperature, mineralogy and morphology of the ash samples thus obtained were determined using a pressure-drop sintering device, XRD and SEM-EDS, respectively. The results showed that the ash sintering temperature decreased as the K_2CO_3 addition increased, indicating that K_2CO_3 as the catalyst for gasification would promote ash sintering. SEM imaging analysis showed that all the ash samples from LLI with K_2CO_3 addition were composed of agglomerated particles with smooth surfaces, indicating the ashes had incurred partial melting. The degree of melting became more apparent as the K_2CO_3 addition ratio increased. These molten phases were identified as K-bearing arcanite and kaliophilite, which contributed to the formation of liquid phases at lower temperatures, resulting in lowered ash sintering temperatures. It was also revealed that the addition of CaCO_3 decreased the sintering temperatures of ash samples, indicating that the ash sintering was further

  12. Electrochemical deposition of carbon films on titanium in molten LiCl–KCl–K2CO3

    International Nuclear Information System (INIS)

    Song, Qiushi; Xu, Qian; Wang, Yang; Shang, Xujing; Li, Zaiyuan

    2012-01-01

    Electrodeposition of carbon films on the oxide-scale-coated titanium has been performed in a LiCl–KCl–K 2 CO 3 melt, which are characterized by scanning electron microscopy, Raman spectroscopy and X-ray diffraction analysis. The electrochemical process of carbon deposition is investigated by cyclic voltammetry on the graphite, titanium and oxide-scale-coated titanium electrodes. The particle-size-gradient carbon films over the oxide-scale-coated titanium can be achieved by electrodeposition under the controlled potentials for avoiding codeposition of lithium carbide. The deposited carbon films are comprised of micron-sized ‘quasi-spherical’ carbon particles with graphitized and amorphous phases. The cyclic voltammetry behavior on the graphite, titanium and oxide-scale-coated titanium electrodes shows that CO 3 2− ions are reduced most favorably on the graphite for the three electrodes. Lithium ions can discharge under the less negative potential on the electrode containing carbon compared with titanium electrode because of the formation of lithium carbide from the reaction between lithium and carbon. - Highlights: ► Carbon films are prepared on oxide-scale-coated titanium in a LiCl–KCl–K 2 CO 3 melt. ► The films comprise micron-size ‘quasi-spherical’ carbon particles. ► The films present particle-size-gradient. ► The particles contain graphitized and amorphous phases. ► The prepared carbon films are more electrochemically active than graphite.

  13. Potassium Capture by Kaolin, Part 2: K2CO3, KCI, and K2SO4

    DEFF Research Database (Denmark)

    Wang, Guoliang; Jensen, Peter Arendt; Wu, Hao

    2018-01-01

    residence time on the reaction was investigated. The results showed that the K-capture level (C-K) (g potassium reacted by per g kaolin available) of K2CO3 and KCI by kaolin generally followed the equilibrium predictions at temperatures above 1100 degrees C, when using a kaolin particle size of D50 = 5.......47 mu m and a residence time of 1.2 s. This revealed that a nearly full conversion was obtained without kinetic or transport limitations at the conditions applied. At 800 and 900 degrees C, the measured conversions were lower than the equilibrium predictions, indicating that the reactions were either...

  14. Effect of Promoter Concentration on CO2 Separation Using K2CO3 With Reactive Absorption Method in Reactor Packed Column

    Directory of Open Access Journals (Sweden)

    Monde Junety

    2018-01-01

    Full Text Available The presence of carbon dioxide (CO2 in the gas is not expected because CO2 can reduce heating value and CO2 is the major emission contributor into the atmosphere. Various separation technologies can be used to reduce CO2 content and improve quality of gas. Chemical or reactive absorption is most widely used because it provides higher removal rate. This paper will study the effect of the addition di ethanolamine (DEA concentration into aqueous 30wt.% potassium carbonate(K2CO3 with reactive absorption method in a reactor packed column at temperature from 40°C to 80°C, DEA concentration range of (1% - 3% and absorbent flow rate (0.5, 0.75 and 1 L. min1. Contacting the gas and absorbent are countercurrent flow in packed column with 1.5 m high and 50 mm in diameter. The absorption column was randomly packed with a packing material raschig rings 5 mm in diameter. The CO2 loading in the liquid samples was determined by titration. It is found that the best result of CO2 loading is 0.065594 mole/mole K2CO3 and CO2 removal 28%. The result show that the loading capacity (mole CO2/mole K2CO3 and CO2 removal increased with the increase of DEA concentration.

  15. Biodiesel production from rice bran oil by transesterification using heterogeneous catalyst natural zeolite modified with K2CO3

    Science.gov (United States)

    Taslim; Iriany; Bani, O.; Parinduri, S. Z. D. M.; Ningsih, P. R. W.

    2018-02-01

    In the present study, an effort had been made to use natural zeolite from Tapanuli Utara, North Sumatera as a potential catalyst for biodiesel production. Biodiesel production is usuallythrough transesterification, and a catalyst is employed to improve reaction rate and yield. In this research rice bran oil (RBO) was used as feedstock. The objective of this work was to discover the effectiveness of natural zeolite modified by K2CO3 as catalysts in biodiesel production from RBO. K2CO3/natural zeolite catalyst modification was by impregnation method at various K2CO3 concentrations followed by drying and calcination. Transesterification was conducted at 65°C and 500 rpm. Effect of process variables such as the amount of catalyst, reaction time, and the molar ratio of methanol to RBO was investigated.The maximum yield of 98.18% biodiesel was obtained by using 10:1 molar ratio of methanol to RBO at a reaction time of 3 hours in the presence of 4 w% catalyst. The obtained biodiesel was then characterized by its density, viscosity and ester content. The biodiesel properties met the Indonesia standard (SNI).The results showed that natural zeolite modified by K2CO3 was suitable as a catalyst in the synthesis of biodiesel through transesterification from RBO.

  16. Critical current density improvements in MgB2 superconducting bulk samples by K2CO3 additions  

    DEFF Research Database (Denmark)

    Grivel, J.-C.

    2018-01-01

    MgB2 bulk samples with potassium carbonate doping were made by means of reaction of elemental Mg and B powders mixed with various amounts of K2CO3. The Tc of the superconducting phase as well as its a-axis parameter were decreased as a result of carbon doping. Potassium escaped the samples during...... reaction. The critical current density of MgB2 was improved both in self field and under applied magnetic field for T ≤ 30 K, with optimum results for 1 mol% K2CO3 addition. The normalized flux pinning force (f(b)) shows that the flux pinning mechanism at low field is similar for all samples, following...

  17. Phase formation in K2O(K2CO3)-CdO-MoO3 system

    International Nuclear Information System (INIS)

    Tsirenova, G.D.; Tsybikova, B.A.; Bazarova, Zh.G.; Solodovnikov, S.F.; Zolotova, E.S.

    2000-01-01

    Phase formation in K 2 O(K 2 CO 3 )-CdO-MoO 3 system are studied by the methods of x-ray diffraction, thermal and crystal optical analyses. Three potassium-cadmium molybdates are detected: K 4 Cd(MoO 4 ) 3 with a new structure, alluodite-like K 4-2x Cd 1+x (MoO 4 ) 3 (0.26≤x≤0.38 at 470 Deg C) and K 4 CdMo 4 O 15 of K 4 MnMo 4 O 15 type. First of them decomposes in solid phase at 580 Deg C, and others melt incongruently at 720 and 515 Deg C correspondingly. It is established that K 4-2x Cd 1+x (MoO 4 ) 3 compound undergoes phase transition of the second type in the temperature interval of 500-550 Deg C. Phase diagram of quasibinary cross section K 2 MoO 4 -CdMoO 4 is plotted [ru

  18. Synthesis and optical properties of SiO2–Al2O3–MgO–K2CO3–CaO ...

    Indian Academy of Sciences (India)

    Synthesis and optical properties of SiO 2 –Al 2 O 3 –MgO–K 2 CO 3 –CaO–MgF 2 –La 2 O 3 glasses. C R GAUTA. Volume 39 Issue 3 June 2016 pp 677-682 ... Author Affiliations. C R GAUTA1. Advanced Glass and Glass Ceramic Research Laboratory, Department of Physics, University of Lucknow, Lucknow 226007, India ...

  19. Phase and morphology evolution of (Na1-xKxNbO3 powders related to calcinations and K2CO3 content

    Directory of Open Access Journals (Sweden)

    Steven J. Milne

    2007-03-01

    Full Text Available Sodium-potassium niobate ((Na1-xKxNbO3 powders with x = 0.2, 0.4, 0.6 and 0.8 were prepared following the conventional mixed oxide method and characterized by TG-DTA, XRD and SEM techniques.The effects of calcination temperature, dwell time and K2CO3 content on phase formation behavior and morphology of the powders were investigated. The calcination temperature and dwell time were found tohave a pronounced effect on the phase formation of the calcined sodium-potassium niobate powders. It was found that the crystallized phase depended on calcination conditions. The high calcination temperature andlong dwell time clearly favored particle growth and the formation of large and hard agglomerates. All the (Na1-xKxNbO3 powders showed a similar orthorhombic phase structure. The K2CO3 content significantlyaffected the calcination temperature and particle size and shape. Large particle size, cubic shape and a lower calcined condition were observed in (Na1-xKxNbO3 powder with low K2CO3 content (x = 0.2.

  20. A kinetic study on the catalysis of KCl, K2SO4, and K2CO3 during oxy-biomass combustion.

    Science.gov (United States)

    Deng, Shuanghui; Wang, Xuebin; Zhang, Jiaye; Liu, Zihan; Mikulčić, Hrvoje; Vujanović, Milan; Tan, Houzhang; Duić, Neven

    2018-07-15

    Biomass combustion under the oxy-fuel conditions (Oxy-biomass combustion) is one of the approaches achieving negative CO 2 emissions. KCl, K 2 CO 3 and K 2 SO 4 , as the major potassium species in biomass ash, can catalytically affect biomass combustion. In this paper, the catalysis of the representative potassium salts on oxy-biomass combustion was studied using a thermogravimetric analyzer (TGA). Effects of potassium salt types (KCl, K 2 CO 3 and K 2 SO 4 ), loading concentrations (0, 1, 3, 5, 8 wt%), replacing N 2 by CO 2 , and O 2 concentrations (5, 20, 30 vol%) on the catalysis degree were discussed. The comparison between TG-DTG curves of biomass combustion before and after water washing in both the 20%O 2 /80%N 2 and 20%O 2 /80%CO 2 atmospheres indicates that the water-soluble minerals in biomass play a role in promoting the devolatilization and accelerating the char-oxidation; and the replacement of N 2 by CO 2 inhibits the devolatilization and char-oxidation processes during oxy-biomass combustion. In the devolatilization stage, the catalysis degree of potassium monotonously increases with the increase of potassium salt loaded concentration. The catalysis degree order of the studied potassium salts is K 2 CO 3  > KCl > K 2 SO 4 . In the char-oxidation stage, with the increase of loading concentration the three kinds of potassium salts present inconsistent change tendencies of the catalysis degree. In the studied loading concentrations from 0 to 8 wt%, there is an optimal loading concentration for KCl and K 2 CO 3 , at 3 and 5 wt%, respectively; while for K 2 SO 4 , the catalysis degree on char-oxidation monotonically increases with the loading potassium concentration. For most studied conditions, regardless of the potassium salt types or the loading concentrations or the combustion stages, the catalysis degree in the O 2 /CO 2 atmosphere is stronger than that in the O 2 /N 2 atmosphere. The catalysis degree is also affected by the O 2

  1. The Density and Compressibility of BaCO3-SrCO3-CaCO3-K2CO3-Na2CO3-Li2CO3 Liquids: New Measurements and a Systematic Trend with Cation Field Strength

    Science.gov (United States)

    Hurt, S. M.; Lange, R. A.; Ai, Y.

    2015-12-01

    The volumetric properties of multi-component carbonate liquids are required to extend thermodynamic models that describe partial melting of the deep mantle (e.g. pMELTS; Ghiorso et al., 2003) to carbonate-bearing lithologies. Carbonate in the mantle is an important reservoir of carbon, which is released to the atmosphere as CO2 through volcanism, and thus contributes to the carbon cycle. Although MgCO3 is the most important carbonate component in the mantle, it is not possible to directly measure the 1-bar density and compressibility of MgCO3 liquid because, like other alkaline-earth carbonates, it decomposes at a temperature lower than its melting temperature. Despite this challenge, Liu and Lange (2003) and O'Leary et al. (2015) showed that the one bar molar volume, thermal expansion and compressibility of the CaCO3 liquid component could be obtained by measuring the density and sound speeds of stable liquids in the CaCO3-Li2CO3-Na2CO3-K2CO3 quaternary system at one bar. In this study, this same strategy is employed on SrCO3- and BaCO3-bearing alkali carbonate liquids. The density and sound speed of seven liquids in the SrCO3-Li2CO3-Na2CO3-K2CO3 quaternary and three liquids in the BaCO3-Li2CO3-Na2CO3-K2CO3 quaternary were measured from 739-1367K, with SrCO3 and BaCO3 concentrations ranging from 10-50 mol%. The density measurements were made using the double-bob Archimedean method and sound speeds were obtained with a frequency-sweep acoustic interferometer. The molar volume and sound speed measurements were used to calculate the isothermal compressibility of each liquid, and the results show the volumetric properties mix ideally with composition. The partial molar volume and compressibility of the SrCO3 and BaCO3 components are compared to those obtained for the CaCO3 component as a function of cation field strength. The results reveal a systematic trend that allows the partial molar volume and compressibility of the MgCO3 liquid component to be estimated.

  2. First identification and thermodynamic characterization of the ternary U(VI) species, UO2(O2)(CO3)2(4-), in UO2-H2O2-K2CO3 solutions.

    Science.gov (United States)

    Goff, George S; Brodnax, Lia F; Cisneros, Michael R; Peper, Shane M; Field, Stephanie E; Scott, Brian L; Runde, Wolfgang H

    2008-03-17

    In alkaline carbonate solutions, hydrogen peroxide can selectively replace one of the carbonate ligands in UO2(CO3)3(4-) to form the ternary mixed U(VI) peroxo-carbonato species UO2(O2)(CO3)2(4-). Orange rectangular plates of K4[UO2(CO3)2(O2)].H2O were isolated and characterized by single crystal X-ray diffraction studies. Crystallographic data: monoclinic, space group P2(1)/ n, a = 6.9670(14) A, b = 9.2158(10) A, c = 18.052(4) A, Z = 4. Spectrophotometric titrations with H 2O 2 were performed in 0.5 M K 2CO 3, with UO2(O2)(CO3)2(4-) concentrations ranging from 0.1 to 0.55 mM. The molar absorptivities (M(-1) cm(-1)) for UO2(CO3)3(4-) and UO2(O2)(CO3)2(4-) were determined to be 23.3 +/- 0.3 at 448.5 nm and 1022.7 +/- 19.0 at 347.5 nm, respectively. Stoichiometric analyses coupled with spectroscopic comparisons between solution and solid state indicate that the stable solution species is UO2(O2)(CO3)2(4-), which has an apparent formation constant of log K' = 4.70 +/- 0.02 relative to the tris-carbonato complex.

  3. Production of activated carbons from waste tyres for low temperature NOx control.

    Science.gov (United States)

    Al-Rahbi, Amal S; Williams, Paul T

    2016-03-01

    Waste tyres were pyrolysed in a bench scale reactor and the product chars were chemically activated with alkali chemical agents, KOH, K2CO3, NaOH and Na2CO3 to produce waste tyre derived activated carbons. The activated carbon products were then examined in terms of their ability to adsorb NOx (NO) at low temperature (25°C) from a simulated industrial process flue gas. This study investigates the influence of surface area and porosity of the carbons produced with the different alkali chemical activating agents on NO capture from the simulated flue gas. The influence of varying the chemical activation conditions on the porous texture and corresponding NO removal from the flue gas was studied. The activated carbon sorbents were characterized in relation to BET surface area, micropore and mesopore volumes and chemical composition. The highest NO removal efficiency for the waste tyre derived activated carbons was ∼75% which was obtained with the adsorbent treated with KOH which correlated with both the highest BET surface area and largest micropore volume. In contrast, the waste tyre derived activated carbons prepared using K2CO3, NaOH and Na2CO3 alkali activating agents appeared to have little influence on NO removal from the flue gases. The results suggest problematic waste tyres, have the potential to be converted to activated carbons with NOx removal efficiency comparable with conventionally produced carbons. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Use of sawdust Eucalyptus sp. in the preparation of activated carbons Utilização de serragem de Eucalyptus sp. na preparação de carvões ativados

    Directory of Open Access Journals (Sweden)

    Gabriela Martucci Couto

    2012-02-01

    Full Text Available Wood sawdust is a solid residue, generated in the timber industry, which is of no profitable use and can cause serious environmental problems if disposed inadequately. The aim of this study was to use the eucalyptus sawdust in the preparation of activated carbons AC and test them as adsorbents of methylene blue (MB and phenol, representative pollutants from aqueous effluents of various industries. The eucalyptus sawdust was characterized by instrumental analysis such as elementary analysis (CHNS-O, thermogravimetric analysis (TGA, infrared spectroscopy (FTIR and scanning electron microscopy (SEM. The activated carbons were prepared by physical activation with carbon dioxide AC_CO2, (10º C min-1, 850º C, 1h and by chemical activation with potassium carbonate AC_K2CO3 (10º C min-1, 850º C, 3h. The AC_CO2 and AC_K2CO3 were characterized by CHN-O, TGA, FTIR, N2 adsorption/desorption (BET to evaluate the specific surface area and SEM. The resulting activated carbons were tested for their ability to adsorb MB and phenol in water. The activated carbons produced in this work were predominantly microporous and showed specific surface area of about 535 m² g-1. The AC_K2CO3 was more effective in the adsorption of MB (81 mg g-1 and phenol (330 mg g-1 than AC_CO2 (32 mg g-1 and 172 mg g-1, respectively, for MB and phenol.A serragem é um resíduo sólido, gerado na indústria madeireira, que não tem uso rentável e pode causar sérios problemas ambientais quando disposta inadequadamente. Neste estudo, objetivou-se utilizar a serragem de eucalipto na preparação de carvões ativados (AC e testá-los como adsorventes do corante azul de metileno (MB e fenol; moléculas que representam poluentes de efluentes industriais. A serragem de eucalipto foi caracterizada por análises instrumentais, tais como: análise elementar (CHNS-O, análise termogravimétrica (TGA, espectroscopia na região do infravermelho (FTIR e microscopia eletrônica de varredura (SEM

  5. Phenol adsorption by activated carbon produced from spent coffee grounds.

    Science.gov (United States)

    Castro, Cínthia S; Abreu, Anelise L; Silva, Carmen L T; Guerreiro, Mário C

    2011-01-01

    The present work highlights the preparation of activated carbons (ACs) using spent coffee grounds, an agricultural residue, as carbon precursor and two different activating agents: water vapor (ACW) and K(2)CO(3) (ACK). These ACs presented the microporous nature and high surface area (620-950 m(2) g(-1)). The carbons, as well as a commercial activated carbon (CAC) used as reference, were evaluated as phenol adsorbent showing high adsorption capacity (≈150 mg g(-1)). The investigation of the pH solution in the phenol adsorption was also performed. The different activating agents led to AC with distinct morphological properties, surface area and chemical composition, although similar phenol adsorption capacity was verified for both prepared carbons. The production of activated carbons from spent coffee grounds resulted in promising adsorbents for phenol removal while giving a noble destination to the residue.

  6. Nuclear activated cw chemical laser

    International Nuclear Information System (INIS)

    Roberts, T.G.

    1982-01-01

    A cw chemical laser which uses processed radioactive waste to produce active atoms from a chemically inactive gas before being mixed with another molecule such as hydrogen or deuterium is disclosed. This laser uses no toxic or corrosive fuels and does not require any electrical or other type of auxiliary power supply. The energy released by the radioactive material is used to produce the active atoms such as fluorine. This is accomplished by using the radiation products from processed radioactive waste to dissociate the inert gas in the plenum of the laser. The radioactive material is held in the passageway walls of a device similar to a heat exchanger. The exchanger device may be located in the gas generator section of a chemical laser. The inactive gas is passed through the exchanger device and while passing through it the radiation from the radioactive material dissociates the gas, producing a concentration of free active atoms. This active atom generator then feeds the nozzle bank or mixing section of a laser to produce a lasing action

  7. Current Chemical Risk Management Activities

    Science.gov (United States)

    EPA's existing chemicals programs address pollution prevention, risk assessment, hazard and exposure assessment and/or characterization, and risk management for chemicals substances in commercial use.

  8. Inorganic chemically active adsorbents (ICAAs)

    Energy Technology Data Exchange (ETDEWEB)

    Ally, M.R. [Oak Ridge National Lab., TN (United States); Tavlarides, L.

    1997-10-01

    Oak Ridge National Laboratory (ORNL) researchers are developing a technology that combines metal chelation extraction technology and synthesis chemistry. They begin with a ceramic substrate such as alumina, titanium oxide or silica gel because they provide high surface area, high mechanical strength, and radiolytic stability. One preparation method involves silylation to hydrophobize the surface, followed by chemisorption of a suitable chelation agent using vapor deposition. Another route attaches newly designed chelating agents through covalent bonding by the use of coupling agents. These approaches provide stable and selective, inorganic chemically active adsorbents (ICAAs) tailored for removal of metals. The technology has the following advantages over ion exchange: (1) higher mechanical strength, (2) higher resistance to radiation fields, (3) higher selectivity for the desired metal ion, (4) no cation exchange, (5) reduced or no interference from accompanying anions, (6) faster kinetics, and (7) easy and selective regeneration. Target waste streams include metal-containing groundwater/process wastewater at ORNL`s Y-12 Plant (multiple metals), Savannah River Site (SRS), Rocky Flats (multiple metals), and Hanford; aqueous mixed wastes at Idaho National Engineering Laboratory (INEL); and scrubber water generated at SRS and INEL. Focus Areas that will benefit from this research include Mixed Waste, and Subsurface Contaminants.

  9. Linking algal growth inhibition to chemical activity

    DEFF Research Database (Denmark)

    Schmidt, Stine N.; Mayer, Philipp

    2015-01-01

    for baseline toxicity. First, the reported effective concentrations (EC50) were divided by the respective water solubilities (Swater), since the obtained EC50/Swater ratio essentially equals the effective chemical activity (Ea50). The majority of EC50/Swater ratios were within the expected chemical activity...

  10. Active carbon supported molybdenum carbides for higher alcohols synthesis from syngas

    DEFF Research Database (Denmark)

    Wu, Qiongxiao; Chiarello, Gian Luca; Christensen, Jakob Munkholt

    This work provides an investigation of the high pressure CO hydrogenation to higher alcohols on K2CO3 promoted active carbon supported molybdenum carbide. Both activity and selectivity to alcohols over supported molybdenum carbides increased significantly compared to bulk carbides in literatures...

  11. Linking algal growth inhibition to chemical activity

    DEFF Research Database (Denmark)

    Schmidt, Stine N.; Mayer, Philipp

    Unitless chemical activity, expressing the energetic level of a compound relative to its energetic level in pure liquid [0-1], has proven useful to quantify the effective exposure to hydrophobic organic compounds through both aerial and aqueous media. Several studies have linked toxicity to chemi......Unitless chemical activity, expressing the energetic level of a compound relative to its energetic level in pure liquid [0-1], has proven useful to quantify the effective exposure to hydrophobic organic compounds through both aerial and aqueous media. Several studies have linked toxicity...... to chemical activity, as opposed to e.g. the total concentration. Baseline toxicity (narcosis) for neutral hydrophobic organic compounds has been shown to initiate in the narrow chemical activity range of 0.01 to 0.1. This presentation focuses on linking algal growth inhibition to chemical activity......-polar liquids were applied to challenge the chemical activity range for baseline toxicity. For each compound, the effective activity (Ea50) was estimated as the ratio of the effective concentration (EC50) and water solubility. Of these ratios, 90% were within the expected chemical activity range of 0.01 to 0...

  12. Molecular activation analysis for chemical speciation studies

    International Nuclear Information System (INIS)

    Chai-Chifang

    1998-01-01

    The term of Molecular Activation Analysis (MAA) refers to an activation analysis method that is able to provide information about the chemical species of elements in system of interests, though its definition has remained to be assigned. Its development is strongly stimulated by the urgent need to know the chemical species of elements, because the total concentrations are often without any meaning when assessing health or environmental risks of trace elements.In practice, the MAA is a combination of conventional instrumental or radiochemical activation analysis and physical, chemical or biochemical separation techniques. The MAA is able to play a particular role in speciation studies. However, the critical point in the MAA is that it is not permitted to change the primitive chemical species of elements in systems, or the change has to be under control; in the meantime it is not allowed to form the 'new artifact' originally not present in systems. Some practical examples of MAA for chemical species research performed recently in our laboratory will be presented as follows: Chemical species of platinum group elements in sediment; Chemical species of iodine in marine algae; Chemical species of mercury in human tissues; Chemical species of selenium in corn; Chemical species of rare earth elements in natural plant, etc. The merits and limitations of MAA will be described as well. (author)

  13. Utilization of chemical derivatives in activation analysis

    International Nuclear Information System (INIS)

    Ehmann, W.D.

    1990-01-01

    Derivative activation analysis (DAA) is a method to enhance the sensitivity of nuclear activation analysis for the more elusive elements. It may also allow a degree of chemical speciation for the element of interest. DAA uses a preirradiation chemical reaction on the sample to initiate the formation of, or an exchange with, a chemical complex which contains a surrogate element, M. As a result, the amount of the element or the chemical species to be determined, X, is now represented by measurement of the amount of the surrogate element, M, that is made part of, or released by the complex species. The surrogate element is selected for its superior properties for nuclear activation analysis and the absence of interference reaction in its final determination by instrumental neutron activation analysis (INAA) after some preconcentration or separation chemistry. Published DAA studies have been limited to neutron activation analysis. DAA can offer the analyst some important advantages. It can determine elements, functional groups, or chemical species which cannot be determined directly by INAA, fast neutron activation analysis (FNAA), prompt gamma neutron activation analysis (PGNAA), or charged particle activation analysis (CPAA) procedures. When compared with conventional RNAA, there are fewer precautions with respect to handling of intensely radioactive samples, since the chemistry is done before the irradiation. The preirradiation chemistry may also eliminate many interferences that might occur in INAA and, through use of an appropriate surrogate element, can place the analytical gamma-ray line in an interference-free region of the gamma-ray spectrum

  14. Molecular activation analysis for chemical species studies

    International Nuclear Information System (INIS)

    Chai Zhifang; Mao Xueying; Wang Yuqi; Sun Jingxin; Qian Qingfang; Hou Xiaolin; Zhang Peiqun; Chen Chunying; Feng Weiyu; Ding Wenjun; Li Xiaolin; Li Chunsheng; Dai Xiongxin

    2001-01-01

    The Molecular Activation Analysis (MAA) mainly refers to an activation analysis method that is able to provide information about the chemical species of elements in systems of interest, though its exact definition has remained to be assigned. Its development is strongly stimulated by the urgent need to know the chemical species of elements, because the bulk contents or concentrations are often insignificant for judging biological, environmental or geochemical effects of elements. In this paper, the features, methodology and limitation of MAA were outlined. Further, the up-to-date MAA progress made in our laboratory was introduced as well. (author)

  15. I2/K2CO3: An efficient catalyst for the synthesis of 5-aryl-2,6-dicyano ...

    Indian Academy of Sciences (India)

    Abstract. Molecular iodine in the presence of potassium carbonate has been found to be an efficient and eco- friendly catalyst for the synthesis of polysubstituted dicyanoanilines from aldehydes, acetone and malononitrile under solvent-free thermal condition. The experimental procedure is simple, includes shorter reaction ...

  16. CHEMICAL COMPOSITION AND ANTIOXIDANT ACTIVITY OF APIS ...

    African Journals Online (AJOL)

    CHEMICAL COMPOSITION AND ANTIOXIDANT ACTIVITY OF APIS. MELLIFERA BEE POLLEN FROM NORTHWEST ALGERIA. A. Rebiai* and T.Lanez. University of El Oued, VTRS Laboratory, P.O. Box 789, 39000, El Oued, Algeria. Received: 08 November 2012 / Accepted: 23 December 2012 / Published online: 31 ...

  17. On chemical activity of heavy metal oxides

    International Nuclear Information System (INIS)

    Mechev, V.V.

    1994-01-01

    Interaction of solid oxides of heavy nonferrous metals with sulfur and carbon is investigated. The results are discussed. Direct dependence of chemical activity of oxides on disordering of their crystal lattice at heating is established. Beginning of interaction in the systems studied is accompanied by change of oxide conductivity type

  18. Foundational aspects of the concept of chemical activity

    DEFF Research Database (Denmark)

    Mayer, Philipp

    2015-01-01

    The chemical activity of an organic chemical quantifies its potential for spontaneous physicochemical processes, such as diffusion, sorption, and partitioning. For instance, the chemical activity of a sediment contaminant determines its equilibrium partitioning concentration in sediment-dwelling ...

  19. Service activities of chemical analysis division

    International Nuclear Information System (INIS)

    Eom, Tae Yoon; Suh, Moo Yul; Park, Kyoung Kyun; Jung, Ki Suk; Joe, Kih Soo; Jee, Kwang Yong; Jung, Woo Sik; Sohn, Se Chul; Yeo, In Heong; Han, Sun Ho

    1988-12-01

    Progress of the Division during the year of 1988 was described on the service activities for various R and D projects carrying out in the Institute, for the fuel fabrication and conversion plant, and for the post-irradiation examination facility. Relevant analytical methodologies developed for the chemical analysis of an irradiated fuel, safeguards chemical analysis, and pool water monitoring were included such as chromatographic separation of lanthanides, polarographic determination of dissolved oxygen in water, and automation on potentiometric titration of uranium. Some of the laboratory manuals revised were also included in this progress report. (Author)

  20. Antimicrobial activity of chemically modified dextran derivatives.

    Science.gov (United States)

    Tuchilus, Cristina G; Nichifor, Marieta; Mocanu, Georgeta; Stanciu, Magdalena C

    2017-04-01

    Cationic amphiphilic dextran derivatives with a long alkyl group attached to the reductive end of the polysaccharide chain and quaternary ammonium groups attached as pendent groups to the main dextran backbone were synthesized and tested for their antimicrobial properties against several bacteria and fungi strains. Dependence of antimicrobial activity on both polymer chemical composition (dextran molar mass, length of end alkyl group and chemical structure of ammonium groups) and type of microbes was highlighted by disc-diffusion method (diameter of inhibition zone) and broth microdilution method (minimum inhibitory concentrations). Polymers had antimicrobial activity for all strains studied, except for Pseudomonas aeruginosa ATCC 27853. The best activity against Staphylococcus aureus (Minimun Inhibitory Concentration 60μg/mL) was provided by polymers obtained from dextran with lower molecular mass (Mn=4500), C 12 H 25 or C 18 H 37 end groups, and N,N-dimethyl-N-benzylammonium pendent groups. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Chemical and physical stability of smectites and illite in electrolyte solutions: experimental study at 150 C

    International Nuclear Information System (INIS)

    Boutiche, M.

    1995-01-01

    Chemical interactions between electrolytic solutions commonly used i drilling muds and clays have been studies under P-T conditions similar to those of drillings (150 deg C) in order to determine the eventual consequences on the stability of clay rich formations. The experimental work has been carried out using several solutions (water, NaOH (pH 8, 10, 12), KCI (0,1, 1 2 mol./l), sea water, and K 2 CO 3 ) and clay minerals with low to high amounts of swelling layers (smectite (Na, Na-Ca, Ca), mixed layered illite-smectite minerals). Run products are studied by X-ray diffraction and electronic microprobe. Smectite layers show series of mineralogical changes (cation exchange in the interlayer site, formation of non-swelling layers, hydrolysis), which, however, do not yield to the formation of new minerals, except in the case of the interaction with K 2 CO 3 at 150 deg C (zeolite crystallisation). Cation exchange in the interlayer depends on the nature of the cation, cation concentration in the solution, exchange constants, and liquid/solid ratio. In dilute solutions ( 1 mol./l), because they favour the collapse of swelling layers, and dispersion. Solutions of K 2 CO 3 at 150 deg C are at the origin of the transformation of smectite to zeolites, and high pH - highly saline solutions are rather aggressive, and would probably not stabilize the argilites. (author)

  2. Chemical reaction on solid surface observed through isotope tracer technique

    International Nuclear Information System (INIS)

    Tanaka, Ken-ichi

    1983-01-01

    In order to know the role of atoms and ions on solid surfaces as the partners participating in elementary processes, the literatures related to the isomerization and hydrogen exchanging reaction of olefines, the hydrogenation of olefines, the metathesis reaction and homologation of olefines based on solid catalysts were reviewed. Various olefines, of which the hydrogen atoms were substituted with deuterium at desired positions, were reacted using various solid catalysts such as ZnO, K 2 CO 3 on C, MoS 2 (single crystal and powder) and molybdenum oxide (with various carriers), and the infra-red spectra of adsorbed olefines on catalysts, the isotope composition of reaction products and the production rate of the reaction products were measured. From the results, the bonding mode of reactant with the atoms and ions on solid surfaces, and the mechanism of the elementary process were considered. The author emphasized that the mechanism of the chemical reaction on solid surfaces and the role of active points or catalysts can be made clear to the considerable extent by combining isotopes suitably. (Yoshitake, I.)

  3. Quantum Chemical and Experimental Studies on the Mechanism of Alkylation of β-Dicarbonyl Compounds. The Synthesis of Five and Six Membered Heterocyclic Spiro Derivatives

    Directory of Open Access Journals (Sweden)

    Ali Hüseyinli

    2004-11-01

    Full Text Available The alkylation of β-dicarbonyl compounds in a K2CO3/DMSO system wasfound to afford O- and C-alkylated derivatives, depending on the type of the β-dicarbonylcompound involved. The alkyl derivatives obtained were used in the synthesis of some newspiro barbituric acid derivatives. Quantum chemical calculations were carried out toelucidate the reaction mechanisms for some typical synthesis.

  4. Chemical Composition, antioxidant activity, functional properties and ...

    African Journals Online (AJOL)

    Chemical Composition, antioxidant activity, functional properties and inhibitory action of unripe plantain ( M. Paradisiacae ) flour. ... of dry matter (48.00 ± 3.96%) and starch (31.10 ± 0.44%) but was low in phenol (1.42 ± 0.03%), protein (3.15 ± 0.042%), ash (5.50 ± 0.42%) and total soluble sugar (0.64 ± 0.001%) (p < 0.05).

  5. Preparation and characterization of activated carbon from castor de-oiled cake

    Directory of Open Access Journals (Sweden)

    Viviana M. Ospina-Guarín

    2014-01-01

    Full Text Available Biomass residues have been used to produce activated carbons. On this process, the activation method and the raw composition determine the properties as porosity and surface area of the charcoal. After the extraction of castor oil, there is a solid byproduct (cake of low added value, which was used in the production of activated carbon to add value to this waste. For this purpose two traditional methods were used, first, physical activation using as activating agents steam, CO2 and mixture of both, and additionally chemical activation using K2CO3 as the activating agent. Some activated carbons were characterized using N2 adsorption isotherms, BET surface areas varied between 255.98 (m2/g and 1218.43 (m2/g. By SEM and EDS analysis was possible to observe that materials obtained by the two types of activation are principally amorphous and morphological characteristics of the carbon obtained by physical activation are very different from those obtained by chemical activation. Finally, through impregnation of inorganic phases of Ni and Mo was revealed that the high dispersion characteristics, these carbonaceous materials will have potential to be used as catalyst support.

  6. Activation and chemical analysis of drinking waters

    International Nuclear Information System (INIS)

    Sharma, H.K.; Mittal, V.K.; Sahota, H.S.

    1989-01-01

    Ground water samples from Patiala city have been analysed for 22 trace elements using neutron activation analysis and for seven chemical parameters using standard techniques. It was found that alkali and alkaline earth metals have high concentrations in all samples whereas the concentrations of toxic metals are low in the majority of samples. However, chromium and cadmium concentrations are higher in ground water taken from the industrial belt of the city. This indicates that the overall level of pollution is low, but that some measures are still needed to inhibit various industries from polluting the ground water. (author)

  7. Textural characterization and chemistry of activated coal obtained starting from stone of African palm at different conditions of temperature and carbonization time

    International Nuclear Information System (INIS)

    Diaz, Claudia Marcela; Briceno, Nelson; Baquero, Maria Cristina; Giraldo, Liliana; Moreno, Juan Carlos

    2002-01-01

    Activated carbons are obtained starting from stone of African palm, by means of chemical activation with k 2 CO 3 and thermal activation with CO 2 . The initial material undergoes different conditions of carbonization temperature 600, 750 and 900 Celsius degrades and different times of carbonization 1.0; 1.5; 2.0 and 2.5 hours, with the objective of observing how these conditions affect the porosity of the material. It is observed a low development of the porosity in the carbons carbonized to 900 Celsius degrade and activated chemically. The acidity and basicity are determined for each one of the activated carbons obtained for titration with solutions 0.05 m of sodium hydroxide and of hydrochloric acid respectively. The samples activated chemically present bigger contents of acid groups, for the experimental conditions of work? Than the samples obtained by thermal activation for the activated carbons thermally activated, the values for acid and basic groups are low-between 0,20 and 0,72 meq g-l

  8. Plants and chemical constituents with giardicidal activity

    Directory of Open Access Journals (Sweden)

    Flavia M.M. Amaral

    Full Text Available Intestinal infection caused by Giardia lamblia represents a serious public health problem, with increased rates of prevalence in numerous countries. Increased resistance of the parasite and the side-effects of the reference drugs employed in the treatment of giardiasis make necessary to seek new therapeutic agents. Natural products, especially of plant origin, represent excellent starting point for research. The objective of this study is to review the literature on plant extracts, fractions and chemical constituents whose giardicidal activity has been investigated in vitro. The review describes 153 (one hundred and fifty-three plant species from 69 (sixty-nine families that were evaluated for their giardicidal activity. The geographical distribution of the plant species, the part used, preparation, strain of Giardia lamblia tested and the results obtained by the authors are also given. One hundred and one compounds isolated from plant species, classified by chemical class, are presented. Recent aspects of research on natural products of plant origin employed in the treatment of giardiasis are also discussed.

  9. A Chemical Activity Approach to Exposure and Risk Assessment of Chemicals

    DEFF Research Database (Denmark)

    Gobas, Frank A. P. C.; Mayer, Philipp; Parkerton, Thomas F.

    2018-01-01

    activity approach, its strengths and limitations, and provides examples of how this concept may be applied to the management of single chemicals and chemical mixtures. The examples demonstrate that the chemical activity approach provides a useful framework for 1) compiling and evaluating exposure......To support the goals articulated in the vision for exposure and risk assessment in the twenty-first century, we highlight the application of a thermodynamic chemical activity approach for the exposure and risk assessment of chemicals in the environment. The present article describes the chemical...... assessment. The article further illustrates that the chemical activity approach can support an adaptive management strategy for environmental stewardship of chemicals where “safe” chemical activities are established based on toxicological studies and presented as guidelines for environmental quality...

  10. Stability of a chemically active floating disk

    Science.gov (United States)

    Vandadi, Vahid; Jafari Kang, Saeed; Rothstein, Jonathan; Masoud, Hassan

    2017-11-01

    We theoretically study the translational stability of a chemically active disk located at a flat liquid-gas interface. The initially immobile circular disk uniformly releases an interface-active agent that locally changes the surface tension and is insoluble in the bulk. If left unperturbed, the stationary disk remains motionless as the agent is discharged. Neglecting the inertial effects, we numerically test whether a perturbation in the translational velocity of the disk can lead to its spontaneous and self-sustained motion. Such a perturbation gives rise to an asymmetric distribution of the released factor that could trigger and sustain the Marangoni propulsion of the disk. An implicit Fourier-Chebyshev spectral method is employed to solve the advection-diffusion equation for the concentration of the active agent. The solution, given a linear equation of state for the surface tension, provides the shear stress distribution at the interface. This and the no-slip condition on the wetted surface of the disk are then used at each time step to semi-analytically determine the Stokes flow in the semi-infinite liquid layer. Overall, the findings of our investigation pave the way for pinpointing the conditions under which interface-bound active particles become dynamically unstable.

  11. HDO of guaiacol over NiMo catalyst supported on activated carbon derived from castor de-oiled cake

    Directory of Open Access Journals (Sweden)

    Viviana Ospina

    2015-05-01

    Full Text Available Physical and chemical activation methods were used to prepare two different activated carbons (ACs from castor de-oiled cake. H2O/CO2 mixture was used as the physical activating agent, and for chemical activation potassium carbonate (K2CO3 was used. For both materials, textural and chemical properties were characterized by N2 adsorption–desorption isotherms, thermogravimetric analysis (TGA, Fourier Transform Infrared Spectroscopy (FTIR, thermal programmed reduction (TPR, X-ray fluorescence (XRF, and scanning electron microscopy (SEM. The ACs were used as supports for NiMo sulfide catalysts, which were prepared by wetness impregnation and in-situ sulfided for the hydrodeoxygenation (HDO of guaiacol (GUA as a model compound of bio-oil. The HDO reaction was carried out in a typical batch reactor at 5 MPa of H2 and 350 °C. Under the same test conditions, commercial catalysts were also tested in the reaction. Although the commercial catalysts displayed higher GUA conversion, the prepared catalysts showed higher activity and non-oxygenated and saturated products yield.

  12. Utilization of Cacao Pod Husk (Theobroma cacao l.) as Activated Carbon and Catalyst in Biodiesel Production Process from Waste Cooking Oil

    Science.gov (United States)

    Rachmat, Devita; Johar Mawarani, Lizda; Dewi Risanti, Doty

    2018-01-01

    Cocoa pod husk (Theobroma cacao l.) is a waste from cocoa beans processing. In this research we employ cocoa pod husk as activated carbon to decrease the value of FFA (Free Fatty Acid) in waste cooking oil and as K2CO3 catalyst in biodiesel production process from waste cooking oil. Cocoa pod husk was crusched and grounded into powder that passed thorugh 60 mesh-screen. As activated carbon, cocoa pod husk was firstly carbonized at three variant temperatures i.e 250°C, 300°C and 350°C. The activation process was done using HCl 2M as activator. Based on the results of XRD and FTIR, the carbonization at all variant temperatures does not cause a significant changes in terms of crystallite structure and water content. The pore of activated carbon started to form in sample that was carbonized at 350°C resulting in pore diameter of 5.14644 nm. This result was supported by the fact that the ability of this activated carbon in reducing the FFA of waste cooking oil was the most pronounced one, i.e. up to 86.7% of FFA. It was found that the performance of cocoa pod husk’s activated carbon in reducing FFA is more effective than esterification using H2SO4 which can only decrease 80.8%. On the other hand, the utilization as K2CO3 catalyst was carried out by carbonization at temperature 650°C and extraction using aquadest solvent. The extraction of cocoa pod husk produced 7.067% K2CO3 catalyst. According to RD results the fraction of K2CO3 compound from the green catalysts is the same as the commercial (SAP, 99%) that is ≥ 60%. From the obtained results, the best yield percentage was obtained using K2CO3 catalyst from cacao pod husk extract, i.e. 73-85%. To cope with biodiesel conversion efficiency, a two-step process consisting pretreatment with activated carbon carbonized at 350°C and esterification with K2CO3 from cocoa pod husk catalyst was developed. This two-step process could reach a high conversion of 85%. From the results it was clear that the produced

  13. The use of simultaneous chemical precipitation in modified activated ...

    African Journals Online (AJOL)

    The use of simultaneous chemical precipitation in modified activated sludge systems exhibiting biological excess phosphate removal: Part 6: Modelling of simultaneous chemical-biological P removal - review of existing models.

  14. Chemical constituents and antimicrobial activity of Goniothalamus ...

    African Journals Online (AJOL)

    The essential oils from the twig and root of Goniothalamus macrophyllus were obtained by hydrodistillation and subjected to Gas Chromatography (GC-FID) and Gas Chromatography/Mass Spectrometry (GC-MS) using CBP-5 capillary column in order to determine their chemical composition. Both twig and root oils and four ...

  15. TSCA Chemical Data Reporting Fact Sheet: Reporting Manufactured Chemical Substances from Metal Mining and Related Activities

    Science.gov (United States)

    This fact sheet provides guidance on the Chemical Data Reporting (CDR) rule requirements related to the reporting of mined metals, intermediates, and byproducts manufactured during metal mining and related activities.

  16. anti-inflammatory and analgesic activities: chemical constituents of ...

    African Journals Online (AJOL)

    a

    *Corresponding author. E-mail: bedisag@yahoo.fr. ANTI-INFLAMMATORY AND ANALGESIC ACTIVITIES: CHEMICAL CONSTITUENTS OF ESSENTIAL OILS OF OCIMUM GRATISSIMUM,. EUCALYPTUS CITRIODORA AND CYMBOPOGON GIGANTEUS INHIBITED. LIPOXYGENASE L-1 AND CYCLOOXYGENASE OF ...

  17. Active disturbance rejection controller for chemical reactor

    International Nuclear Information System (INIS)

    Both, Roxana; Dulf, Eva H.; Muresan, Cristina I.

    2015-01-01

    In the petrochemical industry, the synthesis of 2 ethyl-hexanol-oxo-alcohols (plasticizers alcohol) is of high importance, being achieved through hydrogenation of 2 ethyl-hexenal inside catalytic trickle bed three-phase reactors. For this type of processes the use of advanced control strategies is suitable due to their nonlinear behavior and extreme sensitivity to load changes and other disturbances. Due to the complexity of the mathematical model an approach was to use a simple linear model of the process in combination with an advanced control algorithm which takes into account the model uncertainties, the disturbances and command signal limitations like robust control. However the resulting controller is complex, involving cost effective hardware. This paper proposes a simple integer-order control scheme using a linear model of the process, based on active disturbance rejection method. By treating the model dynamics as a common disturbance and actively rejecting it, active disturbance rejection control (ADRC) can achieve the desired response. Simulation results are provided to demonstrate the effectiveness of the proposed method

  18. Active disturbance rejection controller for chemical reactor

    Energy Technology Data Exchange (ETDEWEB)

    Both, Roxana; Dulf, Eva H.; Muresan, Cristina I., E-mail: roxana.both@aut.utcluj.ro [Technical University of Cluj-Napoca, 400114 Cluj-Napoca (Romania)

    2015-03-10

    In the petrochemical industry, the synthesis of 2 ethyl-hexanol-oxo-alcohols (plasticizers alcohol) is of high importance, being achieved through hydrogenation of 2 ethyl-hexenal inside catalytic trickle bed three-phase reactors. For this type of processes the use of advanced control strategies is suitable due to their nonlinear behavior and extreme sensitivity to load changes and other disturbances. Due to the complexity of the mathematical model an approach was to use a simple linear model of the process in combination with an advanced control algorithm which takes into account the model uncertainties, the disturbances and command signal limitations like robust control. However the resulting controller is complex, involving cost effective hardware. This paper proposes a simple integer-order control scheme using a linear model of the process, based on active disturbance rejection method. By treating the model dynamics as a common disturbance and actively rejecting it, active disturbance rejection control (ADRC) can achieve the desired response. Simulation results are provided to demonstrate the effectiveness of the proposed method.

  19. Chemical activation of gasification carbon residue for phosphate removal

    Science.gov (United States)

    Kilpimaa, Sari; Runtti, Hanna; Lassi, Ulla; Kuokkanen, Toivo

    2012-05-01

    Recycling of waste materials provides an economical and environmentally significant method to reduce the amount of waste. Bioash formed in the gasification process possesses a notable amount of unburned carbon and therefore it can be called a carbon residue. After chemical activation carbon residue could be use to replace activated carbon for example in wastewater purification processes. The effect of chemical activation process variables such as chemical agents and contact time in the chemical activation process were investigated. This study also explored the effectiveness of the chemically activated carbon residue for the removal of phosphate from an aqueous solution. The experimental adsorption study was performed in a batch reactor and the influence of adsorption time, initial phosphate concentration and pH was studied. Due to the carbon residue's low cost and high adsorption capacity, this type of waste has the potential to be utilised for the cost-effective removal of phosphate from wastewaters. Potential adsorbents could be prepared from these carbonaceous by-products and used as an adsorbent for phosphate removal.

  20. Quantitative genetic activity graphical profiles for use in chemical evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Waters, M.D. [Environmental Protection Agency, Washington, DC (United States); Stack, H.F.; Garrett, N.E.; Jackson, M.A. [Environmental Health Research and Testing, Inc., Research Triangle Park, NC (United States)

    1990-12-31

    A graphic approach, terms a Genetic Activity Profile (GAP), was developed to display a matrix of data on the genetic and related effects of selected chemical agents. The profiles provide a visual overview of the quantitative (doses) and qualitative (test results) data for each chemical. Either the lowest effective dose or highest ineffective dose is recorded for each agent and bioassay. Up to 200 different test systems are represented across the GAP. Bioassay systems are organized according to the phylogeny of the test organisms and the end points of genetic activity. The methodology for producing and evaluating genetic activity profile was developed in collaboration with the International Agency for Research on Cancer (IARC). Data on individual chemicals were compiles by IARC and by the US Environmental Protection Agency (EPA). Data are available on 343 compounds selected from volumes 1-53 of the IARC Monographs and on 115 compounds identified as Superfund Priority Substances. Software to display the GAPs on an IBM-compatible personal computer is available from the authors. Structurally similar compounds frequently display qualitatively and quantitatively similar profiles of genetic activity. Through examination of the patterns of GAPs of pairs and groups of chemicals, it is possible to make more informed decisions regarding the selection of test batteries to be used in evaluation of chemical analogs. GAPs provided useful data for development of weight-of-evidence hazard ranking schemes. Also, some knowledge of the potential genetic activity of complex environmental mixtures may be gained from an assessment of the genetic activity profiles of component chemicals. The fundamental techniques and computer programs devised for the GAP database may be used to develop similar databases in other disciplines. 36 refs., 2 figs.

  1. Development of activated carbon pore structure via physical and chemical activation of biomass fibre waste

    International Nuclear Information System (INIS)

    Williams, Paul T.; Reed, Anton R.

    2006-01-01

    Biomass waste in the form of biomass flax fibre, produced as a by-product of the textile industry was processed via both physical and chemical activation to produce activated carbons. The surface area of the physically activated carbons were up to 840 m 2 g -1 and the carbons were of mesoporous structure. Chemical activation using zinc chloride produced high surface area activated carbons up to 2400 m 2 g -1 and the pore size distribution was mainly microporous. However, the process conditions of temperature and zinc chloride concentration could be used to manipulate the surface area and porosity of the carbons to produce microporous, mesoporous and mixed microporous/mesoporous activated carbons. The physically activated carbons were found to be a mixture of Type I and Type IV carbons and the chemically activated carbons were found to be mainly Type I carbons. The development of surface morphology of physically and chemically activated carbons observed via scanning electron microscopy showed that physical activation produced activated carbons with a nodular and pitted surface morphology whereas activated carbons produced through chemical activation had a smooth surface morphology. Transmission electron microscopy analysis could identify mesopore structures in the physically activated carbon and microporous structures in the chemically activated carbons

  2. Chloride Ingress in Chemically Activated Calcined Clay-Based Cement

    Directory of Open Access Journals (Sweden)

    Joseph Mwiti Marangu

    2018-01-01

    Full Text Available Chloride-laden environments pose serious durability concerns in cement based materials. This paper presents the findings of chloride ingress in chemically activated calcined Clay-Ordinary Portland Cement blended mortars. Results are also presented for compressive strength development and porosity tests. Sampled clays were incinerated at a temperature of 800°C for 4 hours. The resultant calcined clay was blended with Ordinary Portland Cement (OPC at replacement level of 35% by mass of OPC to make test cement labeled PCC35. Mortar prisms measuring 40 mm × 40 mm × 160 mm were cast using PCC35 with 0.5 M Na2SO4 solution as a chemical activator instead of water. Compressive strength was determined at 28th day of curing. As a control, OPC, Portland Pozzolana Cement (PPC, and PCC35 were similarly investigated without use of activator. After the 28th day of curing, mortar specimens were subjected to accelerated chloride ingress, porosity, compressive strength tests, and chloride profiling. Subsequently, apparent diffusion coefficients (Dapp were estimated from solutions to Fick’s second law of diffusion. Compressive strength increased after exposure to the chloride rich media in all cement categories. Chemically activated PCC35 exhibited higher compressive strength compared to nonactivated PCC35. However, chemically activated PCC35 had the least gain in compressive strength, lower porosity, and lower chloride ingress in terms of Dapp, compared to OPC, PPC, and nonactivated PCC35.

  3. Chemical profiling and antioxidant activity of Bolivian propolis.

    Science.gov (United States)

    Nina, Nélida; Quispe, Cristina; Jiménez-Aspee, Felipe; Theoduloz, Cristina; Giménez, Alberto; Schmeda-Hirschmann, Guillermo

    2016-04-01

    Propolis is a relevant research subject worldwide. However, there is no information so far on Bolivian propolis. Ten propolis samples were collected from regions with high biodiversity in the main honey production places in Bolivia and were analyzed for their total phenolics (TP), flavonoids (TF) and antioxidant activity. The chemical profiles of the samples were assessed by TLC, HPLC-DAD, HPLC-DAD-MS/MS(n) and NMR analysis. TP, TF, TLC and NMR analysis showed significant chemical differences between the samples. Isolation of the main constituents by chromatography and identification by HPLC-DAD-MS/MS(n) achieved more than 35 constituents. According to their profiles, the Bolivian propolis can be classified into phenolic-rich and triterpene-rich samples. Propolis from the valleys (Cochabamba, Chuquisaca and Tarija) contained mainly prenylated phenylpropanoids, while samples from La Paz and Santa Cruz contained cycloartane and pentacyclic triterpenes. Phenolic-rich samples presented moderate to strong antioxidant activity while the triterpene-rich propolis were weakly active. High chemical diversity and differential antioxidant effects were found in Bolivian propolis. Our results provide additional evidence on the chemical composition and bioactivity of South American propolis. © 2015 Society of Chemical Industry.

  4. CFD simulation of CO_2 sorption on K_2CO_3 solid sorbent in novel high flux circulating-turbulent fluidized bed riser: Parametric statistical experimental design study

    International Nuclear Information System (INIS)

    Thummakul, Theeranan; Gidaspow, Dimitri; Piumsomboon, Pornpote; Chalermsinsuwan, Benjapon

    2017-01-01

    Highlights: • Circulating-turbulent fluidization was proved to be advantage on CO_2 sorption. • The novel regime was proven to capture CO_2 higher than the conventional regimes. • Uniform solid particle distribution was observed in the novel fluidization regime. • The system continuity had more effect in the system than the process system mixing. • Parametric experimental design analysis was studied to evaluate significant factor. - Abstract: In this study a high flux circulating-turbulent fluidized bed (CTFB) riser was confirmed to be advantageous for carbon dioxide (CO_2) sorption on a potassium carbonate solid sorbent. The effect of various parameters on the CO_2 removal level was evaluated using a statistical experimental design. The most appropriate fluidization regime was found to occur between the turbulent and fast fluidization regimes, which was shown to capture CO_2 more efficiently than conventional fluidization regimes. The highest CO_2 sorption level was 93.4% under optimized CTFB operating conditions. The important parameters for CO_2 capture were the inlet gas velocity and the interactions between the CO_2 concentration and the inlet gas velocity and water vapor concentration. The CTFB regime had a high and uniform solid particle distribution in both the axial and radial system directions and could transport the solid sorbent to the regeneration reactor. In addition, the process system continuity had a stronger effect on the CO_2 removal level in the system than the process system mixing.

  5. Synthesis and optical properties of SiO2–Al2O3–MgO–K2CO3–CaO ...

    Indian Academy of Sciences (India)

    X-ray diffraction analysis is used to confirm the amorphous nature of the prepared glasses. Structures of glasses were studied by using UV–Vis and Fourier transforms infrared ... in weight ratio has been reported for dental CAD/CAM.

  6. Production and characterization of H3BO3-Li2CO3-K2CO3-MgO for dosimetry

    International Nuclear Information System (INIS)

    Marini, Andrea; Ciolini, Riccardo; Souza, Susana O.; Valenca, Joao V.B.; Oliveira, Raquel A.P.; D'Enrrico, Francesco

    2014-01-01

    This work examines a borate glass produced with oxides of potassium and lithium, known as LKB. The suitability of borate glasses for thermoluminescent (TL) dosimetry has been reported in previous studies. In particular, borate glasses doped with different elements showed good characteristics in terms of linearity, sensitivity and effective atomic number. However, borate glasses are also known to have high hygroscopicity, which can reduce the sensitivity of a dosimeter. Contrary to previous studies, in this work, Mg was used as one of the main components of the glass composition. Mg is known to improve the stability of the glass, since it reduces the mobility of the alkali ions and can thus reduce the hygroscopicity of the LKB glass. Three compositions containing 0, 5 and 11 mol% of magnesium oxide were examined in order to determine the effect of magnesium specifically on luminescence, high-temperature resistance and hygroscopicity of LKB glass. The LKB glass with 11 mol% of Mg showed favorable characteristics for the production of dosimeters

  7. Synthesis of Mixed Carbonates via a Three-Component Coupling of Alcohols, CO2, and Alkyl Halides in the Presence of K2CO3 and Tetrabutylammonium Iodide

    Directory of Open Access Journals (Sweden)

    Yu-Mei Shen

    2002-04-01

    Full Text Available Various mixed carbonates can be conveniently prepared in good yields using the corresponding alcohols, alkyl halides under CO2 atmosphere in the presence of potassium carbonate or sodium carbonate and tetrabutylammonium iodide.

  8. Synthesis of Mixed Carbonates via a Three-Component Coupling of Alcohols, CO2, and Alkyl Halides in the Presence of K2CO3 and Tetrabutylammonium Iodide

    OpenAIRE

    Yu-Mei Shen; Min Shi

    2002-01-01

    Various mixed carbonates can be conveniently prepared in good yields using the corresponding alcohols, alkyl halides under CO2 atmosphere in the presence of potassium carbonate or sodium carbonate and tetrabutylammonium iodide.

  9. Chemical composition and larvicidal activity of Zanthoxylum gilletii ...

    African Journals Online (AJOL)

    The essential oil was extracted by hydro-distillation, and its chemical compositions determined by gas chromatography mass spectrometry. The oil was dominated by sesquiterpenes and monoterpenes which accounted for 38.30 and 34.00%, respectively. The oil showed good activity against A. gambiae and recorded LC50 ...

  10. Short Communication: Studies of antimicrobial activity and chemical ...

    African Journals Online (AJOL)

    Chemical constituents of the extract were also determined. The extract of was active against the test organisms including Escherischia coli, Pseudomonas aeruginosa and Candida albicans. Tannins, flavonoids, alkaloids, saponins, anthrax-quinones, starch, general glycosides and bitter principles were found to be present ...

  11. Chemical Composition and Insecticidal Activity of the Essential Oil of ...

    African Journals Online (AJOL)

    Purpose: To investigate the chemical composition and insecticidal activity of the essential oil of the aerial parts of Ostericum grosseserratum against the maize weevil, Sitophilus zeamaisD. Methods: Steam distillation of the aerial parts of O. grosseserratum during the flowering stage was carried out using a Clavenger ...

  12. The use of simultaneous chemical precipitation in modified activated ...

    African Journals Online (AJOL)

    The IAWQ Activated Sludge Model (ASM) No. 2 is a kinetic-based model and incorporates two simple processes for chemical precipitation and redissolution that are readily integrated with biological processes for carbon, nitrogen and phosphorus removal. This model was applied to experimental data collected as part of this ...

  13. Physio-chemical evaluation and biological activity of Ajuga ...

    African Journals Online (AJOL)

    Physio-chemical evaluation and biological activity of Ajuga bracteosa wall and Viola odoroto Linn. Anwar Ali Shad, M. Zeeshan, Hina Fazal, Hamid Ullah Shah, Shabir Ahmed, Hasem Abeer, E. F. Abd_Allah, Riaz Ullah, Hamid Afridi, Akash tariq, Muhammad Adnan Asma ...

  14. Chemical Components and Cardiovascular Activities of Valeriana spp.

    Directory of Open Access Journals (Sweden)

    Heng-Wen Chen

    2015-01-01

    Full Text Available Valeriana spp. is a flowering plant that is well known for its essential oils, iridoid compounds such as monoterpenes and sesquiterpenes, flavonoids, alkaloids, amino acids, and lignanoids. Valeriana spp. exhibits a wide range of biological activities such as lowering blood pressure and heart rate, antimyocardial ischemia reperfusion injury, antiarrhythmia, and regulation of blood lipid levels. This review focuses on the chemical constituents and cardiovascular activities of Valeriana spp.

  15. Structure activity relationships to assess new chemicals under TSCA

    Energy Technology Data Exchange (ETDEWEB)

    Auletta, A.E. [Environmental Protection Agency, Washington, DC (United States)

    1990-12-31

    Under Section 5 of the Toxic Substances Control Act (TSCA), manufacturers must notify the US Environmental Protection Agency (EPA) 90 days before manufacturing, processing, or importing a new chemical substance. This is referred to as a premanufacture notice (PMN). The PMN must contain certain information including chemical identity, production volume, proposed uses, estimates of exposure and release, and any health or environmental test data that are available to the submitter. Because there is no explicit statutory authority that requires testing of new chemicals prior to their entry into the market, most PMNs are submitted with little or no data. As a result, EPA has developed special techniques for hazard assessment of PMN chemicals. These include (1) evaluation of available data on the chemical itself, (2) evaluation of data on analogues of the PMN, or evaluation of data on metabolites or analogues of metabolites of the PMN, (3) use of quantitative structure activity relationships (QSARs), and (4) knowledge and judgement of scientific assessors in the interpretation and integration of the information developed in the course of the assessment. This approach to evaluating potential hazards of new chemicals is used to identify those that are most in need of addition review of further testing. It should not be viewed as a replacement for testing. 4 tabs.

  16. Activation and chemical analysis of drinking water from shallow aquifers

    International Nuclear Information System (INIS)

    Sharma, H.K.; Mittal, V.K.; Sahota, H.S.

    1991-01-01

    In most of the Indian cities drinking water is drawn from shallow aqiufers with the help of hand pumps. These shallow aquifers get easilyl polluted. In the present work we have measured 20 trace elements using Neutron Activation Analysis (NAA) and 8 chemical parameters using standard chemical methods of drinking water drawn from Rajpura city. It was found that almost all water samples are highly polluted. We attribute this to unplaned disposal of industrial and domestic waste over a period of many decades. (author) 11 refs.; 1 fig.; 1 tab

  17. Activation analysis. A basis for chemical similarity and classification

    Energy Technology Data Exchange (ETDEWEB)

    Beeck, J OP de [Ghent Rijksuniversiteit (Belgium). Instituut voor Kernwetenschappen

    1977-01-01

    It is shown that activation analysis is especially suited to serve as a basis for determining the chemical similarity between samples defined by their trace-element concentration patterns. The general problem of classification and identification is discussed. The nature of possible classification structures and their appropriate clustering strategies is considered. A practical computer method is suggested and its application as well as the graphical representation of classification results are given. The possibility for classification using information theory is mentioned. Classification of chemical elements is discussed and practically realized after Hadamard transformation of the concentration variation patterns in a series of samples.

  18. [Chemical Constituents in hypoglycemic active fraction of Celastrus orbiculatus leaf].

    Science.gov (United States)

    Yu, Xiao-xia; Zhang, Ting-ting; Wang, Ding-yong

    2014-06-01

    To study the chemical constituents in the hypoglycemic active fraction of Celastrus orbiculatus leaf. The constituents were separated and purified by column chromatography and thin layer chromatography, and their structures were elucidated by IR, MS and NMR. Seven compounds were isolated from the active fraction of Celastnrus orbiculatus, which identified as kaempferol( 1) ,quercetin(2), kaempferol-7-0-α-L-rhamnoside (3), kaempferol-3,7-di-O-α-L-rhamnoside (4) , quercetin-3-0-β-D-glucoside(5), myricetrin(6) and kaempferol-3-0-rutinoside(7). Chemical constituents in the hypoglycemic active fraction of Celastrus orbiculatus leaf are reported for the first time,and compounds 5,6 and 7 are firstly obtained from this plant.

  19. Optimization of chemical regeneration procedures of spent activated carbon

    Directory of Open Access Journals (Sweden)

    Naser Ghasemzadeh

    2017-01-01

    Full Text Available The chemical regeneration of granular activated carbon exhausted in a petrochemical wastewater unit was investigated. Gas chromatography and energy-dispersive X-ray spectroscopy demonstrated that spent activated carbon carries large types of organic and inorganic materials. Diverse chemical solvents were adopted in comparison with traditional chemical solvents and regeneration efficiency was investigated for each approach. The optimum procedure and optimum condition including temperature, concentration of solvent, and time were determined. The regenerated activated carbon was used in the adsorption of methylene blue (MB in order to find its regeneration efficiency. The regeneration efficiency can be identified by comparing of amount of MB absorbed by the fresh and regenerated activated carbon. The best acidic regenerator was hydrofluoric acid. The higher the temperature causes the faster desorption rate and consequently, the higher regeneration efficiency. The regeneration efficiency increased by means of an increase in the time of regeneration and solvent concentration, but there was an optimum time and solvent concentration for regeneration. The optimum temperature, solvent concentration and regeneration time obtained was 80 ⁰C, 3 molar and 3 hours, respectively.

  20. Improved chemical radioprotection following activation with dextran sulfate

    International Nuclear Information System (INIS)

    Bartonickova, A.; Vacek, A.; Rotkovska, D.

    1982-01-01

    The radioresistance was observed of mice after sublethal and lethal gamma irradiation following a combined application of dextran sulphate and the chemical radioprotectors cystamine and mexamine. The mechanism of the radioprotection by mexamine and cystamine is connected with their effect on the oxygen tension in tissues. With the application of dextran sulphate an increase was observed in metabolic activity of tissues and a reduced oxygen tension in the medium will result in a deeper cell hypoxia in the tissue. (M.D.)

  1. Wound healing activity and chemical standardization of Eugenia pruniformis Cambess

    OpenAIRE

    Ricardo Diego Duarte Galhardo de Albuquerque; Jamila Alessandra Perini; Daniel Escorsim Machado; Thaís Angeli-Gamba; Ricardo dos Santos Esteves; Marcelo Guerra Santos; Adriana Passos Oliveira; Leandro Rocha

    2016-01-01

    Background: Eugenia pruniformis is an endemic species from Brazil. Eugenia genus has flavonoids as one of the remarkable chemical classes which are related to the improvement of the healing process. Aims: To evaluate of wound healing activity of E. pruniformis leaves and to identify and quantify its main flavonoids compounds. Materials And Methods: Wound excision model in rats was used to verify the hydroethanolic and ethyl acetate extracts potential. The animals were divided in four groups o...

  2. Insect-gene-activity detection system for chemical and biological warfare agents and toxic industrial chemicals

    Science.gov (United States)

    Mackie, Ryan S.; Schilling, Amanda S.; Lopez, Arturo M.; Rayms-Keller, Alfredo

    2002-02-01

    Detection of multiple chemical and biological weapons (CBW) agents and/or complex mixtures of toxic industrial chemicals (TIC) is imperative for both the commercial and military sectors. In a military scenario, a multi-CBW attack would create confusion, thereby delaying decontamination and therapeutic efforts. In the commercial sector, polluted sites invariably contain a mixture of TIC. Novel detection systems capable of detecting CBW and TIC are sorely needed. While it may be impossible to build a detector capable of discriminating all the possible combinations of CBW, a detection system capable of statistically predicting the most likely composition of a given mixture is within the reach of current emerging technologies. Aquatic insect-gene activity may prove to be a sensitive, discriminating, and elegant paradigm for the detection of CBW and TIC. We propose to systematically establish the expression patterns of selected protein markers in insects exposed to specific mixtures of chemical and biological warfare agents to generate a library of biosignatures of exposure. The predicting capabilities of an operational library of biosignatures of exposures will allow the detection of emerging novel or genetically engineered agents, as well as complex mixtures of chemical and biological weapons agents. CBW and TIC are discussed in the context of war, terrorism, and pollution.

  3. Mining Chemical Activity Status from High-Throughput Screening Assays

    KAUST Repository

    Soufan, Othman

    2015-12-14

    High-throughput screening (HTS) experiments provide a valuable resource that reports biological activity of numerous chemical compounds relative to their molecular targets. Building computational models that accurately predict such activity status (active vs. inactive) in specific assays is a challenging task given the large volume of data and frequently small proportion of active compounds relative to the inactive ones. We developed a method, DRAMOTE, to predict activity status of chemical compounds in HTP activity assays. For a class of HTP assays, our method achieves considerably better results than the current state-of-the-art-solutions. We achieved this by modification of a minority oversampling technique. To demonstrate that DRAMOTE is performing better than the other methods, we performed a comprehensive comparison analysis with several other methods and evaluated them on data from 11 PubChem assays through 1,350 experiments that involved approximately 500,000 interactions between chemicals and their target proteins. As an example of potential use, we applied DRAMOTE to develop robust models for predicting FDA approved drugs that have high probability to interact with the thyroid stimulating hormone receptor (TSHR) in humans. Our findings are further partially and indirectly supported by 3D docking results and literature information. The results based on approximately 500,000 interactions suggest that DRAMOTE has performed the best and that it can be used for developing robust virtual screening models. The datasets and implementation of all solutions are available as a MATLAB toolbox online at www.cbrc.kaust.edu.sa/dramote and can be found on Figshare.

  4. Mining Chemical Activity Status from High-Throughput Screening Assays

    KAUST Repository

    Soufan, Othman; Ba Alawi, Wail; Afeef, Moataz A.; Essack, Magbubah; Rodionov, Valentin; Kalnis, Panos; Bajic, Vladimir B.

    2015-01-01

    High-throughput screening (HTS) experiments provide a valuable resource that reports biological activity of numerous chemical compounds relative to their molecular targets. Building computational models that accurately predict such activity status (active vs. inactive) in specific assays is a challenging task given the large volume of data and frequently small proportion of active compounds relative to the inactive ones. We developed a method, DRAMOTE, to predict activity status of chemical compounds in HTP activity assays. For a class of HTP assays, our method achieves considerably better results than the current state-of-the-art-solutions. We achieved this by modification of a minority oversampling technique. To demonstrate that DRAMOTE is performing better than the other methods, we performed a comprehensive comparison analysis with several other methods and evaluated them on data from 11 PubChem assays through 1,350 experiments that involved approximately 500,000 interactions between chemicals and their target proteins. As an example of potential use, we applied DRAMOTE to develop robust models for predicting FDA approved drugs that have high probability to interact with the thyroid stimulating hormone receptor (TSHR) in humans. Our findings are further partially and indirectly supported by 3D docking results and literature information. The results based on approximately 500,000 interactions suggest that DRAMOTE has performed the best and that it can be used for developing robust virtual screening models. The datasets and implementation of all solutions are available as a MATLAB toolbox online at www.cbrc.kaust.edu.sa/dramote and can be found on Figshare.

  5. Chemical Composition and Antimicrobial Activity of Royal Jelly - Review

    Directory of Open Access Journals (Sweden)

    Lavinia Ioana Bărnuţiu

    2011-10-01

    Full Text Available The present paper presents the literature data regarding the chemical composition and antimicrobial activity of RoyalJelly. Royal Jelly is a secretion from the hypofaringeal glands of worker bees which serves as a food for queen beeand to the growing up larvae. Having biological properties already proven, Royal Jelly has considerable commercialappeal and is today used in many sectors (pharmaceutical, food industries and cosmetic products. Thephysicochemical composition of pure royal jelly are analyzed by determining moisture, ash, lipids, proteins,vitamins,aminoacids, carbohydrates, 10-HDA; RJ is the key substance in the antimicrobial function of the system Apismellifera. The intact Royal Jelly exhibited the highest antibacterial activity.

  6. Chemical composition and larvicidal activity of Rollinia leptopetala (Annonaceae)

    Energy Technology Data Exchange (ETDEWEB)

    Feitosa, Edinilza M.A.; Arriaga, Angela M.C.; Lemos, Telma L.G.; Oliveira, M. Conceicao F. de; Vasnconcelos, Jackson Nunes e; Lima, Jefferson Q.; Malcher, Grazielle T. [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Dept. de Quimica Organica e Inorganica]. E-mail: angelamcarriaga@yahoo.com.br; Santiago, Gilvandete M.P. [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Dept. de Farmacia; Nascimento, Ronaldo F. do [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Dept. de Quimica Analitica e Fisico-Quimica; Braz-Filho, Raimundo [Universidade Estadual do Norte Fluminense (UENF), Campos dos Goytacases, RJ (Brazil). Setor de Quimica de Produtos Naturais. Lab. de Ciencias Quimicas

    2009-07-01

    The aim of present study was to describe the chemical composition of the essential oils from the leaf and stem of Rollinia leptopetala R. E. Fries (Annonaceae) and to evaluate the larvicidal activities of these essential oils, of the methanol extract from roots of this plant and of the oxoaporphine alkaloid, liriodenine (1) against the third-instar of Aedes aegypti larvae. The methanol extract from the roots showed larvicidal activity with LC{sub 50} 64.6 {+-} 1.5 ppm. Higher activity was observed for the isolated alkaloid liriodenine (1), LC{sub 50} 3.6 {+-} 0.4 ppm. The essential oils from the leaves and stems, also exhibited larvicidal activity with LC{sub 50} 104.7 {+-} 0.2 and 34.7 {+-} 0.3 ppm, respectively. These results suggest R. leptopetala as a source of natural larvicidal compounds. This is the first report about the chemical composition and larvicidal activity of the leaf and stem essential oils of R. leptopetala. (author)

  7. Chemical composition and larvicidal activity of Rollinia leptopetala (Annonaceae)

    International Nuclear Information System (INIS)

    Feitosa, Edinilza M.A.; Arriaga, Angela M.C.; Lemos, Telma L.G.; Oliveira, M. Conceicao F. de; Vasnconcelos, Jackson Nunes e; Lima, Jefferson Q.; Malcher, Grazielle T.; Santiago, Gilvandete M.P.; Nascimento, Ronaldo F. do; Braz-Filho, Raimundo

    2009-01-01

    The aim of present study was to describe the chemical composition of the essential oils from the leaf and stem of Rollinia leptopetala R. E. Fries (Annonaceae) and to evaluate the larvicidal activities of these essential oils, of the methanol extract from roots of this plant and of the oxoaporphine alkaloid, liriodenine (1) against the third-instar of Aedes aegypti larvae. The methanol extract from the roots showed larvicidal activity with LC 50 64.6 ± 1.5 ppm. Higher activity was observed for the isolated alkaloid liriodenine (1), LC 50 3.6 ± 0.4 ppm. The essential oils from the leaves and stems, also exhibited larvicidal activity with LC 50 104.7 ± 0.2 and 34.7 ± 0.3 ppm, respectively. These results suggest R. leptopetala as a source of natural larvicidal compounds. This is the first report about the chemical composition and larvicidal activity of the leaf and stem essential oils of R. leptopetala. (author)

  8. Antimicrobial activity of Iranian propolis and its chemical composition

    Directory of Open Access Journals (Sweden)

    Yaghoubi M.J.

    2007-04-01

    Full Text Available The objective of this study was to investigate the antimicrobial activity of ethanol extract of Iranian propolis on some microorganisms using disc diffusion method. The chemical composition of the propolis was also investigated using thin layer chromatography and spectrophotometric methods. Ethanol extract of propolis showed activity only against Gram-positives and fungi, whereas no activity was observed against Gram-negatives. Thin layer chromatography screening revealed the presence of pinocembrine, caffeic acid, kaempferol, phenethyl caffeate, chrysin, and galangin in Iranian propolis. The total flavonoid and phenolic contents were 7.3% and 36%, respectively, which suggests that the strong antimicrobial activity of Iranian propolis may be due to high levels of phenolic and flavonoid compounds.

  9. Pair Interaction of Catalytical Sphere Dimers in Chemically Active Media

    Directory of Open Access Journals (Sweden)

    Jing-Min Shi

    2018-01-01

    Full Text Available We study the pair dynamics of two self-propelled sphere dimers in the chemically active medium in which a cubic autocatalytic chemical reaction takes place. Concentration gradient around the dimer, created by reactions occurring on the catalytic sphere surface and responsible for the self-propulsion, is greatly influenced by the chemical activities of the environment. Consequently, the pair dynamics of two dimers mediated by the concentration field are affected. In the particle-based mesoscopic simulation, we combine molecular dynamics (MD for potential interactions and reactive multiparticle collision dynamics (RMPC for solvent flow and bulk reactions. Our results indicate three different configurations between a pair of dimers after the collision, i.e., two possible scenarios of bound dimer pairs and one unbound dimer pair. A phase diagram is sketched as a function of the rate coefficients of the environment reactions. Since the pair interactions are the basic elements of larger scale systems, we believe the results may shed light on the understanding of the collective dynamics.

  10. Nonlinear processes in laser heating of chemically active media

    Energy Technology Data Exchange (ETDEWEB)

    Bunkin, F V; Kirichenko, N A; Luk' yanchuk, B S

    1984-08-01

    After it had been discovered and in due measure physically comprehended that numerous nontrivial phenomena observed during laser heating of chemically active media are caused primarily by self-stress of laser radiation due to the chemical intertial nonlinearity of the medium, an approach was found for solving problems of laser thermochemistry that is most adequate from the mathematical (and physical) standpoint: the approach of the theory of nonlinear oscillations in point systems and distributed systems. This approach has provided a uniform viewpoint for examination of a variety of phenomena of spatiotemporal self-organization of chemically active media under the effect of laser radiation, qualitative, and in some cases quantitative description of such phenomena as the onset of thermochemical instability, self-oscillations, various spatial structures and the like. Evidently it can be rightly considered that at this juncture a definite stage has been completed in the development of laser thermochemistry marked by the creation of an ideology, method and overall approach to interpretation of the most diverse phenomena under conditions of actual physical experiments. References to the numerous studies that make up the content of this stage of development of laser thermochemistry are to be found in survey papers. 48 references, 10 figures.

  11. Active hydrothermal and non-active massive sulfide mound investigation using a new multiparameter chemical sensor

    Science.gov (United States)

    Han, C.; Wu, G.; Qin, H.; Wang, Z.

    2012-12-01

    Investigation of active hydrothermal mound as well as non-active massive sulfide mound are studied recently. However, there is still lack of in-situ detection method for the non-active massive sulfide mound. Even though Transient ElectroMagnetic (TEM) and Electric Self-potential (SP) methods are good, they both are labour, time and money cost work. We proposed a new multiparameter chemical sensor method to study the seafloor active hydrothermal mound as well as non-active massive sulfide mound. This sensor integrates Eh, S2- ions concentration and pH electrochemical electrodes together, and could found chemical change caused by the active hydrothermal vent, even weak chemical abnormalities by non-active massive sulfide hydrothermal mound which MARP and CTD sometimes cannot detect. In 2012, the 1st Leg of the Chinese 26th cruise, the multiparameter chemical sensor was carried out with the deepsea camera system over the Carlsberg Ridge in Indian Ocean by R/V DAYANGYIHAO. It was shown small Eh and S2- ions concentration abnormal around a site at Northwest Indian ridge. This site was also evidenced by the TV grab. In the 2nd Leg of the same cruise in June, this chemical sensor was carried out with TEM and SP survey system. The chemical abnormalities are matched very well with both TEM and SP survey results. The results show that the multiparameter chemical sensor method not only can detect active hydrothermal mound, but also can find the non-active massive sulfide hydrothermal mound.

  12. Active multispectral reflection fingerprinting of persistent chemical agents

    Science.gov (United States)

    Tholl, H. D.; Münzhuber, F.; Kunz, J.; Raab, M.; Rattunde, M.; Hugger, S.; Gutty, F.; Grisard, A.; Larat, C.; Papillon, D.; Schwarz, M.; Lallier, E.; Kastek, M.; Piatkowski, T.; Brygo, F.; Awanzino, C.; Wilsenack, F.; Lorenzen, A.

    2017-10-01

    Remote detection of toxic chemicals of very low vapour pressure deposited on surfaces in form of liquid films, droplets or powder is a capability that is needed to protect operators and equipment in chemical warfare scenarios and in industrial environments. Infrared spectroscopy is a suitable means to support this requirement. Available instruments based on passive emission spectroscopy have difficulties in discriminating the infrared emission spectrum of the surface background from that of the contamination. Separation of background and contamination is eased by illuminating the surface with a spectrally tune-able light source and by analyzing the reflectivity spectrum. The project AMURFOCAL (Active Multispectral Reflection Fingerprinting of Persistent Chemical Agents) has the research topic of stand-off detection and identification of chemical warfare agents (CWAs) with amplified quantum cascade laser technology in the long-wave infrared spectral range. The project was conducted under the Joint Investment Programme (JIP) on CBRN protection funded through the European Defence Agency (EDA). The AMURFOCAL instrument comprises a spectrally narrow tune-able light source with a broadband infrared detector and chemometric data analysis software. The light source combines an external cavity quantum cascade laser (EC-QCL) with an optical parametric amplifier (OPA) to boost the peak output power of a short laser pulse tune-able over the infrared fingerprint region. The laser beam is focused onto a target at a distance between 10 and 20 m. A 3D data cube is registered by tuning the wavelength of the laser emission while recording the received signal scattered off the target using a multi-element infrared detector. A particular chemical is identified through the extraction of its characteristic spectral fingerprint out of the measured data. The paper describes the AMURFOCAL instrument, its functional units, and its principles of operation.

  13. Simaroubaceae family: botany, chemical composition and biological activities

    Directory of Open Access Journals (Sweden)

    Iasmine A.B.S. Alves

    Full Text Available The Simaroubaceae family includes 32 genera and more than 170 species of trees and brushes of pantropical distribution. The main distribution hot spots are located at tropical areas of America, extending to Africa, Madagascar and regions of Australia bathed by the Pacific. This family is characterized by the presence of quassinoids, secondary metabolites responsible of a wide spectrum of biological activities such as antitumor, antimalarial, antiviral, insecticide, feeding deterrent, amebicide, antiparasitic and herbicidal. Although the chemical and pharmacological potential of Simaroubaceae family as well as its participation in official compendia; such as British, German, French and Brazilian pharmacopoeias, and patent registration, many of its species have not been studied yet. In order to direct further investigation to approach detailed botanical, chemical and pharmacological aspects of the Simaroubaceae, the present work reviews the information regarding the main genera of the family up to 2013.

  14. Antibacterial activity of chemical constituents isolated from Asparagus racemosus

    Directory of Open Access Journals (Sweden)

    Muhammad Abdullah Shah

    2014-03-01

    Full Text Available Asparagus racemosus is a medical extensively used in traditional medicine for various disorders including its use in infectious. So far work has been done to identify its active constituents responsible for antiseptic folk use of this plant. In the current investigation, we have made an effort to identify its chemical constituents that might be partly responsible for antimicrobial properties. Extraction and isolation of plant extract lead to isolation of two nor-lignans and two steroidal triterpenes (compound 1 to 4. All compound showed considerable antibacterial activities against E. coli and S. aureus while no significant activity was observed against S. typhi. This study highlighted the potential of A. racemosus to be further explored as a source of bioactive natural products.

  15. Pereskia aculeata Muller (Cactaceae Leaves: Chemical Composition and Biological Activities

    Directory of Open Access Journals (Sweden)

    Lucèia Fàtima Souza

    2016-09-01

    Full Text Available The aims of this work were to study the chemical composition of the essential oil from the leaves of Pereskia aculeata and to evaluate some biological activities of three leaf extracts. The phenolic content, antioxidant activity, and in vitro antimicrobial and antifungal activities were determined. The methanol extract showed antioxidant activity (EC50 7.09 mg/mL and high polyphenols content (15.04 ± 0.31 mg gallic acid equivalents (GAE/g. The petroleum ether extract exhibited potent antibacterial activity against Escherichia coli, whereas the chloroform extract showed inhibitory activity against Bacillus cereus and Staphylococcus aureus. The petroleum ether and methanol extracts were more effective in inhibiting the growth of Aspergillus versicolor. The possible cytotoxicity of extracts on neuroblastoma SH-SY5Y cancer cell line and the influence on adenylate cyclase (ADCY expression was also studied. P. aculeata chloroform extract showed antiproliferative activity with an IC50 value of 262.83 µg/mL. Treatments of SH-SY5Y neuroblastoma cells with 100 µg/mL of methanol extract significantly reduced ADCY1 expression.

  16. Pereskia aculeata Muller (Cactaceae) Leaves: Chemical Composition and Biological Activities.

    Science.gov (United States)

    Souza, Lucèia Fàtima; Caputo, Lucia; Inchausti De Barros, Ingrid Bergman; Fratianni, Florinda; Nazzaro, Filomena; De Feo, Vincenzo

    2016-09-03

    The aims of this work were to study the chemical composition of the essential oil from the leaves of Pereskia aculeata and to evaluate some biological activities of three leaf extracts. The phenolic content, antioxidant activity, and in vitro antimicrobial and antifungal activities were determined. The methanol extract showed antioxidant activity (EC50 7.09 mg/mL) and high polyphenols content (15.04 ± 0.31 mg gallic acid equivalents (GAE)/g). The petroleum ether extract exhibited potent antibacterial activity against Escherichia coli, whereas the chloroform extract showed inhibitory activity against Bacillus cereus and Staphylococcus aureus. The petroleum ether and methanol extracts were more effective in inhibiting the growth of Aspergillus versicolor. The possible cytotoxicity of extracts on neuroblastoma SH-SY5Y cancer cell line and the influence on adenylate cyclase (ADCY) expression was also studied. P. aculeata chloroform extract showed antiproliferative activity with an IC50 value of 262.83 µg/mL. Treatments of SH-SY5Y neuroblastoma cells with 100 µg/mL of methanol extract significantly reduced ADCY1 expression.

  17. Thermo-Chemical Conversion of Microwave Activated Biomass Mixtures

    Science.gov (United States)

    Barmina, I.; Kolmickovs, A.; Valdmanis, R.; Vostrikovs, S.; Zake, M.

    2018-05-01

    Thermo-chemical conversion of microwave activated wheat straw mixtures with wood or peat pellets is studied experimentally with the aim to provide more effective application of wheat straw for heat energy production. Microwave pre-processing of straw pellets is used to provide a partial decomposition of the main constituents of straw and to activate the thermo-chemical conversion of wheat straw mixtures with wood or peat pellets. The experimental study includes complex measurements of the elemental composition of biomass pellets (wheat straw, wood, peat), DTG analysis of their thermal degradation, FTIR analysis of the composition of combustible volatiles entering the combustor, the flame temperature, the heat output of the device and composition of the products by comparing these characteristics for mixtures with unprocessed and mw pre-treated straw pellets. The results of experimental study confirm that mw pre-processing of straw activates the thermal decomposition of mixtures providing enhanced formation of combustible volatiles. This leads to improvement of the combustion conditions in the flame reaction zone, completing thus the combustion of volatiles, increasing the flame temperature, the heat output from the device, the produced heat energy per mass of burned mixture and decreasing at the same time the mass fraction of unburned volatiles in the products.

  18. Chemically activated nanodiamonds for aluminum alloy corrosion protection and monitoring

    Science.gov (United States)

    Hannstein, Inga; Adler, Anne-Katrin; Lapina, Victoria; Osipov, Vladimir; Opitz, Jörg; Schreiber, Jürgen; Meyendorf, Norbert

    2009-03-01

    In the present study, a smart coating for light metal alloys was developed and investigated. Chemically activated nanodiamonds (CANDiT) were electrophoretically deposited onto anodized aluminum alloy AA2024 substrates in order to increase corrosion resistance, enhance bonding properties and establish a means of corrosion monitoring based on the fluorescence behavior of the particles. In order to create stable aqueous CANDiT dispersions suitable for electrophoretic deposition, mechanical milling had to be implemented under specific chemical conditions. The influence of the CANDiT volume fraction and pH of the dispersion on the electrochemical properties of the coated samples was investigated. Linear voltammetry measurements reveal that the chemical characteristics of the CANDiT dispersion have a distinct influence on the quality of the coating. The fluorescence spectra as well as fluorescence excitation spectra of the samples show that corrosion can be easily detected by optical means. Furthermore, an optimization on the basis of "smart" - algorithms for the data processing of a surface analysis by the laser-speckle-method is presented.

  19. Chemical constituents and biological activities of Dianthus elegans var. elegans.

    Science.gov (United States)

    Mutlu, Kiymet; Sarikahya, Nazli Boke; Nalbantsoy, Ayse; Kirmizigul, Suheyla

    2018-06-01

    Chemical investigation of the aerial parts of Dianthus elegans var. elegans afforded two previously undescribed saponins, named dianosides M-N (1-2), together with four oleanane-type triterpenoid glycosides (3-6). Their structures were elucidated as 3-O-α-L-arabinofuranosyl-16α-hydroxyolean-12-ene-23α, 28β-dioic acid (1) and 3-O-α-L-arabinofuranosyl-(1 → 3)-β-D-glucopyranosyl 16α-hydroxyolean-12-ene-23α-oic acid, 28-O-β-D-glucopyranosyl-(1 → 6)-β-D-glycosyl ester (2) by chemical and extensive spectroscopic methods including IR, 1D, 2D NMR and HRESIMS. Both of the saponins were evaluated for their cytotoxicities against HEK-293, A-549 and HeLa human cancer cells using the MTT method. All compounds showed no substantial cytotoxic activity against tested cell lines. However, dianosides M-N and the n-butanol fraction exhibited considerable haemolysis in human erythrocyte cells. The immunomodulatory properties of dianosides M-N were also evaluated in activated whole blood cells by PMA plus ionomycin. Dianosides M-N increased IL-1β concentration significantly whereas the n-butanol fraction slightly augmented IL-1β secretion. All compounds did not change IL-2 and IFN-γ levels considerably.

  20. Chemical composition and antioxidant activity of two strawberry cultivars

    Directory of Open Access Journals (Sweden)

    Đilas Sonja M.

    2011-01-01

    Full Text Available The macro- and micro-chemical composition, as well as antioxidant activity of two strawberry cultivars, Marmolada and Clery, were studied. Results showed a noticeable difference in the sugar, protein and pectin contents. Clery had 6.92% and Marmolada 4.93% of total sugar. Also, protein and pectin contents were higher in the Clery cultivar. No significant difference was observed in acidity, as well as in ash and cellulose content. Marmolada had a higher content of total phenolics and flavonoids (228.04 mg GAE /100 g FW and 136.01 mg RE/100 g FW, respectively . The anthocyanins content in Marmolada (32.0 mg CGE/100 g FW was slightly lower than in Clery (36.0 mg CGE/100 g FW. The antioxidant activity was evaluated spectrophotometrically, using 2,2-diphenyl- 1-picrylhydrazyl (DPPH radical scavenging activity assay. The DPPH free radical scavenging activity, expressed as EC50 value, of Marmolada (0.77 mg/ml was higher than of Clery (0.83 mg/ml. There was a significant positive correlation (R2>0.90 between the concentration of phenolics/flavonoids/anthocyanins and DPPH radical scavenging activity of both strawberry cultivars. These results also showed that the antioxidant value of 100 g FW Marmolada and Clery is equivalent to 237.91 mg and 219.01 mg of vitamin C, respectively.

  1. Antimicrobial, antioxidant activities and chemical composition of selected Thai spices

    Directory of Open Access Journals (Sweden)

    Juraithip Wungsintaweekul

    2010-12-01

    Full Text Available Nine volatile oils and six methanol extracts from Ocimum americanum, O. basilicum, O. sanctum, Citrus hystrix,Alpinia galanga, Curcuma zedoaria, Kaempferia parviflora and Zingiber cassumunar were assessed for antimicrobial andantioxidant activities. The volatile oils and extracts were investigated against eight bacteria and three fungi. The resultsillustrated that O. americanum volatile oil exhibited broad spectrum activity against tested bacteria with the MICs ranging1.4-3.6 mg/ml and Candida spp. with the MICs ranging from 0.5-0.6 mg/ml. The O. sanctum volatile oil showed a considerableactivity against only Candida spp. with the MICs ranging from 0.8-1.4 mg/ml. Interestingly, growth of Mycobacteriumphlei was inhibited by the volatiles of O. americanum, C. hystrix peel, and C. zedoaria with MIC of 1.7, 3.5 and 1.2 mg/ml,respectively. For antioxidant activity evaluation, the methanol extracts of C. hystrix (leaf and peel and K. parviflora hadpotent antioxidant activity by the radical-scavenging DPPH method with IC50 of 24.6, 66.3 and 61.5 mg/ml, respectively.GC-MS analysis revealed the typical chemical profiles of the volatile oils. The major component showed the characteristicsof the volatile oils and was probably responsible for the antimicrobial effect.

  2. Chemical compositions and antioxidant activity of Heracleum persicum essential oil

    Directory of Open Access Journals (Sweden)

    Maryam Gharachorloo

    2018-02-01

    Full Text Available ABSTRACT In this study essential oil of the aerial parts of Heracleum persicum a spice widely used in Iran was isolated by conventional hydrodistillation (HD and microwave-assisted hydrodistillation (MAHD techniques. The extraction yield was determined and the chemical compositions of essential oils were identified by the application of gas chromatography/mass spectrometry (GC/MS. The antioxidant activity was determined by two different methods: 1,1-diphenyl-2-picrylhydrazyl (DPPH free radical scavenging and oven test methods. Although the main compounds of essential oils by the both extraction methods were similar, the essential oil extracted by HD with lower extraction efficiency showed more diverse compounds. The evaluation of antioxidant activity of the essential oil measured by delay in sunflower oil oxidation indicated that the antioxidant activity was dependent on the concentration which increased when higher concentrations of the essential oils were applied. The results of DPPH radical assay also indicated that the percentage of inhibition increased with increasing of essential oil concentration and IC50 value for essential oil extracted by MAHD method was obtained 1.25 mg/mL. Therefore the Heracleum persicum essential oil might be recommended for use as a flavoring agent and a source of natural antioxidants in functional foods, formulation of the supplements and in medicinal due to numerous pharmacological activities.

  3. Wound Healing Activity and Chemical Standardization of Eugenia pruniformis Cambess

    Science.gov (United States)

    de Albuquerque, Ricardo Diego Duarte Galhardo; Perini, Jamila Alessandra; Machado, Daniel Escorsim; Angeli-Gamba, Thaís; Esteves, Ricardo dos Santos; Santos, Marcelo Guerra; Oliveira, Adriana Passos; Rocha, Leandro

    2016-01-01

    Background: Eugenia pruniformis is an endemic species from Brazil. Eugenia genus has flavonoids as one of the remarkable chemical classes which are related to the improvement of the healing process. Aims: To evaluate of wound healing activity of E. pruniformis leaves and to identify and quantify its main flavonoids compounds. Materials And Methods: Wound excision model in rats was used to verify the hydroethanolic and ethyl acetate extracts potential. The animals were divided in four groups of six and the samples were evaluated until the 15° day of treatment. Hydroxyproline dosage and histological staining with hematoxilin-eosin and Sirius Red were used to observe the tissue organization and quantify the collagen deposition, respectively. Chemical compounds of the ethyl acetate extract were identified by chromatographic techniques and mass spectrometry analysis and total flavonoids content was determined by spectrophotometric method. The antioxidant activity was determined by oxygen radical absorbing capacity (ORAC) and 2,2-diphenyl-1-picrylhydrazylhydrate radical photometric (DPPH) assays. Results: The treated group with the ethyl acetate extract showed collagen deposition increase, higher levels of hidroxyproline, better tissue reorganization and complete remodeling of epidermis. Quercetin, kaempferol and hyperoside were identified as main compounds and flavonoids content value was 43% (w/w). The ORAC value of the ethyl acetate extract was 0.81± 0.05 mmol TE/g whereas the concentration to produce 50% reduction of the DPPH was 7.05± 0.09 μg/mL. Conclusion: The data indicate a wound healing and antioxidant activities of E. pruniformis. This study is the first report of flavonoids and wound healing activity of E. pruniformis. KEY MESSAGES Eugenia pruniformis extract accelerates wound healing in skin rat model, probably due to its involvement with the collagen deposition increase, higher levels of hidroxyproline, dermal remodelling and potent antioxidant activity

  4. Cosmetics chemical composition characterization by instrumental neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Alves, Ana Paula; Pereira, Gustavo Jose; Amaral, Angela Maria; Ferreira, Andrea Vidal, E-mail: ana_allves2008@hotmail.co [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2009-07-01

    Brazil is in the third position in the world's cosmetics market. It is an expanding and growing market where new products and manufacturing processes are in a constant and steady expansion. Therefore, it is mandatory that the composition of the products is well known in order to guarantee safety and quality of daily used cosmetics. The Brazilian National Health Surveillance Agency (ANVISA) has issued a resolution, RDC No. 48, March 16, 2006, which defines a 'List of Substances which can not be used in personal hygiene products, cosmetics and perfumes'. In this work, samples of locally manufactured and imported cosmetics (lipsticks, eye shadows, etc.) were analyzed using the Instrumental Neutron Activation Analysis technique. The samples were irradiated in the TRIGA IPR-R1 reactor of the Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN), on a 100kW thermal power, with a thermal neutron fluence rate about 8x10{sup 11}ncm{sup -2}s{sup -1}. The analysis has detected the chemical elements Br, Ba, Ga, Na, K, Sc, Fe, Cr, Zn, Sm, W, La, Rb, Cs, Ta, Ge, Co, U, Ti, V, Cl, Al, Mn and Cu. The concentrations of these elements are on a range from 5 to 3000mug.g{sup -1}. Some chemical elements observed in samples (Cl, Br, Cr, U) are included at ANVISA prohibitive list. (author)

  5. Cosmetics chemical composition characterization by instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    Alves, Ana Paula; Pereira, Gustavo Jose; Amaral, Angela Maria; Ferreira, Andrea Vidal

    2009-01-01

    Brazil is in the third position in the world's cosmetics market. It is an expanding and growing market where new products and manufacturing processes are in a constant and steady expansion. Therefore, it is mandatory that the composition of the products is well known in order to guarantee safety and quality of daily used cosmetics. The Brazilian National Health Surveillance Agency (ANVISA) has issued a resolution, RDC No. 48, March 16, 2006, which defines a 'List of Substances which can not be used in personal hygiene products, cosmetics and perfumes'. In this work, samples of locally manufactured and imported cosmetics (lipsticks, eye shadows, etc.) were analyzed using the Instrumental Neutron Activation Analysis technique. The samples were irradiated in the TRIGA IPR-R1 reactor of the Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN), on a 100kW thermal power, with a thermal neutron fluence rate about 8x10 11 ncm -2 s -1 . The analysis has detected the chemical elements Br, Ba, Ga, Na, K, Sc, Fe, Cr, Zn, Sm, W, La, Rb, Cs, Ta, Ge, Co, U, Ti, V, Cl, Al, Mn and Cu. The concentrations of these elements are on a range from 5 to 3000μg.g -1 . Some chemical elements observed in samples (Cl, Br, Cr, U) are included at ANVISA prohibitive list. (author)

  6. Chemical constituents and biological activities of the genus Linaria (Scrophulariaceae).

    Science.gov (United States)

    Cheriet, Thamere; Mancini, Ines; Seghiri, Ramdane; Benayache, Fadila; Benayache, Samir

    2015-01-01

    This is a review on 95 references dealing with the genus Linaria (Scrophularioideae-Antirrhineae tribe), a known genus of the Scrophulariaceae family, which comprises about 200 species mainly distributed in Europe, Asia and North Africa. The use of some Linaria species in folk medicine has attracted the attention for chemical and biological studies. This report is aimed to be a comprehensive overview on the isolated or identified known and often new metabolites from the 41 Linaria species so far cited. It is organised presenting first the phytochemical classes of alkaloids, polyphenols including flavonoids, the latter being quite diffused and mostly present as flavones, flavonols and their glycosides, and terpenoids including iridoids and steroids. Second, the results from biological investigation on plant extracts, pure natural products isolated from Linaria species and some synthetic derivatives are reported, with antitumour, anti-acetylcholinesterase, anti-inflammatory and analgesic, antioxidant and antibacterial activities.

  7. Safety- and Risk Analysis Activities in Chemical Industry in Europe

    International Nuclear Information System (INIS)

    Kozine, Igor; Duijm, Nijs Jan; Lauridsen Kurt

    2001-01-01

    European and International mechanism of handling safety- and risk-related matters. So, the Organisation for Economic Co-operation and Development's (OECD) core objective on risk management is to support Member countries' efforts to develop national policies and actions, and, where appropriate, to develop and implement international risk management measures. In support of this objective, the OECD Risk Management Programme focuses on two areas: (1) developing methods and technical tools that can be used by OECD and Member countries to enhance their current risk management programmes; and (2) identifying specific chemical exposures of concern in Member countries and evaluating possible risk management opportunities. The current paper highlights the EU legislation on major accident hazards related to the chemical industry, differences in the national approaches to risk analyses in the process industry and European-scale activity in improving the understanding of the sources of uncertainty in risk assessments

  8. Flaxseed hull: Chemical composition and antioxidant activity during development.

    Science.gov (United States)

    Herchi, Wahid; Al Hujaili, Abdullah D; Sakouhi, Faouzi; Sebei, Khaled; Trabelsi, Hajer; Kallel, Habib; Boukhchina, Sadok

    2014-01-01

    Changes in the chemical composition and antioxidant activity of flaxseed hull during maturation were investigated. P129 hull variety was studied at four maturation stages (St1, St2, St3, and St4). Significant variation in proximate composition and flaxseed hull oil characteristics were observed. A significant increase in the carbohydrates content of the hull was observed during development. The main methyl esters were linolenic acid (48.95 - 51.52 %), oleic acid (20.27-23.41%) and linoleic acid (15.62-17.70%). The highest polyunsaturated fatty acids (PUFA) were found to be 67.14 % at the first stage of maturity (St1). Flaxseed hull oil was of good quality, containing an abundance of omega-3 essential fatty acids. The iodine value increased, while the saponification value of oil decreased during seed development. The decrease in ascorbic acid content was steady. The maximum level of total phenolic acid content (128.3 mg/100 g oil) was reached at 7 DAF. The antioxidant activity of oilseed was assessed by means of 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging assay. Radical scavenging activity for green hull was 52.74% and mature hull was 69.32%.

  9. Pinus Roxburghii essential oil anticancer activity and chemical composition evaluation.

    Science.gov (United States)

    Sajid, Arfaa; Manzoor, Qaisar; Iqbal, Munawar; Tyagi, Amit Kumar; Sarfraz, Raja Adil; Sajid, Anam

    2018-01-01

    The present study was conducted to appraise the anticancer activity of Pinus roxburghii essential oil along with chemical composition evaluation. MTT assay revealed cytotoxicity induction in colon, leukemia, multiple myeloma, pancreatic, head and neck and lung cancer cells exposed to essential oil. Cancer cell death was also observed through live/dead cell viability assay and FACS analysis. Apoptosis induced by essential oil was confirmed by cleavage of PARP and caspase-3 that suppressed the colony-forming ability of tumor cells and 50 % inhibition occurred at a dose of 25 μg/mL. Moreover, essential oil inhibited the activation of inflammatory transcription factor NF-κB and inhibited expression of NF-κB regulated gene products linked to cell survival (survivin, c-FLIP, Bcl-2, Bcl-xL, c-Myc, c-IAP2), proliferation (Cyclin D1) and metastasis (MMP-9). P. roxburghii essential oil has considerable anticancer activity and could be used as anticancer agent, which needs further investigation to identify and purify the bioactive compounds followed by in vivo studies.

  10. Active sampling technique to enhance chemical signature of buried explosives

    Science.gov (United States)

    Lovell, John S.; French, Patrick D.

    2004-09-01

    Deminers and dismounted countermine engineers commonly use metal detectors, ground penetrating radar and probes to locate mines. Many modern landmines have a very low metal content, which severely limits the effectiveness of metal detectors. Canines have also been used for landmine detection for decades. Experiments have shown that canines smell the explosives which are known to leak from most types of landmines. The fact that dogs can detect landmines indicates that vapor sensing is a viable approach to landmine detection. Several groups are currently developing systems to detect landmines by "sniffing" for the ultra-trace explosive vapors above the soil. The amount of material that is available to passive vapor sensing systems is limited to no more than the vapor in equilibrium with the explosive related chemicals (ERCs) distributed in the surface soils over and near the landmine. The low equilibrium vapor pressure of TNT in the soil/atmosphere boundary layer and the limited volume of the boundary layer air imply that passive chemical vapor sensing systems require sensitivities in the picogram range, or lower. ADA is working to overcome many of the limitations of passive sampling methods, by the use of an active sampling method that employs a high-powered (1,200+ joules) strobe lamp to create a highly amplified plume of vapor and/or ERC-bearing fine particulates. Initial investigations have demonstrated that this approach can amplify the detectability of TNT by two or three orders of magnitude. This new active sampling technique could be used with any suitable explosive sensor.

  11. Chemical composition and antioxidant activity of berry fruits

    Directory of Open Access Journals (Sweden)

    Stajčić Slađana M.

    2012-01-01

    Full Text Available The main chemical composition, contents of total phenolic (TPh, total flavonoid (TF, and total monomeric anthocyianin (TMA, as well as the antioxidant activity of two raspberry cultivars (Meeker and Willamette, two blackberry cultivars (Čačanska bestrna and Thornfree and wild bilberry were studied. The raspberry cultivars had the highest total solids among fruits investigated. Bilberry fruits had the highest sugar-to-acid ratio. Blackberry fruits were richer in crude fibers (cellulose in comparison to raspberry and bilberry fruits. The content of pectic substances was highest in the bilberry. Also, bilberry had a highest content of TPh (808.12 mg GAE/100 g FW, TF (716.31 mg RE/100 g FW and TMA (447.83 mg CGE/100 g FW. The antioxidant activity was evaluated spectrophotometrically, using 2,2-diphenyl-1-picrylhydrazyl (DPPH radical scavenging activity assay. The DPPH free radical scavenging activity, expressed as the EC50 value (in mg of fresh weight of berry fruit per ml of the reaction mixture, of bilberry (0.3157 ± 0.0145 mg/ml was the highest. These results also showed that the antioxidant value of 100 g FW bilberry, raspberry - Willamette, raspberry - Meeker, blackberry - Čačanska bestrna and blackberry - Thornfree is equivalent to 576.50 mg, 282.74 mg, 191.58 mg, 222.28 mg and 272.01 mg of vitamin C, respectively. There was a significant positive correlation between the antioxidant activities and content of total phenolics (RTPh 2=0.9627, flavonoids (RTF 2=0.9598 and anthocyanins (RTMA 2=0.9496 in berry fruits. [Projekat Ministarstva nauke Republike Srbije, br. TR 31044

  12. Chemical Composition and Antimicrobial Activities of Iranian Propolis

    Science.gov (United States)

    Afrouzan, Houshang; Tahghighi, Azar; Zakeri, Sedigheh; Es-haghi, Ali

    2018-01-01

    Background: With considering the importance of natural products for their remedial and therapeutic value, this research was aimed to analyze the chemical compositions and antimicrobial activity of four propolis samples from different areas of Iran (Chenaran, Taleghan, Morad Beyg, and Kalaleh) with various climates and flora. Methods: Ethanolic (70% EtOH) and dichlromethane (DCM) extracts of Iranian propolis were analyzed by gas chromatography-mass spectrometry (GC-MS) methods, and antimicrobial activity was evaluated against Candida albicans, Escherichia coli, and Staphylococcus aureus using disk diffusion antimicrobial method. Results: The results of GC-MS analysis showed the presence of fatty acids, flavonoids, terpenes, aromatic-aliphatic acids, and their related esters. The total flavonoids in DCM extract of Chenaran, Taleghan, Morad Beyg, and Kalaleh propolis were pinocembrin and pinostrobin chalcone. The common phenolic and terpene compounds detected in all four tested EtOH extracts were P-cumaric acid and dimethyl -1,3,5,6-tetramethyl-[1,3-(13C2)] bicycloce [5.5.0] dodeca-1,3,5,6,8,10-hexaene-9,10-dicarboxylate, respectively. The highest inhibitory diameter zone of the Iranian propolis against C. albicans, E. coli, and S. aureus was for DCM extract of Kalaleh propolis (13.33 mm), Morad Beyg propolis (12 mm), and Kalaleh (11.67 mm), respectively. Conclusion: Iranian propolis showed antimicrobial activities against C. albicans, E. coli, and S. aurous, perhaps due to the presence of flavonoids, phenolic acids, and terpenes as active components that can be used alone or in combination with the selected antibiotics to synergize antibiotic effect, as well as to prevent microbial resistance to available antimicrobial drugs. PMID:28558440

  13. Chemically induced and light-independent cryptochrome photoreceptor activation.

    Science.gov (United States)

    Rosenfeldt, Gesa; Viana, Rafael Muñoz; Mootz, Henning D; von Arnim, Albrecht G; Batschauer, Alfred

    2008-01-01

    The cryptochrome photoreceptors of higher plants are dimeric proteins. Their N-terminal photosensory domain mediates dimerization, and the unique C-terminal extension (CCT) mediates signaling. We made use of the human FK506-binding protein (FKBP) that binds with high affinity to rapamycin or rapamycin analogs (rapalogs). The FKBP-rapamycin complex is recognized by another protein, FRB, thus allowing rapamycin-induced dimerization of two target proteins. Here we demonstrate by bioluminescence resonance energy transfer (BRET) assays the applicability of this regulated dimerization system to plants. Furthermore, we show that fusion proteins consisting of the C-terminal domain of Arabidopsis cryptochrome 2 fused to FKBP and FRB and coexpressed in Arabidopsis cells specifically induce the expression of cryptochrome-controlled reporter and endogenous genes in darkness upon incubation with the rapalog. These results demonstrate that the activation of cryptochrome signal transduction can be chemically induced in a dose-dependent fashion and uncoupled from the light signal, and provide the groundwork for gain-of-function experiments to study specifically the role of photoreceptors in darkness or in signaling cross-talk even under light conditions that activate members of all photoreceptor families.

  14. Removal of toxic chemicals from water with activated carbon

    Science.gov (United States)

    Dawson, V.K.; Marking, L.L.; Bills, T.D.

    1976-01-01

    Activated carbon was effective in removing fish toxicants and anesthetics from water solutions. Its capacity to adsorb 3-trifluoromethyl-4-nitrophenol (TFM), antimycin, NoxfishA? (5% rotenone), Dibrorms, juglone, MSa??222, and benzocaine ranged from 0.1 to 64 mg per gram of carbon. The adsorptive capacity (end point considered as a significant discharge) of activated carbon for removal of TFM was determined at column depths of 15, 30, and 60 cm; temperatures of 7, 12, 17, and 22 C; pH's of 6.5, 7.5, 8.5, and 9.5; and flow rates of 50, 78, 100, 200, and 940 ml/min. Adsorptive capacity increased when the contact time was increased by reducing the flow rate or increasing the column depth. The adsorptive capacity was not significantly influenced by temperature but was substantially higher at pH 6.5 than at the other pH's tested. A practical and efficient filter for purifying chemically treated water was developed.

  15. Chemical Composition, Antifungal and Insecticidal Activities of Hedychium Essential Oils

    Directory of Open Access Journals (Sweden)

    Kanniah Rajasekaran

    2013-04-01

    Full Text Available The antimicrobial properties of essential oils have been documented, and their use as “biocides” is gaining popularity. The aims of this study were to analyze the chemical composition and assess the biological activities of Hedychium essential oils. Oils from 19 Hedychium species and cultivars were analyzed by gas chromatography (GC and gas chromatography-mass spectrometry (GC-MS techniques. The antifungal and insecticidal activities of these oils were tested against Colletotrichum acutatum, C. fragariae, and C. gloeosporioides, and three insects, the azalea lace bug (Stephanitis pyrioides, the yellow fever mosquito (Aedes aegypti, and the red imported fire ant (Solenopsis invicta. Hedychium oils were rich in monoterpenes and sesquiterpenes, especially 1,8-cineole (0.1%–42%, linalool (<0.1%–56%, a-pinene (3%–17%, b-pinene (4%–31%, and (E-nerolidol (0.1%–20%. Hedychium oils had no antifungal effect on C. gloeosporioides, C. fragariae, and C. acutatum, but most Hedychium oils effectively killed azalea lace bugs. The oils also show promise as an adult mosquito repellent, but they would make rather poor larvicides or adulticides for mosquito control. Hedychium oils acted either as a fire ant repellent or attractant, depending on plant genotype and oil concentration.

  16. Salacia crassifolia (Celastraceae: CHEMICAL CONSTITUENTS AND ANTIMICROBIAL ACTIVITY

    Directory of Open Access Journals (Sweden)

    Vanessa G. Rodrigues

    2015-02-01

    Full Text Available The phytochemical study of hexane extract from leaves of Salacia crassifolia resulted in the isolation of 3β-palmitoxy-urs-12-ene, 3-oxofriedelane, 3β-hydroxyfriedelane, 3-oxo-28-hydroxyfriedelane, 3-oxo-29-hydroxyfriedelane, 28,29-dihydroxyfriedelan-3-one, 3,4-seco-friedelan-3-oic acid, 3β-hydroxy-olean-9(11:12-diene and the mixture of α-amirin and β-amirin. β-sitosterol, the polymer gutta-percha, squalene and eicosanoic acid were also isolated. The chemical structures of these constituents were established by IR, 1H and 13C NMR spectral data. Crude extracts and the triterpenes were tested against Entamoeba histolytica, Giardia lamblia and Trichomonas vaginalis and no activity was observed under the in vitro assay conditions. The hexane, chloroform, ethyl acetate and ethanol crude extracts, and the constituent 3,4-seco-friedelan-3-oic acid and 28,29-dihydroxyfriedelan-3-one showed in vitro antimicrobial activity against Salmonella typhimurium, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus cereus, Listeria monocytogenes, Streptococcus sanguinis and Candida albicans.

  17. Heterogeneous ice nucleation in aqueous solutions: the role of water activity.

    Science.gov (United States)

    Zobrist, B; Marcolli, C; Peter, T; Koop, T

    2008-05-01

    Heterogeneous ice nucleation experiments have been performed with four different ice nuclei (IN), namely nonadecanol, silica, silver iodide and Arizona test dust. All IN are either immersed in the droplets or located at the droplets surface. The IN were exposed to various aqueous solutions, which consist of (NH4)2SO4, H2SO4, MgCl2, NaCl, LiCl, Ca(NO3)2, K2CO3, CH3COONa, ethylene glycol, glycerol, malonic acid, PEG300 or a NaCl/malonic acid mixture. Freezing was studied using a differential scanning calorimeter and a cold finger cell. The results show that the heterogeneous ice freezing temperatures decrease with increasing solute concentration; however, the magnitude of this effect is solute dependent. In contrast, when the results are analyzed in terms of the solution water activity a very consistent behavior emerges: heterogeneous ice nucleation temperatures for all four IN converge each onto a single line, irrespective of the nature of the solute. We find that a constant offset with respect to the ice melting point curve, Deltaaw,het, can describe the observed freezing temperatures for each IN. Such a behavior is well-known for homogeneous ice nucleation from supercooled liquid droplets and has led to the development of water-activity-based ice nucleation theory. The large variety of investigated solutes together with different general types of ice nuclei studied (monolayers, ionic crystals, covalently bound network-forming compounds, and a mixture of chemically different crystallites) underlines the general applicability of water-activity-based ice nucleation theory also for heterogeneous ice nucleation in the immersion mode. Finally, the ice nucleation efficiencies of the various IN, as well as the atmospheric implication of the developed parametrization are discussed.

  18. Do Training Programs Work? An Assessment of Pharmacists Activities in the Field of Chemical Dependency.

    Science.gov (United States)

    Brooks, Valerie G.; Brock, Tina Penick; Ahn, Jungeun

    2001-01-01

    Seeks to determine if pharmacists who attended a chemical dependency training program were performing more chemical dependency related activities. Results reveal that participants were more likely to perform the following activities: lecture to community groups about chemical dependency; participate in a pharmacists' recovery program; provide…

  19. Application of the Activity Framework for Assessing Aquatic Ecotoxicology Data for Organic Chemicals

    DEFF Research Database (Denmark)

    Thomas, Paul; Dawick, James; Lampi, Mark

    2015-01-01

    Toxicological research in the 1930s gave the first indications of the link between narcotic toxicity and the chemical activity of organic chemicals. More recently, chemical activity has been proposed as a novel exposure parameter that describes the fraction of saturation and that quantifies the p...

  20. Preparation of activated Carbons from extracted waste biomass by chemical activation

    International Nuclear Information System (INIS)

    Toteva, V.; Nickolov, R.

    2013-01-01

    Full text: Novel biomass precursors for the production of activated carbons (ACs) were studied. ACs were prepared from extracted coffee husks and extracted spent ground coffee - separately or as mixtures with 10, 20 and 30 mass % Bulgarian lignite coal. Activation by potassium hydroxide was employed for all samples. The results obtained show that the surface and porous parameters of the ACs depend on the nature of the initial materials used. The specific surface areas (BET) and the microporosities of ACs obtained from extracted spent ground coffee mixed with 20 mass % Bulgarian lignite coals, are greater than those of the ACs from extracted coffee husks. It is likely that the reason for this result is the chemical composition of the precursors. The coffee husks have less lignin and more holocellulose. The latter undergoes more significant destructive changes in the process of chemical activation. On the contrary, waste ground coffee precursors contain more lignin and less holocellulose. As a result, after the chemical activation, the carbons prepared from extracted spent ground coffee exhibit better porous parameters and higher specific surface areas. key words: activated carbons, extraction, waste biomass

  1. Chemical composition and antioxidant activities of Broussonetia papyrifera fruits.

    Directory of Open Access Journals (Sweden)

    Jie Sun

    Full Text Available Fruits of Broussonetia papyrifera from South China were analyzed for their total chemical composition, and antioxidant activities in ethanol and aqueous extracts. In the fruit of this plant, the crude protein, crude fat and carbohydrates was 7.08%, 3.72% and 64.73% of dry weight, respectively. The crude protein, crude fat and carbohydrates were 15.71%, 20.51% and 36.09% of dry weight, respectively. Fatty acid and amino acid composition of the fruit were analyzed. Unsaturated fatty acid concentration was 70.6% of the total fatty acids. The percentage of the essential amino acids (EAAs was 40.60% of the total amino acids. Furthermore, B. papyrifera fruit are rich in many mineral elements and vitamins. Total phenolic content was assessed using the Folin-Ciocalteau assay, whereas antioxidant activities were assessed by measuring the ability of the two extracts to scavenge DPPH radicals, inhibit peroxidation, and chelate ferric ions. Their reducing power was also assessed. Results indicated that the aqueous extract of B. papyrifera was a more potent reducing agent and radical-scavenger than the ethanol extract. GC-MS analysis of the ethanol extract showed the presence of some acid-containing compounds. The changes in total phenolic content and antioxidant capacity in B. papyrifera from four different regions grown under normal conditions were assessed. The antioxidant activity of different extracts was positively associated with their total phenolic content. These results suggest that the fruit of B. papyrifera could be used in dietary supplement preparations, or as a food additive, for nutritional gain, or to prevent oxidation in food products.

  2. Less is more: Sampling chemical space with active learning

    Science.gov (United States)

    Smith, Justin S.; Nebgen, Ben; Lubbers, Nicholas; Isayev, Olexandr; Roitberg, Adrian E.

    2018-06-01

    The development of accurate and transferable machine learning (ML) potentials for predicting molecular energetics is a challenging task. The process of data generation to train such ML potentials is a task neither well understood nor researched in detail. In this work, we present a fully automated approach for the generation of datasets with the intent of training universal ML potentials. It is based on the concept of active learning (AL) via Query by Committee (QBC), which uses the disagreement between an ensemble of ML potentials to infer the reliability of the ensemble's prediction. QBC allows the presented AL algorithm to automatically sample regions of chemical space where the ML potential fails to accurately predict the potential energy. AL improves the overall fitness of ANAKIN-ME (ANI) deep learning potentials in rigorous test cases by mitigating human biases in deciding what new training data to use. AL also reduces the training set size to a fraction of the data required when using naive random sampling techniques. To provide validation of our AL approach, we develop the COmprehensive Machine-learning Potential (COMP6) benchmark (publicly available on GitHub) which contains a diverse set of organic molecules. Active learning-based ANI potentials outperform the original random sampled ANI-1 potential with only 10% of the data, while the final active learning-based model vastly outperforms ANI-1 on the COMP6 benchmark after training to only 25% of the data. Finally, we show that our proposed AL technique develops a universal ANI potential (ANI-1x) that provides accurate energy and force predictions on the entire COMP6 benchmark. This universal ML potential achieves a level of accuracy on par with the best ML potentials for single molecules or materials, while remaining applicable to the general class of organic molecules composed of the elements CHNO.

  3. Safety- and Risk Analysis Activities in Chemical Industry in Europe

    Energy Technology Data Exchange (ETDEWEB)

    Kozine, Igor; Duijm, Nijs Jan; Lauridsen Kurt [Risoe National Laboratory, Roskilde (Denmark). Systems Analysis Department

    2001-07-01

    . In this respect there is a European and International mechanism of handling safety- and risk-related matters. So, the Organisation for Economic Co-operation and Development's (OECD) core objective on risk management is to support Member countries' efforts to develop national policies and actions, and, where appropriate, to develop and implement international risk management measures. In support of this objective, the OECD Risk Management Programme focuses on two areas: (1) developing methods and technical tools that can be used by OECD and Member countries to enhance their current risk management programmes; and (2) identifying specific chemical exposures of concern in Member countries and evaluating possible risk management opportunities. The current paper highlights the EU legislation on major accident hazards related to the chemical industry, differences in the national approaches to risk analyses in the process industry and European-scale activity in improving the understanding of the sources of uncertainty in risk assessments.

  4. Secondary organic aerosols. Chemical aging, hygroscopicity, and cloud droplet activation

    Energy Technology Data Exchange (ETDEWEB)

    Buchholz, Angela

    2011-07-06

    functional groups in this compound was adjusted to reproduce the observed growth curves. However, further information on surface tension and the ratio of the molecular mass and density of the solute is needed to predict activation behavior from hygroscopic growth measurements. A dependence of {kappa} on the ratio of primarily produced OH to initial VOC level was observed. The higher {kappa} values for low precursor concentrations could be attributed to a higher OH/VOC level. The detailed chemical composition of the gas-phase precursors had only little effect on {kappa}. In long term experiments there was no significant effect of the observed chemical aging of the particles on {kappa}. The observed low variability of {kappa} for biogenic SOA particles simplifies their treatment in global models as an average value of {kappa} = 0.1 can be used. (orig.)

  5. Plant polyphenols: chemical properties, biological activities, and synthesis.

    Science.gov (United States)

    Quideau, Stéphane; Deffieux, Denis; Douat-Casassus, Céline; Pouységu, Laurent

    2011-01-17

    Eating five servings of fruits and vegetables per day! This is what is highly recommended and heavily advertised nowadays to the general public to stay fit and healthy! Drinking green tea on a regular basis, eating chocolate from time to time, as well as savoring a couple of glasses of red wine per day have been claimed to increase life expectancy even further! Why? The answer is in fact still under scientific scrutiny, but a particular class of compounds naturally occurring in fruits and vegetables is considered to be crucial for the expression of such human health benefits: the polyphenols! What are these plant products really? What are their physicochemical properties? How do they express their biological activity? Are they really valuable for disease prevention? Can they be used to develop new pharmaceutical drugs? What recent progress has been made toward their preparation by organic synthesis? This Review gives answers from a chemical perspective, summarizes the state of the art, and highlights the most significant advances in the field of polyphenol research. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Chemical and thermal modulation of molecular motor activities

    Science.gov (United States)

    Hong, Weili

    Molecular motors of kinesin and dynein families are responsible for various intracellular activities, from long distance movement of organelles, vesicles, protein complexes, and mRNAs to powering mitotic processes. They can take nanometer steps using chemical energy from the hydrolysis of ATP (adenosine triphosphate), and their dysfunction is involved in many neurodegenerative diseases that require long distance transport of cargos. Here I report on the study of the properties of molecular motors at a single-molecule level using optical trappings. I first studied the inhibition properties of kinesin motors by marine natural compound adociasulfates. I showed that adociasulfates compete with microtubules for binding to kinesins and thus inhibit kinesins' activity. Although adociasulfates are a strong inhibitor for all kinesin members, they show a much higher inhibition effect for conventional kinesins than for mitotic kinesins. Thus adociasulfates can be used to specifically inhibit conventional kinesins. By comparing the inhibition of kinesins by two structurally similar adociasulfates, one can see that the negatively charged sulfate residue of adociasulfates can be replaced by other negative residues and thus make it possible for adociasulfate-derived compounds to be more cell permeable. Kinesins and dyneins move cargos towards opposite directions along a microtubule. Cargos with both kinesins and dyneins attached often move bidirectionally due to undergoing a tug-of-war between the oppositely moving kinesin and dynein motors. Here I studied the effect of temperature on microtubule-based kinesin and dynein motor transport. While kinesins' and dyneins' velocities are closely matched above 15 °C, below this temperature the dyneins' velocity decreases much faster than the kinesins'. The kinesins' and dyneins' forces do not measurably change with temperature. The results suggest that temperature has significant effects on bidirectional transport and can be used to

  7. The versatility of hot-filament activated chemical vapor deposition

    International Nuclear Information System (INIS)

    Schaefer, Lothar; Hoefer, Markus; Kroeger, Roland

    2006-01-01

    In the field of activated chemical vapor deposition (CVD) of polycrystalline diamond films, hot-filament activation (HF-CVD) is widely used for applications where large deposition areas are needed or three-dimensional substrates have to be coated. We have developed processes for the deposition of conductive, boron-doped diamond films as well as for tribological crystalline diamond coatings on deposition areas up to 50 cm x 100 cm. Such multi-filament processes are used to produce diamond electrodes for advanced electrochemical processes or large batches of diamond-coated tools and parts, respectively. These processes demonstrate the high degree of uniformity and reproducibility of hot-filament CVD. The usability of hot-filament CVD for diamond deposition on three-dimensional substrates is well known for CVD diamond shaft tools. We also develop interior diamond coatings for drawing dies, nozzles, and thread guides. Hot-filament CVD also enables the deposition of diamond film modifications with tailored properties. In order to adjust the surface topography to specific applications, we apply processes for smooth, fine-grained or textured diamond films for cutting tools and tribological applications. Rough diamond is employed for grinding applications. Multilayers of fine-grained and coarse-grained diamond have been developed, showing increased shock resistance due to reduced crack propagation. Hot-filament CVD is also used for in situ deposition of carbide coatings and diamond-carbide composites, and the deposition of non-diamond, silicon-based films. These coatings are suitable as diffusion barriers and are also applied for adhesion and stress engineering and for semiconductor applications, respectively

  8. 1324-IJBCS-Article-Tchakala Ibrahim

    African Journals Online (AJOL)

    KODJIO NORBERT

    nous a permis de déterminer la nature et les ..... chemical activation with K2CO3. Bioresour. Technol., 98: 145–149. Ahmad AA, Hameed BH. 2010. Effect of preparation conditions of activated carbon .... onto functionalized granular activated.

  9. Heat-activated Plasmonic Chemical Sensors for Harsh Environments

    Energy Technology Data Exchange (ETDEWEB)

    Carpenter, Michael [SUNY Polytechnic Inst., Albany, NY (United States); Oh, Sang-Hyun [Univ. of Minnesota, Minneapolis, MN (United States)

    2015-12-01

    A passive plasmonics based chemical sensing system to be used in harsh operating environments was investigated and developed within this program. The initial proposed technology was based on combining technologies developed at the SUNY Polytechnic Institute Colleges of Nanoscale Science and Engineering (CNSE) and at the University of Minnesota (UM). Specifically, a passive wireless technique developed at UM was to utilize a heat-activated plasmonic design to passively harvest the thermal energy from within a combustion emission stream and convert this into a narrowly focused light source. This plasmonic device was based on a bullseye design patterned into a gold film using focused ion beam methods (FIB). Critical to the design was the use of thermal stabilizing under and overlayers surrounding the gold film. These stabilizing layers were based on both atomic layer deposited films as well as metal laminate layers developed by United Technologies Aerospace Systems (UTAS). While the bullseye design was never able to be thermally stabilized for operating temperatures of 500oC or higher, an alternative energy harvesting design was developed by CNSE within this program. With this new development, plasmonic sensing results are presented where thermal energy is harvested using lithographically patterned Au nanorods, replacing the need for an external incident light source. Gas sensing results using the harvested thermal energy are in good agreement with sensing experiments, which used an external incident light source. Principal Component Analysis (PCA) was used to reduce the wavelength parameter space from 665 variables down to 4 variables with similar levels of demonstrated selectivity. The method was further improved by patterning rods which harvested energy in the near infrared, which led to a factor of 10 decrease in data acquisition times as well as demonstrated selectivity with a reduced wavelength data set. The combination of a plasmonic-based energy harvesting

  10. Chemical surface tuning electrocatalysis of redox-active nanoparticles

    DEFF Research Database (Denmark)

    Zhu, Nan; Ulstrup, Jens; Chi, Qijin

    This work focuses on electron transfer (ET) and electrocatalysis of inorganic hybrid Prussian blue nanoparticles (PBNPs, 6 nm) immobilized on different chemical surfaces. Through surface self-assembly chemistry, we have enabled to tune chemical properties of the electrode surface. Stable immobili...

  11. Chemical composition and antioxidant activity of essential oil ...

    African Journals Online (AJOL)

    In the present work, we studied the chemical composition of the essential oil of Cistus ladanifer and Cistus libanotis growing in Eastern Morocco. The essential oils were obtained by hydrodistillation and their chemical composition was analysed using gas chromatography- mass spectrometry (GC–MS). Camphene, borneol ...

  12. Chemical composition and antifungal activity of essential oils of ...

    African Journals Online (AJOL)

    The aim of this study was to determine the chemical composition of the essential oils of Algerian citrus. They were extracted by hydrodistillation from the leaves of citrus species (orange, Bigaradier, mandarin and lemon), using gas chromatography/mass spectrometry (GC/MS). Their chemical composition and antifungal ...

  13. Microbial dechlorination activity during and after chemical oxidant treatment

    Energy Technology Data Exchange (ETDEWEB)

    Doğan-Subaşı, Eylem [Flemish Institute for Technological Research (VITO), Separation and Conversion Technology, Boeretang 200, 2400 Mol (Belgium); Laboratory of Microbial Ecology and Technology (LabMET), Ghent University, Coupure Links 653, 9000 Gent (Belgium); Bastiaens, Leen, E-mail: leen.bastiaens@vito.be [Flemish Institute for Technological Research (VITO), Separation and Conversion Technology, Boeretang 200, 2400 Mol (Belgium); Boon, Nico [Laboratory of Microbial Ecology and Technology (LabMET), Ghent University, Coupure Links 653, 9000 Gent (Belgium); Dejonghe, Winnie [Flemish Institute for Technological Research (VITO), Separation and Conversion Technology, Boeretang 200, 2400 Mol (Belgium)

    2013-11-15

    Highlights: • Combined treatment was possible below 0.5 g/L of KMnO{sub 4} and 1 g/L of Na{sub 2}S{sub 2}O{sub 8}. • By-products SO{sub 4}{sup 2−} and MnO{sub 2(s)} had inhibitory effects on dehalogenating bacteria. • Oxidation reduction potential (ORP) was identified as a crucial parameter for recovery of oxidant exposed cells. • Bioaugmentation is a necessity at 0.5 g/L of KMnO{sub 4} and 1 g/L of Na{sub 2}S{sub 2}O{sub 8} and above. -- Abstract: Potassium permanganate (PM) and sodium persulfate (PS) are used in soil remediation, however, their compatibility with a coinciding or subsequent biotreatment is poorly understood. In this study, different concentrations of PM (0.005–2 g/L) and PS (0.01–4.52 g/L) were applied and their effects on the abundance, activity, and reactivation potential of a dechlorinating enrichment culture were investigated. Expression of the tceA, vcrA and 16S rRNA genes of Dehalococcoides spp. were detected at 0.005–0.01 g/L PM and 0.01–0.02 g/L PS. However, with 0.5–2 g/L PM and 1.13–4.52 g/L PS no gene expression was recorded, neither were indicator molecules for total cell activity (Adenosine triphosphate, ATP) detected. Dilution did not promote the reactivation of the microbial cells when the redox potential was above −100 mV. Similarly, inoculated cells did not dechlorinate trichloroethene (TCE) above −100 mV. When the redox potential was decreased to −300 mV and the reactors were bioaugmented for a second time, dechlorination activity recovered, but only in the reactors with 1.13 and 2.26 g/L PS. In conclusion, our results show that chemical oxidants can be combined with a biotreatment at concentrations below 0.5 g/L PM and 1 g/L PS.

  14. Effect of textural and chemical characteristics of activated carbons on phenol adsorption in aqueous solutions

    OpenAIRE

    Vargas Diana P.; Giraldo Liliana; Moreno-Piraján Juan Carlos

    2017-01-01

    The effect of textural and chemical properties such as: surface area, pore volume and chemical groups content of the granular activated carbon and monoliths on phenol adsorption in aqueous solutions was studied. Granular activated carbon and monolith samples were produced by chemical activation. They were characterized by using N2 adsorption at 77 K, CO2 adsorption at 273 K, Boehm Titrations and immersion calorimetry in phenol solutions. Microporous materials with different pore size distribu...

  15. Advanced deposition model for thermal activated chemical vapor deposition

    Science.gov (United States)

    Cai, Dang

    Thermal Activated Chemical Vapor Deposition (TACVD) is defined as the formation of a stable solid product on a heated substrate surface from chemical reactions and/or dissociation of gaseous reactants in an activated environment. It has become an essential process for producing solid film, bulk material, coating, fibers, powders and monolithic components. Global market of CVD products has reached multi billions dollars for each year. In the recent years CVD process has been extensively used to manufacture semiconductors and other electronic components such as polysilicon, AlN and GaN. Extensive research effort has been directed to improve deposition quality and throughput. To obtain fast and high quality deposition, operational conditions such as temperature, pressure, fluid velocity and species concentration and geometry conditions such as source-substrate distance need to be well controlled in a CVD system. This thesis will focus on design of CVD processes through understanding the transport and reaction phenomena in the growth reactor. Since the in situ monitor is almost impossible for CVD reactor, many industrial resources have been expended to determine the optimum design by semi-empirical methods and trial-and-error procedures. This approach has allowed the achievement of improvements in the deposition sequence, but begins to show its limitations, as this method cannot always fulfill the more and more stringent specifications of the industry. To resolve this problem, numerical simulation is widely used in studying the growth techniques. The difficulty of numerical simulation of TACVD crystal growth process lies in the simulation of gas phase and surface reactions, especially the latter one, due to the fact that very limited kinetic information is available in the open literature. In this thesis, an advanced deposition model was developed to study the multi-component fluid flow, homogeneous gas phase reactions inside the reactor chamber, heterogeneous surface

  16. Calculation of neutron activation discriminating the chemical weapons underground using Monte Carlo methods

    International Nuclear Information System (INIS)

    Shen Chunxia; Qian Jianfu; Zhang Wenzhong

    2003-01-01

    This paper mainly calculate neutron activation discriminating the chemical weapons underground, and analyses the factors that soil influence discrimination, finally we conclude soil can not influence discrimination. (authors)

  17. Development of Bicarbonate-Activated Peroxide as a Chemical and Biological Warfare Agent Decontaminant

    National Research Council Canada - National Science Library

    Richardson, David E

    2006-01-01

    ...) and other chemistry for the decontamination of chemical and biological warfare agents. The mechanism of formation of the active oxidant, peroxymonocarbonate, has been investigated in detail. New surfoxidants...

  18. INAA and chemical analysis of water and sediments sampled in 1996 from the Romanian sector of the Danube river

    International Nuclear Information System (INIS)

    Pantelica, A.; Georgescu, I.I.; Oprica, M.H.I.; Borcia, C.

    1999-01-01

    Water and sediment samples collected during spring 1996 from 20 sampling sites of the Romanian sector of the Danube river and the Black Sea coast were analyzed by instrumental neutron activation analysis (INAA) and by chemical methods to determine major, minor and trace element contents. The concentrations of 43 elements (Ag, Al, As, Au, Ba, Br, Ca, Ce, Cl, Co, Cr, Cu, Cs, Eu, Fe, Ga, Hf, Hg, K, La, Lu, Mg, Mn, Mo, Na, Nd, Ni, Rb, Sb, Sc, Se, Sm, Sr, Ta, Tb, Ti, Th, U, V, W, Yb, Zr, Zn) were investigated by INAA at WWR-S reactor in Bucharest. Chemical methods were used to determine the content of P 2 O 5 and SiO 2 in sediments. For INAA, the water residues and sediment samples were irradiated at the WWR-S reactor in Bucharest at a neutron fluence rate of 2.3·10 12 cm -2 s -1 . As standards, reference materials IAEA-Soil 7 and WTM (sludge from city water treatment, from the Institute of Radioecology and Applied Nuclear Techniques Kosice, Slovakia) as well as chemical compounds of Al, Ca, Mg, V were used. Mono-standard method was applied in the case of Ti and Sr (Cl and Zn as standards, respectively). By chemical methods, the amount of SiO 2 was determined in sediment samples after the treatment with concentrated HCl and residuum dis-aggregation by fusion (melting with a mixture of Na 2 CO 3 and K 2 CO 3 ). Phosphorus was determined by spectrophotometry with ammonium molybdate and by reduction with ascorbic acid. It can be seen that, both for water and sediment samples, the highest contents of Al, Co, Cs, Fe, Rb, and Sb were found at the sites located upstream the Portile de Fier dam: at Turnu Severin (for water) and Orsova (for sediments). Ag, Au, Ni, Yb, Zr were determined only in some of the water samples at the following concentration levels: ng L -1 (Au, Lu), tens of ng L -1 (Ag, Tb, Yb), hundreds of ng L -1 (Ag), μg L -1 (Ni, Zr), tens of μg L -1 (Ni, Ti). From a comparison with results of our previous studies for the Danube bottom sediments, no significant

  19. Chemical constituents and antihistamine activity of Bixa orellana leaf extract

    Directory of Open Access Journals (Sweden)

    Yong Yoke Keong

    2013-02-01

    Full Text Available Abstract Background Bixa orellana L. has been traditionally used in Central and South America to treat a number of ailments, including internal inflammation, and in other tropical countries like Malaysia as treatment for gastric ulcers and stomach discomfort. The current study aimed to determine the major chemical constituents of the aqueous extract of B. orellana (AEBO and to evaluate the antihistamine activity of AEBO during acute inflammation induced in rats. Methods Acute inflammation was produced by subplantar injection of 0.1 mL of 0.1% histamine into the right hind paw of each rat in the control and treatment groups. The degree of edema was measured before injection and at the time points of 30, 60, 120, 180, 240 and 300 min after injection. Changes of peritoneal vascular permeability were studied using Evans blue dye as a detector. Vascular permeability was evaluated by the amount of dye leakage into the peritoneal cavity in rats. To evaluate the inhibitory effect of AEBO on biochemical mediators of vascular permeability, the levels of nitric oxide (NO and vascular endothelial growth factor (VEGF were determined in histamine-treated paw tissues. The major constituents of AEBO were determined by gas chromatography–mass spectrometry (GC-MS analysis. Results AEBO produced a significant inhibition of histamine-induced paw edema starting at 60 min time point, with maximal percentage of inhibition (60.25% achieved with a dose of 150 mg/kg of AEBO at 60 min time point. Up to 99% of increased peritoneal vascular permeability produced by histamine was successfully suppressed by AEBO. The expression of biochemical mediators of vascular permeability, NO and VEGF, was also found to be downregulated in the AEBO treated group. Gas chromatography–mass spectrometry (GC-MS analysis revealed that the major constituent in AEBO was acetic acid. Conclusions The experimental findings demonstrated that the anti-inflammatory activity of AEBO was

  20. 76 FR 7841 - Agency Information Collection Activities; Proposed Collections; Toxic Chemical Release Reporting...

    Science.gov (United States)

    2011-02-11

    ... agencies, and others to promote reductions in toxic chemical releases. Industrial facilities use the TRI... Activities; Proposed Collections; Toxic Chemical Release Reporting; Request for Comments on Proposed Renewal... the individual listed in the preceding FOR FURTHER INFORMATION CONTACT section. Title: Toxic Chemical...

  1. Antimicrobial activity and chemical compositions of Turkish propolis ...

    African Journals Online (AJOL)

    negative bacteria and its chemical composition were evaluated by the method of agar-well diffusion and GC-MS, respectively. Some typical compounds samples were identified in the propolis samples. Principal component analysis revealed that the ...

  2. Chemical compositions and antimicrobial activity of twig essential ...

    African Journals Online (AJOL)

    Aghomotsegin

    2016-03-09

    Mar 9, 2016 ... The chemical composition of twig essential oils of Xylopia malayana, Xylopia elliptica and Xylopia fusca were analyzed ... brown or dark green in colors and fragrant. .... extraction used and geographic origin of plant studied.

  3. Assessment of activated carbon prepared from corncob by chemical activation with phosphoric acid

    Directory of Open Access Journals (Sweden)

    Gamal O. El-Sayed

    2014-09-01

    Full Text Available Corncob, which is the main waste from corn agricultures in Egypt, has been used as a raw material for the preparation of different activated carbons. Activated carbons (ACs were prepared by chemical activation with concentrated H3PO4 acid; followed by pyrolysis at 400, 500 and 600 °C. Different ACs have been used for the removal of methylene blue (MB dye from aqueous solutions. Batch adsorption experiments were performed as a function of initial dye concentration, contact time, adsorbent dose and pH. Adsorption data were modeled using the Langmuir and Freundlich adsorption isotherms. Adsorption of MB on AC1 (R2=0.9868 and AC2 (R2=0.9810 followed Langmuir model with maximum monolayer sorption capacity of 28.65 and 17.57 mg/g, respectively. Adsorption onto AC3 was better fitted to Freundlich isotherm model (R2=0.9823.

  4. CHEMICALS

    CERN Multimedia

    Medical Service

    2002-01-01

    It is reminded that all persons who use chemicals must inform CERN's Chemistry Service (TIS-GS-GC) and the CERN Medical Service (TIS-ME). Information concerning their toxicity or other hazards as well as the necessary individual and collective protection measures will be provided by these two services. Users must be in possession of a material safety data sheet (MSDS) for each chemical used. These can be obtained by one of several means : the manufacturer of the chemical (legally obliged to supply an MSDS for each chemical delivered) ; CERN's Chemistry Service of the General Safety Group of TIS ; for chemicals and gases available in the CERN Stores the MSDS has been made available via EDH either in pdf format or else via a link to the supplier's web site. Training courses in chemical safety are available for registration via HR-TD. CERN Medical Service : TIS-ME :73186 or service.medical@cern.ch Chemistry Service : TIS-GS-GC : 78546

  5. Chemical behavior of tungsten trifluorophosphines following neutron activation

    International Nuclear Information System (INIS)

    Bottomley, L.D.; Clark, R.J.

    1988-01-01

    The chemical reactions that follow neutron capture have been studied for a series of tungsten trifluorophosphine carbonyls. The molecular distribution of 187 W was determined by gas chromatographic separation using scintillation detection. The chemical behavior of these compounds was examined in the condensed phase and the gas phase, both with and without excess PF 3 or CO. The retention of the parent species was measured as well as the formation of any scrambled species W(PF 3 ) x (CO) 6-x in all experiments. The results of irradiations done in condensed phase with no excess ligands were modeled by a Simplex iterative routine to calculate the distribution of recoil fragments. (orig.)

  6. 75 FR 69630 - Impact of Implementation of the Chemical Weapons Convention on Commercial Activities Involving...

    Science.gov (United States)

    2010-11-15

    ... Biotechnology,'' calls for the President to certify to Congress on an annual basis that ``the legitimate commercial activities and interests of chemical, biotechnology, and pharmaceutical firms in the United States... commercial activities and interests of chemical, biotechnology, and pharmaceutical firms in the United States...

  7. Activity guided isolation of chemical constituents from the ...

    African Journals Online (AJOL)

    In this study we investigated the chemical constituents of bioactive methanol extract of Euphorbia schimperi C. Presl. For this the methanol extract was fractionated into 20, 40, 60, 80% MeOH in CHCl3, and 100% MeOH fractions respectively by vacuum liquid chromatography. Excision wound surface of the animals were ...

  8. Biodegradation of Organophosphate Chemical Warfare Agents by Activated Sludge

    Science.gov (United States)

    2012-03-01

    bronchoconstriction Bladder (M) Urinary frequency, incontinence Cardiovascular system (M) Bradycardia, hypotension Cardiovascular system (N...conventional weapons: their cost and stability, simplicity of production, pound for pound potency and fear factor (Hill et al., 2008a). Compared to...Chemical agents, especially nerve agents, have a dramatic fear factor due to the symptoms they cause. Witnessing civilians violently convulsing

  9. Chemical composition and antifungal activity of essential oils of ...

    African Journals Online (AJOL)

    patrick

    2015-03-25

    Mar 25, 2015 ... A. sp and F. sp were screwed using food poisoning technique. (Grover and ... of the fungi colonies of the sets of treatment and diameter of positive ..... Chemical variability of peel and leaf essential oils of sour orange. Flav.

  10. activity guided isolation of chemical constituents from the ...

    African Journals Online (AJOL)

    MeOH fraction was subjected to various chromatographic techniques led to the isolation of miquelianin (1), kaempferol 3-O-glucuronide (2) and quercitrin (3). Compounds (1-3) were isolated from this plant for the first time. KEY WORDS: Euphorpia schimperi C. Presl, Wound healing, Chromatographic techniques, Chemical.

  11. Chemical compositions and antimicrobial activity of twig essential ...

    African Journals Online (AJOL)

    Aghomotsegin

    2016-03-09

    Mar 9, 2016 ... The chemical composition of twig essential oils of Xylopia malayana, Xylopia elliptica and Xylopia fusca ... Volatile constituents and bioactivity studies are available in the literature on Xylopia aethiopica (Issakou et al., 2014;. Sylvain et al, 2014; Vyry et al, 2014), Xylopia longifolia. (Fourier et al, 1993), ...

  12. Adsorption studies of methylene blue and phenol onto vetiver roots activated carbon prepared by chemical activation.

    Science.gov (United States)

    Altenor, Sandro; Carene, Betty; Emmanuel, Evens; Lambert, Jacques; Ehrhardt, Jean-Jacques; Gaspard, Sarra

    2009-06-15

    Vetiver roots have been utilized for the preparation of activated carbon (AC) by chemical activation with different impregnation ratios of phosphoric acid, X(P) (gH(3)PO(4)/g precursor): 0.5:1; 1:1 and 1.5:1. Textural characterization, determined by nitrogen adsorption at 77K shows that mixed microporous and mesoporous structures activated carbons (ACs) with high surface area (>1000 m(2)/g) and high pore volume (up to 1.19 cm(3)/g) can be obtained. The surface chemical properties of these ACs were investigated by X-ray photoelectron spectroscopy (XPS) and Boehm titration. Their textural and chemical characteristics were compared to those of an AC sample obtained by steam activation of vetiver roots. Classical molecules used for characterizing liquid phase adsorption, phenol and methylene blue (MB), were used. Adsorption kinetics of MB and phenol have been studied using commonly used kinetic models, i.e., the pseudo-first-order model, the pseudo-second-order model, the intraparticle diffusion model and as well the fractal, BWS (Brouers, Weron and Sotolongo) kinetic equation. The correlation coefficients (R(2)) and the normalized standard deviation Deltaq (%) were determined showing globally, that the recently derived fractal kinetic equation could best describe the adsorption kinetics for the adsorbates tested here, indicating a complex adsorption mechanism. The experimental adsorption isotherms of these molecules on the activated carbon were as well analysed using four isotherms: the classical Freundlich, Langmuir, Redlich-Peterson equations, but as well the newly published deformed Weibull Brouers-Sotolongo isotherm. The results obtained from the application of the equations show that the best fits were achieved with the Brouers-Sotolongo equation and with the Redlich-Peterson equation. Influence of surface functional groups towards MB adsorption is as well studied using various ACs prepared from vetiver roots and sugar cane bagasse. Opposite effects governing MB

  13. Enrichment: CRISLA [chemical reaction by isotope selective activation] aims to reduce costs

    International Nuclear Information System (INIS)

    Eerkens, J.W.

    1989-01-01

    Every year, more than $3 billion is spent on enriching uranium. CRISLA (Chemical Reaction by Isotope Selective Activation) uses a laser-catalyzed chemical reaction which, its proponents claim, could substantially reduce these costs. In CRISLA, an infrared CO laser illuminates the intracavity reaction cell (IC) at a frequency tuned to excite primarily UF 6 . When UF 6 and co-reactant RX are passed through the IC, the tuned laser photons preferentially enhance the reaction of UF 6 with RX ten-thousand-fold over the thermal reaction rate. Thus the laser serves as an activator and the chemical energy for separation is largely chemical. (author)

  14. Data on chemical activation of Wnt/β-catenin during axolotl limb regeneration

    Directory of Open Access Journals (Sweden)

    Sabina Wischin

    2017-04-01

    Full Text Available Limb amputation in axolotls was performed to obtain data demonstrating that a chemical agonist of Wnt (int-related protein/β-catenin signalling can have a role in axolotl limb regeneration (Wischin et al., 2017 [1]. The data revealed that active β-catenin protein was present during limb regeneration in some Leydig cells in the epithelium; after the chemical treatment, it was observed in more Leydig cells. In addition, the chemical agonist of Wnt generated distinct limb malformation.

  15. Chemical signal activation of an organocatalyst enables control over soft material formation.

    Science.gov (United States)

    Trausel, Fanny; Maity, Chandan; Poolman, Jos M; Kouwenberg, D S J; Versluis, Frank; van Esch, Jan H; Eelkema, Rienk

    2017-10-12

    Cells can react to their environment by changing the activity of enzymes in response to specific chemical signals. Artificial catalysts capable of being activated by chemical signals are rare, but of interest for creating autonomously responsive materials. We present an organocatalyst that is activated by a chemical signal, enabling temporal control over reaction rates and the formation of materials. Using self-immolative chemistry, we design a deactivated aniline organocatalyst that is activated by the chemical signal hydrogen peroxide and catalyses hydrazone formation. Upon activation of the catalyst, the rate of hydrazone formation increases 10-fold almost instantly. The responsive organocatalyst enables temporal control over the formation of gels featuring hydrazone bonds. The generic design should enable the use of a large range of triggers and organocatalysts, and appears a promising method for the introduction of signal response in materials, constituting a first step towards achieving communication between artificial chemical systems.Enzymes regulated by chemical signals are common in biology, but few such artificial catalysts exist. Here, the authors design an aniline catalyst that, when activated by a chemical trigger, catalyses formation of hydrazone-based gels, demonstrating signal response in a soft material.

  16. Recovery of microbial diversity and activity during bioremediation following chemical oxidation of diesel contaminated soils

    NARCIS (Netherlands)

    Sutton, N.B.; Langenhoff, A.A.M.; Hidalgo Lasso, D.; Zaan, van der B.M.; Gaans, van P.; Maphosa, F.; Smidt, H.; Grotenhuis, J.T.C.; Rijnaarts, H.H.M.

    2014-01-01

    To improve the coupling of in situ chemical oxidation and in situ bioremediation, a systematic analysis was performed of the effect of chemical oxidation with Fenton's reagent, modified Fenton's reagent, permanganate, or persulfate, on microbial diversity and activity during 8 weeks of incubation in

  17. Neutron activation analysis for chemical characterization of Brazilian oxo-biodegradable plastics

    International Nuclear Information System (INIS)

    Mateus Eugenio Boscaro; De Nadai Fernandes, E.A.; Marcio Arruda Bacchi; Luis Gustavo Cofani dos Santos; Cofani dos Santos, S.N.S.; Sandra Mara Martins-Franchetti

    2015-01-01

    The chemical characterization of oxo-biodegradable plastic bags was performed by neutron activation analysis. The presence of several chemical elements (As, Br, Ca, Co, Cr, Fe, Hf, K, La, Na, Sb, Sc, Ta and Zn) with large variability of mass fractions amongst samples indicates that these plastics receive additives and may have been contaminated during manufacturing process thereby becoming potential environmental pollutants. (author)

  18. Quinones from plants of northeastern Brazil: structural diversity, chemical transformations, NMR data and biological activities.

    Science.gov (United States)

    Lemos, Telma L G; Monte, Francisco J Q; Santos, Allana Kellen L; Fonseca, Aluisio M; Santos, Hélcio S; Oliveira, Mailcar F; Costa, Sonia M O; Pessoa, Otilia D L; Braz-Filho, Raimundo

    2007-05-20

    The present review focus in quinones found in species of Brazilian northeastern Capraria biflora, Lippia sidoides, Lippia microphylla and Tabebuia serratifolia. The review cover ethnopharmacological aspects including photography of species, chemical structure feature, NMR datea and biological properties. Chemical transformations of lapachol to form enamine derivatives and biological activities are discussed.

  19. Mathematical Modeling of Tin-Free Chemically-Active Antifouling Paint Behavior

    DEFF Research Database (Denmark)

    Yebra, Diego Meseguer; Kiil, Søren; Dam-Johansen, Kim

    2006-01-01

    Mathematical modeling has been used to characterize and validate the working mechanisms of tin-free, chemically-active antifouling (AF) paints. The model-based analysis of performance data from lab-scale rotary experiments has shown significant differences between antifouling technologies...... of Chemical Engineers....

  20. 77 FR 75145 - Impact of the Implementation of the Chemical Weapons Convention (CWC) on Commercial Activities...

    Science.gov (United States)

    2012-12-19

    ... interests of chemical, biotechnology, and pharmaceutical firms in the United States are not being... commercial activities and interests of chemical, biotechnology, and pharmaceutical firms in the United States... conditions to its ratification. Condition 9, titled ``Protection of Advanced Biotechnology,'' calls for the...

  1. Chemical composition and antimicrobial activity of the essential oil ...

    African Journals Online (AJOL)

    GREGO

    2007-03-19

    Mar 19, 2007 ... Chavan SR, Nikam ST (1982). Mosquito larvicidal activity ... Iwalokun BA, Gbenle GO, Adewole TA, Smith SI, Akinsinde KA,. Omonigbehin EA (2003). ... Brazilian Amazon. Ziet. Naturtorsch., 45c, 1073-1076;CA, 113: 229893.

  2. Role of human neurobehavioural tests in regulatory activity on chemicals

    Science.gov (United States)

    Stephens, R.; Barker, P.

    1998-01-01

    Psychological performance tests have been used since the mid-1960s in occupational and environmental health toxicology. The interpretation of significantly different test scores in neurobehavioural studies is not straightforward in the regulation of chemicals. This paper sets out some issues which emerged from discussions at an international workshop, organised by the United Kingdom Health and Safety Executive (HSE), to discuss differences in interpretation of human neurobehavioural test data in regulatory risk assessments. The difficulties encountered by regulators confronted with neurobehavioural studies seem to be twofold; some studies lack scientific rigor; other studies, although scientifically sound, are problematic because it is not clear what interpretation to place on the results. Issues relating to each of these points are discussed. Next, scenarios within which to consider the outcomes of neurobehavioural studies are presented. Finally, conclusions and recommendations for further work are put forward.   PMID:9624273

  3. Chemical Constituents of Descurainia sophia L. and its Biological Activity

    Directory of Open Access Journals (Sweden)

    Nawal H. Mohamed

    2009-01-01

    Full Text Available Seven coumarin compounds were isolated for the first time from the aerial parts of DescurainiaSophia L. identified as scopoletine, scopoline, isoscopoline, xanthtoxol, xanthtoxin, psoralene and bergaptane.Three flavonoids namely kaempferol, quercetine and isorhamnetine and three terpenoid compounds -sitosterol-amyrine and cholesterol were also isolated and identified by physical and chemical methods; melting point, Rfvalues, UV and 1H NMR spectroscopy. Qualitative and quantitative analyses of free and protein amino acidsusing amino acid analyzer were performed. The plant contains 15 amino acids as free and protein amino acidswith different range of concentrations. Fatty acid analysis using GLC, revealed the presence of 10 fatty acids,the highest percentage was palmitic acid (27.45 % and the lowest was lauric acid (0.13%. Biological screeningof alcoholic extract showed that the plant is highly safe and has analgesic, antipyretic and anti-inflammatoryeffects.

  4. activity guided isolation of chemical constituents from the ...

    African Journals Online (AJOL)

    Acer truncatum Bunge by high-speed counter-current chromatography. J. Chromatogr. A. 2005, 1070, 211–214. 11. Morton, J.J.; Malone, M.H. Evaluation of vulneray activity by an open wound procedure in rats. Arch.Int. Pharmacodyn. Ther. 1972, 196, 117–126. 12. Dash, G.K.; Murthy, P.N. Studies on wound healing activity ...

  5. Hydrogeology, chemical and microbial activity measurement through deep permafrost

    Energy Technology Data Exchange (ETDEWEB)

    Stotler, R.L.; Frape, S.K.; Freifeld, B.M.; Holden, B.; Onstott, T.C.; Ruskeeniemi, T.; Chan, E.

    2010-04-01

    Little is known about hydrogeochemical conditions beneath thick permafrost, particularly in fractured crystalline rock, due to difficulty in accessing this environment. The purpose of this investigation was to develop methods to obtain physical, chemical, and microbial information about the subpermafrost environment from a surface-drilled borehole. Using a U-tube, gas and water samples were collected, along with temperature, pressure, and hydraulic conductivity measurements, 420 m below ground surface, within a 535 m long, angled borehole at High Lake, Nunavut, Canada, in an area with 460-m-thick permafrost. Piezometric head was well above the base of the permafrost, near land surface. Initial water samples were contaminated with drill fluid, with later samples <40% drill fluid. The salinity of the non-drill fluid component was <20,000 mg/L, had a Ca/Na ratio above 1, with {delta}{sup 18}O values {approx}5{per_thousand} lower than the local surface water. The fluid isotopic composition was affected by the permafrost-formation process. Nonbacteriogenic CH{sub 4} was present and the sample location was within methane hydrate stability field. Sampling lines froze before uncontaminated samples from the subpermafrost environment could be obtained, yet the available time to obtain water samples was extended compared to previous studies. Temperature measurements collected from a distributed temperature sensor indicated that this issue can be overcome easily in the future. The lack of methanogenic CH{sub 4} is consistent with the high sulfate concentrations observed in cores. The combined surface-drilled borehole/U-tube approach can provide a large amount of physical, chemical, and microbial data from the subpermafrost environment with few, controllable, sources of contamination.

  6. Hydrogeology, chemical and microbial activity measurement through deep permafrost.

    Science.gov (United States)

    Stotler, Randy L; Frape, Shaun K; Freifeld, Barry M; Holden, Brian; Onstott, Tullis C; Ruskeeniemi, Timo; Chan, Eric

    2011-01-01

    Little is known about hydrogeochemical conditions beneath thick permafrost, particularly in fractured crystalline rock, due to difficulty in accessing this environment. The purpose of this investigation was to develop methods to obtain physical, chemical, and microbial information about the subpermafrost environment from a surface-drilled borehole. Using a U-tube, gas and water samples were collected, along with temperature, pressure, and hydraulic conductivity measurements, 420 m below ground surface, within a 535 m long, angled borehole at High Lake, Nunavut, Canada, in an area with 460-m-thick permafrost. Piezometric head was well above the base of the permafrost, near land surface. Initial water samples were contaminated with drill fluid, with later samples <40% drill fluid. The salinity of the non-drill fluid component was <20,000 mg/L, had a Ca/Na ratio above 1, with δ(18) O values ∼5‰ lower than the local surface water. The fluid isotopic composition was affected by the permafrost-formation process. Nonbacteriogenic CH(4) was present and the sample location was within methane hydrate stability field. Sampling lines froze before uncontaminated samples from the subpermafrost environment could be obtained, yet the available time to obtain water samples was extended compared to previous studies. Temperature measurements collected from a distributed temperature sensor indicated that this issue can be overcome easily in the future. The lack of methanogenic CH(4) is consistent with the high sulfate concentrations observed in cores. The combined surface-drilled borehole/U-tube approach can provide a large amount of physical, chemical, and microbial data from the subpermafrost environment with few, controllable, sources of contamination. Copyright © 2010 The Author(s). Journal compilation © 2010 National Ground Water Association.

  7. Chemically modified carboxypeptidase Y with increased amidase activity

    International Nuclear Information System (INIS)

    Breddam, K.

    1984-01-01

    Treatment of carboxypeptidase Y with 14 C-iodoacetamide caused a drastic reduction in the peptidase activity towards FA-Phe-Leu-OH while the esterase activity towards FA-Phe-OMe, the amidase activity towards FA-Phe-NH 2 and the peptidyl amino acid amide hydrolase activity towards FA-Phe-Gly-NH 2 were much less affected. The loss of peptidase activity could be correlated with the incorporation of a single equivalent of reagent and it was demonstrated that the site of reaction was a methionyl residue, thus forming a sulfonium derivative. Analogous methionyl modifications were performed: carboxypeptidase Y modified with phenacylbromide hydrolysed substrates with bulky leaving groups in the P position, i.e. -OEt, -OBzl, -Gly-NH 2 ,-Gly-OH, and -Leu-OH, at reduced rates while substrates with small groups in that position, i.e. -OMe and -NH 2 , were hydrolysed with increased rates. These results indicate that the methionyl residue modified by phenacylbromide is located in the S binding site of the enzyme. Similar results were obtained with carboxypeptidase Y modified with m-nitrophen- acylbromide and p-nitrophenacylbromide. The increase in amidase activity and decrease in peptidyl amino acid amide hydrolase activity of carboxypeptidase Y following modification with phenacylbromide, m-nitrophenacylbromide, and p-nitrophenacylbromide was exploited in deamidation of peptide amides. These modified enzymes deamidated peptide amides with the exception of those containing a C-terminal glycyl or seryl residue in yields of 80-100% which is significantly higher than with unmodified carboxypeptidase Y. (author)

  8. Foeniculum vulgare essential oils: chemical composition, antioxidant and antimicrobial activities.

    Science.gov (United States)

    Miguel, Maria Graça; Cruz, Cláudia; Faleiro, Leonor; Simões, Mariana T F; Figueiredo, Ana Cristina; Barroso, José G; Pedro, Luis G

    2010-02-01

    The essential oils from Foeniculum vulgare commercial aerial parts and fruits were isolated by hydrodistillation, with different distillation times (30 min, 1 h, 2 h and 3 h), and analyzed by GC and GC-MS. The antioxidant ability was estimated using four distinct methods. Antibacterial activity was determined by the agar diffusion method. Remarkable differences, and worrying from the quality and safety point of view, were detected in the essential oils. trans-Anethole (31-36%), alpha-pinene (14-20%) and limonene (11-13%) were the main components of the essentials oil isolated from F. vulgare dried aerial parts, whereas methyl chavicol (= estragole) (79-88%) was dominant in the fruit oils. With the DPPH method the plant oils showed better antioxidant activity than the fruits oils. With the TBARS method and at higher concentrations, fennel essential oils showed a pro-oxidant activity. None of the oils showed a hydroxyl radical scavenging capacity > 50%, but they showed an ability to inhibit 5-lipoxygenase. The essential oils showed a very low antimicrobial activity. In general, the essential oils isolated during 2 h were as effective, from the biological activity point of view, as those isolated during 3 h.

  9. Chemical composition and antibacterial activity of essential oils against human pathogenic bacteria

    NARCIS (Netherlands)

    Sokovic, M.; Marin, P.D.; Brkic, D.; Griensven, van L.J.L.D.

    2008-01-01

    The chemical composition and antibacterial activity of essential oils from 10 aromatic plants Matricaria chamommilla, Mentha piperita, M. spicata, Lavandula angustifolia, Ocimum basilicum, Thymus vulgaris, Origanum vulgare, Salvia officinalis, Citrus limon and C. aurantium have been determined.

  10. 75 FR 68370 - Agency Information Collection Activities: Office of Infrastructure Protection; Chemical Security...

    Science.gov (United States)

    2010-11-05

    ... DEPARTMENT OF HOMELAND SECURITY National Protection and Programs Directorate [Docket No. DHS-2010-0071] Agency Information Collection Activities: Office of Infrastructure Protection; Chemical Security...: The Department of Homeland Security (DHS), National Protection and Programs Directorate (NPPD), Office...

  11. Adsorption and Pore of Physical-Chemical Activated Coconut Shell Charcoal Carbon

    Science.gov (United States)

    Budi, E.; Umiatin, U.; Nasbey, H.; Bintoro, R. A.; Wulandari, Fi; Erlina, E.

    2018-04-01

    The adsorption of activated carbon of coconut shell charcoal on heavy metals (Cu and Fe) of the wastewater and its relation with the carbon pore structure was investigated. The coconut shell was pyrolized in kiln at temperature about 75 - 150 °C for about 6 hours to produce charcoal and then shieved into milimeter sized granule particles. Chemical activation was done by immersing the charcoal into chemical solution of KOH, NaOH, HCl and H3PO4, with various concentration. The activation was followed by physical activation using horizontal furnace at 400°C for 1 hours in argon gas environment with flow rate of 200 kg/m3. The surface morphology of activated carbon were characterized by using Scanning Electron Microscopy (SEM). Wastewater was made by dissolving CuSO4.5H2O and FeSO4.7H2O into aquades. The metal adsorption was analized by using Atomic Absorption Spectroscopy (AAS). The result shows that in general, the increase of chemical concentration cause the increase of pore number of activated carbon due to an excessive chemical attack and lead the increase of adsorption. However it tend to decrease as further increasing in chemical activator concentration due to carbon collapsing. In general, the adsorption of Cu and Fe metal from wastewater by activated carbon increased as the activator concentration was increased.

  12. Byrsonima crassa Niedenzu (IK: antimicrobial activity and chemical study

    Directory of Open Access Journals (Sweden)

    W. Vilegas

    2009-01-01

    Full Text Available

    The methanolic extract of leaves from Byrsonima crassa, a Brazilian medicinal plant, was analyzed by CC and HPLC. Four constituents were isolated and identified as quercetin, methyl gallate, (--epigallocatechin gallate and quercetin-3-O-(2”-galloyl-a-L-arabinopyranoside. The methanolic and hydromethanolic extract, as well as fractions, were evaluated regarding their possible antimicrobial activity using in vitro methods. Results showed that both extracts and fractions exhibited significant antimicrobial activity against all tested strains. Keywords: Byrsonima crassa, antimicrobial activity, Malpighiaceae.

  13. Chemical bond activation observed with an x-ray laser

    International Nuclear Information System (INIS)

    Beye, Martin; Öberg, Henrik; Xin, Hongliang

    2016-01-01

    The concept of bonding and anti-bonding orbitals is fundamental in chemistry. The population of those orbitals and the energetic difference between the two reflect the strength of the bonding interaction. Weakening the bond is expected to reduce this energetic splitting, but the transient character of bond-activation has so far prohibited direct experimental access. Lastly, we apply time-resolved soft X-ray spectroscopy at a free-electron laser to directly observe the decreased bonding–anti-bonding splitting following bond-activation using an ultra short optical laser pulse.

  14. Anti-inflammation activity and chemical composition of flower ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-10-19

    Oct 19, 2009 ... inflammatory activity in vivo (carrageenan-induced hind paw edema in rats). The oil (100 ... pharmacological properties of H. coronarium flowers essential .... reaction with K3[Fe(CN)6], under formation of the colored complex ...

  15. A quantum chemical explanation of the antioxidant activity af flavonoids.

    NARCIS (Netherlands)

    van Acker, S.A.B.E.; de Groot, M.J.; van den Berg, D.J.; Tromp, M.N.J.L.; Donné-Op den Kelder, G.M.; van der Vijgh, W.J.F.; Bast, A.

    1996-01-01

    Flavonoids are a group of naturally occurring antioxidants, which over the past years have gained tremendous interest because of their possible therapeutic applicability. The mechanism of their antioxidant activity has been extensively studied over several decades. However, there is still much

  16. Incorporating Nondrug Social & Recreational Activities in Outpatient Chemical Dependency Treatment

    Science.gov (United States)

    Siporin, Sheldon; Baron, Lisa

    2012-01-01

    "Contingency Management programs (CMP) and non-drug social and recreational activities (NDSRA) are interventions premised on behavior theory that rely on external sources of reinforcement alternative to drug-based forms to decrease drug use. CMP usually employs vouchers as reinforcement for negative toxicologies. Despite research support, CMP…

  17. A Review on Chemical Constituents and Biological Activities of the ...

    African Journals Online (AJOL)

    The current review is aimed to deliver some updates on the ethnobotany, phytochemistry and biological activities of Beilschmiedia species in order to throw more light on their therapeutic potentials and future research priorities. Phytochemical studies on Beilschmiedia genus yielded essential oils, endiandric acid ...

  18. chemical composition and antimicrobial activity of the essential oil

    African Journals Online (AJOL)

    Hydro-distilled essential oil from Satureja biflora (Lamiaceae) growing in Kenya was analysed by gas chromatography mass spectrometry (GC-MS) and also evaluated for antimicrobial activity. Twenty two compounds which constitute 99.29 % of the total oil were identified. The oil was dominated by monoterpenes, which ...

  19. Chemical composition and toxic activity of essential oil of ...

    African Journals Online (AJOL)

    During our screening program for new agrochemicals from Chinese medicinal herbs, essential oil of Caryopteris incana aerial parts was found to possess strong insecticidal activities against the maize weevil, Sitophilus zeamais. A total of 37 components of the essential oil were identified by GC and GC/MS. Estragole ...

  20. chemical constituents and biological activity of three tanzanian wild

    African Journals Online (AJOL)

    Mgina

    antimicrobial activities infer that the three mushroom species are potential functional food substrates. INTRODUCTION. Termitomyces is a tropical edible ... extract (32 g) on cooling in the fridge at -. 4°C formed white crystals of mannitol and ... against the bacteria Vibrio cholerae and. Escherichia coli, and the fungus Candida.

  1. Essential oil from Artemisia phaeolepis: chemical composition and antimicrobial activities.

    Science.gov (United States)

    Ben Hsouna, Anis; Ben Halima, Nihed; Abdelkafi, Slim; Hamdi, Naceur

    2013-01-01

    Artemisia phaeolepis, a perennial herb with a strong volatile odor, grows on the grasslands of Mediterranean region. Essential oil obtained from Artemisia phaeolepis was analyzed by gas chromatography-flame ionization detection and gas chromatography-mass spectrometry. A total of 79 components representing 98.19% of the total oil were identified, and the main compounds in the oil were found to be eucalyptol (11.30%), camphor (8.21%), terpine-4-ol (7.32%), germacrene D (6.39), caryophyllene oxide (6.34%), and caryophyllene (5.37%). The essential oil showed definite inhibitory activity against 10 strains of test microorganisms. Eucalyptol, camphor, terpine-4-ol, caryophyllene, germacrene D and caryophyllene oxide were also examined as the major components of the oil. Camphor showed the strongest antimicrobial activity; terpine-4-ol, eucalyptol, caryophyllene and germacrene D were moderately active and caryophyllene oxide was weakly active. The study revealed that the antimicrobial properties of the essential oil can be attributed to the synergistic effects of its diverse major and minor components.

  2. Optimization of lead (ii) ions adsorption on to chemically activated ...

    African Journals Online (AJOL)

    The derivative thermal analysis (DTA) and thermogravimetric analysis (TGA) profile of the activated carbon were employed in the proximate analysis. The BET surface area shows a high microporous surface area and micropore volume of 840.38 m2/g and 0.30 cc/g respectively which aids sorption efficiency. The adsorption ...

  3. Chemical constituents of Cordia latifolia and their nematicidal activity.

    Science.gov (United States)

    Begum, Sabira; Perwaiz, Sobiya; Siddiqui, Bina S; Khan, Shazia; Fayyaz, Shahina; Ramzan, Musarrat

    2011-05-01

    Following nematicidal activity-guided isolation studies on the fruits, bark, and leaves of Cordia latifolia, two new constituents, cordinoic acid (=11-oxours-12-ene-23,28-dioic acid; 1) and cordicilin (=2-{[(E)-3-(3,4-dihydroxyphenyl)prop-2-enoyl]oxy}-3-[4-hydroxy-3-(stearoyloxy)phenyl]propanoic acid; 2) were isolated from the stem and leaves, respectively, together with nine known compounds, namely cordioic and cordifolic acid from the stem bark, latifolicin A-D and rosmarinic acid from the fruits, and cordinol and cordicinol from the leaves. Their structures were determined by means of spectroscopic analyses including 1D- and 2D-NMR techniques. The nematicidal activities of these constituents were determined against the root-knot nematode Meloidogyne incognita. Hundred percent mortality was caused by all of these after 72 h at a 0.125% concentration. Compound 1 and cordioic acid were most active and caused 100% mortality after 24 h at a 0.50% concentration. Furthermore, compound 2, the ester of rosemarinic acid, was found to be more active than the free acid. Copyright © 2011 Verlag Helvetica Chimica Acta AG, Zürich.

  4. Chemical composition and in vitro antioxidant activities of ...

    African Journals Online (AJOL)

    ... and the results were compared to the reference BHT (butyl hydroxy toluene). In the three earlier mentioned assays, the essential oil demonstrated a potential antioxidant which may be considered as potent agent in food preservation and drug discovery. Key words: Thymelaea hirsuta, essential oil, antioxidant activities.

  5. Essential oil of Algerian Eucalyptus citriodora: Chemical composition, antifungal activity.

    Science.gov (United States)

    Tolba, H; Moghrani, H; Benelmouffok, A; Kellou, D; Maachi, R

    2015-12-01

    Essential oil of Eucalyptus citriodora is a natural product which has been attributed for various medicinal uses. In the present investigation, E. citriodora essential oil was used to evaluate its antifungal effect against medically important dermatophytes. Essential oil from the Algerian E. citriodora leaves was analyzed by GC and GC/MS. The antifungal effect of E. citriodora essential oil was evaluated against four dermatophytes: Microsporum canis, Microsporum gypseum, Trichophyton mentagrophytes, Trichophyton rubrum using disc diffusion method, disc volatilization method, and agar dilution method. The chemical composition of the oil revealed the presence of 22 compounds accounting for 95.27% of the oil. The dominant compounds were citronellal (69.77%), citronellol (10.63%) and isopulegol (4.66%). The disc diffusion method, MIC and MFC determination, indicated that E. citriodora essential oil had a higher antifungal potential against the tested strains with inhibition zone diameter which varied from (12 to 90mm) and MIC and MFC values ranged from (0.6 to 5μL/mL and 1.25 to 5μL/mL) respectively. The M. gypseum was the most resistant to the oil. The results of the present study indicated that E. citriodora essential oil may be used as a new antifungal agent recommended by the pharmaceutical industries. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  6. Textural and chemical characterization of activated carbon prepared from shell of african palm (Elaeis guineensis by chemical activation with CaCl2 and MgCl2

    Directory of Open Access Journals (Sweden)

    Sergio Acevedo

    2015-09-01

    Full Text Available Activated carbons through chemical activation of African palm shells (Elaeis guineensis with magnesium chloride and calcium chloride solutions at different concentrations were obtained. The prepared materials were characterized textural and chemically. The results show that activated carbons with higher values of surface area and pore volume are obtained when solutions with lower concentrations of the activating agent are used. The obtained activated carbons have surface areas and pore volumes with values between 10 and 501 m2 /g and 0.01 and 0.29 cm3 /g respectively. Immersion enthalpies values of solids in water were between -14.3 and -32.8 J/g and benzene between -13.9 and -38.6 J/g. Total acidity and basicity of the activated carbons had values between 23 and 262 μmol/g 123 and 1724 μmol/g respectively. pH at the point of zero charge was also determined with values between 4.08 and 9.92 for set of activated carbons . The results show that activation with CaCl2 and MgCl2 salts produce activated carbons with pores in the range of mesopores for facilitate entry of the adsorbate into the materials.

  7. Development of a New Decision Tree to Rapidly Screen Chemical Estrogenic Activities of Xenopus laevis.

    Science.gov (United States)

    Wang, Ting; Li, Weiying; Zheng, Xiaofeng; Lin, Zhifen; Kong, Deyang

    2014-02-01

    During the last past decades, there is an increasing number of studies about estrogenic activities of the environmental pollutants on amphibians and many determination methods have been proposed. However, these determination methods are time-consuming and expensive, and a rapid and simple method to screen and test the chemicals for estrogenic activities to amphibians is therefore imperative. Herein is proposed a new decision tree formulated not only with physicochemical parameters but also a biological parameter that was successfully used to screen estrogenic activities of the chemicals on amphibians. The biological parameter, CDOCKER interaction energy (Ebinding ) between chemicals and the target proteins was calculated based on the method of molecular docking, and it was used to revise the decision tree formulated by Hong only with physicochemical parameters for screening estrogenic activity of chemicals in rat. According to the correlation between Ebinding of rat and Xenopus laevis, a new decision tree for estrogenic activities in Xenopus laevis is finally proposed. Then it was validated by using the randomly 8 chemicals which can be frequently exposed to Xenopus laevis, and the agreement between the results from the new decision tree and the ones from experiments is generally satisfactory. Consequently, the new decision tree can be used to screen the estrogenic activities of the chemicals, and combinational use of the Ebinding and classical physicochemical parameters can greatly improves Hong's decision tree. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Co-conditioning and dewatering of chemical sludge and waste activated sludge.

    Science.gov (United States)

    Chang, G R; Liu, J C; Lee, D J

    2001-03-01

    The conditioning and dewatering behaviors of chemical and waste activated sludges from a tannery were studied. Capillary suction time (CST), specific resistance to filtration (SRF), and bound water content were used to evaluate the sludge dewatering behaviors. Zeta potentials were also measured. Experiments were conducted on each sludge conditioned and dewatered separately, and on the sludge mixed at various ratios. Results indicate that the chemical sludge was relatively difficult to be dewatered, even in the presence of polyelectrolyte. When the waste activated sludge was mixed with the chemical sludge at ratios of 1:1 and 2:1, respectively, the dewaterability of chemical sludge improved remarkably while the relatively better dewaterability of the waste activated sludge deteriorated only to a limited extent. As the mixing ratios became 4:1 and 8:1, the dewaterability of the mixed sludge was equal to that of the waste activated sludge. The optimal polyelectrolyte dosage for the mixed sludge was equal to or less than that of the waste activated sludge. It is proposed that the chemical sludges act as skeleton builders that reduce the compressibility of the mixed sludge whose dewaterability is enhanced. Bound water contents of sludge decreased at low polyelectrolyte dosage and were not significantly affected as polyelectrolyte dosage increased. Advantages and disadvantages of co-conditioning and dewatering chemical sludge and waste activated sludge were discussed.

  9. Hangman Catalysis for Photo- and Photoelectro- Chemical Activation of Water

    Energy Technology Data Exchange (ETDEWEB)

    Nocera, Daniel

    2014-04-15

    The focus of this DOE program is solar fuels – specifically the chemistry for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) from water and the oxygen reduction reaction (ORR) to water These three reactions are at the heart of renewable energy conversion. The bond-making and bond-breaking chemistry that underpins these transformations is not well understood. We are developing insight into such chemistry by creating a series of ligand constructs that poise an acid-base functionality over a redox active metal platform. These “hangman” ligands utilize the acid-base functionality to form a secondary coordination sphere that can assist proton movement and facilitate substrate assembly and activation within the molecular cleft. The grant period funding cycle focused on synthesis and reactivity of hangman porphyrins and corroles for HER, OER and ORR.

  10. Facile Chemical Access to Biologically Active Norcantharidin Derivatives from Biomass

    Directory of Open Access Journals (Sweden)

    Konstantin I. Galkin

    2017-12-01

    Full Text Available Reductive amination of 2,5-diformylfuran (DFF was used to implement the transition from bio-derived 5-hydroxymethylfurfural (HMF to pharmaceuticals. The synthesized bis(aminomethylfurans were utilized as building blocks for the construction of new derivatives with structural cores of naturally occurring biologically active compounds. Using the one-pot procedure, which included the Diels–Alder reaction followed by hydrogenation of the double bond, bio-derived analogues of the anticancer drug norcantharidin were obtained. The cyclization process was diastereoselective, and resulted in the formation of tricyclic products with the endo configuration. Analysis of cytotoxycity for the resulting tricyclic amine-containing compounds showed an increase of anticancer activity as compared with the unsubstituted norcantharimide.

  11. Chemical study and antifouling activity of Caribbean octocoral Eunicea laciniata

    International Nuclear Information System (INIS)

    Cuadrado Silva, Carmen Tatiana; Castellanos Hernandez, Leonardo; Osorno Reyes, Oscar Eduardo; Ramos Rodriguez, Freddy Alejandro; Duque Beltran, Carmenza

    2010-01-01

    The bioassay guided purification of the octocoral Eunicea laciniata organic extract, collected at Santa Marta bay, Colombia, allowed the isolation of the new compound (-)-3β-pregna-5,20-dienyl-β-D-arabinopyranoside (1), along with the known compounds 1(S * ),11(R * )-dolabell-3(E),7(E),12(18)-triene (2), 13-keto-1(S),11(R)-dolabell-3(E),7(E),12(18)-triene (3), cholest- 5,22-dien-3β-ol (4), cholesterol (5), y brassicasterol (6). The structure and absolute configuration of 1 was determined on based spectroscopic analyses (NMR and CD). The extract showed antifouling activity against five strains of marine bacteria associated to heavy fouled surfaces. Also showed activity against the cypris of the cosmopolitan barnacle Balanus amphitrite, and low toxicity in Artemia salina test. (author)

  12. Chemical Composition, Antifungal and Insecticidal Activities of Hedychium Essential Oils

    Science.gov (United States)

    2013-04-11

    Hedychiums have been reported to possess antibacterial, antifungal, and insecticidal activities [4,5]. Strawberry anthracnose, caused by the plant...pathogens Colletotrichum species is one of the most important diseases affecting strawberries worldwide [6]. Colletotrichum fragariae Brooks is most...often associated with anthracnose crown rot of strawberries grown in hot, humid areas such as the southeastern United States [7]. The azalea lace bug

  13. Antidiabetic Activity and Chemical Composition of Sanbai Melon Seed Oil

    Science.gov (United States)

    Li, Haili; Zhao, Hang; Zhang, Ya; Qiu, Pengcheng; Li, Jie

    2018-01-01

    Objectives Many fruits and herbs had been used in Traditional Chinese Medicines for treating diabetes mellitus (DM); however, scientific and accurate evidences regarding their efficacy and possible mechanisms were largely unknown. Sanbai melon seed oil (SMSO) was used in folk medicine in treating DM, but there is no literature about these effects. The present study was aimed at confirming the treatment effects of SMSO in type 1 DM. Methods Diabetes was induced by single intraperitoneal injection of streptozotocin (STZ) at a dose of 65 mg/kg body weight. After diabetes induction, mice were treated with SMSO at dose of 1 g/kg, 2 g/kg, and 4 g/kg. Drugs were given by gavage administration once a day continuously for 28 days. At the end of treatment, several biochemical parameters and molecular mechanisms were determined by biochemical assays, ELISA, and Western blotting. The chemical compositions of SMSO were also tested. Results SMSO treatment significantly improved the symptoms of weight loss, polydipsia, reduced FBG level, increased plasma insulin levels, reduced plasma lipids levels, and protected islet injury. The results also showed that SMSO mitigated oxidative stress and alleviated the liver and renal injury in diabetes mice. SMSO also protected islet cells from apoptotic damage by suppressing ER mediated and mitochondrial dependent apoptotic pathways. Further constituent analysis results showed that SMSO had rich natural resources which had beneficial effects on DM. Conclusions This study showed that SMSO had excellent antidiabetes effect and provided scientific basis for the use of SMSO as the functional ingredients production and dietary supplements production in the food and pharmaceutical industries. PMID:29853958

  14. Antiproliferative Activity and Chemical Constituents of Hypericum dyeri. Rehder

    International Nuclear Information System (INIS)

    Ali, M.; Arfan, M.; Zaman, K.

    2013-01-01

    The antiproliferative activity of hexane (F1), ethyl acetate (F2), butanol (F3) and water (F4) extracts of Hypericum dyeri were tested in vitro for their anti- proliferative (anticancer) activity on the cell lines: HT-29 human colon adenocarcinoma, NCI-H460 human non-small cell lung carcinoma, MCF-7 human breast cancer, OVCAR-3 human ovarian adenocarcinoma and RXF-393 human renal cell carcinoma with etoposide as positive control. Among the various extracts the F1 showed relatively potent anti-proliferative activity (IC50, 17.20 +- 4.80 micro g/mL) on NCI-H460 human non-small cell lung carcinoma cell growth. Six compounds were also isolated for the first time from this source. These phytochemicals were identified as 1-Octatriacontanol (1), Hexacosyl tetracosanoate (2), Geddic acid (3), Octacosanoic acid (4), Ceric acid (5) and Sitosterol (6) on the basis of spectroscopic studies such as 1H NMR ,13C NMR, 2D NMR and Mass spectroscopy as well as established with help of reported literature. (author)

  15. Evaluation of Biological Activities of Chemically Synthesized Silver Nanoparticles

    International Nuclear Information System (INIS)

    Mostafa, A. A.; Solkamy, E.N.; Sayed, Sh. R. M.; Khan, M.; Shaik, M.R.; Al-Warthan, A.; Adil, S.F.

    2015-01-01

    Silver nanoparticles were synthesized by the earlier reported methods. The synthesized nanoparticles were characterized using ultraviolet-visible spectrophotometry (UV/Vis), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX), and X-ray powder diffraction (XRD). The synthesized materials were also evaluated for their antibacterial activity against Gram positive and Gram negative bacterial strains. TEM micrograph showed the spherical morphology of AgNPs with size range of 40-60 nm. The synthesized nanoparticles showed a strong antimicrobial activity and their effect depends upon bacterial strain as AgNPs exhibited greater inhibition zone for Pseudomonas aeruginosa (19.1 mm) followed by Staphylococcus aureus (14.8?mm) and S. pyogenes (13.6 mm) while the least activity was observed for Salmonella typhi (12.5 mm) at concentration of 5 μg/disc. The minimum inhibitory concentration (MIC) of AgNPs against S. aureus was 2.5 μg/disc and less than 2.5 μg/disc for P. aeruginosa. These results suggested that AgNPs can be used as an effective antiseptic agent for infectious control in medical field.

  16. Chemical Characterization, Antioxidant and Enzymatic Activity of Brines from Scandinavian Marinated Herring Products

    DEFF Research Database (Denmark)

    Gringer, Nina; Osman, Ali; Nielsen, Henrik Hauch

    2014-01-01

    Brines generated during the last marination step in the production of marinated herring (Clupea harengus) were chemically characterized and analyzed for antioxidant and enzyme activities. The end-products were vinegar cured, spice cured and traditional barrel-salted herring with either salt...... or spices. The chemical characterization encompassed pH, dry matter, ash, salt, fatty acids, protein, polypeptide pattern, iron and nitrogen. The antioxidant activity was tested with three assays measuring: iron chelation, reducing power and radical scavenging activity. The enzymatic activity for peroxidase...

  17. Pinostrobin Derivatives from PrenylationReaction and their Antibacterial Activity against Clinical Bacteria

    Science.gov (United States)

    Marliyana, S. D.; Mujahidin, D.; Syah, Y. M.

    2018-04-01

    Kaempferia pandurata (syn. Boesenbergia rotunda, B. pandurata (Roxb.)Schltr), locally known as "TemuKunci"in Indonesia, is one of the medicinal plants of the family Zingiberaceae. Phytochemical studies on the rhizome of K. pandurata showed the presence of flavonoid derivative, namely flavanones, which constitute as the main components of this plant. Bioactivity studies on this species exhibited various biological activities, such as antibacteria, anti-inflammatory, antitumor, antidiarrhea, antidisentri, anti-HIV, antioxidant, antipyretic, analgesic and insecticides. Among the biological activities, the antibacterial activity results are important as an attempt to answer the emergence of resistance of some bacteria against existing drugs, as well as the emergence of a number of outbreaks of disease caused by bacteria. Therefore, a search to find new compounds that are potential as an antibacterial is an urgent matter. The present study was aimed at the chemical transformation of pinostrobin (1) from K. pandurata rhizome and an antibacterial activity.The chemical transformation was performed through a prenylation reaction of pinostrobin (1) which is the main component of K. pandurata rhizome. The prenylation reaction was carried out by reacting pinostrobin (1) with prenyl bromide and potassium carbonat (K2CO3). The purification of product was done using the radial chromatography with mix solvent n-hexane and ethyl acetate (97.5:2.5; 9.5:0.5; 9.0:1.0.; 8.0:2.0). The purity test of isolated compound was analysedby TLC using different types of eluent. The identification of compounds was determined based on NMR data and mass spectra analysis. Five compounds were obtained from the prenylation reaction, i.e. monooxyprenylated pinostrobin (2), monooxyprenylated chalcone (3), diprenylated chalcone (4), triprenylated chalcone (5), and triprenylated cyclohexene chalcone (6). These compounds were tested for antibacterial activities against four clinical bacteria, namely

  18. Immune activation affects chemical sexual ornaments of male Iberian wall lizards

    Science.gov (United States)

    López, Pilar; Gabirot, Marianne; Martín, José

    2009-01-01

    Many animals use chemical signals in sexual selection, but it is not clear how these sexual traits might have evolved to signal honestly male condition. It is possible that there is a trade-off between maintaining the immune system and the elaboration of ornaments. We experimentally challenged the immune system of male Iberian wall lizards, Podarcis hispanica, with a bacterial antigen (lipopolysaccharide), without pathogenic effects, to explore whether the immune activation affected chemical ornaments. Immune activation resulted in decreased proportions of a major chemical in femoral secretions (cholesta-5,7-dien-3-ol = provitamin D3) known to be selected in scent of males by females and which active form (vitamin D) has a variety of important effects on immune system function. This result suggests the existence of a potential trade-off between physiological regulation of the immune system and the allocation of essential nutrients (vitamins) to sexual chemical ornaments in male lizards.

  19. Neutron activation analysis of high-purity iron in comparison with chemical analysis

    International Nuclear Information System (INIS)

    Kinomura, Atsushi; Horino, Yuji; Takaki, Seiichi; Abiko, Kenji

    2000-01-01

    Neutron activation analysis of iron samples of three different purity levels has been performed and compared with chemical analysis for 30 metallic and metalloid impurity elements. The concentration of As, Cl, Cu, Sb and V detected by neutron activation analysis was mostly in agreement with that obtained by chemical analysis. The sensitivity limits of neutron activation analysis of three kinds of iron samples were calculated and found to be reasonable compared with measured values or detection limits of chemical analysis; however, most of them were above the detection limits of chemical analysis. Graphite-shielded irradiation to suppress fast neutron reactions was effective for Mn analysis without decreasing sensitivity to the other impurity elements. (author)

  20. Pronuclear formation by ICSI using chemically activated ovine oocytes and zona pellucida bound sperm

    Directory of Open Access Journals (Sweden)

    J. E. Hernández-Pichardo

    2016-11-01

    Full Text Available Abstract Background In order to improve ICSI, appropiate sperm selection and oocyte activation is necessary. The objective of the present study was to determine the efficiency of fertilization using ICSI with chemically activated ovine oocytes and sperm selected by swim up (SU or swim up + zona pellucida (SU + ZP binding. Results Experiment 1, 4–20 replicates with total 821 in vitro matured oocytes were chemically activated with ethanol, calcium ionophore or ionomycin, to determine oocyte activation (precense of one PN. Treatments showed similar results (54, 47, 42 %, respectively but statistically differents (P  0.05. Conclusions Chemical activation induces higher ovine oocyte activation than mechanical activation. Ethanol slightly displays higher oocyte activation than calcium ionophore and ionomicine. Sperm selection with SU + ZP increased AR/A and AR/D rates in comparison with SU in fresh and frozen-thawed sperm. According to this, in terms of fertilization rates, chemical activation after ICSI increased oocyte PN formation compared to mechanical activation. Also, fresh sperm treated with SU and SU + ZP were significantly different than frozen-thawed sperm, but between sperm treatments no significant differences were obtained.

  1. Antioxidant Activity of Chemical Constituents Isolated from Pithecellobium clypearia

    Directory of Open Access Journals (Sweden)

    Lingzhi Li

    2015-04-01

    Full Text Available Phytochemical investigation of the aqueous extract of Pithecellobium clypearia afforded one n ovel compound, clypearoside A(1, and one new stereoisomer , (--(2S,3S-epigallocatechin-7-gallate(2 and four known ones (3-6. Their structures were elucidated on the basis of spectroscopic data, especially 2D NMR, HRESIMS and ECD spectra. Compounds 2-4 showed strong activity against DPPH (diphenylpicrylhydrazyl and ABTS (2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonate with an IC 50 value of 11.9-13.2 μg/mL (DPPH and 4.5-6.4 μg/mL (ABTS.

  2. Phyto chemical and bio activities research on Tinospora crispa (Patawali)

    International Nuclear Information System (INIS)

    Shakirah Abdul Shukor

    2010-01-01

    The usage of traditional therapeutic medicine is gaining attention as consumption to modern therapeutic medicine can affect health and also causing death. Because of this resurgence of interest, the research on medicinal plant is growing phenomenally in Malaysia as Tinospora crispa is one of the potential candidates and this plant is been use since long time ago as medicine. Solvent extraction method run on Tinospora crispa's stem had resulted 5 extracts which were hexane, chloroform, butanol, aqueous and methanol. Phyto chemical screening of hexane extract showed existence of alkaloid, flavonon, polyphenol substances and steroid type saponins. Chloroform extract consists alkaloid and triterpenoid type saponins while alkaloid, flavon and polyphenol substances found in butanol extract. Aqueous extract consist free acid and steroid type saponins whereas alkaloid, tannin and triterpenoid type saponins were found in methanol extract. Hexane, chloroform, and butanol extracts shows inhibition zone for bacteria gram-positive, Staphylococcus aureus where each extracts give inhibitory zone diameter of 1.5 cm, 1.3 cm, and 1.2 cm. There is no inhibitory zone for methanol and aqueous extract. As observation for bacteria gram-negative, Escherichia coli shows negative result for inhibitory zone. The LC50 acute for hexane, chloroform, butanol, aqueous and methanol extracts are 3162.28 ppm, 7813.71 ppm, 380.72 ppm, 662.87 ppm, dan 1847.85 ppm respectively. LC50 chronic for hexane, chloroform, butanol, aqueous and methanol extracts are 273.84 ppm, 259.29 ppm, 17.78 ppm, 12.02 ppm, dan 15.44 ppm respectively. Butanol, aqueous and methanol extracts gives higher relative toxicity compared to potassium dichromate. Overall, Tinospora crispas extracts are toxic compared with relative toxicity of potassium dichromate. The solvent system of toulene, acetone and chloroform with the proportion of 8: 2: 5 for hexane extract indicated 9 substances where chloroform extract yielded 6 substance

  3. [Chemical constituents of Jasminum giraldii and their antioxidant activity].

    Science.gov (United States)

    Zhang, Xiu-Peng; Qin, Hui; Yang, Fang; Chai, Jiang; Wang, Xin; Song, Xiao-Mei; Mei, Qi-Bing; Feng, Feng; Yue, Zheng-Gang

    2014-06-01

    Ten compounds were isolated from the barks of Jasminum giraldii by means of various of chromatographic techniques such as silica gel, Sephadex LH-20 and Rp-HPLC. Their structures were identified by spectroscopic data analysis as (+)-medioresinol (1), (+) -syringaresinol (2), syringaresinol-4'-O-beta-D-glucopyranoside (3), oleanic acid (4), 3-methoxy-4-hydroxy-trans-cinnamaldehyde (5), trans-sinapaldehyde (6), syringaldehyde (7), 1-(4-methoxy -phenyl) -ethanol (8), trans-cinnamic acid (9), and 4-(1-methoxyethyl) -phenol (10). Among them, compounds 1-3, 5-8 and 10 were isolated from the J. genus for the first time and compounds 4 and 9 were obtained from J. giraldii for the first time. In the DPPH free radical scavenging assay, compound 1 exhibited significant activity (IC50 55.1 micromol x L(-1)), compared with vitamin C(IC50 59.9 micromol x L(-1)); and compound 2 showed moderate activity (IC50 79.0 micromol x L(-1)), compared with 2, 6-di-tert-butyl4-methylphenol (IC50 236 micromol x L(-1)).

  4. Chemical constituents and antioxidant activity of Byrsonima gardneriana (Malpighiaceae)

    International Nuclear Information System (INIS)

    Rolim, Thaisa Leite; Wanderley, Flavia Talita de Sousa; Cunha, Emidio Vasconcelos Leitao da; Tavares, Josean Fechine; Oliveira, Adriana Maria Fernandes de; Assis, Temilce Simoes

    2013-01-01

    The phytochemical investigation of Byrsonima gardneriana led to the isolation of five triterpenes and one flavonoid: D:B-Friedoolean-5-en-3-one (1), friedoolean-14-en-3-one (2), friedelan-3-one (3), lup-20(29)-en-3-ol (4), 3β-hydroxiolean-12-ene (5) and 3,3',4',5,7-pentahydroxyflavan (6). Their structures were assigned based on spectroscopic analyses, including two-dimensional NMR techniques and comparison with published spectral data. Antioxidant activities of ethanol extract and phases were measured using the 1,2-diphenyl- 2-picryl-hydrazyl (DPPH) free radical scavenging assay, evaluation of total phenolic content and trolox equivalent antioxidant capacity (TEAC). (author)

  5. Chemical Constituents and Antifungal Activity of Ficus hirta Vahl. Fruits

    Directory of Open Access Journals (Sweden)

    Chunpeng Wan

    2017-09-01

    Full Text Available Phytochemical investigation of Ficus hirta Vahl. (Moraceae fruits led to isolate two carboline alkaloids (1 and 2, five sesquiterpenoids/norsesquiterpenoids (3–7, three flavonoids (8–10, and one phenylpropane-1,2-diol (11. Their structures were elucidated by the analysis of their 1D and 2D NMR, and HR-ESI-MS data. All of the isolates were isolated from this species for the first time, while compounds 2, 4–6, and 8–11 were firstly reported from the genus Ficus. Antifungal assay revealed that compound 8 (namely pinocembrin-7-O-β-d-glucoside, a major flavonoid compound present in the ethanol extract of F. hirta fruits, showed good antifungal activity against Penicillium italicum, the phytopathogen of citrus blue mold caused the majority rotten of citrus fruits.

  6. Antihepatotoxic activity and chemical constituents of Buddleja asiatica Lour.

    Science.gov (United States)

    El-Domiaty, Maher M; Wink, Michael; Abdel Aal, Mahmoud M; Abou-Hashem, Maged M; Abd-Alla, Rehab H

    2009-01-01

    A new natural compound, named 6-O-(3",4"-dimethoxycinnamoyl) catalpol, was isolated from the defatted alcoholic extract of the flowering parts of Buddleja asiatica Lour. (family Scrophulariaceae). Other separated known compounds included steroids (beta-sitosterol, stigmasterol, stigmasterol-O-glucoside, beta-sitosterol-O-glucoside), iridoid glucosides (methyl catalpol, catalpol, aucubin), phenylpropanoids (isoacteoside and acteoside), a triterpene saponin (mimengoside A), flavonoids (diosmin and linarin) in addition to the free sugars mannitol and sucrose. The structures of the isolated compounds were established by 1H and 13C NMR and mass spectrometry. Furthermore, the polar fraction of the flowering parts and the roots showed substantial antihepatotoxic activity comparable to that of the lignan silymarin.

  7. Fungal phytotoxins with potential herbicidal activity: chemical and biological characterization.

    Science.gov (United States)

    Cimmino, Alessio; Masi, Marco; Evidente, Marco; Superchi, Stefano; Evidente, Antonio

    2015-12-19

    Covering: 2007 to 2015 Fungal phytotoxins are secondary metabolites playing an important role in the induction of disease symptoms interfering with host plant physiological processes. Although fungal pathogens represent a heavy constraint for agrarian production and for forest and environmental heritage, they can also represent an ecofriendly alternative to manage weeds. Indeed, the phytotoxins produced by weed pathogenic fungi are an efficient tool to design natural, safe bioherbicides. Their use could avoid that of synthetic pesticides causing resistance in the host plants and the long term impact of residues in agricultural products with a risk to human and animal health. The isolation and structural and biological characterization of phytotoxins produced by pathogenic fungi for weeds, including parasitic plants, are described. Structure activity relationships and mode of action studies for some phytotoxins are also reported to elucidate the herbicide potential of these promising fungal metabolites.

  8. Influence of chemical agents on the surface area and porosity of active carbon hollow fibers

    Directory of Open Access Journals (Sweden)

    LJILJANA M. KLJAJEVIĆ

    2011-09-01

    Full Text Available Active carbon hollow fibers were prepared from regenerated polysulfone hollow fibers by chemical activation using: disodium hydrogen phosphate 2-hydrate, disodium tetraborate 10-hydrate, hydrogen peroxide, and diammonium hydrogen phosphate. After chemical activation fibers were carbonized in an inert atmosphere. The specific surface area and porosity of obtained carbons were studied by nitrogen adsorption–desorption isotherms at 77 K, while the structures were examined with scanning electron microscopy and X-ray diffraction. The activation process increases these adsorption properties of fibers being more pronounced for active carbon fibers obtained with disodium tetraborate 10-hydrate and hydrogen peroxide as activator. The obtained active hollow carbons are microporous with different pore size distribution. Chemical activation with phosphates produces active carbon material with small surface area but with both mesopores and micropores. X-ray diffraction shows that besides turbostratic structure typical for carbon materials, there are some peaks which indicate some intermediate reaction products when sodium salts were used as activating agent. Based on data from the electrochemical measurements the activity and porosity of the active fibers depend strongly on the oxidizing agent applied.

  9. Polysaccharides from Arctium lappa L.: Chemical structure and biological activity.

    Science.gov (United States)

    Carlotto, Juliane; de Souza, Lauro M; Baggio, Cristiane H; Werner, Maria Fernanda de P; Maria-Ferreira, Daniele; Sassaki, Guilherme L; Iacomini, Marcello; Cipriani, Thales R

    2016-10-01

    The plant Arctium lappa L. is popularly used to relieve symptoms of inflammatory disorders. A crude polysaccharide fraction (SAA) resulting of aqueous extraction of A. lappa leaves showed a dose dependent anti-edematogenic activity on carrageenan-induced paw edema, which persisted for up to 48h. Sequential fractionation by ultrafiltration at 50kDa and 30kDa cut-off membranes yielded three fractions, namely RF50, RF30, and EF30. All these maintained the anti-edematogenic effect, but RF30 showed a more potent action, inhibiting 57% of the paw edema at a dose of 4.9mg/kg. The polysaccharide RF30 contained galacturonic acid, galactose, arabinose, rhamnose, glucose, and mannose in a 7:4:2:1:2:1 ratio and had a Mw of 91,000g/mol. Methylation analysis and NMR spectroscopy indicated that RF30 is mainly constituted by a type I rhamnogalacturonan branched by side chains of types I and II arabinogalactans, and arabinan. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Influence of chemical sprinkle on the processes in activated tank of wastewater treatment

    Directory of Open Access Journals (Sweden)

    Milan Búgel

    2012-12-01

    Full Text Available The research deals with processes occurring in the activation tank during the snow-melt inflow of chemical component of roadsalt. Chemical composition of the suspension in the activation tank is changing following the metabolism of organisms and chemicalcomposition of the influent wastewater. Sludge and wastewater in nitrification tail of the activation tank has higher conductivity, highercontents of chloride, higher sludge index and other characteristics are changing during snow – melt. The amount of the inflow road saltis a determining factor of lyses of microorganism cells.

  11. Effect of textural and chemical characteristics of activated carbons on phenol adsorption in aqueous solutions

    Directory of Open Access Journals (Sweden)

    Vargas Diana P.

    2017-12-01

    Full Text Available The effect of textural and chemical properties such as: surface area, pore volume and chemical groups content of the granular activated carbon and monoliths on phenol adsorption in aqueous solutions was studied. Granular activated carbon and monolith samples were produced by chemical activation. They were characterized by using N2 adsorption at 77 K, CO2 adsorption at 273 K, Boehm Titrations and immersion calorimetry in phenol solutions. Microporous materials with different pore size distribution, surface area between 516 and 1685 m2 g−1 and pore volumes between 0.24 and 0.58 cm3 g−1 were obtained. Phenol adsorption capacity of the activated carbon materials increased with increasing BET surface area and pore volume, and is favored by their surface functional groups that act as electron donors. Phenol adsorption capacities are in ranged between 73.5 and 389.4 mg · g−1.

  12. Instrumental neutron activation analysis, a valuable link in chemical metrology

    International Nuclear Information System (INIS)

    Zeisler, R.; Lindstrom, R.M.; Greenberg, R.R.

    2002-01-01

    Instrumental neutron activation analysis (INAA) is sufficiently versatile to establish a direct link to the amount of substance determined. The inherent quality parameters of INAA, such as being virtually free of blank, having fully accountable effects of matrix and physical form, and operating over a huge range of amounts, allows the comparison of a mole (or its fraction) of a pure element with the amount of substance in the sample analyzed with the same direct relationship as a beam balance provides. Indeed, varieties of this approach are in common use in INAA in the comparator methods of quantitation. To eliminate possible perturbations of the traceability chain as they may occur in common INAA practice, experimental measurements have been set up that only involve the fraction of a mole of the element(s) of interest in form of the pure element, compound or certified standard and the unknown sample. This principle has been used in INAA measurements for certification value assignment of high temperature alloy SRMs. To further demonstrate the performance parameters of INAA, we selected the determination of chromium in SRM 1152a Stainless Steel by direct non-destructive comparison with the pure metal in form of crystalline chromium. The measurements were validated with weighed aliquots of SRM 3112a dried on filter paper pellets. The experimental results do not show deviations beyond the uncertainties of the SRMs (≤ 0.2 % relative), and the assessment of the uncertainty budget indicates that expanded uncertainties of ≤ 0.3 % are achievable. The measurements demonstrate that INAA can meet the CCQM definition of a primary ratio method of analysis

  13. Orientation of sustainable management of chemical company with international activity

    Directory of Open Access Journals (Sweden)

    Valéria da Veiga Dias

    2013-04-01

    Full Text Available The search for new business possibilities, either through international activities and capture niche markets appear as a distinct trend among organizations that target growth. For this growing number of organizations intent on investing in new issues related to values such as citizenship, ethics and environmental concerns. There is the adoption of a more responsive to the community or even the acceptance of responsibility for the impacts of their production processes, inserting themselves in what was initially called the Social Responsibility within the business context and developed the concept of Elkington (1998 generated a discussion about a new movement that was called a sustainable paradigm. It was observed generally that sustainable management is still very close to supporting tools and not as part of the construction of corporate strategy although it is possible to realize that they seek a greater involvement in this direction when they start to review their strategies. This question can be perceived at different levels between the companies, but which shows the issue is the lack of direct indicators for investment and sustainable return. Sustainable management proved to be a source of opportunity for overseas business for the companies studied, as preparation for work with environmental legislation, global requirements, raw materials and environmentally friendly processes organizations prepared to market in the global sphere, and Brazil note that the innovative products for their production process and / or alternative raw material still do not get the spotlight. Acting in a sustainable manner enables the development of strategies agreed with conscious posture and changes in cultural terms in general, which can create new opportunities for those who can keep up with the global business scenario.

  14. Chemical composition and antioxidant activity of certain Morus species

    Science.gov (United States)

    Imran, Mohammad; Khan, Hamayun; Shah, Mohibullah; Khan, Rasool; Khan, Faridullah

    2010-01-01

    In the present work, the fruits of four Morus species, namely Morus alba (white mulberry), Morus nigra (black mulberry), Morus laevigata (large white fruit), and Morus laevigata (large black fruit), were analyzed for proximate composition, essential minerals, and antioxidant potentials. For this purpose, the ripe fruits were collected from the northern regions of Pakistan. The major nutritional components (moisture, ash, lipids, proteins, fibres, carbohydrates, and total sugar) were found to be in the suitable range along with good computed energy. Total dry weight, pH, and titratable acidity (percent citric acid) were (17.60±1.94)–(21.97±2.34) mg/100 g, (3.20±0.07)–(4.78±0.15), and (0.84±0.40)%–(2.00±0.08)%, respectively. Low riboflavin (vitamin B2) and niacin (vitamin B3) contents were recorded in all the fruits, while ascorbic acid (vitamin C) was in the range from (15.20±1.25) to (17.03±1.71) mg/100 g fresh weight (FW). The mulberry fruits were rich with regard to the total phenol and alkaloid contents, having values of (880±7.20)–(1650±12.25) mg/100 g FW and (390±.22)–(660±5.25) mg/100 g FW, respectively. Sufficient quantities of essential macro-(K, Ca, Mg, and Na) and micro-(Fe, Zn, and Ni) elements were found in all the fruits. K was the predominant element with concentration ranging from (1270±9.36) to (1731±11.50) mg/100 g, while Ca, Na, and Mg contents were (440±3.21)–(576±7.37), (260±3.86)–(280±3.50), and (24±3.51)–(360±4.20) mg/100 g, respectivly. The decreasing order of micro-minerals was Fe>Zn>Ni. The radical scavenging activity of methanolic extract of fruits was concentration-dependent and showed a correlation with total phenolic constituents of the respective fruits. Based on the results obtained, mulberry fruits were found to serve as a potential source of food diet and natural antioxidants. PMID:21121077

  15. Chemical diversity and antileishmanial activity of crude extracts of Laurencia complex (Ceramiales, Rhodophyta from Brazil

    Directory of Open Access Journals (Sweden)

    Fernanda L. da S. Machado

    Full Text Available Chemical profiles of extracts of four species from Laurencia complex (Ceramiales, Rhodophyta from different populations collected along Southeast Brazilian coast were assessed by High Performance Liquid Chromatography coupled with a Diode Array Detector in order to observe geographic chemical variability. Aiming to evaluate the impact of chemical diversity on potential pharmaceutical uses, the extracts were tested against the promastigote form of Leishmania amazonensis. The most active extracts were submitted to anti-amastigote and cytotoxicity assays. Principal Component Analysis of the chromatograms resulted in four major groups of chemical profiles according to the presence of leishmanicidal chamigranes (--elatol and obtusol. The existence of chemotypes, displaying variable pharmacological action, is proposed for the differences observed in L. dendroidea samples. Although all extracts were found active against promastigote form of L. amazonensis, their efficacy was remarkably different and not related to the variation of (--elatol and obtusol, which indicates the presence of additional compounds with antileishmanial activity. Moreover, the active extracts also displayed anti-amastigote activity and none of them were considered cytotoxic. The results highlight that the knowledge of chemical geographic variability can be valuable in the search of new antileishmanial compounds from marine sources.

  16. Efficacy and safety of superficial chemical peeling in treatment of active acne vulgaris.

    Science.gov (United States)

    Al-Talib, Hassanain; Al-Khateeb, Alyaa; Hameed, Ayad; Murugaiah, Chandrika

    2017-01-01

    Acne vulgaris is an extremely common condition affecting the pilosebaceous unit of the skin and characterized by presence of comedones, papules, pustules, nodules, cysts, which might result in permanent scars. Acne vulgaris commonly involve adolescents and young age groups. Active acne vulgaris is usually associated with several complications like hyper or hypopigmentation, scar formation and skin disfigurement. Previous studies have targeted the efficiency and safety of local and systemic agents in the treatment of active acne vulgaris. Superficial chemical peeling is a skin-wounding procedure which might cause some potentially undesirable adverse events. This study was conducted to review the efficacy and safety of superficial chemical peeling in the treatment of active acne vulgaris. It is a structured review of an earlier seven articles meeting the inclusion and exclusion criteria. The clinical assessments were based on pretreatment and post-treatment comparisons and the role of superficial chemical peeling in reduction of papules, pustules and comedones in active acne vulgaris. This study showed that almost all patients tolerated well the chemical peeling procedures despite a mild discomfort, burning, irritation and erythema have been reported; also the incidence of major adverse events was very low and easily manageable. In conclusion, chemical peeling with glycolic acid is a well-tolerated and safe treatment modality in active acne vulgaris while salicylic acid peels is a more convenient for treatment of darker skin patients and it showed significant and earlier improvement than glycolic acid.

  17. Activity profiles of 309 ToxCastTM chemicals evaluated across 292 biochemical targets

    International Nuclear Information System (INIS)

    Knudsen, Thomas B.; Houck, Keith A.; Sipes, Nisha S.; Singh, Amar V.; Judson, Richard S.; Martin, Matthew T.; Weissman, Arthur; Kleinstreuer, Nicole C.; Mortensen, Holly M.; Reif, David M.; Rabinowitz, James R.; Setzer, R. Woodrow; Richard, Ann M.; Dix, David J.; Kavlock, Robert J.

    2011-01-01

    Understanding the potential health risks posed by environmental chemicals is a significant challenge elevated by the large number of diverse chemicals with generally uncharacterized exposures, mechanisms, and toxicities. The present study is a performance evaluation and critical analysis of assay results for an array of 292 high-throughput cell-free assays aimed at preliminary toxicity evaluation of 320 environmental chemicals in EPA's ToxCast TM project (Phase I). The chemicals (309 unique, 11 replicates) were mainly precursors or the active agent of commercial pesticides, for which a wealth of in vivo toxicity data is available. Biochemical HTS (high-throughput screening) profiled cell and tissue extracts using semi-automated biochemical and pharmacological methodologies to evaluate a subset of G-protein coupled receptors (GPCRs), CYP450 enzymes (CYPs), kinases, phosphatases, proteases, HDACs, nuclear receptors, ion channels, and transporters. The primary screen tested all chemicals at a relatively high concentration 25 μM concentration (or 10 μM for CYP assays), and a secondary screen re-tested 9132 chemical-assay pairs in 8-point concentration series from 0.023 to 50 μM (or 0.009-20 μM for CYPs). Mapping relationships across 93,440 chemical-assay pairs based on half-maximal activity concentration (AC50) revealed both known and novel targets in signaling and metabolic pathways. The primary dataset, summary data and details on quality control checks are available for download at (http://www.epa.gov/ncct/toxcast/).

  18. Chemical composition and antimicrobial activity of the essential oils of Pinus pinaster

    OpenAIRE

    Nouara Ait Mimoune; Djouher Ait Mimoune; Aziza Yataghene

    2013-01-01

    Objective: To investigate the antimicrobial activity and chemical composition of essential oils of Pinus pinaster. Methods: Essential oils were extracted from the needles by hydrodistillation. The chemical composition of the obtained essential oils was analyzed using GC-MS technique. The antimicrobial potential has been tested against six microorganisms performing the disc diffusion assay. Results: Twenty-three components have been identified. β-caryophyllene (30.9%) and β-seli...

  19. Fault Diagnosis Based on Chemical Sensor Data with an Active Deep Neural Network.

    Science.gov (United States)

    Jiang, Peng; Hu, Zhixin; Liu, Jun; Yu, Shanen; Wu, Feng

    2016-10-13

    Big sensor data provide significant potential for chemical fault diagnosis, which involves the baseline values of security, stability and reliability in chemical processes. A deep neural network (DNN) with novel active learning for inducing chemical fault diagnosis is presented in this study. It is a method using large amount of chemical sensor data, which is a combination of deep learning and active learning criterion to target the difficulty of consecutive fault diagnosis. DNN with deep architectures, instead of shallow ones, could be developed through deep learning to learn a suitable feature representation from raw sensor data in an unsupervised manner using stacked denoising auto-encoder (SDAE) and work through a layer-by-layer successive learning process. The features are added to the top Softmax regression layer to construct the discriminative fault characteristics for diagnosis in a supervised manner. Considering the expensive and time consuming labeling of sensor data in chemical applications, in contrast to the available methods, we employ a novel active learning criterion for the particularity of chemical processes, which is a combination of Best vs. Second Best criterion (BvSB) and a Lowest False Positive criterion (LFP), for further fine-tuning of diagnosis model in an active manner rather than passive manner. That is, we allow models to rank the most informative sensor data to be labeled for updating the DNN parameters during the interaction phase. The effectiveness of the proposed method is validated in two well-known industrial datasets. Results indicate that the proposed method can obtain superior diagnosis accuracy and provide significant performance improvement in accuracy and false positive rate with less labeled chemical sensor data by further active learning compared with existing methods.

  20. Fault Diagnosis Based on Chemical Sensor Data with an Active Deep Neural Network

    Science.gov (United States)

    Jiang, Peng; Hu, Zhixin; Liu, Jun; Yu, Shanen; Wu, Feng

    2016-01-01

    Big sensor data provide significant potential for chemical fault diagnosis, which involves the baseline values of security, stability and reliability in chemical processes. A deep neural network (DNN) with novel active learning for inducing chemical fault diagnosis is presented in this study. It is a method using large amount of chemical sensor data, which is a combination of deep learning and active learning criterion to target the difficulty of consecutive fault diagnosis. DNN with deep architectures, instead of shallow ones, could be developed through deep learning to learn a suitable feature representation from raw sensor data in an unsupervised manner using stacked denoising auto-encoder (SDAE) and work through a layer-by-layer successive learning process. The features are added to the top Softmax regression layer to construct the discriminative fault characteristics for diagnosis in a supervised manner. Considering the expensive and time consuming labeling of sensor data in chemical applications, in contrast to the available methods, we employ a novel active learning criterion for the particularity of chemical processes, which is a combination of Best vs. Second Best criterion (BvSB) and a Lowest False Positive criterion (LFP), for further fine-tuning of diagnosis model in an active manner rather than passive manner. That is, we allow models to rank the most informative sensor data to be labeled for updating the DNN parameters during the interaction phase. The effectiveness of the proposed method is validated in two well-known industrial datasets. Results indicate that the proposed method can obtain superior diagnosis accuracy and provide significant performance improvement in accuracy and false positive rate with less labeled chemical sensor data by further active learning compared with existing methods. PMID:27754386

  1. Fault Diagnosis Based on Chemical Sensor Data with an Active Deep Neural Network

    Directory of Open Access Journals (Sweden)

    Peng Jiang

    2016-10-01

    Full Text Available Big sensor data provide significant potential for chemical fault diagnosis, which involves the baseline values of security, stability and reliability in chemical processes. A deep neural network (DNN with novel active learning for inducing chemical fault diagnosis is presented in this study. It is a method using large amount of chemical sensor data, which is a combination of deep learning and active learning criterion to target the difficulty of consecutive fault diagnosis. DNN with deep architectures, instead of shallow ones, could be developed through deep learning to learn a suitable feature representation from raw sensor data in an unsupervised manner using stacked denoising auto-encoder (SDAE and work through a layer-by-layer successive learning process. The features are added to the top Softmax regression layer to construct the discriminative fault characteristics for diagnosis in a supervised manner. Considering the expensive and time consuming labeling of sensor data in chemical applications, in contrast to the available methods, we employ a novel active learning criterion for the particularity of chemical processes, which is a combination of Best vs. Second Best criterion (BvSB and a Lowest False Positive criterion (LFP, for further fine-tuning of diagnosis model in an active manner rather than passive manner. That is, we allow models to rank the most informative sensor data to be labeled for updating the DNN parameters during the interaction phase. The effectiveness of the proposed method is validated in two well-known industrial datasets. Results indicate that the proposed method can obtain superior diagnosis accuracy and provide significant performance improvement in accuracy and false positive rate with less labeled chemical sensor data by further active learning compared with existing methods.

  2. Phyto chemical and biological studies of certain plants with potential radioprotective activity

    International Nuclear Information System (INIS)

    Sherif, N.H.M.I

    2008-01-01

    One of the promising directions of radiation protection development is the search for natural radioprotective agents.The present work includes: I- Screening of certain edible and medicinal plants growing in Egypt for their radioprotective activities. II- Detailed phyto chemical and biolo-activity studies of the dried leaves of brassaia actinophylla endl. comprising: A-Phyto chemical screening and proximate analysis. B-Investigation of lipoidal matter. C- Isolation, characterization and structure elucidation of phenolic constituents. D- Isolation, characterization and structure elucidation of saponin constituents. E- Evaluation of radioprotective and antitumor activities. I- Evaluation of potential radioprotective activities of certain herbs: In vivo biological screening designed to investigate the radioprotective role of 70% ethanol extract of 11 different herbals was carried out by measuring the lipid peroxide content, as well as the activities of two antioxidant enzymes; viz glutathione, and superoxide dismutase in blood and liver tissues 1 and 7 days after radiation exposure. II : Phyto chemical and biolo-activity studies of the dried leaves of brassaia actinophylla Endl A : preliminary phyto chemical screening, determination and TLC examination of successive extractives. B : Investigation of lipoidal matter. GLC of unsaponifiable matter (USM)

  3. Analysis and classification of physical and chemical methods of fuel activation

    Directory of Open Access Journals (Sweden)

    Fedorchak Viktoriya

    2015-12-01

    Full Text Available The offered article explores various research studies, developed patents in terms of physical and chemical approaches to the activation of fuel. In this regard, national and foreign researches in the field of fuels activators with different principles of action were analysed, evaluating their pros and cons. The article also intends to classify these methods and compare them regarding diverse desired results and types of fuels used. In terms of physical and chemical influences on fuels and the necessity of making constructive changes in the fuel system of internal combustion engines, an optimal approach was outlined.

  4. Textural and chemical properties of zinc chloride activated carbons prepared from pistachio-nut shells

    International Nuclear Information System (INIS)

    Yang Ting; Lua, Aik Chong

    2006-01-01

    The effects of activation temperature on the textural and chemical properties of the activated carbons prepared from pistachio-nut shells using zinc chloride activation under both inert nitrogen gas atmosphere and vacuum condition were studied. Relatively low temperature of 400 deg. C was beneficial for the development of pore structures. Too high an activation temperature would lead to sintering of volatiles and shrinkage of the carbon structure. The microstructures and microcrystallinity of the activated carbons prepared were examined by scanning electron microscope and powder X-ray diffraction techniques, respectively, while Fourier transform infrared spectra determined the changes in the surface functional groups at the various stages of preparation

  5. Textural and chemical properties of zinc chloride activated carbons prepared from pistachio-nut shells

    Energy Technology Data Exchange (ETDEWEB)

    Ting, Yang [School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore); Lua, Aik Chong [School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore)

    2006-12-10

    The effects of activation temperature on the textural and chemical properties of the activated carbons prepared from pistachio-nut shells using zinc chloride activation under both inert nitrogen gas atmosphere and vacuum condition were studied. Relatively low temperature of 400 deg. C was beneficial for the development of pore structures. Too high an activation temperature would lead to sintering of volatiles and shrinkage of the carbon structure. The microstructures and microcrystallinity of the activated carbons prepared were examined by scanning electron microscope and powder X-ray diffraction techniques, respectively, while Fourier transform infrared spectra determined the changes in the surface functional groups at the various stages of preparation.

  6. Analysis of essential oils from Voacanga africana seeds at different hydrodistillation extraction stages: chemical composition, antioxidant activity and antimicrobial activity.

    Science.gov (United States)

    Liu, Xiong; Yang, Dongliang; Liu, Jiajia; Ren, Na

    2015-01-01

    In this study, essential oils from Voacanga africana seeds at different extraction stages were investigated. In the chemical composition analysis, 27 compounds representing 86.69-95.03% of the total essential oils were identified and quantified. The main constituents in essential oils were terpenoids, alcohols and fatty acids accounting for 15.03-24.36%, 21.57-34.43% and 33.06-57.37%, respectively. Moreover, the analysis also revealed that essential oils from different extraction stages possessed different chemical compositions. In the antioxidant evaluation, all analysed oils showed similar antioxidant behaviours, and the concentrations of essential oils providing 50% inhibition of DPPH-scavenging activity (IC50) were about 25 mg/mL. In the antimicrobial experiments, essential oils from different extraction stages exhibited different antimicrobial activities. The antimicrobial activity of oils was affected by extraction stages. By controlling extraction stages, it is promising to obtain essential oils with desired antimicrobial activities.

  7. Gamma irradiation effect on the chemical composition and the antioxidant activity of Ipomoea batatas L

    Energy Technology Data Exchange (ETDEWEB)

    Tahir, D., E-mail: dtahir@fmipa.unhas.ac.id; Halide, H., E-mail: dtahir@fmipa.unhas.ac.id; Kurniawan, D. [Department of Physics, Hasanuddin University, Makassar 90245 (Indonesia); Wahab, A. W. [Department of Chemistry, Hasanuddin University, Makassar 90245 (Indonesia)

    2014-09-25

    The chemical composition and antioxidant activity of Ipomoea batatas L. (sweet potato) were studied by x-ray fluorescence (XRF) spectroscopy, Fourier transform infrared spectroscopy, and by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity. The irradiation treatment was performed by using Cs-137 as a gamma sources in experimental equipment. Treatment by irradiation emerges as a possible conservation technique that has been tested successfully in several food products. The amount of chemical composition was changed and resulting new chemical for absorbed dose 40 mSv. Interestingly, it was found that gamma irradiation significantly increased the antioxidant activity, as measured by DPPH radical scavenging capacity. The antioxidant activity of Ipomoea batatas L. extract was dramatically increased in the non-irradiated sample to the sample irradiated at 40 mSv. These results indicate that gamma irradiation of Ipomoea batatas L. extract can enhance its antioxidant activity through the formation of a new chemical compound. Based on these results, increased antioxidant activity of Ipomoea batatas L. extracts by gamma rays can be applied to various industries, especially cosmetics, foodstuffs, and pharmaceuticals.

  8. Re-Design Pompa Sentrifugal Double Admission dengan Fluida Kerja Semi Lean Benfield Solution (K2CO3 pada Kapasitas 700 m3/h dan Head 275.8 m, (STUDI KASUS : PT. PETROKIMIA GRESIK

    Directory of Open Access Journals (Sweden)

    Fathur Rahim

    2013-09-01

    Full Text Available Penggunaan pompa sentrifugal dalam dunia industri, khususnya di PT. Petrokimia Gresik memiliki peran yang sangat penting, terutama untuk memindahkan fluida kerja dari satu tempat ke tempat lain. PT. Petrokima Gresik dalam menggunakan jenis pompa untuk mengalirkan semi lean benfield solution ( yang berfungsi sebagai absorber dalam proses pembuatan amoniak. Seiring berjalannya waktu, kapasitas pompa sentrifugal double admission yang semula 582,3ingin ditingkatkan menjadi 700 Oleh karena itu, dilakukan perancangan ulang pompa sentrifugal double admission untuk fluida kerja semi lean benfield solution ( .Setelah itu dilakukan perancangan ulang pompa dengan data yang telah diolah meliputi perancangan poros, impeller dengan bentuk sudu double curvature, volute, pasak dan bearing. Dari perancangan ulang, didapatkan desain pompa sentrifugal double admission untuk fluida kerja semi lean benfield solution ( yang sesuai dengan kapasitas 700pada head 275,8 m serta daya BHP sebesar 886 Kwatt dengan effisiensi 74%.

  9. Chemical features of Ganoderma polysaccharides with antioxidant, antitumor and antimicrobial activities.

    Science.gov (United States)

    Ferreira, Isabel C F R; Heleno, Sandrina A; Reis, Filipa S; Stojkovic, Dejan; Queiroz, Maria João R P; Vasconcelos, M Helena; Sokovic, Marina

    2015-06-01

    Ganoderma genus comprises one of the most commonly studied species worldwide, Ganoderma lucidum. However, other Ganoderma species have been also reported as important sources of bioactive compounds. Polysaccharides are important contributors to the medicinal properties reported for Ganoderma species, as demonstrated by the numerous publications, including reviews, on this matter. Yet, what are the chemical features of Ganoderma polysaccharides that have bioactivity? In the present manuscript, the chemical features of Ganoderma polysaccharides with reported antioxidant, antitumor and antimicrobial activities (the most studied worldwide) are analyzed in detail. The composition of sugars (homo- versus hetero-glucans and other polysaccharides), type of glycosidic linkages, branching patterns, and linkage to proteins are discussed. Methods for extraction, isolation and identification are evaluated and, finally, the bioactivity of polysaccharidic extracts and purified compounds are discussed. The integration of data allows deduction of structure-activity relationships and gives clues to the chemical aspects involved in Ganoderma bioactivity. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Differential effects of environmental chemicals and food contaminants on adipogenesis, biomarker release and PPARγ activation

    DEFF Research Database (Denmark)

    Taxvig, Camilla; Sørensen, Karin Dreisig; Boberg, Julie

    2012-01-01

    Eleven environmental relevant chemicals were investigated for their ability to affect adipogenesis in vitro, biomarker release from adipocytes and PPARα and γ activation. We found that butylparaben stimulated adipogenesis in 3T3-L1 adipocytes and increased release of leptin, adiponectin and resis...

  11. Phoenix dactylifera L. spathe essential oil: Chemical composition and repellent activity against the yellow fever mosquito

    Science.gov (United States)

    Date palm, Phoenix dactylifera L. (Arecaceae), grows commonly in the Arabian Peninsula and is traditionally used to treat various diseases. The aim of the present study was to identify chemical composition of the essential oil and to investigate the repellent activity. The essential oil of P. dacty...

  12. Passive dosing of pyrethroid insecticides to Daphnia magna: Expressing excess toxicity by chemical activity

    DEFF Research Database (Denmark)

    Nørgaard Schmidt, Stine; Gan, Jay; Kretschmann, A. C.

    2015-01-01

    ) Effective chemical activities resulting in 50% immobilisation (Ea50) will be estimated from pyrethroid EC50 values via the correlation of sub-cooled liquid solubility (S L, [mmol/L], representing a=1) and octanol to water partitioning ratios (Kow), (3) The excess toxicity observed for pyrethroids...

  13. Chemical composition and anti-bacterial activity of essential oil from ...

    African Journals Online (AJOL)

    This work assesses the chemical compositions and in vitro anti-bacterial activities of seed essential oil from Cedrela sinesis (A. Juss.) Roem. seed. which has abundant mineral elements such as K, Ca, Fe. The fatty acid profiles of seed essential oil are characterized by considerable unsaturated fatty acids (90.39%) ...

  14. Chemical composition, in vitro antioxidant, antimicrobial and insecticidal activities of essential oil from Cladanthus arabicus

    Science.gov (United States)

    The essential oil obtained from the aerial parts of Cladanthus arabicus (L.) Cass was studied for its chemical composition, antioxidant, antimicrobial and insecticidal activities. The essential oil (EO) was analyzed by GC-MS. Sixty seven compounds representing 94.2% of the oil were identified. The m...

  15. Lantana montevidensis Essential Oil: Chemical Composition and Mosquito Repellent Activity against Aedes aegypti

    Science.gov (United States)

    The essential oil (EO) of Lantana montevidensis (Spreng.) Briq. (L. sellowiana Link & Otto) was investigated for its chemical composition and mosquito repellent activity. The essential oil obtained by hydrodistillation of aerial plant parts was analyzed by GC-FID and GC-MS. The major constituents we...

  16. 76 FR 76935 - Impact of Implementing the Chemical Weapons Convention (CWC) on Commercial Activities Involving...

    Science.gov (United States)

    2011-12-09

    ..., titled ``Protection of Advanced Biotechnology,'' calls for the President to certify to Congress on an annual basis that ``the legitimate commercial activities and interests of chemical, biotechnology, and pharmaceutical firms in the United States are not being significantly harmed by the limitations of the Convention...

  17. Effect of Separation Method on Chemical Composition and Insecticidal Activity of Lamiaceae Isolates

    Czech Academy of Sciences Publication Activity Database

    Sajfrtová, Marie; Sovová, Helena; Karban, Jindřich; Rochová, Kristina; Pavela, R.; Barnet, M.

    2013-01-01

    Roč. 47, MAY (2013), s. 69-77 ISSN 0926-6690 R&D Projects: GA MŠk 2B06049; GA TA ČR TA01010578 Institutional support: RVO:67985858 Keywords : supercritical fluid extraction * iInsecticidal activity * lamiaceae Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 3.208, year: 2013

  18. Fenton-Driven Chemical Regeneration of MTBE-Spent Granular Activated Carbon -- A Pilot Study

    Science.gov (United States)

    MTBE-spent granular activated carbon (GAC) underwent 3 adsorption/oxidation cycles. Pilot-scale columns were intermittently placed on-line at a ground water pump and treat facility, saturated with MTBE, and regenerated with H2O2 under different chemical, physical, and operational...

  19. Chemical composition and antimicrobial activity of oregano (Lippia palmeri S. Wats) essential oil

    OpenAIRE

    Ortega-Nieblas, Ma. Magdalena; Robles-Burgueño, Ma. Refugio; Acedo-Félix, Evelia; González-León, Alberto; Morales-Trejo, Adriana; Vázquez-Moreno, Luz

    2011-01-01

    The chemical composition and antimicrobial activity of Lippia palmeri S. Wats essential oil extracted from plants collected of two localities (Álamos and Puerto del Orégano) in the State of Sonora, México, was examined. Essential oils (EO) were obtained from oregano leaves by steam distillation, analyzed by gas chromatography coupled with a mass spectrometer, and their antimicrobial activity against human pathogens investigated by disc diffusion. Álamos and Puerto del Orégano essential oils (...

  20. Chemical composition and antibacterial activity of essential oils against human pathogenic bacteria

    OpenAIRE

    Sokovic, M.; Marin, P.D.; Brkic, D.; Griensven, van, L.J.L.D.

    2008-01-01

    The chemical composition and antibacterial activity of essential oils from 10 aromatic plants Matricaria chamommilla, Mentha piperita, M. spicata, Lavandula angustifolia, Ocimum basilicum, Thymus vulgaris, Origanum vulgare, Salvia officinalis, Citrus limon and C. aurantium have been determined. Antibacterial activity of these oils and their components; i.e. linalyl acetate, linalool, limonene, pinene, ß-pinene, 1,8-cineole, camphor, carvacrol, thymol and menthol were assayed against a variety...

  1. The Electrochemical Characteristics of Hybrid Capacitor Prepared by Chemical Activation of NaOH

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jeong Eun; Bae, Ga Yeong; Yang, Jeong Min; Lee, Jong Dae [Chungbuk National Univ., Chungju (Korea, Republic of)

    2013-06-15

    Active carbons with high specific surface area and micro pore structure were prepared from the coconut shell char using the chemical activation method of NaOH. The preparation process has been optimized through the analysis of experimental variables such as activating chemical agents to char ratio and the flow rate of gas during carbonization. The active carbons with the surface area (2,481m{sup 2}/g) and mean pore size (2.32 nm) were obtained by chemical activation with NaOH. The electrochemical performances of hybrid capacitor were investigated using LiMn{sub 2}O{sub 4}, LiCoO{sub 2} as the positive electrode and prepared active carbon as the negative electrode. The electrochemical behaviors of hybrid capacitor using organic electrolytes (LiPF{sub 6}, TEABF{sub 4}) were characterized by constant current charge/discharge, cyclic voltammetry, cycle and leakage tests. The hybrid capacitor using LiMn{sub 2}O{sub 4}/AC electrodes had better capacitance than other hybrid systems and was able to deliver a specific energy as high as 131 Wh/kg at a specific power of 1,448 W/kg.

  2. The Electrochemical Characteristics of Hybrid Capacitor Prepared by Chemical Activation of NaOH

    International Nuclear Information System (INIS)

    Choi, Jeong Eun; Bae, Ga Yeong; Yang, Jeong Min; Lee, Jong Dae

    2013-01-01

    Active carbons with high specific surface area and micro pore structure were prepared from the coconut shell char using the chemical activation method of NaOH. The preparation process has been optimized through the analysis of experimental variables such as activating chemical agents to char ratio and the flow rate of gas during carbonization. The active carbons with the surface area (2,481m 2 /g) and mean pore size (2.32 nm) were obtained by chemical activation with NaOH. The electrochemical performances of hybrid capacitor were investigated using LiMn 2 O 4 , LiCoO 2 as the positive electrode and prepared active carbon as the negative electrode. The electrochemical behaviors of hybrid capacitor using organic electrolytes (LiPF 6 , TEABF 4 ) were characterized by constant current charge/discharge, cyclic voltammetry, cycle and leakage tests. The hybrid capacitor using LiMn 2 O 4 /AC electrodes had better capacitance than other hybrid systems and was able to deliver a specific energy as high as 131 Wh/kg at a specific power of 1,448 W/kg

  3. Recovery of microbial diversity and activity during bioremediation following chemical oxidation of diesel contaminated soils.

    Science.gov (United States)

    Sutton, Nora B; Langenhoff, Alette A M; Lasso, Daniel Hidalgo; van der Zaan, Bas; van Gaans, Pauline; Maphosa, Farai; Smidt, Hauke; Grotenhuis, Tim; Rijnaarts, Huub H M

    2014-03-01

    To improve the coupling of in situ chemical oxidation and in situ bioremediation, a systematic analysis was performed of the effect of chemical oxidation with Fenton's reagent, modified Fenton's reagent, permanganate, or persulfate, on microbial diversity and activity during 8 weeks of incubation in two diesel-contaminated soils (peat and fill). Chemical oxidant and soil type affected the microbial community diversity and biodegradation activity; however, this was only observed following treatment with Fenton's reagent and modified Fenton's reagent, and in the biotic control without oxidation. Differences in the highest overall removal efficiencies of 69 % for peat (biotic control) and 59 % for fill (Fenton's reagent) were partially explained by changes in contaminant soil properties upon oxidation. Molecular analysis of 16S rRNA and alkane monooxygenase (alkB) gene abundances indicated that oxidation with Fenton's reagent and modified Fenton's reagent negatively affected microbial abundance. However, regeneration occurred, and final relative alkB abundances were 1-2 orders of magnitude higher in chemically treated microcosms than in the biotic control. 16S rRNA gene fragment fingerprinting with DGGE and prominent band sequencing illuminated microbial community composition and diversity differences between treatments and identified a variety of phylotypes within Alpha-, Beta-, and Gammaproteobacteria. Understanding microbial community dynamics during coupled chemical oxidation and bioremediation is integral to improved biphasic field application.

  4. A coupled theory for chemically active and deformable solids with mass diffusion and heat conduction

    Science.gov (United States)

    Zhang, Xiaolong; Zhong, Zheng

    2017-10-01

    To analyse the frequently encountered thermo-chemo-mechanical problems in chemically active material applications, we develop a thermodynamically-consistent continuum theory of coupled deformation, mass diffusion, heat conduction and chemical reaction. Basic balance equations of force, mass and energy are presented at first, and then fully coupled constitutive laws interpreting multi-field interactions and evolving equations governing irreversible fluxes are constructed according to the energy dissipation inequality and the chemical kinetics. To consider the essential distinction between mass diffusion and chemical reactions in affecting free energy and dissipations of a highly coupled system, we regard both the concentrations of diffusive species and the extent of reaction as independent state variables. This new formulation then distinguishes between the energy contribution from the diffusive species entering the solid and that from the subsequent chemical reactions occurring among these species and the host solid, which not only interact with stresses or strains in different manners and on different time scales, but also induce different variations of solid microstructures and material properties. Taking advantage of this new description, we further establish a specialized isothermal model to predict precisely the transient chemo-mechanical response of a swelling solid with a proposed volumetric constraint that accounts for material incompressibility. Coupled kinetics is incorporated to capture the volumetric swelling of the solid caused by imbibition of external species and the simultaneous dilation arised from chemical reactions between the diffusing species and the solid. The model is then exemplified with two numerical examples of transient swelling accompanied by chemical reaction. Various ratios of characteristic times of diffusion and chemical reaction are taken into account to shed light on the dependency on kinetic time scales of evolution patterns for

  5. Shape-dependent guidance of active Janus particles by chemically patterned surfaces

    Science.gov (United States)

    Uspal, W. E.; Popescu, M. N.; Tasinkevych, M.; Dietrich, S.

    2018-01-01

    Self-phoretic chemically active Janus particles move by inducing—via non-equilibrium chemical reactions occurring on their surfaces—changes in the chemical composition of the solution in which they are immersed. This process leads to gradients in chemical composition along the surface of the particle, as well as along any nearby boundaries, including solid walls. Chemical gradients along a wall can give rise to chemi-osmosis, i.e., the gradients drive surface flows which, in turn, drive flow in the volume of the solution. This bulk flow couples back to the particle, and thus contributes to its self-motility. Since chemi-osmosis strongly depends on the molecular interactions between the diffusing molecular species and the wall, the response flow induced and experienced by a particle encodes information about any chemical patterning of the wall. Here, we extend previous studies on self-phoresis of a sphere near a chemically patterned wall to the case of particles with rod-like, elongated shape. We focus our analysis on the new phenomenology potentially emerging from the coupling—which is inoperative for a spherical shape—of the elongated particle to the strain rate tensor of the chemi-osmotic flow. Via detailed numerical calculations, we show that the dynamics of a rod-like particle exhibits a novel ‘edge-following’ steady state: the particle translates along the edge of a chemical step at a steady distance from the step and with a steady orientation. Moreover, within a certain range of system parameters, the edge-following state co-exists with a ‘docking’ state (the particle stops at the step, oriented perpendicular to the step edge), i.e., a bistable dynamics occurs. These findings are rationalized as a consequence of the competition between the fluid vorticity and the rate of strain by using analytical theory based on the point-particle approximation which captures quasi-quantitatively the dynamics of the system.

  6. Formulation of new oxydizing microemulsions for the chemical decontamination of war toxic agents. Activity report. Formulation de nouvelles microemulsions oxydantes pour la decontamination chimique de toxiques de guerre

    Energy Technology Data Exchange (ETDEWEB)

    Eychenne, P.; Rico, I.; Perez, E.

    1994-01-01

    A series of reactions--hydrolysis of para-nitrophenyl diphenyl phosphate (PNDP) and oxydation of sulfurous compounds (tetrahydrothophene and semi-mustard gas)--enabled the authors to simulate the degradation of two particularly harmful war toxic agents: paraoxon and mustard gas. The best decontaminating formulations obtained were the following: (1) Paraoxon degradation: PNDP, 2.51 times 10 to the minus fourth power M; cetyl pyridinium chloride (CPCI), .008 M; K2CO3, .474 M; glycerol/water = 1.7; t(sub 1/2) = 48 sec. (2) Mustard-gas degradation: tetrahydrothiophene oxidation: tetrahydrothiophene, 0,14 M; CPCI, .008 M; magnesium monoperoxyphthalate (MMPP), .075 M; glycerol/water = 1.7; t(sub 1/2) = 102 sec; efficiency = 71%; sulfoxide = 69% sulfone = 31%. -- semi-mustard gas oxydation: semi-mustard gas, .07 M; CPCI, .008 M; MMPP, .075 M; glycerol/water = 1.7; 100% efficiency in 3 minutes.

  7. Chemical Composition and Antimicrobial Activity of Echinophora spinosa L. (Apiaceae Essential Oil

    Directory of Open Access Journals (Sweden)

    Jasmina M. Glamočlija

    2011-01-01

    Full Text Available The present study was undertaken to investigate the chemical composition and effectiveness of the essential oil isolated from Echinophora spinosa on different bacterial and fungal species. Chemical analysis (GC/MS showed that δ³-carene (60,86 %, α-phellandrene (7,12%, p-cymene (6,22 %, myrcene (4,82 % and β-phellandrene (2,73 % were dominant components in this oil. Essential oil tested showed good antimicrobial activity. Antimicrobial potential of this oil was higher than potential of commercial antimicrobial drugs tested, streptomycin, bifonozole and ketoconazole.

  8. Natural and active chemical remediation of toxic metals and radionuclides in the aquatic environment

    International Nuclear Information System (INIS)

    McPherson, G.; Pintauro, P.; O'Connor, S.; Zhang, J.; Gonzales, R.; Flowers, G.

    1993-01-01

    The focus of this research is the non-biological, chemical remediation of toxic heavy metals and radionuclides in aquatic environments. This Tulane/Xavier group includes researchers from Chemistry, Chemical Engineering, and Geology. Active methods using novel zeolites and ion exchange membranes are currently being evaluated for use in removing heavy metals from natural waters. In addition, field and laboratory studies of metal ion exchange reactions and competitive, heavy metal adsorption on clay substrates are underway to determine sediment metal sequestering capacity. A summary of progress to date and future work is presented

  9. Coupling of physical erosion and chemical weathering after phases of intense human activity

    Science.gov (United States)

    Schoonejans, Jerome; Vanacker, Veerle; Opfergelt, Sophie; Ameijeiras-Mariño, Yolanda; Kubik, Peter W.

    2014-05-01

    with long-term 10Be derived denudation rates, and tectonic uplift rates. Our data do not provide direct evidence of an imbalance between soil production and chemical weathering, despite more than 2000 years of intense human activity.

  10. Chemical composition and antibacterial activity of Opuntia ficus-indica f. inermis (cactus pear) flowers.

    Science.gov (United States)

    Ennouri, Monia; Ammar, Imene; Khemakhem, Bassem; Attia, Hamadi

    2014-08-01

    Opuntia ficus-indica f. inermis (cactus pear) flowers have wide application in folk medicine. However, there are few reports focusing on their biological activity and were no reports on their chemical composition. The nutrient composition and hexane extracts of Opuntia flowers at 4 flowering stages and their antibacterial and antifungal activities were investigated. The chemical composition showed considerable amounts of fiber, protein, and minerals. Potassium (K) was the predominant mineral followed by calcium (Ca), magnesium (Mg), sodium (Na), iron (Fe), and zinc (Zn). The main compounds in the various hexane extracts were 9.12-octadecadienoic acid (29-44%) and hexadecanoic acid (8.6-32%). The antibacterial activity tests showed that O. inermis hexane extracts have high effectiveness against Escherichia coli and Staphylococcus aureus, making this botanical source a potential contender as a food preservative or food control additive.

  11. 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.

  12. Chemical analysis and antioxidant activity in vitro of polysaccharides extracted from Boletus edulis.

    Science.gov (United States)

    Zhang, Anqiang; Xiao, Nannan; He, Pengfei; Sun, Peilong

    2011-12-01

    Boletus edulis is a well-known delicious mushroom. In this study, three crude polysaccharides (BEPF30, BEPF60 and BEPF80) were isolated from the fruiting bodies of B. edulis with boiling water. Chemical and physical characteristics of the three crude polysaccharides were investigated by the combination of chemical and instrumental analysis methods. Their antioxidant activities were investigated in vitro systems including hydroxyl assay, superoxide radical assay, reducing power and chelating activity. Among these three polysaccharides, BEPF60 showed more significant reducing power and chelating activity; and highest inhibitory effects on superoxide radical and hydroxyl radical. These results indicated that polysaccharides extracted from B. edulis might be employed as ingredients in healthy and functional food to alleviate the oxidative stress. Copyright © 2011 Elsevier B.V. All rights reserved.

  13. Sulfur dioxide adsorption by activated carbons having different textural and chemical properties

    Energy Technology Data Exchange (ETDEWEB)

    Nilgun Karatepe; Ilkun Orbak; Reha Yavuz; Ayse Ozyuguran [Istanbul Technical University, Istanbul (Turkey). Institute of Energy

    2008-11-15

    Activated carbons from Turkish lignite were prepared with different methods to investigate the influence of physico-chemical characteristics of the carbon materials on the sulfur dioxide (SO{sub 2}) adsorption. The effects of SO{sub 2} concentration, adsorption temperature, and sample particle size on adsorption were investigated using a thermogravimetric analysis system. An intraparticle diffusion model based on Knudsen diffusion and Freundlich isotherm (or Henry isotherm) was applied for predicting the amount of SO{sub 2} adsorbed. The textural and chemical properties of the activated carbon samples, resulted from the effects of activation conditions and demineralization of the carbon precursor, on the SO{sub 2} adsorption were also analyzed. 30 refs., 7 figs., 4 tabs.

  14. Chemical Composition and Antibacterial Activity of the Essential Oil of Vitex agnus-castus L. (Lamiaceae).

    Science.gov (United States)

    Gonçalves, Regiane; Ayres, Vanessa F S; Carvalho, Carlos E; Souza, Maria G M; Guimarães, Anderson C; Corrêa, Geone M; Martins, Carlos H G; Takeara, Renata; Silva, Eliane O; Crotti, Antônio E M

    2017-01-01

    Abnormal multiplication of oral bacteria causes dental caries and dental plaque. These diseases continue to be major public health concerns worldwide, mainly in developing countries. In this study, the chemical composition and antimicrobial activity of the essential oil of Vitex agnus-castus leaves (VAC‒EO) collected in the North of Brazil against a representative panel of cariogenic bacteria were investigated. The antimicrobial activity of VAC-EO was evaluated in terms of its minimum inhibitory concentration (MIC) values by using the broth microdilution method in 96-well microplates. The chemical constituents of VAC-EO were identified by gas chromatography (GC‒FID) and gas chromatography‒mass spectrometry (GC‒MS). VAC‒EO displayed some activity against all the investigated oral pathogens; MIC values ranged from 15.6 to 200 μg/mL. VAC-EO had promising activity against Streptococcus mutans (MIC= 15.6 μg/mL), Lactobacillus casei (MIC= 15.6 μg/mL), and Streptococcus mitis (MIC= 31.2 μg/mL). The compounds 1,8-cineole (23.8%), (E)-β-farnesene (14.6%), (E)-caryophyllene (12.5%), sabinene (11.4%), and α-terpinyl acetate (7.7%) were the major chemical constituents of VAC‒EO. VAC-EO displays antimicrobial activity against cariogenic bacteria. The efficacy of VAC-EO against S. mutans is noteworthy and should be further investigated.

  15. Chemical Composition and Antibacterial Activity of the Essential Oil of Vitex agnus-castus L. (Lamiaceae

    Directory of Open Access Journals (Sweden)

    REGIANE GONÇALVES

    Full Text Available ABSTRACT Abnormal multiplication of oral bacteria causes dental caries and dental plaque. These diseases continue to be major public health concerns worldwide, mainly in developing countries. In this study, the chemical composition and antimicrobial activity of the essential oil of Vitex agnus-castus leaves (VAC‒EO collected in the North of Brazil against a representative panel of cariogenic bacteria were investigated. The antimicrobial activity of VAC-EO was evaluated in terms of its minimum inhibitory concentration (MIC values by using the broth microdilution method in 96-well microplates. The chemical constituents of VAC-EO were identified by gas chromatography (GC‒FID and gas chromatography‒mass spectrometry (GC‒MS. VAC‒EO displayed some activity against all the investigated oral pathogens; MIC values ranged from 15.6 to 200 μg/mL. VAC-EO had promising activity against Streptococcus mutans (MIC= 15.6 μg/mL, Lactobacillus casei (MIC= 15.6 μg/mL, and Streptococcus mitis (MIC= 31.2 μg/mL. The compounds 1,8-cineole (23.8%, (E-β-farnesene (14.6%, (E-caryophyllene (12.5%, sabinene (11.4%, and α-terpinyl acetate (7.7% were the major chemical constituents of VAC‒EO. VAC-EO displays antimicrobial activity against cariogenic bacteria. The efficacy of VAC-EO against S. mutans is noteworthy and should be further investigated.

  16. Seasonal Variation, Chemical Composition and Antioxidant Activity of Brazilian Propolis Samples

    Directory of Open Access Journals (Sweden)

    Érica Weinstein Teixeira

    2010-01-01

    Full Text Available Total phenolic contents, antioxidant activity and chemical composition of propolis samples from three localities of Minas Gerais state (southeast Brazil were determined. Total phenolic contents were determined by the Folin–Ciocalteau method, antioxidant activity was evaluated by DPPH, using BHT as reference, and chemical composition was analyzed by GC/MS. Propolis from Itapecerica and Paula Cândido municipalities were found to have high phenolic contents and pronounced antioxidant activity. From these extracts, 40 substances were identified, among them were simple phenylpropanoids, prenylated phenylpropanoids, sesqui- and diterpenoids. Quantitatively, the main constituent of both samples was allyl-3-prenylcinnamic acid. A sample from Virginópolis municipality had no detectable phenolic substances and contained mainly triterpenoids, the main constituents being α- and β-amyrins. Methanolic extracts from Itapecerica and Paula Cândido exhibited pronounced scavenging activity towards DPPH, indistinguishable from BHT activity. However, extracts from Virginópolis sample exhibited no antioxidant activity. Total phenolic substances, GC/MS analyses and antioxidant activity of samples from Itapecerica collected monthly over a period of 1 year revealed considerable variation. No correlation was observed between antioxidant activity and either total phenolic contents or contents of artepillin C and other phenolic substances, as assayed by CG/MS analysis.

  17. Determination of Chemical States of Mercury on Activated Carbon Using XANES

    International Nuclear Information System (INIS)

    Takaoka, Masaki; Takeda, Nobuo; Oshita, Kazuyuki; Yamamoto, Takashi; Tanaka, Tsunehiro; Uruga, Tomoya

    2007-01-01

    Although the adsorption of mercury vapor onto activated carbon is a widely used technology to prevent environmental release, the adsorption mechanism is not clearly understood. In this study, we determined the chemical states of mercury on two kinds of activated carbon using X-ray absorption near-edge spectroscopy (XANES) to elucidate the adsorption mechanism. The adsorption experiments of elemental mercury onto activated carbon were conducted under air and nitrogen atmospheres at temperatures of 20 and 160 deg. C. Two types of activated carbon were prepared. X-ray absorption fine structure (XAFS) measurements were carried out on beamline BL01B1 at SPring-8. Hg-LIII edge XANES spectra suggested that chemical adsorption of elemental mercury on the activated carbon occurred in the 20-160 deg. C temperature range. According to the XANES spectra, a difference occurred in the chemical states of mercury between AC no. 1 and AC no. 2. The Hg XANES spectra on AC no. 1 were similar to those of Hg2Cl2 and HgS, and the Hg XANES spectra on AC no. 2 were similar to that of HgO, which suggested that nitric acid treatment removed sulfur from AC no. 1 and functional groups that were strong oxidizers on the surface of AC no. 2 created HgO. According to the EXAFS oscillation, a difference occurred in the chemical states of mercury on AC no. 1 between 20 and 160 deg. C. We found that impurities and oxidant functional groups on activated carbon play key roles in mercury adsorption

  18. Influence of copper nanoparticles on the physical-chemical properties of activated sludge.

    Directory of Open Access Journals (Sweden)

    Hong Chen

    Full Text Available The physical-chemical properties of activated sludge, such as flocculating ability, hydrophobicity, surface charge, settleability, dewaterability and bacteria extracellular polymer substances (EPS, play vital roles in the normal operation of wastewater treatment plants (WWTPs. The nanoparticles released from commercial products will enter WWTPs and can induce potential adverse effects on activated sludge. This paper focused on the effects of copper nanoparticles (CuNPs on these specific physical-chemical properties of activated sludge. It was found that most of these properties were unaffected by the exposure to lower CuNPs concentration (5 ppm, but different observation were made at higher CuNPs concentrations (30 and 50 ppm. At the higher CuNPs concentrations, the sludge surface charge increased and the hydrophobicity decreased, which were attributed to more Cu2+ ions released from the CuNPs. The carbohydrate content of EPS was enhanced to defense the toxicity of CuNPs. The flocculating ability was found to be deteriorated due to the increased cell surface charge, the decreased hydrophobicity, and the damaged cell membrane. The worsened flocculating ability made the sludge flocs more dispersed, which further increased the toxicity of the CuNPs by increasing the availability of the CuNPs to the bacteria present in the sludge. Further investigation indicated that the phosphorus removal efficiency decreased at higher CuNPs concentrations, which was consistent with the deteriorated physical-chemical properties of activated sludge. It seems that the physical-chemical properties can be used as an indicator for determining CuNPs toxicity to the bacteria in activated sludge. This work is important because bacteria toxicity effects to the activated sludge caused by nanoparticles may lead to the deteriorated treatment efficiency of wastewater treatment, and it is therefore necessary to find an easy way to indicate this toxicity.

  19. Anticholinesterase activity and chemical profile of an active chromatographic fraction of ethanolic extract from Bellis perennis L. (Asteraceae) flowers

    International Nuclear Information System (INIS)

    Marques, Thiago Henrique Costa; Santos, Pauline Sousa dos; Freitas, Rivelilson Mendes de; Carvalho, Rusbene Bruno Fonseca de; Melo, Cassio Herbert Santos de; David, Juceni Pereira; David, Jorge Mauricio; Lima, Luciano Silva

    2013-01-01

    This work describes the isolation of an active flavonoid fraction and identification of isorhamnetin 3-O-β-D-(6’’-acetyl)- alactopyranoside from flowers of B. perennis, and also the evaluation of anticholinesterase (AChE) activity of ethanolic extract from flowers (EEF) and the active fraction. The chemical structure of the flavonoid was defined on the basis of spectroscopic 1 H NMR, IR and UV data. EEF or flavonoid reduces AChE activity in vivo, while flavonoid also reduces AChE activity in vitro, showing a value of 1.49 μM for 50% inhibitory concentration (IC 50 ), suggesting potential use as an insecticide or in the treatment of neurodegenerative diseases such as Alzheimer’s disease. (author)

  20. Effect of biological and chemical preparations on peroxidase activity in leaves of tomato plants

    Directory of Open Access Journals (Sweden)

    Yulia Kolomiets

    2016-10-01

    Full Text Available In terms of treating tomato variety Chaika with chemical preparations with active substances if aluminum phosphate, 570 g/l + phosphorous acid 80 g/,l and mankotseb in concentration of 640 g/kg, the maximum increase in peroxidase activity in leaves of plants was observed in12 hours. In terms of use of biological preparations based on living cells Bacillus subtilis and Azotobacter chroococcum its activity was maximum in 24 hours and ranged from 77.7 to 112.7 un.mg-1•s-1

  1. Chemical modification, antioxidant and α-amylase inhibitory activities of corn silk polysaccharides.

    Science.gov (United States)

    Chen, Shuhan; Chen, Haixia; Tian, Jingge; Wang, Yanwei; Xing, Lisha; Wang, Jia

    2013-10-15

    Water-soluble corn silk polysaccharides (CSPS) were chemically modified to obtain their sulfated, acetylated and carboxymethylated derivatives. Chemical characterization and bioactivities of CSPS and its derivatives were comparatively investigated by chemical methods, gas chromatography, gel filtration chromatography, scanning electron microscope, infrared spectroscopy and circular dichroism spectroscopy, scavenging DPPH free radical assay, scavenging hydroxyl radical assay, ferric reducing power assay, lipid peroxidation inhibition assay and α-amylase activity inhibitory assay, respectively. Among the three derivatives, carboxylmethylated polysaccharide (C-CSPS) demonstrated higher solubility, narrower molecular weight distribution, lower intrinsic viscosity, a hyperbranched conformation, significantly higher antioxidant and α-amylase inhibitory abilities compared with the native polysaccharide and other derivatives. C-CSPS might be used as a novel nutraceutical agent for human consumption. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Thermally activated reaction–diffusion-controlled chemical bulk reactions of gases and solids

    Directory of Open Access Journals (Sweden)

    S. Möller

    2015-01-01

    Full Text Available The chemical kinetics of the reaction of thin films with reactive gases is investigated. The removal of thin films using thermally activated solid–gas to gas reactions is a method to in-situ control deposition inventory in vacuum and plasma vessels. Significant scatter of experimental deposit removal rates at apparently similar conditions was observed in the past, highlighting the need for understanding the underlying processes. A model based on the presence of reactive gas in the films bulk and chemical kinetics is presented. The model describes the diffusion of reactive gas into the film and its chemical interaction with film constituents in the bulk using a stationary reaction–diffusion equation. This yields the reactive gas concentration and reaction rates. Diffusion and reaction rate limitations are depicted in parameter studies. Comparison with literature data on tokamak co-deposit removal results in good agreement of removal rates as a function of pressure, film thickness and temperature.

  3. Decolorization and chemical regeneration of granular activated carbon used in citric acid refining

    Directory of Open Access Journals (Sweden)

    Kang Sun

    2009-04-01

    Full Text Available Citric acid fermentation (CAF liquor decolorization by granular activated carbon (GAC was studied and an improved chemical regeneration method of the exhausted GAC by the color of CAF liquor was investigated. The effects of the GAC dosage, time and temperature on the decoloring efficiency (DE % were studied. The DE % of the original GAC was 91 %. The regeneration efficiency (RE % using chemical regents was 104 % of the original GAC. Hot water as cheap reagent was found to be much helpful to the regeneration efficiency. Using oxidant and surfactant in addition to just using NaOH solution can recover 10 % more adsorption capacity of renewed GAC. The adding dosage of oxidant is good at 3 % of exhausted GAC weight; that of surfactant is good at 0.1 %. Comparing with steam regeneration method, high regeneration yield (> 95 % of chemical method was an attractive economic factor. The results of this investigation can be as helpful reference for citric acid manufacturer expanding profits.

  4. Effect of mechanical activation on structure changes and reactivity in further chemical modification of lignin.

    Science.gov (United States)

    Zhao, Xiaohong; Zhang, Yanjuan; Hu, Huayu; Huang, Zuqiang; Yang, Mei; Chen, Dong; Huang, Kai; Huang, Aimin; Qin, Xingzhen; Feng, Zhenfei

    2016-10-01

    Lignin was treated by mechanical activation (MA) in a customized stirring ball mill, and the structure and reactivity in further esterification were studied. The chemical structure and morphology of MA-treated lignin and the esterified products were analyzed by chemical analysis combined with UV/vis spectrometer, FTIR,NMR, SEM and particle size analyzer. The results showed that MA contributed to the increase of aliphatic hydroxyl, phenolic hydroxyl, carbonyl and carboxyl groups but the decrease of methoxyl groups. Moreover, MA led to the decrease of particle size and the increase of specific surface area and roughness of surface in lignin. The reactivity of lignin was enhanced significantly for the increase of hydroxyl content and the improvement of mass transfer in chemical reaction caused by the changes of molecular structure and morphological structure. The process of MA is green and simple, and is an effective method for enhancing the reactivity of lignin. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Chemical composition measurements of the low activity waste (LAW) EPA-Series glasses

    Energy Technology Data Exchange (ETDEWEB)

    Fox, K. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Edwards, T. B. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-03-01

    In this report, the Savannah River National Laboratory provides chemical analysis results for a series of simulated low activity waste glasses provided by Pacific Northwest National Laboratory as part of an ongoing development task. The measured chemical composition data are reported and compared with the targeted values for each component for each glass. A detailed review showed no indications of errors in the preparation or measurement of the study glasses. All of the measured sums of oxides for the study glasses fell within the interval of 100.2 to 100.8 wt %, indicating recovery of all components. Comparisons of the targeted and measured chemical compositions showed that the measured values for the glasses met the targeted concentrations within 10% for those components present at more than 5 wt %.

  6. Synthesis and characterization of chemically activated carbon derived from arecanut shell

    Directory of Open Access Journals (Sweden)

    A. S. Jadhav

    2016-03-01

    Full Text Available Activated carbon (AC was prepared from areca-nut shell (AS by chemical activation using phosphoric acid (PA. Activated carbon was prepared in three batches using phosphoric acid of 50 gm, 100 gm, and 300 gm with varying impregnation ratios by weight of 1:1, 2:1 and 3:1, 4:1 each. Characterization of the prepared activated carbon was done by methylene blue number (MBN, iodine number (IN, acid adsorption test (AAT, and elemental composition. Activation was carried out at 400 C. It was found that activated carbon derived from areca-nut shell shown improved results for methylene blue number (MBN, iodine number (IN, and acid adsorption test(AAT. Thermal analysis was carried out to know the weight loss and SEM was performed to know the morphology of AC.

  7. Utilization of turkey manure as granular activated carbon: physical, chemical and adsorptive properties.

    Science.gov (United States)

    Lima, Isabel; Marshall, Wayne E

    2005-01-01

    The high availability of large quantities of turkey manure generated from turkey production makes it an attractive feedstock for carbon production. Pelletized samples of turkey litter and cake were converted to granular activated carbons (GACs) by steam activation. Water flow rate and activation time were changed to produce a range of activation conditions. The GACs were characterized for select physical (yield, surface area, bulk density, attrition), chemical (pH, surface charge) and adsorptive properties (copper ion uptake). Carbon physical and adsorptive properties were dependent on activation time and quantity of steam used as activant. Yields varied from 23% to 37%, surface area varied from 248 to 472 m(2)/g and copper ion adsorption varied from 0.72 to 1.86 mmol Cu(2+)/g carbon. Copper ion adsorption greatly exceeded the values for two commercial GACs. GACs from turkey litter and cake show considerable potential to remove metal ions from water.

  8. Chemical analysis of Greek pollen - Antioxidant, antimicrobial and proteasome activation properties

    Directory of Open Access Journals (Sweden)

    Gonos Efstathios

    2011-06-01

    Full Text Available Abstract Background Pollen is a bee-product known for its medical properties from ancient times. In our days is increasingly used as health food supplement and especially as a tonic primarily with appeal to the elderly to ameliorate the effects of ageing. In order to evaluate the chemical composition and the biological activity of Greek pollen which has never been studied before, one sample with identified botanical origin from sixteen different common plant taxa of Greece has been evaluated. Results Three different extracts of the studied sample of Greek pollen, have been tested, in whether could induce proteasome activities in human fibroblasts. The water extract was found to induce a highly proteasome activity, showing interesting antioxidant properties. Due to this activity the aqueous extract was further subjected to chemical analysis and seven flavonoids have been isolated and identified by modern spectral means. From the methanolic extract, sugars, lipid acids, phenolic acids and their esters have been also identified, which mainly participate to the biosynthetic pathway of pollen phenolics. The total phenolics were estimated with the Folin-Ciocalteau reagent and the total antioxidant activity was determined by the DPPH method while the extracts and the isolated compounds were also tested for their antimicrobial activity by the dilution technique. Conclusions The Greek pollen is rich in flavonoids and phenolic acids which indicate the observed free radical scavenging activity, the effects of pollen on human fibroblasts and the interesting antimicrobial profile.

  9. Chemical stability of a cold-active cellulase with high tolerance toward surfactants and chaotropic agent

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    Thaís V. Souza

    2016-03-01

    Full Text Available CelE1 is a cold-active endo-acting glucanase with high activity at a broad temperature range and under alkaline conditions. Here, we examined the effects of pH on the secondary and tertiary structures, net charge, and activity of CelE1. Although variation in pH showed a small effect in the enzyme structure, the activity was highly influenced at acidic conditions, while reached the optimum activity at pH 8. Furthermore, to estimate whether CelE1 could be used as detergent additives, CelE1 activity was evaluated in the presence of surfactants. Ionic and nonionic surfactants were not able to reduce CelE1 activity significantly. Therefore, CelE1 was found to be promising candidate for use as detergent additives. Finally, we reported a thermodynamic analysis based on the structural stability and the chemical unfolding/refolding process of CelE1. The results indicated that the chemical unfolding proceeds as a reversible two-state process. These data can be useful for biotechnological applications.

  10. In vitro antimicrobial activity and chemical composition of the essential oil of Foeniculum vulgare Mill.

    Science.gov (United States)

    Aprotosoaie, Ana Clara; Hăncianu, Monica; Poiată, Antonia; Tuchiluş, Cristina; Spac, A; Cioană, Oana; Gille, Elvira; Stănescu, Ursula

    2008-01-01

    In our study, four samples of volatile oil from Foeniculum vulgare, cultivated in different pedoclimatic conditions, were investigated for their antimicrobial activity and chemical composition. Organisms. Staphylococcus aureus ATCC 25923, Bacillus cereus, Pseudomonas aeruginosa, Escherichia coli ATCC 25922, Candida albicans were included in the report. Antimicrobial susceptibility tests. The comparative inhibitory activity of volatile oil samples with other antimicrobial agents was quantitative determined by minimum inhibitory concentration (MIC). Oil samples are the volatile oils extracted by steam distillation, from two ecological vegetative populations of Foeniculum vulgare. Gas chromatography coupled to mass spectrometry (GC-MS) was used to determine the chemical composition of the essential oils. All oil samples have a good activity against E. coli and S. aureus at low concentrations. Against B. cereus and P. aeruginosa these oil samples are less active. The oil samples were generally bactericidal at a concentration up to twofold or fourfold higher than the MIC value. Significantly synergic activity with amoxicillin or tetracycline showed all fennel samples against E. coli, Sarcina lutea and B. subtilis strains. Fennel oil samples have shown high activity against Candida albicans. No significant antimicrobial activity variations were observed for Foeniculum vulgare volatile oil samples obtained after two or three years cultivation period. The most important identified compounds in all samples of fennel volatile oils were trans-anethole, estragole, fenchone, limonene, alpha-pinene and gamma-terpinene.

  11. A thermodynamic framework for thermo-chemo-elastic interactions in chemically active materials

    Science.gov (United States)

    Zhang, XiaoLong; Zhong, Zheng

    2017-08-01

    In this paper, a general thermodynamic framework is developed to describe the thermo-chemo-mechanical interactions in elastic solids undergoing mechanical deformation, imbibition of diffusive chemical species, chemical reactions and heat exchanges. Fully coupled constitutive relations and evolving laws for irreversible fluxes are provided based on entropy imbalance and stoichiometry that governs reactions. The framework manifests itself with a special feature that the change of Helmholtz free energy is attributed to separate contributions of the diffusion-swelling process and chemical reaction-dilation process. Both the extent of reaction and the concentrations of diffusive species are taken as independent state variables, which describe the reaction-activated responses with underlying variation of microstructures and properties of a material in an explicit way. A specialized isothermal formulation for isotropic materials is proposed that can properly account for volumetric constraints from material incompressibility under chemo-mechanical loadings, in which inhomogeneous deformation is associated with reaction and diffusion under various kinetic time scales. This framework can be easily applied to model the transient volumetric swelling of a solid caused by imbibition of external chemical species and simultaneous chemical dilation arising from reactions between the diffusing species and the solid.

  12. Toxicity evaluation and prediction of toxic chemicals on activated sludge system.

    Science.gov (United States)

    Cai, Bijing; Xie, Li; Yang, Dianhai; Arcangeli, Jean-Pierre

    2010-05-15

    The gaps of data for evaluating toxicity of new or overloaded organic chemicals on activated sludge system resulted in the requirements for methodology of toxicity estimation. In this study, 24 aromatic chemicals typically existed in the industrial wastewater were selected and classified into three groups of benzenes, phenols and anilines. Their toxicity on activated sludge was then investigated. Two indexes of IC(50-M) and IC(50-S) were determined respectively from the respiration rates of activated sludge with different toxicant concentration at mid-term (24h) and short-term (30min) time intervals. Experimental results showed that the group of benzenes was the most toxic, followed by the groups of phenols and anilines. The values of IC(50-M) of the tested chemicals were higher than those of IC(50-S). In addition, quantitative structure-activity relationships (QSARs) models developed from IC(50-M) were more stable and accurate than those of IC(50-S). The multiple linear models based on molecular descriptors and K(ow) presented better reliability than single linear models based on K(ow). Among these molecular descriptors, E(lumo) was the most important impact factor for evaluation of mid-term toxicity. Copyright (c) 2009 Elsevier B.V. All rights reserved.

  13. Chemical composition and lipoxygenase activity in soybeans (Glycine max L. Merr.) submitted to gamma irradiation

    Science.gov (United States)

    Barros, Érica Amanda de; Broetto, Fernando; Bressan, Dayanne F.; Sartori, Maria M. P.; Costa, Vladimir E.

    2014-05-01

    Soybeans are an important food due to their functional and nutritional characteristics. However, consumption by western populations is limited by the astringent taste of soybeans and their derivatives which results from the action of lipoxygenase, an enzyme activated during product processing. The aim of this study was to evaluate the effect of gamma irradiation on the chemical composition and specific activity of lipoxygenase in different soybean cultivars. Soybeans were stored in plastic bags and irradiated with doses of 2.5, 5 and 10 kGy. The chemical composition (moisture, protein, lipids, ashes, crude fiber, and carbohydrates) and lipoxygenase specific activity were determined for each sample. Gamma irradiation induced a small increase of protein and lipid content in some soybean cultivars, which did not exceed the highest content of 5% and 26%, respectively, when compared to control. Lipoxygenase specific activity decreased in the three cultivars with increasing gamma irradiation dose. In conclusion, the gamma irradiation doses used are suitable to inactivate part of lipoxygenase while not causing expressive changes in the chemical composition of the cultivars studied.

  14. Activity Enhancement Based on the Chemical Equilibrium of Multiple-Subunit Nitrile Hydratase from Bordetella petrii.

    Science.gov (United States)

    Liu, Yi; Liu, Ping; Lin, Lu; Zhao, Yueqin; Zhong, Wenjuan; Wu, Lunjie; Zhou, Zhemin; Sun, Weifeng

    2016-09-01

    The maturation mechanism of nitrile hydratase (NHase) of Pseudomonas putida NRRL-18668 was discovered and named as "self-subunit swapping." Since the NHase of Bordetella petrii DSM 12804 is similar to that of P. putida, the NHase maturation of B. petrii is proposed to be the same as that of P. putida. However, there is no further information on the application of NHase according to these findings. We successfully rapidly purified NHase and its activator through affinity his tag, and found that the cell extracts of NHase possessed multiple types of protein ingredients including α, β, α2β2, and α(P14K)2 who were in a state of chemical equilibrium. Furthermore, the activity was significantly enhanced through adding extra α(P14K)2 to the cell extracts of NHase according to the chemical equilibrium. Our findings are useful for the activity enhancement of multiple-subunit enzyme and for the first time significantly increased the NHase activity according to the chemical equilibrium.

  15. Chemical Structure-Biological Activity Models for Pharmacophores’ 3D-Interactions

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    Mihai V. Putz

    2016-07-01

    Full Text Available Within medicinal chemistry nowadays, the so-called pharmaco-dynamics seeks for qualitative (for understanding and quantitative (for predicting mechanisms/models by which given chemical structure or series of congeners actively act on biological sites either by focused interaction/therapy or by diffuse/hazardous influence. To this aim, the present review exposes three of the fertile directions in approaching the biological activity by chemical structural causes: the special computing trace of the algebraic structure-activity relationship (SPECTRAL-SAR offering the full analytical counterpart for multi-variate computational regression, the minimal topological difference (MTD as the revived precursor for comparative molecular field analyses (CoMFA and comparative molecular similarity indices analysis (CoMSIA; all of these methods and algorithms were presented, discussed and exemplified on relevant chemical medicinal systems as proton pump inhibitors belonging to the 4-indolyl,2-guanidinothiazole class of derivatives blocking the acid secretion from parietal cells in the stomach, the 1-[(2-hydroxyethoxy-methyl]-6-(phenylthiothymine congeners’ (HEPT ligands antiviral activity against Human Immunodeficiency Virus of first type (HIV-1 and new pharmacophores in treating severe genetic disorders (like depression and psychosis, respectively, all involving 3D pharmacophore interactions.

  16. Preparation and characterization of activated carbon from pistachio nut shells via microwave-induced chemical activation

    International Nuclear Information System (INIS)

    Foo, K.Y.; Hameed, B.H.

    2011-01-01

    In this work, pistachio nut shell, a biomass residue abundantly available from the pistachio nut processing industries, was utilized as a feedstock for the preparation of activated carbon (PSAC) via microwave assisted KOH activation. The activation step was performed at the microwave input power of 600 W and irradiation time of 7 min. The porosity, functional and surface chemistry were featured by means of low temperature nitrogen adsorption, scanning electron microscopy and Fourier transform infrared spectroscopy. Result showed that the BET surface area, Langmuir surface area, and total pore volume of PSAC were 700.53 m 2 g -1 , 1038.78 m 2 g -1 and 0.375 m 3 g -1 , respectively. The adsorptive property of PSAC was tested using methylene blue dye as the targeted adsorbate. Equilibrium data was best fitted by the Langmuir isotherm model, showing a monolayer adsorption capacity of 296.57 mg g -1 . The study revealed the potentiality of microwave-induced activation as a viable activation method. -- Highlights: → Pistachio nut shell activated carbon (PSAC) was prepared via microwave assisted KOH activation. → The activation step was performed at the microwave input power of 600 W and irradiation time of 7 min. → BET surface area of PSAC was 700.53 m 2 /g. → Monolayer adsorption capacity of PSAC for MB was 296.57 mg/g.

  17. Preparation and characterization of activated carbon from pistachio nut shells via microwave-induced chemical activation

    Energy Technology Data Exchange (ETDEWEB)

    Foo, K. Y. [School of Chemical Engineering, Engineering Campus, Universiti Sains Malaysia, 14300 Nibong Tebal, Penang (Malaysia); Hameed, B.H., E-mail: chbassim@eng.usm.my [School of Chemical Engineering, Engineering Campus, Universiti Sains Malaysia, 14300 Nibong Tebal, Penang (Malaysia)

    2011-07-15

    In this work, pistachio nut shell, a biomass residue abundantly available from the pistachio nut processing industries, was utilized as a feedstock for the preparation of activated carbon (PSAC) via microwave assisted KOH activation. The activation step was performed at the microwave input power of 600 W and irradiation time of 7 min. The porosity, functional and surface chemistry were featured by means of low temperature nitrogen adsorption, scanning electron microscopy and Fourier transform infrared spectroscopy. Result showed that the BET surface area, Langmuir surface area, and total pore volume of PSAC were 700.53 m{sup 2} g{sup -1}, 1038.78 m{sup 2} g{sup -1} and 0.375 m{sup 3} g{sup -1}, respectively. The adsorptive property of PSAC was tested using methylene blue dye as the targeted adsorbate. Equilibrium data was best fitted by the Langmuir isotherm model, showing a monolayer adsorption capacity of 296.57 mg g{sup -1}. The study revealed the potentiality of microwave-induced activation as a viable activation method. -- Highlights: {yields} Pistachio nut shell activated carbon (PSAC) was prepared via microwave assisted KOH activation. {yields} The activation step was performed at the microwave input power of 600 W and irradiation time of 7 min. {yields} BET surface area of PSAC was 700.53 m{sup 2}/g. {yields} Monolayer adsorption capacity of PSAC for MB was 296.57 mg/g.

  18. [Advances in research of chemical constituents and pharmacological activities of common used spices].

    Science.gov (United States)

    Sun, Chao-nan; Zhu, Yuan; Xu, Xi-ming; Yu, Jiang-nan

    2014-11-01

    Spices have enjoyed a long history and a worldwide application. Of particular interest is the pharmaceutical value of spices in addition to its basic seasoning function in cooking. Concretely, equipped with complex chemical compositions, spices are of significant importance in pharmacologic actions, like antioxidant, antibacterial, antitumor, as well as therapeutical effects in gastrointestinal disorders and cardiovascular disease. Although increasing evidences in support of its distinct role in the medical field has recently reported, little information is available for substantive, thorough and sophisticated researches on its chemical constituents and pharmacological activities, especially mechanism of these actions. Therefore, in popular wave of studies directed at a single spice, this review presents systematic studies on the chemical constituents and pharmacological activities associated with common used spices, together with current typical individual studies on functional mechanism, in order to pave the way for the exploitation and development of new medicines derived from the chemical compounds of spice (such as, piperine, curcumin, geniposide, cinnamaldehyde, cinnamic acid, linalool, estragole, perillaldehyde, syringic acid, crocin).

  19. Chemical Composition and Antioxidant Activities of Three Polysaccharide Fractions from Pine Cones

    Directory of Open Access Journals (Sweden)

    Pu Wang

    2012-11-01

    Full Text Available The traditional method of gas chromatography-mass spectrometry for monosaccharide component analysis with pretreatment of acetylation is described with slight modifications and verified in detail in this paper. It was then successfully applied to the quantitative analysis of component monosaccharides in polysaccharides extracted from the pine cones. The results demonstrated that the three pine cone polysaccharides all consisted of ribose, rhamnose, arabinose, xylose, mannose, glucose and galactose in different molar ratios. According to the recovery experiment, the described method was proved accurate and practical for the analysis of pine cone polysaccharides, meeting the need in the field of chemical analysis of Pinus plants. Furthermore; the chemical characteristics, such as neutral sugar, uronic acids, amino acids, molecular weights, and antioxidant activities of the polysaccharides were investigated by chemical and instrumental methods. The results showed that the chemical compositions of the polysaccharides differed from each other, especially in the content of neutral sugar and uronic acid. In the antioxidant assays, the polysaccharide fractions exhibited effective scavenging activities on ABTS radical and hydroxyl radical, with their antioxidant capabilities decreasing in the order of PKP > PAP > PSP. Therefore, although the polysaccharide fractions had little effect on superoxide radical scavenging, they still have potential to be developed as natural antioxidant agents in functional foods or medicine.

  20. Offgas Analysis and Pyrolysis Mechanism of Activated Carbon from Bamboo Sawdust by Chemical Activation With KOH

    Institute of Scientific and Technical Information of China (English)

    TIAN Yong; LIU Ping; WANG Xiufang; ZHONG Guoying; CHEN Guanke

    2011-01-01

    Bamboo sawdust was used as the precursor for the multipurpose use of waste.Offgases released during the activation process of bamboo by KOH were investigated quantitatively and qualitatively by a gas analyzer. TG/DTG curves during the pyrolysis process with different impregnation weight ratios (KOH to bamboo) were obtained by a thermogravimetric analyzer. Pyrolysis mechanism of bamboo was proposed. The results showed that the offgases were composed of CO, NO,SO2 and hydrocarbon with the concentration of 1 372, 37, 86, 215 mg/L, respectively. Thermogravimetric analysis indicated that the pyrolytic process mainly experienced two steps. The first was the low temperature activation step (lower than 300 ℃), which was the pre-activation and induction period.The second was the high temperature activation step(higher than 550 ℃), which was a radial activation followed by pore production. The second process was the key to control the pore distribution of the final product.

  1. Chemical composition and antifungal activity of thyme (Thymus vulgaris essential oil

    Directory of Open Access Journals (Sweden)

    S. Farsaraei*

    2017-11-01

    Full Text Available Background and objectives: The antifungal activity of the essential oils and their constituents against some phytopathogenic fungi has been reported. Thymus vulgaris (Lamiaceae is one of the Thymus species.  A large number of studies have concerned the chemical compositions and antifungal activity of thyme’s oil. In order to reduce the use of synthetic fungicides, recently considerable attention has been given to search for naturally occurring compounds. The aim of the present work was to determine the chemical composition and antifungal activity of T. vulgaris oil cultivated in Iran. Methods: The essential oil from aerial parts of the plant at full flowering stage was subjected to hydrodistillation and chemical compounds were analyzed by GC/GC-MS. The in vitro antifungal activity against three phytopathogenic fungi (Drechslera spicifera, Fusarium oxysporum f.sp. ciceris and Macrophomina phaseolinaby of the oil was evaluated by agar dilution method. The data were subjected to ANOVA according to the SPSS 21 software. Results: Totally 45 compounds representing 96.75% of the oil were found. Thymol (36.81% and ρ-cymene (30.90% were the main components of thyme oil. According to the results, the antifungal activity of the oil increased with a rising in concentration. All of the tested fungi growth was completely inhibited on 1600 µL/L. In this study fungicidal activity was only observed on F. oxysporum and D. spicifera at concentrations higher than 800 µL/L.  Conclusion: The antifungal activity of T. vulgaris essential oil could be probably due to the high concentration of oxygenated monoterpenes (thymol and monoterpene hydrocarbons (ρ-cymene.

  2. Atmospheric-pressure electric discharge as an instrument of chemical activation of water solutions

    Science.gov (United States)

    Rybkin, V. V.; Shutov, D. A.

    2017-11-01

    Results of experimental studies and numerical simulations of physicochemical characteristics of plasmas generated in different types of atmospheric-pressure discharges (pulsed streamer corona, gliding electric arc, dielectric barrier discharge, glow-discharge electrolysis, diaphragmatic discharge, and dc glow discharge) used to initiate various chemical processes in water solutions are analyzed. Typical reactor designs are considered. Data on the power supply characteristics, plasma electron parameters, gas temperatures, and densities of active particles in different types of discharges excited in different gases and their dependences on the external parameters of discharges are presented. The chemical composition of active particles formed in water is described. Possible mechanisms of production and loss of plasma particles are discussed.

  3. Chemical composition and antimicrobial activity of the essential oils of Pinus pinaster

    Directory of Open Access Journals (Sweden)

    Nouara Ait Mimoune

    2013-08-01

    Full Text Available Objective: To investigate the antimicrobial activity and chemical composition of essential oils of Pinus pinaster. Methods: Essential oils were extracted from the needles by hydrodistillation. The chemical composition of the obtained essential oils was analyzed using GC-MS technique. The antimicrobial potential has been tested against six microorganisms performing the disc diffusion assay. Results: Twenty-three components have been identified. β-caryophyllene (30.9% and β-selinene (13.45% were predominant compounds. The essential oil exhibited a moderate activity against Staphylococcus aureus, Bacillus subtilis and Escherichia coli, but did not affect the growth of Erwinia amylovora. Aspergillus flavus and Aspergillus niger were not inhibited by maritime pine essential oils. Conclusions: The essential oils from Pinus pinaster can be used as an antibacterial agent.

  4. Plant Sterols: Chemical and Enzymatic Structural Modifications and Effects on Their Cholesterol-Lowering Activity.

    Science.gov (United States)

    He, Wen-Sen; Zhu, Hanyue; Chen, Zhen-Yu

    2018-03-28

    Plant sterols have attracted increasing attention due to their excellent cholesterol-lowering activity. However, free plant sterols have some characteristics of low oil solubility, water insolubility, high melting point, and low bioavailability, which greatly limit their application in foods. Numerous studies have been undertaken to modify their chemical structures to improve their chemical and physical properties in meeting the needs of various applications. The present review is to summarize the literature and update the progress on structural modifications of plant sterols in the following aspects: (i) synthesis of plant sterol esters by esterification and transesterification with hydrophobic fatty acids and triacylglycerols to improve their oil solubility, (ii) synthesis of plant sterol derivatives by coupling with various hydrophilic moieties to enhance their water solubility, and (iii) mechanisms by which plant sterols reduce plasma cholesterol and the effect of structural modifications on plasma cholesterol-lowering activity of plant sterols.

  5. Chemical Composition, Antioxidant, and Antimicrobial Activities of Lichen Umbilicaria cylindrica (L. Delise (Umbilicariaceae

    Directory of Open Access Journals (Sweden)

    Nedeljko T. Manojlovic

    2012-01-01

    Full Text Available The phytochemical analysis of methanol and chloroform extracts of Umbilicaria cylindrica was determined by HPLC-UV method. The predominant phenolic compound in both extracts was depsidone, salazinic acid (1. Besides salazinic acid, the tested extracts of U. cylindrica contain norstictic acid (2, methyl-β-orcinol carboxylate (3, ethyl haematommate (4, atranorin (5, and usnic acid (6, in different amounts and relations. The lichen extracts showed comparable and strong antioxidant activity, exhibited higher DPPH and hydroxyl radical scavengings, chelating activity, and inhibitory activity towards lipid peroxidation. The lichen extracts demonstrated important antimicrobial activity against eight strains with MIC values from 15.62 to 62.50 μg/mL. This is the first report of the detail chemical composition and antioxidant activity of the lichen Umbilicaria cylindrica, and the results suggest that this lichen can be used as a new source of the natural antioxidants and the substances with antimicrobial features.

  6. Antimicrobial activity of Algerian propolis in foodborne pathogens and its quantitative chemical composition

    Directory of Open Access Journals (Sweden)

    Neila Nedji

    2014-12-01

    Full Text Available Objective: To evaluate the antimicrobial activity of propolis samples collected from different regions of Algeria and their chemical composition. Methods: The antibacterial activity of ethanolic extract of Algerian propolis against Bacillus cereus (IPA, Staphylococcus aureus (ATCC25923R, Escherichia coli (ATCC25922 and Pseudomonas aeruginosa (ATCC27893R was evaluated by the disc diffusion method and determined as an equivalent of the inhibition zones diameters after incubation of the cultures at 37 °C for 24 h. The investigation of the polyphenol and flavonoid contents was done spectrophotometrically. Results: The ethanolic extract of Algerian propolis samples inhibited the growth of all examined microorganisms with the highest antimicrobial activity against the Gram-positive bacteria. Polyphenol and flavonoids contents were variable, depending on the propolis samples and a positive correlation between antimicrobial activity and chemical composition was observed. Conclusions: Antimicrobial activity, polyphenol and flavonoid contents were variable, depending on the propolis sample. The strong antimicrobial activity of Algerian propolis may be due to high total phenolic and flavonoid contents and this study suggests potential use of propolis in foods.

  7. Biological activity and chemical profile of Lavatera thuringiaca L. extracts obtained by different extraction approaches.

    Science.gov (United States)

    Mašković, Pavle Z; Veličković, Vesna; Đurović, Saša; Zeković, Zoran; Radojković, Marija; Cvetanović, Aleksandra; Švarc-Gajić, Jaroslava; Mitić, Milan; Vujić, Jelena

    2018-01-01

    Lavatera thuringiaca L. is herbaceous perennial plant from Malvaceae family, which is known for its biological activity and richness in polyphenolic compounds. Despite this, the information regarding the biological activity and chemical profile is still insufficient. Aim of this study was to investigate biological potential and chemical profile of Lavatera thuringiaca L., as well as influence of applied extraction technique on them. Two conventional and four non-conventional extraction techniques were applied in order to obtain extracts rich in bioactive compound. Extracts were further tested for total phenolics, flavonoids, condensed tannins, gallotannins and anthocyanins contents using spectrophotometric assays. Polyphenolic profile was established using HPLC-DAD analysis. Biological activity was investigated regarding antioxidant, cytotoxic and antibacterial activities. Four antioxidant assays were applied as well as three different cell lines for cytotoxic and fifteen bacterial strain for antibacterial activity. Results showed that subcritical water extraction (SCW) dominated over the other extraction techniques, where SCW extract exhibited the highest biological activity. Study indicates that plant Lavatera thuringiaca L. may be used as a potential source of biologically compounds. Copyright © 2017 Elsevier GmbH. All rights reserved.

  8. Chemical Composition, Antioxidant and Anticholinesterase Activities of the Essential oil of Origanum rotundifolium Boiss. from Turkey

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    Hilal Özbek

    2017-09-01

    Full Text Available The essential oil was obtained by hydrodistillation from the aerial parts of Origanum rotundifolium Boiss. Its chemical content and composition were analyzed by using a gas chromatography (GC-FID and gas chromatography-mass spectrometry (GC-MS. Total phenolic content of the essential oil was determined as 132.39 µg gallic acid equivalent by Folin–Ciocalteu’s method and the major component was identified as carvacrol (56.8 % along with p-cymene (13.1 %, (Z- b -ocimene (5.4 %, b -caryophyllene (3.9 %, borneol (3.4 % and thymol (3.2 %. After chemical characterization, the essential oil was evaluated for its antioxidant activity by DPPH free radical, superoxide anion radical and hydrogen peroxide scavenging activities as well as ferrous ion-chelating power test, ABTS radical cation decolorization assay and ferric thiocyanate methods. Besides antioxidant activity, acetylcholinesterase and butyrylcholinesterase inhibitory activities of the essential oil were also evaluated by Ellman’s method. It demonstrated inhibitory activities on AChE and BuChE, key enzymes in the pathogenesis of Alzheimer’s disease (AD, in addition to significant antioxidant activity.

  9. Chemical variability and antioxidant activity of the leaves of chosen highbush blueberry (Vaccinium corymbosum L.) cultivars

    OpenAIRE

    Janiuk M.; Najda A.; Gantner M.; Błażewicz-Woźniak M.

    2013-01-01

    The paper deals with the chemical composition and antioxidant activity of aqueous extracts from leaves of two highbush blueberry varieties: ‘Bluecrop’ and ‘Northland’. The study revealed differences in the content of the analyzed components. Leaves of cv. ‘Bluecrop’ were characterized by a higher content of chlorophyll, flavonoids and anthocyanins, while the leaves of cv. ‘Northland’ contained more reducing sugars and total phenolic acids, tannins, and essential oils. Capacity of neutrali...

  10. Chemical Composition and Biological Activities of Fragrant Mexican Copal (Bursera spp.).

    Science.gov (United States)

    Gigliarelli, Giulia; Becerra, Judith X; Curini, Massimo; Marcotullio, Maria Carla

    2015-12-12

    Copal is the Spanish word used to describe aromatic resins from several genera of plants. Mexican copal derives from several Bursera spp., Protium copal, some Pinus spp. (e.g., P. pseudostrobus) and a few Fabaceae spp. It has been used for centuries as incense for religious ceremonies, as a food preservative, and as a treatment for several illnesses. The aim of this review is to analyze the chemical composition and biological activity of commercial Mexican Bursera copal.

  11. Chemical Composition and Biological Activities of Fragrant Mexican Copal (Bursera spp.

    Directory of Open Access Journals (Sweden)

    Giulia Gigliarelli

    2015-12-01

    Full Text Available Copal is the Spanish word used to describe aromatic resins from several genera of plants. Mexican copal derives from several Bursera spp., Protium copal, some Pinus spp. (e.g., P. pseudostrobus and a few Fabaceae spp. It has been used for centuries as incense for religious ceremonies, as a food preservative, and as a treatment for several illnesses. The aim of this review is to analyze the chemical composition and biological activity of commercial Mexican Bursera copal.

  12. Antioxidant Activity of a Geopropolis from Northeast Brazil: Chemical Characterization and Likely Botanical Origin

    OpenAIRE

    Ferreira, Joselena M.; Fernandes-Silva, Caroline C.; Salatino, Antonio; Message, Dejair; Negri, Giuseppina

    2017-01-01

    Geopropolis is a product containing wax, plant resin, and soil particles. It is elaborated by stingless bees of tribe Meliponini. Methanol extracts of sample of geopropolis produced by Scaptotrigona postica (“mandaguari”) in the state of Rio Grande do Norte (RN, northeast Brazil) were analyzed for the determination of standard parameters (total phenols, total flavonoids, and radical scavenging activity) and chemical characterization by HPLC-DAD-MS/MS analysis. The sample analyzed has high con...

  13. Antimicrobial Activity and Chemical Composition of the Essential Oils of Portuguese Foeniculum vulgare Fruits

    OpenAIRE

    Mota, Ana; Martins, M. Rosário; Arantes, Silvia; Lopes, Violeta; Bettencourt, Eliseu; Pombal, Sofia; Gomes, Arlindo; Silva, Lúcia

    2015-01-01

    The aim of this study was to investigate the chemical composition and antimicrobial activity of essential oils obtained by hydrodistillation from fruits of six fennel accessions collected from wild populations occurring in the centre and south of Portugal. Composition of essential oils was established by Gas Chromatography-Flame Ionization Detector (GC-FID) and Gas Chromatography-Mass Spectrometry (GC-MS) analysis. The obtained yields of the essential oils were found to vary greatly ...

  14. Chemical Composition, Antimicrobial and Antioxidant Activities of Essential Oils from Organically Cultivated Fennel Cultivars

    OpenAIRE

    Shahat, Abdelaaty A.; Ibrahim, Abeer Y.; Hendawy, Saber F.; Omer, Elsayed A.; Hammouda, Faiza M.; Abdel-Rahman, Fawzia H.; Saleh, Mahmoud A.

    2011-01-01

    Essential oils of the fruits of three organically grown cultivars of Egyptian fennel (Foeniculum vulgare var. azoricum, Foeniculum vulgare var. dulce and Foeniculum vulgare var. vulgare) were examined for their chemical constituents, antimicrobial and antioxidant activities. Gas chromatography/mass spectrometry analysis of the essential oils revealed the presence of 18 major monoterpenoids in all three cultivars but their percentage in each oil were greatly different. trans-Anethole, estragol...

  15. Physico-chemical studies and evaluation of diuretic activity of Cucurbita maxima

    Directory of Open Access Journals (Sweden)

    Venkattapuram Sampath Saravanan

    2012-12-01

    Full Text Available In this study physico-chemical nature and diuretic activity was evaluated to establish the purity and diuretic activity by comparing with the standard acetazolamide. Pulp of Cucurbita maxima is a common cost effective Indian dish, rich in nutrients. Physico-chemical parameters like ash values, extractive values and loss on drying were performed to find the purity. The hydro-alcoholic extract was prepared by extracting the powder in soxhlet apparatus for 36 hrs. The laboratory qualitative analysis was done and constituents like carbohydrates, proteins, lipids, flavonoids, alkaloids and vitamin C were found. The two doses of extract (150 and 300 mg/kg were given to the rats. Group I served as control, Group II served as standard and Group III and IV served as test. Electrolytes and urine volume was measured after 5 hrs of treatment and the same was compared with the control and the standard drug acetazolamide. Physico-chemical parameters were in the limit and the extract shows significant (p<0.01 diuretic activity at the dose of 300 mg/kg when compared with control.

  16. Chemical composition and biological activity of ripe pumpkin fruits (Cucurbita pepo L.) cultivated in Egyptian habitats.

    Science.gov (United States)

    Badr, Sherif E A; Shaaban, Mohamed; Elkholy, Yehya M; Helal, Maher H; Hamza, Akila S; Masoud, Mohamed S; El Safty, Mounir M

    2011-09-01

    The chemical composition and biological activity of three parts (rind, flesh and seeds) of pumpkin fruits (Cucurbita pepo L.) cultivated in Egypt were studied. Chemical analysis of fibre, protein, β-carotene, carbohydrates, minerals and fatty acids present in the rind, flesh, seeds and defatted seeds meal was conducted. Chemical, GC-MS and biological assays of organic extracts of the main fruit parts, rind and flesh established their unique constituents. Chromatographic purification of the extracts afforded triglyceride fatty acid mixture (1), tetrahydro-thiophene (2), linoleic acid (3), calotropoleanly ester (4), cholesterol (5) and 13(18)-oleanen-3-ol (6). GC-MS analysis of the extract's unpolar fraction revealed the existence of dodecane and tetradecane. Structures of the isolated compounds (1-6) were confirmed by NMR and EI-MS spectrometry. Antimicrobial, antiviral and antitumour activities of the fruit parts were discussed. The promising combined extract of rind and flesh was biologically studied for microbial and cytotoxic activities in comparison with the whole isolated components.

  17. Synthesis of sulfonated porous carbon nanospheres solid acid by a facile chemical activation route

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Binbin, E-mail: changbinbin806@163.com; Guo, Yanzhen; Yin, Hang; Zhang, Shouren; Yang, Baocheng, E-mail: baochengyang@yahoo.com

    2015-01-15

    Generally, porous carbon nanospheres materials are usually prepared via a template method, which is a multi-steps and high-cost strategy. Here, we reported a porous carbon nanosphere solid acid with high surface area and superior porosity, as well as uniform nanospheical morphology, which prepared by a facile chemical activation with ZnCl{sub 2} using resorcinol-formaldehyde (RF) resins spheres as precursor. The activation of RF resins spheres by ZnCl{sub 2} at 400 °C brought high surface area and large volume, and simultaneously retained numerous oxygen-containing and hydrogen-containing groups due to the relatively low processing temperature. The presence of these functional groups is favorable for the modification of –SO{sub 3}H groups by a followed sulfonation treating with sulphuric acid and organic sulfonic acid. The results of N{sub 2} adsorption–desorption and electron microscopy clearly showed the preservation of porous structure and nanospherical morphology. Infrared spectra certified the variation of surface functional groups after activation and the successful modification of –SO{sub 3}H groups after sulfonation. The acidities of catalysts were estimated by an indirect titration method and the modified amount of –SO{sub 3}H groups were examined by energy dispersive spectra. The results suggested sulfonated porous carbon nanospheres catalysts possessed high acidities and –SO{sub 3}H densities, which endowed their significantly catalytic activities for biodiesel production. Furthermore, their excellent stability and recycling property were also demonstrated by five consecutive cycles. - Graphical abstract: Sulfonated porous carbon nanospheres with high surface area and superior catalytic performance were prepared by a facile chemical activation route. - Highlights: • Porous carbon spheres solid acid prepared by a facile chemical activation. • It owns high surface area, superior porosity and uniform spherical morphology. • It possesses

  18. Preparation of porous bio-char and activated carbon from rice husk by leaching ash and chemical activation.

    Science.gov (United States)

    Ahiduzzaman, Md; Sadrul Islam, A K M

    2016-01-01

    Preparation porous bio-char and activated carbon from rice husk char study has been conducted in this study. Rice husk char contains high amount silica that retards the porousness of bio-char. Porousness of rice husk char could be enhanced by removing the silica from char and applying heat at high temperature. Furthermore, the char is activated by using chemical activation under high temperature. In this study no inert media is used. The study is conducted at low oxygen environment by applying biomass for consuming oxygen inside reactor and double crucible method (one crucible inside another) is applied to prevent intrusion of oxygen into the char. The study results shows that porous carbon is prepared successfully without using any inert media. The adsorption capacity of material increased due to removal of silica and due to the activation with zinc chloride compared to using raw rice husk char. The surface area of porous carbon and activated carbon are found to be 28, 331 and 645 m(2) g(-1) for raw rice husk char, silica removed rice husk char and zinc chloride activated rice husk char, respectively. It is concluded from this study that porous bio-char and activated carbon could be prepared in normal environmental conditions instead of inert media. This study shows a method and possibility of activated carbon from agro-waste, and it could be scaled up for commercial production.

  19. The role of neutron activation analysis at The Dow Chemical Company

    International Nuclear Information System (INIS)

    Rigot, W.L.; Buchmann, M.E.; Quinn, T.J.; Romick, J.D.; Yusuf, S.O.

    2000-01-01

    The role of neutron activation analysis (NAA) at The Dow Chemical Company has not changed significantly since the first operations, which were conducted in July, 1967. That role is threefold; provide results with appropriate precision, accuracy and sensitivity; provide results in a timely manner; and provide results for a reasonable cost. What has changed, are the requirements for satisfying each of the three components of the role. In a business-focused environment, analyses need to be performed faster with better sensitivity and/or precision and be more cost efficient. In order to meet these requirements, operations at The Dow TRIGA Research Reactor are devoted to NAA activities. (author)

  20. Essential Oils’ Chemical Characterization and Investigation of Some Biological Activities: A Critical Review

    Science.gov (United States)

    Dhifi, Wissal; Bellili, Sana; Jazi, Sabrine; Bahloul, Nada; Mnif, Wissem

    2016-01-01

    This review covers literature data summarizing, on one hand, the chemistry of essential oils and, on the other hand, their most important activities. Essential oils, which are complex mixtures of volatile compounds particularly abundant in aromatic plants, are mainly composed of terpenes biogenerated by the mevalonate pathway. These volatile molecules include monoterpenes (hydrocarbon and oxygenated monoterpens), and also sesquiterpenes (hydrocarbon and oxygenated sesquiterpens). Furthermore, they contain phenolic compounds, which are derived via the shikimate pathway. Thanks to their chemical composition, essential oils possess numerous biological activities (antioxidant, anti-inflammatory, antimicrobial, etc…) of great interest in food and cosmetic industries, as well as in the human health field. PMID:28930135

  1. In Situ Earthworm Breeding to Improve Soil Aggregation, Chemical Properties, and Enzyme Activity in Papayas

    Directory of Open Access Journals (Sweden)

    Huimin Xiang

    2018-04-01

    Full Text Available The long-term use of mineral fertilizers has decreased the soil fertility in papaya (Carica papaya L. orchards in South China. In situ earthworm breeding is a new sustainable practice for improving soil fertility. A field experiment was conducted to compare the effects of four treatments consisting of the control (C, chemical fertilizer (F, compost (O, and in situ earthworm breeding (E on soil physico-chemical properties and soil enzyme activity in a papaya orchard. The results showed that soil chemical properties, such as pH, soil organic matter (SOM, total nitrogen (TN, available nitrogen (AN, and total phosphorus (TP were significantly improved with the E treatment but declined with the F treatment. On 31 October 2008, the SOM and TN with the O and E treatments were increased by 26.3% and 15.1%, respectively, and by 32.5% and 20.6% compared with the F treatment. Furthermore, the O and E treatments significantly increased the activity of soil urease and sucrase. Over the whole growing season, soil urease activity was 34.4%~40.4% and 51.1%~58.7% higher with the O and E treatments, respectively, than that with the C treatment. Additionally, the activity of soil sucrase with the E treatment was always the greatest of the four treatments, whereas the F treatment decreased soil catalase activity. On 11 June 2008 and 3 July 2008, the activity of soil catalase with the F treatment was decreased by 19.4% and 32.0% compared with C. Soil bulk density with the four treatments was in the order of O ≤ E < F < C. The O- and E-treated soil bulk density was significantly lower than that of the F-treated soil. Soil porosity was in the order of C < F < E < O. Soil porosity with the O and E treatments was 6.0% and 4.7% higher, respectively, than that with the F treatment. Meanwhile, the chemical fertilizer applications significantly influenced the mean weight diameter (MWD of the aggregate and proportion of different size aggregate fractions. The E treatment

  2. Chemical Composition and Biological Activities of Mono- and Heterofloral Bee Pollen of Different Geographical Origins

    Directory of Open Access Journals (Sweden)

    Jucilene Silva Araújo

    2017-04-01

    Full Text Available Recent research shows variations in pollen chemical constituents and, consequently, in their therapeutic properties. Mono and multifloral bee pollen extracts were investigated for antioxidant and enzyme inhibitory activity properties, phenolic compounds and fatty acid composition. Generally, Eucalyptus spp. and multifloral extracts exhibited potent inhibitory activity against α-amylase, acetylcholinesterase, tyrosinase, lipoxygenase, lipase and hyaluronidase. On the other hand, Miconia spp. demonstrated higher antihemolytic activity. Cocos nucifera and Miconia spp. extracts exhibited important antioxidant properties in the different assays (ABTS, DPPH, β-carotene/linoleic acid and reducing power. Moreover, these extracts had greater amounts of total phenols and flavonoids in comparison to others. The increase in antioxidant activity (decrease in EC50 values was accompanied by an increase in the amount of total phenols in the extracts. The pollen extracts contained linoleic acid and α-linolenic acid as major fatty acids, followed by palmitic acid, and oleic acid. In this study, differences were observed in both chemical constituents and biological activities of the samples related to the geographical and botanical origin of bee pollen.

  3. Chemical characterization and antioxidant activity of Eryngium campestre L., Apiaceae from Kosovo

    Directory of Open Access Journals (Sweden)

    Flurim Nebija

    2009-12-01

    Full Text Available This study is outlined to define the chemical composition and in vitro antioxidant activity of the extracts of aerial part and root of Eryngium campestre L. (Apiaceae from Kosovo. Analysis of the chemical composition include determination of total ash, ash insoluble in hydrochloric acid, loss on drying and the content of water extract, as well as determination of flavonoids in aerial part and hemolytic activity of the root. The mineral composition (Zn, Fe, Cu, Mn, Ni, K, Co, Pb, Cd and Cr in aerial parts and root has been studied using atomic absorption spectroscopy (AAS and ETAAS. Different part of E. campestre accumulate different amounts of investigated minerals. Antioxidant activity was determined by four various testing systems: DPPH assay, inhibition of production of hydroxyl radical, β-carotenebleaching assay, and inhibition of lipid peroxidation (TBA test. In DPPH system, ethanol extract of root of E. campestre exhibited higher radical-scavenging activity (IC50 = 0.72 mg ml-1 compared to the extract of the aerial part (IC50 = 1.14 mg ml-1. On the other hand, aerial part ethanol extract has exhibited stronger inhibition capacity on the production of hydroxyl radical in deoxyribose system than the root extract (50% and 45%, respectively. However, both ethanol extracts of E. campestre exhibited low antioxidant activity in β-carotenebleaching assay as well as, low capacity for inhibition of spontaneous lipid peroxidation in rat liver homogenate.

  4. Pachira glabra Pasq. essential oil: chemical constituents, antimicrobial and insecticidal activities.

    Science.gov (United States)

    Lawal, Oladipupo A; Ogunwande, Isiaka A; Salvador, Atinuke F; Sanni, Adetayo A; Opoku, Andy R

    2014-01-01

    The chemical composition of essential oil obtained by hydrodistillation of the leaves of Pachira glabra Pasq., (PgEO) has been studied by Gas Chromatography (GC) and Gas Chromatography coupled with Mass Spectrometry (GC/MS). Thirty three constituents representing 98.4% of total contents were identified from the essential oil. The major constituents of oil were limonene (23.2%), β-caryophyllene (14.5%), phtyol (8.5%) and β-bisabolene (6.3%). The antimicrobial activity of the PgEO was evaluated against a panel of ten bacteria and three fungal strain using agar diffusion and broth microdilution methods. Results have shown that the PgEO exhibited moderate to strong antimicrobial activity against the tested microorganisms except Citrobacter youagae, Micrococcus spp. and Proteus spp. The activity zones of inhibition (ZI) and minimum inhibitory concentrations (MIC) ranged between 13.7 mm-24.0 mm and 0.3 mg/mL-2.5 mg/mL, respectively. The insecticidal activity of PgEO was assayed against the adult Sitophilus zeamais. The lethal concentrations (LC50 and LC90) of the PgEO showed it to be toxic against adult S. zeamais at 32.2 and 53.7 mg/mL, respectively. This is the first report on the chemical composition and in vitro biological activities of essential oil of P. glabra growing in Nigeria.

  5. Can vaccinia virus be replaced by MVA virus for testing virucidal activity of chemical disinfectants?

    Directory of Open Access Journals (Sweden)

    Rapp Ingrid

    2010-06-01

    Full Text Available Abstract Background Vaccinia virus strain Lister Elstree (VACV is a test virus in the DVV/RKI guidelines as representative of the stable enveloped viruses. Since the potential risk of laboratory-acquired infections with VACV persists and since the adverse effects of vaccination with VACV are described, the replacement of VACV by the modified vaccinia Ankara strain (MVA was studied by testing the activity of different chemical biocides in three German laboratories. Methods The inactivating properties of different chemical biocides (peracetic acid, aldehydes and alcohols were tested in a quantitative suspension test according to the DVV/RKI guideline. All tests were performed with a protein load of 10% fetal calf serum with both viruses in parallel using different concentrations and contact times. Residual virus was determined by endpoint dilution method. Results The chemical biocides exhibited similar virucidal activity against VACV and MVA. In three cases intra-laboratory differences were determined between VACV and MVA - 40% (v/v ethanol and 30% (v/v isopropanol are more active against MVA, whereas MVA seems more stable than VACV when testing with 0.05% glutardialdehyde. Test accuracy across the three participating laboratories was high. Remarkably inter-laboratory differences in the reduction factor were only observed in two cases. Conclusions Our data provide valuable information for the replacement of VACV by MVA for testing chemical biocides and disinfectants. Because MVA does not replicate in humans this would eliminate the potential risk of inadvertent inoculation with vaccinia virus and disease in non-vaccinated laboratory workers.

  6. Chemical acceleration of a neutral granulated blast-furnace slag activated by sodium carbonate

    International Nuclear Information System (INIS)

    Kovtun, Maxim; Kearsley, Elsabe P.; Shekhovtsova, Julia

    2015-01-01

    This paper presents results of a study on chemical acceleration of a neutral granulated blast-furnace slag activated using sodium carbonate. As strength development of alkali-activated slag cements containing neutral GBFS and sodium carbonate as activator at room temperature is known to be slow, three accelerators were investigated: sodium hydroxide, ordinary Portland cement and a combination of silica fume and slaked lime. In all cements, the main hydration product is C–(A)–S–H, but its structure varies between tobermorite and riversideite depending on the accelerator used. Calcite and gaylussite are present in all systems and they were formed due to either cation exchange reaction between the slag and the activator, or carbonation. With accelerators, compressive strength up to 15 MPa can be achieved within 24 h in comparison to 2.5 MPa after 48 h for a mix without an accelerator

  7. Chemical Composition, Antimicrobial and Antioxidant Activities of Essential Oils from Organically Cultivated Fennel Cultivars

    Directory of Open Access Journals (Sweden)

    Mahmoud A. Saleh

    2011-02-01

    Full Text Available Essential oils of the fruits of three organically grown cultivars of Egyptian fennel (Foeniculum vulgare var. azoricum, Foeniculum vulgare var. dulce and Foeniculum vulgare var. vulgare were examined for their chemical constituents, antimicrobial and antioxidant activities. Gas chromatography/mass spectrometry analysis of the essential oils revealed the presence of 18 major monoterpenoids in all three cultivars but their percentage in each oil were greatly different. trans-Anethole, estragole, fenchone and limonene were highly abundant in all of the examined oils. Antioxidant activities of the essential oils were evaluated using the DPPH radical scavenging, lipid peroxidation and metal chelating assays. Essential oils from the azoricum and dulce cultivars were more effective antioxidants than that from the vulgare cultivar. Antimicrobial activities of each oil were measured against two species of fungi, two species of Gram negative and two species of Gram positive bacteria. All three cultivars showed similar antimicrobial activity.

  8. Chemical composition, antimicrobial and antioxidant activities of essential oils from organically cultivated fennel cultivars.

    Science.gov (United States)

    Shahat, Abdelaaty A; Ibrahim, Abeer Y; Hendawy, Saber F; Omer, Elsayed A; Hammouda, Faiza M; Abdel-Rahman, Fawzia H; Saleh, Mahmoud A

    2011-02-01

    Essential oils of the fruits of three organically grown cultivars of Egyptian fennel (Foeniculum vulgare var. azoricum, Foeniculum vulgare var. dulce and Foeniculum vulgare var. vulgare) were examined for their chemical constituents, antimicrobial and antioxidant activities. Gas chromatography/mass spectrometry analysis of the essential oils revealed the presence of 18 major monoterpenoids in all three cultivars but their percentage in each oil were greatly different. trans-Anethole, estragole, fenchone and limonene were highly abundant in all of the examined oils. Antioxidant activities of the essential oils were evaluated using the DPPH radical scavenging, lipid peroxidation and metal chelating assays. Essential oils from the azoricum and dulce cultivars were more effective antioxidants than that from the vulgare cultivar. Antimicrobial activities of each oil were measured against two species of fungi, two species of Gram negative and two species of Gram positive bacteria. All three cultivars showed similar antimicrobial activity.

  9. Chemical compatibility study of lithium titanate with Indian reduced activation ferritic martensitic steel

    International Nuclear Information System (INIS)

    Sonak, Sagar; Jain, Uttam; Haldar, Rumu; Kumar, Sanjay

    2015-01-01

    Highlights: • Chemical compatibility between Li_2TiO_3 and Indian RAFM steel has been studied at ITER operating temperature. • The lithium titanate chemically reacted with ferritic martensitic steel to form a brittle and non-adherent oxide layer. • The layer grew in a parabolic manner as a function of heating time. • Diffusion of oxygen (from Li_2TiO_3) appears to be controlling the oxide layer. - Abstract: Chemical compatibility between lithium titanate and Indian reduced activation ferritic-martensitic steel (In-RAFMS) was studied for the first time under ITER operating temperature. Lithium titanate required for the study was synthesized in-house. Coupons of In-RAFMS were packed inside lithium titanate powder and heated at 550 °C up to 900 h under inert argon atmosphere. The lithium titanate chemically reacted with ferritic martensitic steel to form a brittle and non-adherent oxide layer. The layer grew in a parabolic manner as a function of heating time. Microstructural and phase evolution of this oxide layer was studied using XRD, SEM and EPMA. Iron and chromium enriched zones were found within the oxide layer. Diffusion of oxygen (from Li_2TiO_3) appears to be controlling the oxide layer.

  10. Role of low density lipoprotein in the activation of plasma lysolecithin acyltransferase activity. Effect of chemical and enzymatic modifications of the lipoprotein on enzyme activity.

    Science.gov (United States)

    Subbaiah, P V; Chen, C H; Bagdade, J D; Albers, J J

    1985-01-01

    The effect of various chemical and enzymatic modifications of low density lipoprotein (LDL) on its ability to activate the isolated human plasma lysolecithin acyltransferase (LAT) was studied. Removal of all lipids from LDL resulted in the complete loss of LAT activation. Removal of only neutral lipids by extraction with heptane retained up to 50% of the original activity, which was not increased further by reconstitution of the LDL with the extracted lipids. Hydrolysis of the diacylphosphoglycerides of the LDL with phospholipases resulted in complete loss of LAT activation which was partially restored by the addition of egg lecithin. Hydrolysis of more than 4% of LDL protein by trypsin led to a linear decrease in activity with complete loss of activity occurring when about 25% of the LDL protein is hydrolyzed. Modification of the arginine groups of LDL reversibly inhibited the activation of LAT. Modification of lysine residues of LDL by acetylation, acetoacetylation or succinylation also abolished its ability to activate lysolecithin acylation.

  11. 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.

  12. Antimicrobial Activity and Chemical Composition of Three Essential Oils Extracted from Mediterranean Aromatic Plants.

    Science.gov (United States)

    Elshafie, Hazem S; Sakr, Shimaa; Mang, Stefania M; Belviso, Sandra; De Feo, Vincenzo; Camele, Ippolito

    2016-11-01

    There is a growing interest in essential oils (EOs) as possible alternatives for traditional chemical pesticides. This study was carried out to characterize the chemical composition of the three EOs extracted from Verbena officinalis, Majorana hortensis, and Salvia officinalis using gas chromatography (GC) and GC-mass spectrometry (GC-MS) and to evaluate in vitro their efficacy against some phyto or human pathogens. The antifungal activity was investigated against Colletotrichum acutatum and Botrytis cinerea in comparison with Azoxystrobin as a large spectrum fungicide. Antibacterial activity was evaluated against Bacillus megaterium, Bacillus mojavensis, and Clavibacter michiganensis (G+ve) and Escherichia coli, Xanthomonas campestris, Pseudomonas savastanoi, and P. syringae pv. phaseolicola (G-ve) compared to a synthetic antibiotic tetracycline. Minimum inhibitory concentration was evaluated against the above tested fungi using 96-well microplate method. Results showed that the chemical structure of the three studied EOs was mainly composed of monoterpene compounds and all oils belong to the chemotype carvacrol/thymol. Results of GC analysis identified 64 compounds, which were identified based on their mass to charge ratio. Furthermore, the different concentrations of studied EOs inhibited the growth of tested microorganism in a dose-dependent manner.

  13. Activities of the Institute of Chemical Processing of Coal at Zabrze

    Energy Technology Data Exchange (ETDEWEB)

    Dreszer, K.

    1995-12-31

    The Institute of Chemical Processing of Coal at Zabrze was established in 1955. The works on carbochemical technologies have been, therefore, carried out at the Institute for 40 years. The targets of the Institute`s activities are research, scientific and developing works regarding a sensible utilization of fuels via their processing into more refined forms, safe environment, highly efficient use of energy carriers and technological products of special quality. The Institute of Chemical Processing of Coal has been dealing with the following: optimized use of home hard coals; improvement of classic coal coking technologies, processing and utilization of volatile coking products; production technologies of low emission rate fuels for communal management; analyses of coal processing technologies; new technologies aimed at increasing the efficiency of coal utilization for energy-generating purposes, especially in industry and studies on the ecological aspects of these processes; production technologies of sorbents and carbon activating agents and technologies of the utilization; rationalization of water and wastes management in the metallurgical and chemical industries in connection with removal of pollution especially dangerous to the environment from wastes; utilization technologies of refined materials (electrode cokes, binders, impregnating agents) for making electrodes, refractories and new generation construction carbon materials; production technologies of high quality bituminous and bituminous and resin coating, anti-corrosive and insulation materials; environmentally friendly utilization technologies for power station, mine and other wastes, and dedusting processes in industrial gas streams.

  14. Evaluation of activities of carbons in chemical equilibrium with uranium carbonitride

    International Nuclear Information System (INIS)

    Katsura, Masahiro; Hirota, Masayuki; Miyake, Masanobu; Hamada, Kazuo.

    1992-01-01

    A mixture of uranium sesquinitride and carbon was prepared by the reaction of UC of UC 2 with N 2 in the temperature range from 700 to 1400degC. When the mixture of uranium sesquinitride and carbon is kept at temperatures above 1200degC in the atmosphere of N 2 at low pressure, the state where uranium carbonitride (UC 1-x N x ) and carbon are present together in chemical equilibrium will be established. A thermodynamic analysis suggests that, in the equilibrium state, the composition of UC 1-x N x is determined by the chemical activity of carbon, a c , which is related to the chemical potential of the carbon, μ c , by the equation, μ c = μ c deg + RT 1n a c . Here μ c deg refers to graphite, which is usually taken as the standard state of carbon (a c = 1). Mixtures of U 2 N 3 and carbon with several degrees of graphitization were heat-treated at 1400degC, and the composition of UC 1-x N x in the reaction product was determined. From these experimental results and the thermodynamic analysis, values of the activity of the carbon coexisting with UC 1-x N x were estimated. (author)

  15. Metal compounds in zeolites as active components of chemisorption and catalysis. Quantum chemical approach

    International Nuclear Information System (INIS)

    Zhidomirov, G.M.

    1996-01-01

    A short review of possible catalitic active sites associated with various types of metal species in zoolite is presented. The structural and electronic peculiarity of aluminum ions in zeolite lattice and their distribution in the lattice are discussed on the basis of quantum chemical calculations in connection with the formation of Broensted activity of zeolites. Various molecular models of Lewis Acid Sites associated the extra-lattice oxide-hydroxide aluminum species have been investigated by means of density functional model cluster calculations using CO molecule as a probe. Probable ways of formation of the selective oxidation center in FeZSM-5 by decomposition of dinitrogen monoxide have been studied by ab-initio quantum chemical calculations. The immediate oxidizing site is reasonably represented by the binuclear iron-hydroxide cluster with peroxo-like fragment located between iron atoms. Various probable intermediates of the selective oxidation center formation resulted from interaction of a hydroperoxide molecule with a lattice titanium ion in titanium silicalite have been investigated by quantum chemical calculations. It was concluded that this reaction requires essential structural reconstruction in the vicinity of the titanium ion. Probability of this structural reconstruction is discussed. Possible reasons of an electron-deficient and electron-enriched state of metal particles entrapped in zoolite cavities are discussed. Also, various probable molecular models of such modified metal particles in zeolite are considered

  16. MORPHO-CHEMICAL DESCRIPTION AND ANTIMICROBIAL ACTIVITY OF DIFFERENT OCIMUM SPECIES

    Directory of Open Access Journals (Sweden)

    KAKARAPARTHI PANDU SASTRY

    2012-12-01

    Full Text Available Basil is a popular medicinal and culinary herb, and its essential oils have been used extensively for many years in food products, perfumery, dental and oral products. Basil essential oils and their principal constituents were found to exhibit antimicrobial activity against a wide range of Gram-negative and Gram-positive bacteria, yeast, and mould. The essential oils obtained from aerial parts of three different species of Ocimum comprising twenty one germplasm lines were investigated for their essential oil composition and antimicrobial activity during 2010. Essential oils from seventeen germplasm lines in Ocimum basilicum and two each in Ocimum tenuiflorum and Ocimum gratissimum were investigated for anti-microbial activity against four bacterial strains (Staphylococcus aureus, Bacillus sps., Escherichia coli and Pseudomonas aeruginosa. The morpho-chemotypes exhibited wide variability for morphological and chemical traits. Anti-bacterial activity was found to be high for Staphylococcus aureus, moderate for Escherichia coli, low for Bacillus and Pseudomonas aeruginosa was highly resistant. The essential oils of Pale Green-Broad Leaves (O. basilicum and CIM Ayu (O. gratissimum exhibited significant antibacterial activity against both S. aureus and E. coli signifying them promising for anti-bacterial activity. No relationship was observed between chemotype specificity and anti-bacterial activity, indicating that apart from major components of essential oil, minor components and other factors may be responsible for anti-microbial activities.

  17. The Chemical Characterization of Nigerian Propolis samples and Their Activity Against Trypanosoma brucei.

    Science.gov (United States)

    Omar, Ruwida; Igoli, John O; Zhang, Tong; Gray, Alexander I; Ebiloma, Godwin U; Clements, Carol J; Fearnley, James; Edrada Ebel, RuAngeli; Paget, Tim; de Koning, Harry P; Watson, David G

    2017-04-19

    Profiling of extracts from twelve propolis samples collected from eight regions in Nigeria was carried out using high performance liquid chromatography (LC) coupled with evaporative light scattering (ELSD), ultraviolet detection (UV) and mass spectrometry (MS), gas chromatography mass spectrometry (GC-MS) and nuclear magnetic resonance spectroscopy (NMR). Principal component analysis (PCA) of the processed LC-MS data demonstrated the varying chemical composition of the samples. Most of the samples were active against Trypanosoma b. brucei with the highest activity being in the samples from Southern Nigeria. The more active samples were fractionated in order to isolate the component(s) responsible for their activity using medium pressure liquid chromatography (MPLC). Three xanthones, 1,3,7-trihydroxy-2,8-di-(3-methylbut-2-enyl)xanthone, 1,3,7-trihydroxy-4,8-di-(3-methylbut-2-enyl)xanthone a previously undescribed xanthone and three triterpenes: ambonic acid, mangiferonic acid and a mixture of α-amyrin with mangiferonic acid (1:3) were isolated and characterised by NMR and LC-MS. These compounds all displayed strong inhibitory activity against T.b. brucei but none of them had higher activity than the crude extracts. Partial least squares (PLS) modelling of the anti-trypanosomal activity of the sample extracts using the LC-MS data indicated that high activity in the extracts, as judged from LCMS 2 data, could be correlated to denticulatain isomers in the extracts.

  18. [Chemical Constituents from Leaves of Hibiscus syriacus and Their α-Glucosidase Inhibitory Activities].

    Science.gov (United States)

    Wei, Qiang; Ji, Xiao-ying; Xu, Fei; Li, Qian-rong; Yin, Hao

    2015-05-01

    To study the chemical constituents from Hibiscus syriacus leaves and their α-glucosidase inhibitory activities. Column chromatography including macroporous resins, silica gel and Sephadex LH-20 were used for the isolation and purification of all compounds. Spectroscopic methods including physical and chemical properties, 1H-NMR and 13C-NMR were used for the identification of structures. Their α-glucosidase inhibitory activities were detected by a 96-well microplate. 15 compounds were isolated and identified as β-sitosterol(1), β-daucostero (2), β-amyrin (3), oleanolic acid (4), stigmast-4-en-3-one (5), friedelin (6), syriacusin A (7), kaempferol (8), isovitexin (9), vitexin (10), apigenin (11), apigenin-7-O-β-D-glucopyranoside (12), luteolin-7-O-β-D-glucopyranoside (13), vitexin-7-O-β-D-glucopyranoside (14) and rutin (15). All the compounds are isolated from the leaves of Hibiscus syriacus for the first time. Taking acarbose as positive control, the α-glucosidase inhibitory activities of 15 compounds were evaluated. Compounds 7 and 9 have shown strong α-glucosidase inhibitory activities with IC50 of 39.03 ± 0.38 and 32.12 ± 0.62 mg/L, inhibition ratio of 94.95% and 97.15%, respectively.

  19. Determination of chemical composition, total phenolic content and antioxidant activity of xylanthemum macropodum

    International Nuclear Information System (INIS)

    Samiullah, A.; Tareen, R.B.; Khan, N.; Akber, A.; Ali, I.; Khan, A.K.

    2017-01-01

    Evaluation of the phytochemistry, total phenolic content and antioxidant activity of the endemic plant of northern Balochistan Xylanthemum Macropodum of the Asteraceae family, is reported for the first time in this document. Chemical composition of Xylanthemum Macropodum was determined using well-established chemical tests and modern spectroscopic techniques. Extracts were taken from the whole plant using methanol and the extracts were tested for phytochemicals (secondary metabolites), total phenolic content (TPC) and antioxidant activity. The phytochemical (biochemical) examination of Xylanthemum Macropodum exposed the presence of alkaloids, phenols, steroids, flavonoids, tannins, terpenoids, saponins, coumarins, carbohydrates, cardiac glycosides, reducing sugars, and quinines. TPC of crude methanolic extract (CME) of plant was determined using Folin-Ciocalteu's reagent. The TPC determined was 256mg of tannic acid Eq/g of extract. Antioxidant activities were determined spectrophotometrically using the DPPH assay and Ferric ion (Fe/sup +3/) reducing antioxidant power assay. The potency of the DPPH assay of Xylanthemum Macropodum extract was 68% for the 0.10 mg/ml concentration and the FRAP value of the extract was 3.368 mmol Fe/sup +2//g of extract. Xylanthemum Macropodum has proved to be very rich in secondary metabolites, natural phenolics and has a very potent antioxidant activity. (author)

  20. Chemical Composition and Biological Activities of Allium roseum L. var. grandiflorum Briq. Essential Oil.

    Science.gov (United States)

    Touihri, Imen; Boukhris, Maher; Marrakchi, Naziha; Luis, José; Hanchi, Belgacem; Kallech-Ziri, Olfa

    2015-01-01

    Allium roseum L. (Alliaceae) endemic mediterranean specie was represented in the North Africa by 12 different taxa. In the present study, chemical composition, antiproliferative, antioxidant and antimicrobial activities of the essential oil extracted from A. roseum var. grandiflorum Briq. bulbs collected in the North of Tunisia were investigated. Chemical characterization has shown methyl methanethiosulfinate as major sulphurous compounds. A. roseum bulbs essential oil provides interesting antiproliferative activity against two human colonic adenocarcinoma HT29 and CACO2 cell lines in dose-dependent manner with a half-maximal inhibition (IC50) of 4.64 µg/mL and 8.22 µg/mL respectively. The antioxidant activity, as determined by FRAP assay, was 285 µmol equivalent Trolox/g of essential oil. The scavenging effect on DPPH radicals of essential oil was estimated as IC50 values at 156 µg/mL. The inhibition of superoxide anion production in a model of cancer cell lines was significant for both lines HT29 and CACO2 with IC50 of 20.25 µg/mL and 29.12 µg/mL respectively. Allium roseum essential oil exhibited antibacterial and antifungal activities with a high effectiveness against Candida albicans given by an MIC value of 0.019 mg/mL. This biological effect appears to be related mainly to the presence of organosulfur compounds.

  1. Chemical Characterization and Antioxidant, Antimicrobial, and Anti-Inflammatory Activities of South Brazilian Organic Propolis

    Science.gov (United States)

    Tiveron, Ana Paula; Rosalen, Pedro Luiz; Franchin, Marcelo; Lacerda, Risia Cristina Coelho; Bueno-Silva, Bruno; Benso, Bruna; Denny, Carina; Ikegaki, Masaharu; de Alencar, Severino Matias

    2016-01-01

    South Brazilian organic propolis (OP), which has never been studied before, was assessed and its chemical composition, scavenging potential of reactive oxygen species, antimicrobial and anti-inflammatory activities are herein presented. Based on the chemical profile obtained using HPLC, OP was grouped into seven variants (OP1–OP7) and all of them exhibited high scavenging activity, mainly against superoxide and hypochlorous acid species. OP1, OP2, and OP3 had the smallest minimal inhibitory concentration (MIC) against Gram-positive bacteria Streptococcus mutans, Streptococcus oralis, and Streptococcus aureus (12.5–100 μg/mL). OP1, OP2, OP3, and OP4 were more effective against Pseudomonas aeruginosa (Gram-negative), with MIC values ranging from 100 to 200 μg/mL. OP6 showed anti-inflammatory activity by decreasing NF-kB activation and TNF-α release in RAW 264.7 macrophages, and expressing the NF-κB-luciferase reporter stable gene. Therefore, south Brazilian OP can be considered an excellent source of bioactive compounds with great potential of application in the pharmaceutical and food industry. PMID:27802316

  2. Application of chemical methods to assess the mechanism of alkali activation in low calcium fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Arjunan, P.; Silsbee, M.R.; Roy, D.M. [Pennsylvania State Univ., PA (United States). Materials Research Lab.

    1999-11-01

    A better understanding of the amount of fly ash unreacted remaining after alkali activation of low calcium fly ash is necessary for elucidating the underlying alkali activation mechanism. An approach to this determination is reported in this study which utilizes an ethylenediamine tetraacetic acid/triethanolamine/NaOH mixture to determine the unreacted fly ash particles present in an OPC-low calcium fly ash mixture, with and without alkali activation. This study also uses another chemical technique called orthophosphoric acid dissolution method to assess the amount of unreacted crystalline phases present in hydrated OPC-ash mixtures at different ages of hydration. The information obtained from these two chemical techniques was used to identify the nature of unreacted fly ash particles present in the hydrated samples. The amount of unreacted fly ash and the compressive strength data were correlated to assess the extent of influence of alkali activation on the reactivity of the amorphous and crystalline phase content of the low calcium fly ash.

  3. Comparative Study of Chemical Composition and Biological Activity of Yellow, Green, Brown, and Red Brazilian Propolis

    Directory of Open Access Journals (Sweden)

    Christiane Schineider Machado

    2016-01-01

    Full Text Available The chemical composition and biological activity of a sample of yellow propolis from Mato Grosso do Sul, Brazil (EEP-Y MS, were investigated for the first time and compared with green, brown, and red types of Brazilian propolis and with a sample of yellow propolis from Cuba. Overall, EEP-Y MS had different qualitative chemical profiles, as well as different cytotoxic and antimicrobial activities when compared to the other types of propolis assessed in this study and it is a different chemotype of Brazilian propolis. Absence of phenolic compounds and the presence of mixtures of aliphatic compounds in yellow propolis were determined by analysing 1H-NMR spectra and fifteen terpenes were identified by GC-MS. EEP-Y MS showed cytotoxic activity against human tumour strain OVCAR-8 but was not active against Gram-negative or Gram-positive bacteria. Our results confirm the difficulty of establishing a uniform quality standard for propolis from diverse geographical origins. The most appropriate pharmacological applications of yellow types of propolis must be further investigated.

  4. Chemical constituents and evaluation of antibacterial activity of Macroptilium lathyroides (L.) Urb. (Fabaceae)

    International Nuclear Information System (INIS)

    Sousa, Leoncio M. de; Gois, Roberto W. da S.; Lemos, Telma L. G.; Arriaga, Angela M. C.; Andrade-Neto, Manoel; Santiago, Gilvandete M.P.; Braz-Filho, Raimundo; Costa, Jose G.M. da; Rodrigues, Fabiola F.G.

    2013-01-01

    The chemical investigation of the stems and branches of Macroptilium lathyroides led to the isolation of a mixture of β-sitosterol and stigmasterol. The extracts from the roots allowed the isolation of lasiodiplodin, a mixture of stigmast-4-en-6β-ol-3-one and stigmast-4,22-dien-6β-ol-3-one, de-O-methyllasiodiplodin, genistein and lupinalbin A. The structures of the isolated compounds were assigned on the basis of their NMR data, including comparison of their spectral data with values described in the literature. The antibacterial activity of crude extracts from stems, branches and roots was evaluated. This is the first report involving the chemical investigation of this species. (author)

  5. Suppression of SOS-inducing activity of chemical mutagens by metabolites from microbial transformation of (-)-isolongifolene.

    Science.gov (United States)

    Sakata, Kazuki; Oda, Yoshimitsu; Miyazawa, Mitsuo

    2010-02-24

    In this study, biotransformation of (-)-isolongifolene (1) by Glomerella cingulata and suppressive effect on umuC gene expression by chemical mutagens 2-(2-furyl)-3-(5-nitro-2-furyl)acrylamide (furylfuramide) and aflatoxin B(1) (AFB(1)) of the SOS response in Salmonella typhimurium TA1535/pSK1002 were investigated. Initially, 1 was carried out the microbial transformation by G. cingulata. The result found that 1 was converted into (-)-isolongifolen-9-one (2), (-)-(2S)-13-hydroxy-isolongifolen-9-one (3), and (-)-(4R)-4-hydroxy-isolongifolen-9-one (4) by G. cingulata, and their conversion rates were 60, 25, and 15%, respectively. The metabolites suppressed the SOS-inducing activity of furylfuramid and AFB(1) in the umu test. Comound 2 showed gene expression by chemical mutagens furylfuramide and AFB(1) was suppressed 54 and 50% at <0.5 mM, respectively. Compound 2 is the most effective compound in this experiment.

  6. Chemical contents in Lygeum spartum L. using instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    Nedjimi, Bouzid

    2015-01-01

    The present investigation was conducted to determine the chemical contents of Lygeum spartum L. (Poaceae). Samples were analyzed in order to determine essential (Ca, K, Na, Fe, Co) and some potentially toxic elements (Eu, Sb, Tb) using instrumental neutron activation analysis (INAA). In general chemical element contents were in substantial amounts to meet adult sheep requirements. Potential intake of Ca, K, Zn, Co and Fe by ruminant weighing 50 kg BW consuming 2.0 kg per day DM was sufficient to satisfy their requirements. However, only Na level was still insufficient to meet the requirements for grazing ruminants. Potential toxic elements in this species were within the safety baseline of all the assayed elements recommended by NRC. Na supplementation would seem to be necessary in this zone, for optimum productivity of grazing animals.

  7. Activation of aluminum as an effective reducing agent by pitting corrosion for wet-chemical synthesis.

    Science.gov (United States)

    Li, Wei; Cochell, Thomas; Manthiram, Arumugam

    2013-01-01

    Metallic aluminum (Al) is of interest as a reducing agent because of its low standard reduction potential. However, its surface is invariably covered with a dense aluminum oxide film, which prevents its effective use as a reducing agent in wet-chemical synthesis. Pitting corrosion, known as an undesired reaction destroying Al and is enhanced by anions such as F⁻, Cl⁻, and Br⁻ in aqueous solutions, is applied here for the first time to activate Al as a reducing agent for wet-chemical synthesis of a diverse array of metals and alloys. Specifically, we demonstrate the synthesis of highly dispersed palladium nanoparticles on carbon black with stabilizers and the intermetallic Cu₂Sb/C, which are promising candidates, respectively, for fuel cell catalysts and lithium-ion battery anodes. Atomic hydrogen, an intermediate during the pitting corrosion of Al in protonic solvents (e.g., water and ethylene glycol), is validated as the actual reducing agent.

  8. Relations between chemical species distribution and the fluctuating activity of Vulcano (Italy)

    Energy Technology Data Exchange (ETDEWEB)

    Martini, M.; Legittimo, P.C.

    1984-09-01

    Five years of systematic observation of the fumaroles of Vulcano have permitted the detection of some compositional trends coincident with a fluctuation in temperature. A gradual decrease of CO/sub 2/, H/sub 2/S+SO/sup 2/, HF was observed with the lowering of temperature, while HCl slightly increased. These physical-chemical characteristics of the system are not readily explained as simply produced by different stages in magma degassing, and the previous hypothesis of the insignificant influence of a brackish aquifer on the fumaroles still appears a reliable working model. R-mode factor analysis allowed the differentiated role of chemical species to be distinguished for which different genetic processes can be derived. The ratios HF/HCl and SO/sub 2//H/sub 2/S are taken as indicators of the changing activity of the system, and also the available data for Usu (Japan) and Mount St. Helens (USA) are considered.

  9. Chemical composition and biological activities of extracts and essential oil of Boswellia dalzielii leaves.

    Science.gov (United States)

    Kohoude, Midéko Justin; Gbaguidi, Fernand; Agbani, Pierre; Ayedoun, Marc-Abel; Cazaux, Sylvie; Bouajila, Jalloul

    2017-12-01

    Boswellia dalzielii Hutch. (Burseraceae) is an aromatic plant. The leaves are used for beverage flavouring. This study investigates the chemical composition and biological activities of various extracts. The essential oil was prepared via hydrodistillation. Identification and quantification were realized via GC-MS and GC-FID. Consecutive extractions (cyclohexane, dichloromethane, ethyl acetate and methanol) were carried out and various chemical groups (phenolics, flavonoids, tannins, antocyanins and sugar) were quantified. The volatile compounds of organic extracts were identified before and after derivatization. Antioxidant, antihyperuricemia, anti-Alzheimer, anti-inflammatory and anticancer activities were evaluated. In the essential oil, 50 compounds were identified, including 3-carene (27.72%) and α-pinene (15.18%). 2,5-Dihydroxy acetophenone and β-d-xylopyranose were identified in the methanol extract. Higher phenolic (315.97 g GAE/kg dry mass) and flavonoid (37.19 g QE/kg dry mass) contents were observed in the methanol extract. The methanol extract has presented remarkable IC 50  =   6.10 mg/L for antiDPPH, 35.10 mg/L for antixanthine oxidase and 28.01 mg/L for anti-5-lipoxygenase. For acetylcholinesterase inhibition, the best IC 50 (76.20 and 67.10 mg/L) were observed, respectively, with an ethyl acetate extract and the essential oil. At 50 mg/L, the dichloromethane extract inhibited OVCAR-3 cell lines by 65.10%, while cyclohexane extract inhibited IGROV-1 cell lines by 92.60%. Biological activities were fully correlated with the chemical groups of the extracts. The ethyl acetate and methanol extracts could be considered as potential alternatives for use in dietary supplements for the prevention or treatment of diseases because of these extracts natural antioxidant, antihyperuricemic and anti-inflammatory activities.

  10. Treatment of Active Acne Vulgaris by Chemical Peeling Using 88% Lactic Acid

    Directory of Open Access Journals (Sweden)

    Khalifa E. Sharquie

    2014-10-01

    Full Text Available Introduction: The etiopathogenesis of acne vulgaris is multifactorial, and its therapy is prolonged course that might be not accepted by many patients. Most recently TCA 35% one session peeling gave complete clearance and full remission for active acne vulgaris. Lactic acid has been used effectively as therapeutic topical agents for many skin diseases. Aim: To evaluate the efficacy and safety of chemical peeling using 88% lactic acid solution in the treatment of active acne vulgaris. Material and Methods: This clinical, interventional, therapeutic study was done at the Department of Dermatology, Baghdad Teaching Hospital, during the period from October 2012 to October 2013. Twenty five patients with active acne vulgaris were included, 15 (60% females and 10 (40% males and their ages ranged from 16-36 (21.5000± 5.46279 years. Fifteen patients were associated with acne scars. Three chemical peels using 88% lactic acid solution was carried out two weeks apart for patients with active acne vulgaris with or without scarring. Scoring for active acne vulgaris and acne scar was done for each case before and after operation to evaluate the severity of acne and the degree of scar before and after treatment. All patients were with Fitzpatrick’s skin types III and IV. Patients were followed up every two weeks during period of therapy and monthly for 3 months after stopping the treatment. Results: Twenty five patients with active acne vulgaris were treated with 3 sessions of lactic acid, fifteen patients had associated acne scar. Scoring for active acne vulgaris including papules and pustules showed highly statistically significant reduction after 2 weeks of therapy (p=0.0001, after 4 weeks (p=0.0001and after 6 weeks (p=0.0001, with percent reduction 87.2% for papules and 94% for pustules after end of sessions while after 3 months follow up the reduction rate for papules 93.8% and p-value (p=0.001 and for pustules 97.6% and (p=0.0001. While the scarring

  11. Helichrysum gymnocephalum Essential Oil: Chemical Composition and Cytotoxic, Antimalarial and Antioxidant Activities, Attribution of the Activity Origin by Correlations

    Directory of Open Access Journals (Sweden)

    François Couderc

    2011-09-01

    Full Text Available Helichrysum gymnocephalum essential oil (EO was prepared by hydrodistillation of its leaves and characterized by GC-MS and quantified by GC-FID. Twenty three compounds were identified. 1,8-Cineole (47.4%, bicyclosesquiphellandrene (5.6%, γ-curcumene (5.6%, α-amorphene (5.1% and bicyclogermacrene (5% were the main components. Our results confirmed the important chemical variability of H. gymnocephalum. The essential oil was tested in vitro for cytotoxic (on human breast cancer cells MCF-7, antimalarial (Plasmodium falciparum: FcB1-Columbia strain, chloroquine-resistant and antioxidant (ABTS and DPPH assays activities. H. gymnocephalum EO was found to be active against MCF-7 cells, with an IC50 of 16 ± 2 mg/L. The essential oil was active against P. falciparum (IC50 = 25 ± 1 mg/L. However, the essential oil exhibited a poor antioxidant activity in the DPPH (IC50 value > 1,000 mg/L and ABTS (IC50 value = 1,487.67 ± 47.70 mg/L assays. We have reviewed the existing results on the anticancer activity of essential oils on MCF-7 cell line and on their antiplasmodial activity against the P. falciparum. The aim was to establish correlations between the identified compounds and their biological activities (antiplasmodial and anticancer. β-Selinene (R² = 0.76, α-terpinolene (R² = 0.88 and aromadendrene (R² = 0.90 presented a higher relationship with the anti-cancer activity. However, only calamenene (R² = 0.70 showed a significant correlation for the antiplasmodial activity.

  12. Helichrysum gymnocephalum essential oil: chemical composition and cytotoxic, antimalarial and antioxidant activities, attribution of the activity origin by correlations.

    Science.gov (United States)

    Afoulous, Samia; Ferhout, Hicham; Raoelison, Emmanuel Guy; Valentin, Alexis; Moukarzel, Béatrice; Couderc, François; Bouajila, Jalloul

    2011-09-29

    Helichrysum gymnocephalum essential oil (EO) was prepared by hydrodistillation of its leaves and characterized by GC-MS and quantified by GC-FID. Twenty three compounds were identified. 1,8-Cineole (47.4%), bicyclosesquiphellandrene (5.6%), γ-curcumene (5.6%), α-amorphene (5.1%) and bicyclogermacrene (5%) were the main components. Our results confirmed the important chemical variability of H. gymnocephalum. The essential oil was tested in vitro for cytotoxic (on human breast cancer cells MCF-7), antimalarial (Plasmodium falciparum: FcB1-Columbia strain, chloroquine-resistant) and antioxidant (ABTS and DPPH assays) activities. H. gymnocephalum EO was found to be active against MCF-7 cells, with an IC(50) of 16 ± 2 mg/L. The essential oil was active against P. falciparum (IC(50) = 25 ± 1 mg/L). However, the essential oil exhibited a poor antioxidant activity in the DPPH (IC(50) value > 1,000 mg/L) and ABTS (IC(50) value = 1,487.67 ± 47.70 mg/L) assays. We have reviewed the existing results on the anticancer activity of essential oils on MCF-7 cell line and on their antiplasmodial activity against the P. falciparum. The aim was to establish correlations between the identified compounds and their biological activities (antiplasmodial and anticancer). β-Selinene (R² = 0.76), α-terpinolene (R² = 0.88) and aromadendrene (R² = 0.90) presented a higher relationship with the anti-cancer activity. However, only calamenene (R² = 0.70) showed a significant correlation for the antiplasmodial activity.

  13. Predicting allergic contact dermatitis: a hierarchical structure activity relationship (SAR) approach to chemical classification using topological and quantum chemical descriptors

    Science.gov (United States)

    Basak, Subhash C.; Mills, Denise; Hawkins, Douglas M.

    2008-06-01

    A hierarchical classification study was carried out based on a set of 70 chemicals—35 which produce allergic contact dermatitis (ACD) and 35 which do not. This approach was implemented using a regular ridge regression computer code, followed by conversion of regression output to binary data values. The hierarchical descriptor classes used in the modeling include topostructural (TS), topochemical (TC), and quantum chemical (QC), all of which are based solely on chemical structure. The concordance, sensitivity, and specificity are reported. The model based on the TC descriptors was found to be the best, while the TS model was extremely poor.

  14. Chemical Composition and Antioxidant Activity of Essential Oil and Organic Extracts of Premna integrifolia Linn

    Directory of Open Access Journals (Sweden)

    Sharif M. Al-Reza

    Full Text Available ABSTRACT This study was designed to examine the chemical composition and in vitro antioxidant activity of the hydrodistillated essential oil and various extracts obtained from Premna integrifolia Linn. GC-MS analysis of the essential oil was resulted in determination 29 different compounds, representing 95.73% of total oil. Antioxidant activities of the essential oil and organic extracts of chloroform, ethyl acetate and methanol were determined by three different test systems namely DPPH (2,2-diphenyl-1-picrylhydrazyl, superoxide and nitric oxide radical scavenging assays. The essential oil and methanol extract showed potent antioxidant activity among all the tested samples. Furthermore, the amount of total phenolic compounds was determined and its content in methanol extract was the highest as compared to other samples. The results indicate that the essential oil and extracts of Premna integrifolia could serve as an important bio-resource of antioxidants for using in the pharmaceutical industries.

  15. "Chemical composition and antimicrobial activity of the essential oil of Ferulago Bernardii Tomk. and M. Pimen"

    Directory of Open Access Journals (Sweden)

    "Farahnaz Khalighi-Sigaroodi

    2005-05-01

    Full Text Available The chemical composition of the essential oil of the aerial parts of Ferulago Bernardii from Iran was analysed by GC and GC/MS. Sixty constituents were found representing 87.9% of the oil. The main constituents of the essential oil were 2,4,5-trimethyl-benzaldehyde (21.2%, α-pinene (17.0%,spathulenol (5.0%, cis-chrysanthenyl acetate (4.4% and caryophyllene oxide (3.2%. Antimicrobial activity of the essential oil of Ferulago Bernardii by the broth dilution method in comparison with Gentamycin and Fluconazole as standard showed weak activity against Staphylococcus aureus, Bacilus subtilis, Escherichia coli, Candida albicans and Aspergillus niger. The essential oil did not show any activity against Pseudomonas aeruginosa.

  16. Neutron activation of selenium and arsenic with or without chemical separation

    International Nuclear Information System (INIS)

    Woittiez, J.R.W.

    1988-01-01

    At the Netherland Energy Research Foundation, neutron activation analysis (NAA) is one of the available techniques for elemental analysis. As the technique is potentially very powerful, considerable effort has been invested during the last 2 yr to optimize the multielement performance and to focus simultaneously on the best achievable single-element determination. This last activity implies concentrating the attention on measuring a well-defined signal rather than on software to evaluate complicated signals. As several irradiation facilities can be used, it is possible to choose the best obtainable instrumental activation technique. For the analysis of trace elements on the nanogram per gram level in biological material, however, the reintroduction of chemical separation of irradiated samples is inevitable. This paper presents recent results on applications of this approach. Although several well-documented techniques have been adapted, installed, and applied, and results are obtained for cadmium, molybdenum, chromium, cobalt, tin, iron, and mercury, this discussion is limited to selenium and arsenic

  17. Chemical composition and biological activities of the essential oils from two Pereskia species grown in Brazil.

    Science.gov (United States)

    Souza, Lucéia Fatima; De Barros, Ingrid Bergman Inchausti; Mancini, Emilia; De Martino, Laura; Scandolera, Elia; De Feo, Vincenzo

    2014-12-01

    The chemical composition of the essential oils of Pereskia aculeata Mill. and P. grandifolia Haw. (Cactaceae), grown in Brazil, was studied by means of GC and GC-MS. In all, 37 compounds were identified, 30 for P. aculeata and 15 for P. grandifolia. Oxygenated diterpenes are the main constituents, both in the oil ofP. grandifolia (55.5%) and in that ofP. aculeata (29.4%). The essential oils were evaluated for their in vitro phytotoxic activity against germination and initial radicle growth of Raphanus sativus L., Sinapis arvensis L., and Phalaris canariensis L. seeds. The essential oil of P. grandifolia, at all doses tested, significantly inhibited the radicle elongation of R. sativus. Moreover, the antimicrobial activity of the essential oils was assayed against ten bacterial strains. The essential oils showed weak inhibitory activity against the Gram-positive pathogens.

  18. Chemical composition and biological activities of the essential oil from Anredera cordifolia grown in Brazil.

    Science.gov (United States)

    Souza, Lucéia Fátima; de Barros, Ingrid Bergman Inchausti; Mancini, Emilia; De Martino, Laura; Scandolera, Elia; De Feo, Vincenzo

    2014-07-01

    The chemical composition of the essential oil of Anredera cordifolia (Ten.) Steenis (Basellaceae), grown in Brazil, was studied by means of GC and GC-MS analysis. In all, 19 compounds were identified, accounting for 91.6% of the total oil; hydrocarbons were the main constituents (67.7%). The essential oil was evaluated for its in vitro potential phytotoxic activity against germination and initial radicle growth of Raphanus sativus L., Sinapis arvensis L., and Phalaris canariensis L. seeds. At 1.25 microg/mL and 0.625 microg/mL, the oil significantly promoted the germination of S. arvensis. Moreover, the antimicrobial activity of the essential oil was assayed against ten bacterial strains. The essential oil showed a weak inhibitory activity against the Gram-positive pathogens.

  19. Chemical composition and antifungal activity of the essential oils of Schinus weinmannifolius collected in the spring and winter.

    Science.gov (United States)

    Hernandes, Camila; Taleb-Contini, Silvia H; Bartolomeu, Ana Carolina D; Bertoni, Bianca W; França, Suzelei C; Pereira, Ana Maria S

    2014-09-01

    Reports on the chemical and pharmacological profile of the essential oil of Schinus weinmannifolius do not exist, although other Schinus species have been widely investigated for their biological activities. This work aimed to evaluate the chemical composition and antimicrobial activity of the essential oil of S. weinmannifolius collected in the spring and winter. The essential oils were extracted by hydrodistillation, analyzed by GC/MS and submitted to microdilution tests, to determine the minimum inhibitory concentration. The oils displayed different chemical composition and antimicrobial action. Bicyclogermacrene and limonene predominated in the oils extracted in the winter and spring, respectively, whereas only the latter oil exhibited antifungal activity.

  20. Chemical compounds and antimicrobial activity of petitgrain (Citrus aurantium L. var. amara essential oil

    Directory of Open Access Journals (Sweden)

    Gniewosz Małgorzata

    2017-12-01

    Full Text Available Introduction: Due to its low cost and easy availability on the market, the petitgrain oil is commonly used in food, cosmetics, and aromatherapy. Objective: The examination of chemical composition and antibacterial activity of commercial petitgrain oil. Methods: Identification of chemical components of the petitgrain oil was performed by gas chromatography (GC. The minimum inhibitory concentrations (MIC and minimum bactericidal/fungicidal concentrations (MBC/MFC were determined using macrodilution method for the reference strains of bacteria and fungi. Results: Twenty components were identified. The petitgrain oil contained mostly oxygenated monoterpene hydrocarbons (98.01%, and the main components included linalyl acetate (48.06% and linalool (26.88%. The MIC/MBC of the petitgrain oil for bacteria was in the range of 0.63-5.0/1.25-5.0 mg/ml and for fungi in the range of 1.25-40/5.0-80 mg/ml. Conclusion: The petitgrain oil had higher antibacterial activity than antifungal activity. Bacillus subtilis among the tested bacteria and Aspergillus niger and Penicillium expansum among the fungi were found to be highly inhibited by the petitgrain oil.

  1. Dittrichia graveolens (L.) Greuter Essential Oil: Chemical Composition, Multivariate Analysis, and Antimicrobial Activity.

    Science.gov (United States)

    Mitic, Violeta; Stankov Jovanovic, Vesna; Ilic, Marija; Jovanovic, Olga; Djordjevic, Aleksandra; Stojanovic, Gordana

    2016-01-01

    The chemical composition and in vitro antimicrobial activities of Dittrichia graveolens (L.) Greuter essential oil was studied. Moreover, using agglomerative hierarchical cluster (AHC) and principal component analyses (PCA), the interrelationships of the D. graveolens essential-oil profiles characterized so far (including the sample from this study) were investigated. To evaluate the chemical composition of the essential oil, GC-FID and GC/MS analyses were performed. Altogether, 54 compounds were identified, accounting for 92.9% of the total oil composition. The D. graveolens oil belongs to the monoterpenoid chemotype, with monoterpenoids comprising 87.4% of the totally identified compounds. The major components were borneol (43.6%) and bornyl acetate (38.3%). Multivariate analysis showed that the compounds borneol and bornyl acetate exerted the greatest influence on the spatial differences in the composition of the reported oils. The antimicrobial activity against five bacterial and one fungal strain was determined using a disk-diffusion assay. The studied essential oil was active only against Gram-positive bacteria. Copyright © 2016 Verlag Helvetica Chimica Acta AG, Zürich.

  2. Chemical Composition and Antimicrobial Activities of the Essential Oil From Salvia mirzayanii Leaves.

    Science.gov (United States)

    Zomorodian, Kamiar; Moein, Mahmoodreza; Pakshir, Keyvan; Karami, Forough; Sabahi, Zahra

    2017-10-01

    Resistance of many pathogens to available drugs is a global challenge and is leading to growing interest in natural alternative products. In this study, chemical composition and in vitro antibacterial and antifungal activities of the essential oil from Salvia mirzayanii were investigated. The chemical constituents of essential oil from S mirzayanii were analyzed by gas chromatography-mass spectrometry. The antimicrobial activity was determined by broth microdilution. The main identified compounds were 1,8-cineole (41.2 ± 1.3%), linalool acetate (11.0 ± 0.5%), and α-terpinyl acetate (6.0 ± 0.4%) (mL of essential oil/g of plant material). The MIC 95 were 0.03 to 0.5 µL/mL and 16 to 128 µL/mL for gram-positive and gram-negative bacteria, respectively. These results indicated that Salvia mirzayanii essential oil significantly inhibited the growth of standard and clinically isolated tested yeasts by MIC 50 0.03 to 1 µL/mL. Potent antibacterial and antifungal activities of Salvia mirzayanii essential oil may be considered in future study, particularly against antibiotic-resistant cases.

  3. Chemical composition and antioxidant activities of essential oils from different parts of the oregano.

    Science.gov (United States)

    Han, Fei; Ma, Guang-Qiang; Yang, Ming; Yan, Li; Xiong, Wei; Shu, Ji-Cheng; Zhao, Zhi-Dong; Xu, Han-Lin

    This research was undertaken in order to characterize the chemical compositions and evaluate the antioxidant activities of essential oils obtained from different parts of the Origanum vulgare L. It is a medicinal plant used in traditional Chinese medicine for the treatment of heat stroke, fever, vomiting, acute gastroenteritis, and respiratory disorders. The chemical compositions of the three essential oils from different parts of the oregano (leaves-flowers, stems, and roots) were identified by gas chromatography-mass spectrometry (GC-MS). The antioxidant activity of each essential oil was assessed using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay and reducing the power test. Among the essential oils from different parts of the oregano, the leaf-flower oils have the best antioxidant activities, whereas the stem oils are the worst. The results of the DPPH free radical scavenging assay showed that the half maximal inhibitory concentration (IC 50 ) values of the essential oils were (0.332±0.040) mg/ml (leaves-flowers), (0.357±0.031) mg/ml (roots), and (0.501±0.029) mg/ml (stems), respectively. Interestingly, the results of reducing the power test also revealed that when the concentration exceeded 1.25 mg/ml, the leaf-flower oils had the highest reducing power; however, the stem oils were the lowest.

  4. Tuning the chemical activity through PtAu nanoalloying: a first principles study

    KAUST Repository

    Mokkath, Junais Habeeb

    2013-06-21

    The electronic structure and adsorption properties of 1.5 nm sized Pt, Au, and PtAu nanoclusters are studied by density functional theory. We explain the recent experimental finding that 20% Au content in PtAu nanoparticles is optimal to induce a dramatically different catalytic behavior. Our results show that the d-band center together with the density of states at the Fermi energy can be used as an indicator of the chemical activity of PtAu nanoclusters. The most favorable adsorption sites on the cluster surfaces as a function of the Pt/Au ratio are identified using atomic H as a probe.

  5. Chemical variability and antioxidant activity of the leaves of chosen highbush blueberry (Vaccinium corymbosum L. cultivars

    Directory of Open Access Journals (Sweden)

    Małgorzata Janiuk

    2013-04-01

    Full Text Available The paper deals with the chemical composition and antioxidant activity of aqueous extracts from leaves of two highbush blueberry varieties: ‘Bluecrop’ and ‘Northland’. The study revealed differences in the content of the analyzed components. Leaves of cv. ‘Bluecrop’ were characterized by a higher content of chlorophyll, flavonoids and anthocyanins, while the leaves of cv. ‘Northland’ contained more reducing sugars and total phenolic acids, tannins, and essential oils. Capacity of neutralizing the free radicals (DPPH in leaves of both tested cultivars was found at comparable levels.

  6. Design and Activation of a LOX/GH Chemical Steam Generator

    Science.gov (United States)

    Saunders, G. P.; Mulkey, C. A.; Taylor, S. A.

    2009-01-01

    The purpose of this paper is to give a detailed description of the design and activation of the LOX/GH fueled chemical steam generator installed in Cell 2 of the E3 test facility at Stennis Space Center, MS (SSC). The steam generator uses a liquid oxygen oxidizer with gaseous hydrogen fuel. The combustion products are then quenched with water to create steam at pressures from 150 to 450 psig at temperatures from 350 to 750 deg F (from saturation to piping temperature limits).

  7. Terpenoids in Buddleja: relevance to chemosystematics, chemical ecology and biological activity.

    Science.gov (United States)

    Houghton, Peter J; Mensah, Abraham Y; Iessa, Noha; Hong, Liao Yong

    2003-09-01

    The terpenoids reported from Buddleja species are described. The antifungal activity of chloroform extracts of B. cordata and B. davidii stembark against the soil fungi Fusarium culmorum and Sordari fimicola is reported, with buddledin A shown to be the major compound responsible. The terpenoids present support the view that the Buddlejaceae should be classified in a taxon with Scrophulariaceae rather than Loganiaceae. Ecological aspects of the terpenoids are considered in relation to insects and soil fungi and the role of terpenoids in the chemical basis of the use of Buddleja in traditional medicine is also discussed, especially with regard to their anti-inflammatory properties.

  8. A comparison between oxidation of activated carbon by electrochemical and chemical treatments

    OpenAIRE

    Berenguer, Raúl; Marco-Lozar, Juan Pablo; Quijada tomás, Cesar; Cazorla-Amoros, Diego; Morallón, Emilia

    2012-01-01

    The anodic oxidation of a granular activated carbon (GAC) in NaCl solution has been studied. The influence of the electrocatalyst-anode material, applied current and time of treatment on both the surface chemistry and porous texture properties of the GAC has been analyzed. For comparison purposes, the same GAC has been treated with three of the classical chemical oxidants: HNO 3, H 2O 2 and (NH 4) 2S 2O 8 at different concentrations and for different times. Results show that the anodic treatm...

  9. Tuning the chemical activity through PtAu nanoalloying: a first principles study

    KAUST Repository

    Mokkath, Junais Habeeb; Schwingenschlö gl, Udo

    2013-01-01

    The electronic structure and adsorption properties of 1.5 nm sized Pt, Au, and PtAu nanoclusters are studied by density functional theory. We explain the recent experimental finding that 20% Au content in PtAu nanoparticles is optimal to induce a dramatically different catalytic behavior. Our results show that the d-band center together with the density of states at the Fermi energy can be used as an indicator of the chemical activity of PtAu nanoclusters. The most favorable adsorption sites on the cluster surfaces as a function of the Pt/Au ratio are identified using atomic H as a probe.

  10. Chemical Composition and Possible in Vitro Phytotoxic Activity of Helichrsyum italicum (Roth Don ssp. italicum

    Directory of Open Access Journals (Sweden)

    Vincenzo De Feo

    2011-09-01

    Full Text Available The chemical composition of the essential oil of Helichrysum italicum (Roth Don ssp. italicum, collected in the National Park of Cilento and Diano Valley, Southern Italy, was studied by means of GC and GC/MS. Forty four compounds of 45 constituents were identified in the oil, mainly oxygenated sesquiterpenes. The essential oil was evaluated for its potential in vitro phytotoxic activity against germination and early radicle elongation of radish and garden cress. The radicle elongation of radish was significantly inhibited at the highest doses tested, while germination of both seeds was not affected.

  11. Determination of mercury in ppb level by activation analysis and chemical separation

    International Nuclear Information System (INIS)

    Requejo, C.S.

    1983-02-01

    A method for determining mercury in steel samples was developed. Activation analysis using thermal neutrons, followed by radiochemical separations to eliminate 75 Se interferences, were applied. Sixty hours after the end of the irradiation, the samples were processed and distillation of mercury and selenium bromides were carried out. Selenium was separated as an element and mercury sulfide was precipitaded. The chemical separation procedure was tested by using a tracer technique; the recovery yield was 99,2% + - 2,7%. (C.L.B.) [pt

  12. The biological activities and chemical composition of Pereskia species (Cactaceae)--a review.

    Science.gov (United States)

    Pinto, Nícolas de Castro Campos; Scio, Elita

    2014-09-01

    The exploration of nature as a source of sustainable, novel bioactive substances continues to grow as natural products play a significant role in the search for new therapeutic and agricultural agents. In this context, plants of the genus Pereskia (Cactaceae) have been studied for their biological activities, and are evolving as an interesting subject in the search for new, bioactive compounds. These species are commonly used as human foodstuffs and in traditional medicine to treat a variety of diseases. This review focuses on the bioactivity and chemical composition of the genus Pereskia, and aims to stimulate further studies on the chemistry and biological potential of the genus.

  13. Low dose effects and non-monotonic dose responses for endocrine active chemicals: Science to practice workshop: Workshop summary

    DEFF Research Database (Denmark)

    Beausoleil, Claire; Ormsby, Jean-Nicolas; Gies, Andreas

    2013-01-01

    A workshop was held in Berlin September 12–14th 2012 to assess the state of the science of the data supporting low dose effects and non-monotonic dose responses (“low dose hypothesis”) for chemicals with endocrine activity (endocrine disrupting chemicals or EDCs). This workshop consisted of lectu...

  14. Body composition of two human cadavers by neutron activation and chemical analysis

    International Nuclear Information System (INIS)

    Knight, G.S.; Beddoe, A.H.; Streat, S.J.; Hill, G.L.

    1986-01-01

    In vivo neutron activation analysis (NAA) is currently used to measure body composition in metabolic and nutritional studies in many clinical situations, but has not previously been validated by comparison with chemical analysis of human cadavers. Total body nitrogen (TBN) and chlorine (TBCl) were measured in two human cadavers by NAA before homogenization and chemical analysis (CHEM) after (cadaver 1: TBN, 1.47 NAA, 1.51 CHEM; TBCl, 0.144 NAA, 0.147 CHEM; cadaver 2: TBN, 0.576 NAA, 0.572 CHEM; TBCl, 0.0227 NAA, 0.0250 CHEM). The homogenates were also analyzed by NAA, and no significant differences were found, indicating that the effects of elemental inhomogeneity on the measurement of TBN and TBCl are insignificant. Total body water, fat, protein, minerals, and carbohydrates were measured chemically for each cadaver and compared with estimates for these compartments obtained from a body composition model, which when used in vivo involves NAA and tritium dilution. The agreement found justifies the use of the model for the measurement of changes in total body protein, water, and fat in sequential studies in groups of patients

  15. Chemical characterization of ancient pottery from the southwest Amazonia using neutron activation analysis

    International Nuclear Information System (INIS)

    Carvalho, Patricia R.; Munita, Casimiro S.; Neves, Eduardo G.; Zimpel, Carlos A.; Universidade de Sao Paulo

    2017-01-01

    The analyzes carried out in this work aims to contribute to the discussion about the ceramic objects founded in Monte Castelo's sambaqui located at Southwest Amazonia. The first study accomplished by Miller in 1980 suggests that this archaeological site is inserted in the old contexts of production of ceramics in the Amazon. Until today, there are not any physical and chemical analysis studies in this ceramics and this kind of studies may help archaeological studies performed at the sambaqui. With this purpose, this work presents a preliminary study of chemical characterization of eighty-seven ceramic samples using the Neutron Activation Analysis (NAA). The analyzed elements were: As, K, La, Lu, Na, Nd, Sm, U, Yb, Ce, Co, Cr, Cs, Eu, Fe, Hf, Rb, Sc, Ta, Tb, Th. With the purpose to study the similarity/dissimilarity between the samples cluster and discriminant analysis were used. The results showed the existence of three different chemical groups that are in agreement with the archaeological studies made by Miller which found a sequence of cultural development, with three main occupational components whose dating ranging from 8.400 to 4.000 b.P. In this way, the results of this work are in agreement with miller's studies and suggest Bacabal's phase as the oldest ceramist culture in the Southwest of the Amazon. (author)

  16. Chemical Profile and Antioxidant Activity of the Oil from Peony Seeds (Paeonia suffruticosa Andr.

    Directory of Open Access Journals (Sweden)

    Xin Yang

    2017-01-01

    Full Text Available Peony seed oil (PSO is a novel vegetable oil developed from the seeds of Paeonia suffruticosa Andr. The present study aimed to make an overall investigation on the chemical profile and antioxidant activities of PSO for reasonable development and utilization of this new resource food. Chemical analysis revealed that PSO was characterized by an uncommon high portion of α-linolenic acid (>38%, fairly low ratio of n-6 to n-3 polyunsaturated fatty acids (0.69, and much higher content of γ-tocopherol than various conventional seed oils. In vitro assay indicated that PSO is a more potent scavenger of free radicals than extra virgin olive oil. Moderate intake of PSO exhibited obvious protection against various oxidative damages such as tetrachloromethane-induced acute liver injury in mice and diet-induced hyperlipidemia in rats. The changes in the key indicators of oxidative injury and fatty acid composition in the liver caused by PSO administration were measured, and the results demonstrated that antioxidant properties of PSO are closely related to their characteristic chemical composition. Consequently, the present study provided new evidence for the health implications of PSO, which deserves further development for medical and nutritional use against oxidative damages that are associated with various diseases.

  17. Micro-poromechanics model of fluid-saturated chemically active fibrous media.

    Science.gov (United States)

    Misra, Anil; Parthasarathy, Ranganathan; Singh, Viraj; Spencer, Paulette

    2015-02-01

    We have developed a micromechanics based model for chemically active saturated fibrous media that incorporates fiber network microstructure, chemical potential driven fluid flow, and micro-poromechanics. The stress-strain relationship of the dry fibrous media is first obtained by considering the fiber behavior. The constitutive relationships applicable to saturated media are then derived in the poromechanics framework using Hill's volume averaging. The advantage of this approach is that the resultant continuum model accounts for the discrete nature of the individual fibers while retaining a form suitable for porous materials. As a result, the model is able to predict the influence of micro-scale phenomena, such as the fiber pre-strain caused by osmotic effects and evolution of fiber network structure with loading, on the overall behavior and in particular, on the poromechanics parameters. Additionally, the model can describe fluid-flow related rate-dependent behavior under confined and unconfined conditions and varying chemical environments. The significance of the approach is demonstrated by simulating unconfined drained monotonic uniaxial compression under different surrounding fluid bath molarity, and fluid-flow related creep and relaxation at different loading-levels and different surrounding fluid bath molarity. The model predictions conform to the experimental observations for saturated soft fibrous materials. The method can potentially be extended to other porous materials such as bone, clays, foams and concrete.

  18. First satellite measurements of chemical changes in coincidence with sprite activity

    Science.gov (United States)

    Arnone, Enrico; São Sabbas, Fernanda; Kero, Antti; Soula, Serge; Carlotti, Massimo; Chanrion, Olivier; Dinelli, Bianca Maria; Papandrea, Enzo; Castelli, Elisa; Neubert, Torsten

    2010-05-01

    The last twenty years have seen the discovery of electric discharges in the Earth's atmosphere above thunderstorms, the so-called sprites and jets. It has been suggested that they impact the atmospheric chemistry and possibly affect the ozone layer through their repeated occurrence. Whereas theoretical studies and laboratory experiments suggest enhancement of such gasses as nitrogen oxides by up to hundreds of percent within sprites, a definitive detection of their chemical effects have to date been unsuccessful. In this paper, we report on the first measurements of atmospheric chemical perturbations recorded in coincidence with sprite activity. A striking event occurred on 25 August 2003 when the MIPAS spectrometer onboard the Envisat satellite recorded spectroscopic measurements soon after a sequence of 11 sprites observed above Corsica (France) by Eurosprite ground facilities (details of the convective system are discussed in a companion paper by São Sabbas et al.). The measurements show an enhancement of ambient nitrous oxide by 80% at 52 km altitude in the region above the parent thunderstorm. The recorded chemical changes imply sprites can exert significant modification of the atmospheric chemistry at a regional scale, confirming model and laboratory predictions of sprite-chemistry, and requiring a new estimate of their global impact. The results of the analysis and their implications are discussed.

  19. Chemical characterization of ancient pottery from the southwest Amazonia using neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Patricia R.; Munita, Casimiro S.; Neves, Eduardo G.; Zimpel, Carlos A., E-mail: camunita@ipen.br, E-mail: edgneves@usp.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Universidade de Sao Paulo (MAE/USP), SP (Brazil). Museu de Arqueologia e Etnologia

    2017-11-01

    The analyzes carried out in this work aims to contribute to the discussion about the ceramic objects founded in Monte Castelo's sambaqui located at Southwest Amazonia. The first study accomplished by Miller in 1980 suggests that this archaeological site is inserted in the old contexts of production of ceramics in the Amazon. Until today, there are not any physical and chemical analysis studies in this ceramics and this kind of studies may help archaeological studies performed at the sambaqui. With this purpose, this work presents a preliminary study of chemical characterization of eighty-seven ceramic samples using the Neutron Activation Analysis (NAA). The analyzed elements were: As, K, La, Lu, Na, Nd, Sm, U, Yb, Ce, Co, Cr, Cs, Eu, Fe, Hf, Rb, Sc, Ta, Tb, Th. With the purpose to study the similarity/dissimilarity between the samples cluster and discriminant analysis were used. The results showed the existence of three different chemical groups that are in agreement with the archaeological studies made by Miller which found a sequence of cultural development, with three main occupational components whose dating ranging from 8.400 to 4.000 b.P. In this way, the results of this work are in agreement with miller's studies and suggest Bacabal's phase as the oldest ceramist culture in the Southwest of the Amazon. (author)

  20. Essential Oil from the Resin of Protium heptaphyllum: Chemical Composition, Cytotoxicity, Antimicrobial Activity, and Antimutagenicity.

    Science.gov (United States)

    de Lima, Ewelyne Miranda; Cazelli, Didley Sâmia Paiva; Pinto, Fernanda Endringer; Mazuco, Renata Alves; Kalil, Ieda Carneiro; Lenz, Dominik; Scherer, Rodrigo; de Andrade, Tadeu Uggere; Endringer, Denise Coutinho

    2016-01-01

    Protium heptaphyllum (Aubl.) March is popularly used as an analgesic and anti-inflammatory agent. This study aimed to evaluate the chemical composition of P. heptaphyllum essential oil, its cytotoxicity in a breast cancer cell line (MCF-7), antimicrobial activity, and its antimutagenicity in vivo. The chemical composition of the essential oil collected in three 3 years was determined by gas chromatography-mass spectrometry. The cytotoxicity was evaluated using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Annexin V conjugated with fluorescein isothiocyanate, caspase-3, and tumor necrosis factor-alpha (TNF-α) assays were performed to evaluate apoptosis and inflammatory events. The antimutagenic activity at doses of 25, 50, and 100 mg/kg was determined using a micronucleus test in murine bone marrow. The essential oil showed a predominance of monoterpene compounds, being the terpinolene, p-cymene-8-ol, and p-cymene, present in the essential oil extracted in the 3 years. The essential oil showed a protection against cyclophosphamide-induced genotoxicity, and the cytotoxicity index polychromatic erythrocytes/normochromatic erythrocytes ratio in animals treated with oil at all doses (1.34 ± 0.33; 1.15 ± 0.1; 1.11 ± 0.13) did not differ from the negative control animal (1.31 ± 0.33), but from the cyclophosphamide group (0.61 ± 0.12). Cytotoxicity, at a concentration of 40.0 μg/mL, and antimicrobial activity were not observed for the essential oil (minimum inhibitory concentration ≥0.5 mg/mL). The essential oil did not change the levels of caspase-3 in the TNF-α level. The essential oil showed antimutagenic activity due to its chemical composition. Terpinolene, p-cymene-8-ol, and p-cymene are the main constituents of the essential oil of P. heptaphyllum collected within 3-yearsThe essential oil of P. heptaphyllum did not show antimicrobial activity (MIC >0.5 mg/mL) against E. coli, S. aureus, E. faecalis, and C. albicansThe essential oil

  1. Effect of Heterogeneous Chemical Reactions on the Köhler Activation of Aqueous Organic Aerosols.

    Science.gov (United States)

    Djikaev, Yuri S; Ruckenstein, Eli

    2018-05-03

    We study some thermodynamic aspects of the activation of aqueous organic aerosols into cloud droplets considering the aerosols to consist of liquid solution of water and hydrophilic and hydrophobic organic compounds, taking into account the presence of reactive species in the air. The hydrophobic (surfactant) organic molecules on the surface of such an aerosol can be processed by chemical reactions with some atmospheric species; this affects the hygroscopicity of the aerosol and hence its ability to become a cloud droplet either via nucleation or via Köhler activation. The most probable pathway of such processing involves atmospheric hydroxyl radicals that abstract hydrogen atoms from hydrophobic organic molecules located on the aerosol surface (first step), the resulting radicals being quickly oxidized by ubiquitous atmospheric oxygen molecules to produce surface-bound peroxyl radicals (second step). These two reactions play a crucial role in the enhancement of the Köhler activation of the aerosol and its evolution into a cloud droplet. Taking them and a third reaction (next in the multistep chain of relevant heterogeneous reactions) into account, one can derive an explicit expression for the free energy of formation of a four-component aqueous droplet on a ternary aqueous organic aerosol as a function of four independent variables of state of a droplet. The results of numerical calculations suggest that the formation of cloud droplets on such (aqueous hydrophilic/hydrophobic organic) aerosols is most likely to occur as a Köhler activation-like process rather than via nucleation. The model allows one to determine the threshold parameters of the system necessary for the Köhler activation of such aerosols, which are predicted to be very sensitive to the equilibrium constant of the chain of three heterogeneous reactions involved in the chemical aging of aerosols.

  2. 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.

  3. Thermal analysis of physical and chemical changes occuring during regeneration of activated carbon

    Directory of Open Access Journals (Sweden)

    Radić Dejan B.

    2017-01-01

    Full Text Available High-temperature thermal process is a commercial way of regeneration of spent granular activated carbon. The paper presents results of thermal analysis conducted in order to examine high-temperature regeneration of spent activated carbon, produced from coconut shells, previously used in drinking water treatment. Results of performed thermogravimetric analysis, derivative thermogravimetric analysis, and differential thermal analysis, enabled a number of hypotheses to be made about different phases of activated carbon regeneration, values of characteristic parameters during particular process phases, as well as catalytic impact of inorganic materials on development of regeneration process. Samples of activated carbon were heated up to 1000°C in thermogravimetric analyser while maintaining adequate oxidizing or reducing conditions. Based on diagrams of thermal analysis for samples of spent activated carbon, temperature intervals of the first intense mass change phase (180-215°C, maximum of exothermic processes (400-450°C, beginning of the second intense mass change phase (635-700°C, and maximum endothermic processes (800-815°C were deter-mined. Analysing and comparing the diagrams of thermal analysis for new, previously regenerated and spent activated carbon, hypothesis about physical and chemical transformations of organic and inorganic adsorbate in spent activated carbon are given. Transformation of an organic adsorbate in the pores of activated carbon, results in loss of mass and an exothermic reaction with oxygen in the vapour phase. The reactions of inorganic adsorbate also result the loss of mass of activated carbon during its heating and endothermic reactions of their degradation at high temperatures.

  4. Chemical composition and antibacterial activity of Pinus halepensis Miller growing in West Northern of Algeria

    Directory of Open Access Journals (Sweden)

    Nadia Fekih

    2014-04-01

    Full Text Available Objective: To find new bioactive natural products, the chemical composition and to sudy the antibacterial activity of essential oil components extracted from the aerial parts of the Algerian aromatic plant Pinus halepensis Miller (P. halepensis (needles, twigs and buds. Methods: The essential oil used in this study was isolated by hydrodistillation using a Clevenger-type apparatus according to the European Pharmacopoeia. The chemical composition was investigated using GC-retention indices (RI and GC-MS. Results: Forty-nine compounds, representing 97.9% of the total collective oil, were identified. Essential oil was dominated by hydrocarbon compounds (80.6% especially monoterpenes (65.5%. The major compounds from ten oils stations were: myrcene (15.2%-32.0%, α-pinene (12.2%- 24.5%, E-β-caryophyllene (7.0%-17.1%, terpinolene (1.8%-13.3%, 2-phenyl ethyl isovalerate (4.8%-10.9%, terpinene-4-ol (1.0%-8.2 % and sabinene (1.5%-6.3%. The intra-species variations of the chemical compositions of P. halepensis aerial parts essential oils from ten Algerian sample locations were investigated using statistical analysis. Essential oil samples were clustered in 2 groups by hierarchical cluster analysis, according to their chemical composition. The essential oil revealed an interesting antimicrobial effect against Lysteria monocytogenes, Enterococcus faecalis, Pseudomonas aeruginosa, Acinetobacter baumanii, Citrobacter freundii and Klebsiella pneumoniae. Conclusions: These results suggest that the essential oil from P. halepensis may be a new potential source as natural antimicrobial applied in pharmaceutical and food industries.

  5. Chemical composition and antibacterial activity of Pinus halepensis Miller growing in West Northern of Algeria

    Science.gov (United States)

    Fekih, Nadia; Allali, Hocine; Merghache, Salima; Chaïb, Faïza; Merghache, Djamila; El Amine, Mohamed; Djabou, Nassim; Muselli, Alain; Tabti, Boufeldja; Costa, Jean

    2014-01-01

    Objective To find new bioactive natural products, the chemical composition and to sudy the antibacterial activity of essential oil components extracted from the aerial parts of the Algerian aromatic plant Pinus halepensis Miller (P. halepensis) (needles, twigs and buds). Methods The essential oil used in this study was isolated by hydrodistillation using a Clevenger-type apparatus according to the European Pharmacopoeia. The chemical composition was investigated using GC-retention indices (RI) and GC-MS. Results Forty-nine compounds, representing 97.9% of the total collective oil, were identified. Essential oil was dominated by hydrocarbon compounds (80.6%) especially monoterpenes (65.5%). The major compounds from ten oils stations were: myrcene (15.2%-32.0%), α-pinene (12.2%-24.5%), E-β-caryophyllene (7.0%-17.1%), terpinolene (1.8%-13.3%), 2-phenyl ethyl isovalerate (4.8%-10.9%), terpinene-4-ol (1.0%-8.2 %) and sabinene (1.5%-6.3%). The intra-species variations of the chemical compositions of P. halepensis aerial parts essential oils from ten Algerian sample locations were investigated using statistical analysis. Essential oil samples were clustered in 2 groups by hierarchical cluster analysis, according to their chemical composition. The essential oil revealed an interesting antimicrobial effect against Lysteria monocytogenes, Enterococcus faecalis, Pseudomonas aeruginosa, Acinetobacter baumanii, Citrobacter freundii and Klebsiella pneumoniae. Conclusions These results suggest that the essential oil from P. halepensis may be a new potential source as natural antimicrobial applied in pharmaceutical and food industries.

  6. Chemical composition and biological activity of essential oils of Dracocephalum heterophyllum and Hyssopus officinalis from Western Himalaya

    Science.gov (United States)

    The essential oils of two representatives of the Lamiaceae-family, Dracocephalum heterophyllum Benth. and Hyssopus officinalis L., are described for their antifungal, antibacterial and larvicidal as well as biting deterrent activities. Additionally, the essential oils’ chemical compositions, analyze...

  7. Selective small-chemical inhibitors of protein arginine methyltransferase 5 with anti-lung cancer activity.

    Directory of Open Access Journals (Sweden)

    Gui-Mei Kong

    Full Text Available Protein arginine methyltransferase 5 (PRMT5 plays critical roles in a wide variety of biological processes, including tumorigenesis. By screening a library of small chemical compounds, we identified eight compounds that selectively inhibit the PRMT5 enzymatic activity, with IC50 values ranging from 0.1 to 6 μM. Molecular docking simulation and site-directed mutagenesis indicated that identified compounds target the substrate-binding site in PRMT5. Treatment of lung cancer cells with identified inhibitors led to inhibition of the symmetrical arginine methylation of SmD3 and histones and the cellular proliferation. Oral administration of the inhibitor demonstrated antitumor activity in a lung tumor xenograft model. Thus, identified PRMT5-specific small-molecule inhibitors would help elucidate the biological roles of PRMT5 and serve as lead compounds for future drug development.

  8. Chemical Composition, Antioxidant and Antimicrobial Activity of Pericarpium Citri Reticulatae Essential Oil

    Directory of Open Access Journals (Sweden)

    Bei Gao

    2011-05-01

    Full Text Available The chemical composition, antioxidant and antimicrobial activity of Pericarpium Citri Reticulatae (PCR essential oil obtained using an improved Clevenger type apparatus were studied. Among the five different PCRs examined the highest yield of essential oil was found in Chachi 2004 (harvested and stored in 2004 and the lowest in Chachi 2008 (harvested and stored in 2008. Fifty three different volatile compounds were determined, including terpenic hydrocarbons, alcohols, aldehydes, ketones and esters. D-limonene, one of terpenes, was the major constituent in PCR. The antioxidant capacity of PCR essential oil varied considerably with the duration of storage time, and the oil from Chachi 1994 has the strongest ferric-reducing antioxidant power. In addition, the essential oil possessed varying degrees of antimicrobial activity against Gram-positive bacteria (Staphylococcus aureus, Bacillus subtilis, Bacillus cereus, except Streptococcus faecalis, while had no effect on Gram-negative bacteria (Escherichia coli, Enterobacter cloacae.

  9. Decontamination of adsorbed chemical warfare agents on activated carbon using hydrogen peroxide solutions.

    Science.gov (United States)

    Osovsky, Ruth; Kaplan, Doron; Nir, Ido; Rotter, Hadar; Elisha, Shmuel; Columbus, Ishay

    2014-09-16

    Mild treatment with hydrogen peroxide solutions (3-30%) efficiently decomposes adsorbed chemical warfare agents (CWAs) on microporous activated carbons used in protective garments and air filters. Better than 95% decomposition of adsorbed sulfur mustard (HD), sarin, and VX was achieved at ambient temperatures within 1-24 h, depending on the H2O2 concentration. HD was oxidized to the nontoxic HD-sulfoxide. The nerve agents were perhydrolyzed to the respective nontoxic methylphosphonic acids. The relative rapidity of the oxidation and perhydrolysis under these conditions is attributed to the microenvironment of the micropores. Apparently, the reactions are favored due to basic sites on the carbon surface. Our findings suggest a potential environmentally friendly route for decontamination of adsorbed CWAs, using H2O2 without the need of cosolvents or activators.

  10. Chemical composition and antioxidant activity of essential oils of Deverra scoparia Coss. & Dur. (Apiaceae)

    International Nuclear Information System (INIS)

    Hammoudi, R.; Dehak, K.; Hadj Mahammed, M.; Didi Ouldelhadj, M.

    2015-01-01

    This study aimed to determine the chemical composition and to evaluate the antioxidant activity of the essential oils of the aerial part of the plant Deverra scoparia Coss. &Dur. The extraction of essential oils was carried out by hydrodistillation. The composition of essential oils was analyzed by gas chromatography coupled with mass spectrometry (GC and GC/MS). 22 constituents were identified, representing 84.63% of the essential oil. The major compounds are: α-bornyl acetate (31.99%) andα-pinene (12.05%). The study of the antioxidant power of these oils was performed by the method of DPPH and ABTS. The results showed that antioxidant activity of the Deverra scoparia essential oil wasmore effective than the two references tested,ascorbic acidand Trolox (author)

  11. Chemical activation of tea waste and use for the removal of chromium (Vi) from aqueous solution

    International Nuclear Information System (INIS)

    Qureshi, K.; Bhatti, I.; Ansari, A.K.

    2009-01-01

    Tea waste is the residue left after the preparation of tea. At present the tea waste is regarded as a waste product having no use. In this study, tea waste is converted into an adsorbent. Tea waste is chemically activated with phosphoric acid at low temperature 450 degree C. This activated carbon is then utilized as an adsorbent for the removal of Chromium (VI) from aqueous solution. The various sorption parameters i.e pH, sorbent dose sorbate concentration, shaking time and shaking speed are first optimized. 75% of chromium from aqueous solution is effectively removed at pH 2. The best optimum conditions were obtained when 1 gm of sorbent was agitated at 100 rpm with 60 mg/l of sorbate for 50 minutes. Better results were obtained when low concentrations of sorbates were used. Hence tea waste could also be successfully used for the sorption of Chromium (VI), from industrial waste water. (author)

  12. Chemical Characterization and Cytotoxic Activity of Blueberry Extracts (cv. Misty) Cultivated in Brazil.

    Science.gov (United States)

    Massarotto, Giovana; Barcellos, Thiago; Garcia, Charlene Silvestrin Celi; Brandalize, Ana Paula Carneiro; Moura, Sidnei; Schwambach, Joséli; Henriques, João Antonio Pêgas; Roesch-Ely, Mariana

    2016-08-01

    Vaccinium corymbosum (L.) varieties cultivation is relatively recent in Brazil, but its production has been intensified given its good adaptability to the Southern Brazil climate. Blueberries are a rich source of phenolic compounds and contain significant levels of anthocyanins, flavonols, chlorogenic acids, and procyanidins, which lead to different biological activities. Chemical identification of skin and whole hydroalcoholic blueberry extracts (ExtSB and ExtWB) revealed the presence of anthocyanins concentrated in the skin and others chemicals compounds as quercetin glycosides, proanthocyanins dimers, citric, and chlorogenic acid in the pulp. Selectivity for tumor cell lines (Hep-2, HeLa, HT-29) using ExtSB and ExtWB extracts was observed through MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay after 24 h of treatment when compared to nontumor cells (MRC-5). Morphological changes and late stages of apoptotic and necrosis process were seen in HT-29 cell line after ExtWB treatment, compared to nontumor cell line MRC-5. These results are in agreement with other studies that indicate the activity of compounds such as anthocyanins and other molecules found in Southern Highbush blueberry variety, attributed to promote beneficial effects on health that may respond as cytotoxic natural agent and contribute to cancer treatment. © 2016 Institute of Food Technologists®

  13. Antioxidant Activity of a Geopropolis from Northeast Brazil: Chemical Characterization and Likely Botanical Origin.

    Science.gov (United States)

    Ferreira, Joselena M; Fernandes-Silva, Caroline C; Salatino, Antonio; Message, Dejair; Negri, Giuseppina

    2017-01-01

    Geopropolis is a product containing wax, plant resin, and soil particles. It is elaborated by stingless bees of tribe Meliponini. Methanol extracts of sample of geopropolis produced by Scaptotrigona postica ("mandaguari") in the state of Rio Grande do Norte (RN, northeast Brazil) were analyzed for the determination of standard parameters (total phenols, total flavonoids, and radical scavenging activity) and chemical characterization by HPLC-DAD-MS/MS analysis. The sample analyzed has high contents of total phenols and flavonoids, as well as high antioxidant activity. The constituents characterized were mainly flavonols, such as quercetin methyl ethers, and methoxychalcones. Such chemical profile is similar to the composition of a green propolis from the same area of RN, which is produced by Africanized Apis mellifera , using shoot apices of Mimosa tenuiflora , popularly known as "jurema-preta." This finding provides evidence that "mandaguari" geopropolis and honeybee propolis have the same botanical origin in RN. The sharing of a plant resin source by phylogenetically distant bees (Apinae and Meliponinae) suggests that bee genetic factors play little role in the choice of plants for resin collection and that the availability of potential botanical sources plays a decisive role.

  14. Production of bioelectricity, bio-hydrogen, high value chemicals and bioinspired nanomaterials by electrochemically active biofilms.

    Science.gov (United States)

    Kalathil, Shafeer; Khan, Mohammad Mansoob; Lee, Jintae; Cho, Moo Hwan

    2013-11-01

    Microorganisms naturally form biofilms on solid surfaces for their mutual benefits including protection from environmental stresses caused by contaminants, nutritional depletion or imbalances. The biofilms are normally dangerous to human health due to their inherited robustness. On the other hand, a recent study suggested that electrochemically active biofilms (EABs) generated by electrically active microorganisms have properties that can be used to catalyze or control the electrochemical reactions in a range of fields, such as bioenergy production, bioremediation, chemical/biological synthesis, bio-corrosion mitigation and biosensor development. EABs have attracted considerable attraction in bioelectrochemical systems (BESs), such as microbial fuel cells and microbial electrolysis cells, where they act as living bioanode or biocathode catalysts. Recently, it was reported that EABs can be used to synthesize metal nanoparticles and metal nanocomposites. The EAB-mediated synthesis of metal and metal-semiconductor nanocomposites is expected to provide a new avenue for the greener synthesis of nanomaterials with high efficiency and speed than other synthetic methods. This review covers the general introduction of EABs, as well as the applications of EABs in BESs, and the production of bio-hydrogen, high value chemicals and bio-inspired nanomaterials. Copyright © 2013 Elsevier Inc. All rights reserved.

  15. Chemical characterization and insecticidal activity of Calotropis gigantea L. flower extract against Tribolium castaneum (Herbst

    Directory of Open Access Journals (Sweden)

    Muhammad Rowshanul Habib

    2016-12-01

    Full Text Available Objective: To test the insecticidal activity of ethyl acetate extract of Calotropis gigantea L. flower (designated as EECF against stored grain pest Tribolium castaneum (Herbst of different larval and adult stages. Methods: Residual film method was used here to study the toxicity of EECF against Tribolium castaneum and gas chromatography-mass spectrometer analysis was also performed to characterize the chemicals of EECF. Results: In residual film bioassay, EECF showed lowest LD50 (0.134 mg/cm2 against 1st instar larvae of Tribolium castaneum and this finding ultimately revealed that the insect of initial stage was more susceptible than other stages. From the results of this study, it was found that with the increasing of age, Tribolium castaneum showed some extent of resistance against the toxicity of EECF. Moreover, chemical profiles of EECF identified by gas chromatography-mass spectrometer analysis were also found to consistent with its insecticidal activity. Conclusions: So, the overall results suggested that extracts of Calotropis gigantea L. flower have potential insecticidal effect which might be used in pest control.

  16. Retinyl β-glucoronide: its occurrence in human serum, chemical synthesis and biological activity

    International Nuclear Information System (INIS)

    Barua, A.B.; Batres, R.O.; Olson, J.A.

    1986-01-01

    When retinol is administered to rats, retinyl and retinoyl β-glucuronides appear in the bile. Retinyl or retinoyl β-glucuronide is also synthesized in vitro when rat liver microsomes are incubated with uridinediphosphoglucuronic acid and either retinol or retinoic acid. Retinoyl β-glucuronide, a major metabolite of retinoic acid in a number of tissues, is highly active biologically, has been chemically synthesized, and is found in human blood. The physiological significance of the glucuronides of vitamin A are not known yet. To investigate further its metabolism and possible physiological role, retinyl β-glucuronide was chemically synthesized from retinol and characterized by study of its ultra-violet spectrum (γ/sub max/ 325 nm in methanol, 329 nm in water), 1 H-NMR and mass spectra. Retinyl β-glucuronide was extensively hydrolyzed by bacterial β-glucuronidase to retinol. Retinyl β-glucuronide is soluble in water and was detected in significant amounts in the serum of healthy human adults. The biological activity of synthetic retinyl β-glucuronide was determined in rats by the rat growth bioassay method

  17. Chemical constituents, radical scavenging activity and enzyme inhibitory capacity of fruits from Cotoneaster pannosus Franch.

    Science.gov (United States)

    Les, Francisco; López, Víctor; Caprioli, Giovanni; Iannarelli, Romilde; Fiorini, Dennis; Innocenti, Marzia; Bellumori, Maria; Maggi, Filippo

    2017-05-24

    Cotoneaster pannosus (Rosaceae) is a semievergreen shrub, producing globose dark red pomes, native to China and widely used as an ornamental plant all over the world. Despite its extensive cultivation, little information is available on the chemical composition and biological activities of its fruits. In this work, the analysis of the chemical composition of C. pannosus fruits, in terms of phenolic components, carotenoids and ascorbic acid by HPLC/DAD, HPLC/ESI-MS and MS/MS as well as in terms of macro- and micro-nutrients was performed. The fruits proved to be a good source of shikimic acid and caffeoylquinic acids, whereas β-carotene, pelargonidin-3-O glucoside and cyanidin-3,5-rutinoside gave an important contribution to the color of the fruit. Both the polar and apolar fruit extracts showed noteworthy radical scavenger activity and inhibitory effects against monoamine oxidase A (MAO-A), tyrosinase (TYR) and α-glucosidase, making C. pannosus red pomes a promising candidate ingredient in functional foods and dietary supplements.

  18. Synthesis of electro-active manganese oxide thin films by plasma enhanced chemical vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Merritt, Anna R. [Energetics Research Division, Naval Air Warfare Center Weapons Division, China Lake, CA 93555 (United States); Rajagopalan, Ramakrishnan [Department of Engineering, The Pennsylvania State University, Dubois, PA 15801 (United States); Materials Research Institute, The Pennsylvania State University, University Park, PA 16802 (United States); Carter, Joshua D. [Energetics Research Division, Naval Air Warfare Center Weapons Division, China Lake, CA 93555 (United States)

    2014-04-01

    The good stability, cyclability and high specific capacitance of manganese oxide (MnO{sub x}) has recently promoted a growing interest in utilizing MnO{sub x} in asymmetric supercapacitor electrodes. Several literature reports have indicated that thin film geometries of MnO{sub x} provide specific capacitances that are much higher than bulk MnO{sub x} powders. Plasma enhanced chemical vapor deposition (PECVD) is a versatile technique for the production of metal oxide thin films with high purity and controllable thickness. In this work, MnO{sub x} thin films deposited by PECVD from a methylcyclopentadienyl manganese tricarbonyl precursor are presented and the effect of processing conditions on the quality of MnO{sub x} films is described. The film purity and oxidation state of the MnO{sub x} films were studied by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. Preliminary electrochemical testing of MnO{sub x} films deposited on carbon fiber electrodes in aqueous electrolytes indicates that the PECVD synthesized films are electrochemically active. - Highlights: • Plasma enhanced chemical vapor deposition of manganese oxide thin films. • Higher plasma power and chamber pressure increase deposition rate. • Manganese oxide thin films are electrochemically active. • Best electrochemical performance observed for pure film with low stress • Lower capacitance observed at higher scan rates despite thin film geometry.

  19. Biological effects of activation products and other chemicals released from fusion power plants

    International Nuclear Information System (INIS)

    Strand, J.A.; Poston, T.M.

    1976-09-01

    Literature reviews indicate that existing information is incomplete, often contradictory, and of questionable value for the prediction and assessment of ultimate impact from fusion-associated activation products and other chemical releases. It is still uncertain which structural materials will be used in the blanket and first wall of fusion power plants. However, niobium, vanadium, vanadium-chromium alloy, vanadium-titanium alloy, sintered aluminum product, and stainless steel have been suggested. The activation products of principal concern will be the longer-lived isotopes of 26 Al, 49 V, 51 Cr, 54 Mn, 55 Fe, 58 Co, 60 Co, 93 Nb, and 94 Nb. Lithium released to the environment either during the mining cycle, from power plant operation or accident, may be in the form of a number of compound types varying in solubility and affinity for biological organisms. The effects of a severe liquid metal fire or explosion involving Na or K will vary according to inherent abiotic and biotic features of the affected site. Saline, saline-alkaline, and sodic soils of arid lands would be particularly susceptible to alkaline stress. Beryllium released to the environment during the mining cycle or reactor accident situation could be in the form of a number of compound types. Adverse effects to aquatic species from routine chemical releases (biocides, corrosion inhibitors, dissolution products) may occur in the discharge of both fission and fusion power plant designs

  20. Determination of chemical elements in Eucalyptus grandis, manured with Ballad's, by neutrons activation analysis

    International Nuclear Information System (INIS)

    Mateus, Natalina de Fatima; Madi Filho, Tufic

    2007-01-01

    The biosolid is a mud resulting from the biological treatment of wasted liquids. It is considered as a profitable alternative and important to minimize the environmental impact generated by the sewage thrown in to sanitary lands, in forest cultures like the Eucalyptus grandis. The objective of this work was to detect which chemical elements are present in Eucalyptus grandis samples, fertilized with different quantities of biosolid. The eucalyptuses of Estacao Experimental de Ciencias Florestais of Itatinga were planted in March of 1998 and collected with five years old. The used biosolid was produced by Station of Treatment of Sewer of Barueri - SP, classified as kind B. For the determination of the presence and quantity of chemical elements in the eucalyptus samples, an analysis technique by neutronic activation (NAA) was used followed by gamma rays spectroscopy. The samples were irradiated in the Nuclear Reactor IEA-R1 of IPEN-SP, followed by the measure of induced gamma rays activity, using a Detector HPGe. The presence, mainly of Br, Mn, Na and K, was detected in all analyzed samples. (author)

  1. Removal of calcium and magnesium ions from shale gas flowback water by chemically activated zeolite.

    Science.gov (United States)

    Chang, Haiqing; Liu, Teng; He, Qiping; Li, Duo; Crittenden, John; Liu, Baicang

    2017-07-01

    Shale gas has become a new sweet spot of global oil and gas exploration, and the large amount of flowback water produced during shale gas extraction is attracting increased attention. Internal recycling of flowback water for future hydraulic fracturing is currently the most effective, and it is necessary to decrease the content of divalent cations for eliminating scaling and maintaining effectiveness of friction reducer. Zeolite has been widely used as a sorbent to remove cations from wastewater. This work was carried out to investigate the effects of zeolite type, zeolite form, activation chemical, activation condition, and sorption condition on removal of Ca 2+ and Mg 2+ from shale gas flowback water. Results showed that low removal of Ca 2+ and Mg 2+ was found for raw zeolite 4A and zeolite 13X, and the efficiency of the mixture of both zeolites was slightly higher. Compared with the raw zeolites, the zeolites after activation using NaOH and NaCl greatly improved the sorption performance, and there was no significant difference between dynamic activation and static activation. Dynamic sorption outperformed static sorption, the difference exceeding 40% and 7-70% for removal of Ca 2+ and Mg 2+ , respectively. Moreover, powdered zeolites outperformed granulated zeolites in divalent cation removal.

  2. Chemical composition and antioxidant/antimicrobial activities in supercritical carbon dioxide fluid extract of Gloiopeltis tenax.

    Science.gov (United States)

    Zheng, Jiaojiao; Chen, Yicun; Yao, Fen; Chen, Weizhou; Shi, Ganggang

    2012-12-01

    Gloiopeltis tenax (G. tenax) is widely distributed along the Chinese coastal areas and is commonly used in the treatment of diarrhea and colitis. This study aimed at investigating the bioactivities of the volatile constituents in G. tenax. We extracted the essential constituents of G. tenax by supercritical carbon dioxide extraction (CO₂-SFE), then identified and analyzed the constituents by gas chromatography-mass spectrometry (GC-MS). In total, 30 components were identified in the G. tenax extract. The components showed remarkable antioxidant activity (radical scavenging activity of 2,2-diphenyl-1-picrylhydrazyl (DPPH)), lipid peroxidation inhibition capacity (in a β-carotene/linoleic acid-coupled oxidation reaction), and hydroxyl radical-scavenging activity (by deoxyribose degradation by iron-dependent hydroxyl radical), compared to butylated hydroxytoluene. In microdilution assays, G. tenax extracts showed a moderate inhibitory effects on Staphyloccocus aureus (minimum inhibitory concentration (MIC) = 3.9 mg/mL), Enterococcus faecalis (7.8 mg/mL), Pseudomonas aeruginosa (15.6 mg/mL), and Escherichia coli (3.9 mg/mL). Antioxidant and antimicrobial activities of G. tenax were related to the active chemical composition. These results suggest that the CO₂-SFE extract from G. tenax has potential to be used as a natural antioxidant and antimicrobial agent in food processing.

  3. Chemical constituents of the essential oil, antioxidant and antibacterial activities from Elettariopsis curtisii Baker.

    Directory of Open Access Journals (Sweden)

    Vanida Chairgulprasert

    2008-08-01

    Full Text Available Elettariopsis curtisii Baker, the culinary and medicinal herb, was investigated to elucidate its chemical constituents and determine antioxidant and antibacterial activities. The essential oil of E. curtisii was obtained by steam distillation of fresh rhizomes in a maximum yield of 0.63%. GC-MS data indicated the presence of six compounds, of which trans-2-decenal (78.03% was the principal constituent. The essential oils and also the hexane, dichloromethane and methanol extracts from the rhizomes and leaves were assessed for antioxidant and antibacterial activities. In an evaluation of antioxidant activity, the crude dichloromethane extract of the leaves exhibited the highest scavenging effect on the DPPH radicalwith an EC50 of 0.28+0.01 mg/mL. The leaf dichloromethane extract also had the highest total phenol concentration, (73.4+2.80 mg GA/g of extract whereas the crude methanol extract from the rhizomes had the highest reducing power with an EC50 of 2.07+0.06 mg/mL. In terms of antibacterial activity, the essential oil (distilled from either the leaves or the rhizomesdisplayed the highest inhibitory activity, with the same MID value of 1 mg/disc against 5 strains of bacteria, Bacillus subtilis,Escherichia coli, Staphylococcus aureus, Sarcina sp. and Pseudomonas aeruginosa.

  4. Chemical profile of a polysaccharide from Psidium guajava leaves and it's in vivo antitussive activity.

    Science.gov (United States)

    Khawas, Sadhana; Sivová, Veronika; Anand, Namrata; Bera, Kaushik; Ray, Bimalendu; Nosáľová, Gabriela; Ray, Sayani

    2018-04-01

    Decoction of Psidium guajava leaves has been used as medication for chronic coughs and breathlessness for ages. Despite demonstration of antitussive activity, the specific molecule responsible for this remains unidentified. Herein, we report chemical profile and antitussive activity of its water extract (WE) and a polysaccharide (F1) present therein. This polysaccharide (F1), purified from WE by precipitation with ethanol and then through Cu(II)acetate, contains Ara, Gal, Rha, Glc and GalA residues, and has a molecular mass of 156 kDa. It comprises of terminal-, (1,5)- and (1,3,5)-linked Araf; (1,3)-, (1,6)- and (1,3,6)-linked Galp alongside (1,2)- and (1,2,4)-linked Rhap residues. Oligosaccharides indicating polysaccharide structure have been generated by Smith degradation and characterized. The WE fraction suppressed citric acid induced cough efforts in guinea pigs in the dose of 50 mg kg -1 . Assessment of antitussive activity of fractions prepared from WE namely F1 (polysaccharide) and F2 (ethanol soluble fraction) revealed that polysaccharide is the active component. Remarkably, tested samples do not alter the specific airway smooth muscle reactivity in animals significantly. The simple extraction method, prominent activity and favorable reactions profile suggest that this macromolecule could be an antitussive drug candidate. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Measurement of natural radioactivity in chemical fertilizer and agricultural soil: evidence of high alpha activity.

    Science.gov (United States)

    Ghosh, Dipak; Deb, Argha; Bera, Sukumar; Sengupta, Rosalima; Patra, Kanchan Kumar

    2008-02-01

    People are exposed to ionizing radiation from the radionuclides that are present in different types of natural sources, of which phosphate fertilizer is one of the most important sources. Radionuclides in phosphate fertilizer belonging to 232Th and 238U series as well as radioisotope of potassium (40K) are the major contributors of outdoor terrestrial natural radiation. The study of alpha activity in fertilizers, which is the first ever in West Bengal, has been performed in order to determine the effect of the use of phosphate fertilizers on human health. The data have been compared with the alpha activity of different types of chemical fertilizers. The measurement of alpha activity in surface soil samples collected from the cultivated land was also performed. The sampling sites were randomly selected in the cultivated land in the Midnapore district, which is the largest district in West Bengal. The phosphate fertilizer is widely used for large agricultural production, mainly potatoes. The alpha activities have been measured using solid-state nuclear track detectors (SSNTD), a very sensitive detector for alpha particles. The results show that alpha activity of those fertilizer and soil samples varies from 141 Bq/kg to 2,589 Bq/kg and from 109 Bq/kg to 660 Bq/kg, respectively. These results were used to estimate environmental radiation exposure on human health contributed by the direct application of fertilizers.

  6. Yellow-Cedar, Callitropsis (Chamaecyparis) nootkatensis, Secondary Metabolites, Biological Activities, and Chemical Ecology.

    Science.gov (United States)

    Karchesy, Joseph J; Kelsey, Rick G; González-Hernández, M P

    2018-05-01

    Yellow-cedar, Callitropsis nootkatensis, is prevalent in coastal forests of southeast Alaska, western Canada, and inland forests along the Cascades to northern California, USA. These trees have few microbial or animal pests, attributable in part to the distinct groups of biologically active secondary metabolites their tissues store for chemical defense. Here we summarize the new yellow-cedar compounds identified and their biological activities, plus new or expanded activities for tissues, extracts, essential oils and previously known compounds since the last review more than 40 years ago. Monoterpene hydrocarbons are the most abundant compounds in foliage, while heartwood contains substantial quantities of oxygenated monoterpenes and oxygenated sesquiterpenes, with one or more tropolones. Diterpenes occur in foliage and bark, whereas condensed tannins have been isolated from inner bark. Biological activities expressed by one or more compounds in these groups include fungicide, bactericide, sporicide, acaricide, insecticide, general cytotoxicity, antioxidant and human anticancer. The diversity of organisms impacted by whole tissues, essential oils, extracts, or individual compounds now encompasses ticks, fleas, termites, ants, mosquitoes, bacteria, a water mold, fungi and browsing animals. Nootkatone, is a heartwood component with sufficient activity against arthropods to warrant research focused toward potential development as a commercial repellent and biopesticide for ticks, mosquitoes and possibly other arthropods that vector human and animal pathogens.

  7. Chemical composition and antiprotozoal activities of Colombian Lippia spp essential oils and their major components

    Directory of Open Access Journals (Sweden)

    Patricia Escobar

    2010-03-01

    Full Text Available The chemical composition and biological activities of 19 essential oils and seven of their major components were tested against free and intracellular forms of Leishmania chagasi and Trypanosoma cruzi parasites as well as Vero and THP-1 mammalian cell lines. The essential oils were obtained from different species of Lippia, a widely distributed genus of Colombian plants. They were extracted by microwave radiation-assisted hydro-distillation and characterised by GC-FID and GC-MS. The major components were geranial, neral, limonene, nerol, carvacrol, p-cymene, γ-terpinene, carvone and thymol. The essential oil of Lippia alba exhibited the highest activity against T. cruzi epimastigotes and intracellular amastigotes with an IC50 of 5.5 μg/mL and 12.2 μg/mL, respectively. The essential oil of Lippia origanoides had an IC50 of 4.4 μg/mL in L. chagasi promastigotes and exhibited no toxicity in mammalian cells. Thymol (IC50 3.2 ± 0.4 μg/mL and S-carvone (IC50 6.1 ± 2.2 μg/mL, two of the major components of the active essential oils, were active on intracellular amastigotes of T. cruziinfected Vero cells, with a selective index greater than 10. None of the essential oils or major components tested in this study was active on amastigotes of L. chagasi infected THP-1 cells.

  8. Chemical composition and phagocyte immunomodulatory activity of Ferula iliensis essential oils.

    Science.gov (United States)

    Özek, Gulmira; Schepetkin, Igor A; Utegenova, Gulzhakhan A; Kirpotina, Liliya N; Andrei, Spencer R; Özek, Temel; Başer, Kemal Hüsnü Can; Abidkulova, Karime T; Kushnarenko, Svetlana V; Khlebnikov, Andrei I; Damron, Derek S; Quinn, Mark T

    2017-06-01

    Essential oil extracts from Ferula iliensis have been used traditionally in Kazakhstan for treatment of inflammation and other illnesses. Because little is known about the biologic activity of these essential oils that contributes to their therapeutic properties, we analyzed their chemical composition and evaluated their phagocyte immunomodulatory activity. The main components of the extracted essential oils were ( E )-propenyl sec -butyl disulfide (15.7-39.4%) and ( Z )-propenyl sec -butyl disulfide (23.4-45.0%). Ferula essential oils stimulated [Ca 2+ ] i mobilization in human neutrophils and activated ROS production in human neutrophils and murine bone marrow phagocytes. Activation of human neutrophil [Ca 2+ ] i flux by Ferula essential oils was dose-dependently inhibited by capsazepine, a TRPV1 channel antagonist, indicating that TRPV1 channels mediate this response. Furthermore, Ferula essential oils stimulated Ca 2+ influx in TRPV1 channel-transfected HEK293 cells and desensitized the capsaicin-induced response in these cells. Additional molecular modeling with known TRPV1 channel agonists suggested that the active component is likely to be ( Z )-propenyl sec -butyl disulfide. Our results provide a cellular and molecular basis to explain at least part of the beneficial therapeutic properties of FEOs. © Society for Leukocyte Biology.

  9. Chemical Composition and Antioxidant/Antimicrobial Activities in Supercritical Carbon Dioxide Fluid Extract of Gloiopeltis tenax

    Directory of Open Access Journals (Sweden)

    Jiaojiao Zheng

    2012-11-01

    Full Text Available Gloiopeltis tenax (G. tenax is widely distributed along the Chinese coastal areas and is commonly used in the treatment of diarrhea and colitis. This study aimed at investigating the bioactivities of the volatile constituents in G. tenax. We extracted the essential constituents of G. tenax by supercritical carbon dioxide extraction (CO2-SFE, then identified and analyzed the constituents by gas chromatography-mass spectrometry (GC-MS. In total, 30 components were identified in the G. tenax extract. The components showed remarkable antioxidant activity (radical scavenging activity of 2,2-diphenyl-1-picrylhydrazyl (DPPH, lipid peroxidation inhibition capacity (in a β-carotene/linoleic acid-coupled oxidation reaction, and hydroxyl radical-scavenging activity (by deoxyribose degradation by iron-dependent hydroxyl radical, compared to butylated hydroxytoluene. In microdilution assays, G. tenax extracts showed a moderate inhibitory effects on Staphyloccocus aureus (minimum inhibitory concentration (MIC = 3.9 mg/mL, Enterococcus faecalis (7.8 mg/mL, Pseudomonas aeruginosa (15.6 mg/mL, and Escherichia coli (3.9 mg/mL. Antioxidant and antimicrobial activities of G. tenax were related to the active chemical composition. These results suggest that the CO2-SFE extract from G. tenax has potential to be used as a natural antioxidant and antimicrobial agent in food processing.

  10. Characterization of mesoporous carbon prepared from date stems by H3PO4 chemical activation

    International Nuclear Information System (INIS)

    Hadoun, H.; Sadaoui, Z.; Souami, N.; Sahel, D.; Toumert, I.

    2013-01-01

    The present work was focused on the determination of texture, morphology, crystanillity and oxygenated surface groups characteristics of an activated carbon prepared from date stems. Chemical activation of this precursor at different temperatures (450, 550 and 650 °C) was adopted using phosphoric acid as dehydrating agent at (2/1) impregnation ratio. Fourier transform infrared spectroscopy study was carried out to identify surface groups in date stems activated carbons. The microscopic structure was examined by nitrogen adsorption at 77 K. The interlayer spacing (d 200 and d 100 ), stack height (L c ), stack width (L a ) and effective dimension L of the turbostratic crystallites (microcrystallite) in the date stems activated carbons were estimated from X-ray diffraction data (XRD). Results yielded a surface area, S BET , and total pore volume of 682, 1455, 1319 m 2 /g and 0,343, 1,045 and 0.735 cm 3 /g, for the carbon prepared at 450, 550 and 650 °C, respectively. Scanning electron microscopy exhibits a highly developed porosity which is in good agreement with the porous texture derived from gas adsorption data and these results confirm that the activated carbon is dominated by network of slit-shaped mesopores morphology and in some cases by varied micropores morphologies.

  11. Potassium carbonate mediated one-pot synthesis and antimicrobial activities of 2-alkoxy-4-(aryl-5H-indeno[1,2-b]pyridine-3-carbonitriles

    Directory of Open Access Journals (Sweden)

    Şahin Öztürk

    2016-12-01

    Full Text Available 2-Alkoxy-4-(aryl-5H-indeno[1,2-b]pyridine-3-carbonitriles (3a-e and 4a-e were synthesized via multicomponent reaction from 2-aryl-methylidineindan-1-ones (1a-e, malononitrile and K 2CO 3 in ethanol and/or methanol. The structures of obtained compounds (3a-e and 4a-e were characterized using the spectroscopic methods (NMR, IR and elemental analysis. Addition, the in vitro antimicrobial activities of compounds (3a-e were tested against the five human pathogenic bacteria. Penicillin G and Ceftriaxone antibiotics were used as positive control. The results were given as MIC values (minimum inhibition concentration, and compounds 3b-d showed very high activity against Escherichia coli 111.

  12. AMDE-1 is a dual function chemical for autophagy activation and inhibition.

    Directory of Open Access Journals (Sweden)

    Min Li

    Full Text Available Autophagy is the process by which cytosolic components and organelles are delivered to the lysosome for degradation. Autophagy plays important roles in cellular homeostasis and disease pathogenesis. Small chemical molecules that can modulate autophagy activity may have pharmacological value for treating diseases. Using a GFP-LC3-based high content screening assay we identified a novel chemical that is able to modulate autophagy at both initiation and degradation levels. This molecule, termed as Autophagy Modulator with Dual Effect-1 (AMDE-1, triggered autophagy in an Atg5-dependent manner, recruiting Atg16 to the pre-autophagosomal site and causing LC3 lipidation. AMDE-1 induced autophagy through the activation of AMPK, which inactivated mTORC1 and activated ULK1. AMDE-1did not affect MAP kinase, JNK or oxidative stress signaling for autophagy induction. Surprisingly, treatment with AMDE-1 resulted in impairment in autophagic flux and inhibition of long-lived protein degradation. This inhibition was correlated with a reduction in lysosomal degradation capacity but not with autophagosome-lysosome fusion. Further analysis indicated that AMDE-1 caused a reduction in lysosome acidity and lysosomal proteolytic activity, suggesting that it suppressed general lysosome function. AMDE-1 thus also impaired endocytosis-mediated EGF receptor degradation. The dual effects of AMDE-1 on autophagy induction and lysosomal degradation suggested that its net effect would likely lead to autophagic stress and lysosome dysfunction, and therefore cell death. Indeed, AMDE-1 triggered necroptosis and was preferentially cytotoxic to cancer cells. In conclusion, this study identified a new class of autophagy modulators with dual effects, which can be explored for potential uses in cancer therapy.

  13. Activation of chemical biological defense mechanisms and remission of vital oxidative injury by low dose radiation

    International Nuclear Information System (INIS)

    Yamaoka, K.; Nomura, T.; Kojima, S.

    2000-01-01

    Excessive active oxygen produced in vivo by various causes is toxic. Accumulation of oxidation injuries due to excessive active causes cell and tissue injuries, inducing various pathologic conditions such as aging and carcinogenesis. On the other hand, there are chemical defense mechanisms in the body that eliminate active oxygen or repair damaged molecules, defending against resultant injury. It is interesting reports that appropriate oxidation stress activate the chemical biological defense mechanisms. In this study, to elucidate these phenomena and its mechanism by low dose radiation, we studied on the below subjects. Activation of chemical biological defense mechanisms by low dose radiation: (1) The effects radiation on lipid peroxide (LPO) levels in the organs, membrane fluidity and the superoxide dismutase (SOD) activity were examined in rats and rabbits. Rats were irradiated with low dose X-ray over their entire bodies, and rabbits inhaled vaporized radon spring water, which primarily emitted α-ray. The following results were obtained. Unlike high dose X-ray, low dose X-ray and radon inhalation both reduced LPO levels and made the state of the SH-group on membrane-bound proteins closer to that of juvenile animals, although the sensitivity to radioactivity varied depending on the age of the animals and among different organs and tissues. The SOD activity was elevated, suggesting that low dose X-ray and radon both activate the host defensive function. Those changes were particularly marked in the organs related to immune functions of the animals which received low dose X-ray, while they were particularly marked in the brain after radon inhalation. It was also found that those changes continued for longer periods after low dose X-irradiation. (2) Since SOD is an enzyme that mediates the dismutation of O 2 - to H 2 O 2 , the question as to whether the resultant H 2 O 2 is further detoxicated into H 2 O and O 2 or not must still be evaluated. Hence, we studied

  14. Chemical Composition and Acetylcholinesterase Inhibitory Activity of Essential Oils from Piper Species.

    Science.gov (United States)

    Xiang, Cai-Peng; Han, Jia-Xin; Li, Xing-Cong; Li, Yun-Hui; Zhang, Yi; Chen, Lin; Qu, Yan; Hao, Chao-Yun; Li, Hai-Zhou; Yang, Chong-Ren; Zhao, San-Jun; Xu, Min

    2017-05-10

    The essential oils (EOs) derived from aromatic plants such as Piper species are considered to play a role in alleviating neuronal ailments that are associated with inhibition of acetylcholinesterase (AChE). The chemical compositions of 23 EOs prepared from 16 Piper spp. were analyzed by both gas chromatography with a flame ionization detector (GC-FID) and gas chromatography-mass spectrometry (GC-MS). A total of 76 compounds were identified in the EOs from the leaves and stems of 19 samples, while 30 compounds were detected in the EOs from the fruits of four samples. Sesquiterpenes and phenylpropanoids were found to be rich in these EOs, of which asaricin, caryophyllene, caryophyllene oxide, isospathulenol, (+)-spathulenol, and β-bisabolene are the major constituents. The EOs from the leaves and stems of Piper austrosinense, P. puberulum, P. flaviflorum, P. betle, and P. hispidimervium showed strong AChE inhibitory activity with IC 50 values in the range of 1.51 to 13.9 mg/mL. A thin-layer chromatography (TLC) bioautography assay was employed to identify active compound(s) in the most active EO from P. hispidimervium. The active compound was isolated and identified as asaricin, which gave an IC 50 value of 0.44 ± 0.02 mg/mL against AChE, comparable to galantamine with an IC 50 0.15 ± 0.01 mg/mL.

  15. Evaluation of Antioxidant Activities of Some Small Fruits Containing Anthocyanins Using Electrochemical and Chemical Methods

    Directory of Open Access Journals (Sweden)

    Adina Căta

    2016-06-01

    Full Text Available The objective of this work was to estimate the antioxidant capacity of some fruits extracts containing anthocyanins (strawberry, raspberry, elderberry, mulberry, blackberry, bilberry, black and red currant using an electrochemical technique and three classical chemical methods based on reaction between antioxidants and a chromogen compound. evaluation of antioxidant activities of extracts was performed by using FRAP (ferric reducing/antioxidant capacity, ABTS (2,2’-azinobis[3-ethylbenzothiazoline-6-sulphonate] and DPPH (2,2-diphenyl-1-picrylhydrazyl assays. Antioxidant activities of the extracts were correlated with their content of monomeric anthocyanins and total phenolics. Good correlations were obtained especially between antioxidant activities and total phenolics content. Cyclic voltammetry was used for the evaluation of overall reducing capacity of the extracts using a glassy carbon electrode. Reducing capacity of selected fruits extracts was assessed based on the half-peak potential (E1/2 of the first oxidation peak. The oxidation potentials characterized by E1/2 value were not correlated with the antioxidant activities evaluated by the classical methods. This work is licensed under a Creative Commons Attribution 4.0 International License.

  16. Chemical composition and antifungal activity of the essential oils of Lavandula pedunculata (Miller) Cav.

    Science.gov (United States)

    Zuzarte, Monica; Gonçalves, Maria J; Cavaleiro, Carlos; Dinis, Augusto M; Canhoto, Jorge M; Salgueiro, Lígia R

    2009-08-01

    The chemical composition and antifungal activity of the essential oils of Lavandula pedunculata (Miller) Cav., harvested in North and Central Portugal, were investigated. The essential oils were isolated by hydrodistillation and analyzed by GC and GC/MS. The minimal-inhibitory concentration (MIC) and the minimal-lethal concentration (MLC) of the essential oils and of their major constituents were used to evaluate the antifungal activity against different strains of fungi involved in candidosis, dematophytosis, and aspergillosis. The oils were characterized by a high percentage of oxygenated monoterpenes, the main compounds being 1,8-cineole (2.4-55.5%), fenchone (1.3-59.7%), and camphor (3.6-48.0%). Statistical analysis differentiated the essential oils into two main types, one characterized by the predominance of fenchone and the other one by the predominance of 1,8-cineole. Within the 1,8-cineole chemotype, two subgroups were well-defined taking into account the percentages of camphor. A significant antifungal activity of the oils was found against dermatophyte strains. The essential oil with the highest content of camphor was the most active with MIC and MLC values ranging from 0.32-0.64 microl/ml.

  17. Comparison of different methods for extraction from Tetraclinis articulata: yield, chemical composition and antioxidant activity.

    Science.gov (United States)

    Herzi, Nejia; Bouajila, Jalloul; Camy, Séverine; Romdhane, Mehrez; Condoret, Jean-Stéphane

    2013-12-15

    In the present study, three techniques of extraction: hydrodistillation (HD), solvent extraction (conventional 'Soxhlet' technique) and an innovative technique, i.e., the supercritical fluid extraction (SFE), were applied to ground Tetraclinis articulata leaves and compared for extraction duration, extraction yield, and chemical composition of the extracts as well as their antioxidant activities. The extracts were analyzed by GC-FID and GC-MS. The antioxidant activity was measured using two methods: ABTS(•+) and DPPH(•). The yield obtained using HD, SFE, hexane and ethanol Soxhlet extractions were found to be 0.6, 1.6, 40.4 and 21.2-27.4 g/kg respectively. An original result of this study is that the best antioxidant activity was obtained with an SFE extract (41 mg/L). The SFE method offers some noteworthy advantages over traditional alternatives, such as shorter extraction times, low environmental impact, and a clean, non-thermally-degraded final product. Also, a good correlation between the phenolic contents and the antioxidant activity was observed with extracts obtained by SFE at 9 MPa. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. Chemical composition, in vitro antitumor and pro-oxidant activities of Glandora rosmarinifolia (Boraginaceae) essential oil.

    Science.gov (United States)

    Poma, Paola; Labbozzetta, Manuela; Notarbartolo, Monica; Bruno, Maurizio; Maggio, Antonella; Rosselli, Sergio; Sajeva, Maurizio; Zito, Pietro

    2018-01-01

    The biological properties of essential oils have been demonstrated in the treatment of several diseases and to enhance the bioavailability of other drugs. In natural habitats the essential oils compounds may play important roles in the protection of the plants as antibacterials, antivirals, antifungals, insecticides and also against herbivores by reducing their appetite for such plants or by repelling undesirable others. We analyzed by gas-chromatography mass spectrometry the chemical composition of the essential oil of aerial parts of Glandora rosmarinifolia (Ten.) D.C. Thomas obtained by hydrodistillation and verified some biological activities on a panel of hepatocellular carcinoma cell lines (HA22T/VGH, HepG2, Hep3B) and triple negative breast cancer cell lines (SUM 149, MDA-MB-231). In the essential oil we detected 35 compounds. The results of the biological assays indicate that essential oil of G. rosmarinifolia induces cell growth inhibition at concentration-dependent way in all cell line models. This oil does not seem to possess antioxidant activity, while the cytotoxicity of G. rosmarinifolia essential oil appeared to involve, at least in part, a pro-oxidant mechanism. Our results show for the first time the antitumoral and pro-oxidant activities of G. rosmarinifolia essential oil and suggest that it may represent a resource of pharmacologically active compounds.

  19. Chemical Composition and Nematicidal Activity of Essential Oil of Agastache rugosa against Meloidogyne incognita

    Directory of Open Access Journals (Sweden)

    Zhi Wei Deng

    2013-04-01

    Full Text Available The aim of this research was to determine the chemical composition and nematicidal activity of essential oil of Agastache rugosa flowering aerial parts against the root knot nematode, Meloidogyne incognita, and to isolate and identify any nematicidal constituents from the essential oil. The essential oil of A. rugosa aerial parts was obtained by hydrodistillation and analyzed by GC-FID and GC-MS. A total of 37 components of the essential oil were identified, with the principal compounds being methyleugenol (50.51%, estragole (8.55%, and eugenol (7.54%, followed by thymol (3.62%, pulegone (2.56%, limonene (2.49% and caryophyllene (2.38%. Based on bioactivity-guided fractionation, the three active constituents were isolated from the essential oil and identified as methyleugenol, estragole and eugenol. The essential oil of A. rugosa exhibited strong nematicidal activity against M. incognita, with a LC50 value of 47.3 μg/mL. The components eugenol (LC50 = 66.6 μg/mL and methyleugenol (LC50 = 89.4 μg/mL exhibited stronger nematicidal activity against M. incognita (LC50 = 185.9 μg/mL. The results indicate that the essential oil of A. rugosa aerial parts and its constituent compounds have potential for development into natural nematicides for control of the root knot nematode.

  20. Biological Activities and Chemical Characterization of Cordia verbenacea DC. as Tool to Validate the Ethnobiological Usage

    Science.gov (United States)

    Matias, Edinardo Fagner Ferreira; Alves, Erivânia Ferreira; Santos, Beatriz Sousa; Sobral de Souza, Celestina Elba; de Alencar Ferreira, João Victor; Santos de Lavor, Anne Karyzia Lima; Figueredo, Fernando Gomes; Ferreira de Lima, Luciene; Vieira dos Santos, Francisco Antônio; Neves Peixoto, Flórido Sampaio; Viana Colares, Aracélio; Augusti Boligon, Aline; Saraiva, Rogério de Aquino; Athayde, Margareth Linde; da Rocha, João Batista Teixeira; Alencar Menezes, Irwin Rose; Douglas Melo Coutinho, Henrique; da Costa, José Galberto Martins

    2013-01-01

    Knowledge of medicinal plants is often the only therapeutic resource of many communities and ethnic groups. “Erva-baleeira”, Cordia verbenacea DC., is one of the species of plants currently exploited for the purpose of producing a phytotherapeutic product extracted from its leaves. In Brazil, its major distribution is in the region of the Atlantic Forest and similar vegetation. The crude extract is utilized in popular cultures in the form of hydroalcoholic, decoctions and infusions, mainly as antimicrobial, anti-inflammatory and analgesic agents. The aim of the present study was to establish a chemical and comparative profile of the experimental antibacterial activity and resistance modifying activity with ethnopharmacological reports. Phytochemical prospecting and HPLC analysis of the extract and fractions were in agreement with the literature with regard to the presence of secondary metabolites (tannins and flavonoids). The extract and fraction tested did not show clinically relevant antibacterial activity, but a synergistic effect was observed when combined with antibiotic, potentiating the antibacterial effect of aminoglycosides. We conclude that tests of antibacterial activity and modulating the resistance presented in this work results confirm the ethnobotanical and ethnopharmacological information, serving as a parameter in the search for new alternatives for the treatment of diseases. PMID:23818919

  1. Chemical composition and antibacterial activities of Illicium verum against antibiotic-resistant pathogens.

    Science.gov (United States)

    Yang, Jyh-Ferng; Yang, Cheng-Hong; Chang, Hsueh-Wei; Yang, Cheng-San; Wang, Shao-Ming; Hsieh, Ming-Che; Chuang, Li-Yeh

    2010-10-01

    In recent years, human pathogenic microorganisms have developed multiple drug resistance and caused serious nosocomial infections. In this study, we identified four new antimicrobial compounds from the Chinese herbal medicine Illicium verum and assessed their antibacterial efficacies. The supercritical CO₂ and ethanol extracts of Illicium verum showed substantial antibacterial activity against 67 clinical drug-resistant isolates, including 27 Acinetobacter baumannii, 20 Pseudomonas aeruginosa, and 20 methicillin-resistant Staphylococcus aureus. The diethyl ether (EE) fraction obtained from partition extraction and supercritical CO₂ extracts revealed an antibacterial activity with a minimum inhibitory concentration value of 0.15-0.70 mg/mL and 0.11 mg/mL, respectively. The EE fraction of I. verum showed synergetic effects with some commercial antibiotics. The antimicrobial mechanism was investigated with killing curves and scanning electron microscopy observation. The chemical components of the extracts were analyzed by spectrophotometry; (E)-anethole, anisyl acetone, anisyl alcohol, and anisyl aldehyde exhibited antibacterial activity against different clinical isolates. These extracts from I. verum can be further developed into antibiotic medicines due to their proven antibacterial activity.

  2. Antioxidant activity and chemical composition of Juniperus excelsa ssp. polycarpos wood extracts.

    Science.gov (United States)

    Hosseinihashemi, S K; Dadpour, A; Lashgari, A

    2017-03-01

    Extracts from the wood of Juniperus excelsa ssp. polycarpos were analysed for their antioxidant activity using the DPPH method and compared with ascorbic acid and butylated hydroxytoluene. The most active extracts were analysed for their chemical composition using gas chromatography-mass spectrometry. Acetone extract was found to be moderately active as an antioxidant agent at 58.38%, which was lower than the value of vitamin C (98.56%) at the concentration of 14.20 mg/mL. The major components identified in the acetone extract as trimethylsilyl (TMS) derivatives were pimaric acid TMS (24.56%), followed by α-d-glucopyranoside,1,3,4,6-tetrakis-O-(TMS)-β-d-fructofuranosyl 2,3,4,6-tetrakis-O-(TMS) (21.39%), triflouromethyl-bis-(TMS)methyl ketone (9.32%), and cedrol (0.72%). The dissolved water:methanol (1:1 v/v) partitioned from acetone extract afforded 12 fractions; among them, the F9 fraction was found to have good antioxidant activity (88.49%) at the concentration of 14.20 mg/mL. The major compounds identified in F9 fraction were α-d-glucopyranoside, 1,3,4,6-tetrakis-O-(TMS) (20.22%) and trifluoromethyl-bis-(TMS)methyl ketone (5.10%).

  3. Ethnobotany, chemical constituents and biological activities of the flowers of Hydnora abyssinica A.Br. (Hydnoraceae).

    Science.gov (United States)

    Al-Fatimi, M; Ali, N A A; Kilian, N; Franke, K; Arnold, N; Kuhnt, C; Schmidt, J; Lindequist, U

    2016-04-01

    Hydnora abyssinica A.Br. (Hydnoraceae), a holoparasitic herb, is for the first time recorded for Abyan governorate of South Yemen. Flowers of this species were studied for their ethnobotanical, biological and chemical properties for the first time. In South Yemen, they are traditionally used as wild food and to cure stomach diseases, gastric ulcer and cancer. Phytochemical analysis of the extracts showed the presence of terpenes, tannins, phenols, and flavonoids. The volatile components of the air-dried powdered flowers were identified using a static headspace GC/MS analysis as acetic acid, ethyl acetate, sabinene, α-terpinene, (+)-D-limonene and γ-terpinene. These volatile compounds that characterize the odor and taste of the flowers were detected for the first time in a species of the family Hydnoraceae. The flowers were extracted by n-hexane, dichlormethane, ethyl acetate, ethanol, methanol and water. With exception of the water extract all extracts demonstrated activities against Gram-positive bacteria as well as remarkable radical scavenging activities in DPPH assay. Ethyl acetate, methanol and water extracts exhibited good antifungal activities. The cytotoxic activity of the extracts against FL cells, measured in neutral red assay, was only weak (IC50 > 500 μg/mL). The results justify the traditional use of the flowers of Hydnora abyssinica in South Yemen.

  4. Biological Activities and Chemical Characterization of Cordia verbenacea DC. as Tool to Validate the Ethnobiological Usage.

    Science.gov (United States)

    Matias, Edinardo Fagner Ferreira; Alves, Erivânia Ferreira; Santos, Beatriz Sousa; Sobral de Souza, Celestina Elba; de Alencar Ferreira, João Victor; Santos de Lavor, Anne Karyzia Lima; Figueredo, Fernando Gomes; Ferreira de Lima, Luciene; Vieira Dos Santos, Francisco Antônio; Neves Peixoto, Flórido Sampaio; Viana Colares, Aracélio; Augusti Boligon, Aline; Saraiva, Rogério de Aquino; Athayde, Margareth Linde; da Rocha, João Batista Teixeira; Alencar Menezes, Irwin Rose; Douglas Melo Coutinho, Henrique; da Costa, José Galberto Martins

    2013-01-01

    Knowledge of medicinal plants is often the only therapeutic resource of many communities and ethnic groups. "Erva-baleeira", Cordia verbenacea DC., is one of the species of plants currently exploited for the purpose of producing a phytotherapeutic product extracted from its leaves. In Brazil, its major distribution is in the region of the Atlantic Forest and similar vegetation. The crude extract is utilized in popular cultures in the form of hydroalcoholic, decoctions and infusions, mainly as antimicrobial, anti-inflammatory and analgesic agents. The aim of the present study was to establish a chemical and comparative profile of the experimental antibacterial activity and resistance modifying activity with ethnopharmacological reports. Phytochemical prospecting and HPLC analysis of the extract and fractions were in agreement with the literature with regard to the presence of secondary metabolites (tannins and flavonoids). The extract and fraction tested did not show clinically relevant antibacterial activity, but a synergistic effect was observed when combined with antibiotic, potentiating the antibacterial effect of aminoglycosides. We conclude that tests of antibacterial activity and modulating the resistance presented in this work results confirm the ethnobotanical and ethnopharmacological information, serving as a parameter in the search for new alternatives for the treatment of diseases.

  5. Biological Activities and Chemical Characterization of Cordia verbenacea DC. as Tool to Validate the Ethnobiological Usage

    Directory of Open Access Journals (Sweden)

    Edinardo Fagner Ferreira Matias

    2013-01-01

    Full Text Available Knowledge of medicinal plants is often the only therapeutic resource of many communities and ethnic groups. “Erva-baleeira”, Cordia verbenacea DC., is one of the species of plants currently exploited for the purpose of producing a phytotherapeutic product extracted from its leaves. In Brazil, its major distribution is in the region of the Atlantic Forest and similar vegetation. The crude extract is utilized in popular cultures in the form of hydroalcoholic, decoctions and infusions, mainly as antimicrobial, antiinflammatory and analgesic agents. The aim of the present study was to establish a chemical and comparative profile of the experimental antibacterial activity and resistance modifying activity with ethnopharmacological reports. Phytochemical prospecting and HPLC analysis of the extract and fractions were in agreement with the literature with regard to the presence of secondary metabolites (tannins and flavonoids. The extract and fraction tested did not show clinically relevant antibacterial activity, but a synergistic effect was observed when combined with antibiotic, potentiating the antibacterial effect of aminoglycosides. We conclude that tests of antibacterial activity and modulating the resistance presented in this work results confirm the ethnobotanical and ethnopharmacological information, serving as a parameter in the search for new alternatives for the treatment of diseases.

  6. A Study on an Executive Technique and Activation of Clean Production in Chemical Industry

    Energy Technology Data Exchange (ETDEWEB)

    Kong, Seong Yong; Lee, Hee Seok; Kim, Kang Seok [Korea Environment Institute, Seoul (Korea)

    2000-12-01

    Clean production does not only make the sustainable development possible through preventing the deterioration of the environmental pollution from the expansion of industrialization but also enhance the company's competitiveness. Clean production is required by all industrial fields but is the most important in chemical industry. The Government has made efforts to change the domestic industrial structure to the environmental-friendly structure through developing the research. However, the domestic industry has not yet activated overall except some large companies, which has concretized the activation of clean production. Especially, the medium and small companies are more sluggish due to the inferiority of capital and technology. With recognizing that the main body of clean production is a company, the effort based on the Government and the academic world, without companies' positive, will cannot help being limited in effects. Therefore, it is necessary to trigger the schemes that urge the companies' motivation to show the effects from the support that have concentrated in hardware like technology until now. It seems to be very important that the guidebook for clean production, which a company can easily adopt, is developed and spread. This report provides the guidebook for clean production that managers and engineers can easily understand and approach in a producing field and presents the scheme to promote clean production, for chemical industry that is seriously required clean production. Even if the presented contents are not perfect, they can be applied to the development of the Government's policy and the administrative activities of companies for clean production as a useful data. 53 refs., 5 figs., 30 tabs.

  7. Antimicrobial activity and chemical composition of the essential oils of Portuguese Foeniculum vulgare fruits.

    Science.gov (United States)

    Mota, Ana S; Martins, M Rosário; Arantes, Sílvia; Lopes, Violeta R; Bettencourt, Eliseu; Pombal, Sofia; Gomes, Arlindo C; Silva, Lúcia A

    2015-04-01

    The aim of this study was to investigate the chemical composition and antimicrobial activity of essential oils obtained by hydrodistillation from fruits of six fennel accessions collected from wild populations occurring in the centre and south of Portugal. Composition of essential oils was established by Gas Chromatography-Flame Ionization Detector (GC-FID) and Gas Chromatography-Mass Spectrometry (GC-MS) analysis. The obtained yields of the essential oils were found to vary greatly in the range of 1.1 to 2.9% (v/w) and the chemical composition varied with the region of collection. A total of 16 compounds were identified. The main compounds were fenchone (16.9 - 34.7%), estragole (2.5 - 66.0%) and trans-anethole (7.9 - 77.7%). The percentages of these three main compounds were used to determine the relationship between the different oil samples and to group them into four different chemotypes: anethole/fenchone; anethole; estragole and anethole/estragole. Antifungal activity of essential oils was evaluated against six food spoilage fungi: Aspergillus niger, A. japonicus, A. oryzae, Fusarium oxysporum, Rhizophus oryzae and R. stolonifer. Antibacterial activity was assessed against three Gram-positive strains: Enterococcus faecalis ATCC 29212, Staphylococcus epidermidis ATCC 12228 and S. aureus ATCC 28213; and against six Gram-negative strains: Escherichia coli ATCC 25922; Morganella morganii LFG 08; Proteus mirabilis LFG 04; Salmonella enteritidis LFG 05; S. entiritidis serovar typhimurium LFG 06 and Pseudomonas aeruginosa ATCC 27853 by the disc diffusion agar method; the minimal inhibitory concentration (MIC) was determined using the broth macro-dilution method. The MIC values varied from 62.5 (E. coli ATCC 25922) to 2000 µmL (P. aeruginosa ATCC 27853).

  8. Preparation of carbon dioxide adsorbents from the chemical activation of urea-formaldehyde and melamine-formaldehyde resins

    Energy Technology Data Exchange (ETDEWEB)

    T.C. Drage; A. Arenillas; K.M. Smith; C. Pevida; S. Piippo; C.E. Snape [University of Nottingham, Nottingham (United Kingdom). Nottingham Fuel and Energy Centre, School of Chemical, Environmental and Mining Engineering

    2007-01-15

    Adsorption is considered to be one of the more promising technologies for the capture of CO{sub 2} from flue gases. In general, nitrogen enrichment is reported to be effective in enhancing the specific adsorbent-adsorbate interaction for CO{sub 2}. Nitrogen enriched carbons were produced from urea-formaldehyde and melamine-formaldehyde resins polymerised in the presence of K{sub 2}CO{sub 3} as a chemical activation agent, with activation undertaken over a range of temperatures. CO{sub 2} adsorption capacity was determined to be dependent upon both textural properties and more importantly nitrogen functionality. Adsorbents capable of capturing above 8 wt.% CO{sub 2} at 25{sup o}C were produced from the chemical activation of urea-formaldehyde resin at 500{sup o}C. Chemical activation seems to produce more effective adsorbents than CO{sub 2} activation. 29 refs., 4 figs., 3 tabs.

  9. Agrice 1994-2000 - Activity report. Agriculture for chemicals and energy

    International Nuclear Information System (INIS)

    2001-01-01

    The emergence of new energy, chemicals and materials markets for agricultural products calls for an ongoing commitment to significant and stable funding for research. Even more importantly, these new markets also necessitate better coordination between the actors across the field, ranging from multidisciplinary research teams and agro-industrial companies to users in the petrochemicals, chemicals and materials sectors, and agricultural production. The need for this coordination is even greater today, in light of the key role that 'non-food' supply chains play in environmental protection: efforts to mitigate the greenhouse effect, reduction of VOC emissions, product safety and biodegradability, rational farming practices, etc. With these ends in mind the scientific interest group AGRICE- Agriculture for Chemicals and Energy- was created in France in 1994 by government bodies and eight partners. Today AGRICE includes the following members: the Institut Francais du Petrole (IFP), the Institut National de Recherche Agronomique (INRA), the Centre National de Recherche Scientifique (CNRS) and the Agence de l'Environnement et de la Maitrise de l'Energie (ADEME), professional organisations in oilseeds (ONIDOL), grains (AGPB) and beets (CGB), AVENTIS, TOTAL FINA ELF, LIMAGRAIN and EDF, the French ministries of Agriculture, Industry, Research, and Environment. AGRICE was founded for a six-year renewable term, and its management entrusted to ADEME. The group has worked to develop significant collaborative efforts across Europe, notably through the European Renewable Resources and Materials Association (ERRMA). AGRICE is due to be renewed with a broader base of partners in 2001. This report presents: 1 - the AGRICE profile, scope of activity (Biofuels vehicles (Ester/Oils, Ethanol/Ether) and non-vehicles (Energy crops, Processes), Biomolecules (Lubricants, Surfactants, Solvents, Other biomolecules), Biomaterials (Biopolymers, Agro-materials)), Financial report 1994

  10. Disposal of chemical agents and munitions stored at Umatilla Depot Activity, Hermiston, Oregon

    Energy Technology Data Exchange (ETDEWEB)

    Zimmerman, G.P.; Hillsman, E.L.; Johnson, R.O.; Miller, R.L.; Patton, T.G.; Schoepfle, G.M.; Tolbert, V.R.; Feldman, D.L.; Hunsaker, D.B. Jr.; Kroodsma, R.L.; Morrissey, J.; Rickert, L.W.; Staub, W.P.; West, D.C.

    1993-02-01

    The Umatilla Depot Activity (UMDA) near Hermiston, Oregon, is one of eight US Army installations in the continental United States where lethal unitary chemical agents and munitions are stored, and where destruction of agents and munitions is proposed under the Chemical Stockpile Disposal Program (CSDP). The chemical agent inventory at UMDA consists of 11.6%, by weight, of the total US stockpile. The destruction of the stockpile is necessary to eliminate the risk to the public from continued storage and to dispose of obsolete and leaking munitions. In 1988 the US Army issued a Final Programmatic Environmental Impact Statement (FPEIS) for the CSDP that identified on-site disposal of agents and munitions as the environmentally preferred alternative (i.e., the alternative with the least potential to cause significant adverse impacts), using a method based on five measures of risk for potential human health and ecosystem/environmental effects; the effectiveness and adequacy of emergency preparedness capabilities also played a key role in the FPEIS selection methodology. In some instances, the FPEIS included generic data and assumptions that were developed to allow a consistent comparison of potential impacts among programmatic alternatives and did not include detailed conditions at each of the eight installations. The purpose of this Phase 1 report is to examine the proposed implementation of on-site disposal at UMDA in light of more recent and more detailed data than those included in the FPEIS. Specifically, this Phase 1 report is intended to either confirm or reject the validity of on-site disposal for the UMDA stockpile. Using the same computation methods as in the FPEIS, new population data were used to compute potential fatalities from hypothetical disposal accidents. Results indicate that onsite disposal is clearly preferable to either continued storage at UMDA or transportation of the UMDA stockpile to another depot for disposal.

  11. Chemical composition, antioxidative and antimicrobial activity of essential oil Ocimum sanctum L.

    Directory of Open Access Journals (Sweden)

    Beatović Damir V.

    2013-01-01

    Full Text Available Ocimum sanctum L. (Lamiaceae sin. Ocimum tenuiflorum L. or Tulsi basil is a plant originating from tropical and subtropical areas of India. It is used in both the traditional and official medicine in India. Tulsi is a type of basil that is insufficiently explored and studied in Europe. The goal of this paper is to determine the chemical composition, antioxidative, and antimicrobial activity of the essential oil Ocimum sanctum L. grown in Serbia. The quantity of essential oil in 100 g of herb (v/w is 0.68%, with 41 components identified in the tested essential oil. The most represented chemical group are sesquiturpene hydrocarbonates with 80.47%. Other groups were much less represented. Sesquiturpene hydrocarbonate β-cariophyllene is a predominant component in the essential oil with 63.80%. The quantity of tested essential oil needed to achieve 50% of inhibition of DPPH radicals is 0.35 μg/ml, and it has high potential to neutralize free radicals. The essential oil exhibited antibacterial activity to all tested strains of bacteria, both Gram-positive and Gram-negative. It affected all strains in an inhibitory way in the interval 0.34-41.50 μl/ml, and in a bactericide way within the range 22.50-124.5 μl/ml. The most sensitive strains of bacteria are Salmonella typhimurium and Escherichia coli, while Listeria monocytogenes and Enterococus faecalis showed greatest resistance. The essential oil exhibited antifugal activity on all tested fungi. It affected all tested fungi in an inhibitory way in the interval 4.42-8.83 μl/ml, and in a microbicide way within the range 10.00-50.00 μl/ml. The most sensitive fungi are: Aspergillus ochraceus, Penicillium ochrochloron and Penicilium funiculosum, while the most resistent one is Aspergillus niger. The tested basil essential oil Ocimum sanctum demonstrated significant antioxidative and antimicrobial effect and may be used as a raw material in food, pharmaceutical and chemical industries.

  12. Chemical Analysis and Biological Activity of the Essential Oils of Two Endemic Soqotri Commiphora Species

    Directory of Open Access Journals (Sweden)

    Wulf Schultze

    2010-02-01

    Full Text Available The barks of two endemic Commiphora species namely, Commiphora ornifolia (Balf.f. Gillett and Commiphora parvifolia Engl., were collected from Soqotra Island in Yemen and their essential oils were obtained by hydrodistillation. The chemical composition of both oils was investigated by GC and GC-MS. Moreover, the essential oils were evaluated for their antimicrobial activity against two Gram-positive bacteria, two Gram-negative bacteria and one yeast species by using a broth micro-dilution assay for minimum inhibitory concentrations (MIC and for their antioxidant activity by measuring the DPPH radical scavenging activity. A total of 45 constituents of C. ornifolia (85.6% and 44 constituents of C. parvifolia (87.1% were identified. The oil of C. ornifolia was characterized by a high content of oxygenated monoterpenes (56.3%, of which camphor (27.3%, α-fenchol (15.5%, fenchone (4.4% and borneol (2.9% were identified as the main components. High contents of oxygenated sesquiterpenes (36.1% and aliphatic acids (22.8% were found in C. parvifolia oil, in which caryophyllene oxide (14.2%, β-eudesmol (7.7%, bulnesol (5.7%, T-cadinol (3.7% and hexadecanoic acid (18.4% predominated. The results of the antimicrobial assay showed that both oils exhibited moderate to high antibacterial activity especially against Gram-positive bacteria. C. ornifolia oil was the most active. In addition, the DPPH-radical scavenging assay exhibited only weak antioxidant activities for both oils at the high concentration tested.

  13. Endocrine-disrupting activity of hydraulic fracturing chemicals and adverse health outcomes after prenatal exposure in male mice

    Science.gov (United States)

    Kassotis, Christopher D.; Klemp, Kara C.; Vu, Danh C.; Lin, Chung-Ho; Meng, Chun-Xia; Besch-Williford, Cynthia L.; Pinatti, Lisa; Zoeller, R. Thomas; Drobnis, Erma Z.; Balise, Victoria D.; Isiguzo, Chiamaka J.; Williams, Michelle A.; Tillitt, Donald E.; Nagel, Susan C.

    2015-01-01

    Oil and natural gas operations have been shown to contaminate surface and ground water with endocrine-disrupting chemicals. In the current study, we fill several gaps in our understanding of the potential environmental impacts related to this process. We measured the endocrine-disrupting activities of 24 chemicals used and/or produced by oil and gas operations for five nuclear receptors using a reporter gene assay in human endometrial cancer cells. We also quantified the concentration of 16 of these chemicals in oil and gas wastewater samples. Finally, we assessed reproductive and developmental outcomes in male C57BL/6J mice after the prenatal exposure to a mixture of these chemicals. We found that 23 commonly used oil and natural gas operation chemicals can activate or inhibit the estrogen, androgen, glucocorticoid, progesterone, and/or thyroid receptors, and mixtures of these chemicals can behave synergistically, additively, or antagonistically in vitro. Prenatal exposure to a mixture of 23 oil and gas operation chemicals at 3, 30, and 300 μg/kg · d caused decreased sperm counts and increased testes, body, heart, and thymus weights and increased serum testosterone in male mice, suggesting multiple organ system impacts. Our results suggest possible adverse developmental and reproductive health outcomes in humans and animals exposed to potential environmentally relevant levels of oil and gas operation chemicals.

  14. Synthesis of CuS nanoparticles by a wet chemical route and their photocatalytic activity

    Energy Technology Data Exchange (ETDEWEB)

    Pal, Mou; Mathews, N. R. [Universidad Nacional Autónoma de México, Instituto de Energías Renovables (Mexico); Sanchez-Mora, E.; Pal, U. [Instituto de Física, BUAP (Mexico); Paraguay-Delgado, F. [Centro de Investigación en Materiales Avanzados (CIMAV), Departamento de Materiales Nanoestructurados (Mexico); Mathew, X., E-mail: xm@ier.unam.mx [Universidad Nacional Autónoma de México, Instituto de Energías Renovables (Mexico)

    2015-07-15

    CuS nanoparticles (NPs) of few nanometers in size were prepared by a wet chemical method. The structural, compositional, and optical properties of the NPs were characterized by X-ray diffraction (XRD), scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, micro Raman and Fourier transform infrared spectroscopy, N{sub 2} adsorption–desorption isotherms, and UV–Vis diffuse reflectance spectroscopy. The XRD pattern proved the presence of hexagonal phase of CuS particles which was further supported by Raman spectrum. The estimated band gap energy of 2.05 eV for the slightly sulfur-rich CuS NPs is relatively larger than that of bulk CuS (1.85 eV), indicating the small size effect. As-prepared NPs showed excellent photocatalytic activity for the degradation of methylene blue (MB) under visible light. The surface-bound OH{sup −} ions at the CuS nanostructures help adsorb MB molecules facilitating their degradation process under visible light illumination. The studies presented in this paper suggest that the synthesized CuS NPs are promising, efficient, stable, and visible-light-sensitive photocatalyst for the remediation of wastewater polluted by chemically stable azo dyes such as MB.

  15. Effects of pesticide chemicals on the activity of metabolic enzymes: focus on thiocarbamates.

    Science.gov (United States)

    Mathieu, Cécile; Duval, Romain; Xu, Ximing; Rodrigues-Lima, Fernando; Dupret, Jean-Marie

    2015-01-01

    Thiocarbamates are chemicals widely used as pesticides. Occupational exposure is associated with acute intoxication. Populations can be exposed through food and water. Moreover, certain thiocarbamates are used clinically. The widespread use of thiocarbamates raises many issues regarding their toxicological and pharmacological impact. Thiocarbamates and their metabolites can modify biological macromolecules functions, in particular enzymes, through modification of cysteine residues, chelation of metal ions or modulation of the oxidative stress. Loss of enzyme activity can lead to the disruption of metabolic pathways, and explain, at least in part, the effects of these pesticides. Additionally, their reactivity and ability to easily cross biological barrier confer them a great interest for development of clinical applications. Many advances in the study of thiocarbamates metabolism and reactivity have led to a better knowledge of biological effects of these compounds. However, more data are needed on the determination of targets and specificity. Only few data concerning the exposure to a cocktail of pesticides/chemicals are available, raising the need to evaluate the toxic side effects of representative pesticides mixtures. Moreover, the dithiocarbamate Disulfiram has shown great potential in therapeutic applications and leads to the development of pharmacological thiocarbamates derivatives, highly specific to their target and easily distributed.

  16. Chemical analysis and antihyperglycemic activity of an original extract from burdock root (Arctium lappa).

    Science.gov (United States)

    Tousch, Didier; Bidel, Luc P R; Cazals, Guillaume; Ferrare, Karine; Leroy, Jeremy; Faucanié, Marie; Chevassus, Hugues; Tournier, Michel; Lajoix, Anne-Dominique; Azay-Milhau, Jacqueline

    2014-08-06

    In the present study, we obtained a dried burdock root extract (DBRE) rich in caffeoylquinic acids derivatives. We performed the chemical characterization of DBRE and explored its antihyperglycemic potential in both in vitro and in vivo experiments. Chemical analysis of DBRE using LC-MS and GC-MS revealed the presence of a great majority of dicaffeoylquinic acid derivatives (75.4%) of which 1,5-di-O-caffeoyl-4-O-maloylquinic acid represents 44% of the extract. In the in vitro experiments, DBRE is able to increase glucose uptake in cultured L6 myocytes and to decrease glucagon-induced glucose output from rat isolated hepatocytes together with a reduction of hepatic glucose 6-phosphatase activity. DBRE did not increase insulin secretion in the INS-1 pancreatic β-cell line. In vivo, DBRE improves glucose tolerance both after intraperitoneal and oral subchronic administration. In conclusion, our data demonstrate that DBRE constitutes an original set of caffeoylquinic acid derivatives displaying antihyperglycemic properties.

  17. Can phylogeny predict chemical diversity and potential medicinal activity of plants? A case study of amaryllidaceae

    Directory of Open Access Journals (Sweden)

    Rønsted Nina

    2012-09-01

    Full Text Available Abstract Background During evolution, plants and other organisms have developed a diversity of chemical defences, leading to the evolution of various groups of specialized metabolites selected for their endogenous biological function. A correlation between phylogeny and biosynthetic pathways could offer a predictive approach enabling more efficient selection of plants for the development of traditional medicine and lead discovery. However, this relationship has rarely been rigorously tested and the potential predictive power is consequently unknown. Results We produced a phylogenetic hypothesis for the medicinally important plant subfamily Amaryllidoideae (Amaryllidaceae based on parsimony and Bayesian analysis of nuclear, plastid, and mitochondrial DNA sequences of over 100 species. We tested if alkaloid diversity and activity in bioassays related to the central nervous system are significantly correlated with phylogeny and found evidence for a significant phylogenetic signal in these traits, although the effect is not strong. Conclusions Several genera are non-monophyletic emphasizing the importance of using phylogeny for interpretation of character distribution. Alkaloid diversity and in vitro inhibition of acetylcholinesterase (AChE and binding to the serotonin reuptake transporter (SERT are significantly correlated with phylogeny. This has implications for the use of phylogenies to interpret chemical evolution and biosynthetic pathways, to select candidate taxa for lead discovery, and to make recommendations for policies regarding traditional use and conservation priorities.

  18. [Chemical constituents from petroleum ether fraction of Swertia chirayita and their activities in vitro].

    Science.gov (United States)

    You, Rong-Rong; Chen, Xue-Qing; He, Dan-Dan; Huang, Chang-Gao; Jin, Yang; Qian, Shi-Hui; Ju, Jian-Ming; Fan, Jun-Ting

    2017-10-01

    The present work is to study the chemical constituents from petroleum ether fraction of Tibetan medicine Swertia chirayita by column chromatography and recrystallization. The structures were identified by physical and chemical properties and spectral data as swerchirin (1), decussatin (2), 1,8-dihydroxy-3,5,7-trimethoxyxanthone (3), 1-hydroxy-3,5,7,8-tetramethoxyxanthone (4), bellidifolin (5), 1-hydroxy-3, 7-dimethoxyxanthone (6), methylswertianin (7), 1-hydroxy-3,5-dimethoxyxanthone (8), erythrodiol (9), oleanolic acid (10), gnetiolactone (11), scopoletin (12), sinapaldehyde (13), syringaldehyde (14), and β-sitosterol (15). Compounds 3, 4, 9, 11-14 were isolated from S. chirayita for the first time. Compounds 9 and 12 were firstly isolated from the genus Swertia. The cytotoxic activities of compounds 1, 2, 5, 7 and 8 against human pancreatic cancer cell lines SW1990 and BxPC-3,and the protective effects of these compounds against hydrogen peroxide (H2O2)-induced oxidative stress in human endothelium-derived EA.hy926 were investigated in vitro. The results showed no obvious effect at the high concentration of 50 μmol•L⁻¹. Copyright© by the Chinese Pharmaceutical Association.

  19. Chemical characterization of diets consumed in the COSEAS restaurant, by neutron activation analysis

    International Nuclear Information System (INIS)

    Favaro, Deborah I.T.; Chioccola, Gabriella S.; Bortoli, Maritsa C.; Cozzolino, Silvia M.F.

    2005-01-01

    This study presents the results of chemical characterization of meals (lunch) offered by COSEAS/USP-SP restaurant, during 5 non consecutive days. These meals were collected in triplicate, in the same way they are offered to the users, being freeze-dried and prepared for chemical analysis. In the total, 15 samples were collected. The proximate composition was determined by using the standard methodologies according to AOAC (1995). The contents of some micronutrients (Ca, Fe, K, Na, Se and Zn) were determined by instrumental neutron activation analysis. The methodology validation was performed by certified reference materials analyses: Oyster Tissue (NIST SRM 1566 b ), Orchard Leaves (NIST SRM 1541) and Peach Leaves (NIST SRM 1547). >From concentration results the daily intake of each micronutrient was calculated considering this meal as 40% of the total daily intake and the values were compared to the new dietary recommendations of micronutrients (Dietary Reference Intakes-DRIs, Institute of Medicine, USA), for the women in the life stage from 19 to 30 years. Comparing the average values found with the recommended values, it was verified that macronutrients and Fe, Se and Zn micronutrients reached the values set by new DRIs. For Ca and K the daily intake was inadequate and Na, exceeded the recommended value. (author)

  20. Bufadienolides of Kalanchoe species: an overview of chemical structure, biological activity and prospects for pharmacological use.

    Science.gov (United States)

    Kolodziejczyk-Czepas, Joanna; Stochmal, Anna

    2017-01-01

    Toad venom is regarded as the main source of bufadienolides; however, synthesis of these substances takes also place in a variety of other animal and plant organisms, including ethnomedicinal plants of the Kalanchoe genus. Chemically, bufadienolides are a group of polyhydroxy C-24 steroids and their glycosides, containing a six-membered lactone (α-pyrone) ring at the C-17β position. From the pharmacological point of view, bufadienolides might be a promising group of steroid hormones with cardioactive properties and anticancer activity. Most of the literature concerns bufadienolides of animal origin; however, the medicinal use of these compounds remains limited by their narrow therapeutic index and the risk of development of cardiotoxic effects. On the other hand, plants such as Kalanchoe are also a source of bufadienolides. Kalanchoe pinnata (life plant, air plant, cathedral bells), Kalanchoe daigremontiana (mother of thousands) and other Kalanchoe species are valuable herbs in traditional medicine of Asia and Africa. The present review focuses on the available data on chemical structures of 31 compounds, biological properties and prospects for therapeutic use of bufadienolides from Kalanchoe species. Furthermore, it presents some new investigational trends in research on curative uses of these substances.

  1. Chemical stress induced by heliotrope (Heliotropium europaeum L.) allelochemicals and increased activity of antioxidant enzymes.

    Science.gov (United States)

    Abdulghader, Kalantar; Nojavan, Majid; Naghshbandi, Nabat

    2008-03-15

    The aims of this study were to evaluate the allelopathic potential of heliotrope on some biochemical processes of dodder. The preliminary experiments revealed that the effect of aqueous extract of leaves of heliotrope is higher than its seeds and roots. So, the aqueous extract of leaves was used in remaining experiments. Leaf extracts of 5 g powder per 100 mL H2O inhibited the germination of dodder seeds up to 95% and that of radish up to 100%. While, the aqueous extract of vine leaves which is a non-allelopathic plant did not have any inhibitory effect on these seeds. Vine leaf was used as a control to show that the inhibitory effect of heliotrope is due to an inhibitory compound but not due to the concentration. The leaf extract of heliotrope at 0.0, 0.1, 1.0, 2, 3, 4 and 5 g powder per 100 mL H2O reduced the radish seedling growth from 14 cm to about 0.5 cm and that of dodder from 7.5 cm to about 0.25 cm. The effects of heliotrope allelochemicals on some physiological and biochemical processes of radish was also Investigated. The activity of auxin oxidase increased in leaves and roots of radish. Suggesting that the reduced radish growth is due to the decreased active auxin levels in its leaves and roots. The activity of alpha-amylase was reduced, so reduction of starch degradation and lack of respiratory energy is the prime reason of germination inhibition in dodder and radish seeds. The level of soluble sugars increased. This is an indication of reduction of the activity of some respiratory enzymes and reduced consumption of these sugars. Proline levels were also increased, indicating that, the chemical stress is induced by leaf extract. Finally, the activities of GPX and CAT which are antioxidant enzymes were increased, along with increased extract concentration. These finding shows that the chemical stress induced by leaf extract produces super oxide (O2*) and H2O2, which is neutralized to H2O and O2 by these enzymes.

  2. Chemical Composition of a New Taxon, Seseli gummiferum subsp. ilgazense, and its Larvicidal Activity against Aedesaegypti

    Directory of Open Access Journals (Sweden)

    Mine Kurkcuoglu

    2018-03-01

    Full Text Available Mosquitoes are vectors for many pathogens and parasites that cause human diseases including dengue, yellow fever, West Nile, chikungunya, filariasis and malaria which cause high rates of human morbidity and mortality under extreme conditions. Plants are an excellent source for mosquito control agents because they constitute rich sources of bioactive chemicals. They are also biodegradable and environment-friendly. The present study reports on the larvicidal activity of the essential oil of Seseli gummiferum. subsp. ilgazense (Apiaceae against Aedes aegypti larvae. Essential oil showed 100 and 70% mortality at 125 and 62.6 ppm, respectively, with no mortality at 31.25 ppm. Aerial parts of S. gummiferum subsp. ilgazense were subjected to hydrodistillation to yield 0.6% oil. The essential oil was analyzed by GC-FID and GC-MS techniques. The main constituents in the oil were sabinene (28.8%, germacrene D (9.5% and α -pinene (7.2%.

  3. Physico-chemical characterization studies of activated carbon derived from Sterculia Quadrifida seed shell waste

    Directory of Open Access Journals (Sweden)

    P. Shanthi

    2014-09-01

    Full Text Available A carbonaceous adsorbent prepared from the Sterculia Quadrifida shell by various activation process, viz., Acid process, Chloride process, Carbonate process and Sulphate process are successfully reported. It shows excellent improvement in the surface characteristics. Their physico-chemical characterization studies such as bulk density, moisture content, ash content, fixed carbon content, matter, soluble in water, matter soluble in acid, pH, decolourizing power, porosity and specific gravity have been carried out to assess the suitability of these carbons as potential adsorbent for waste water treatment. The present study undertaken to evaluate the efficiency of a carbon adsorbent prepared from Sterculia Quadrifida seed shell waste for removal of dyes in aqueous solution.

  4. The geographical origin and chemical composition in phellinus mushrooms measured by instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    Lim, J.M.; Sun, G.M.; Moon, J.H.; Chung, Y.S.; Lee, J.H.; Kim, K.H.

    2012-01-01

    In order to expand the utilization of phellinus mushrooms as a dietary supplement, we attempted to evaluate the chemical composition by measuring its inorganic elemental content with the aid of instrumental neutron activation analysis (INAA). Twenty seven phellinus mushrooms samples were collected from Korea, Cambodia, and Vietnam. A total of 28 elements were analyzed in the phellinus mushroom samples using the INAA. The concentrations of Ca, K, and Mg are much higher than those of other elements in phellinus mushroom samples. The sum of determined elemental concentration in Cambodia samples was about 2-6 times higher than those in Korea and Vietnam samples, respectively. Based on our measurement data, we attempted to discriminate the geographical origin using principal components analysis (PCA) and linear discriminant analysis (LDA). The geographical origins of all samples were clearly classified with correct classification rate of 100%. (author)

  5. Chemical composition and antioxidant activities of some indigenous spices consumed in Nigeria.

    Science.gov (United States)

    Ene-Obong, Henrietta; Onuoha, NneOla; Aburime, Lilian; Mbah, Obioma

    2018-01-01

    The chemical compositions and antioxidant capacities of seven spices consumed in Southern Nigeria were determined. They were purchased from majors markets in the study area. Edible portions of the spices were ground into fine powder and their nutrient and phytochemical compositions determined using standard methods. Antioxidant activity were determined on aqueous extract using standard assays, namely, 1,1-diphenyl-2picrylhydrazyl (DPPH) free radical ability and ferric reducing antioxidant potential (FRAP). The spices were rich in macro-and micro-nutrients. Ricinodendron heudelotii had the highest protein (30.6%) and fat (24.6%) contents. Tetrapleura tetraptera had the least fat content. The total phenol, flavonoid and vitamin C contents differed significantly (pspices have good nutrient profile and antioxidant potentials. Their increased consumption is recommended and use as functional foods needs to be exploited. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Partial chemical composition and antimicrobial activity of Daucus crinitus Desf. extracts

    Energy Technology Data Exchange (ETDEWEB)

    Dib, M. A.; Bendahou, M.; Bendiabdellah, A.; Djabou, N.; Allali, H.; Tabti, B.; Paolini, J.; Costa, J.

    2010-07-01

    The chemical composition of fatty acids and the unsaponifiable fraction of the roots, leaves and stems from Daucus crinitus Desf. were, determined using gas chromatography (GC) and gas chromatography-Mass Spectrometry (GC-MS). The fatty acid fractions of different organs (leaves, stems and roots) were characterized by lauric acid (17.9, 17.5 and 18.1 % respectively) and other long chain fatty acids (until C22). Qualitative and quantitative differences were reported between the unsaponifiable fractions of different organs from D. crinitus. The unsaponifiable fractions of the leaves, roots and stem showed high amounts of aliphatic components (83.4%, 87.2% and 91.4%, respectively). The monoterpen, diterpen and sesquiterpen components were only present in small percentages. The antimicrobial properties of the D. critinus extracts were tested on four different microorganisms. These extracts were found to be active against Bacillus cereus, Staphylococcus aureus, Escherichia coli and Candida albicans. (Author) 35 refs.

  7. Numerical simulation of interaction between chemically active exhaust and a jet blast deflector

    Science.gov (United States)

    Korotaeva, T. A.; Turchinovich, A. O.

    2017-10-01

    The interaction of chemically active exhausts of aircraft engines with jet blast deflector (JBD) of various configurations has been considered at the stage of ground run procedure. The problem is modeled in the 3-D approximation in the framework of the numerical solution of the Navier-Stokes equations taking into account the kinetic model of the interaction of between the components of engine exhaust and air. A complex field of gasdynamic flow that is realized when jets emerge from nozzles and interact with each other, with air, with a gas deflector has been studied. The main purpose of the study is to prove the concept that it is possible to generate a vortex flow that can not only change the direction of the jets, but also contribute to the lifting of the mass of pollutants and their dispersion in the atmosphere using a gas deflector shape.

  8. Chemical composition and biological activity of leaves and fruits of Triphasia trifolia

    International Nuclear Information System (INIS)

    Santos, Renata P. dos; Trevisan, Maria Teresa Salles; Silveira, Edilberto R.; Pessoa, Otilia Deusdenia L.; Melo, Vania Maria M.

    2008-01-01

    The chemical composition of the essential oils from leaves and fruits of Triphasia trifolia was analyzed by GC-FID and GC-MS. The major constituents of oil obtained from leaves were sabinene (35.4%) and myrcene (34.1%), while the prevalent compounds in oil from fruits were sabinene (37.2%), β-pinene (23.95) and γg-terpinene (16.3%). Both oils showed moderate antimicrobial activity. The fruit decoction was also investigated leading to the isolation of the coumarins isopimpinelin, (R)-byakangelicin and (S)-mexoticin. From leaves were isolated the coumarins (R)-byakangelicin, aurapten, (S)-mexoticin, isosibiricin, isomerazin and coumurrayin and the flavonoid vitexin. All coumarins showed cholinesterase inhibition on TLC tests. (author)

  9. A systematic chemical separation for thermal neutron activation analysis of seven noble metals in rock

    International Nuclear Information System (INIS)

    Ayabe, Muneo

    1980-01-01

    A method for the systematic activation analysis of seven noble metals - ruthenium, silver, rhenium, osmium, iridium, platinum and gold - in rocks were developed and examined with radiotracers and irradiated rock samples. After the fusion of the irradiated rock sample with sodium hydroxide and sodium peroxide, 10% sodium sulfide solution is added and rhenium is extracted with pyridine-benzene mixture from 6N sodium hydroxide solution. From the hydroxide-sulfide precipitate fraction, ruthenium and osmium are distilled as tetroxides, silver is precipitated as chloride, gold is extracted with ethyl acetate, and iridium and platinum are extracted with diantipyrylmethane. Each fraction is purified and subjected to the γ-ray spectrometry. Chemical yields for the elements are more than 60%. Determination limits are given for the seven elements. (author)

  10. Can phylogeny predict chemical diversity and potential medicinal activity of plants? A case study of Amaryllidaceae

    DEFF Research Database (Denmark)

    Rønsted, Nina; Symonds, Matthew R. E.; Birkholm, Trine

    2012-01-01

    a predictive approach enabling more efficient selection of plants for the development of traditional medicine and lead discovery. However, this relationship has rarely been rigorously tested and the potential predictive power is consequently unknown. Results: We produced a phylogenetic hypothesis......Background: During evolution, plants and other organisms have developed a diversity of chemical defences, leading to the evolution of various groups of specialized metabolites selected for their endogenous biological function. A correlation between phylogeny and biosynthetic pathways could offer...... for the medicinally important plant subfamily Amaryllidoideae (Amaryllidaceae) based on parsimony and Bayesian analysis of nuclear, plastid, and mitochondrial DNA sequences of over 100 species. We tested if alkaloid diversity and activity in bioassays related to the central nervous system are significantly correlated...

  11. Chemical constituents and biological activities of species of Justicia: a review

    Directory of Open Access Journals (Sweden)

    Geone M. Corrêa

    2012-02-01

    Full Text Available The Acanthaceae family is an important source of therapeutic drugs, and the ethnopharmacological knowledge of this family requires urgent documentation as several of its species are near extinction. Justicia is the largest genus of Acanthaceae, with approximately 600 species. The present work provides a review addressing the chemistry and pharmacology of the genus Justicia. In addition, the biological activities of compounds isolated from the genus are also covered. The chemical and pharmacological information in the present work may inspire new biomedical applications for the species of Justicia, considering atom economy, the synthesis of environmentally benign products without producing toxic by-products, the use of renewable sources of raw materials, and the search for processes with maximal efficiency of energy.

  12. Effect of electronegative additives on physical properties and chemical activity of gas discharge plasma

    Science.gov (United States)

    Kuznetsov, D. L.; Filatov, I. E.; Uvarin, V. V.

    2018-01-01

    Effect of electronegative additives (oxygen O2, sulfur dioxide SO2, carbon disulfide CS2, and carbon tetrachloride CCl4) on physical properties and chemical activity of plasma formed by pulsed corona discharge and by non-self-sustained discharge supported by pulsed electron beam in atmospheric pressure gas mixtures was investigated. It is shown that a decrease in discharge current depends on a sort of the additive and on its concentration. The reason is the difference in rate constants of electron attachment processes for the above molecules. In experiments on volatile organic compounds (VOCs) conversion in air by streamer corona it is obtained that an addition of CCl4 both decreases the discharge current amplitude and increases the VOCs conversion degree. An installation for investigation of electron attachment processes and for study of toxic impurities conversion in plasma formed by non-self-sustained discharge initiated by pulsed nanosecond electron beam is created.

  13. Study of grape contamination at the time of harvest using stable chemical substances analyzed by activation

    International Nuclear Information System (INIS)

    Miribel, J.; Delmas, J.

    1989-01-01

    In the sixties the SERE, in conjunction with the French National Institute for Agricultural Research (INRA), conducted experiments on the contamination of wine produced from vines contaminated at the roots. The contamination must be carried out via the leaves and at different stages of growth so as to come as close as possible to the conditions of fall-out. An initial study of grape contamination at the time of the harvest was carried out using stable chemical substances which were analysed by activation. This technique makes it possible to use a large number of substances at the same time and is harmless for the environment. The results obtained appear to be satisfactory, and the method will be used next year for studies at other stages in the ripening of grapes [fr

  14. Influence of Sulfur Fumigation on the Chemical Constituents and Antioxidant Activity of Buds of Lonicera japonica

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    Ai-Li Guo

    2014-10-01

    Full Text Available Lonicera japonica flos is widely used as a pharmaceutical resource and a commonly-employed ingredient in healthy food, soft beverages and cosmetics in China. Sometimes, sulfur fumigation is used during post-harvest handling. In this study, a comprehensive comparison of the chemical profile between sun-dried and sulfur-fumigated samples was conducted by HPLC fingerprints and simultaneous quantification of nine constituents, including secologanic acid, along with another eight usually-analyzed markers. Secologanic acid was destroyed, and its sulfonates were generated, whereas caffeoylquinic acids were protected from being oxidized. The residual sulfur dioxide in sulfur-fumigated samples was significantly higher than that in sun-dried samples, which might increase the potential incidence of toxicity to humans. Meanwhile, compared with sun-dried samples, sulfur-fumigated samples have significantly stronger antioxidant activity, which could be attributed to the joint effect of protected phenolic acids and flavonoids, as well as newly-generated iridoid sulfonates.

  15. Chemical Composition and Antimicrobial Activities of Essential Oils of Some Coniferous Plants Cultivated in Egypt.

    Science.gov (United States)

    Ibrahim, Taghreed A; El-Hela, Atef A; El-Hefnawy, Hala M; Al-Taweel, Areej M; Perveen, Shagufta

    2017-01-01

    Family Cupressaceae is the largest coniferous plant family. Essential oils of many species belonging to family Cupressaceae are known to have several biological activities specially antimicrobial activity. The essential oils from aerial parts of Calocedrus decurrens Torr., Cupressus sempervirens stricta L. and Tetraclinis articulata (Vahl) Mast. were prepared by hydrodistillation. The chemical composition of the essential oils has been elucidated by gas chromatography-mass spectroscopy analysis. The prepared essential oils were examined against selected species of Gram-positive, Gram-negative bacteria and Candida species. Broth dilution methods were used to detect minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and minimum fungicidal concentration (MFC). Sixteen compounds were identified in the essential oils of both Calocedrus decurrens and Cupressus sempervirens L. and fifteen compounds were identified in the essential oil of Tetraclinis articulata . δ-3-Carene (43.10%), (+)-Cedrol (74.03%) and Camphor (21.23%) were the major constituents in the essential oils of Calocedrus decurrens , Cupressus sempervirens L. and Tetraclinis articulata , respectively. The essential oils showed strong antimicrobial activities against the selected microorganisms in concentration range 0.02 3- 3.03 µL/mL. This study could contribute to the chemotaxonomic characterization of family Cupressaceae. In addition, it proved that the essential oils under investigation possess potential antimicrobial properties.

  16. Effect Of GAMMA Radiation On Antimicrobial Activity And Chemical Constituents Of Marjoram (Majorana Hortensis Essential Oil

    International Nuclear Information System (INIS)

    GALAL, Y.G.M.; EL-GHANDOUR, I.A.; ABOU SEER, A.M.M.; DESOUKY, E.M.; ARAFA, R.A.

    2010-01-01

    Field experiment was set up to study the response of marjoram plant grown on sandy soil and inoculated with Bradyrhizobium sp. and/or B. polymixa in combination with organic fertilizers. The extracted oil was irradiated with gamma irradiation at doses of 10, 20, 30, 40 and 50 kGy. The chemical constituents of the essential oils were analyzed by GC-Ms techniques after exposure to gamma radiation. The gamma irradiated essential oils of marjoram were tested for their antimicrobial activities against some pathogenic microorganisms i.e. Klebsiella pneumoniae, Bacillus cereus, Staphylococcus aureus, Salmonella enteritidis, Pseudomonas citri, Fusarium oxysporum, Aspergillus niger, Trichoderma viride and Aspergillus flavus. Extracted oil was the best when soil was treated with faba bean straw and inoculated with B. polymixa + Bradyrhizobium sp. Similarly, the extracted oil from plant cultivated in soil treated with sheep manure in combination with B. polymixa recorded the highest value. Results also revealed that gamma irradiation doses increased the antimicrobial activity with different magnitudes. The essential oil extracted from herb exposed to 30 kGy was found to be the most active antimicrobial with slight increases in the main components.

  17. Evaluation of Chemical Composition and Antileishmanial and Antituberculosis Activities of Essential Oils of Piper Species

    Directory of Open Access Journals (Sweden)

    Karine Zanoli Bernuci

    2016-12-01

    Full Text Available Essential oils from fresh Piperaceae leaves were obtained by hydrodistillation and analyzed by gas chromatography mass spectrometry (GC–MS, and a total of 68 components were identified. Principal components analysis results showed a chemical variability between species, with sesquiterpene compounds predominating in the majority of species analyzed. The composition of the essential oil of Piper mosenii was described for the first time. The cytotoxicity of the essential oils was evaluated in peritoneal macrophages and the oils of P. rivinoides, P. arboretum, and P. aduncum exhibited the highest values, with cytotoxic concentration at 50% (CC50 > 200 µg/mL. Both P. diospyrifolium and P. aduncum displayed activity against Leishmania amazonensis, and were more selective for the parasite than for the macrophages, with a selectivity index (SI of 2.35 and >5.52, respectively. These SI values were greater than the 1 for the standard drug pentamidine. The antileishmanial activity of the essential oils of P. diospyrifolium and P. aduncum was described for the first time. P. rivinoides, P. cernuum, and P. diospyrifolium displayed moderate activity against the Mycobacterium tuberculosis H37Rv bacillus, with a minimum inhibitory concentration (MIC of 125 µg/mL. These results are relevant and suggests their potential for therapeutic purposes. Nevertheless, further studies are required to explain the exact mechanism of action of these essential oils.

  18. Chemical analysis and toxicity of seaweed extracts with inhibitory activity against tropical fruit anthracnose fungi.

    Science.gov (United States)

    Machado, Levi Pompermayer; Matsumoto, Silvia Tamie; Jamal, Claudia Masrouah; da Silva, Marcelo Barreto; Centeno, Danilo da Cruz; Colepicolo Neto, Pio; de Carvalho, Luciana Retz; Yokoya, Nair S

    2014-07-01

    Banana and papaya are among the most important crops in the tropics, with a value amounting to millions of dollars per year. However, these fruits suffer significant losses due to anthracnose, a fungal disease. It is well known that certain seaweed extracts possess antifungal activity, but no published data appear to exist on the practical application of this property. In the present study, five organic Brazilian seaweed extracts were screened for their activity against banana and papaya anthracnose fungi. Furthermore, cytotoxic and mutagenic effects of the extracts were evaluated by the brine shrimp lethality assay and the Allium cepa root-tip mutagenicity test respectively, while their major components were identified by gas chromatography/mass spectrometry. Strong fungus-inhibitory effects of Ochtodes secundiramea and Laurencia dendroidea extracts were observed on both papaya (100 and 98% respectively) and banana (89 and 78% respectively). This impressive activity could be associated with halogenated terpenes, the major components of both extracts. Only Hypnea musciformis extract showed cytotoxic and mutagenic effects. The results of this study suggest the potential use of seaweed extracts as a source of antifungal agents with low toxicity to control anthracnose in papaya and banana during storage. © 2013 Society of Chemical Industry.

  19. Chemical Sensor Platform for Non-Invasive Monitoring of Activity and Dehydration

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    Dmitry Solovei

    2015-01-01

    Full Text Available A non-invasive solution for monitoring of the activity and dehydration of organisms is proposed in the work. For this purpose, a wireless standalone chemical sensor platform using two separate measurement techniques has been developed. The first approach for activity monitoring is based on humidity measurement. Our solution uses new humidity sensor based on a nanostructured TiO2 surface for sweat rate monitoring. The second technique is based on monitoring of potassium concentration in urine. High level of potassium concentration denotes clear occurrence of dehydration. Furthermore, a Wireless Body Area Network (WBAN was developed for this sensor platform to manage data transfer among devices and the internet. The WBAN coordinator controls the sensor devices and collects and stores the measured data. The collected data is particular to individuals and can be shared with physicians, emergency systems or athletes’ coaches. Long-time monitoring of activity and potassium concentration in urine can help maintain the appropriate water intake of elderly people or athletes and to send warning signals in the case of near dehydration. The created sensor system was calibrated and tested in laboratory and real conditions as well. The measurement results are discussed.

  20. Chemical Composition and Biological Activity of Essential Oils of Sempervivum brevipilum Muirhead

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    Nuran Kahriman

    2015-06-01

    Full Text Available The essential oils of the fresh flower, leaf, and stem of Sempervivum brevipilum Muirhead. (Crassulaceae were isolated by hydrodistillation in a modified Clevenger-type apparatus, and characterized by GC-FID and GC-MS. A total of fifty, fourty-three, and thirty-one compounds were identified, constituting over 92.6%, 92.6%, and 94.3% of oil composition of the flower, leaf, and stem of S. brevipilum, respectively. The chemical profile reveals the dominance of hydrocarbons (flower: 65.3%, leaf: 47.6%, stem: 71.1%. The major compounds of essential oils from S. brevipilum were tetracosane (20.2% in flower, 1,2-diphenyl ethandione (16.1% in leaf and docosane (30.5% in stem. Monoterpene hydrocarbons were the major class of terpenoids in flower (2.2% and in stem (1.8%, oxygenated diterpene was the major class of terpenoids in leaf (4.5%. Oxygenated monoterpenes were in minor amounts in all parts (flower: 0.3%, leaf: 0.7%, stem: 0.1% of the plant. In addition, antimicrobial activities of the essential oils of S. brevipilum were investigated. The oils didn’t show any antibacterial and antifungal activity against tested bacteria, but showed high antituberculostatic activity against Mycobacterium smegmatis.

  1. Chemical composition, antioxidant and antimicrobial activities of citrus jambhiri lush and citrus reticulata blanco essential oils

    International Nuclear Information System (INIS)

    Sadaf, S.; Shahid, M.; Iqbal, Z.

    2009-01-01

    The aim of this study was to investigate the time interval in which we can get maximum concentration of essential oil from the peels of Citrus jambhiri Lush and Citrus reticulata Blanco, to determine the composition of peel oils and to evaluate the antioxidant and antimicrobial activity of extracted oils. It was observed that in case of Citrus jambhiri Lush maximum oil yield (I %) was obtained when fruits were immature (during October). As the fruit samples got matured, the oil yield decreased. In December the oil yield decreased to 0.2 %. In case of Citrus reticulata Blanco maximum oil yield (0.189 %) was obtained during the last week of January. Chemical analysis of essential oils showed that limonene was the most abundant compound (86 %-93 %) followed by alpha terpinene (2 %-4.5 %), beta-pinene(1 0/0-2 %) and nerol (0.5 %-1.5 %). The radical scavenging and antioxidant activities of essential oils were determined by DPPH and linoleic acid test. The essential oil of Citrus jambhiri Lush inhibited the oxidation of linoleic acid by 54.98 % and that of Citrus reticulata Blanco inhibited by 49.98 %. Moreover, the essential oils also showed antimicrobial activities against the tested microorganisms. (author)

  2. Caged Garcinia Xanthones, a Novel Chemical Scaffold with Potent Antimalarial Activity.

    Science.gov (United States)

    Ke, Hangjun; Morrisey, Joanne M; Qu, Shiwei; Chantarasriwong, Oraphin; Mather, Michael W; Theodorakis, Emmanuel A; Vaidya, Akhil B

    2017-01-01

    Caged Garcinia xanthones (CGXs) constitute a family of natural products that are produced by tropical/subtropical trees of the genus Garcinia CGXs have a unique chemical architecture, defined by the presence of a caged scaffold at the C ring of a xanthone moiety, and exhibit a broad range of biological activities. Here we show that synthetic CGXs exhibit antimalarial activity against Plasmodium falciparum, the causative parasite of human malaria, at the intraerythrocytic stages. Their activity can be substantially improved by attaching a triphenylphosphonium group at the A ring of the caged xanthone. Specifically, CR135 and CR142 were found to be highly effective antimalarial inhibitors, with 50% effective concentrations as low as ∼10 nM. CGXs affect malaria parasites at multiple intraerythrocytic stages, with mature stages (trophozoites and schizonts) being more vulnerable than immature rings. Within hours of CGX treatment, malaria parasites display distinct morphological changes, significant reduction of parasitemia (the percentage of infected red blood cells), and aberrant mitochondrial fragmentation. CGXs do not, however, target the mitochondrial electron transport chain, the target of the drug atovaquone and several preclinical candidates. CGXs are cytotoxic to human HEK293 cells at the low micromolar level, which results in a therapeutic window of around 150-fold for the lead compounds. In summary, we show that CGXs are potent antimalarial compounds with structures distinct from those of previously reported antimalarial inhibitors. Our results highlight the potential to further develop Garcinia natural product derivatives as novel antimalarial agents. Copyright © 2016 American Society for Microbiology.

  3. Chemical composition and antioxidant activity of Origanum vulgare subsp. vulgare essential oil from Iran

    Directory of Open Access Journals (Sweden)

    M. Vazirian

    2015-12-01

    Full Text Available Background and Objectives: Essential oils are very complex mixture of components and their composition may vary in different species or varieties or even within the same variety. Origanum vulgare L. subsp. vulgare is one of the most distributed subspecies within the genus Origanum and has been found to be a poor-oil, categorized in cymyl, bornane or sabinyl chemotypes with higher proportion of sesquiterpenes. In this experiment, the Iranian sample was studied for the chemical composition of the oil and evaluation of its antioxidant activity. Methods: Essential oil was obtained by hydro-distillation and analyzed by GC/MS for determination of components. Antioxidant activity was evaluated by radical scavenging ability (DPPH method and reducing power (FRAP assay. Results: The sample belonged to “thymol” chemotype with the main components as thymol (37.13%, gama-terpinene (9.67%, carvacrol (9.57%, carvacrol methyl ether (6.88, cis-alpha-bisabolene (6.80%, eucalyptol (3.82%, p-cymene (3.58% and elemol (2.04%. The oil of plant showed very strong antioxidant activity (IC50=2.5 µg/mL in DPPH method, which was stronger than the standard antioxidants (Vit E and BHA, p

  4. Chemical Composition and Antioxidant Activity of Essential Oils from Cinnamodendron dinisii Schwacke and Siparuna guianensis Aublet

    Directory of Open Access Journals (Sweden)

    Milene Aparecida Andrade

    2013-11-01

    Full Text Available The objectives of this study were to chemically characterize and evaluate the antioxidant activity of essential oils Cinnamodendron dinisii Schwacke (pepper and Siparuna guianensis Aublet (negramina. The essential oil was isolated by hydrodistillation using a Clevenger modified apparatus, and the identification and quantification of constituents, through GC/MS and GC-FID analysis. The antioxidant activity was evaluated using β-carotene/linoleic acid system and the DPPH radical sequestering method. In chromatographic analysis, the majority constituents found in the essential oil of C. dinisii were bicyclic monoterpenes, α-pinene (35.41%, β-pinene (17.81%, sabinene (12.01% and sesquiterpene bicyclogermacrene (7.59%. In the essential oil of the fresh leaves of Siparuna guianensis Aublet, acyclic monoterpene, β-myrcene (13.14%, and sesquiterpenes, germacrene-D (8.68% and bicyclogermacrene (16.71% were identified. The antioxidant activity was low by the β-carotene/linoleic acid test and was not evidenced by the DPPH test, for both oils evaluated.

  5. Chemical composition and antibacterial activity of Cordia verbenacea extracts obtained by different methods.

    Science.gov (United States)

    Michielin, Eliane M Z; Salvador, Ana A; Riehl, Carlos A S; Smânia, Artur; Smânia, Elza F A; Ferreira, Sandra R S

    2009-12-01

    The present study describes the chemical composition and the antibacterial activity of extracts from Cordia verbenacea DC (Borraginaceae), a traditional medicinal plant that grows widely along the southeastern coast of Brazil. The extracts were obtained using different extraction techniques: high-pressure operations and low-pressure methods. The high-pressure technique was applied to obtain C. verbenacea extracts using pure CO(2) and CO(2) with co-solvent at pressures up to 30MPa and temperatures of 30, 40 and 50 degrees C. Organic solvents such as n-hexane, ethyl acetate, ethanol, acetone and dichloromethane were used to obtain extracts by low-pressure processes. The antibacterial activity of the extracts was also subjected to screening against four strains of bacteria using the agar dilution method. The extraction yields were up to 5.0% w/w and up to 8.6% w/w for supercritical fluid extraction with pure CO(2) and with ethyl acetate as co-solvent, respectively, while the low-pressure extraction indicates yields up to 24.0% w/w in the soxhlet extraction using water and aqueous mixture with 50% ethanol as solvents. The inhibitory activity of the extracts in gram-positive bacteria was significantly higher than in gram-negative. The quantification and the identification of the extracts recovered were accomplished using GC/MS analysis. The most important components identified in the extract were artemetin, beta-sitosterol, alpha-humulene and beta-caryophyllene, among others.

  6. Chemical composition, antioxidant properties and anti-cholinesterase activity of Cordia gilletii (Boraginaceae) leaves essential oil.

    Science.gov (United States)

    Bonesi, Marco; Okusa, Philippe N; Tundis, Rosa; Loizzo, Monica R; Menichini, Federica; Stévigny, Caroline; Duez, Pierre; Menichini, Francesco

    2011-02-01

    This study aimed to investigate for the first time the chemical composition, the antioxidant properties and the acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activity of the essential oil from the leaves of Cordia gilletii De Wild (Boraginaceae). The essential oil, characterized by 23 constituents (90.1% of the total oil), was constituted by terpene derivatives (25.6%) and non-terpene derivatives (64.5%), among which aldehydes, fatty acids and alkanes were present with the percentage of 16.5%, 18.8% and 23.1%, respectively. The antioxidant activity of C. gilletii essential oil was screened by two in vitro tests: DPPH and beta-carotene bleaching test. The essential oil revealed antioxidant activity with an IC50 value of 75.0 and 129.9 microg/mL on DPPH radical and beta-carotene decoloration tests, respectively. Moreover, C. gilletii inhibited AChE enzyme with an IC50 value of 105.6 microg/mL.

  7. Chemical composition and antimicrobial activity of the essential oil of Satureja biflora (Lamiaceae

    Directory of Open Access Journals (Sweden)

    Josphat C. Matasyoh

    2007-08-01

    Full Text Available Hydro-distilled essential oil from Satureja biflora (Lamiaceae growing in Kenya was analysed by gas chromatography mass spectrometry (GC-MS and also evaluated for antimicrobial activity. Twenty two compounds which constitute 99.29 % of the total oil were identified. The oil was dominated by monoterpenes, which accounted for 62.02 % of the oil. This monoterpene fraction was characterized by a high percentage of linalool (50.60 % such that this Satureja species can be classified as the linalool chemotype. The other major monoterpenes were α-terpineol (2.80 %, β-ocimene (2.25 %, β-pinene (1.96 % and cis-linalool oxide (1.91 %. Sesquiterpenes present in fairly good amounts are germacrene D (10.63 %, α-cadinol (4.53 %, β-bourbonene (2.33 %, δ-cadinene (2.19 %, τ-cadinol (2.17 %, endo-1-bourbonanol (2.14 % and β-caryophyllene (1.98 %. Aliphatic alcohols and acids accounted for 7.23 % of the oil, of which the major one was linoleic acid (4.48 %. The oil was screened for antimicrobial activity against both gram-positive (Staphylococcus aureus, Bacillus ssp. and gram-negative (Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi, Klebsiella pheumoniae, Proteus mirabilis bacteria and a pathogenic fungus (Candida albicans. To the best of our knowledge nothing concerning the chemical composition and biological activity of the essential oil of S. biflora has been reported.

  8. Chemical composition and antioxidant activity of jatobá-do-cerrado (Hymenaea stigonocarpa Mart. flour

    Directory of Open Access Journals (Sweden)

    Cintia Pereira Da Silva

    2014-09-01

    Full Text Available The Brazilian Savannah, known as "Cerrado," has an extensive biodiversity, but it is under explored. Among the native vegetables is the jatobá-do-cerrado (Hymenaea stigonocarpa Mart., a legume with great potential for exploration for its content of dietary fiber. Legumes are an important source of nutrient compounds, such as phenolic compounds and vitamins that have antioxidant properties. This study aimed at determining the chemical composition and antioxidant activity of the jatobá flour. The jatobá flour showed high fiber content (insoluble and soluble fiber 47.8 and 12.8 g.100 g- 1, respectively, significant amounts of carotenoids such as beta-carotene and lutein, and some minerals such as calcium: 145 mg.100 g- 1, magnesium: 125 mg.100 g- 1, and potassium: 1352 mg.100 g- 1. The jatobá flour extracted with different solvents (water, methanol, and acetone exhibited antioxidant activity by the DPPH, FRAP, and ORAC methods. The solvent used in the extraction affected the total phenolic content and antioxidant activity. Acetone extraction produced the best results. Therefore, the jatobá flour is an ingredient that can be used to develop new products with properties that promote health.

  9. Chemical composition, antioxidant, and antimicrobial activities of essential oil from pine needle (Cedrus deodara).

    Science.gov (United States)

    Zeng, Wei-Cai; Zhang, Zeng; Gao, Hong; Jia, Li-Rong; He, Qiang

    2012-07-01

    The chemical composition of essential oil from pine needles (Cedrus deodara) was determined, and its antioxidant and antimicrobial activities were evaluated. Twenty-three components, representing 95.79% of the oil, were identified by gas chromatography mass spectrometry. The main components include α-terpineol (30.2%), linalool (24.47%), limonene (17.01%), anethole (14.57%), caryophyllene (3.14%), and eugenol (2.14%). Pine needle essential oil showed remarkable antioxidant activity in scavenging free radicals, in lipid peroxidation, and in reducing power assays. Moreover, the essential oil revealed strong antimicrobial activity against typical food-borne microorganisms, with minimum inhibitory concentration and minimum bactericidal concentration values of 0.2 to 1.56 and 0.39 to 6.25 μg/mL, respectively. Transmission electron microscope observation ascertained that the bactericidal mechanism of pine needle essential oil may be the induction of cytoplasmic outflow and plasmolysis. These results suggest that the essential oil from pine needles has potential to be used as a natural antioxidant and antimicrobial agent in food processing. The present study provides a theoretical basis for the potential application of essential oil from pine needles (C. deodara) to be used as a natural resource of antioxidant and antimicrobial agents in food industry. © 2012 Institute of Food Technologists®

  10. Chemical composition and biological activities of leaf and fruit essential oils from Eucalyptus camaldulensis.

    Science.gov (United States)

    Dogan, Gulden; Kara, Nazan; Bagci, Eyup; Gur, Seher

    2017-10-26

    The chemical composition of the essential oils from the leaves and fruit of Eucalyptus camaldulensis grown in Mersin, Turkey was analyzed using gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) techniques. The biological activities (antibacterial and antifungal) were examined using the agar well diffusion method. The main leaf oil constituents were p-cymene (42.1%), eucalyptol (1,8-cineole) (14.1%), α-pinene (12.7%) and α-terpinol (10.7%). The main constituents of the fruit oil were eucalyptol (1,8-cineole) (34.5%), p-cymene (30.0%), α-terpinol (15.1%) and α-pinene (9.0%). Our results showed that both types of oils are rich in terms of monoterpene hydrocarbons and oxygenated monoterpenes. The leaf and fruit essential oils of E. camaldulensis significantly inhibited the growth of Gram-positive (Staphylococcus aureus and Bacillus subtilis) and Gram-negative (Escherichia coli and Streptococcus sp.) bacteria (poils also showed fungicidal activity against Candida tropicalis and C. globrata. Leaf essential oils showed more activity than fruit essential oils, probably due to the higher p-cymene concentration in leaves.

  11. Evaluation of Chemical Composition and Antileishmanial and Antituberculosis Activities of Essential Oils of Piper Species.

    Science.gov (United States)

    Bernuci, Karine Zanoli; Iwanaga, Camila Cristina; Fernandez-Andrade, Carla Maria Mariano; Lorenzetti, Fabiana Brusco; Torres-Santos, Eduardo Caio; Faiões, Viviane Dos Santos; Gonçalves, José Eduardo; do Amaral, Wanderlei; Deschamps, Cícero; Scodro, Regiane Bertin de Lima; Cardoso, Rosilene Fressatti; Baldin, Vanessa Pietrowski; Cortez, Diógenes Aparício Garcia

    2016-12-12

    Essential oils from fresh Piperaceae leaves were obtained by hydrodistillation and analyzed by gas chromatography mass spectrometry (GC-MS), and a total of 68 components were identified. Principal components analysis results showed a chemical variability between species, with sesquiterpene compounds predominating in the majority of species analyzed. The composition of the essential oil of Piper mosenii was described for the first time. The cytotoxicity of the essential oils was evaluated in peritoneal macrophages and the oils of P. rivinoides , P. arboretum , and P. aduncum exhibited the highest values, with cytotoxic concentration at 50% (CC 50 ) > 200 µg/mL. Both P. diospyrifolium and P. aduncum displayed activity against Leishmania amazonensis , and were more selective for the parasite than for the macrophages, with a selectivity index (SI) of 2.35 and >5.52, respectively. These SI values were greater than the 1 for the standard drug pentamidine. The antileishmanial activity of the essential oils of P. diospyrifolium and P. aduncum was described for the first time. P. rivinoides, P. cernuum , and P. diospyrifolium displayed moderate activity against the Mycobacterium tuberculosis H 37 Rv bacillus, with a minimum inhibitory concentration (MIC) of 125 µg/mL. These results are relevant and suggests their potential for therapeutic purposes. Nevertheless, further studies are required to explain the exact mechanism of action of these essential oils.

  12. Study on antibacterial activity of chemically synthesized PANI-Ag-Au nanocomposite

    Energy Technology Data Exchange (ETDEWEB)

    Boomi, Pandi [Department of Industrial Chemistry, School of Chemical Sciences, Alagappa University, Karaikudi 630 003, Tamil Nadu (India); Prabu, Halliah Gurumallesh, E-mail: hgprabu2010@gmail.com [Department of Industrial Chemistry, School of Chemical Sciences, Alagappa University, Karaikudi 630 003, Tamil Nadu (India); Manisankar, Paramasivam [Department of Industrial Chemistry, School of Chemical Sciences, Alagappa University, Karaikudi 630 003, Tamil Nadu (India); Ravikumar, Sundaram [Department of Oceanography and Coastal Area Studies, School of Marine Sciences, Alagappa University, Thondi Campus 623 409, Tamil Nadu (India)

    2014-05-01

    Graphical abstract: - Highlights: • New method of synthesizing PANI-Ag-Au nanocomposite. • Surface Plasmon resonance and formation of composite at nano level were analyzed. • HR-TEM study revealed uniform distribution of nanoparticles. • PANI-Ag-Au nanocomposite exhibited good antibacterial activity. - Abstract: Pristine polyaniline (PANI), PANI-Ag, PANI-Au and PANI-Ag-Au nanocomposites have been successfully synthesized by chemical oxidative polymerization method using aniline as monomer, ammonium persulphate as oxidant and metal (Ag, Au and Ag-Au) colloids. UV-Vis analysis exhibited surface Plasmon resonances of Ag, Au, Ag-Au nanoparticles. FT-IR spectra revealed the shift in peak position of N-H stretching. X-ray diffraction (XRD) results confirm the presence of Ag, Au and Au-Ag nanoparticles. HR-TEM images show nanosizes of Ag, Au, Ag-Au and the incorporation of such nanoparticles into the PANI matrix. Pristine PANI, PANI-Ag, PANI-Au and PANI-Ag-Au nanocomposites were tested for antibacterial activity by agar well diffusion method. PANI-Ag-Au nanocomposite exhibited higher antibacterial activity against both gram-positive [Streptococcus sp. (MTCC 890), Staphylococcus sp. (MTCC 96)] and gram-negative bacteria [Escherichia coli (MTCC 1671) and Klebsiella sp. (MTCC 7407)] when compared with PANI-Ag nanocomposite, PANI-Au nanocomposite and pristine PANI. The novelty of this study is the polymer-bimetal synthesis and its antibacterial potential.

  13. Anticonvulsant activity of B2, an adenosine analog, on chemical convulsant-induced seizures.

    Directory of Open Access Journals (Sweden)

    Min Li

    Full Text Available Epilepsy is a chronic neurological disorder characterized by recurrent seizures. However, approximately one-third of epilepsy patients still suffer from uncontrolled seizures. Effective treatments for epilepsy are yet to be developed. N (6-(3-methoxyl-4-hydroxybenzyl adenine riboside (B2 is a N(6-substitued adenosine analog. Here we describe an investigation of the effects and mechanisms of B2 on chemical convulsant-induced seizures. Seizures were induced in mice by administration of 4-aminopyridine (4-AP, pentylenetetrazol (PTZ, picrotoxin, kainite acid (KA, or strychnine. B2 has a dose-related anticonvulsant effect in these chemical-induced seizure models. The protective effects of B2 include increased latency of seizure onset, decreased seizure occurrence, shorter seizure duration and reduced mortality rate. Radioligand binding and cAMP accumulation assays indicated that B2 might be a functional ligand for both adenosine A1 and A2A receptors. Furthermore, DPCPX, a selective A1 receptor antagonist, but not SCH58261, a selective A2A receptor antagonist, blocked the anticonvulsant effect of B2 on PTZ-induced seizure. c-Fos is a cellular marker for neuronal activity. Immunohistochemical and western blot analyses indicated that B2 significantly reversed PTZ-induced c-Fos expression in the hippocampus. Together, these results indicate that B2 has significant anticonvulsant effects. The anticonvulsant effects of B2 may be attributed to adenosine A1 receptor activation and reduced neuronal excitability in the hippocampus. These observations also support that the use of adenosine receptor agonist may be a promising approach for the treatment of epilepsy.

  14. Advanced Chemical Reduction of Reduced Graphene Oxide and Its Photocatalytic Activity in Degrading Reactive Black 5

    Directory of Open Access Journals (Sweden)

    Christelle Pau Ping Wong

    2015-10-01

    Full Text Available Textile industries consume large volumes of water for dye processing, leading to undesirable toxic dyes in water bodies. Dyestuffs are harmful to human health and aquatic life, and such illnesses as cholera, dysentery, hepatitis A, and hinder the photosynthetic activity of aquatic plants. To overcome this environmental problem, the advanced oxidation process is a promising technique to mineralize a wide range of dyes in water systems. In this work, reduced graphene oxide (rGO was prepared via an advanced chemical reduction route, and its photocatalytic activity was tested by photodegrading Reactive Black 5 (RB5 dye in aqueous solution. rGO was synthesized by dispersing the graphite oxide into the water to form a graphene oxide (GO solution followed by the addition of hydrazine. Graphite oxide was prepared using a modified Hummers’ method by using potassium permanganate and concentrated sulphuric acid. The resulted rGO nanoparticles were characterized using ultraviolet-visible spectrophotometry (UV-Vis, X-ray powder diffraction (XRD, Raman, and Scanning Electron Microscopy (SEM to further investigate their chemical properties. A characteristic peak of rGO-48 h (275 cm−1 was observed in the UV spectrum. Further, the appearance of a broad peak (002, centred at 2θ = 24.1°, in XRD showing that graphene oxide was reduced to rGO. Based on our results, it was found that the resulted rGO-48 h nanoparticles achieved 49% photodecolorization of RB5 under UV irradiation at pH 3 in 60 min. This was attributed to the high and efficient electron transport behaviors of rGO between aromatic regions of rGO and RB5 molecules.

  15. Variation in chemical components and biological activity of Pterocarya fraxinifolia Lam. stems at different developmental stages

    Directory of Open Access Journals (Sweden)

    M. Akhbari

    2017-07-01

    Full Text Available Background and objectives: Pterocarya fraxinifolia Lam. is a deciduous, fast-growing tree from walnut family. The stem barks and fruits of the plant have been used as diaphoretic in traditional medicine. Variation in the quantity and quality of the essential oil and extract of stems of the plant at different developmental stages was evaluated in addition to assessing the antimicrobial, cytotoxic and radical scavenging activities in the present study. Methods: Different developmental stages of the plant’s stem (i.e. vegetative, flowering, immature fruit and mature fruit were subjected to hydro-distillation for obtaining the essential oil. The methanol extract of the samples was obtained by Soxhlet apparatus. Chemical composition of the oils was analyzed by gas chromatography/mass spectroscopy (GC/MS. Antimicrobial activity of the oils and extracts were determined against three Gram-positive and five Gram-negative bacteria and two fungi by disc diffusion method. Antioxidant activity of the samples was evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH and β-carotene assays. Total phenolics content of extracts was determined using Folin-Ciocalteau reagent and cytotoxic effect was determined by brine shrimp lethality bioassay. Results: Hexadecanoic acid was one of the major components in all essential oil samples. All samples showed good antimicrobial activity against tested strains. Antioxidant activity of the extracts was comparable to the synthetic standard (butylated hydroxytoluene. The highest total phenolic content and cytotoxic effect were detected for the mature fruit stage of the plant extract and essential oil, respectively. Conclusion: Showing considerable antioxidant and cytotoxic effects, suggested the plant as a good candidate for further investigations.

  16. Chemical composition, antioxidant and antibacterial activities of essential oils from Ferulago angulata.

    Science.gov (United States)

    Ghasemi Pirbalouti, Abdollah; Izadi, Arezo; Malek Poor, Fatemeh; Hamedi, Behzad

    2016-11-01

    Ferulago angulata Boiss. (Apiaceae), a perennial aromatic herb, grows wild in Iran. The aerial parts of F. angulata are used as a flavouring in foods, especially dairy foods by indigenous people in western and southwestern Iran. This study investigates variation in chemical compositions, antioxidant and antibacterial activities of the essential oils from F. angulata collected from natural habitats in the alpine regions of southwestern Iran. The antimicrobial activity, minimum inhibitory concentration (MIC) and minimum bactericidal (MBC) of the essential oils were evaluated against four bacteria (Bacillus cereus, Listeria monocytogenes, Staphylococcus aureus and Salmonella typhimurium). Antioxidant activity of the oils was determined by DPPH assay. The essential oils were analyzed by GC-FID and GC/MS, which 49 volatile components were identified. There were significant differences between the various populations for oil yield and some main compounds. The major constituents of the essential oils from F. angulata were α-pinene, and cis-β-ocimene. The MICs of the essential oils were within concentration ranges from 62 to 250 μg/mL and the respective MBCs were 125 to > 500 μg/mL. Generally, the oils from F. angulata indicated weak to moderate inhibitory activities against bacteria, especially against Listeria monocytogenes. The highest antioxidant activity was obtained from the oil of the Kallar population (IC 50 value   =   488 μg/mL) and BHT as positive control (IC 50  value =   321 μg/mL). The essential oil of F. angulata could be serving as a potential source of α-pinene and cis-β-ocimene for use in the food, cosmetic and pharmaceutical industries.

  17. Chemical characterisation of Nigerian red propolis and its biological activity against Trypanosoma Brucei.

    Science.gov (United States)

    Omar, Ruwida M K; Igoli, John; Gray, Alexander I; Ebiloma, Godwin Unekwuojo; Clements, Carol; Fearnley, James; Ebel, Ru Angeli Edrada; Zhang, Tong; De Koning, Harry P; Watson, David G

    2016-01-01

    A previous study showed the unique character of Nigerian red propolis from Rivers State, Nigeria (RSN), with regards to chemical composition and activity against Trypanosoma brucei in comparison with other African propolis. To carry out fractionation and biological testing of Nigerian propolis in order to isolate compounds with anti-trypanosomal activity. To compare the composition of the RSN propolis with the composition of Brazilian red propolis. Profiling was carried out using HPLC-UV-ELSD and HPLC-Orbitrap-FTMS on extracts of two samples collected from RSN with data extraction using MZmine software. Isolation was carried out by normal phase and reversed phase MPLC. Elucidation of the compounds with a purity > 95% was performed by 1D/2D NMR HRMS and HRLC-MS(n) . Ten phenolic compounds were isolated or in the case of liquiritigenin partially purified. Data for nine of these correlated with literature reports of known compounds i.e. one isoflavanone, calycosin (1); two flavanones, liquiritigenin (2) and pinocembrin (5); an isoflavan, vestitol (3); a pterocarpan, medicarpin (4); two prenylflavanones, 8-prenylnaringenin (7) and 6-prenylnaringenin (8); and two geranyl flavonoids, propolin D (9) and macarangin (10). The tenth was elucidated as a previously undescribed dihydrobenzofuran (6). The isolated compounds were tested against Trypanosoma brucei and displayed moderate to high activity. Some of the compounds tested had similar activity against wild type T. brucei and two strains displaying pentamidine resistance. Nigerian propolis from RSN has some similarities with Brazilian red propolis. The propolis displayed anti-trypanosomal activity at a potentially useful level. Copyright © 2015 John Wiley & Sons, Ltd.

  18. Chemical Profile and Antioxidant, Anti-Inflammatory, Antimutagenic and Antimicrobial Activities of Geopropolis from the Stingless Bee Melipona orbignyi.

    Science.gov (United States)

    Santos, Helder Freitas Dos; Campos, Jaqueline Ferreira; Santos, Cintia Miranda Dos; Balestieri, José Benedito Perrella; Silva, Denise Brentan; Carollo, Carlos Alexandre; de Picoli Souza, Kely; Estevinho, Leticia Miranda; Dos Santos, Edson Lucas

    2017-05-03

    Geopropolis is a resin mixed with mud, produced only by stingless bees. Despite being popularly known for its medicinal properties, few scientific studies have proven its biological activities. In this context, the objective of this study was to determine the chemical composition and antioxidant, anti-inflammatory, antimutagenic and antimicrobial activities of the Melipona orbignyi geopropolis. The hydroalcoholic extract of geopropolis (HEGP) was prepared and its chemical composition determined by high performance liquid chromatography coupled to diode array detector and mass spectrometry (HPLC-DAD-MS). The antioxidant activity was determined by the capture of free radicals and inhibition of lipid peroxidation in human erythrocytes. The anti-inflammatory activity was evaluated by the inhibition of the hyaluronidase enzyme and the antimutagenic action was investigated in Saccharomyces cerevisiae colonies. The antimicrobial activities were determined against bacteria and yeasts, isolated from reference strains and hospital origin. The chemical composition of HEGP included flavonoids, derivatives of glycosylated phenolic acids and terpenoids. HEGP showed high antioxidant activity, it inhibited the activity of the inflammatory enzyme hyaluronidase and reduced the mutagenic effects in S. cerevisiae . In relation to the antimicrobial activity, it promoted the death of all microorganisms evaluated. In conclusion, this study reveals for the first time the chemical composition of the HEGP of M. orbignyi and demonstrates its pharmacological properties.

  19. Matching Element Symbols with State Abbreviations: A Fun Activity for Browsing the Periodic Table of Chemical Elements

    Science.gov (United States)

    Woelk, Klaus

    2009-01-01

    A classroom activity is presented in which students are challenged to find matches between the United States two-letter postal abbreviations for states and chemical element symbols. The activity aims to lessen negative apprehensions students might have when the periodic table of the elements with its more than 100 combinations of letters is first…

  20. Chemical Profile and Antioxidant, Anti-Inflammatory, Antimutagenic and Antimicrobial Activities of Geopropolis from the Stingless Bee Melipona orbignyi

    Science.gov (United States)

    dos Santos, Helder Freitas; Campos, Jaqueline Ferreira; dos Santos, Cintia Miranda; Balestieri, José Benedito Perrella; Silva, Denise Brentan; Carollo, Carlos Alexandre; de Picoli Souza, Kely; Estevinho, Leticia Miranda; dos Santos, Edson Lucas

    2017-01-01

    Geopropolis is a resin mixed with mud, produced only by stingless bees. Despite being popularly known for its medicinal properties, few scientific studies have proven its biological activities. In this context, the objective of this study was to determine the chemical composition and antioxidant, anti-inflammatory, antimutagenic and antimicrobial activities of the Melipona orbignyi geopropolis. The hydroalcoholic extract of geopropolis (HEGP) was prepared and its chemical composition determined by high performance liquid chromatography coupled to diode array detector and mass spectrometry (HPLC-DAD-MS). The antioxidant activity was determined by the capture of free radicals and inhibition of lipid peroxidation in human erythrocytes. The anti-inflammatory activity was evaluated by the inhibition of the hyaluronidase enzyme and the antimutagenic action was investigated in Saccharomyces cerevisiae colonies. The antimicrobial activities were determined against bacteria and yeasts, isolated from reference strains and hospital origin. The chemical composition of HEGP included flavonoids, derivatives of glycosylated phenolic acids and terpenoids. HEGP showed high antioxidant activity, it inhibited the activity of the inflammatory enzyme hyaluronidase and reduced the mutagenic effects in S. cerevisiae. In relation to the antimicrobial activity, it promoted the death of all microorganisms evaluated. In conclusion, this study reveals for the first time the chemical composition of the HEGP of M. orbignyi and demonstrates its pharmacological properties. PMID:28467350

  1. Efficacy from Different Extractions for Chemical Profile and Biological Activities of Rice Husk

    Directory of Open Access Journals (Sweden)

    Truong Ngoc Minh

    2018-04-01

    Full Text Available Rice husk is a by-product produced abundantly in rice production but it has low commercial value and causes environmental pollution. This study was conducted to examine different extracting solvents and conditions to optimize the efficacy of antioxidant and antimicrobial potentials, and chemical components in rice husk. By the use of distilled water at 100 °C, the ethyl acetate (EtOAc extract was potent in both total phenolic content (TPC, total flavonoid content (TFC, and DPPH scavenging activity. The treatment of either ethyl acetate (100 °C, 1 h, combined with MeOH 100%, showed the highest percent of lipid peroxidation inhibition (LPI (86%, meaning that the strongest antioxidant activity was by the β-carotene bleaching method. The treatment of distilled water at room temperature possessed the strongest antioxidant activity in the assay of the reducing power. The use of dried samples at 100 °C for 2 h, combined with methanol (MeOH 10%, provided the most potent antimicrobial activities against Escherichia coli, Klebsiella pneumoniae, Listeria monocytogenes, Bacillus subtilis, and Proteus mirabilis. The results suggested that the EtOAc extract from rice husk could be a potential source of natural antioxidants. In general, the use of temperature 100 °C for 2 h, combined with either EtOAc or 10% MeOH, can optimize chemical components and antioxidant and antimicrobial capacities in rice husk. Principal constituents putatively identified by gas chromatography–mass spectrometry (GC–MS revealed the presence of momilactones A and B (MA and MB, respectively, phenols, phenolic acids, and long-chain fatty acids, although yields of these compounds varied among extracts. The bioactive MA and MB were found in most of the extracts, except distilled water and MeOH ≤ 50%, at any temperature. Findings of this study provided optimal conditions for future production at an industrial scale for rice husk to exploit its potent biological properties. It

  2. The active site of hen egg-white lysozyme: flexibility and chemical bonding

    Energy Technology Data Exchange (ETDEWEB)

    Held, Jeanette, E-mail: jeanette.netzel@uni-bayreuth.de; Smaalen, Sander van [University of Bayreuth, D-95440 Bayreuth (Germany)

    2014-04-01

    Chemical bonding at the active site of lysozyme is analyzed on the basis of a multipole model employing transferable multipole parameters from a database. Large B factors at low temperatures reflect frozen-in disorder, but therefore prevent a meaningful free refinement of multipole parameters. Chemical bonding at the active site of hen egg-white lysozyme (HEWL) is analyzed on the basis of Bader’s quantum theory of atoms in molecules [QTAIM; Bader (1994 ▶), Atoms in Molecules: A Quantum Theory. Oxford University Press] applied to electron-density maps derived from a multipole model. The observation is made that the atomic displacement parameters (ADPs) of HEWL at a temperature of 100 K are larger than ADPs in crystals of small biological molecules at 298 K. This feature shows that the ADPs in the cold crystals of HEWL reflect frozen-in disorder rather than thermal vibrations of the atoms. Directly generalizing the results of multipole studies on small-molecule crystals, the important consequence for electron-density analysis of protein crystals is that multipole parameters cannot be independently varied in a meaningful way in structure refinements. Instead, a multipole model for HEWL has been developed by refinement of atomic coordinates and ADPs against the X-ray diffraction data of Wang and coworkers [Wang et al. (2007), Acta Cryst. D63, 1254–1268], while multipole parameters were fixed to the values for transferable multipole parameters from the ELMAM2 database [Domagala et al. (2012), Acta Cryst. A68, 337–351] . Static and dynamic electron densities based on this multipole model are presented. Analysis of their topological properties according to the QTAIM shows that the covalent bonds possess similar properties to the covalent bonds of small molecules. Hydrogen bonds of intermediate strength are identified for the Glu35 and Asp52 residues, which are considered to be essential parts of the active site of HEWL. Furthermore, a series of weak C

  3. Chemical composition, immunostimulatory, cytotoxic and antiparasitic activities of the essential oil from Brazilian red propolis.

    Science.gov (United States)

    Sena-Lopes, Ângela; Bezerra, Francisco Silvestre Brilhante; das Neves, Raquel Nascimento; de Pinho, Rodrigo Barros; Silva, Mara Thais de Oliveira; Savegnago, Lucielli; Collares, Tiago; Seixas, Fabiana; Begnini, Karine; Henriques, João Antonio Pêgas; Ely, Mariana Roesch; Rufatto, Luciane C; Moura, Sidnei; Barcellos, Thiago; Padilha, Francine; Dellagostin, Odir; Borsuk, Sibele

    2018-01-01

    Most studies of Brazilian red propolis have explored the composition and biological properties of its ethanolic extracts. In this work, we chemically extracted and characterized the essential oil of Brazilian red propolis (EOP) and assessed its adjuvant, antiparasitic and cytotoxic activities. The chemical composition of EOP was analyzed using gas chromatography with mass spectrometry (GC-MS). EOP was tested for in vitro activity against Trichomonas vaginalis (ATCC 30236 isolate); trophozoites were treated with different concentrations of EOP (ranging from 25 to 500 μg/mL) in order to establish the MIC and IC50 values. A cytotoxicity assay was performed in CHO-K1 cells submitted to different EOP concentrations. BALB/c mice were used to test the adjuvant effect of EOP. The animals were divided in 3 groups and inoculated as follows: 0.4 ng/kg BW EOP (G1); 50 μg of rCP40 protein (G2); or a combination of 0.4 ng/kg BW EOP and 50 μg of rCP40 (G3). Total IgG, IgG1 and IgG2a levels were assessed by ELISA. The major constituent compounds of EOP were methyl eugenol (13.1%), (E)-β-farnesene (2.50%), and δ-amorphene (2.3%). Exposure to EOP inhibited the growth of T. vaginalis, with an IC50 value of 100 μg/mL of EOP. An EOP concentration of 500 μg/mL was able to kill 100% of the T. vaginalis trophozoites. The EOP kinetic growth curve showed a 36% decrease in trophozoite growth after a 12 h exposure to 500 μg/mL of EOP, while complete parasite death was induced at 24 h. With regard to CHO-K1 cells, the CC50 was 266 μg/mL, and 92% cytotoxicity was observed after exposure to 500 μg/mL of EOP. Otherwise, a concentration of 200 μg/mL of EOP was able to reduce parasite proliferation by 70% and was not cytotoxic to CHO-K1 cells. As an adjuvant, a synergistic effect was observed when EOP was combined with the rCP40 protein (G3) in comparison to the administration of each component alone (G1 and G2), resulting in higher concentrations of IgG, IgG1 and IgG2a. EOP is

  4. Chemical composition, immunostimulatory, cytotoxic and antiparasitic activities of the essential oil from Brazilian red propolis.

    Directory of Open Access Journals (Sweden)

    Ângela Sena-Lopes

    Full Text Available Most studies of Brazilian red propolis have explored the composition and biological properties of its ethanolic extracts. In this work, we chemically extracted and characterized the essential oil of Brazilian red propolis (EOP and assessed its adjuvant, antiparasitic and cytotoxic activities. The chemical composition of EOP was analyzed using gas chromatography with mass spectrometry (GC-MS. EOP was tested for in vitro activity against Trichomonas vaginalis (ATCC 30236 isolate; trophozoites were treated with different concentrations of EOP (ranging from 25 to 500 μg/mL in order to establish the MIC and IC50 values. A cytotoxicity assay was performed in CHO-K1 cells submitted to different EOP concentrations. BALB/c mice were used to test the adjuvant effect of EOP. The animals were divided in 3 groups and inoculated as follows: 0.4 ng/kg BW EOP (G1; 50 μg of rCP40 protein (G2; or a combination of 0.4 ng/kg BW EOP and 50 μg of rCP40 (G3. Total IgG, IgG1 and IgG2a levels were assessed by ELISA. The major constituent compounds of EOP were methyl eugenol (13.1%, (E-β-farnesene (2.50%, and δ-amorphene (2.3%. Exposure to EOP inhibited the growth of T. vaginalis, with an IC50 value of 100 μg/mL of EOP. An EOP concentration of 500 μg/mL was able to kill 100% of the T. vaginalis trophozoites. The EOP kinetic growth curve showed a 36% decrease in trophozoite growth after a 12 h exposure to 500 μg/mL of EOP, while complete parasite death was induced at 24 h. With regard to CHO-K1 cells, the CC50 was 266 μg/mL, and 92% cytotoxicity was observed after exposure to 500 μg/mL of EOP. Otherwise, a concentration of 200 μg/mL of EOP was able to reduce parasite proliferation by 70% and was not cytotoxic to CHO-K1 cells. As an adjuvant, a synergistic effect was observed when EOP was combined with the rCP40 protein (G3 in comparison to the administration of each component alone (G1 and G2, resulting in higher concentrations of IgG, IgG1 and IgG2a. EOP is

  5. The active site of hen egg-white lysozyme: flexibility and chemical bonding

    International Nuclear Information System (INIS)

    Held, Jeanette; Smaalen, Sander van

    2014-01-01

    Chemical bonding at the active site of lysozyme is analyzed on the basis of a multipole model employing transferable multipole parameters from a database. Large B factors at low temperatures reflect frozen-in disorder, but therefore prevent a meaningful free refinement of multipole parameters. Chemical bonding at the active site of hen egg-white lysozyme (HEWL) is analyzed on the basis of Bader’s quantum theory of atoms in molecules [QTAIM; Bader (1994 ▶), Atoms in Molecules: A Quantum Theory. Oxford University Press] applied to electron-density maps derived from a multipole model. The observation is made that the atomic displacement parameters (ADPs) of HEWL at a temperature of 100 K are larger than ADPs in crystals of small biological molecules at 298 K. This feature shows that the ADPs in the cold crystals of HEWL reflect frozen-in disorder rather than thermal vibrations of the atoms. Directly generalizing the results of multipole studies on small-molecule crystals, the important consequence for electron-density analysis of protein crystals is that multipole parameters cannot be independently varied in a meaningful way in structure refinements. Instead, a multipole model for HEWL has been developed by refinement of atomic coordinates and ADPs against the X-ray diffraction data of Wang and coworkers [Wang et al. (2007), Acta Cryst. D63, 1254–1268], while multipole parameters were fixed to the values for transferable multipole parameters from the ELMAM2 database [Domagala et al. (2012), Acta Cryst. A68, 337–351] . Static and dynamic electron densities based on this multipole model are presented. Analysis of their topological properties according to the QTAIM shows that the covalent bonds possess similar properties to the covalent bonds of small molecules. Hydrogen bonds of intermediate strength are identified for the Glu35 and Asp52 residues, which are considered to be essential parts of the active site of HEWL. Furthermore, a series of weak C

  6. 75 FR 8266 - Final Clarification for Chemical Identification Describing Activated Phosphors for TSCA Inventory...

    Science.gov (United States)

    2010-02-24

    ... mixture of metal oxides, carbonates, phosphates or acid phosphates, chlorides, and/or fluorides, most... normally included with a new chemical notice submission, such as toxicity data on the chemical substance...

  7. Chemical Constituents and Activity of Murraya microphylla Essential Oil against Lasioderma serricorne.

    Science.gov (United States)

    You, Chun-Xue; Guo, Shan-Shan; Zhang, Wen-Juan; Yang, Kai; Wang, Cheng-Fang; Geng, Zhu-Feng; Du, Shu-Shan; Deng, Zhi-Wei; Wang, Yong-Yan

    2015-09-01

    The chemical composition, contact and repellent activities of the essential oil from Murraya microphylla branches and leaves against Lasioderma serricorne adults were determined and six compounds from the essential oil were isolated as well. The essential oil of M microphylla obtained by hydrodistillation was analyzed by gas chromatography-mass spectrometric (GC-MS) analysis; 22 compounds were identified. The main constituents of the essential oil included β-caryophyllene (18.0%), α-pinene (13.8%), spathulenol (9.5%), α-humulene (6.0%), γ-elemene (5.1%) and zingiberene (4.6%), followed by α-cadinol (3.9%) and caryophyllene oxide (3.8%). Six of these compounds were isolated and fully identified as α-pinene, β-caryophyllene, α-humulene, caryophyllene oxide, spathulenol and α-cadinol. L. serricorne adults had different sensitivities to the crude essential oil and isolated compounds. α-Humulene exhibited the strongest contact activity against L. serricorne, showing an LD50 value of 13.1 µg adult(-1). However, spathulenol, the crude essential oil and α-cadinol showed stronger contact activity against L. serricorne than caryophyllene oxide and β-caryophyllene. The essential oil, α-humulene and spathulenol showed comparable repellency against L. serricorne adults at 2 h after exposure, relative to the positive control, DEET. The results demonstrate that the essential oil and isolated compounds exhibited important contact and repellent activities against L. serricorne. Thus, they could become potential natural insecticides or repellents for control of insects in stored products.

  8. Chemical Constituents from the Branches of Carpinus turczaninowii with Antioxidative Activities

    International Nuclear Information System (INIS)

    Ko, Ha Na; Kim, Jung Mi; Bu, Hee Jung; Lee, Nam Ho

    2013-01-01

    Eight compounds were identified in ethanol extracts prepared from the branches of C. turczaninowii. The compounds, besides 5 and 6, were isolated for the first time from this woody plant. Pyracrenic acid (4) and quercitrin (8) showed potent DPPH free radical scavenging activities with SC 50 values of 55.2 and 62.4 μM, respectively, where ascorbic acid (SC 50 43.5 μM) was used as a positive control. Compounds 4, 5, 6 and 8 showed strong activities in ABTS + radical scavenging assay, with SC 50 values of 34.1, 42.1, 45.8 and 29.6 μM, respectively. These activities are comparable in potency to ascorbic acid (SC 50 31.6 μM). Based on these results, C. turczaninowii extracts are expected to be useful antioxidative agents, potentially applicable in food or cosmetic industries, based on the results of further studies. Korean hornbeam Carpinus turczaninowii is a deciduous woody plant belonging to the family Betulaceae. This flora is endemic to Korea, and can reach a height of 15 m. In the autumn, the fallen leaves of C. turczaninowii display a beautiful orange-red color and the tree is commonly used for bonsai in Korea. The wood is very hard, dense and fine textured, and has been used for making agricultural tools and furniture. Previous chemical investigation on this plant indicated only the existence of flavonoids such as naringenin and quercetin glycosides from the leaves. We have recently reported the isolation diarylheptanoids possessing anti-inflammatory activities from the ethanol extract of C. turczaninowii

  9. Chemical Constituents from the Branches of Carpinus turczaninowii with Antioxidative Activities

    Energy Technology Data Exchange (ETDEWEB)

    Ko, Ha Na; Kim, Jung Mi; Bu, Hee Jung; Lee, Nam Ho [Jeju National Univ., Jeju (Korea, Republic of)

    2013-08-15

    Eight compounds were identified in ethanol extracts prepared from the branches of C. turczaninowii. The compounds, besides 5 and 6, were isolated for the first time from this woody plant. Pyracrenic acid (4) and quercitrin (8) showed potent DPPH free radical scavenging activities with SC{sub 50} values of 55.2 and 62.4 μM, respectively, where ascorbic acid (SC{sub 50} 43.5 μM) was used as a positive control. Compounds 4, 5, 6 and 8 showed strong activities in ABTS{sup +} radical scavenging assay, with SC{sub 50} values of 34.1, 42.1, 45.8 and 29.6 μM, respectively. These activities are comparable in potency to ascorbic acid (SC{sub 50} 31.6 μM). Based on these results, C. turczaninowii extracts are expected to be useful antioxidative agents, potentially applicable in food or cosmetic industries, based on the results of further studies. Korean hornbeam Carpinus turczaninowii is a deciduous woody plant belonging to the family Betulaceae. This flora is endemic to Korea, and can reach a height of 15 m. In the autumn, the fallen leaves of C. turczaninowii display a beautiful orange-red color and the tree is commonly used for bonsai in Korea. The wood is very hard, dense and fine textured, and has been used for making agricultural tools and furniture. Previous chemical investigation on this plant indicated only the existence of flavonoids such as naringenin and quercetin glycosides from the leaves. We have recently reported the isolation diarylheptanoids possessing anti-inflammatory activities from the ethanol extract of C. turczaninowii.

  10. Chemical characterization and antioxidant activities comparison in fresh, dried, stir-frying and carbonized ginger.

    Science.gov (United States)

    Li, Yuxin; Hong, Yan; Han, Yanquan; Wang, Yongzhong; Xia, Lunzhu

    2016-02-01

    Ginger (Zingiber officinale Rosc.) is a common dietary adjunct that contributes to the taste and flavor of foods, and is also an important Traditional Chinese medicine (TCM). Different processing methods can produce different processed gingers with dissimilar chemical constituents and pharmacological activities. In this study, an ultra-performance liquid chromatography/quadrupole-time-of-flight mass spectrometry (UPLC/QTOF-MS) was applied to identify the complicated components from fresh, dried, stir-frying and carbonized ginger extracts. All of the 27 compounds were identified from four kinds of ginger samples (fresh, dried, stir-frying and carbonized ginger). Five main constituents (zingerone, 6-gingerol, 8-gingerol, 6-shogaol and 10-gingerol) in these four kinds of ginger sample extracts were simultaneously determined by UPLC-PDA. Meanwhile, the antioxidant effect of fresh, dried, stir-frying and carbonized gingers were evaluated by three assays (2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azinobis(3-ethylbenzthiazolinesulfonic acid) diammonium salt (ABTS), and ferric reducing antioxidant power (FRAP)). The results demonstrated that antioxidant activity of dried ginger was the highest, for its phenolic contents are 5.2-, 1.1- and 2.4-fold higher than that of fresh, stir-frying and carbonized ginger, respectively, the antioxidant activities' results indicated a similar tendency with phenolic contents: dried ginger>stir-frying ginger>fresh ginger>carbonized ginger. The processing contributed to the decreased concentration of gingerols and the increased levels of shogaols, which reducing the antioxidant effects in pace with processing. This study elucidated the relationship of the heating process with the constituents and antioxidant activity, and provided a guide for choosing different kinds of ginger samples on clinical application. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Chemical Composition and Antioxidant Activity in Different Tissues of Brassica Vegetables

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    Shiva Ram Bhandari

    2015-01-01

    Full Text Available This research was conducted to evaluate glucosinolate profiles, vitamin C, total phenol, total flavonoid, and free sugar (glucose, fructose, and sucrose content, fatty acid composition, and antioxidant activity in floret and leaf of six cauliflower and broccoli cultivars. The level of chemical constituents as well as antioxidants significantly varied among crop types, cultivars, and their different parts, in that phytochemicals such as glucosinolate were statistically higher in florets compared with leaves in both broccoli and cauliflower cultivars. In contrast, total flavonoid and free sugar were found at higher levels in the leaf parts. The Asia purple cultivar exhibited statistically higher vitamin C (649.7 mg·100 g−1, total phenol (1345.2 mg·GAE 100 g−1, and total flavonoid (632.7 mg·CE 100 g−1 contents and consequently had the highest antioxidant activity (1.12 mg·mL−1 in its florets, while Baeridom and Bridal had the highest total glucosinolate (9.66 µmol·g−1 and free sugar (318.6 mg·g−1 contents, respectively compared with other cultivars. Likewise, the major fatty acids were palmitic (23.52%–38.42%, linoleic (13.09%–18.97%, and linolenic (26.32%–51.80% acids, which comprised the highest compositional ratio (more than 50% of polyunsaturated fatty acids (PUFAs in most cultivars. Among the antioxidants, total phenol exhibited the most significant positive correlation (r = 0.698 ** with antioxidant activity, followed by vitamin C (r = 0.522 ** and total flavonoid (r = 0.494 **, indicating their significant contributions to total antioxidant activity.

  12. A Rat α-Fetoprotein Binding Activity Prediction Model to Facilitate Assessment of the Endocrine Disruption Potential of Environmental Chemicals.

    Science.gov (United States)

    Hong, Huixiao; Shen, Jie; Ng, Hui Wen; Sakkiah, Sugunadevi; Ye, Hao; Ge, Weigong; Gong, Ping; Xiao, Wenming; Tong, Weida

    2016-03-25

    Endocrine disruptors such as polychlorinated biphenyls (PCBs), diethylstilbestrol (DES) and dichlorodiphenyltrichloroethane (DDT) are agents that interfere with the endocrine system and cause adverse health effects. Huge public health concern about endocrine disruptors has arisen. One of the mechanisms of endocrine disruption is through binding of endocrine disruptors with the hormone receptors in the target cells. Entrance of endocrine disruptors into target cells is the precondition of endocrine disruption. The binding capability of a chemical with proteins in the blood affects its entrance into the target cells and, thus, is very informative for the assessment of potential endocrine disruption of chemicals. α-fetoprotein is one of the major serum proteins that binds to a variety of chemicals such as estrogens. To better facilitate assessment of endocrine disruption of environmental chemicals, we developed a model for α-fetoprotein binding activity prediction using the novel pattern recognition method (Decision Forest) and the molecular descriptors calculated from two-dimensional structures by Mold² software. The predictive capability of the model has been evaluated through internal validation using 125 training chemicals (average balanced accuracy of 69%) and external validations using 22 chemicals (balanced accuracy of 71%). Prediction confidence analysis revealed the model performed much better at high prediction confidence. Our results indicate that the model is useful (when predictions are in high confidence) in endocrine disruption risk assessment of environmental chemicals though improvement by increasing number of training chemicals is needed.

  13. Chemical composition and antimicrobial activity of essential oils of Ocimum canum Sims. and Ocimum selloi Benth.

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    Jeferson C. Nascimento

    2011-09-01

    Full Text Available This work describes the chemical composition and antimicrobial activity of the volatile oils of Ocimum canum and Ocimum selloi, both occurring in Jequié/BA, northeastern Brazil. The plants were collected in the winter/2005 andsummer/2006, the oils extracted by steam distillation and further analyzed by GC-MS. A total of 30 and 31 compounds was identified from the oils of O. selloi and O. canum, respectively. It was observed that the oil content of O. canum showed variation during the seasons, while the oils of O. selloi did not. Methylchavicol and linalool were the main chemical components found in the aerial parts and leaves of O. canum. This finding permitted to characterize this specimen as a new chemotype of O. canum. Regarding the aerial parts of O. selloi, eugenol, 1,8-cineole, transcaryophyllene and linalool were identified as their major components. All extracted oils from the aerial parts showed biological activity against gram-positive cocci - Staphylococcus aureus ATCC 25923 - but only the O. canum one showed activity against gram-negative bacilli - Escherichia coli ATCC 25922.Este trabalho descreve a composição química e a atividade antimicrobiana dos óleos voláteis de Ocimum canum e Ocimum selloi, que ocorrem em Jequié/BA, nordeste do Brasil. As plantas foram colhidas no inverno de 2005 e verão de 2006 e os óleos extraídos por destilação a vapor foram posteriormente analisados por GC-MS. Um total de 30 e 31 compostos foi identificado a partir dos óleos de O. selloi e O. canum, respectivamente. Foi observado que o teor de óleo de O. canum apresentou variação durante as estações do ano, enquanto o óleo de O. selloi não. Metilchavicol e linalol foram os principais componentes químicos encontrados na parte aérea e folhas de O. canum. Esta descoberta permitiu caracterizar este espécime como um novo quimiotipo de O. canum. Com relação às partes aéreas de O. selloi, eugenol, 1,8-cineol, trans-cariofileno e

  14. Hydrogen determination in chemically delithiated lithium ion battery cathodes by prompt gamma activation analysis

    Science.gov (United States)

    Alvarez, Emilio, II

    2007-12-01

    Lithium ion batteries, due to their relatively high energy density, are now widely used as the power source for portable electronics. Commercial lithium ion cells currently employ layered LiCoO2 as a cathode but only 50% of its theoretical capacity can be utilized. The factors that cause the limitation are not fully established in the literature. With this perspective, prompt gamma-ray activation analysis (PGAA) has been employed to determine the hydrogen content in various oxide cathodes that have undergone chemical extraction of lithium (delithiation). The PGAA data is complemented by data obtained from atomic absorption spectroscopy (AAS), redox titration, thermogravimetric analysis (TGA), and mass spectroscopy to better understand the capacity limitations and failure mechanisms of lithium ion battery cathodes. As part of this work, the PGAA facility has been redesigned and reconstructed. The neutron and gamma-ray backgrounds have been reduced by more than an order of magnitude. Detection limits for elements have also been improved. Special attention was given to the experimental setup including potential sources of error and system calibration for the detection of hydrogen. Spectral interference with hydrogen arising from cobalt was identified and corrected for. Limits of detection as a function of cobalt mass present in a given sample are also discussed. The data indicates that while delithiated layered Li1- xCoO2, Li1-xNi 1/3Mn1/3Co1/3O2, and Li1- xNi0.5Mn0.5O2 take significant amounts of hydrogen into the lattice during deep extraction, orthorhombic Li 1-xMnO2, spinel Li1- xMn2O4, and olivine Li1- xFePO4 do not. Layered LiCoO2, LiNi 0.5Mn0.5O2, and LiNi1/3Mn1/3Co 1/3O2 have been further analyzed to assess their relative chemical instabilities while undergoing stepped chemical delithiation. Each system takes increasing amounts of protons at lower lithium contents. The differences are attributed to the relative chemical instabilities of the various cathodes

  15. Wine Chemical Composition and Radical Scavenging Activity of Some Cabernet Franc Clones.

    Science.gov (United States)

    Popovic-Djordjevic, Jelena; Pejin, Boris; Dramicanin, Aleksandra; Jovic, Sonja; Vujovic, Dragan; Zunic, Dragoljub; Ristic, Renata

    2017-01-01

    Three clones of Cabernet Franc (Nos. 02, 010 and 012) were selected in the last phase of clonal selection in Serbia. Wines made from each clone were assessed for quality parameters and taste during five consecutive vintages (2008-2012) and compared to the standard. The wine quality was determined based on the following parameters: alcohol, total extract, anthocyanins, tannins, pH, titratable acidity, volatile acidity, aldehydes, esters and reducing sugars, relative density, ash, colour, tonality, and tasting score. In the last year of the study, grapes and wines of Cabernet Franc clones and a standard were subjected to a chemical analysis of their phenolic composition, resveratrol and radical scavenging activity. In the last year of the study, grapes and wines of Cabernet Franc clones and a standard were subjected to a chemical analysis of their phenolic composition, resveratrol and radical scavenging activity. Chemical analyses of grapes and wines along with sensory and radical scavenging activity evaluations were done according to the standard procedures. The wines of the clone No. 010 showed some superior properties compared to the other two clones and the standard; in five-year period the average concentration of anthocyanins (179±3.8 mg/L) and polyphenolics (1.85±0.02 g/L) was significantly higher than in wines of clones and the standard, (168-173 mg/L and 1.63-1.74 g/L for anthocyanins and phenolics, respectively). Furthermore, the same clone had a higher alcohol content (13.97±0.03%) in each year of the study, which indicated that it ripened faster than other clones (13.06-13.08 %) and compared to the standard (13.04±0.07%). This finding suggested that the clone No. 010 could possibly have a significant economic impact and further increase popularity of Cabernet Franc in a cooler climate viticultural region. It was also found to have the highest contents of aldehydes (488±1.54 mg/L) and esters (322±0.71 mg/L) compared to aldehydes (452-467 mg/L) and

  16. Chemical composition and spasmolytic activity of Cymbopogon schoenanthus (L. Spreng. (Poaceae essential oil from Sudan

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    Pavlović Ivan

    2017-01-01

    Full Text Available The plants of genus Cymbopogon are well known for their use in traditional medicine and for their high content of essential oils that are widely used as flavoring agents, fragrances, cosmetics, and pharmaceuticals. Essential oils isolated from the dried stems and inflorescence of cultivated Cymbopogon schoenanthus (L. Spreng. (Poaceae collected from Khartoum state (Sudan in two periods were studied. The results of chemical analysis of C. schoenanthus revealed that this plant is rich in essential oil which is a valuable source of the commercially important monoterpene, piperitone (47.7-71.5%. Other abundant constituents of the oils were intermedeol (6.1-17.3%, δ-2-carene (4.5-10.0% and elemol (2.7-9.0%. The essential oil from the inflorescence was tested for spasmolytic activity using three different experimental models: against spontaneous contractions, contractions induced with acetylcholine and contractions induced with potassium chloride. The oil exhibited strong, significant and dose-dependent spasmolytic activity, indicating the possibility for further investigations of this essential oil for its medicinal purposes or application in food industry. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no.173021 and Grant no. III41018

  17. Chemical structure and antioxidant activity of a new exopolysaccharide produced from Micrococcus luteus

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    Mohsen Mohamed Selim Asker

    2014-12-01

    Full Text Available An exopolysaccharide (EPS reaching a maximum of 13 g/L was isolated from Micrococcus luteus by ethanol precipitation. The crude EPS was purified by chromatography on DEAE-cellulose and Sephacryl S-200, affording a polysaccharide active fraction (AEP with a molecular weight of ∼137 kDa. AEP was investigated by a combination of chemical and chromatographic methods including FTIR, HPLC, periodate oxidation, methylation and GC–MS. Data obtained indicated that AEP was composed of mannose, arabinose, glucose and glucuronic acid in a molar ratio of 3.6:2.7:2.1:1.0, respectively. The main backbone consists of mannose units linked with (1→6-glycosidic bonds and arabinose units linked with (1→5-glycosidic bonds. There is a side chain consisting of mannose units linked with (1→6-glycosidic bonds at C3, when all glucose and most of glucuronic acid are found in the side chain. The in vitro antioxidant assay showed that AEP possesses DPPH radical-scavenging activity, with an EC50 value of 180 μg/mL.

  18. Antioxidant Activities and Chemical Constituents of Flavonoids from the Flower of Paeonia ostii.

    Science.gov (United States)

    Zhang, Huifang; Li, Xiaofang; Wu, Ke; Wang, Mengke; Liu, Pu; Wang, Xinsheng; Deng, Ruixue

    2016-12-23

    Paeonia ostii is a traditional medicinal plant popularly used in China. This study intended to evaluate the antioxidant properties and the chemical components of the flavonoid-rich extracts from the flowers of P. ostii . The results showed that the flavonoid-rich extracts from the flowers of P. ostii had strong scavenging capacities on 2,2'-Azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS), hydroxyls, superoxide anions, and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals in a dose-dependent manner. Five flavonoids, dihydrokaempferol ( 1 ), apigenin-7- O -β-d-glucoside ( 2 ), apigenin-7- O -β-d-neohesperidoside ( 3 ), kaempferol-7- O -β-d-glucopyranoside ( 4 ), and kaempferol-3- O -β-d-glucopyranosyl-7- O -β-d-glucopyranoside ( 5 ), were isolated from the flavonoid-rich extracts of the flowers of P. ostii . High-performance liquid chromatography (HPLC) analysis revealed that compounds 3 and 4 were abundant in the P. ostii flower and in flavonoid-rich extracts. The main components of the flower of P. ostii are flavonoids. The high antioxidant activity of the flavonoid-rich extracts may be attributed to the high content of flavonoids. The five isolated flavonoids were the primary antioxidant ingredients, and may play important roles in the strong antioxidant activities of this flower. Based on the obtained results, the flower of P. ostii could be a potential source of natural antioxidants in food and pharmaceutical applications.

  19. Chemical constituents and antioxidant activity of the essential oil from leaves of Annona vepretorum Mart. (Annonaceae).

    Science.gov (United States)

    Araújo, Camila de Souza; de Oliveira, Ana Paula; Lima, Rafaely Nascimento; Alves, Péricles Barreto; Diniz, Tâmara Coimbra; da Silva Almeida, Jackson Roberto Guedes

    2015-01-01

    Annona vepretorum (AV) is a native tree from Caatinga biome (semiarid region of Brazil) popularly known as "araticum" and "pinha da Caatinga." This study was carried out to evaluate the chemical constituents and antioxidant activity (AA) of the essential oil from the leaves from AV (EO-Av) collected in Petrolina, Pernambuco, Brazil. Fresh leaves of AV were cut into pieces, and subjected to distillation for 2 h in a clevenger-type apparatus. Gas chromatograph (GC) analyses were performed using a mass spectrometry/flame ionization detector. The identification of the constituents was assigned on the basis of comparison of their relative retention indices. The antioxidant ability of the EO was investigated through two in vitro models such as radical scavenging activity using 2,2-diphenyl-1-picrylhydrazyl method and β-carotene-linoleate-model system. The positive controls (ascorbic acid, butylated hydroxyanisole and butylated hydroxytoluene) were those using the standard solutions. Assays were carried out in triplicate. The oil showed a total of 21 components, and 17 were identified, representing 93.9% of the crude EO. Spathulenol (43.7%), limonene (20.5%), caryophyllene oxide (8.1%) and α-pinene (5.5%) were found to be the major individual constituents. Spathulenol and caryophyllene oxide could be considered chemotaxonomic markers of these genera. The EO demonstrated weak AA.

  20. Preparation and photocatalytic activity of chemically-bonded phosphate ceramics containing TiO2

    Science.gov (United States)

    Martins, Monize Aparecida; de Lima, Bruna de Oliveira; Ferreira, Leticia Patrício; Colonetti, Emerson; Feltrin, Jucilene; De Noni, Agenor

    2017-05-01

    Titanium dioxide was incorporated into chemically-bonded phosphate ceramic for use as photocatalytic inorganic coating. The coatings obtained were applied to unglazed ceramic tiles and cured at 350 °C. The surfaces were characterized by photocatalytic activity, determined in aqueous medium, based on the degradation of methylene blue dye. The effects of the percentage of TiO2 and the thickness of the layer on the photocatalytic efficiency were evaluated. The influence of the incorporation of TiO2 on the consolidation of the phosphate matrix coating was investigated using the wear resistance test. The crystalline phases of the coatings obtained were determined by XRD. The microstructure of the surfaces was analyzed by SEM. The thermal curing treatment did not cause a phase transition from anatase to rutile. An increase in the photocatalytic activity of the coating was observed with an increase in the TiO2 content. The dye degradation indices ranged from 14.9 to 44.0%. The photocatalytic efficiency was not correlated with the thickness of the coating layer deposited. The resistance to wear decreased with an increase in the TiO2 content. Comparison with a commercial photocatalytic ceramic coating indicated that there is a range of values for the TiO2 contents which offer potential for photocatalytic applications.

  1. Coriandrum sativum and Lavandula angustifolia Essential Oils: Chemical Composition and Activity on Central Nervous System.

    Science.gov (United States)

    Caputo, Lucia; Souza, Lucéia Fátima; Alloisio, Susanna; Cornara, Laura; De Feo, Vincenzo

    2016-11-30

    The aims of this study are to determine the chemical composition of Lavandula angustifolia Mill. and Coriandrum sativum L. essential oils, to evaluate their cytotoxic effects in SH-SY5Y human neuroblastoma cells, to investigate whether an alteration of adenylate cyclase 1 (ADCY1) and of extracellular signal-regulated kinase (ERK) expression can take part in the molecular mechanisms of the essential oils, and to study their possible neuronal electrophysiological effects. The essential oils were obtained by hydrodistillation, and studied by GC and GC-MS. In the oils from L. angustifolia and C. sativum , linalool was the main component (33.1% and 67.8%, respectively). SH-SY5Y cells were incubated with different concentrations of essential oils and of linalool. Cell viability and effects on ADCY1 and ERK expression were analyzed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide MTT and Western blotting, respectively. Variation in cellular electrophysiology was studied in primary cultures of rat cortical neurons with a multi-electrode array (MEA)-based approach. The essential oils and linalool revealed different cytotoxic activities. Linalool inhibited ADCY1 and ERK expression. Neuronal networks subjected to L. angustifolia and C. sativum essential oils showed a concentration-dependent inhibition of spontaneous electrical activity.

  2. Chemical Tools of Octopus maya during Crab Predation Are Also Active on Conspecifics.

    Science.gov (United States)

    Pech-Puch, Dawrin; Cruz-López, Honorio; Canche-Ek, Cindy; Campos-Espinosa, Gabriela; García, Elpidio; Mascaro, Maite; Rosas, Carlos; Chávez-Velasco, Daniel; Rodríguez-Morales, Sergio

    2016-01-01

    Octopus maya is a major socio-economic resource from the Yucatán Peninsula in Mexico. In this study we report for the first time the chemical composition of the saliva of O. maya and its effect on natural prey, i.e. the blue crab (Callinectes sapidus), the crown conch snail (Melongena corona bispinosa), as well as conspecifics. Salivary posterior glands were collected from octopus caught by local fishers and extracted with water; this extract paralyzed and predigested crabs when it was injected into the third pereiopod. The water extract was fractionated by membrane ultrafiltration with a molecular weight cut-off of 3 kDa leading to a metabolic phase (>3 kDa) and a neurotoxic fraction (octopus saliva might be used among conspecifics for defense and for reduction of competition. Bioguided separation of the neurotoxic fraction by chromatography led to a paralysis fraction and a relaxing fraction. The paralyzing activity of the saliva was exerted by amino acids, while the relaxing activity was due to the presence of serotonin. Prey-handling studies revealed that O. maya punctures the eye or arthrodial membrane when predating blue crabs and uses the radula to bore through crown conch shells; these differing strategies may help O. maya to reduce the time needed to handle its prey.

  3. Kinetics and physico-chemical properties of alkali activated blast-furnace slag/basalt pastes

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    H. El Didamony

    2012-12-01

    Full Text Available Granulated blast-furnace slag (GBFS is a by-product of the metallurgical industry and consists mainly of lime and calcium–magnesium aluminosilicates that defined as the glassy granular material formed by rapid cooling of molten slag with excess water resulting in an amorphous structure. Alkali-activated slag (AAS binders have taken a great interest from researchers due to its manufacturing process which has important benefits from the point of view of the lower energy requirements and lower emission of greenhouse gases with respect to the manufacturing of Portland cement. In this study, GBFS was replaced by 20, 40 and 60 wt.% of basalt activated by 6 wt.% of alkali mixture composed of 1:1 sodium hydroxide (SH and liquid sodium silicate (LSS mixed with sea water and cured in 100% relative humidity up to 90 days. The physic-chemical parameters were studied by determination of setting time, combined water content, bulk density and compressive strength. As the amount of basalt increases the setting time as well as compressive strength decreases while the bulk density increases. The compressive strength values of dried pastes are greater than those of saturated pastes. The hydrated products are identified by TGA/DTG analysis, IR spectroscopy and scanning electron microscopy (SEM.

  4. Detailed solvent, structural, quantum chemical study and antimicrobial activity of isatin Schiff base

    Science.gov (United States)

    Brkić, Dominik R.; Božić, Aleksandra R.; Marinković, Aleksandar D.; Milčić, Miloš K.; Prlainović, Nevena Ž.; Assaleh, Fathi H.; Cvijetić, Ilija N.; Nikolić, Jasmina B.; Drmanić, Saša Ž.

    2018-05-01

    The ratios of E/Z isomers of sixteen synthesized 1,3-dihydro-3-(substituted phenylimino)-2H-indol-2-one were studied using experimental and theoretical methodology. Linear solvation energy relationships (LSER) rationalized solvent influence of the solvent-solute interactions on the UV-Vis absorption maxima shifts (νmax) of both geometrical isomers using the Kamlet-Taft equation. Linear free energy relationships (LFER) in the form of single substituent parameter equation (SSP) was used to analyze substituent effect on pKa, NMR chemical shifts and νmax values. Electron charge density was obtained by the use of Quantum Theory of Atoms in Molecules, i.e. Bader's analysis. The substituent and solvent effect on intramolecular charge transfer (ICT) were interpreted with the aid of time-dependent density functional (TD-DFT) method. Additionally, the results of TD-DFT calculations quantified the efficiency of ICT from the calculated charge-transfer distance (DCT) and amount of transferred charge (QCT). The antimicrobial activity was evaluated using broth microdilution method. 3D QSAR modeling was used to demonstrate the influence of substituents effect as well as molecule geometry on antimicrobial activity.

  5. Chemical composition and antimicrobial activity of essential oil from cones of Pinus koraiensis.

    Science.gov (United States)

    Lee, Jeong-Ho; Yang, Hye-Young; Lee, Hong-Sub; Hong, Soon-Kwang

    2008-03-01

    The essential oil from the cones of Pinus koraiensis was prepared after removing the seeds, and its chemical composition analyzed using gas chromatography-mass spectrometry (GC-MS). Hydrodistillation of the P. koraiensis cones yielded 1.07% (v/w) of essential oil, which was almost three times the amount of essential oil extracted from the needles of the same plant. Moreover, the antimicrobial activities of the oil against the growth of Gram-positive bacteria, Gram-negative bacteria, and fungi were evaluated using the agar disc diffusion method and broth microdilution method. Eighty-seven components, comprising about 96.8% of the total oil, were identified. The most abundant oil components were limonene (27.90%), alpha-pinene (23.89%), beta-pinene (12.02%), 3-carene (4.95%), beta-myrcene (4.53%), isolongifolene (3.35%), (-)-bornyl acetate (2.02%), caryophyllene (1.71%), and camphene (1.54%). The essential oil was confirmed to have significant antimicrobial activities, especially against pathogenic fungal strains such as Candida glabrata YFCC 062 and Cryptococcus neoformans B 42419. Therefore, the present results indicate that the essential oil from the cones of Pinus koraiensis can be used in various ways as a nontoxic and environmentally friendly disinfectant.

  6. Chemical composition of Schinus molle essential oil and its cytotoxic activity on tumour cell lines.

    Science.gov (United States)

    Díaz, Cecilia; Quesada, Silvia; Brenes, Oscar; Aguilar, Gilda; Cicció, José F

    2008-01-01

    The leaf essential oil hydrodistilled from Schinus molle grown in Costa Rica was characterised in terms of its chemical composition, antioxidant activity, ability to induce cytotoxicity and the mechanism of cell death involved in the process. As a result, 42 constituents, accounting for 97.2% of the total oil, were identified. The major constituents of the oil were beta-pinene and alpha-pinene. The antioxidant activity showed an IC(50) of 36.3 microg mL(-1). The essential oil was cytotoxic in several cell lines, showing that it is more effective on breast carcinoma and leukemic cell lines. The LD(50) for cytotoxicity at 48 h in K562 corresponded to 78.7 microg mL(-1), which was very similar to the LD(50) obtained when apoptosis was measured. The essential oil did not induce significant necrosis up to 200 microg mL(-1), which together with the former results indicate that apoptosis is the main mechanism of toxicity induced by S. molle essential oil in this cell line. In conclusion, the essential oil tested was weak antioxidant and induced cytotoxicity in different cell types by a mechanism related to apoptosis. It would be interesting to elucidate the role that different components of the oil play in the effect observed here, since some of them could have potential anti-tumoural effects, either alone or in combination.

  7. Chemical Composition, Larvicidal and Cytotoxic Activities of the Essential Oils from two Bauhinia Species

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    Leôncio M. de Sousa

    2016-05-01

    Full Text Available The essential oils obtained by hydrodistilation from leaves of Bauhinia pulchella Benth. and Bauhinia ungulata L. were analysed by GC-FID and GC-MS. The major components of B. pulchella essential oil were identified as a -pinene (23.9%, caryophyllene oxide (22.4% and b -pinene (12.2%, while in the B. ungulata essential oil were caryophyllene oxide (23.0%, (E-caryophyllene (14.5% and a -copaene (7.2%. The essential oils were subsequently evaluated for their larvicidal and cytotoxic activities. Larval bioassay against Aedes aegypti of B. pulchella and B. ungulata essential oils showed LC 50 values of 105.9 ± 1.5 and 75.1 ± 2.8 m g/mL, respectively. The essential oils were evaluated against four human cancer cells lines: HL-60 (pro-myelocytic leukemia, MCF-7 (breast adenocarcinoma, NCI-H292 (lung carcinoma and HEP-2 ( cervical adenocarcinoma, showing IC 50 values in the range of 9.9 to 53.1 m g/mL. This is the first report on chemical composition of essential from leaves of B. pulchella and on larvicidal and cytotoxic activities of the essential oils.

  8. Chemical composition and biological activities of Tunisian Cupressus arizonica Greene essential oils.

    Science.gov (United States)

    Ismail, Amri; Mancini, Emilia; De Martino, Laura; Hamrouni, Lamia; Hanana, Mohsen; Jamoussi, Bassem; Gargouri, Samia; Scognamiglio, Mariarosa; De Feo, Vincenzo

    2014-01-01

    The chemical composition of the essential oils obtained by hydrodistillation of leaves, stems, and female cones of Cupressus arizonica Greene, grown in Tunisia, was studied by GC-FID and GC/MS analyses. Altogether, 62 compounds were identified, 62 in the leaf oil, 19 in the cone oil, and 24 in the stem oil. The cone and stem oils were mainly composed by monoterpene hydrocarbons (96.6 and 85.2%, resp.). In the leaf oil, the total sesquiterpene fraction constituted 36.1% and that of the monoterpene hydrocarbons 33.8% of the total oil composition. The three oils were evaluated for their in vitro herbicidal activity by determining their influence on the germination and the shoot and root growth of the four weed species Sinapis arvensis L., Lolium rigidum Gaudin, Trifolium campestre Schreb., and Phalaris canariensis L. At the highest doses tested (0.8 and 1.0 mg/ml), the leaf essential oil inhibited either totally or almost completely the seed germination and the shoot and root growth of S. arvensis and T. campestre. The oils were also tested for their antifungal activity; however, their effects on the fungal growth were statistically not significant. Copyright © 2014 Verlag Helvetica Chimica Acta AG, Zürich.

  9. Chemical Composition and Biological Activities of the Essential Oils from Three Melaleuca Species Grown in Tunisia

    Directory of Open Access Journals (Sweden)

    Ismail Amri

    2012-12-01

    Full Text Available The chemical composition of the essential oils of Melaleuca armillaris Sm., Melaleuca styphelioides Sm. and Melaleuca acuminata F. Muell., collected in Tunisia, was studied by means of GC and GC-MS analysis. In all, 46 compounds were identified, 38 for M. armillaris, 20 for M. acuminata and eight for M. styphelioides, respectively. The presence of a sesquiterpenic fraction (52.2% characterized the oil from M. armillaris; M. sthypheliodes oil was rich in methyl eugenol, a phenolic compound (91.1%, while M. acuminata oil is mainly constituted by oxygenated monoterpenoids (95.6%. The essential oils were evaluated for their in vitro potentially phytotoxic activity against germination and initial radicle growth of Raphanus sativus L., Lepidium sativum L., Sinapis arvensis L., Triticum durum L. and Phalaris canariensis L. seeds. The radicle elongation of five seeds was inhibited at the highest doses tested, while germination of all seeds was not affected. Moreover, the essential oils showed low antimicrobial activity against eight selected microorganisms.

  10. Chemical composition and biological activities of the essential oils from three Melaleuca species grown in Tunisia.

    Science.gov (United States)

    Amri, Ismail; Mancini, Emilia; De Martino, Laura; Marandino, Aurelio; Lamia, Hamrouni; Mohsen, Hanana; Bassem, Jamoussi; Scognamiglio, Mariarosa; Reverchon, Ernesto; De Feo, Vincenzo

    2012-12-05

    The chemical composition of the essential oils of Melaleuca armillaris Sm., Melaleuca styphelioides Sm. and Melaleuca acuminata F. Muell., collected in Tunisia, was studied by means of GC and GC-MS analysis. In all, 46 compounds were identified, 38 for M. armillaris, 20 for M. acuminata and eight for M. styphelioides, respectively. The presence of a sesquiterpenic fraction (52.2%) characterized the oil from M. armillaris; M. sthypheliodes oil was rich in methyl eugenol, a phenolic compound (91.1%), while M. acuminata oil is mainly constituted by oxygenated monoterpenoids (95.6%). The essential oils were evaluated for their in vitro potentially phytotoxic activity against germination and initial radicle growth of Raphanus sativus L., Lepidium sativum L., Sinapis arvensis L., Triticum durum L. and Phalaris canariensis L. seeds. The radicle elongation of five seeds was inhibited at the highest doses tested, while germination of all seeds was not affected. Moreover, the essential oils showed low antimicrobial activity against eight selected microorganisms.

  11. Antimicrobial Activity and Chemical Composition of Essential Oils from Verbenaceae Species Growing in South America

    Directory of Open Access Journals (Sweden)

    Cristina M. Pérez Zamora

    2018-03-01

    Full Text Available The Verbenaceae family includes 2600 species grouped into 100 genera with a pantropical distribution. Many of them are important elements of the floras of warm-temperature and tropical regions of America. This family is known in folk medicine, and its species are used as digestive, carminative, antipyretic, antitussive, antiseptic, and healing agents. This review aims to collect information about the essential oils from the most reported species of the Verbenaceae family growing in South America, focusing on their chemical composition, antimicrobial activity, and synergism with commercial antimicrobials. The information gathered comprises the last twenty years of research within the South American region and is summarized taking into consideration the most representative species in terms of their essential oils. These species belong to Aloysia, Lantana, Lippia, Phyla, and Stachytarpheta genera, and the main essential oils they contain are monoterpenes and sesquiterpenes, such as β-caryophyllene, thymol, citral, 1,8-cineole, carvone, and limonene. These compounds have been found to possess antimicrobial activities. The synergism of these essential oils with antibiotics is being studied by several research groups. It constitutes a resource of interest for the potential use of combinations of essential oils and antibiotics in infection treatments.

  12. Chemical study of sediments from Solimoes and Negro rivers by Instrumental Neutron Activation Analysis (INAA)

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Jose O. dos [Coordenacao de Cursos Tecnicos e Superiores. Instituto Federal de Educacao, Ciencia e Tecnologia de Sergipe, Lagarto, SE (Brazil); Munita, Casimiro S., E-mail: camunita@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Soares, Emilio A.A., E-mail: easores@ufam.edu.br [Departamento de Geociencias. Universidade Federal do Amazonas (UFAM), Manaus, AM (Brazil)

    2011-07-01

    The events of the last 70,000 yrs of the history of the Solimoes-Amazon river system are recorded in the fluvial terraces at region of confluence of the Negro and Solimoes rivers, and are markers of changes in the landscape of the Amazon region and it can be observed by analyzing the sedimentary deposits quaternary in Amazon fluvial system. The aim of this work was to contribute with the characterization sedimentological - stratigraphic of Pleistocene succession of the confluence zone of the Negro and Solimoes rivers by means of elemental chemical analysis. To provenance study, 24 elements were determined by Instrumental Neutron Activation Analysis from sediment samples collected at confluence of Negro and Solimoes rivers and the results were interpreted using cluster and linear discriminant analysis, which classification to priori were samples previously defined according to Pleistocene stratigraphic units individualized at study area. According to discriminant analysis, one can infer that samples from the basin of the Solimoes River and Parana do Ariau grabens (GPA) are not significantly different, but there was a clear separation of sediments from Negro and GPA groups. It was also obtained that samples from highest and lowest terraces that the of the Solimoes river and Parana do Ariau are different, suggesting that it is a process that reflects the influence of chemical weathering on the uppermost terrace deposits. Thus, this work contributes to determine the contribution of the sediments deposited by the Solimoes and Negro rivers in the filling of tectonic depressions and in the variations of degree of weathering between younger and older units, and provides additional subsidies to build the geological evolution of the area. (author)

  13. Capturing ecology in modeling approaches applied to environmental risk assessment of endocrine active chemicals in fish.

    Science.gov (United States)

    Mintram, Kate S; Brown, A Ross; Maynard, Samuel K; Thorbek, Pernille; Tyler, Charles R

    2018-02-01

    Endocrine active chemicals (EACs) are widespread in freshwater environments and both laboratory and field based studies have shown reproductive effects in fish at environmentally relevant exposures. Environmental risk assessment (ERA) seeks to protect wildlife populations and prospective assessments rely on extrapolation from individual-level effects established for laboratory fish species to populations of wild fish using arbitrary safety factors. Population susceptibility to chemical effects, however, depends on exposure risk, physiological susceptibility, and population resilience, each of which can differ widely between fish species. Population models have significant potential to address these shortfalls and to include individual variability relating to life-history traits, demographic and density-dependent vital rates, and behaviors which arise from inter-organism and organism-environment interactions. Confidence in population models has recently resulted in the EU Commission stating that results derived from reliable models may be considered when assessing the relevance of adverse effects of EACs at the population level. This review critically assesses the potential risks posed by EACs for fish populations, considers the ecological factors influencing these risks and explores the benefits and challenges of applying population modeling (including individual-based modeling) in ERA for EACs in fish. We conclude that population modeling offers a way forward for incorporating greater environmental relevance in assessing the risks of EACs for fishes and for identifying key risk factors through sensitivity analysis. Individual-based models (IBMs) allow for the incorporation of physiological and behavioral endpoints relevant to EAC exposure effects, thus capturing both direct and indirect population-level effects.

  14. Phytotoxic activity and chemical composition of aqueous volatile fractions from Eucalyptus species.

    Directory of Open Access Journals (Sweden)

    Jinbiao Zhang

    Full Text Available The essential oils from four Eucalyptus species (E. spathulata, E. salubris, E. brockwayii and E. dundasii have been previously confirmed to have stronger inhibitory effects on germination and seedling growth of silverleaf nightshade (Solanum elaeagnifolium Cav.. The aqueous volatile fractions (AVFs were the water soluble volatile fractions produced together with the essential oils (water insoluble fractions during the steam distillation process. The aim of this study was to further assess the phytotoxicity of AVFs from the four Eucalyptus species and their chemical composition. The fresh leaves of the four Eucalyptus species were used for the extraction of AVFs. The AVFs were tested for their phytotoxic effects on the perennial weed, silverleaf nightshade under laboratory conditions. The chemical compositions of the AVFs were determined by gas chromatograph-mass spectrometry (GC-MS. Our results showed that the AVFs had strong inhibition on the germination and seedling growth of silverleaf nightshade. The inhibition index increased with the increasing concentrations of AVFs. The inhibitory effects of the AVFs varied between different Eucalyptus species. The AVF from E. salubris demonstrated the highest inhibitory activity on the weed tested, with complete inhibition on germination and seedling growth at a concentration of 75%. The GC-MS analysis revealed that 1,8-cineole, isopentyl isovalerate, isomenthol, pinocarvone, trans-pinocarveol, alpha-terpineol and globulol were the main compounds in the AVFs. These results indicated that all AVFs tested had differential inhibition on the germination and seedling growth of silverleaf nightshade, which could be due to the joint effects of compounds present in the AVFs as these compounds were present in different quantities and ratio between Eucalyptus species.

  15. Chemical Inhibition of Histone Deacetylases 1 and 2 Induces Fetal Hemoglobin through Activation of GATA2.

    Directory of Open Access Journals (Sweden)

    Jeffrey R Shearstone

    Full Text Available Therapeutic intervention aimed at reactivation of fetal hemoglobin protein (HbF is a promising approach for ameliorating sickle cell disease (SCD and β-thalassemia. Previous studies showed genetic knockdown of histone deacetylase (HDAC 1 or 2 is sufficient to induce HbF. Here we show that ACY-957, a selective chemical inhibitor of HDAC1 and 2 (HDAC1/2, elicits a dose and time dependent induction of γ-globin mRNA (HBG and HbF in cultured primary cells derived from healthy individuals and sickle cell patients. Gene expression profiling of erythroid progenitors treated with ACY-957 identified global changes in gene expression that were significantly enriched in genes previously shown to be affected by HDAC1 or 2 knockdown. These genes included GATA2, which was induced greater than 3-fold. Lentiviral overexpression of GATA2 in primary erythroid progenitors increased HBG, and reduced adult β-globin mRNA (HBB. Furthermore, knockdown of GATA2 attenuated HBG induction by ACY-957. Chromatin immunoprecipitation and sequencing (ChIP-Seq of primary erythroid progenitors demonstrated that HDAC1 and 2 occupancy was highly correlated throughout the GATA2 locus and that HDAC1/2 inhibition led to elevated histone acetylation at well-known GATA2 autoregulatory regions. The GATA2 protein itself also showed increased binding at these regions in response to ACY-957 treatment. These data show that chemical inhibition of HDAC1/2 induces HBG and suggest that this effect is mediated, at least in part, by histone acetylation-induced activation of the GATA2 gene.

  16. Phytotoxic Activity and Chemical Composition of Aqueous Volatile Fractions from Eucalyptus Species

    Science.gov (United States)

    Zhang, Jinbiao; An, Min; Wu, Hanwen; Liu, De Li; Stanton, Rex

    2014-01-01

    The essential oils from four Eucalyptus species (E. spathulata, E. salubris, E. brockwayii and E. dundasii) have been previously confirmed to have stronger inhibitory effects on germination and seedling growth of silverleaf nightshade (Solanum elaeagnifolium Cav.). The aqueous volatile fractions (AVFs) were the water soluble volatile fractions produced together with the essential oils (water insoluble fractions) during the steam distillation process. The aim of this study was to further assess the phytotoxicity of AVFs from the four Eucalyptus species and their chemical composition. The fresh leaves of the four Eucalyptus species were used for the extraction of AVFs. The AVFs were tested for their phytotoxic effects on the perennial weed, silverleaf nightshade under laboratory conditions. The chemical compositions of the AVFs were determined by gas chromatograph–mass spectrometry (GC-MS). Our results showed that the AVFs had strong inhibition on the germination and seedling growth of silverleaf nightshade. The inhibition index increased with the increasing concentrations of AVFs. The inhibitory effects of the AVFs varied between different Eucalyptus species. The AVF from E. salubris demonstrated the highest inhibitory activity on the weed tested, with complete inhibition on germination and seedling growth at a concentration of 75%. The GC-MS analysis revealed that 1,8-cineole, isopentyl isovalerate, isomenthol, pinocarvone, trans-pinocarveol, alpha-terpineol and globulol were the main compounds in the AVFs. These results indicated that all AVFs tested had differential inhibition on the germination and seedling growth of silverleaf nightshade, which could be due to the joint effects of compounds present in the AVFs as these compounds were present in different quantities and ratio between Eucalyptus species. PMID:24681490

  17. Chemical study of sediments from Solimoes and Negro rivers by Instrumental Neutron Activation Analysis (INAA)

    International Nuclear Information System (INIS)

    Santos, Jose O. dos; Munita, Casimiro S.; Soares, Emilio A.A.

    2011-01-01

    The events of the last 70,000 yrs of the history of the Solimoes-Amazon river system are recorded in the fluvial terraces at region of confluence of the Negro and Solimoes rivers, and are markers of changes in the landscape of the Amazon region and it can be observed by analyzing the sedimentary deposits quaternary in Amazon fluvial system. The aim of this work was to contribute with the characterization sedimentological - stratigraphic of Pleistocene succession of the confluence zone of the Negro and Solimoes rivers by means of elemental chemical analysis. To provenance study, 24 elements were determined by Instrumental Neutron Activation Analysis from sediment samples collected at confluence of Negro and Solimoes rivers and the results were interpreted using cluster and linear discriminant analysis, which classification to priori were samples previously defined according to Pleistocene stratigraphic units individualized at study area. According to discriminant analysis, one can infer that samples from the basin of the Solimoes River and Parana do Ariau grabens (GPA) are not significantly different, but there was a clear separation of sediments from Negro and GPA groups. It was also obtained that samples from highest and lowest terraces that the of the Solimoes river and Parana do Ariau are different, suggesting that it is a process that reflects the influence of chemical weathering on the uppermost terrace deposits. Thus, this work contributes to determine the contribution of the sediments deposited by the Solimoes and Negro rivers in the filling of tectonic depressions and in the variations of degree of weathering between younger and older units, and provides additional subsidies to build the geological evolution of the area. (author)

  18. Insecticidal Activity and Chemical Composition of the Morinda lucida Essential Oil against Pulse Beetle Callosobruchus maculatus

    Directory of Open Access Journals (Sweden)

    Moses S. Owolabi

    2014-01-01

    Full Text Available Insecticidal activity of essential oil extracted from Morinda lucida was tested on pulse beetle Callosobruchus maculatus, which is a pest that causes serious damage to several pulses. The insecticidal activity was compared with two pesticides, Phostoxin and Primo-ban-20. 120 mixed sex adult C. maculatus were introduced, along with 30 g of cowpeas. Four concentrations (0.40, 0.20, 0.10, and 0.05 μg/mL of the M. lucida essential oil, Phostoxin, and Primo-ban-20 were tested. Essential oil chemical composition was analyzed by GC-MS. M. lucida essential oil showed a high toxicological effect, producing 100% mortality after 72 hours at a dose of 0.20 μg/mL. M. lucida essential oil had a potent insecticidal activity (LC90 = 0.629 μg/mL compared to both pesticides, Phostoxin (LC90 = 0.652 μg/mL and Primo-ban-20 (LC90 = 0.726 μg/mL, at 24 h. The main compounds of the essential oil were the oxygenated monoterpenoids, 1,8-cineole (43.4%, and α-terpinyl acetate (14.5%, and the monoterpene hydrocarbons, mostly sabinene (8.2% and β-pinene (4.0%. Results clearly indicate that M. lucida essential oil can be used as an effective alternative for pulse beetle C. maculatus control, and it could be tested against other pulse beetles affecting Asia and Africa and throughout the world, thereby reducing use of synthetic pesticides.

  19. Chemical Constituents and Insecticidal Activities of Ajania fruticulosa Essential Oil.

    Science.gov (United States)

    Liang, Jun-Yu; Guo, Shan-Shan; You, Chun-Xue; Zhang, Wen-Juan; Wang, Cheng-Fang; Geng, Zhu-Feng; Deng, Zhi-Wei; Du, Shu-Shan; Zhang, Ji

    2016-08-01

    The insecticidal activity and chemical constituents of the essential oil from Ajania fruticulosa were investigated. Twelve constituents representing 91.0% of the essential oil were identified, and the main constituents were 1,8-cineole (41.40%), (+)-camphor (32.10%), and myrtenol (8.15%). The essential oil exhibited contact toxicity against Tribolium castaneum and Liposcelis bostrychophila adults with LD50 values of 105.67 μg/adult and 89.85 μg/cm(2) , respectively. The essential oil also showed fumigant toxicity against two species of insect with LC50 values of 11.52 and 0.65 mg/l, respectively. 1,8-Cineole exhibited excellent fumigant toxicity (LC50  = 5.47 mg/l) against T. castaneum. (+)-Camphor showed obvious fumigant toxicity (LC50  = 0.43 mg/l) against L. bostrychophila. Myrtenol showed contact toxicity (LD50  = 29.40 μg/cm(2) ) and fumigant toxicity (LC50  = 0.50 mg/l) against L. bostrychophila. 1,8-Cineole and (+)-camphor showed strong insecticidal activity to some important insects, and they are main constituents of A. fruticulosa essential oil. The two compounds may be related to insecticidal activity of A. fruticulosa essential oil against T. castaneum and L. bostrychophila. © 2016 Wiley-VHCA AG, Zürich.

  20. Chemical composition and cytotoxicity activity of the essential oil of Pterodon emarginatus

    Directory of Open Access Journals (Sweden)

    Rafael C. Dutra

    2012-10-01

    Full Text Available Pterodon emarginatus Vogel, Fabaceae, is a native aromatic tree distributed by central region of Brazil. Hydroalcoholic infusions of the seeds are used in folk medicine for their anti-rheumatic and anti-inflammatory properties. The objective of this work was identified the chemical components and verify the cytotoxic effect of the essential oil (EO from P. emarginatus seeds. Thus, the EO of P. emarginatus seeds was analyzed by GC/MS analysis followed by brine shrimp lethality test and cytotoxic activity against tumor cell lines and human peripheral mononuclear blood cells (PBMC. The cancer cell lines tested were C6 (rat glioma, MeWo (human melanoma, CT26.WT (mouse colon carcinoma, MDA (human breast cancer, A549 (human lung carcinoma, B16-F1 (mouse melanoma, CHO-K1 (hamster ovary cell and BHK-21 (hamster kidney fibroblast. Eleven compounds were identified by GC and CG/MS analyses. The main compounds with concentrations higher than 5% were β-elemene (15.3%, trans-caryophyllene (35.9%, α-humulene (6.8%, germacrene-D (9.8%, bicyclo germacrene (5.5% and spathulenol (5.9%. The EO of P. emarginatus seeds showed toxicity to Artemia salina (LC50 1.63 µg/mL and was active against all the cell lines tested. The potent cytotoxic activity had IC50 values ranging from 24.9 to 47 µg/mL. However, EO (1-100 µg/mL had less cytotoxicity in PBMCs isolated from a healthy subject. In summary, the present study showed the potential antiproliferative of the EO of P. emarginatus seeds.