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Sample records for activation chemical

  1. Active Chemical Sampling System for Underwater Chemical Source Localization

    Ryuichi Takemura; Hiromi Sakata; Hiroshi Ishida

    2016-01-01

    This paper investigates the effect of active water sampling to enhance chemical reception for small underwater robots. The search for a chemical source in a stagnant water environment is not an easy task because the chemical solution released from the source stays in the close vicinity of the source. No signal is obtained even if a robot with chemical sensors is placed a few centimeters from the chemical source. In the system under study, four electrochemical sensors are aligned in front of a...

  2. Linking algal growth inhibition to chemical activity

    Schmidt, Stine N.; Mayer, Philipp

    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 with the...

  3. Inorganic chemically active adsorbents (ICAAs)

    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.

  4. Activated coconut shell charcoal carbon using chemical-physical activation

    Budi, Esmar; Umiatin, Nasbey, Hadi; Bintoro, Ridho Akbar; Wulandari, Futri; Erlina

    2016-02-01

    The use of activated carbon from natural material such as coconut shell charcoal as metal absorbance of the wastewater is a new trend. The activation of coconut shell charcoal carbon by using chemical-physical activation has been investigated. Coconut shell was pyrolized in kiln at temperature about 75 - 150 °C for about 6 hours in producing charcoal. The charcoal as the sample was shieved into milimeter sized granule particle and chemically activated by immersing in various concentration of HCl, H3PO4, KOH and NaOH solutions. The samples then was physically activated using horizontal furnace at 400°C for 1 hours in argon gas environment with flow rate of 200 kg/m3. The surface morphology and carbon content of activated carbon were characterized by using SEM/EDS. The result shows that the pores of activated carbon are openned wider as the chemical activator concentration is increased due to an excessive chemical attack. However, the pores tend to be closed as further increasing in chemical activator concentration due to carbon collapsing.

  5. Chemical activation of molecules during coordination

    Activation processes of N2, O2, NO molecules in transition metal complexes and electron reconstructions of coordination sphere of compounds, related with it, were considered on tha basis of single-parameter approximation of vibronic activation theory. A special attention is paid to CO molecule activation in carbonyl complexes of transition metals (V, Nb, Mo, W, Tc, Re, Ru and others) and lanthanides. The effect of metal oxidation degree, the nature of metal and ligand, complex structure on chemical activation processes is analyzed

  6. Activity Therapy Services and Chemical Dependency Rehabilitation.

    James, Mark R.; Townsley, Robin K.

    1989-01-01

    Discusses how music, occupational, and recreation therapies can contribute to comprehensive treatment programs for chemical dependency. Sees prime contribution of activity therapy as lying in nature of experiential education, applying insight gained in counseling sessions and discussion groups to practical real-life situations. (Author/NB)

  7. Linking algal growth inhibition to chemical activity

    Schmidt, Stine N.; Mayer, Philipp

    2015-01-01

    Recently, high-quality data were published on the algal growth inhibition caused by 50 non-polar narcotic compounds, of which 39 were liquid compounds with defined water solubility. In the present study, the toxicity data for these liquids were applied to challenge the chemical activity range for...

  8. Service activities of chemical analysis division

    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)

  9. Collective Surfing of Chemically Active Particles

    Masoud, Hassan; Shelley, Michael J.

    2014-03-01

    We study theoretically the collective dynamics of immotile particles bound to a 2D surface atop a 3D fluid layer. These particles are chemically active and produce a chemical concentration field that creates surface-tension gradients along the surface. The resultant Marangoni stresses create flows that carry the particles, possibly concentrating them. For a 3D diffusion-dominated concentration field and Stokesian fluid we show that the surface dynamics of active particle density can be determined using nonlocal 2D surface operators. Remarkably, we also show that for both deep or shallow fluid layers this surface dynamics reduces to the 2D Keller-Segel model for the collective chemotactic aggregation of slime mold colonies. Mathematical analysis has established that the Keller-Segel model can yield finite-time, finite-mass concentration singularities. We show that such singular behavior occurs in our finite-depth system, and study the associated 3D flow structures.

  10. Antitumor activity of chemical modified natural compounds

    Marilda Meirelles de Oliveira

    1991-01-01

    Full Text Available Search of new activity substances starting from chemotherapeutic agents, continously appears in international literature. Perhaps this search has been done more frequently in the field of anti-tumor chemotherapy on account of the unsuccess in saving advanced stage patients. The new point in this matter during the last decade was computer aid in planning more rational drugs. In near future "the accessibility of supercomputers and emergence of computer net systems, willopen new avenues to rational drug design" (Portoghese, P. S. J. Med. Chem. 1989, 32, 1. Unknown pharmacological active compounds synthetized by plants can be found even without this eletronic devices, as tradicional medicine has pointed out in many contries, and give rise to a new drug. These compounds used as found in nature or after chemical modifications have produced successful experimental medicaments as FAA, "flavone acetic acid" with good results as inibitors of slow growing animal tumors currently in preclinical evaluation for human treatment. In this lecture some international contributions in the field of chemical modified compounds as antineoplasic drugs will be examined, particularly those done by Brazilian researches.

  11. Preparation of activated carbon by chemical activation under vacuum.

    Juan, Yang; Ke-Qiang, Qiu

    2009-05-01

    Activated carbons especially used for gaseous adsorption were prepared from Chinesefir sawdust by zinc chloride activation under vacuum condition. The micropore structure, adsorption properties, and surface morphology of activated carbons obtained under atmosphere and vacuum were investigated. The prepared activated carbons were characterized by SEM, FTIR, and nitrogen adsorption. It was found that the structure of the starting material is kept after activation. The activated carbon prepared under vacuum exhibited higher values of the BET surface area (up to 1079 m2 g(-1)) and total pore volume (up to 0.5665 cm3 g(-1)) than those of the activated carbon obtained under atmosphere. This was attributed to the effect of vacuum condition that reduces oxygen in the system and limits the secondary reaction of the organic vapor. The prepared activated carbon has well-developed microstructure and high microporosity. According to the data obtained, Chinese fir sawdust is a suitable precursor for activated carbon preparation. The obtained activated carbon could be used as a low-cost adsorbent with favorable surface properties. Compared with the traditional chemical activation, vacuum condition demands less energy consumption, simultaneity, and biomass-oil is collected in the procedure more conveniently. FTIR analysis showed that heat treatment would result in the aromatization of the carbon structure. PMID:19534162

  12. Foundational aspects of the concept of chemical activity

    Mayer, Philipp

    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 organisms and differences in chemical activity determine the direction and extent of diffusion between environmental compartments [1,2]. This makes chemical activity a meaningfull and well-defined exposure parameter that is closely linked to fugacity and freely dissolved concentration [2]. Classical...... toxicological studies have provided the first indication that narcosis occurs within a relatively narrow band of chemical activity [3-5], and during the last 10 years several studies have confirmed this for the „baseline toxicity“ of non-polar organic chemicals and their mixtures [6-8]. The first aim of this...

  13. Genus Mikania: chemical composition and phytotherapeutical activity

    Luciane C. Rufatto

    2012-12-01

    Full Text Available The genus Mikania ranks high in the list of best-selling natural products in the world. Its main distribution is in South America, but some species are found in Asia, North America and Africa. It is used for treating fever, rheumatism, colds and respiratory diseases, as well as snake bites and scorpion stings, due to its broad spectrum of action. There are approximately 430 species of this genus and only 12% have been studied, highlighting their chemical and pharmacological diversity. The main chemical groups are: coumarins and derivatives, sesquiterpenes, sesquiterpenes lactones, diterpenes, phytosterols/terpenoids and flavonoids. This review aims to supply useful references for scientists interested in natural products and the search for new compounds, from over the 300 already described for the genus.

  14. ILO activities in the area of chemical safety.

    Obadia, Isaac

    2003-08-21

    The ILO has been active in the area of safety in the use of chemicals at work since the year of its creation in 1919, including the development of international treaties and other technical instruments, the provision of technical assistance to its member States, and the development of chemical safety information systems. The two key ILO standards in this area are the Conventions on safety in the use of chemicals at work (No. 170, 1990), and the Prevention of Major Industrial Accidents (No. 174, 1993). The ILO Programme on occupational safety, health and environment (Safe Work) is currently responsible for ILO chemical safety activities. In the past two decades, most of ILO work in this area has been carried out within the context of inter-agency collaboration frameworks linking the ILO, WHO, UNEP, FAO, UNIDO, UNITAR, and the OECD, including the International Programme on Chemical Safety (IPCS), the Inter-Organisation Programme for the Sound Management of Chemicals (IOMC), and the Intergovernmental Forum on Chemical Safety (IFCS). Apart from the regular development, updating and dissemination of chemical safety information data bases such as the IPCS International Chemical Cards, the elaboration of a Globally harmonized system for the classification and labelling of Chemicals (GHS) has been the most outstanding achievement of this international collaboration on chemical safety. PMID:12909402

  15. Influence of process parameters on the surface and chemical properties of activated carbon obtained from biochar by chemical activation.

    Angın, Dilek; Altintig, Esra; Köse, Tijen Ennil

    2013-11-01

    Activated carbons were produced from biochar obtained through pyrolysis of safflower seed press cake by chemical activation with zinc chloride. The influences of process variables such as the activation temperature and the impregnation ratio on textural and chemical-surface properties of the activated carbons were investigated. Also, the adsorptive properties of activated carbons were tested using methylene blue dye as the targeted adsorbate. The experimental data indicated that the adsorption isotherms are well described by the Langmuir equilibrium isotherm equation. The optimum conditions resulted in activated carbon with a monolayer adsorption capacity of 128.21 mg g(-1) and carbon content 76.29%, while the BET surface area and total pore volume corresponded to 801.5m(2)g(-1) and 0.393 cm(3)g(-1), respectively. This study demonstrated that high surface area activated carbons can be prepared from the chemical activation of biochar with zinc chloride as activating agents. PMID:24080293

  16. Constructing Global Production Activity Indices: The Chemical Industry

    Saswati Mahapatra; Thomas K Swift

    2012-01-01

    This article first presents the challenges involved in constructing consistent, timely, and reliable short-term measures of national, regional, and global industry activity. The chemical industry is used as a case study. Second, this article presents the comparison of the movement or fluctuations in industrial production indices and chemical production indices that aid in determining if production in the chemical industry can be used as a proxy for total production in an economy. The American...

  17. Active Emulsions: Synchronization of Chemical Oscillators

    Fraden, Seth

    2012-02-01

    We explore the dynamical behavior of emulsions consisting of nanoliter volume droplets of the oscillatory Belousov-Zhabotinsky (BZ) reaction separated by a continuous oil phase. Some of the aqueous BZ reactants partition into the oil leading to chemical coupling of the drops. We use microfluidics to vary the size, composition and topology of the drops in 1D and 2D. Addition of a light sensitive catalyst to the drops and illumination with a computer projector allows each drop to be individually perturbed. A variety of synchronous regimes are found that systematically vary with the coupling strength and whether coupling is dominated by activatory or inhibitory species. In 1D we observe in- and anti-phase oscillations, stationary Turing patterns in which drops stop oscillating, but form spatially periodic patterns of drops in the oxidized and reduced states, and more complex combinations of stationary and oscillatory drops. In 2D, the attractors are more complex and vary with network topology and coupling strength. For hexagonal lattices as a function of increasing coupling strength we observe right and left handed rotating oscillations, mixed oscillatory and Turing states and finally full Turing states. Reaction -- diffusion models based on a simplified description of the BZ chemistry and diffusion of messenger species reproduce a number of the experimental results. For a range of parameters, a simplified phase oscillator model provides an intuitive understanding of the complex synchronization patterns. [4pt] ``Coupled oscillations in a 1D emulsion of Belousov--Zhabotinsky droplets,'' Jorge Delgado, Ning Li, Marcin Leda, Hector O. Gonzalez-Ochoa, Seth Fraden and Irving R. Epstein, Soft Matter, 7, 3155 (2011).

  18. Guiding catalytically active particles with chemically patterned surfaces

    Uspal, W E; Dietrich, S; Tasinkevych, M

    2016-01-01

    Catalytically active Janus particles suspended in solution create gradients in the chemical composition of the solution along their surfaces, as well as along any nearby container walls. The former leads to self-phoresis, while the latter gives rise to chemi-osmosis, providing an additional contribution to self-motility. Chemi-osmosis strongly depends on the molecular interactions between the diffusing chemical species and the wall. We show analytically, using an approximate "point-particle" approach, that by chemically patterning a planar substrate one can direct the motion of Janus particles: the induced chemi-osmotic flows can cause particles to either "dock" at the chemical step between the two materials, or to follow a chemical stripe. These theoretical predictions are confirmed by full numerical calculations. Generically, docking occurs for particles which tend to move away from their catalytic caps, while stripe-following occurs in the opposite case. Our analysis reveals the physical mechanisms governi...

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

    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.

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

    Kanniah Rajasekaran; Jian Chen; BECNEL, JAMES J.; Natasha M. Agramonte; Bernier, Ulrich R.; Maia Tsikolia; Kemal Husnu Can Baser; Betul Demirci; David E. Wedge; Nurhayat Tabanca; Sampson, Blair J.; Hamidou F. Sakhanokho; James M. Spiers

    2013-01-01

    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...

  1. Chemical and structural features influencing the biological activity of curcumin.

    Priyadarsini, K Indira

    2013-01-01

    Curcumin, a polyphenolic natural product, exhibits therapeutic activity against a number of diseases, attributed mainly to its chemical structure and unique physical, chemical, and biological properties. It is a diferuloyl methane molecule [1,7-bis (4-hydroxy-3- methoxyphenyl)-1,6-heptadiene-3,5-dione)] containing two ferulic acid residues joined by a methylene bridge. It has three important functionalities: an aromatic o-methoxy phenolic group, α, β-unsaturated β-diketo moiety and a seven carbon linker. Extensive research in the last two decades has provided evidence for the role of these different functional groups in its crucial biological activities. A few highlights of chemical structural features associated with the biological activity of curcumin are: The o-methoxyphenol group and methylenic hydrogen are responsible for the antioxidant activity of curcumin, and curcumin donates an electron/ hydrogen atom to reactive oxygen species. Curcumin interacts with a number of biomolecules through non-covalent and covalent binding. The hydrogen bonding and hydrophobicity of curcumin, arising from the aromatic and tautomeric structures along with the flexibility of the linker group are responsible for the non-covalent interactions. The α, β-unsaturated β-diketone moiety covalently interacts with protein thiols, through Michael reaction. The β-diketo group forms chelates with transition metals, there by reducing the metal induced toxicity and some of the metal complexes exhibit improved antioxidant activity as enzyme mimics. New analogues with improved activity are being developed with modifications on specific functional groups of curcumin. The physico-chemical and structural features associated with some of the biological activities of curcumin and important analogues are summarized in this article. PMID:23116315

  2. Structure activity relationships to assess new chemicals under TSCA

    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.

  3. Chemical composition and antimicrobial activity of Polish herbhoneys.

    Isidorov, V A; Bagan, R; Bakier, S; Swiecicka, I

    2015-03-15

    The present study focuses on samples of Polish herbhoneys (HHs), their chemical composition and antimicrobial activity. A gas chromatography-mass spectrometry (GC-MS) method was used to analyse eight samples of herbal honeys and three samples of nectar honeys. Their antimicrobial activities were tested on selected Gram-positive (Bacillus cereus, Staphylococcus aureus, Staphylococcus schleiferi) and Gram-negative (Escherichia coli) bacteria, as well as on pathogenic fungi Candida albicans. Ether extracts of HHs showed significant differences in composition but the principal groups found in the extracts were phenolics and aliphatic hydroxy acids typical of royal jelly and unsaturated dicarboxylic acids. In spite of the differences in chemical composition, antimicrobial activity of the extracts of HHs against all the tested microorganisms except E. coli was observed. PMID:25308646

  4. Dynamics of self-propelled nanomotors in chemically active media

    Thakur, Snigdha; Kapral, Raymond

    2011-07-01

    Synthetic chemically powered nanomotors often rely on the environment for their fuel supply. The propulsion properties of such motors can be altered if the environment in which they move is chemically active. The dynamical properties of sphere dimer motors, composed of linked catalytic and noncatalytic monomers, are investigated in active media. Chemical reactions occur at the catalytic monomer and the reactant or product of this reaction is involved in cubic autocatalytic or linear reactions that take place in the bulk phase environment. For these reactions, as the bulk phase reaction rates increase, the motor propulsion velocity decreases. For the cubic autocatalytic reaction, this net effect arises from a competition between a reduction of the nonequilibrium concentration gradient that leads to smaller velocity and the generation of fuel in the environment that tends to increase the motor propulsion. The role played by detailed balance in determining the form of the concentration gradient in the motor vicinity in the active medium is studied. Simulations are carried out using reactive multiparticle collision dynamics and compared with theoretical models to obtain further insight into sphere dimer dynamics in active media.

  5. Advances in mechanisms of activation and deactivation of environmental chemicals.

    Goldstein, J A; Faletto, M B

    1993-01-01

    Environmental chemicals are both activated and detoxified by phase I and phase II enzymes. The principal enzymes involved in phase I reactions are the cytochrome P-450s. The phase II enzymes include hydrolase and the conjugative enzymes such as glucuronyltransferases, glutathione transferases, N-acetyltransferase, and sulfotransferase. Although other phase I and phase II enzymes exist, the present review is limited to these enzymes. Once thought to be a single enzyme, multiple cytochrome P-45...

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

    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.

  7. CHEMICAL COMPOSITION AND ANTI-INFLAMMATORY ACTIVITY OF Roldana platanifolia

    Amira Arciniegas

    2015-11-01

    Full Text Available The chemical study of Roldana platanifolia led to the isolation of β-caryophyllene, five eremophilanolides, chlorogenic acid, and a mixture of β-sitosterol-stigmasterol, β-sitosteryl glucopyranoside, and sucrose. The anti-inflammatory activities of the extracts and isolated products were tested using the 12-O-tetradecanoylphorbol-13-acetate (TPA model of induced acute inflammation. The acetone and methanol extracts showed dose dependent activities (ID50 0.21 and 0.32 mg/ear, respectively, while none of the isolated compounds exhibited relevant edema inhibition. The active extracts were also evaluated with the myeloperoxidase assay technique (MPO to determine their ability to prevent neutrophil infiltration. Results showed that the anti-inflammatory activity was related to the compound’s ability to inhibit pro-inflammatory mediators such as neutrophils.

  8. Risk assessment of endocrine active chemicals: identifying chemicals of regulatory concern.

    Bars, Remi; Fegert, Ivana; Gross, Melanie; Lewis, Dick; Weltje, Lennart; Weyers, Arnd; Wheeler, James R; Galay-Burgos, Malyka

    2012-10-01

    The European regulation on plant protection products (1107/2009) (EC, 2009a), the revisions to the biocides Directive (COM[2009]267) (EC, 2009b), and the regulation concerning chemicals (Regulation (EC) No. 1907/2006 'REACH') (EC.2006) only support the marketing and use of chemical products on the basis that they do not induce endocrine disruption in humans or wildlife species. In the absence of agreed guidance on how to identify and evaluate endocrine activity and disruption within these pieces of legislation a European Centre for Ecotoxicology and Toxicology of Chemicals (ECETOC) task force was formed to provide scientific criteria that may be used within the context of these three legislative documents. The resulting ECETOC technical report (ECETOC, 2009a) and the associated workshop (ECETOC, 2009b) presented a science-based concept on how to identify endocrine activity and disrupting properties of chemicals for both human health and the environment. The synthesis of the technical report and the workshop report was published by the ECETOC task force (Bars et al., 2011a,b). Specific scientific criteria for the determination of endocrine activity and disrupting properties that integrate information from both regulatory (eco)toxicity studies and mechanistic/screening studies were proposed. These criteria combined the nature of the adverse effects detected in studies which give concern for endocrine toxicity with an understanding of the mode of action of toxicity so that adverse effects can be explained scientifically. A key element in the data evaluation is the consideration of all available information in a weight-of-evidence approach. However, to be able to discriminate chemicals with endocrine properties of low concern from those of higher concern (for regulatory purposes), the task force recognised that the concept needed further refinement. Following a discussion of the key factors at a second workshop of invited regulatory, academic and industry scientists

  9. Improvement of Chemically-activated Luciferase Gene Expression Bioassay for Detection of Dioxin-like Chemicals

    2002-01-01

    To improve the chemically-activated luciferase expression (CALUX)bioassay for detection of dioxin-like chemicals (DLCs) based on the toxicity mechanisms of DLCs. Method A recombinant vector was constructed and used to transfect human hepatoma (HepG2). The expression of this vector was 10-100 folds higher than that of pGL2used in previous experiments. The transfected cells showed aromatic hydrocarbon receptor (AhR)-meditated luciferase gene expression. The reliability of luciferase induction in this cell line as a reporter of AhR-mediated toxicity was evaluated, the optimal detection time was examined and a comparison was made by using the commonly used ethoxyresoufin-Odeethylase (EROD) activity induction assay. Result The results suggested that the luciferase activity in recombinant cells was peaked at about 4 h and then decreased to a stable activity by 14 h after TCDD treatment. The detection limit of this cell line was 0.1 lpmol/L, or 10-fold lower than in previous studies, with a linear range from 1 to 100pmol/L, related coefficient of 0.997, and the coefficient of variability (CV) of 15-30%,Conclusion The luciferase induction is 30-fold more sensitive than EROD induction, the detection time is 68 h shorter and the detection procedure is also simpler.

  10. Metabolic activation of chemical carcinogens to reactive electrophiles

    Ionizing radiations and ultraviolet light constitute the principal known physical carcinogens. Likewise, a great variety and large number of chemicals and over 50 DNA and RNA viruses comprise the known chemical and viral carcinogens. These three categories of carcinogenic agents include the great majority of extrinsic agents known to induce cancer in mammals. Man is clearly susceptible to the action of physical and chemical carcinogens and, indeed, was the first species in which the activities of some of these agents were demonstated. It seems certain that viral carcinogenic information is involved in the etiology of at least some human tumors, but ethical and methodological problems have made it difficult to obtain unequivocal data. Given the long availability of experimental carcinogens of these three classes, there is surprisingly little known of their interrelationships in the production of cancer in experimental animals. The objective of this brief review is to present some salient aspects of experimental chemical carcinogenesis and an analysis of how some of these features relate to the mechanisms of action of radiation carcinogens

  11. ANTICANCER ACTIVITY OF ISOLATED CHEMICAL CONSTITUENTS FROM MILIUSA SMITHIAE

    Chonthicha Naphong

    2013-01-01

    Full Text Available Miliusa plants belonging to the family Annonaceae are found in Thailand and have been used as Thai traditional medicines. There have been a few previously reports on the chemical constituents of plants in this genus, describing the presence of aporphine alkaloids, terpenoids, flavonoids, phenylpropanoids, styrylpyrones, bis-styryls and homogentisic acid derivatives. Miliusa smithiae, a new species for Thailand and world, has not been studied chemical composition. The present study described phytochemical study of the leaves and twigs of M. smithiae together with their cytotoxicity. The M. smithiae was selected and percolated with hexane, ethyl acetate, acetone and methanol. The extracts were purified and elucidated chemical structures. The constituent of ethyl acetate extract of M. smithiae has been investigated. We isolated and identified two flavonoid derivatives, 5-hydroxy-3,7,4′-trimetoxyflavone (1 and 5,3′-dihydroxy-3,7,4′-trimetoxyflavone (2. The structures of these compounds were elucidated on the basis of spectroscopic evidence. Studies on ethyl acetate extract of M. smithiae has now resulted the isolation and structural characterization of two flavonoids. Their anticancer activities were evaluated using SRB assays. In this method, compound 2 showed potential activity in cell lines.

  12. Sila-fulleranes: promising chemically active fullerene analogs

    Marsusi, Farah; Qasemnazhand, Mohammad

    2016-07-01

    Density-functional theory (DFT) was applied to investigate the geometry and electronic properties of bare Si60 and H-terminated Si-fullerene. DFT predicts outward sites on a bare Si60 cage. By using π-orbital axis analysis (POAV), it is shown that these sites result from a strong tendency of silicon atoms to form sp3 hybridization bonds. Natural bond orbital (NBO) analysis confirms the sp3 hybridization nature of Si–Si bonds in Si-fulleranes. The quantum confinement effect (QCE) does not affect band gap (BG) so strongly in the size between 1 and 1.7 nm. In contrast, the geometry and symmetry of the cage have a significant influence on the BG. In contrast to their carbon analogs, pentagon rings increase the stability of the cages. Functionalized Si-cages are stable and can be chemically very active. The electronic properties are highly sensitive to the surface chemistry via functionalization with different chemical groups. As a result, BGs and chemical activities of these cages can be drastically tuned through the chemistry of the surface.

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

    Iasmine A.B.S. Alves

    2014-08-01

    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. Chemical constituents from Swietenia macrophylla bark and their antioxidant activity.

    Falah, S; Suzuki, T; Katayama, T

    2008-08-15

    Chemical constituents of the bark of Swietenia macrophylla King (Meliaceae) was investigated not only to develop further bark utilization but also to understand the biochemical function of the bark in the forest environment. A new phenylpropanoid-substituted catechin, namely, swietemacrophyllanin [(2R*,3S*,7"R*)-catechin-8,7"-7,2"-epoxy-(methyl 4",5"-dihydroxyphenylpropanoate)] (1) was isolated from the bark of S. macrophylla together with two known compounds, catechin (2) and epicatechin (3). The structure of 1 was elucidated by spectroscopic data and by comparison of the NMR data with those of catiguanins A and B, phenylpropanoid-substituted epicatechins. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity of the isolated compounds indicated that all of the three compounds have strong activity compared with trolox as a reference. Swietemacrophyllanin (1) had the strongest activity with a 50% inhibitory concentration (IC50) value of 56 microg mL(-1). PMID:19266907

  15. Chemical Signaling and Functional Activation in Colloidosome-Based Protocells.

    Sun, Shiyong; Li, Mei; Dong, Faqin; Wang, Shengjie; Tian, Liangfei; Mann, Stephen

    2016-04-01

    An aqueous-based microcompartmentalized model involving the integration of partially hydrophobic Fe(III)-rich montmorillonite (FeM) clay particles as structural and catalytic building blocks for colloidosome membrane assembly, self-directed membrane remodeling, and signal-induced protocell communication is described. The clay colloidosomes exhibit size- and charge-selective permeability, and show dual catalytic functions involving spatially confined enzyme-mediated dephosphorylation and peroxidase-like membrane activity. The latter is used for the colloidosome-mediated synthesis and assembly of a temperature-responsive poly(N-isopropylacrylamide)(PNIPAM)/clay-integrated hybrid membrane. In situ PNIPAM elaboration of the membrane is coupled to a glucose oxidase (GOx)-mediated signaling pathway to establish a primitive model of chemical communication and functional activation within a synthetic "protocell community" comprising a mixed population of GOx-containing silica colloidosomes and alkaline phosphatase (ALP)-containing FeM-clay colloidosomes. Triggering the enzyme reaction in the silica colloidosomes gives a hydrogen peroxide signal that induces polymer wall formation in a coexistent population of the FeM-clay colloidosomes, which in turn generates self-regulated membrane-gated ALP-activity within the clay microcompartments. The emergence of new functionalities in inorganic colloidosomes via chemical communication between different protocell populations provides a first step toward the realization of interacting communities of synthetic functional microcompartments. PMID:26923794

  16. Transient assembly of active materials fueled by a chemical reaction

    Boekhoven, Job; Hendriksen, Wouter E.; Koper, Ger J. M.; Eelkema, Rienk; van Esch, Jan H.

    2015-09-01

    Fuel-driven self-assembly of actin filaments and microtubules is a key component of cellular organization. Continuous energy supply maintains these transient biomolecular assemblies far from thermodynamic equilibrium, unlike typical synthetic systems that spontaneously assemble at thermodynamic equilibrium. Here, we report the transient self-assembly of synthetic molecules into active materials, driven by the consumption of a chemical fuel. In these materials, reaction rates and fuel levels, instead of equilibrium composition, determine properties such as lifetime, stiffness, and self-regeneration capability. Fibers exhibit strongly nonlinear behavior including stochastic collapse and simultaneous growth and shrinkage, reminiscent of microtubule dynamics.

  17. Chemical Modifications of Hyaluronan using DMTMM-Activated Amidation

    Rydergren, Sara

    2013-01-01

    An alternative approach to chemically modifying hyaluronan (HA) has been investigated. The triazine derivative 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium (DMTMM) has been used to activate carboxylic groups on HA, which react further to form stable amide bonds with primary and secondary amines. The reaction can either be used to couple monoamines to HA or to produce hydrogels by using diamines that form crosslinks between the HA chains. The reaction between HA and DMTMM has been...

  18. Active membrane having uniform physico-chemically functionalized ion channels

    Gerald, II, Rex E; Ruscic, Katarina J; Sears, Devin N; Smith, Luis J; Klingler, Robert J; Rathke, Jerome W

    2012-09-24

    The present invention relates to a physicochemically-active porous membrane for electrochemical cells that purports dual functions: an electronic insulator (separator) and a unidirectional ion-transporter (electrolyte). The electrochemical cell membrane is activated for the transport of ions by contiguous ion coordination sites on the interior two-dimensional surfaces of the trans-membrane unidirectional pores. One dimension of the pore surface has a macroscopic length (1 nm-1000 .mu.m) and is directed parallel to the direction of an electric field, which is produced between the cathode and the anode electrodes of an electrochemical cell. The membrane material is designed to have physicochemical interaction with ions. Control of the extent of the interactions between the ions and the interior pore walls of the membrane and other materials, chemicals, or structures contained within the pores provides adjustability of the ionic conductivity of the membrane.

  19. Physico-chemical characterization of powdered activated carbons obtained by thermo-chemical conversion of brown municipal waste

    Momčilović Milan Z.; Purenović Milovan M.; Miljković Milena N.; Bojić Aleksandar Lj.; Zarubica Aleksandra R.; Ranđelović Marjan S.

    2011-01-01

    Cones of the European Black pine and Horse chestnut kernel, regarded as brown municipal waste, was utilized in this work as a precursor for powdered activated carbons. Chemical activation was employed at 500°C in inert atmosphere of nitrogen. Standard physico-chemical analyses were performed to examine obtained products. FTIR method was employed to determine fuctional groups which were found to be typical for activated carbons. Acidic oxygen groups were quantitatively determined using B...

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

    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.

  1. Improvement of activity and stability of chloroperoxidase by chemical modification

    Wang Min

    2007-05-01

    Full Text Available Abstract Background Enzymes show relative instability in solvents or at elevated temperature and lower activity in organic solvent than in water. These limit the industrial applications of enzymes. Results In order to improve the activity and stability of chloroperoxidase, chloroperoxidase was modified by citraconic anhydride, maleic anhydride or phthalic anhydride. The catalytic activities, thermostabilities and organic solvent tolerances of native and modified enzymes were compared. In aqueous buffer, modified chloroperoxidases showed similar Km values and greater catalytic efficiencies kcat/Km for both sulfoxidation and oxidation of phenol compared to native chloroperoxidase. Of these modified chloroperoxidases, citraconic anhydride-modified chloroperoxidase showed the greatest catalytic efficiency in aqueous buffer. These modifications of chloroperoxidase increased their catalytic efficiencies for sulfoxidation by 12%~26% and catalytic efficiencies for phenol oxidation by 7%~53% in aqueous buffer. However, in organic solvent (DMF, modified chloroperoxidases had lower Km values and higher catalytic efficiencies kcat/Km than native chloroperoxidase. These modifications also improved their thermostabilities by 1~2-fold and solvent tolerances of DMF. CD studies show that these modifications did not change the secondary structure of chloroperoxidase. Fluorescence spectra proved that these modifications changed the environment of tryptophan. Conclusion Chemical modification of epsilon-amino groups of lysine residues of chloroperoxidase using citraconic anhydride, maleic anhydride or phthalic anhydride is a simple and powerful method to enhance catalytic properties of enzyme. The improvements of the activity and stability of chloroperoxidase are related to side chain reorientations of aromatics upon both modifications.

  2. Influences of chemical activators on incinerator bottom ash.

    Qiao, X C; Cheeseman, C R; Poon, C S

    2009-02-01

    This research has applied different chemical activators to mechanically and thermally treated fine fraction (material. IBA has been milled and thermally treated at 800 degrees C (TIBA). The TIBA produced was blended with Ca(OH)(2) and evaluated for setting time, reactivity and compressive strength after the addition of 0.0565 mole of Na(2)SO(4), K(2)SO(4), Na(2)CO(3), K(2)CO(3), NaOH, KOH and CaCl(2) into 100g of binder (TIBA+Ca(OH)(2)). The microstructures of activated IBA and hydrated samples have been characterized by X-ray diffraction (XRD) and thermogravimetry (TG) analysis. Thermal treatment is found to produce gehlenite (Ca(2)Al(2)SiO(7)), wollastonite (CaSiO(3)) and mayenite (Ca(12)Al(14)O(33)) phases. The thermally treated IBA samples are significantly more reactive than the milled IBA. The addition of Na(2)CO(3) can increase the compressive strength and calcium hydroxide consumption at 28-day curing ages. However, the addition of Na(2)SO(4), K(2)SO(4), K(2)CO(3), NaOH and KOH reduces the strength and hydration reaction. Moreover, these chemicals produce more porous samples due to increased generation of hydrogen gas. The addition of CaCl(2) has a negative effect on the hydration of TIBA samples. Calcium aluminium oxide carbonate sulphide hydrate (Ca(4)Al(2)O(6)(CO(3))(0.67)(SO(3))(0.33)(H(2)O)(11)) is the main hydration product in the samples with activated IBA, except for the sample containing CaCl(2). PMID:18718749

  3. Influences of chemical activators on incinerator bottom ash

    This research has applied different chemical activators to mechanically and thermally treated fine fraction (2 and evaluated for setting time, reactivity and compressive strength after the addition of 0.0565 mole of Na2SO4, K2SO4, Na2CO3, K2CO3, NaOH, KOH and CaCl2 into 100 g of binder (TIBA+Ca(OH)2). The microstructures of activated IBA and hydrated samples have been characterized by X-ray diffraction (XRD) and thermogravimetry (TG) analysis. Thermal treatment is found to produce gehlenite (Ca2Al2SiO7), wollastonite (CaSiO3) and mayenite (Ca12Al14O33) phases. The thermally treated IBA samples are significantly more reactive than the milled IBA. The addition of Na2CO3 can increase the compressive strength and calcium hydroxide consumption at 28-day curing ages. However, the addition of Na2SO4, K2SO4, K2CO3, NaOH and KOH reduces the strength and hydration reaction. Moreover, these chemicals produce more porous samples due to increased generation of hydrogen gas. The addition of CaCl2 has a negative effect on the hydration of TIBA samples. Calcium aluminium oxide carbonate sulphide hydrate (Ca4Al2O6(CO3)0.67(SO3)0.33(H2O)11) is the main hydration product in the samples with activated IBA, except for the sample containing CaCl2

  4. Cosmetics chemical composition characterization by instrumental neutron activation analysis

    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 8x1011ncm-2s-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)

  5. Instrumental neutron activation analysis. A valuable link in chemical metrology

    A systematic experimental approach to the demonstration of viability of instrumental neutron activation analysis (INAA) in chemical metrology is provided. The practical approach was derived from a complete survey of uncertainty components that affect the INAA measurement process. These uncertainty components were classified by their magnitude and origin and subsequently minimized by appropriate steps in the INAA process. The process was tested with the INAA determination of Cr in SRM 1152A stainless steel; the Cr value is certified at 17.76% with an estimated uncertainty of 0.04% (0.23% relative). The INAA results from this procedure are in agreement with these specifications. Similar procedures have been applied to INAA multi-element determinations in a high temperature alloy. Agreement with available consensus values was demonstrated in the alloy. The guidelines on the determination of uncertainty were fully met, providing through INAA a valuable independent non-destructive tool in chemical measurements of metrological value such as required in the CCQM key comparisons. (author)

  6. Biphasic flow in a chemically active porous medium

    Darmon, Alexandre; Salez, Thomas; Dauchot, Olivier

    2014-01-01

    We study the problem of the transformation of a given reactant species into an immiscible product species, as they flow through a chemically active porous medium. We derive the equation governing the evolution of the volume fraction of the species -- in a one-dimensional macroscopic description --, identify the relevant dimensionless numbers, and provide simple models for capillary pressure and relative permeabilities, which are quantities of crucial importance when tackling multiphase flows in porous media. We set the domain of validity of our models and discuss the importance of viscous coupling terms in the extended Darcy's law. We investigate numerically the steady regime and demonstrate that the spatial transformation rate of the species along the reactor is non-monotonous, as testified by the existence of an inflection point in the volume fraction profiles. We obtain the scaling of the location of this inflection point with the dimensionless lengths of the problem. Eventually, we provide key elements fo...

  7. Chemical weapons detection by fast neutron activation analysis techniques

    A neutron diagnostic experimental apparatus has been tested for nondestructive verification of sealed munitions. Designed to potentially satisfy a significant number of van-mobile requirements, this equipment is based on an easy to use industrial sealed tube neutron generator that interrogates the munitions of interest with 14 MeV neutrons. Gamma ray spectra are detected with a high purity germanium detector, especially shielded from neutrons and gamma ray background. A mobile shell holder has been used. Possible configurations allow the detection, in continuous or in pulsed modes, of gamma rays from neutron inelastic scattering, from thermal neutron capture, and from fast or thermal neutron activation. Tests on full scale sealed munitions with chemical simulants show that those with chlorine (old generation materials) are detectable in a few minutes, and those including phosphorus (new generation materials) in nearly the same time. (orig.)

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

    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

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

    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.

  10. Dynamic model for selective metabolic activation in chemical carcinogenesis

    Selkirk, J.K.; MacLeod, M.C.

    1980-01-01

    Theoretical calculations predict the relative ease of formation of carbonium ions from 7,8-dihydro-7,8-dihydroxybenzo(a)pyrene-9,10-oxide or from either of the 2 symmetrical bay regions of B(e)P, and suggest their attraction to cellular nucleophiles. When both isomers were metabolized by hamster embryo fibroblasts (HEF) and the products analyzed, the results showed that the probable reason for benzo(e)pyrene's lack of carcinogenicity was its metabolic preference to attack the molecule away from the bay-region area. Particularly striking was the absence of any evidence for the formation of a significant amount of B(e)P-9,10-dihydrodiol. This suggests a metabolic basis for the relative lack of carcinogenic and mutagenic activity of B(e)P. The reason for this is not clear but may be due to physical or chemical factors such as membrane solubility or stereochemical requirements of the active site of the enzyme. The bay-region theory of PAH carcinogenesis predicts that carbonium ion formation from 9,10-dihydro-9,10-dihydroxybenzo(e)pyrene-11, 12-oxide, if formed, would be energetically favorable. Thus, the inability of HEF and microcomes to form B(e)P-9,10-dihydrodiol, the precursor of its potentially highly reactive diol-epoxide, would explain the relative inertness of B(e)P in several biological systems. As the subtle biochemical interactions of the various carcinogen intermediates become clarified, it becomes apparent that susceptibility and resistance to malignant transformation are based on a complex set of both chemical and physical parameters. It is becoming clear that metabolism kinetics, membrane interaction, and the role of nuclear metabolism help dictate the passage of the carcinogen and its reactive intermediates into and through the metabolic machinery of the cell. (ERB)

  11. Chemical Composition and Antioxidant Activity of Walnut Pollen Samples

    Sina COSMULESCU

    2015-12-01

    Full Text Available Chemical composition of pollen is highly varied depending on the plant species from which it comes and has been the subject of numerous comparative studies. The aim of this study was to determine chemical composition and antioxidant activity of walnut pollen samples and compare them with those of bee pollen. Total phenols content, total flavonoids content, antioxidant activity and mineral composition were studied using walnut pollen samples from three walnut genotypes cultivated in Romania. Total phenols content was determined by colorimetric assay and their amount varied between 10.8 and 17.64 mgGAE/g per genotype. Determination of flavonoids was done by aluminium nitrate colorimetric method and total flavonoid contents in walnut pollen ranged from 7.32 to 7.95 mgQE/g. The antioxidant capacity of pollen extracts was assessed through the scavenging effects on DPPH and a concentration-dependent genotype, and it varied between 13.78 and 15.04 mg Trolox/g. In terms of mineral composition, walnut pollen appears to be a good source of potassium (859.14 mg/100 g, magnesium (263.77 mg/100 g, calcium (71.72 mg/100 g, iron (27.19 mg/100 g, sodium (10.52 mg/100 g, zinc (5.69 mg/100 g, manganese (3.98 mg/100 g, copper (1.28 mg/100 g, chromium (0.39 mg/100 g and selenium (0.036 mg/100 g. The results obtained indicate that walnut pollen is an important source of total phenols showing antioxidant properties and mineral composition that could be beneficial to human health.

  12. Chemical profiling of Centella asiatica under different extraction solvents and its antibacterial activity, antioxidant activity

    Supawan Rattanakom; Patchanee Yasurin

    2015-01-01

    Centella asiatica (L) urban, synonym Hydrocotyle asiatica, is found almost all over the world. This plant is famous in Ayurvedic medicine and used in the management of central nervous system, skin and gastrointestinal disorder. Thus this research had been done to evaluate the effect of solvent extraction (Ethanol, Chloroform and Hexane) of C. asiatica on chemical profile, antioxidant activity and antibacterial activity against some foodborne pathogens. The result showed that all solvents (et...

  13. Preparation and Characterization of Sisal Fiber-based Activated Carbon by Chemical Activation with Zinc Chloride

    Sisal fiber, an agricultural resource abundantly available in China, has been used as raw material to prepare activated carbon with high surface area and huge pore volume by chemical activation with zinc chloride. The orthogonal test was designed to investigate the influence of zinc chloride concentration, impregnation ratio, activation temperature and activation time on preparation of activated carbon. Scanning electron micrograph, Thermo-gravimetric, N2-adsorption isotherm, mathematical models such as t-plot, H-K equation, D-R equation and BJH methods were used to characterize the properties of the prepared carbons and the activation mechanism was discussed. The results showed that ZnCl2 changed the pyrolysis process of sisal fiber. Characteristics of activated carbon are: BET surface area was 1628 m2/g, total pore volume was 1.316 m3/g and ratio of mesopore volume to total pore volume up to 94.3%. These results suggest that sisal fiber is an attractive source to prepare mesoporous high-capacity activated carbon by chemical activation with zinc chloride

  14. Chemical Composition and Biological Activities of Gerbera anandria

    Fa He

    2014-04-01

    Full Text Available Gerbera anandria (Compositae was extracted with 75% ethanol and the residue was fractionated using light petroleum, chloroform and ethyl acetate. The constituents of the extracts were separated by column chromatography employing solvents of different polarity. Column chromatography of the light petroleum fraction resulted in the isolation of methyl hexadecanoate, while the chloroform fraction afforded xanthotoxin, 2-hydroxy-6-methylbenzoic acid, 7-hydroxy-1(3H-isobenzofuranone, a mixture of β-sitosterol and stigmasterol, and 8-methoxysmyrindiol and the ethyl acetate fraction gave gerberinside, apigenin-7-O-β-d-glucopyranoside and quercetin. A new coumarin, 8-methoxysmyrindiol, was found. The chemical structures of the isolated compounds were established by MS and NMR (HSQC, HMBC. Free radical scavenging and cytotoxic activities of crude extracts and 8-methoxysmyrindiol were further investigated. The ethyl acetate phase exerted the strongest DPPH free radical scavenging activity in comparison to the other fractions. The coumarin 8-methoxysmyrindiol demonstrated cytotoxicity against multiple human cancer cell lines, with the highest potency in HepG2 cells.

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

    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. Chemically Induced and Light-Independent Cryptochrome Photoreceptor Activation

    Gesa Rosenfeldt; Rafael Mu(n)oz Viana; Henning D.Mootz; Albrecht G.Von Arnim; Alfred Batschauer

    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.

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

    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.

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

    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.

  19. Chaotic Temperatures vs Coefficients of Thermodynamic Activity The Advantage of the Method of Chemical Dynamics

    Zilbergleyt, B

    2002-01-01

    The article compares traditional coefficients of thermodynamic activity as a parameter related to individual chemical species to newly introduced reduced chaotic temperatures as system characteristics, both regarding their usage in thermodynamic simulation of open chemical systems. Logical and mathematical backgrounds of both approaches are discussed. It is shown that usage of reduced chaotic temperatures and the Method of Chemical Dynamics to calculate chemical and phase composition in open chemical systems is much less costly, easier to perform and potentially leads to better precision.

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

    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.)

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

    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

  2. Chemical synthesis and immunosuppressive activity of dipalmitoyl phosphatidylinositol hexamannoside.

    Ainge, Gary D; Compton, Benjamin J; Hayman, Colin M; Martin, William John; Toms, Steven M; Larsen, David S; Harper, Jacquie L; Painter, Gavin F

    2011-06-17

    Phosphatidylinositol mannosides (PIMs) isolated from mycobacteria have been identified as an important class of phosphoglycolipids with significant immune-modulating properties. We present here the synthesis of dipalmitoyl phosphatidylinositol hexamannoside (PIM(6)) 1 and the first reported functional biology of a synthetic PIM(6). Key steps in the synthetic protocol included the selective glycosylation of an inositol 2,6-diol with a suitably protected mannosyl donor and construction of the glycan core utilizing a [3 + 4] thio-glycosylation strategy. The target 1 was purified by reverse phase chromatography and characterized by standard spectroscopic methods, HPLC, and chemical modification by deacylation to dPIM(6). The (1)H NMR spectrum of synthetic dPIM(6) obtained from 1 matched that of dPIM(6) obtained from nature. PIM(6) (1) exhibited dendritic cell-dependent suppression of CD8(+) T cell expansion in a human mixed lymphocyte reaction consistent with the well established immunosuppressive activity of whole mycobacteria. PMID:21574597

  3. Heat-activated Plasmonic Chemical Sensors for Harsh Environments

    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

  4. Microbial dechlorination activity during and after chemical oxidant treatment

    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.

  5. Chemical surface tuning electrocatalysis of redox-active nanoparticles

    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...

  6. Advanced deposition model for thermal activated chemical vapor deposition

    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

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

    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

  8. Effect of activation agents on the surface chemical properties and desulphurization performance of activated carbon

    2010-01-01

    Flue gas pollution is a serious environmental problem that needs to be solved for the sustainable development of China.The surface chemical properties of carbon have great influence on its desulphurization performance.A series of activated carbons (ACs) were prepared using HNO3,H2O2,NH3·H2O and steam as activation agents with the aim to introduce functional groups to carbon surface in the ACs preparation process.The ACs were physically and chemically characterized by iodine and SO2 adsorption,ultimate analysis,Boehm titration,and temperature-programmed reduction (TPR).Results showed that the iodine number and desulphurization capacity of NH3·H2O activated carbon (AC-NH3) increase with both activation time,and its desulphurization capacity also increases with the concentration of activation agent.However,HNO3 activated carbon (AC-HNO3) and H2O2 activated carbon (AC-H2O2) exhibit more complex behavior.Only their iodine numbers increase monotonously with activation time.Compared with steam activated AC (AC-H2O),the nitrogen content increases 0.232% in AC-NH3 and 0.077% in AC-HNO3.The amount of total basic site on AC-HNO3 is 0.19 mmol·g-1 higher than that on AC-H2O.H2O2 activation introduces an additional 0.08 mmol·g-1 carboxyl groups to AC surface than that introduced by steam activation.The desulphurization capacity of ACs in simulate flue gas desulphurization decreases as follows: AC-NH3 > AC-HNO3 > AC-H2O2 > AC-H2O.This sequence is in accord with the SO2 catalytic oxidation/oxidation ratio in the absence of oxygen and the oxidation property reflected by TPR.In the presence of oxygen,all adsorbed SO2 on ACs can be oxidized into SO3.The desulphurization capacity increases differently according to the activation agents;the desulphurization capacity of AC-NH3 and AC-HNO3 improves by 4.8 times,yet AC-H2O increases only by 2.62 as compared with the desulphurization of corresponding ACs in absence of oxygen.

  9. Active targeting in a random porous medium by chemical swarm robots with secondary chemical signaling

    Grančič, Peter; Štěpánek, František

    2011-08-01

    The multibody dynamics of a system of chemical swarm robots in a porous environment is investigated. The chemical swarm robots are modeled as Brownian particles capable of delivering an encapsulated chemical payload toward a given target location and releasing it in response to an external stimulus. The presence of chemical signals (chemo-attractant) in the system plays a crucial role in coordinating the collective movement of the particles via chemotaxis. For a number of applications, such as distributed chemical processing and targeted drug delivery, the understanding of factors that govern the collective behavior of the particles, especially their ability to localize a given target, is of immense importance. A hybrid modeling methodology based on the combination of the Brownian dynamics method and diffusion problem coupled through the chemotaxis phenomena is used to analyze the impact of a varying signaling threshold and the strength of chemotaxis on the ability of the chemical robots to fulfill their target localization mission. The results demonstrate that the selected performance criteria (the localization half time and the success rate) can be improved when an appropriate signaling process is chosen. Furthermore, for an optimum target localization strategy, the topological complexity of the porous environment needs to be reflected.

  10. [Advances in studies on chemical constituents and biological activities of Desmodium species].

    Liu, Chao; Wu, Ying; Zhang, Qian-Jun; Kang, Wen-Yi; Zhang, Long; Zhou, Qing-Di

    2013-12-01

    The chemical constituents isolated from Desmodium species (Leguminosae) included terpenoids, flavonoids, steroids, alkaloids compounds. Modem pharmacological studies have showed that the Desmodium species have antioxidant, antibacterial, anti-inflammatory, hepatoprotective, diuretic, antipyretic, analgesic and choleretic activity. This article mainly has reviewed the research advances of chemical constituents and biological activities of Desmodium species since 2003. PMID:24791478

  11. Combined Chemical Activation and Fenton Degradation to Convert Waste Polyethylene into High-Value Fine Chemicals.

    Chow, Cheuk-Fai; Wong, Wing-Leung; Ho, Keith Yat-Fung; Chan, Chung-Sum; Gong, Cheng-Bin

    2016-07-01

    Plastic waste is a valuable organic resource. However, proper technologies to recover usable materials from plastic are still very rare. Although the conversion/cracking/degradation of certain plastics into chemicals has drawn much attention, effective and selective cracking of the major waste plastic polyethylene is extremely difficult, with degradation of C-C/C-H bonds identified as the bottleneck. Pyrolysis, for example, is a nonselective degradation method used to crack plastics, but it requires a very high energy input. To solve the current plastic pollution crisis, more effective technologies are needed for converting plastic waste into useful substances that can be fed into the energy cycle or used to produce fine chemicals for industry. In this study, we demonstrate a new and effective chemical approach by using the Fenton reaction to convert polyethylene plastic waste into carboxylic acids under ambient conditions. Understanding the fundamentals of this new chemical process provides a possible protocol to solve global plastic-waste problems. PMID:27168079

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

    Vetiver roots have been utilized for the preparation of activated carbon (AC) by chemical activation with different impregnation ratios of phosphoric acid, XP (g H3PO4/g precursor): 0.5:1; 1:1 and 1.5:1. Textural characterization, determined by nitrogen adsorption at 77 K shows that mixed microporous and mesoporous structures activated carbons (ACs) with high surface area (>1000 m2/g) and high pore volume (up to 1.19 cm3/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 (R2) and the normalized standard deviation Δq (%) 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 and phenol

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

    Altenor, Sandro [COVACHIMM, EA 3592 Universite des Antilles et de la Guyane, BP 250, 97157 Pointe a Pitre Cedex, Guadeloupe (France); LAQUE, Universite Quisqueya d' Haiti, Port-au-Prince (Haiti); Carene, Betty [COVACHIMM, EA 3592 Universite des Antilles et de la Guyane, BP 250, 97157 Pointe a Pitre Cedex, Guadeloupe (France); Emmanuel, Evens [LAQUE, Universite Quisqueya d' Haiti, Port-au-Prince (Haiti); Lambert, Jacques; Ehrhardt, Jean-Jacques [Laboratoire de Chimie Physique et Microbiologie pour l' Environnement, UMR 7564 CNRS-Nancy Universities, 405 rue de Vandoeuvre, F 54600 Villers-les-Nancy Cedex (France); Gaspard, Sarra, E-mail: sgaspard@univ-ag.fr [COVACHIMM, EA 3592 Universite des Antilles et de la Guyane, BP 250, 97157 Pointe a Pitre Cedex, Guadeloupe (France)

    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{sub P} (g H{sub 3}PO{sub 4}/g precursor): 0.5:1; 1:1 and 1.5:1. Textural characterization, determined by nitrogen adsorption at 77 K shows that mixed microporous and mesoporous structures activated carbons (ACs) with high surface area (>1000 m{sup 2}/g) and high pore volume (up to 1.19 cm{sup 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{sup 2}) and the normalized standard deviation {Delta}q (%) 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

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

    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

  15. CHEMICALS

    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

  16. Physico-chemical characterization of powdered activated carbons obtained by thermo-chemical conversion of brown municipal waste

    Momčilović Milan Z.

    2011-01-01

    Full Text Available Cones of the European Black pine and Horse chestnut kernel, regarded as brown municipal waste, was utilized in this work as a precursor for powdered activated carbons. Chemical activation was employed at 500°C in inert atmosphere of nitrogen. Standard physico-chemical analyses were performed to examine obtained products. FTIR method was employed to determine fuctional groups which were found to be typical for activated carbons. Acidic oxygen groups were quantitatively determined using Boehm titrations. It was established that carboxylic groups on pine cone activated carbon, and phenolic groups on chestnut kernel activated carbon were dominant from all acidic oxygen groups. Since both contact pH and pHPZC were determined to be fairly acidic, it could be concluded that obtained activated carbons belong to L-type. Shape and layout of micrometer dimensioned particles were observed by scanning electron microscopy. Particles of different shapes and dimensions along with small cracks and wide crevices and voids were noticed. Textural analysis was used to determine specific surface area and pore distribution of obtained activated carbons. Obtained products possess highly developed surface area and wide pore distribution.

  17. Evaluation of Kinase Activity Profiling Using Chemical Proteomics.

    Ruprecht, Benjamin; Zecha, Jana; Heinzlmeir, Stephanie; Médard, Guillaume; Lemeer, Simone; Kuster, Bernhard

    2015-12-18

    Protein kinases are important mediators of intracellular signaling and are reversibly activated by phosphorylation. Immobilized kinase inhibitors can be used to enrich these often low-abundance proteins, to identify targets of kinase inhibitors, or to probe their selectivity. It has been suggested that the binding of kinases to affinity beads reflects a kinase's activation status, a concept that is under considerable debate. To assess the merits of the idea, we performed a series of experiments including quantitative phosphoproteomics and purification of kinases by single or mixed affinity matrices from signaling activated or resting cancer cells. The data show that mixed affinity beads largely bind kinases independent of their activation status, and experiments using individual immobilized kinase inhibitors show mixed results in terms of preference for binding the active or inactive conformation. Taken together, activity- or conformation-dependent binding to such affinity resins depends (i) on the kinase, (ii) on the affinity probe, and (iii) on the activation status of the lysate or cell. As a result, great caution should be exercised when inferring kinase activity from such binding data. The results also suggest that assaying kinase activity using binding data is restricted to a limited number of well-chosen cases. PMID:26378887

  18. Hydrogeology, Chemical and Microbial Activity Measurement Through Deep Permafrost

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

    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 permafrost-formation process. Nonbacteriogenic CH4 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 CH4 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. ?? 2010 The Author(s). Journal compilation ?? 2010 National Ground Water Association.

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

    Juraithip Wungsintaweekul; Worapan Sitthithaworn; Waraporn Putalun; Hartwig W. Pfeifhoffer; Adelheid Brantner

    2010-01-01

    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 Candid...

  20. Chemically sulfated natural galactomannans with specific antiviral and anticoagulant activities.

    Muschin, Tegshi; Budragchaa, Davaanyam; Kanamoto, Taisei; Nakashima, Hideki; Ichiyama, Koji; Yamamoto, Naoki; Shuqin, Han; Yoshida, Takashi

    2016-08-01

    Naturally occurring galactomannans were sulfated to give sulfated galactomannans with degrees of substitution of 0.7-1.4 per sugar unit and molecular weights of M¯n=0.6×10(4)-2.4×10(4). Sulfated galactomannans were found to have specific biological activities in vitro such as anticoagulant, anti-HIV and anti-Dengue virus activities. The biological activities were compared with those of standard dextran and curdlan sulfates, which are polysaccharides with potent antiviral activity and low cytotoxicity. It was found that sulfated galactomannans had moderate to high anticoagulant activity, 13.4-36.6unit/mg, compared to that of dextran and curdlan sulfates, 22.7 and 10.0unit/mg, and high anti-HIV and anti-Dengue virus activities, 0.04-0.8μg/mL and 0.2-1.1μg/mL, compared to those curdlan sulfates, 0.1μg/mL, respectively. The cytotoxicity on MT-4 and LCC-MK2 cells was low. Surface plasmon resonance (SPR) of sulfated galactomannans revealed strong interaction with poly-l-lysine as a model compound of virus proteins, and suggested that the specific biological activities might originate in the electrostatic interaction of negatively charged sulfate groups of sulfated galactomannans and positively charged amino groups of surface proteins of viruses. These results suggest that sulfated galactomannans effectively prevented the infection of cells by viruses and the degree of substitution and molecular weights played important roles in the biological activities. PMID:27154517

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

    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.

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

    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.

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

    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 as rega...... of Chemical Engineers....

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

    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)

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

    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. Anti

  6. Chemical Modification of Papain and Subtilisin: An Active Site Comparison

    St-Vincent, Mireille; Dickman, Michael

    2004-01-01

    An experiment using methyle methanethiosulfonate (MMTS) and phenylmethylsulfonyl flouride (PMSF) to specifically modify the cysteine and serine residues in the active sites of papain and subtilism respectively is demonstrated. The covalent modification of these enzymes and subsequent rescue of papain shows the beginning biochemist that proteins…

  7. Chemical constituents and biological activities of Garcinia cowa Roxb.

    Thunwadee Ritthiwigrom

    2013-06-01

    Full Text Available Garcinia cowa is an abundant source of bioactive phytochemicals. Phytochemical investigations of the plant parts indicated that the fruit, twig and stem are the best source of secondary metabolites, providing flavonoids, phloroglucinols and xanthones respectively. Seventy-eight of these compounds have been identified from the plant and several have interesting pharmacological activities.

  8. Chemical constituents and biological activities of Garcinia cowa Roxb.

    Thunwadee Ritthiwigrom

    2013-01-01

    Garcinia cowa is an abundant source of bioactive phytochemicals. Phytochemical investigations of the plant parts indicated that the fruit, twig and stem are the best source of secondary metabolites, providing flavonoids, phloroglucinols and xanthones respectively. Seventy-eight of these compounds have been identified from the plant and several have interesting pharmacological activities.

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

    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…

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

    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.

  11. Antimicrobial activity and chemical investigation of Brazilian Drosera.

    Ferreira, Dalva Trevisan; Andrei, César Cornélio; Saridakis, Halha Ostrensky; Faria, Terezinha de Jesus; Vinhato, Elisângela; Carvalho, Kátia Eliane; Daniel, Juliana Feijó Souza; Machado, Sílvio Luiz; Saridakis, Dennis Panayotis; Braz-Filho, Raimundo

    2004-11-01

    The antimicrobial activity of three different extracts (hexanic, ethyl acetate, methanol) obtained from Brazilian Drosera species (D. communis, D. montana var. montana, D. brevifolia, D. villosa var. graomogolensis, D. villosa var. villosa, Drosera sp. 1, and Drosera sp. 2 ) were tested against Staphylococcus aureus (ATCC 25923), Enterococcus faecium (ATCC23212), Pseudomonas aeruginosa (ATCC27853), Escherichia coli (ATCC11229), Salmonella choleraesuis (ATCC10708), Klebsiella pneumoniae (ATCC13883), and Candida albicans (a human isolate). Better antimicrobial activity was observed with D. communis and D. montana var. montana ethyl acetate extracts. Phytochemical analyses from D. communis, D. montana var. montana and D. brevifolia yielded 5-hydroxy-2-methyl-1,4-naphthoquinone (plumbagin); long chain aliphatic hydrocarbons were isolated from D. communis and from D. villosa var. villosa, a mixture of long chain aliphatic alcohols and carboxylic acids, was isolated from D. communis and 3b-O-acetylaleuritolic acid from D. villosa var. villosa. PMID:15654434

  12. Antimicrobial activity and chemical investigation of Brazilian Drosera

    Dalva Trevisan Ferreira

    2004-11-01

    Full Text Available The antimicrobial activity of three different extracts (hexanic, ethyl acetate, methanol obtained from Brazilian Drosera species (D. communis, D. montana var. montana, D. brevifolia, D. villosa var. graomogolensis, D. villosa var. villosa, Drosera sp. 1, and Drosera sp. 2 were tested against Staphylococcus aureus (ATCC 25923, Enterococcus faecium (ATCC23212, Pseudomonas aeruginosa (ATCC27853, Escherichia coli (ATCC11229, Salmonella choleraesuis (ATCC10708, Klebsiella pneumoniae (ATCC13883, and Candida albicans (a human isolate. Better antimicrobial activity was observed with D. communis and D. montana var. montana ethyl acetate extracts. Phytochemical analyses from D. communis, D. montana var. montana and D. brevifolia yielded 5-hydroxy-2-methyl-1,4-naphthoquinone (plumbagin; long chain aliphatic hydrocarbons were isolated from D. communis and from D. villosa var. villosa, a mixture of long chain aliphatic alcohols and carboxylic acids, was isolated from D. communis and 3b-O-acetylaleuritolic acid from D. villosa var. villosa.

  13. Chemical study of Sinningia allagophylla guided by antiproliferative activity assays

    Activity guided fractionation of Sinningia allagophylla (Mart.) Wiehler ethanolic extract yielded a new benzochromene 8-methoxylapachenol, besides seven known compounds: lapachenol, sitosteryl oleate, sitosteryl linoleate, stigmasteryl oleate, stigmasteryl linoleate, dunniol and tectoquinone. Extract, fractions, and compounds lapachenol, 8-methoxylapachenol, and dunniol were tested in vitro against human cancer cell lines U251 (glioma, CNS), MCF-7 (breast), NCI-ADR/RES (drug-resistant ovarian), 786-0 (kidney), NCI-H460 (lung, no small cells), PC-3 (prostate), OVCAR-3 (ovarian), HT-29 (colon), K562 (leukemia) and against VERO, a normal cell line. The most active compound was dunniol, which inhibited the growth of U251, MCF-7, NCI-ADR/RES, OVCAR-3 and K562 cell lines. (author)

  14. Antimicrobial Activity and Chemical Composition of Albanian Oregano

    EDLIRA NEZA

    2015-12-01

    Full Text Available ATCC 25922, Staphylococcus aureus ATCC 6538, Pseudomonas spp, Candida albicans ATCC 10231, Listeria monocytogenes ATCC 19111 and Salmonella typhimurium ATCC 14028. Antimicrobial activity of oregano essential oil was also tested against: E. coli, P. aeruginosa, S. aureus and C. albicans. Only oregano essential oil was active against microorganisms selected. Essential oil of oregano was analysed by GC-MS. Eighteen components were identified representing 99.48 % of the oil. Monoterpenes phenols and derivatives (borneol, 4-terpineol, carvacrol methyl ether, thymoquinone, thymol, carvacrol represented 74.66 % of essential oil. Carvacrol, p-cymene, thymol and γ-terpinene were the main components. Sesquiterpenes such as trans-caryophyllene, α-humulene, β-bisabolene, δ- Cadinene, caryophyllene oxide were also found.

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

    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)

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

    Valéria da Veiga Dias; Marcelo da Silva Schuster; Renato Rodrigues Dias

    2013-01-01

    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 ...

  17. Chemical Inhibitors for Biomass Yield Reduction in Activated Sludge

    Mayhew, Maxine Eleanor

    1999-01-01

    Increasing legislation and rising treatment and disposal costs have promoted optimisation of the activated sludge process to encompass reduction of waste biomass. Manipulation of process control such as increasing sludge age and decreasing food to microorganism ratio can lower waste sludge production, but capital works as well as increased operating costs in the form of power requirement for oxygen supply may be required. The need for a cost effective method of biomass reductio...

  18. Antimicrobial activity and chemical investigation of Brazilian Drosera

    Dalva Trevisan Ferreira; César Cornélio Andrei; Halha Ostrensky Saridakis; Terezinha de Jesus Faria; Elisângela Vinhato; Kátia Eliane Carvalho; Juliana Feijó de Souza Daniel; Sílvio Luiz Machado; Dennis Panayotis Saridakis; Raimundo Braz-Filho

    2004-01-01

    The antimicrobial activity of three different extracts (hexanic, ethyl acetate, methanol) obtained from Brazilian Drosera species (D. communis, D. montana var. montana, D. brevifolia, D. villosa var. graomogolensis, D. villosa var. villosa, Drosera sp. 1, and Drosera sp. 2 ) were tested against Staphylococcus aureus (ATCC 25923), Enterococcus faecium (ATCC23212), Pseudomonas aeruginosa (ATCC27853), Escherichia coli (ATCC11229), Salmonella choleraesuis (ATCC10708), Klebsiella pneumoniae (ATCC1...

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

    Iasmine A.B.S. Alves; Henrique M. Miranda; Luiz A. L. Soares; Karina P. Randau

    2014-01-01

    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, amebicid...

  20. Chemicals profiling and antioxidants activities of Acacia seeds

    Ennajeh, Imen; Laajel, Mejda; Khouja, Mohamed-Larbi; Ferchichi, Ali; Nasri, Nizar

    2011-01-01

    This study reported investigations on phytochemical screening and antioxidants activities of seeds from seven Acacia species. Storage proteins and mineral contents were determined. The seed extracts of Acacia species were evaluated for their total phenols, flavonoids, carotenoids contents and total antioxidant capacity assessed by 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays. Total protein content ranged from 99.49 (Acacia cyclops...

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

    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)

  2. Effect of chemicals on fungal alpha-amylase activity.

    Ali, F S; Abdel-Moneim, A A

    1989-01-01

    The effect of 8 growth regulators at concentrations of 1,000, 5,000 and 10,000 ppm on the activity of fungal (Aspergillus flavus var. columnaris) alpha-amylase was studied. Indol acetic acid (IAA) and naphthalene acetic acid (NAA) inhibited alpha-amylase activity by 2% and 7% at 1,000 ppm. The other 6 growth regulators, indol butyric acid (IBA), gibberellic acid, cumarin, cycocel (CCC), atonik-G and kylar, did not inhibit but stimulated alpha-amylase activity (0 to 9%) at 1,000 ppm. All growth regulators studied inhibited alpha-amylase activity at 5,000 and 10,000 ppm concentration except kylar. The effect of organic acids and formaldehyde at 0.01, 0.005, and 0.001 M was studied. Acetic acid stimulated alpha-amylase at all concentrations, but formic acid, oxalic acid, lactic acid and citric acid inhibited alpha-amylase activity by 91, 100, 100 and 79%, respectively, at a concentration of 0.01 M, while by 31, 100, 15 and 20%, respectively, at 0.005 M. Formaldehyde induced 7, 3 and 2% inhibition at 0.01, 0.005 and 0.001 M, respectively. At 0.01 M either sorbitol or fructose inhibited alpha-amylase by 8%, Maltose 7%, sucrose 6%, phenol, glucose and galactose each by 5%, ethanol, glycerol, arabinose and sodium benzoate each by 4%, isopropanol and mannitol 1%, but methanol and ammonium citrate dibasic did not inhibit alpha-amylase. The results indicate that CuCl2, SnCl2, AgNO3 and Fe2(SO4)3 were the strongest inhibitors, followed by Cd(C2H3O2), HgCl2, Na2-EDTA, Na2HPO4, and CaCl2 in decreasing order. NaCl, NaBr and Mn SO4 did not inhibit alpha-amylase at concentrations from 10 mM to 0.01 mM. PMID:2515680

  3. Chemical Constituents in Essential Oils from Elsholtzia ciliata and Their Antimicrobial Activities

    TIAN Guang-hui

    2013-01-01

    Objective To compare the chemical constituents in the essential oils from the leaves,flowers,and seeds of Elsholtzia ciliata and their antimicrobial activities.Methods The chemical constituents in essential oils were extracted by the hydro-distillation method and analyzed by GC-MS.The chemical constituents in essential oils were identified on the basis of comparison on their retention indices and MS spectrum with published data.Moreover,the antimicrobial activities of the chemical constituents in the oils against the growth of six bacteria strains and one pathogenic yeast strain were evaluated by using minimum inhibitory concentration and minimum bactericidal concentration methods.Results A total of 58 compounds were identified,while compounds 31,35,and 36 were identified in the essential oils from the leaves,flowers,and seeds,respectively.Fifteen compounds were identified as shared constituents in the leaves,flowers,and seeds.The chemical constituents in the essential oils showed the inhibitory activities against the six bacteria strains and the yeast strain.Conclusion The major constituents are different in the essential oils of the leaves,flowers,and seeds.The major chemical constituents in the essential oils are monoterpenoids and sesquiterpenoids.And the chemical constituents in the essential oils obtained from the leaves show higher inhibitory activities especially against Bacillus subtillis CMCC63501 and Escherichia coli ATCC25922.

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

    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

  5. Extended Functional Groups (EFG: An Efficient Set for Chemical Characterization and Structure-Activity Relationship Studies of Chemical Compounds

    Elena S. Salmina

    2015-12-01

    Full Text Available The article describes a classification system termed “extended functional groups” (EFG, which are an extension of a set previously used by the CheckMol software, that covers in addition heterocyclic compound classes and periodic table groups. The functional groups are defined as SMARTS patterns and are available as part of the ToxAlerts tool (http://ochem.eu/alerts of the On-line CHEmical database and Modeling (OCHEM environment platform. The article describes the motivation and the main ideas behind this extension and demonstrates that EFG can be efficiently used to develop and interpret structure-activity relationship models.

  6. The effects of activation temperature on physico-chemical characteristics of activated carbons derived from biomass wastes

    Sutrisno, Bachrun; Hidayat, Arif

    2015-12-01

    This research focused on investigating in the effect of activation temperature on the physico-chemical properties of palm empty fruit bunch (PEFB) based activated carbon prepared by physical activation with carbon dioxide. The activation temperature was studied in the range of 400-800°C by keeping the activation temperature at 800°C for 120 min. It was found that the porous properties of activated carbon decreased with an increase in carbonization temperature. The activated carbons prepared at the highest activation temperature at 800°C and activation time of 120 min gave the activated carbon with the highest of BET surface area and pore volume of 938 m2/g and 0.4502 cm3/g, respectively

  7. CO2 adsorption on chemically modified activated carbon.

    Caglayan, Burcu Selen; Aksoylu, A Erhan

    2013-05-15

    CO2 adsorption capacity of a commercial activated carbon was improved by using HNO3 oxidation, air oxidation, alkali impregnation and heat treatment under helium gas atmosphere. The surface functional groups produced were investigated by diffuse reflectance infrared Fourier transform spectrometer (DRIFTS). CO2 adsorption capacities of the samples were determined by gravimetric analyses for 25-200°C temperature range. DRIFTS studies revealed the formation of carboxylic acid groups on the HNO3 oxidized adsorbents. Increased aromatization and uniform distribution of the Na particles were observed on the samples prepared by Na2CO3 impregnation onto HNO3 oxidized AC support. The adsorption capacities of the nonimpregnated samples were increased by high temperature helium treatments or by increasing the adsorption temperature; both leading to decomposition of surface oxygen groups, forming sites that can easily adsorb CO2. The adsorption capacity loss due to cyclic adsorption/desorption procedures was overcome with further surface stabilization of Na2CO3 modified samples with high temperature He treatments. With Na2CO3 impregnation the mass uptakes of the adsorbents at 20 bars and 25 °C were improved by 8 and 7 folds and at 1 bar were increased 15 and 16 folds, on the average, compared to their air oxidized and nitric acid oxidized supports, respectively. PMID:23500788

  8. Physico Chemical Properties and Antioxidant Activity of Roselle Seed Extracts

    Abdoulaye Idrissa Cissouma

    2013-11-01

    Full Text Available The aim of this research was to extract phenolic compounds from defatted Roselle (Hibiscus sabdariffaL. seed and assess their antioxidant potential. Water, ethanol (30%, methanol (30% and acetone (30% were used as solvent for extraction. The proximate composition, total phenolic content and extraction yield were analyzed. Antioxidant efficacies of Roselle seed extract were tested by using 1, 1-Diphenyl-2-Picrylhydrazyl (DPPH, hydroxyl, 2, 2’-azinobis-3-ethylbenzothiaz oline-6-sulfonic acid (ABTS radicals scavenging capacities and reducing power analysis. Roselle seeds were found to be rich in protein (27.745%, carbohydrates (40.45% and oil (20.83%. The total phenolic content ranged from 1.66±0.03 to 1.99±0.01 (GAE mg/g using water and 30% acetone respectively. The highest inhibitory capacity on DPPH and ABTS radicals was observed in 30% acetone extract and was at 3 mg/mL for DPPH and 6 mg/mL for ABTS respectively. Ethanol extract showed the highest hydroxyl radical scavenging ability value of 66.36 at 20 mg/mL, followed by methanol (57.27, acetone (56.36 and water (30. The reducing potential of the different extracts was concentration dependent and increased with increase in concentration. These results indicate that substantial antioxidant activity can be obtained from Roselle seed phenolic compounds extract by using 30% acetone.

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

    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. PMID:27311502

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

    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.

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

    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

  12. "SimChemistry" as an Active Learning Tool in Chemical Education

    Bolton, Kim; Saalman, Elisabeth; Christie, Michael; Ingerman, Ake; Linder, Cedric

    2008-01-01

    The publicly available free computer program, "SimChemistry," was used as an active learning tool in the chemical engineering curriculum at the University College of Boras, Sweden. The activity involved students writing their own simulation programs on topics in the area of molecular structure and interactions. Evaluation of the learning…

  13. Investigation of the chemical composition-antibacterial activity relationship of essential oils by chemometric methods.

    Miladinović, Dragoljub L; Ilić, Budimir S; Mihajilov-Krstev, Tatjana M; Nikolić, Nikola D; Miladinović, Ljiljana C; Cvetković, Olga G

    2012-05-01

    The antibacterial effects of Thymus vulgaris (Lamiaceae), Lavandula angustifolia (Lamiaceae), and Calamintha nepeta (Lamiaceae) Savi subsp. nepeta var. subisodonda (Borb.) Hayek essential oils on five different bacteria were estimated. Laboratory control strain and clinical isolates from different pathogenic media were researched by broth microdilution method, with an emphasis on a chemical composition-antibacterial activity relationship. The main constituents of thyme oil were thymol (59.95%) and p-cymene (18.34%). Linalool acetate (38.23%) and β-linalool (35.01%) were main compounds in lavender oil. C. nepeta essential oil was characterized by a high percentage of piperitone oxide (59.07%) and limonene (9.05%). Essential oils have been found to have antimicrobial activity against all tested microorganisms. Classification and comparison of essential oils on the basis of their chemical composition and antibacterial activity were made by utilization of appropriate chemometric methods. The chemical principal component analysis (PCA) and hierachical cluster analysis (HCA) separated essential oils into two groups and two sub-groups. Thyme essential oil forms separate chemical HCA group and exhibits highest antibacterial activity, similar to tetracycline. Essential oils of lavender and C. nepeta in the same chemical HCA group were classified in different groups, within antibacterial PCA and HCA analyses. Lavender oil exhibits higher antibacterial ability in comparison with C. nepeta essential oil, probably based on the concept of synergistic activity of essential oil components. PMID:22389175

  14. Chemical composition and antioxidant activities of Jeddah corniche algae, Saudi Arabia

    Al-Amoudi, Omar A.; Mutawie, Hawazin H.; Patel, Asmita V.; Blunden, Gerald

    2009-01-01

    The increased use of natural product in the pharmaceutical industry has led to an increase in demand for screening for bioactive compounds in marine algae. An important economic algae, through chemical composition analysis and their antioxidant activities were investigated in this study. Chemical composition analysis of three algal samples from the Chlorophyta Ulva lactuca (U), Phaeophyta Sargassum crassifolia (S) and Rhodophyta Digenea simplex (D) was tested. Main components were sugars (57....

  15. Chemical Composition, Antimicrobial and Antioxidant Activities of Hyssop (Hyssopus officinalis L.) Essential Oil

    KIZIL, Süleyman; HAŞİMİ, Nesrin; TOLAN, Veysel; Ersin KILININÇ; Karataş, Hakan

    2010-01-01

    The essential oil of hyssop is widely used in food, pharmaceutical and cosmetic industries throughout the world. Therefore, it is very important to know the chemical characteristics of the oil for economic use and enhanced performance of the end products. This study was carried out to determine antimicrobial and antioxidant activities of the essential oil of Hyssopus officinalis (L.) (Lamiaceae) collected from wild in the Southeast Anatolian, Turkey. Chemical compositions of hydrodistilled es...

  16. Metal Oxide Nanoparticle Growth on Graphene via Chemical Activation with Atomic Oxygen

    Johns, James E.; Alaboson, Justice M. P.; Patwardhan, Sameer; Ryder, Christopher R.; Schatz, George C.; Hersam, Mark C.

    2013-01-01

    Chemically interfacing the inert basal plane of graphene with other materials has limited the development of graphene-based catalysts, composite materials, and devices. Here, we overcome this limitation by chemically activating epitaxial graphene on SiC(0001) using atomic oxygen. Atomic oxygen produces epoxide groups on graphene, which act as reactive nucleation sites for zinc oxide nanoparticle growth using the atomic layer deposition precursor diethyl zinc. In particular, exposure of epoxid...

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

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

    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)

  19. Effect of various chemicals on the aldehyde dehydrogenase activity of the rat liver cytosol.

    Marselos, M; Vasiliou, V

    1991-01-01

    The cytosolic activity of aldehyde dehydrogenase (ALDH) was studied in the rat liver, after acute administration of various carcinogenic and chemically related compounds. Male Wistar rats were treated with 27 different chemicals, including polycyclic aromatic hydrocarbons, aromatic amines, nitrosamines, azo dyes, as well as with some known direct-acting carcinogens. The cytosolic ALDH activity of the liver was determined either with propionaldehyde and NAD (P/NAD), or with benzaldehyde and NADP (B/NADP). The activity of ALDH remained unaffected after treatment with 1-naphthylamine, nitrosamines and also with the direct-acting chemical carcinogens tested. On the contrary, polycyclic aromatic hydrocarbons, polychlorinated biphenyls (Arochlor 1254) and 2-naphthylamine produced a remarkable increase of ALDH. In general, the response to the effectors was disproportionate between the two types of enzyme activity, being much in favour for the B/NADP activity. This fact resulted to an inversion of the ratio B/NADP vs. P/NAD, which under constitutive conditions is lower than 1. In this respect, the most potent compounds were found to be polychlorinated biphenyls, 3-methylcholanthrene, benzo(a)pyrene and 1,2,5,6-dibenzoanthracene. Our results suggest that the B/NADP activity of the soluble ALDH is greatly induced after treatment with compounds possessing aromatic ring(s) in their molecule. It is not known, if this response of the hepatocytes is related with the process of chemical carcinogenesis. PMID:2060039

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

    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. PMID:25686854

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

    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

  2. Advances in Methane Activation Studies at Dalian Institute of Chemical Physics

    2008-01-01

    @@ Following successful implementation of selective oxida-tion of methane into methanol at low temperature (80℃) through setting up a circulating system of multiple electron pairs the Dalian Institute of Chemical Physics (DICP) has made new stride in the fundamental research on direct acti-vation of methane. This institute by means of collaboration with the US West Pacific National Laboratory has acquired the complete information on the structure of active centers of solid catalysts with the relevant results published in the latest issue of Journal of American Chemical Society.

  3. Study on the chemical species of platinum group elements in geological samples by molecular activation analysis

    The chemical species of platinum group elements in some upper mantle-derived xenoliths from Eastern China are studied by molecular activation analysis, in which the chemical stepwise dissolution, nickel fire assay preconcentration and neutron activation analysis are jointly applied. The weighted sums of platinum group elements in 6 phases are in agreement with their total contents. The distribution patterns of platinum group elements in sulphides show that sulphide segregation is one of the important mechanisms for the fractionation of platinum group elements in upper mantle-derived material during partial melting

  4. Screening chemicals for thyroid-disrupting activity: A critical comparison of mammalian and amphibian models.

    Pickford, Daniel B

    2010-11-01

    In order to minimize risks to human and environmental health, chemical safety assessment programs are being reinforced with toxicity tests more specifically designed for detecting endocrine disrupters. This includes the necessity to detect thyroid-disrupting chemicals, which may operate through a variety of modes of action, and have potential to impair neurological development in humans, with resulting deficits of individual and social potential. Mindful of these concerns, the consensus favors in vivo models for both hazard characterization (testing) and hazard identification (screening) steps, in order to minimize false negatives. Owing to its obligate dependence on thyroid hormones, it has been proposed that amphibian metamorphosis be used as a generalized vertebrate model for thyroid function in screening batteries for detection of thyroid disrupters. However, it seems unlikely that such an assay would ever fully replace in vivo mammalian assays currently being validated for human health risk assessment: in its current form the amphibian metamorphosis screening assay would not provide capacity for reliably detecting other modes of endocrine-disrupting activity. Conversely, several candidate mammalian screening assays appear to offer robust capacity to detect a variety of modes of endocrine-disrupting activity, including thyroid activity. To assess whether omission of an amphibian metamorphosis assay from an in vivo screening battery would generate false negatives, the response of amphibian and mammalian assays to a variety known thyroid disrupters, as reported in peer-reviewed literature or government agency reports, was critically reviewed. Of the chemicals investigated from the literature selected (41), more had been tested in mammalian studies with thyroid-relevant endpoints (32) than in amphibian assays with appropriate windows of exposure and developmental endpoints (27). One chemical (methoxychlor) was reported to exhibit thyroid activity in an appropriate

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

    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.

  6. Chemical constituents and antibacterial activity of the leaf essential oil of Feronia limonia

    Kumar, A. Senthil; V. Venkatesalu; Kannathasan, K.; Chandrasekaran, M.

    2010-01-01

    The essential oil from the leaves of Feronia limonia was extracted and the chemical constituents and antibacterial activity were studied. The GC and GC-MS analyses revealed that the leaf essential oil of F. limonia contained fourteen compounds representing about 98.4% of the total oil. The major chemical compounds identified were Eudesma-4 (14).11-dine (46.3%), carvacrol (29.6%) and 1,5-cyclodecandine (13.4%). The essential oil was screened for its antibacterial activity against different cli...

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

    Tahir, D.; Halide, H.; Wahab, A. W.; Kurniawan, D.

    2014-09-01

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

    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.

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

    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. - Highlights: • The gamma irradiation treatment reduces lipoxygenases activity of soybean. • Independently of soybean cultivar, treatment 10 kGy exhibited higher percentages of reduction of lipoxygenase. • Gamma irradiation interfered few in the chemical composition of soybean. • The lipid and protein content remained stable regardless of radiation dose applied to the soybean

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

    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

  11. Identification of chemical modulators of the constitutive activated receptor (CAR) in a gene expression compendium

    Oshida, Keiyu; Vasani, Naresh; Jones, Carlton; Moore, Tanya; Hester, Susan; Nesnow, Stephen; Auerbach, Scott; Geter, David R.; Aleksunes, Lauren M.; Thomas, Russell S.; Applegate, Dawn; Klaassen, Curtis D.; Corton, J. Christopher

    2015-01-01

    The nuclear receptor family member constitutive activated receptor (CAR) is activated by structurally diverse drugs and environmentally-relevant chemicals leading to transcriptional regulation of genes involved in xenobiotic metabolism and transport. Chronic activation of CAR increases liver cancer incidence in rodents, whereas suppression of CAR can lead to steatosis and insulin insensitivity. Here, analytical methods were developed to screen for chemical treatments in a gene expression compendium that lead to alteration of CAR activity. A gene expression biomarker signature of 83 CAR-dependent genes was identified using microarray profiles from the livers of wild-type and CAR-null mice after exposure to three structurally-diverse CAR activators (CITCO, phenobarbital, TCPOBOP). A rank-based algorithm (Running Fisher’s algorithm (p-value ≤ 10-4)) was used to evaluate the similarity between the CAR biomarker signature and a test set of 28 and 32 comparisons positive or negative, respectively, for CAR activation; the test resulted in a balanced accuracy of 97%. The biomarker signature was used to identify chemicals that activate or suppress CAR in an annotated mouse liver/primary hepatocyte gene expression database of ~1850 comparisons. CAR was activated by 1) activators of the aryl hydrocarbon receptor (AhR) in wild-type but not AhR-null mice, 2) pregnane X receptor (PXR) activators in wild-type and to lesser extents in PXR-null mice, and 3) activators of PPARα in wild-type and PPARα-null mice. CAR was consistently activated by five conazole fungicides and four perfluorinated compounds. Comparison of effects in wild-type and CAR-null mice showed that the fungicide propiconazole increased liver weight and hepatocyte proliferation in a CAR-dependent manner, whereas the perfluorinated compound perfluorooctanoic acid (PFOA) increased these endpoints in a CAR-independent manner. A number of compounds suppressed CAR coincident with increases in markers of

  12. Chemical composition and antibacterial activity of essential oil and extracts of Citharexylum spinosum flowers from Thailand.

    Mar, Ae; Pripdeevech, Patcharee

    2014-05-01

    The chemical composition and antibacterial and antioxidant activities of the essential oil and various solvent extracts of Citharexylum spinosum flowers are reported. The chemical compositions were determined by GC-MS with 151 volatile constituents identified. Methyl benzoate, piperitone, maltol, and maple furanone were the major constituents. All extracts were tested for their antibacterial activity against eight microorganisms. The flower oil had the greatest antibacterial activity against all bacterial strains (MIC values of 31.2 microg/mL), while the other solvent extracts had MIC values ranging from 31.2 to 1000 microg/mL. The essential oil had the highest antioxidant activity and total phenol content with IC50 values of 62.7 and 107.3 microg/mL, respectively. PMID:25026728

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

    Khalifa E Sharquie; Adil A Noaimi; Entesar A. Al-Janabi

    2014-01-01

    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. ...

  14. Chemical Analysis and Antioxidant Activity in vitro of Polysaccharides Extracted from Lower Grade Green Tea

    Ping Chen; Yongjun Zhang; Liyun Zhu; Hui Jin; Gaofan Zhang; Dongyang Su; Jia Li

    2013-01-01

    Tea is a well-known and important agricultural product in the world. The Crude Polysaccharides from tea leaves (CP) probably have good antioxidant activities. However, whether or not the antioxidant abilities of CP depend on tea polyphenols in the CP is not understanded. In this study, four CP fractions (TPF30, TPF50, TPF70 and TPF90) were isolated from CP and their antioxidant activities were compared. Meanwhile, Chemical and physical characteristics of CP and four CP fractions were investig...

  15. Chemical Composition of Propolis from Different Regions in Java and their Cytotoxic Activity

    Syamsudin; Sudjaswadi Wiryowidagdo; Partomuan Simanjuntak; Wan Lelly Heffen

    2009-01-01

    Problem statement: Propolis samples from tropical zones, such as Java (Indonesia) with its vast biodiversity, have become a subject of increasing scientific and economic attention. The association of the chemical composition of propolis from different geographic regions with cytotoxic activities lead to the identification of active principles, a fundamental tool to achieve standardization of this bee product. Approach: The purpose of this research was evaluate the quality of propolis collecte...

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

    M. Sokovic; 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...

  17. The Dynamics of fluid flow and associated chemical fluxes at active continental margins

    Solomon, Evan Alan

    2007-01-01

    Active fluid flow plays an important role in the geochemical, thermal, and physical evolution of the Earth’s crust. This dissertation investigates the active fluid flow and associated chemical fluxes at two dynamic continental margins: The Costa Rica subduction zone and the northern Gulf of Mexico hydrocarbon province, using novel seafloor instrumentation for continuous monitoring of fluid flow rates and chemistry. Traditional pore fluid sampling methods and flow rate models only provide a ...

  18. Chemical Compositions, Antioxidant and Antimicrobial Activities of Essential Oils of Piper caninum Blume

    Hasnah Mohd Sirat; Khong Heng Yen; Farediah Ahmad; Wan Mohd Nuzul Hakimi Wan Salleh

    2011-01-01

    Chemical composition, antioxidant and antimicrobial activities of the fresh leaves and stems oils of Piper caninum were investigated. A total of forty eight constituents were identified in the leaves (77.9%) and stems (87.0%) oil which were characterized by high proportions of phenylpropanoid, safrole with 17.1% for leaves and 25.5% for stems oil. Antioxidant activities were evaluated by using β-carotene/linoleic acid bleaching, DPPH radical scavenging and total phenolic content. Stems oil sh...

  19. Determination of antibacterial, antifungal activity and chemical composition of essential oil portion of unani formulation kulzam

    K Ashok Kumar; Ram Kumar Choudhary; Bheemachari Joshi; V.Ramya; V Sahithi; Veena, P.

    2011-01-01

    Kulzam is a popular unani, liquid formulation; indicated for several minor ailments like cough, cold, running nose, sore throat, insect bites, earache, tooth ache, etc. by the manufacturer. However, this over the counter formulation has not been scientifically evaluated for its claimed uses. Hence in the present study an attempt has been to check the chemical composition, antibacterial and antifungal activity as most of the above-mentioned conditions are underpinned by microbial activity. The...

  20. Chemical properties population of nitrites oxidizers, urease and phosphatase activities in sewage sludge-amended soils

    Bonmati Pont, Manuel; Pujolà Cunill, Montserrat; Saña Vilaseca, Josep; Soliva Torrentó, Montserrat; Felipó, Ma. Teresa (María Teresa); Garau, M; B. Ceccanti; P. Nannipieri

    1985-01-01

    The aim of this work has been to determine the effect of sterilized and non-sterilized, aerobically or anaerobically digested sewage sludges on urease and phosphatase aetivities, on populations of nitrite oxidizers and on some chemical properties in laboratory conditions and for long incubation periods. Both urease an phosphatase activities were affected when anaerobic sludges were added to the soil. The inhibitory effects on both enzyme activities attributed to the presence of...

  1. Chemical and biological evolution of (U-14C)phenol sorbed on activated carbon

    Methods describing the chemical and biological evolution of (U-14C)phenol adsorbed on activated carbon are given with or without the use of bacteria. Without bacteria, the (U-14C)phenol initially adsorbed is not removed from the carbon after adding a solution of unlabelled phenol through the column for eight days. With bacteria, the (U-14C)phenol initially present, is removed (60-70%) from activated carbon with a solution containing unlabelled phenol, nitrogen and phosphorus. (author)

  2. Chemical Composition, Antimicrobial and Antioxidant Activities of the Volatile Oil of Ganoderma pfeifferi Bres

    Mohamed Al-Fatimi; Martina Wurster; Ulrike Lindequist

    2016-01-01

    In a first study of the volatile oil of the mushroom basidiomycete Ganoderma pfeifferi Bres., the chemical composition and antimicrobial and antioxidant activities of the oil were investigated. The volatile oil was obtained from the fresh fruiting bodies of Ganoderma pfeifferi Bres. By hydrodistillation extraction and analyzed by GC-MS. The antimicrobial activity of the oil was evaluated against five bacteria strains and two types of fungi strains, using disc diffusion and broth microdilution...

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

    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...

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

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

    2012-01-01

    differentiation although PPARγ activation is neither a requirement nor a guarantee for stimulation. Four out of the eleven chemicals (bisphenol A, mono-ethylhexyl phthalate, butylparaben, PCB 153) caused increased adipogenesis. The release of adipocyte-secreted hormones was sometimes but not always correlated...

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

    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

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

    Gringer, Nina; Osman, Ali; Nielsen, Henrik Hauch; Undeland, Ingrid; Baron, Caroline P.

    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...

  7. Chemical composition and biological activity of the essential oil of rhizome of Zingiber zerumbet (L.) smith

    Technical Abstract: The aim was designed to study the biological activity and chemical composition of essential oil of Zingiber zerumbet (L.) Smith. The essential oil extracted from the rhizome of the plant was analysed by gas chromatography-mass spectroscopy and its major components amounting t...

  8. EFFECT OF WATER POLLUTANTS AND OTHER CHEMICALS UPON THE ACTIVITY OF LIPASE 'IN VITRO'

    Lipase preparations were treated in vitro with 100 chemicals of various classes, many of which are environmental pollutants, to determine their effect upon enzyme activity. The greatest inhibition was caused by mercuric ion and certain heavy metal cations; almost as inhibiting we...

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

    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.

  10. TEXTURAL AND CHEMICAL CHARACTERISATION OF ACTIVATED CARBONS PREPARED FROM RICE HUSK (ORYZA SATIVA USING A TWO- STAGE ACTIVATION PROCESS

    JOSEPH G. COLLIN

    2008-12-01

    Full Text Available Activated carbons from agro-industrial wastes; rice husk; were prepared by physical and chemical activation using phosphoric acid as the dehydrating agent. A two-stage activation process method was used; with semi-carbonisation stage at 200oC for 15 minutes as the first stage followed by an activation stage at 500oC for 45 minutes as the second stage. The precursor material with the impregnation agent was exposed straightaway to semi-carbonization and activation temperature unlike the specific temperature progression as reported in the literature. All experiments were conducted in a laboratory scale muffle furnace under static conditions in a self generated atmosphere covering process parameters such as impregnation ratios. We found that by using this method, the AC5 had the highest iodine number and methylene blue adsorption capacity which was 506.6 mg/g and 319.0 mg/g respectively.

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

    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.

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

    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. PMID:24650181

  13. Chemically active colloids near osmotic-responsive walls with surface-chemistry gradients

    Popescu, M N; Dietrich, S

    2016-01-01

    Chemically active colloids move by creating gradients in the composition of the surrounding solution and by exploiting the differences in their interactions with the various molecular species in solution. If such particles move near boundaries, e.g., the walls of the container confining the suspension, gradients in the composition of the solution are also created along the wall. This give rise to chemi-osmosis (via the interactions of the wall with the molecular species forming the solution), which drives flows coupling back to the colloid and thus influences its motility. Employing an approximate "point-particle" analysis, we show analytically that -- owing to this kind of induced active response (chemi-osmosis) of the wall -- such chemically active colloids can align with, and follow, gradients in the surface chemistry of the wall. In this sense, these artificial "swimmers" exhibit a primitive form of thigmotaxis with the meaning of sensing the proximity of a (not necessarily discontinuous) physical change ...

  14. Aerobic Damage to [FeFe]-Hydrogenases: Activation Barriers for the Chemical Attachment of O2**

    Kubas, Adam; De Sancho, David; Best, Robert B; Blumberger, Jochen

    2014-01-01

    [FeFe]-hydrogenases are the best natural hydrogen-producing enzymes but their biotechnological exploitation is hampered by their extreme oxygen sensitivity. The free energy profile for the chemical attachment of O2 to the enzyme active site was investigated by using a range-separated density functional re-parametrized to reproduce high-level ab initio data. An activation free-energy barrier of 13 kcal mol−1 was obtained for chemical bond formation between the di-iron active site and O2, a value in good agreement with experimental inactivation rates. The oxygen binding can be viewed as an inner-sphere electron-transfer process that is strongly influenced by Coulombic interactions with the proximal cubane cluster and the protein environment. The implications of these results for future mutation studies with the aim of increasing the oxygen tolerance of this enzyme are discussed. PMID:24615978

  15. Chemical composition and antimicrobial activity of the essential oil from leaves of Algerian Melissa officinalis L.

    Abdellatif, Fahima; Boudjella, Hadjira; Zitouni, Abdelghani; Hassani, Aicha

    2014-01-01

    The essential oil obtained from leaves of Melissa officinalis L. (Family of Lamiaceae) growing in Algeria, was investigated for its chemical composition and in vitro antimicrobial activity. The chemical composition was determined by hydro-distillation and analyzed by GC/MS and GC-FID. Sixty-three compounds were identified in the essential oil, representing 94.10 % of the total oil and the yields were 0.34 %. The major component was geranial (44.20 %). Other predominant components were neral (...

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

    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

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

    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.

  18. Chemical composition of the volatile oil from Zanthoxylum avicennae and antimicrobial activities and cytotoxicity

    Yin Lin

    2014-01-01

    Full Text Available Background: Through literature retrieval, there has been no report on the research of the chemical components in Zanthoxylum avicennae (Lam. DC. This paper extracted and determined the chemical components of the volatile oil in Z. avicennae, and at the same time, measured and evaluated the bioactivity of the volatile oil in Z. avicennae. Materials and Methods: We extract the volatile oil in Z. avicennae by steam distillation method, determined the chemical composition of the volatile oil by GC-MS coupling technique, and adopt the peak area normalization method to measured the relative percentage of each chemical composition in the volatile oil. Meanwhile, we use the Lethal-to-prawn larva bioactivity experiment to screen the cytotoxicity activities of the volatile oil in Z. avicennae, and using the slanting test-tube experiment to determine and evaluate its antibacterial activities in vitro for the eight kinds of plant pathogenic fungi in the volatile oil of the Z. avicennae. Results: The results show that 68 kinds of compounds are determined from the volatile oil of Z. avicennae. The determined part takes up 97.89% of the total peak area. The main ingredients in the volatile oil of Z. avicennae are sesquiterpenoids and monoterpene. The test results show that the volatile oil in Z. avicennae has strong antibacterial activities and cytotoxicity, with the strongest antibacterial activity against the Rhizoctonia solani AG1-1A. Conclusion: This research results will provide reference data for understanding the chemical composition of the volatile oil in the aromatic plant of Z. avicennae and its bioactivity, and for its further development and application.

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

    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 m2 g-1, 1038.78 m2 g-1 and 0.375 m3 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 m2/g. → Monolayer adsorption capacity of PSAC for MB was 296.57 mg/g.

  20. Activated Carbons From Grape Seeds By Chemical Activation With Potassium Carbonate And Potassium Hydroxide

    Okman, Irem; Karagöz, Selhan; Tay, Turgay; Erdem, Murat

    2014-02-01

    Activated carbons were produced from grape seed using either potassium carbonate (K2CO3) or potassium hydroxide (KOH). The carbonization experiments were accomplished at 600 and 800 °C. The effects of the experimental conditions (i.e., type of activation reagents, reagent concentrations, and carbonization temperatures) on the yields and the properties of these activated carbons were analyzed under identical conditions. An increase in the temperature at the same concentrations for both K2CO3 and KOH led to a decrease in the yields of the activated carbons. The lowest activated carbon yields were obtained at 800 °C at the highest reagent concentration (100 wt%) for both K2CO3 and KOH. The activated carbon with the highest surface area of 1238 m2g-1 was obtained at 800 °C in K2CO3 concentration of 50 wt% while KOH produced the activated carbon with the highest surface area of 1222 m2g-1 in a concentration of 25wt% at 800 °C. The obtained activated carbons were mainly microporous.

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

    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.

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

    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. PMID:27344951

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

    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 %.

  4. Chemical modification and antioxidant activities of polysaccharide from mushroom Inonotus obliquus.

    Ma, Lishuai; Chen, Haixia; Zhang, Yu; Zhang, Ning; Fu, Lingling

    2012-06-20

    Chemical modification polysaccharides exerted potent biological property which was related to the physicochemical properties. In the present study, polysaccharides from Inonotus obliquus were modified by suflation, acetylation and carboxymethylation. The physicochemical and antioxidant properties of I. obliquus polysaccharide (IOPS) and its derivatives were comparatively investigated by chemical methods, gas chromatography, size exclusion chromatography, scanning electron micrograph, infrared spectra and circular dichroism spectra, and ferric reducing power assay and lipid peroxidation inhibition assay, respectively. Results showed that physicochemical and antioxidant properties of IOPS were differed each other after the chemical modification of suflation, acetylation and carboxymethylation. Among the three derivatives, acetylationed polysaccharide (Ac-IOPS) resulted in lower molecular weight distribution, lower intrinsic viscosity, a hyperbranched conformation, higher antioxidant abilities on ferric-reducing power and lipid peroxidation inhibition activity compared with the native polysaccharide IOPS. Ac-IOPS might be explored as a novel potential antioxidant for human consumption. PMID:24750732

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

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

    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.

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

    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.

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

    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 Composition, Antimicrobial and Antioxidant Activities of Hyssop (Hyssopus officinalis L. Essential Oil

    Süleyman KIZIL

    2010-12-01

    Full Text Available The essential oil of hyssop is widely used in food, pharmaceutical and cosmetic industries throughout the world. Therefore, it is very important to know the chemical characteristics of the oil for economic use and enhanced performance of the end products. This study was carried out to determine antimicrobial and antioxidant activities of the essential oil of Hyssopus officinalis (L. (Lamiaceae collected from wild in the Southeast Anatolian, Turkey. Chemical compositions of hydrodistilled essential oils obtained from hyssop leaves were analyzed by gas chromatography-mass spectrometry (GC-MS. For antimicrobial activity, disc diffusion tests were carried out on Escherichia coli line ATCC25922, Pseudomonas aeroginosa line ATCC27853, Staphylococcus aureus line 25923, Staphylococcus pyogenes line ATCC19615 and Candida albicans line ATCC10231, and the antioxidant activity was determined by using the diphenylpicrylhydrazyl (DPPH radical-scavenging method. It was determined that hyssop essential oil contained isopinocamphone (57.27%, (--?-pinene (7.23%, (--terpinen-4-ol (7.13%, pinocarvone (6.49%, carvacrol (3.02%, p-cymene (2.81% and myrtenal (2.32% as major components. As shown by treatments with 5 and 10 ?l of oil; which exhibited strong antimicrobial activity against S. pyogenes, S. aureus, C. albicans and E. coli, but not against P. aeruginosa. The antioxidant activity of H. officinalis essential oil was lower compared to butylated hydroxytoluene (BHT and ascorbic acid. These results demonstrated that hyssop essential oil has relatively low antioxidant activity and good antimicrobial activity against some test organisms.

  10. Chemical Analysis and Antioxidant Activity in vitro of Polysaccharides Extracted from Lower Grade Green Tea

    Ping Chen

    2013-10-01

    Full Text Available Tea is a well-known and important agricultural product in the world. The Crude Polysaccharides from tea leaves (CP probably have good antioxidant activities. However, whether or not the antioxidant abilities of CP depend on tea polyphenols in the CP is not understanded. In this study, four CP fractions (TPF30, TPF50, TPF70 and TPF90 were isolated from CP and their antioxidant activities were compared. Meanwhile, Chemical and physical characteristics of CP and four CP fractions were investigated by the combination of chemical and instrumental analysis methods. Their antioxidant activities were investigated in vitro systems, including hydroxyl radical assay, 1, 1-Diphenyl-2-Picrylhydrazyl (DPPH• scavenging activity, reducing power and chelating activity. Among CP and these four polysaccharides, TPF90 showed more significant DPPH• scavenging activity and highest reducing power, chelating activity and inhibitory effects on hydroxyl radical. Thus, it can be concluded that polysaccharides extracted from the lower grade green tea might be employed as ingredients in healthy and functional food to alleviate the oxidative stress.

  11. Chemical constituents and anti-tuberculosis activity of ink extracts of cuttlefish, Sepiella inermis

    Muthusamy Ravichandiran

    2013-11-01

    Full Text Available Objective: To study the chemical constituents and the anti-tuberculosis activity of methanol and chloroform ink extracts of Sepiella inermis. Methods: Pulverized ink powder was extracted separately with chloroform and methanol. Chemical analysis was carried out by UV-VIS spectrophotometer, FT-IR and GC-MS. Crude extracts were tested in vitro for their activity against Mycobacterium tuberculosis using Lowenstein Jensen (L-J medium. Activity in L-J medium was assessed by mean reduction in number of colonies on extract containing bottles as compared to extract free controls. Results: GC-MS of methanol extract revealed four compounds viz. hexadecanoic acid, 9, 12- octadecadienoic acid, 9-octadecenoic acid and octadecanoic acid. The chloroform extract containing fourteen compounds. The methanol extract exhibited anti-tuberculosis activity in L-J medium at 64 µg/mL with the observed inhibition of 14 CFU. Chloroform extract displayed a weak activity against Mycobacterium tuberculosis. Conclusions: This investigation showed the methanol extract exhibited significant activity against Mycobacterium tuberculosis than chloroform extract. Since ink of sepia is available abundantly as a waste material, further studies aimed at isolation and efficacy of active substances pave the way for new anti-tuberculosis drugs.

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

    Putz, Mihai V.; Duda-Seiman, Corina; Duda-Seiman, Daniel; Putz, Ana-Maria; Alexandrescu, Iulia; Mernea, Maria; Avram, Speranta

    2016-01-01

    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-(phenylthio)thymine 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. PMID:27399692

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

    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.

  14. Chemical Structure-Biological Activity Models for Pharmacophores' 3D-Interactions.

    Putz, Mihai V; Duda-Seiman, Corina; Duda-Seiman, Daniel; Putz, Ana-Maria; Alexandrescu, Iulia; Mernea, Maria; Avram, Speranta

    2016-01-01

    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-(phenylthio)thymine 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. PMID:27399692

  15. [Salt resistance and its mechanism of cucumber under effects of exogenous chemical activators].

    Song, Shiqing; Liu, Wei; Guo, Shirong; Shang, Qingmao; Zhang, Zhigang

    2006-10-01

    With root injection and foliar spray, this paper studied the effects of different concentrations salicylic acid, brassinolide, chitosan and spermidine on the growth, morphogenesis, and physiological and biochemical characters of cucumber ( Cucumis sativus L. ) seedlings under 200 mmol x L(-1) NaCl stress. The results showed that at proper concentrations, these four exogenous chemical activators could markedly decrease the salt stress index and mortality of cucumber seedlings, and the decrement induced by 0. 01 mg x L (-1) brassinolide was the largest, being 63. 0% and 75. 0% , respectively. The activities of superoxide dismutase (SOD) , peroxidase (POD) and catalase (CAT) increased significantly, resulting in a marked decrease of malondialdehyde (MDA) content and electrolyte leakage. The dry weight water content and morphogenesis of cucumber seedlings improved, and the stem diameter, leaf number, and healthy index increased significantly. All of these suggested that exogenous chemical activators at proper concentrations could induce the salt resistance of cucumber, and mitigate the damage degree of salt stress. The salt resistance effect of test exogenous chemical activators decreased in the sequence of 0.005 -0.05 mg (L-1) brassinolide, 150 -250 mg x L (-1) spermidine, 100 -200 mg x L(-1) chitosan, and 50 -150 mg x L(-1) salicylic acid. PMID:17209385

  16. Chemical composition, antimicrobial activity and antiviral activity of essential oil of Carum copticum from Iran

    Reza Kazemi Oskuee; Javad Behravan; Mohammad Ramezani

    2011-01-01

    Objectives: Evaluation of therapeutic effects of Carum copticum (C. copticum) has been the subject of several studies in recent years. Thymol the major component of C. copticum is a widely known anti-microbial agent. In this study, the antibacterial and anti viral activities of essential oil of C. copticum fruit were determined. Materials and Methods: Essential oil of C. copticum was analyzed by means of gas chromatography-mass spectrometry (GC-MS). The antimicrobial activity of the oil wa...

  17. Immobilization of chemically modified horse radish peroxidase within activated alginate beads

    Spasojević Dragica

    2014-01-01

    Full Text Available Immobilization of horse radish peroxidase (HRP within alginate beads was improved by chemical modification of the enzyme and polysaccharide chains. HRP and alginate were oxidized by periodate and subsequently modified with ethylenediamine. Highest specific activity of 0.43 U/ml of gel and 81 % of bound enzyme activity was obtained using aminated HRP and alginate oxidized by periodate. Immobilized enzyme retained 75 % of original activity after 2 days of incubation in 80 % (v/v dioxane and had increased activity at basic pH values compared to native enzyme. During repeated use in batch reactor for pyrogallol oxidation immobilized peroxidase retained 75 % of original activity. [Projekat Ministarstva nauke Republike Srbije, br. ON173017 i br. ON172049

  18. Chemical Constituents and Antimicrobial Activity of Indian Green Leafy Vegetable Cardiospermum halicacabum.

    Jeyadevi, R; Sivasudha, T; Ilavarasi, A; Thajuddin, N

    2013-06-01

    The present study was carried out to analyze chemical constituents and antibacterial activity of ethanolic leaf extract of Cardiospermum halicacabum (ECH). The FT-IR spectrum confirmed the presence of alcohols, phenols, alkanes, alkynes, aliphatic ester and flavonoids in ECH. The GC-MS analysis revealed that ECH contained about twenty four compounds. The major chemical compounds identified were cyclohexane-1, 4, 5-triol-3-one-1-carboxylic acid, benzene acetic acid, caryophyllene, phytol and neophytadiene. The ECH was screened for its antibacterial activity against different bacterial strains and anti fungal activity against Candida albicans by agar well diffusion and minimum inhibitory concentration (MIC) assay. ECH exhibited antibacterial and antifungal activity. All the tested bacterial strains showed MIC values ranging from 80 to 125 μg of extract/ml and C. albicans showed 190 μg of extract/ml as a MIC. The maximum activity ECH was observed against human pathogen Staphylococcus aureus followed by Escherichia coli and the fish pathogen Aeromonas hydrophila. ECH exhibited moderate activity against some of the tested multidrug resistant strains. PMID:24426110

  19. Preparation of activated carbon from acacia arabica by chemical activation for possible use in the treatment of chemical activation for possible use in the treatment of textile effluents

    Wood of Acacia Arabica syn. A. Nilotica, a locally available tree was used for the preparation of porous activated carbon for adsorption of dyes from aqueous solutions. The broken pieces of wood (6-10 mm size) were semicarbonized at 350 degree C in an atmosphere of N/sub 2/ gas and then impregnated with varying concentration of ZnCl/sub 2/ solution. The dried samples were sieved and carbonized under nitrogen atmosphere at various temperatures for activation. The porosity of the resulting carbon increased with the carbonization temperature to a maximum and then started decreasing with further increase in temperature. The optimum conditions for the production of activated carbon from kikar wood were observed to be carbonization temperature of 700 degree C for one hour with impregnation of wood to ZnCl/sub 2/ ratio of 1:2.5. The prepared activated carbon was evaluated with standard test methods and found to have high active surface area (Maximum Iodine No. 890). The possible industrial utility of the produced activated carbon was examined by adsorption of Congo red dye from its solutions. Different parameters including agitation time, adsorbent dose and temperature of adsorption were studied for finding the optimum conditions for maximum adsorption of the dye. Maximum removal of the dye (99%) was observed at 80 degree C with agitation time of 30min and activated carbon dose of 0.5g/100 ml solution for an initial concentrations of 100 mg/l of the dye. (author)

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

    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. PMID:27536531

  1. Catalytic activity of platinum on ruthenium electrodes with modified (electro)chemical states.

    Park, Kyung-Won; Sung, Yung-Eun

    2005-07-21

    Using Pt on Ru thin-film electrodes with various (electro)chemical states designed by the sputtering method, the effect of Ru states on the catalytic activity of Pt was investigated. The chemical and electrochemical properties of Pt/Ru thin-film samples were confirmed by X-ray photoelectron spectroscopy (XPS) and cyclic voltammetry. In addition, Pt nanoparticles on Ru metal or oxide for an actual fuel cell system showed an effect of Ru states on the catalytic activity of Pt in methanol electrooxidation. Finally, it was concluded that such an enhancement of methanol electrooxidation on the Pt is responsible for Ru metallic and/or oxidation sites compared to pure Pt without any Ru state. PMID:16852701

  2. Can clouds enhance long-range transport of low volatile, ionizable and surface-active chemicals?

    Franco, Antonio; Trapp, Stefan

    2011-01-01

    potential of non-volatile substances. The liquid water content of clouds and the high specific surface of frozen or liquid cloud droplets can significantly contribute to the total activity capacity (i.e. the capacity to sorb chemicals) of the atmosphere for non-volatile, ionizable and surface active...... volatile or ionizable chemicals to investigate the potential of clouds to enhance the atmospheric transport potential. Probability density functions were derived for input substance properties and environmental parameters to quantify uncertainty and variability and probabilistic simulations at steady state...... were run for a constant emission to the atmospheric boundary layer to identify key model inputs. The degradation rate, the duration of dry and wet periods and the parameters describing air-water bulk partitioning (KAW and T) and ionization (pKa and pH) determine the residence time in the ABL. In the...

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

    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. Adaptive Neuro-Fuzzy Inference System Applied QSAR with Quantum Chemical Descriptors for Predicting Radical Scavenging Activities of Carotenoids

    Changho Jhin; Keum Taek Hwang

    2015-01-01

    One of the physiological characteristics of carotenoids is their radical scavenging activity. In this study, the relationship between radical scavenging activities and quantum chemical descriptors of carotenoids was determined. Adaptive neuro-fuzzy inference system (ANFIS) applied quantitative structure-activity relationship models (QSAR) were also developed for predicting and comparing radical scavenging activities of carotenoids. Semi-empirical PM6 and PM7 quantum chemical calculations were...

  5. Preparation and characterization of activated carbon from reedy grass leaves by chemical activation with H3PO4

    Highlights: • Activated carbons were produced from reedy grass leaves by activation with phosphoric acid. • The activated carbons have a large number of oxygen- and phosphorus-containing surface groups. • The structure of activated carbons was bight fibers features on the surface and the external surface of the activated carbons was slightly corrugated and abundant pores. - Abstract: Activated carbons were produced from reedy grass leaves by chemical activation with H3PO4 in N2 atmosphere and their characteristics were investigated. The effects of activation temperature and time were examined. Adsorption capacity was demonstrated with BET and iodine number. Micropore volume and pore size distribution of activated carbons were characterized by N2 adsorption isotherms. The surface area and iodine number of the activated carbons produced at 500 °C for 2 h were 1474 m2/g and 1128 mg/g, respectively. Thermal decomposition of pure reedy grass leaves and H3PO4-impregnated reedy grass leaves have been investigated with thermogravimetric/mass spectroscopy (TG–MS) technique. It was found that the temperature and intensity of maximum evolution of H2O and CO2 of H3PO4-impregnated reedy grass leaves were lower than that of pure reedy grass leaves. This implies that H3PO4 as an activating reagent changed the thermal degradation of the reedy grass leaves, stabilized the cellulose structure, leading to a subsequent change in the evolution of porosity. The results of X-ray photoelectron spectroscopy and Fourier-infrared spectroscopy analysis indicate that the produced activated carbons have rich functional groups on surface

  6. Chemical constituents of Phragmanthera austroarabica A. G. Mill and J. A. Nyberg with potent antioxidant activity

    Jihan M. Badr

    2015-01-01

    Background: Phragmanthera austroarabica A.G. Mill. and J. A. Nyberg is a semi parasitic plant belonging to family Loranthaceae. It was collected from Saudi Arabia. It is widely used in folk medicine among the kingdom in treatment of various diseases including diabetes mellitus. Objective: The total alcoholic extract of P. austroarabica collected from Saudi Arabia was investigated for the chemical structure and prominent biological activity of the main constituents. Materials and Methods: Isol...

  7. A Soil-free System for Assaying Nematicidal Activity of Chemicals

    Preiser, F. A.; Babu, J. R.; Haidri, A. A.

    1981-01-01

    A biological assay system for studying the nematicidal activity of chemicals has been devised using a model consisting of cucumber (Cucumis sativus L. cv. Long Marketer) seedlings growing in the diSPo® growth-pouch apparatus. Meloidogyne incognita was used as the test organism. The response was quantified in terms of the numbers of galls produced. Statistical procedures were applied to estimate the ED50 values of currently available nematicides. This system permits accurate quantification of ...

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

    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.

  9. Neurodevelopmental toxicity of prenatal polychlorinated biphenyls (PCBs) by chemical structure and activity: a birth cohort study

    Park Hye-Youn; Hertz-Picciotto Irva; Sovcikova Eva; Kocan Anton; Drobna Beata; Trnovec Tomas

    2010-01-01

    Abstract Background Polychlorinated biphenyls (PCBs) are ubiquitous environmental toxins. Although there is growing evidence to support an association between PCBs and deficits of neurodevelopment, the specific mechanisms are not well understood. The potentially different roles of specific PCB groups defined by chemical structures or hormonal activities e.g., dioxin-like, non-dioxin like, or anti-estrogenic PCBs, remain unclear. Our objective was to examine the association between prenatal ex...

  10. The Polyphenols Stability, Enzyme Activity and Physico-Chemical Parameters During Producing Wild Elderberry Concentrated Juice

    Ante Galić; Verica Dragović-uzelac; Branka Levaj; Danijela Bursać Kovačević; Stjepan Pliestić; Sabina Arnautović

    2009-01-01

    The influence of processing wild elderberry into concentrated juice on polyphenols (total phenols, flavonoids, non-flavonoids, anthocyanins, flavan-3-ols, hydrolysed tannins) stability, activity of polyphenol oxidase (PPO) and peroxidase (POD), and changes of physico-chemical parameters (total and soluble dry matter, total acidity, pH, sugars) were investigated. The amounts of total phenols, flavonoids, non-flavonoids, falvan-3-ols and hydrolysed tannins were analyzed using Folin-Ciocalteu co...

  11. Global CO2-consumption by chemical weathering: What is the contribution of highly active weathering regions?

    Hartmann, Jens; Jansen, N; Dürr, H. H.; Kempe, S.; Köhler, Peter

    2009-01-01

    CO2-consumption by chemical weathering of silicates and resulting silicate/carbonate weathering ratios influences the terrestrial lateral inorganic carbon flux to the ocean and long-term climate changes. However, little is known of the spatial extension of highly active weathering regions and their proportion of global CO2-consumption. As those regions may be of significant importance for global climate change, global CO2-consumption is calculated here at high resolution, to adequately repres...

  12. Chemical Constituents of the Fruiting Bodies of Clitocybe nebularis and Their Antifungal Activity

    Kim, Young-Sook; Lee, In-Kyoung; Seok, Soon-Ja; Yun, Bong-Sik

    2008-01-01

    During a continuing search for antimicrobial substances from Korean native wild mushroom extracts, we found that the methanolic extract of the fruiting body of Clitocybe nebularis exhibited mild antifungal activity against pathogenic fungi. Therefore we evaluated the antifungal substances and other chemical components of the fruiting body of Clitocybe nebularis, which led to the isolation of nebularine, phenylacetic acid, purine, uridine, adenine, uracil, benzoic acid, and mannitol. Nebularin...

  13. Chemical composition and antifungal activity of essential oil from Eucalyptus smithii against dermatophytes

    Edilene Bolutari Baptista; Danielle Cristina Zimmermann-Franco; Alexandre Augusto Barros Lataliza; Nádia Rezende Barbosa Raposo

    2015-01-01

    ABSTRACT INTRODUCTION: In this study, we evaluated the chemical composition of a commercial sample of essential oil from Eucalyptus smithii R.T. Baker and its antifungal activity against Microsporum canis ATCC 32903, Microsporum gypseum ATCC 14683, Trichophyton mentagrophytes ATCC 9533, T. mentagrophytes ATCC 11480, T. mentagrophytes ATCC 11481, and Trichophyton rubrum CCT 5507. METHODS: Morphological changes in these fungi after treatment with the oil were determined by scanning electron ...

  14. Chemical composition, antioxidant activity and bioaccessibility studies in phenolic extracts of two Hericium wild edible species

    Heleno, Sandrina A.;; Barros, Lillian; Martins, Anabela; Queiroz, Maria João R. P.; Morales, Patricia; Fernández-Ruiz, Virginia; Ferreira, Isabel C. F. R.

    2015-01-01

    Mushrooms are rich sources of bioactive compounds such as phenolic acids. When ingested, these molecules have to be released from the matrix to be transformed/absorbed by the organism, so that they can exert their bioactivity. Several in vitro methodologies have been developed in order to evaluate the bioavailability of bioactive compounds. Herein, two Hericium species were analyzed for their chemical composition and antioxidant activity. Furthermore, an in vitro digestion of the mushrooms an...

  15. Chemical characterization and biological activity of Chaga (Inonotus obliquus), a medicinal “mushroom”

    Glamočlija, Jasmina; Ćirić, Ana; Nikolić, Miloš; Fernandes, Ângela; Barros, Lillian; Ricardo C. Calhelha; Ferreira, Isabel C.F.R.; Soković, Marina; Van Griensven, Leo J. L. D.

    2015-01-01

    Chemical composition and biological properties of aqueous and ethanolic extracts of Inonotus obliquus (Pers.:Fr.) Pilat from different origins, i.e. of Finland, Russia, and Thailand, were studied. Concerning biological activity, antimicrobial, antiqourum, antioxidative, and antitumor and cytotoxic effects were tested. Oxalic acid was found as the main organic acid, with the highest amount in Russian aqueous extract. Gallic, protocatechuic and p-hydroxybenzoic acids were detected in all sample...

  16. Effect of chemical activation of 10% carbamide peroxide gel in tooth bleaching.

    Batista, Graziela Ribeiro; Arantes, Paula Tamiao; Attin, Thomas; Wiegand, Annette; Torres, Carlos Rocha

    2013-01-01

    This study aimed to evaluate the efficacy of chemical agents to increase the bleaching effectiveness of 10% carbamide peroxide. Two hundred and ninety enamel-dentin discs were prepared from bovine incisors. The color measurement was performed by a spectrophotometer using the CIE L*a*b*system. The groups were divided according to the bleaching treatment: negative control group (NC): without bleaching; positive control group (PC): bleached with 10% carbamide peroxide gel without any chemical activator; Manganese gluconate (MG); Manganese chloride (MC); Ferrous gluconate (FG); Ferric chloride (FC); and Ferrous sulphate (FS). Three different concentrations (MG, MC, FG, FC: 0.01, 0.02 and 0.03% w/w; FS: 0.001, 0.002 and 0.003% w/w) for each agent were tested. The bleaching gel was applied on the specimens for 8 h, after which they were immersed in artificial saliva for 16 h, during 14 days. Color assessments were made after 7 and 14 days. The data were analyzed by repeated measures analysis of variance and Tukey's test (5%). Generally, the test groups were unable to increase the bleaching effect (ΔE) significantly compared to the PC group. Only for ΔL, significant higher values compared to the PC group could be seen after 7 days in groups MG (0.02%), and FS (0.002 and 0.003%). The NC group showed significantly lower values than all tested groups. It was concluded that for home bleaching procedures, the addition of chemical activators did not produce a bleaching result significantly higher than the use of 10% carbamide peroxide without activation, and that the concentration of chemical activators used did not significantly influence the effectiveness of treatment. PMID:23390623

  17. Chemical composition, antioxidative and antimicrobial activity of essential oil Ocimum sanctum L.

    Beatović Damir V.; Jelačić Slavica Ć.; Oparnica Čedo D.; Krstić-Milošević Dijana B.; Glamočlija Jasmina M.; Ristić Mihailo S.; Šiljegović Jovana D.

    2013-01-01

    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 o...

  18. Chemical composition, antitumor and antimicrobial activity of Thymus vulgaris and T. algeriensis essential oils

    Nikolic, Milos; Glamočlija, Jasmina; Ćirić, Ana; Ferreira, Isabel C.F.R.; Ricardo C. Calhelha; Perić, Tamara; Marković, Dejan; Giweli, Abdulhamed; Soković, Marina

    2013-01-01

    Plants from genus Thymus are often used in traditional medicine. Some of these species are important medicinal plants that are used in ethnomedicine. In this work, analysis of phytochemicals and bioactivity evaluation of Thymus vulgaris and T. algericnsis essential oils were done. The chemical composition of oils were evaluated using GC/MS; cytotoxic activity was tested against five human tumor cell lines MCF-7 (breast adenocarcinoma), NCI-H460 (non-small cell lung cancer), ...

  19. Chemical Constituents from Andrographis echioides and Their Anti-Inflammatory Activity

    De-Yang Shen; Shin-Hun Juang; Ping-Chung Kuo; Guan-Jhong Huang; Yu-Yi Chan; Damu, Amooru G.; Tian-Shung Wu

    2012-01-01

    Phytochemical investigation of the whole plants of Andrographis echioides afforded two new 2'-oxygenated flavonoids (1) and (2), two new phenyl glycosides (3) and (4), along with 37 known structures. The structures of new compounds were elucidated by spectral analysis and chemical transformation studies. Among the isolated compounds, (1–2) and (6–19) were subjected into the examination for their iNOS inhibitory bioactivity. The structure-activity relationships of the ...

  20. Chemical composition and antiprotozoal activities of Colombian Lippia spp essential oils and their major components

    Patricia Escobar; Sandra Milena Leal; Laura Viviana Herrera; Jairo Rene Martinez; Elena Stashenko

    2010-01-01

    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 com...

  1. CHEMICAL ANALYSIS AND ANTIOXIDANT ACTIVITY OF âNERIUM OLEANDERâ LEAVES

    Lakhmili Siham; Obraim Saida; Taourirte Moha; Seddiqi Nadia; Amraoui Hakima

    2014-01-01

    The phenolic products of medicinal plants have a great pharmacological interest. This product gives the powers of medicinal plants. They are the source of several active principles widely used in modern medicine. The use of Nerium oleander in Moroccan traditional medicine is very common. Few studies have focused on the chemical analysis and phenolic compounds of this plant. For this, we investigated the mineral composition and phenolic combination of the leaves oleander and the study of the a...

  2. Chemical Composition and Antibacterial Activity of Essential Oil of Cosmos bipinnatus Cav. Leaves from South Africa

    Olajuyigbe, Olufunmiso; Ashafa, Anofi

    2014-01-01

    The chemical composition of essential oils isolated from the leaves of Cosmos bipinnatus and its antibacterial activity were analyzed by GC-MS and microbroth dilution assay respectively. The essential oil extracted from this plant was predominantly composed of monoterpenes (69.62%) and sesquiterpenes (22.73%). The antibacterial assay showed that the oil had significant inhibitory effects against both Gram-negative and Gram-positive bacteria isolates. The MIC of Gram-positive strains ranged be...

  3. Chemical composition analysis, antioxidant and antibacterial activity evaluation of essential oil of Atalantia monophylla Correa

    Ramaraj Thirugnanasampandan; Ramya Gunasekar; Madhusudhanan Gogulramnath

    2015-01-01

    Background: Atalantia monophylla Correa. a small tree belongs to the family Rutaceae. It is distributed throughout India and in Tamil Nadu the species is commonly seen in foothills of dry vegetation. Objective: The aim was to hydrodistillate and analyze the chemical composition of essential oil from the fresh leaves of A. monophylla Correa. collected in two different seasons (December, 2013 and May, 2014) and to evaluate antioxidant and antibacterial activities of isolated essential oil. Mate...

  4. Chemical composition and antimicrobial activity of peppermint (Mentha piperita L.) Essential oil

    Mohaddese Mahboubi; Nastaran Kazempour

    2014-01-01

    Peppermint with antiseptic and known healing properties is a plant from the Labiatae family. In this study, we analyzed the chemical composition of essential oil from the flowering aerial part of peppermint by GC and GC/MS. Its antimicrobial activity was evaluated against bacteria, fungi and yeast by micro broth dilution assay. The fractional inhibitory concentration (FIC) and FIC Index (FICI) and related isobologram curve were determined by check board micro titer assay. The results...

  5. Chemical Constituents and Antibacterial and Antifungal Activities of Two Aglaia Species

    WANG,Bin-Gui; LI,Xiao-Ming; PROKSCH,Peter

    2004-01-01

    @@ In the course of searching bioactive natural products from the plant genus Aglaia, we selected two species, A. cordata and A. testicularis, for further chemical study. Totally twenty natural compounds were obtained and structurally elucidated with which eleven of them were discovered for the first time. Among these compounds, lignans, rocaglamides,aglains and bisamides were the main constituents of the two plant species. The results from a bioactive screening indicated that some of the lignans possess potent antibacterial and antifungal activity.

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

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

    2015-01-01

    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.

  7. Comparison of different methods for extraction from Tetraclinis articulata: Yield, chemical composition and antioxidant activity

    Herzi, Nejia; Bouajila, Jalloul; Camy, Séverine; Romdhane, Mehrez; Condoret, Jean-Stéphane

    2013-01-01

    International audience 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 activit...

  8. SEM characterization of carbon nanotubes based active layers of chemical sensors

    Knápek, Alexandr; Mika, Filip; Prášek, J.; Majzlíková, P.

    Piscataway : IEEE, 2014, s. 361-364. ISBN 978-1-4799-4455-2. [International Spring Seminar on Electronics Technology /37./. Dresden (DE), 07.05.2014-11.05.2014] R&D Projects: GA MŠk(CZ) LO1212; GA MŠk EE.2.3.20.0103 Institutional support: RVO:68081731 Keywords : SEM * carbon nanotubes * active layers of chemical sensor s Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  9. Chemical Composition and Antifungal Activity of Ocimum basilicum L. Essential Oil

    Neveen Helmy Abou El-Soud; Mohamed Deabes; Lamia Abou El-Kassem; Mona Khalil

    2015-01-01

    BACKGROUND: The leaves of Ocimum basilicum L. (basil) are used in traditional cuisine as spices; its essential oil has found a wide application in perfumery, dental products as well as antifungal agents. AIM: To assess the chemical composition as well as the in vitro antifungal activity of O. basilicum L. essential oil against Aspergillus flavus fungal growth and aflatoxin B1 production. MATERIAL AND METHODS: The essential oil of O. basilicum was obtained by hydrodistillation and anal...

  10. CHEMICAL, PHYSICAL AND SENSORY ANALYSIS OF ACTIVITY DIFFERENT YEAST SPECIES ON IDENTICAL SUBSTRATE IN WINE PRODUCTION

    Vladimír Vietoris; Hana Balková,Tatiana Bojňanská; Ľubomír Bennár; Peter Czako

    2013-01-01

    Rizling vlašský is the second most important variety in Slovakia. The science of wine production includes a summary of knowledge and experience in the field of grape growing and wine making, or the production of different types of wines using specific methods of production. Wine quality is the result of the interaction between yeast, bacteria and microscopic funguses. In this research, we studied the effects of active dry wine yeasts on chemical, physical and sensory parameters in wine produc...

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

    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

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

    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 ZnCl2 using resorcinol-formaldehyde (RF) resins spheres as precursor. The activation of RF resins spheres by ZnCl2 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 –SO3H groups by a followed sulfonation treating with sulphuric acid and organic sulfonic acid. The results of N2 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 –SO3H groups after sulfonation. The acidities of catalysts were estimated by an indirect titration method and the modified amount of –SO3H groups were examined by energy dispersive spectra. The results suggested sulfonated porous carbon nanospheres catalysts possessed high acidities and –SO3H 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 high acidity and high –SO3H density. • It

  13. Tracking SERS-active nanoprobe intracellular uptake for chemical and biological sensing

    Gregas, Molly K.; Yan, Fei; Scaffidi, Jonathan; Wang, Hsin-Neng; Khoury, Christopher; Zhang, Yan; Vo-Dinh, Tuan

    2007-09-01

    A critical aspect of the use of nanoprobes for intracellular studies in chemical and biological sensing involves a fundamental understanding of their uptake and trajectory in cells. In this study, we describe experiments using surface-enhanced Raman scattering (SERS) spectroscopy and mapping to track cellular uptake of plasmonics-active labeled nanoparticles. Three different Raman-active labels with positive, negative, and neutral charges were conjugated to silver colloidal nanoparticles with the aim of spatially and temporally profiling intracellular delivery and tracking of nanoprobes during uptake in single mammalian cells. 1-D Raman spectra and 2-D Raman mapping are used to identify and locate the probes via their SERS signal intensities. Because Raman spectroscopy is very specific for identification of chemical and molecular signatures, the development of functionalized plasmonics-active nanoprobes capable of exploring intracellular spaces and processes has the ability to provide specific information on the effects of biological and chemical pollutants in the intracellular environment. The results indicate that this technique will allow study of when, where, and how these substances affect cells and living organisms.

  14. Chemical composition, antimicrobial activity and antiviral activity of essential oil of Carum copticum from Iran

    Reza Kazemi Oskuee

    2011-09-01

    Conclusion: The essential oil showed an antiviral activity against phage when phage was pre-incubated with the essential oil prior to its exposure to B. cereus and without any pre-incubation with the phage, suggesting that the oil directly inactivated virus particles.

  15. Chemical and biochemical activities of sonochemically synthesized poly(N-isopropyl acrylamide)/silica nanocomposite

    Chowdhury, Pranesh; Saha, Swadhin Kr; Guha, Arun; Saha, Samar Kr

    2012-11-01

    Poly(N-isopropyl acrylamide) (PNIPA) grafted mesoporous silica nanoparticles (MPSNP) leading to novel inorganic/organic core-shell nanocomposite has been synthesized sonochemically in an aqueous medium without additives like cross-linker, hydrophobic agent, organic solvent. The colloidal stability of MPSNP is enhanced significantly due to encapsulation of the polymer. The composites are characterized by TEM, FTIR and TGA. The chemical and biochemical activities of the sonochemically synthesized materials have been studied in the light of reaction with acid-base, protein adsorption, antimicrobial activity, biocompatibility and nonthrombogenic property. Advantages of sonochemical synthesis compared to other techniques have been evaluated.

  16. CHEMICAL COMPOSITION AND ANTIOXIDANT ACTIVITY OF ESSENTIAL OIL FROM CURCUMA AMADA ROXB.

    Vishnupriya M; Nishaa.S; Sasikumar.J.M; Teepica Priya Darsini.D; Hephzibah Christabel P; Gopalakrishnan V.K

    2012-01-01

    This study was designed to examine the chemical composition and in vitro antioxidant activity of essential oil of Curcuma amada Roxb. The GC- MS analysis of the oil resulted in the identification of 12 compounds. β-myrcene (63.85%) and α-asarone (30.27%) were the two major components identified. The sample was subjected to screening for their possible antioxidant activity by using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical, ABTS radical, Ferric reducing antioxidant power and β-Carotene ble...

  17. Chemical Composition and Biological Activities of Essential Oil from the Rhizomes of Iris bulleyana

    DENG Guo-bin; ZHANG Han-bo; XUE Hong-fen; CHEN Shan-na; CHEN Xiao-lan

    2009-01-01

    Iris bulleyana has long been used as a remedy for detoxication and detumescence.Hydrodistillation was used to extract the essential oil from its rhizomes,and 0.23% oil yield was obtained.Using gas chromatography-mass spectrometry (GCMS) analysis,31 chemicals including aristolone,euparene,β-gurjunene,δ-amorphene,α-muurolene,α-cadinol,camphor,γ-elemene,and τ-eadinol were identified.The essential oil exhibited antibacterial activity against Acetobacter calcoacetica,Bacillus subtillis,Clostridium sporogenes,Clostridium perfringens,Escherichia coli,Salmonella typhii,Staphylococcus aureus,and Yersinia enterocolitica.Its antifungal and antioxidant activities were also tested.

  18. Omani propolis: chemical profiling, antibacterial activity and new propolis plant sources

    2013-01-01

    Background Propolis (bee glue) is a resinous honeybee product having a long history of application in many countries as a traditional remedy for treating wounds, burns, soar throat, stomach disorders, etc. It has been proved to possess beneficial biological effects, including antimicrobial, antioxidant, anti-inflammatory, cytotoxic, antiulcer, and many others. Bees gather propolis from diverse resinous plant parts and in different phytogeographic regions its chemical composition might vary significantly. In this article we report the results of the first study on the chemical profiles of propolis from Oman, its plant origin and antibacterial activity. Results The chemical profiles of Omani propolis extracts were obtained by GC-MS analysis after silylation. Over 50 individual compounds were identified in the samples, belonging to different compound types: sugars, polyols, hydroxy acids, fatty acids, cardanols and cardols, anacardic acids, flavan derivatives, triterpenes, prenylated flavanones and chalcones. The profiles were dissimilar from other known propolis types. They demonstrate that although Oman is not a large country, the plant sources of propolis vary significantly, even in the same apiary and the same season. Based on chemical profiles, and isolation and identification of major marker compounds (new propolis constituents), new plant sources of propolis were found: Azadiracta indica (neem tree) and Acacia spp. (most probably A. nilotica). The ethanol extracts of the studied propolis samples demonstrated activity against S. aureus (MIC < 100 μg. mL-1) and E. coli (MIC < 380 μg. mL-1). Conclusion Omani propolis is different form the known propolis types and demonstrates significant chemical diversity. Its most important plant source is the resin of Azadirachta indica, and as a result its typical components are С5-prenyl flavanones. Other plant sources have been identified, too, playing some role in resin collection by bees in Oman: Acacia spp

  19. Relationship between redox activity and chemical speciation of size-fractionated particulate matter

    Cho Arthur K

    2007-06-01

    Full Text Available Abstract Background Although the mechanisms of airborne particulate matter (PM related health effects remain incompletely understood, one emerging hypothesis is that these adverse effects derive from oxidative stress, initiated by the formation of reactive oxygen species (ROS within affected cells. Typically, ROS are formed in cells through the reduction of oxygen by biological reducing agents, with the catalytic assistance of electron transfer enzymes and redox active chemical species such as redox active organic chemicals and metals. The purpose of this study was to relate the electron transfer ability, or redox activity, of the PM samples to their content in polycyclic aromatic hydrocarbons and various inorganic species. The redox activity of the samples has been shown to correlate with the induction of the stress protein, hemeoxygenase-1. Results Size-fractionated (i.e. Conclusion The results of this work demonstrate the utility of the dithiothreitol assay for quantitatively assessing the redox potential of airborne particulate matter from a wide range of sources. Studies to characterize the redox activity of PM from various sources throughout the Los Angeles basin are currently underway.

  20. Chemical Composition, Antimicrobial and Antioxidant Activities of the Volatile Oil of Ganoderma pfeifferi Bres

    Mohamed Al-Fatimi

    2016-04-01

    Full Text Available In a first study of the volatile oil of the mushroom basidiomycete Ganoderma pfeifferi Bres., the chemical composition and antimicrobial and antioxidant activities of the oil were investigated. The volatile oil was obtained from the fresh fruiting bodies of Ganoderma pfeifferi Bres. By hydrodistillation extraction and analyzed by GC-MS. The antimicrobial activity of the oil was evaluated against five bacteria strains and two types of fungi strains, using disc diffusion and broth microdilution methods. In addition, the antioxidant activity of the oil was determined using DPPH assay. Four volatile compounds representing 90.5% of the total oil were identified. The majority of the essential oil was dominated by 1-octen-3-ol (amyl vinyl carbinol 1 (73.6% followed by 1-octen-3-ol acetate 2 (12.4%, phenylacetaldehyde 3 (3.0% and 6-camphenol 4 (1.5%. The results showed that the Gram-positive bacteria species are more sensitive to the essential oil than Gram-negative bacteria. The oil showed strong antimicrobial activity against Staphylococcus aureus as well as Candida albicans. Moreover, the oil exhibited strong radical scavenging activity in the DPPH assay. This first report on the chemical composition and biological properties of G. pfeifferi volatile oil makes its pharmaceutical uses rational and provides a basis in the biological and phytochemical investigations of the volatile oils of Ganodermataceae species.

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

    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

  2. CHEMICAL COMPOSITION AND ANTIOXIDANT ACTIVITY OF ESSENTIAL OIL FROM CURCUMA AMADA ROXB.

    Vishnupriya.M

    2012-06-01

    Full Text Available This study was designed to examine the chemical composition and in vitro antioxidant activity of essential oil of Curcuma amada Roxb. The GC- MS analysis of the oil resulted in the identification of 12 compounds. β-myrcene (63.85% and α-asarone (30.27% were the two major components identified. The sample was subjected to screening for their possible antioxidant activity by using 2, 2-diphenyl-1-picrylhydrazyl (DPPH radical, ABTS radical, Ferric reducing antioxidant power and β-Carotene bleaching assay. Results showed that the essential oil possessed a strong degree of antioxidant activity in terms of β-Carotene bleaching capacity followed by ABTS radical, ferric reducing power and a moderate DPPH radical scavenging activity. This study concludes that the essential oil from Curcuma amada Roxb could serve as an important bioresource of antioxidants for using in food and pharmaceutical industry.

  3. Chemical Signals of Synthetic Disaccharide Derivatives Dominate Rhamnolipids at Controlling Multiple Bacterial Activities.

    Singh, Nischal; Shetye, Gauri S; Zheng, Hewen; Sun, Jiayue; Luk, Yan-Yeung

    2016-01-01

    Microbes secrete molecules that modify their environment. Here, we demonstrate a class of synthetic disaccharide derivatives (DSDs) that mimics and dominates the activity of naturally secreted rhamnolipids by Pseudomonas aeruginosa. The DSDs exhibit the dual function of activating and inhibiting the swarming motility through a concentration-dependent activity reversal that is characteristic of signaling molecules. Whereas DSDs tethered with a saturated farnesyl group exhibit inhibition of both biofilm formation and swarming motility, with higher activities than rhamnolipids, a saturated farnesyl tethered with a sulfonate group only inhibits swarming motility but promote biofilm formation. These results identified important structural elements for controlling swarming motility, biofilm formation, and bacterial adhesion and suggest an effective chemical approach to control intertwined signaling processes that are important for biofilm formation and motilities. PMID:26511780

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

    Kovtun, Maxim, E-mail: max.kovtun@up.ac.za; Kearsley, Elsabe P., E-mail: elsabe.kearsley@up.ac.za; Shekhovtsova, Julia, E-mail: j.shekhovtsova@gmail.com

    2015-06-15

    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.

  5. Chemical composition, nutritional value, and antioxidant activities of eight mulberry cultivars from China

    Linghong Liang

    2012-01-01

    Full Text Available Background: Mulberry (Morus, Moraceae is widely distributed in the temperate, subtropical, or tropical regions of the world, while there are no conclusive reports on the chemical composition, nutritional value, and antioxidant properties of mulberry cultivars from China. Objective: To investigate chemical properties and to determine proximate nutritive compounds of the eight mulberry cultivars. Materials and Methods: Chemical properties (including moisture, ash, total dry matter, total soluble solids, pH, and total titratable acidity of the eight mulberry cultivars were investigated. Proximate nutritive compounds (including crude protein, crude fat, mineral elements, total anthocyanins, total polyphenols, total flavonoids, and total sugars were also determined. Results: The results indicated that the moisture contents were 70.0-87.4%, the crude protein contents 1.62-5.54%, and the crude fat contents from 1.23-2.23%. The major fatty acids in mulberry fruits were linoleic acid (C 18:2 and palmitic acid (C 16:0 , 26.40-74.77% and 9.29-22.26%, respectively. Mulberry fruit is also a good source of minerals and the potassium content (521.37-1718.60 mg/100g DW is especially higher than that of other elements. Compared with other species, the Morus atropurpurea Roxb. had relatively high total polyphenols content (189.67-246.00 mg GAE/100mg and anthocyanins content (114.67-193.00 mg/100mg. There was a good linear correlation between antioxidant activity and total polyphenols content. Conclusion: Significant differences of the chemical composition, nutritional value, and antioxidant activities among the mulberry cultivars were observed, the Morus atropurpurea Roxb. showed considerable high nutritional value and antioxidant activity which could be developed for functional food that benefits human health.

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

    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.

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

    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.

  8. Effects of chemical activation and season on birth efficiency of cloned pigs

    2009-01-01

    The effects of chemical activation on birth efficiency of cloned pigs were studied by investigating the developmental process from porcine oocyte activation to birth of cloned pigs.Three different activation methods were used:(i) Electroporation(Ele);(ii) Ele followed by incubation with 6-dimethylaminopurine(6-DMAP);and(iii) Ele followed by a treatment with cycloheximide(CHX).In experiment 1,the rates of cleavage,developmental rates and cell number of porcine parthenogenetic(PA) embryos were investigated in the three treatment groups.In experiment 2,NT embryos produced by the three different activation treatments were compared for the rates of cleavage,development and cell number.Finally,the effects of Ele and Ele+CHX activation methods on birth efficiency of cloned pigs were compared.The activated oocytes treated by combination activation generally showed a higher(P<0.05) blastocyst rate and produced more expanded blastocysts than oocytes activated with Ele.The rates of cleavage and total cell number of parthenotes were not significantly different.Parthenogenetic embryos activated with 6-DMAP developed into blastocyst and expanded blastocyst stages at a significantly(P<0.05) higher rate than those treated with Ele,but the developmental capability was dramatically decreased in NT embryos.With the CHX activation method,the NT embryo blastocyst rate was substantially(P<0.05) increased although the production of expanded blastocysts was not significantly different from that by the other two methods.The birth rate of cloned pigs increased in the CHX group,though the rate was not significantly different from Ele.The effects of season on developmental rate of the porcine PA embryos and birth rate of cloned pigs were also examined in our study.Porcine oocytes collected in the spring had higher developmental capabilities than those collected in the winter.However,no difference in birth rate of the cloned pigs was found between the oocytes collected in the two seasons

  9. Effects of chemical activation and season on birth efficiency of cloned pigs

    MA YuFang; LI Yan; WEI HengXi; LI QiuYan; FANG Rui; ZHAO Rui; ZHANG Kun; XUE Kai; LOU YanKun; DAI YunPing; LIAN LinSheng; LI Ning

    2009-01-01

    The effects of chemical activation on birth efficiency of cloned pigs were studied by investigating the developmental process from porcine oocyte activation to birth of cloned pigs. Three different activation methods were used: (i) Electroporation (Ele); (ii) Ele followed by incubation with 6-dimethylaminopurine (6-DMAP); and (iii) Ele followed by a treatment with cycloheximide (CHX). In experiment 1, the rates of cleavage, developmental rates and cell number of porcine parthenogenetic (PA) embryos were investigated in the three treatment groups. In experiment 2, NT embryos produced by the three different activation treatments were compared for the rates of cleavage, development and cell number. Finally, the effects of Eie and Ele+CHX activation methods on birth efficiency of cloned pigs were compared. The activated oocytes treated by combination activation generally showed a higher (P<0.05) blastocyst rate and produced more expanded blastocysts than oocytes activated with Ele. The rates of cleavage and total cell number of parthenotes were not significantly different. Parthenogenetic embryos activated with 6-DMAP developed into blastocyst and expanded blsstocyst stages at a significantly (P<0.05) higher rate than those treated with Ele, but the developmental capability was dramatically decreased In NT embryos. With the CHX activation method, the NT embryo blastocyst rate was substantially (P<0.05) increased although the production of expanded blastocysts was not significantly different from that by the other two methods. The birth rate of cloned pigs increased in the CHX group, though the rate was not significantly different from Ele. The effects of season on developmental rate of the porcine PA embryos and birth rate of cloned pigs were also examined in our study. Porcine oocytes collected in the spring had higher developmental capabilities than those collected in the winter. However, no difference in birth rate of the cloned pigs was found between the oocytes

  10. 76 FR 76935 - Impact of Implementing the Chemical Weapons Convention (CWC) on Commercial Activities Involving...

    2011-12-09

    ... Bureau of Industry and Security Impact of Implementing the Chemical Weapons Convention (CWC) on... implementation of the Chemical Weapons Convention (CWC), through the Chemical Weapons Convention Implementation Act (CWCIA), and the Chemical Weapons Convention Regulations (CWCR), has had on commercial...

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

    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

  12. Changes in soil chemical characters and enzyme activities during continuous monocropping of cucumber (cucumis sativus)

    Soil sickness, a phenomenon of negative plant-soil feedback in continuous monocropping systems, can cause severe yield penalty in agricultural production. Changes in soil chemical and biological characters are thought to account for soil sickness. However, changes in soil properties in continuous monocropping systems and links between these changes and plant growth performance are still not clear. In this study, dynamics of soil chemical characters and enzyme activities were monitored in a continuously monocropped cucumber system, in which cucumber was successively monocropped in pots for nine croppings under greenhouse conditions from 2005 to 2009 in the experimental station of Northeast Agricultural University, Harbin, China. Cucumber showed an obvious stunted growth behavior in the seventh cropping and turned better in the ninth cropping. Soil pH decreased from the first cropping to the seventh cropping and increased in the ninth cropping. Contents of soil available nitrogen, phosphorous and potassium were the highest while activities of soil urease, neutral phosphatase and catalase were the lowest in the seventh cropping. Our results suggested that cucumber in the seventh cropping did not absorb enough soil nutrients, which may lead to the decrease in soil pH and changed soil biological properties. Changes in soil chemical and biological characters may be linked to the soil sickness of cucumber. (author)

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

    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. Chemical composition analysis, antioxidant and antibacterial activity evaluation of essential oil of Atalantia monophylla Correa

    Ramaraj Thirugnanasampandan

    2015-01-01

    Full Text Available Background: Atalantia monophylla Correa. a small tree belongs to the family Rutaceae. It is distributed throughout India and in Tamil Nadu the species is commonly seen in foothills of dry vegetation. Objective: The aim was to hydrodistillate and analyze the chemical composition of essential oil from the fresh leaves of A. monophylla Correa. collected in two different seasons (December, 2013 and May, 2014 and to evaluate antioxidant and antibacterial activities of isolated essential oil. Materials and Methods: Chemical composition of isolated essential oil was analyzed by gas chromatography, gas chromatography coupled with mass spectrometry. Antioxidant activity of oil was assessed using five different antioxidant test systems. Antibacterial activity of oil was tested against six pathogenic bacteria by broth dilution method. Results: Essential oil obtained from the leaves collected during May, 2014 had shown more compounds. Antioxidant activity of oil was moderate when compared with positive control. Minimum inhibitory concentration value of oil was ranges between 139.32 ± 0.001 and 541.11 ± 0.003 µg/mL against all the tested bacteria. Conclusion: Result clearly indicates essential oil collected during May, 2014 showed more bioactive compounds.

  15. The chemical origin and catalytic activity of coinage metals: from oxidation to dehydrogenation.

    Syu, Cih-Ying; Yang, Hao-Wen; Hsu, Fu-Hsing; Wang, Jeng-Han

    2014-04-28

    The high oxidation activity of coinage metals (Cu, Ag and Au) has been widely applied in various important reactions, such as oxidation of carbon monoxide, alkenes or alcohols. The catalytic behavior of those inert metals has mostly been attributable to their size effect, the physical effect. In the present study, the chemical effects on their high oxidation activity have been investigated. We mechanistically examine the direct and oxidative dehydrogenation (partial oxidation) reactions of ethanol to acetaldehyde on a series of transition metals (groups 9, 10 and 11) with identical physical characteristics and varied chemical origins using density functional theory (DFT) calculations and electronic structure analyses at the GGA-PW91 level. The energetic results show that coinage metals have much lower activation energies and higher exothermicities for the oxidative dehydrogenation steps although they have higher energy for the direct dehydrogenation reaction. In the electronic structure analyses, coinage metals with saturated d bands can efficiently donate electrons to O* and OH*, or other electronegative adspecies, and better promote their p bands to higher energy levels. The negatively charged O* and OH* with high-lying p bands are responsible for lowering the energies in oxidative steps. The mechanistic understanding well explains the better oxidation activity of coinage metals and provides valuable information on their utilization in other useful applications, for example, the dehydrogenation process. PMID:24626959

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

    Machado, Christiane Schineider; Mokochinski, João Benhur; de Lira, Tatiana Onofre; de Oliveira, Fátima de Cassia Evangelista; Cardoso, Magda Vieira; Ferreira, Roseane Guimarães; Sawaya, Alexandra Christine Helena Frankland; Ferreira, Antonio Gilberto; Pessoa, Cláudia; Cuesta-Rubio, Osmany; Monteiro, Marta Chagas; de Campos, Mônica Soares

    2016-01-01

    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. PMID:27525023

  17. Chemical Diversity and Antimicrobial Activity of Salvia multicaulis Vahl Essential Oils.

    Fahed, Layal; Stien, Didier; Ouaini, Naïm; Eparvier, Véronique; El Beyrouthy, Marc

    2016-05-01

    The chemical compositions and antimicrobial activities of the essential oils (EOs) of aerial parts of Salvia multicaulis Vahl, collected during the same week from two different Lebanese regions, were investigated. The EOs were obtained by hydrodistillation using a Clevenger-type apparatus and characterized by GC and GC/MS analyses. The minimum inhibitory concentrations of these EOs were determined against one Gram-negative and two Gram-positive bacteria, one yeast, and five dermatophytes using the broth microdilution technique. One EO was notably active against Staphylococcus aureus, methicillin-resistant S. aureus, and all of the Trichophyton species tested. Nerolidol was found to be the major compound in the active oil; nerolidol was also absent from the inactive oil. This study demonstrated that nerolidol shows antimicrobial activity and therefore significantly contributes to the antimicrobial potential of the oil. The chemical diversity of worldwide S. multicaulis EOs was analyzed, revealing that the EOs of this study belong to two different chemotypes found in the literature. The nerolidol chemotype appears to be restricted to Lebanon, and it can be used as antimicrobial agent against external bacterial and fungal infections. PMID:27038067

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

    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.

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

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

    2011-01-01

    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. PMID:21959299

  20. Effects of coal rank on the chemical composition and toxicological activity of coal liquefaction materials

    Wright, C.W.; Dauble, D.D.

    1986-05-01

    This report presents data from the chemical analysis and toxicological testing of coal liquefaction materials from the EDS and H-Coal processes operated using different ranks of coal. Samples of recycle solvent from the bottoms recycle mode of the EDS direct coal liquefaction process derived from bituminous, sub-bituminous, and lignite coals were analyzed. In addition, the H-Coal heavy fuel oils derived from bituminous and sub-bituminous coals were analyzed. Chemical methods of analysis included adsoprtion column chromatography, high-resolution gas chromatography, gas chromatography/mass spectrometry, and low-voltage probe-inlet mass spectrometry. The toxicological activity of selected samples was evaluated using the standard microbial mutagenicity assay, an initiation/promotion assay for mouse-skin tumorigenicity, and a static bioassy with Daphnia magna for aquatic toxicity of the water-soluble fractions. 22 refs., 16 figs., 14 tabs.

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

    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. PMID:23390579

  2. Instrumental neutron activation analysis applied to the chemical composition of steel

    In the technological application of steel, the knowledge of its chemical composition is of fundamental importance as it is directly related to various properties, such as, mechanical properties, corrosion resistance, temperability and others. Instrumental Neutron Activation Analysis, INAA, is an appropriate technique in the evaluation of the chemical composition of steel and other metallurgical materials due to the possibility of simultaneous determination of a great number of elements without the inconvenience of sample dissolution. Element determination is achieved with good accuracy and precision for major and minor constituents as well as for trace elements. In this paper, INAA was used in the determination of As, Co, Cu, Mn, Mo, V and W in steel and iron samples and in certified reference materials. The obtained accuracy and precision were less than 10% for most of the elements confirming the possibility of its use in the study of metallic samples and in the certification of new reference materials. (author)

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

    Nedjimi, Bouzid [Djelfa Univ. (Algeria). Lab. of Exploration and Valorization of Steppe Ecosystem; Beladel, Brahim [Djelfa Univ. (Algeria)

    2015-09-01

    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.

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

    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.

  5. Chemical Compositions, Antioxidant and Antimicrobial Activities of Essential Oils of Piper caninum Blume

    Hasnah Mohd Sirat

    2011-11-01

    Full Text Available Chemical composition, antioxidant and antimicrobial activities of the fresh leaves and stems oils of Piper caninum were investigated. A total of forty eight constituents were identified in the leaves (77.9% and stems (87.0% oil which were characterized by high proportions of phenylpropanoid, safrole with 17.1% for leaves and 25.5% for stems oil. Antioxidant activities were evaluated by using β-carotene/linoleic acid bleaching, DPPH radical scavenging and total phenolic content. Stems oil showed the highest inhibitory activity towards lipid peroxidation (114.9 ± 0.9%, compared to BHT (95.5 ± 0.5%, while leaves oil showed significant total phenolic content (27.4 ± 0.5 mg GA/g equivalent to gallic acid. However, the essential oils showed weak activity towards DPPH free-radical scavenging. Evaluation of antimicrobial activity revealed that both oils exhibited strong activity against all bacteria strains with MIC values in the range 62.5 to 250 µg/mL, but weak activity against fungal strains. These findings suggest that the essential oils can be used as antioxidant and antimicrobial agents for therapeutic, nutraceutical industries and food manufactures.

  6. Neem cake: chemical composition and larvicidal activity on Asian tiger mosquito.

    Nicoletti, Marcello; Mariani, Susanna; Maccioni, Oliviero; Coccioletti, Tiziana; Murugan, Kardaray

    2012-07-01

    New pesticides based on natural products are urgently needed, in consideration of their environmental care and lower collateral effects. Neem oil, the main product obtained from Azadiractha indica A. Juss, commonly known as neem tree, is mainly used in medical devices, cosmetics and soaps, as well as important insecticide. Manufacturing of neem oil first includes the collection of the neem seeds as raw material used for the extraction. Neem cake is the waste by-product remaining after extraction processes. The quality of the oil, as that of the cake, strictly depends from the quality of seeds as well as from the type of extraction processes used, which strongly influences the chemical composition of the product. Currently, the different types of commercial neem cake on the market are roughly identified as oiled and deoiled cake, but several other differences can be detected. The differences are relevant and must be determined, to obtain the necessary correlation between chemical constitution and larvicidal activities. Six different batches of neem cake, marketed by several Indian and European companies, were analyzed by HPLC and HPTLC, and their fingerprints compared, obtaining information about the different compositions, focusing in particular on nortriterpenes, considered as the main active components of neem oil. Therefore, the chemical composition of each cake was connected with the biological activitiy, i.e., the effects of the extracts of the six neem cakes were tested on eggs and larvae of Aedes albopictus (Stegomyia albopicta) (Diptera: Culicidae), commonly known as Asian tiger mosquito. The results confirmed the previously reported larvicide effects of neem cake that, however, can now be related to the chemical composition, in particular with nortriterpenes, allowing in that way to discriminate between the quality of the various marketed products, as potential domestic insecticides. PMID:22422292

  7. Chemical composition and antioxidant activities of the essential oil from Nandina domestica fruits.

    Bi, Shu-Feng; Zhu, Guang-Qi; Wu, Jie; Li, Zhong-Kang; Lv, Yong-Zhan; Fang, Ling

    2016-01-01

    The chemical composition and antioxidant activities of the essential oil from Nandina domestica fruits were studied for the first time. Twenty-two compounds, representing 82.79% of the oil, were identified from the oil. The major compounds were 3-hexen-1-ol (12.9%), linalool (12.3%), 2-methoxy-4-vinylphenol (9.9%), oleic acid (8.0%), furfural (5.8%) and 2,6-di-tert-butyl-4-methylphenol (5.7%). The antioxidant activities of the oil were evaluated using reducing power, metal chelating ability and scavenging capacity against 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azinobis-3-ethylbenzthiazoline-6-sulfonate (ABTS) and superoxide anion free radical. The oil exhibited significant antioxidant activities. PMID:26199150

  8. Chemical composition and antimicrobial activity of essential oil isolated from the cultured mycelia of Ganoderma japonicum

    Dandan Liu; Zheng Hu; Zhigang Liu; Bo Yang; Wenjuan Tu; Liang Li

    2009-01-01

    Objective:To explore a new natural antibiotic. Methods:The chemical composition of the essential oil from Ganoderma japonicum (G. japonicum) mycelia was analyzed by gas chromatography-mass spectrometry(GC-MS). The antimicrobial activity of the oil was evaluated against eighteen microorganisms, including bacteria, mildew and yeast by using a disc diffusion method. Furthermore, the minimum inhibitory concentrations(MIC) and the minimum bactericidal concentrations(MBC) of the essential oil against twelve clinical pathogens were determined. Results:The main components of the oil were nerolidol, decadienal, linaiool and benzyl alcohol. The antimicrobial results indicated that the oil inhibited all the tested bacterium, especially Methicillin-resistant Staphylococcus aureus (MRSA) in which the antibacterial activity exhibited a MBC of 1.03 mg/ml. Conclusion: The essential oil of G.japonicum mycelium has significant inhibitory activity. It is a potential medicinal resource that can be used as a natural antibiotic.

  9. The essential oil of Populus balsamifera buds: its chemical composition and cytotoxic activity.

    Piochon-Gauthier, Marianne; Legault, Jean; Sylvestre, Muriel; Pichette, André

    2014-02-01

    The chemical composition of Populus balsamifera essential oils obtained from spring buds, fall buds, and young leaves were determined by GC and GC-MS analyses. The major constituent, (+)-alpha-bisabolol, a rare sesquiterpene, was isolated from spring oil using reverse-phase preparative HPLC. The cytotoxic activity of balsam poplar oils and isolated (+)-alpha-bisabolol was assessed in vitro against human lung carcinoma (A549) and colorectal adenocarcinoma (DLD-1) cell lines. Essential oils were cytotoxic with IC50 ranging from 35 to 50 microg/mL. (+)-alpha-Bisabolol exhibited pronounced activity (IC50 14 microg/mL) against both cancer cell lines. It also exhibited interesting cytotoxic activity (IC50 23 microg/mL) against human glioma (U251), higher than the one observed for (-)-alpha-bisabolol (IC50 34 microg/mL), which is known for its apoptosis-inducing effect against glioma cells. PMID:24689304

  10. Chemical Composition and Antimicrobial Activity of Thymus praecox Opiz ssp. polytrichus Essential Oil from Serbia

    Nada V. Petrović

    2016-03-01

    Full Text Available Chemical composition and antimicrobial activity of the essential oil of wild growing Thymus praecox Opiz ssp. polytrichus were studied. trans-Nerolidol (19.79%, germacrene D (18.48% and thymol (9.62% were the main components in essential oil. This study is the first report of the antimicrobial activity of essential oil obtained from the T. praecox Opiz ssp. polytrichus. Antimicrobial activity of essential oil was investigated on Bacillus cereus, Micrococcus flavus, Staphylococcus aureus, Listeria monocytogenes, Escherichia coli, Pseudomonas aeruginosa, Enterobacter cloacae, Salmonella typhimurium, Aspergillus fumigatus, A. versicolor, A. ochraceus, A. niger, Trichoderma viride, Penicillium funiculosum, P. ochrochloron, and P. verrucosum var. cyclopium strains. In the antimicrobial assays, essential oil showed high antimicrobial potential (MIC 19–150 m g/mL, MBC 39–300 m g/mL for bacteria; and MIC 19.5–39 m g/mL, MFC 39–78 m g/mL for fungi.

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

    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. PMID:25632490

  12. Antimycobacterial activity of chemically defined natural substances from the Caribbean flora in Guadeloupe.

    Rastogi, N; Abaul, J; Goh, K S; Devallois, A; Philogène, E; Bourgeois, P

    1998-04-01

    Eight chemically defined, naturally occurring compounds were extracted from the tropical flora of the Caribbean island of Guadeloupe: pilocarpine, an alkaloid from Pilocarpus racemosus; heraclenol and isomeranzin, coumarins from Triphasia trifolia; lochnerin, an indole alkaloid from Rauwolfia biauriculata; ibogaine and voacangine, indole alkaloids from Tabernaemontana citrifolia; texalin, an oxazole from Amyris elemifera; and canellal, a sesquiterpene dialdehyde from Canella winterana. An essential oil fraction from Canella winterana was also tested. The antimycobacterial activity of these substances was tested against Mycobacterium tuberculosis, M. avium and M. kansasii using the Middlebrook 7H11 agar medium, the Bactec 460-TB radiometric methodology, and determination of bacterial viable counts. Three compounds, namely ibogaine, voacangine and texalin, showed antimycobacterial activity. Investigations on the structure-modification and structure-activity relationships of these compounds may help determine new targets for future drug development. PMID:9626931

  13. Relating particle hygroscopicity and CCN activity to chemical composition during the HCCT-2010 field campaign

    Z. J. Wu

    2013-03-01

    Full Text Available Particle hygroscopic growth at RH =90%, cloud condensation nuclei (CCN activity, and size-resolved chemical composition were concurrently measured in the Thüringer Wald mid-level mountain range in central Germany in fall season of 2010. The median hygroscopicity parameter values, κ, of 50, 75, 100, 150, 200, and 250 nm particles derived from hygroscopicity measurements are respectively 0.14, 0.14, 0.17, 0.21, 0.24, and 0.28 during the sampling period. The closure between HTDMA-measured (κHTDMA and chemical composition-derived (κchem hygroscopicity parameters was performed based on the Zdanovskii–Stokes–Robinson (ZSR mixing rule. Using size-averaged chemical composition, the κ values are substantially overpredicted (30% and 40% for 150 and 100 nm particles. Introducing size-resolved chemical composition substantially improved closure, and the differences between κHTDMA and κchem are within 10%. We found that the evaporation of NH4NO3, which may happen in H-TDMA system, could lead to a discrepancy in predicted and measured particle hygroscopic growth. The hygroscopic parameter of the organic fraction, κorg is positively correlated with the O : C ratio (κorg =0.19 · (O : C−0.03. Such correlation is helpful to define the κorg value in the closure study. κ derived from CCN measurement was around 30% (varied with particle diameters higher than that determined from particle hygroscopic growth measurements (here, hydrophilic mode is considered only. This difference might be explained by the surface tension effects, solution non-ideality, and the partial solubility of constituents or non-dissolved particle matter. However, due to these effects being included in HTDMA-derived κ calculations, we could not distinguish the specific roles of these effects in creating this gap. Therefore, extrapolating from HTDMA data to properties at the point of activation should be done with great care. Finally, closure study between CCNc-measured (κ

  14. Screening of 397 chemicals and development of a quantitative structure-activity relationship model for androgen receptor antagonism

    Vinggaard, Annemarie; Niemelä, Jay Russell; Wedebye, Eva Bay; Jensen, Gunde Egeskov

    2008-01-01

    We have screened 397 chemicals for human androgen receptor (AR) antagonism by a sensitive reporter gene assay to generate data for the development of a quantitative structure-activity relationship (QSAR) model. A total of 523 chemicals comprising data on 292 chemicals from our laboratory and data...... synthetic androgen R1881. The MultiCASE expert system was used to construct a QSAR model for AR antagonizing potential. A "5 Times, 2-Fold 50% Cross Validation" of the model showed a sensitivity of 64%, a specificity of 84%, and a concordance of 76%. Data for 102 chemicals were generated for an external...... validation of the model resulting in a sensitivity of 57%, a specificity of 98%, and a concordance of 92% of the model. The model was run on a set of 176103 chemicals, and 47% were within the domain of the model. Approximately 8% of chemicals was predicted active for AR antagonism. We conclude that the...

  15. Chemical composition and mosquito repellent activity of the essential oil of Plectranthus incanus link

    Pal Mahesh

    2011-01-01

    Full Text Available The chemical composition of the essential oil obtained from the leaves of Plectranthus incanus Link, with the yield of 0.6% (w/v, was analyzed by GC and GC/MS. A total of 16 constituents, representing 95.2% of the oil, were identified. The major components of the oil were fenchone (6.0%, piperitone oxide (32.4%, piperitenone (3.0% and piperitenone oxide (41.5%. The repellent activity of the volatile oil at different concentrations was measured by the protection period against the bites of Anopheles stephensi and Culex fatigans. The tested oil had stronger repellent activity than citronella oil, which was used as a positive control. LC50 (30 min for P. incanus oil against An. stephensi and C. fatigans were 23.8 and 19.6 μl/L air, respectively, whereas LC50 of citronella oil were 31.7 and 31.0 μl/L air. Thus, P. incanus may be regarded as a potential valuable source of chemicals that have strong mosquito repellent activity, and could be used for the preparation of mosquito repellent formulations.

  16. Effects of pore structure on the high-performance capacitive deionization using chemically activated carbon nanofibers.

    Im, Ji Sun; Kim, Jong Gu; Lee, Young-Seak

    2014-03-01

    Capacitive deionization (CDI) electrodes were constructed from activated carbon fibers prepared using electrospinning and chemical activation. The CDI efficiencies of these electrodes were studied as a function of their specific surface areas, pore volumes and pore sizes via salt ion adsorption. The specific surface areas increased approximately 90 fold and the pore volume also increased approximately 26 fold with the use of greater amounts of the chemical activation agent. There was a relative increase in the mesopore fraction with higher porosity. A NaCI solution was passed through a prepared CDI system, and the salt removal efficiency of the CDI system was determined by the separation of the Na+ and Cl- ions toward the anode and cathode. The CDI efficiency increased with greater specific surface areas and pore volumes. In addition, the efficiency per unit pore volume increased with a reduction in the micropore fraction, resulting in the suppressed overlapping effect. In conclusion, the obtained improvements in CDI efficiency were mainly attributed to mesopores, but the micropores also played an important role in the high-performance CDI under conditions of high applied potential and high ion concentrations. PMID:24745222

  17. Chemical composition and antimicrobial activity of the essential oil from leaves of Algerian Melissa officinalis L.

    Abdellatif, Fahima; Boudjella, Hadjira; Zitouni, Abdelghani; Hassani, Aicha

    2014-01-01

    The essential oil obtained from leaves of Melissa officinalis L. (Family of Lamiaceae) growing in Algeria, was investigated for its chemical composition and in vitro antimicrobial activity. The chemical composition was determined by hydrodistillation and analyzed by GC/MS and GC-FID. Sixty-three compounds were identified in the essential oil, representing 94.10 % of the total oil and the yields were 0.34 %. The major component was geranial (44.20 %). Other predominant components were neral (30.20 %) and citronellal (6.30 %). The in vitro antimicrobial activity was determined by paper disk agar diffusion testing and minimum inhibitory concentration (MIC) using 7 bacteria (3 Gram-positive and 4 Gram-negative), 2 yeasts and 3 fungi. The results showed that the essential oil presented high antimicrobial activity against all microorganisms targeted mainly against five human pathogenic bacteria, one yeast Candida albicans and two phytopathogenic fungi tested. The minimum inhibitory concentrations (MIC) ranged from 1.00 to 5.00 µL/mL. PMID:26417300

  18. The physico-chemical properties and biostimulative activities of humic substances regenerated from lignite.

    David, Jan; Smejkalová, Daniela; Hudecová, Sárka; Zmeškal, Oldřich; von Wandruszka, Ray; Gregor, Tomáš; Kučerík, Jiří

    2014-01-01

    The positive effect of humic acids on the growth of plant roots is well known, however, the mechanisms and role of their physical structure in these processes have not been fully explained yet. In this work, South-Moravian lignite was oxidized by means of nitric acid and hydrogen peroxide to produce a set of regenerated humic acids. The elemental composition, solid state stability and solution characteristics were determined and correlated in vitro with their biological activity. A modified hydroponic method was applied to determine the effects of their potassium salts on Zea mays seedlings roots with respect to the plant weight, root length, root division, and starch and protein content. The relations between the determined parameters were evaluated through Principal Component Analysis and Pearson's correlation coefficients. The results indicated that the most important factor determining the biological activity of South-Moravian lignite potassium humates is related to the nature of self-assemblies, while the chemical composition had no direct connection with the root growth of Zea mays seedlings. It was demonstrated a controlled processing that provided humic substances with different chemical and physicochemical properties and variable biological activity. PMID:24790812

  19. Chemical Composition and in Vitro Antifungal Activity Screening of the Allium ursinum L. (Liliaceae

    Radu Vasile Bagiu

    2012-01-01

    Full Text Available The objective of the study was to summarize the methods for isolating and identifying natural sulfur compounds from Allium ursinum (ramson and to discuss the active constituents with regard to antifungal action. Using chromatographic techniques, the active constituents were isolated and subsequently identified. Analyses by high-performance liquid chromatography (HPLC suggested that these compounds were sulfur constituents, with a characteristic absorbance at 250 nm. Gas chromatography-mass spectrometry (GC-MS analyses allowed the chemical structures of the isolated constituents to be postulated. We adopted the same methods to identify the health-giving profiling of ramsons and the effects are thought to be primarily derived from the presence and breakdown of the alk(enylcysteine sulphoxide, alliin and its subsequent breakdown to allicin (sulfur-compounds of ramson in connection with antifungal action. The aim of the study was the characterization of the chemical composition of ramsons and the testing of the action of the in vitro extracts, on different strains of Candida albicans. The main goal was to highlight the most efficient extracts of Allium ursinum that can provide long-term antifungal activity without remissions. The extracts from Allium ursinum plants, inhibited growth of Candida spp. cells at concentrations ranging from 0.5 to 4.0 mg/mL, while that of adherent cells at concentrations ranging from 1.0 to > 4.0 mg/mL, depending on the yeast and plant species.

  20. Chamomile and marigold tea: chemical characterization and evaluation of anticancer activity.

    Matić, Ivana Z; Juranić, Zorica; Savikin, Katarina; Zdunić, Gordana; Nađvinski, Neva; Gođevac, Dejan

    2013-06-01

    With the aim to evaluate the selectivity in the antitumor action, the cytotoxic activity of chamomile and marigold tea was tested against various malignant cell lines and against healthy immunocompetent peripheral blood mononuclear cells (PBMC). Chemical profiles of chamomile and marigold infusions and decoctions were analyzed by liquid chromatography/mass spectrometry; their total phenolic content and radical scavenging activity were determined, too. Results from present research demonstrate that chamomile and marigold tea exert selective dose-dependent cytotoxic action against target cancer cells. It is noteworthy that cytotoxicity of tea prepared from Calendula officinalis is remarkably higher in comparison to that from Matricaria recutita tea. The cytotoxic effect of chamomile tea is very weak to healthy PBMC, while the effect of marigold tea on PBMC is more pronounced. Marigold tea exerts highly selective antitumor effect especially to melanoma Fem-x cells in comparison to the action to normal healthy PBMC. Chemical analyses show that dominant phenolic compounds in examined infusions and decoctions are flavonoid glycosides and hydroxycinnamic acid derivatives. There are no considerable differences in total phenolic content and antioxidant activity between examined infusions. Antitumor potential of chamomile and marigold tea should be further investigated. PMID:22899374

  1. Chemical Composition Analysis, Antimicrobial Activity and Cytotoxicity Screening of Moss Extracts (Moss Phytochemistry

    Laura Klavina

    2015-09-01

    Full Text Available Mosses have been neglected as a study subject for a long time. Recent research shows that mosses contain remarkable and unique substances with high biological activity. The aim of this study, accordingly, was to analyze the composition of mosses and to screen their antimicrobial and anticancer activity. The total concentration of polyphenols and carbohydrates, the amount of dry residue and the radical scavenging activity were determined for a preliminary evaluation of the chemical composition of moss extracts. In order to analyze and identify the substances present in mosses, two types of extrahents (chloroform, ethanol and the GC/MS and LC-TOF-MS methods were used. The antimicrobial activity was tested on four bacteria strains, and the anticancer activity on six cancer cell lines. The obtained results show the presence of a high number of primary (fatty acids and amino acids, but mainly secondary metabolites in moss extracts—including, sterols, terpenoids, polyphenols and others—and a high activity with respect to the studied test organisms.

  2. Chemical composition and antioxidant and antimycobacterial activities of Bromelia balansae (Bromeliaceae).

    Coelho, Roberta Gomes; Honda, Neli Kika; Vieira, Maria do Carmo; Brum, Rosenei Louzada; Pavan, Fernando Rogério; Leite, Clarice Queico Fujimura; Cardoso, Claudia Andréa Lima

    2010-10-01

    Bromelia balansae (Family Bromeliaceae) is a medicinal plant commonly used in the central region of Brazil as a cough syrup and also eaten roasted. The methanolic extract of ripe fruits was analyzed by chromatographic methods and spectrometrically. Four glycoside flavonols were isolated: kaempferol-3-O-α-L-rhamnopyranoside (1), kaempferol-3-O-α-L-rhamnopyranosyl-(1-->6)-ß-D-glucopyranoside (2), quercetin-3-O-α-L-rhamnopyranosyl-(1-->6)-ß-d-glucopyranoside (3), and kaempferol 3,7-di-O-α-L-rhamnopyranoside (4). The resazurin microtiter assay was used to measure the biological activity in vitro against Mycobacterium tuberculosis. The results showed a moderate activity of the methanolic extract with a minimal inhibitory concentration of 128 μg/mL. Antioxidant activity was evaluated as free radical scavenging capacity and inhibition of peroxidation. Free radical scavenging capacity was assessed by measuring the scavenging activity of methanolic extract and methanolic fraction on 2,2-diphenyl-1-picrylhydrazyl radical. The methanolic extract showed low values of antioxidant activities, whereas the methanolic fraction exhibited free radical scavenging activity ranging from 20.2% to 91.1%, and the inhibition of peroxidation values ranging from 5.6% to 27.5%. This is the first chemical study reported in the literature about this species. PMID:20726786

  3. Chemical constituents and antioxidant activity of the essential oil from leaves of Annona vepretorum Mart. (Annonaceae)

    Camila de Souza Araújo; Ana Paula de Oliveira; Rafaely Nascimento Lima; Péricles Barreto Alves; Tâmara Coimbra Diniz; Jackson Roberto Guedes da Silva Almeida

    2015-01-01

    Background: Annona vepretorum (AV) is a native tree from Caatinga biome (semiarid region of Brazil) popularly known as “araticum” and “pinha da Caatinga.” Objective: 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. Materials and Methods: Fresh leaves of AV were cut into pieces, and subjected to distillation for 2 h in a clevenger-type apparatus. Gas ch...

  4. Fungi as chemical industries and genetic engineering for the production of biologically active secondary metabolites

    Abid Ali Khan; Nafees Bacha; Bashir Ahmad; Ghosia Lutfullah; Umar Farooq; Russell John Cox

    2014-01-01

    Fungi is somewhere in between the micro and macro organisms which is a good source of producing biologically active secondary metabolites. Fungi have been used as tool for producing different types of secondary metabolites by providing different nutrients at different laboratory conditions. The fungi have been engineered for the desired secondary metabolites by using different laboratory techniques, for example, homologous and heterologous expressions. This review reported how the fungi are used as chemical industry for the production of secondary metabolites and how they are engineered in laboratory for the production of desirable metabolites;also the biosynthetic pathways of the bio-organic-molecules were reported.

  5. Fungi as chemical industries and genetic engineering for the production of biologically active secondary metabolites

    Abid; Ali; Khan; Nafees; Bacha; Bashir; Ahmad; Ghosia; Lutfullah; Umar; Farooq; Russell; John; Cox

    2014-01-01

    Fungi is somewhere in between the micro and macro organisms which is a good source of producing biologically active secondary metabolites.Fungi have been used as tool for producing different types of secondary metabolites by providing different nutrients at different laboratory conditions.The fungi have been engineered for the desired secondary metabolites by using different laboratory techniques,for example,homologous and heterologous expressions.This review reported how the fungi are used as chemical industry for the production of secondary metabolites and how they are engineered in laboratory for the production of desirable metabolites:also the biosynthetic pathways of the bio-organic-molecules were reported.

  6. Chemical composition and mosquito repellent activity of the essential oil of Plectranthus incanus link

    Pal Mahesh; Kumar Anil; Tewari Krishna Shri

    2011-01-01

    The chemical composition of the essential oil obtained from the leaves of Plectranthus incanus Link, with the yield of 0.6% (w/v), was analyzed by GC and GC/MS. A total of 16 constituents, representing 95.2% of the oil, were identified. The major components of the oil were fenchone (6.0%), piperitone oxide (32.4%), piperitenone (3.0%) and piperitenone oxide (41.5%). The repellent activity of the volatile oil at different concentrations was measured by the protection period against the b...

  7. Chemical Constituents from Andrographis echioides and Their Anti-Inflammatory Activity

    De-Yang Shen

    2012-12-01

    Full Text Available Phytochemical investigation of the whole plants of Andrographis echioides afforded two new 2'-oxygenated flavonoids (1 and (2, two new phenyl glycosides (3 and (4, along with 37 known structures. The structures of new compounds were elucidated by spectral analysis and chemical transformation studies. Among the isolated compounds, (1–2 and (6–19 were subjected into the examination for their iNOS inhibitory bioactivity. The structure-activity relationships of the flavonoids for their inhibition of NO production were also discussed.

  8. Chemical Composition of the Essential Oil from Croton oblongifolius and its Antibacterial Activity against Propionibacterium acnes.

    Athikomkulchai, Sirivan; Tadtong, Sarin; Ruangrungsi, Nijsiri; Hongratanaworakit, Tapanee

    2015-08-01

    The essential oil of C. oblongifolius Roxb. stem bark was obtained by hydrodistillation. Chemical analysis by GC-MS identified 29 compounds. Terpinen-4-ol (17.8%) was a major component, together with α-guaiene (7.9%), E-caryophyllene (7.0%), myrcene (6.7%), (+)-cyclosativene (5.1%), sabinene (4.8%), aciphyllene (4.7%), pogostol (4.6%), gamma-terpinene (3.4%), α-muurolol (3.2%) and germecrene D (3.2%). The essential oil exhibited antibacterial activity against Propionibacterium acnes ATCC 6919 with an MIC of 0.125%, v/v. PMID:26434141

  9. Tuning the chemical activity through PtAu nanoalloying: a first principles study

    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.

  10. Chemical Composition and Possible in Vitro Phytotoxic Activity of Helichrsyum italicum (Roth Don ssp. italicum

    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. Chemical composition and possible in vitro phytotoxic activity of Helichrsyum italicum (Roth) Don ssp. italicum.

    Mancini, Emilia; De Martino, Laura; Marandino, Aurelio; Scognamiglio, Maria Rosa; De Feo, Vincenzo

    2011-01-01

    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. PMID:21904272

  12. Studies on Medicago lupulina saponins. 6. Some chemical characteristics and biological activity of root saponins

    Wiesław Oleszek

    2014-02-01

    Full Text Available The saponin fraction of black medic trefoil (Medicago lupulina roots was isolated and purified. Its hydrolysis afforded several aglycones that have been identified by spectral and chemical properties as medicagenic acid, hederagenine and soyasapogenols: B, C, D, E and F. They made up, respectively. 46.9 and 45% of total sapogenins isolated. Two-dimensional TLC of M. lupulina root saponins revealed fourteen compounds, two of which were medicagenic acid glycosides. The haemolytic, antifungal and allelopathic activities of M. lupulina and M. media roots are compared and discussed.

  13. Chemical composition and antimicrobial activity of essential oils of Ocimum canum Sims. and Ocimum selloi Benth.

    Jeferson C. Nascimento; Luiz C. A. Barbosa; Vanderlucia F. Paula; David, Jorge M.; Renato Fontana; Luiz A.M. Silva; Robson S. França

    2011-01-01

    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,...

  14. Chemical composition and antimicrobial and antioxidant activities of Mentha (longifolia L. and viridis) essential oils.

    Mkaddem, Mounira; Bouajila, Jalloul; Ennajar, Monia; Lebrihi, Ahmed; Mathieu, Florence; Romdhane, Mehrez

    2009-09-01

    The study was aimed to investigate essential oil chemical composition (gas chromatography/flame ionization detection [GC-FID] and gas chromatography/mass spectrometry [GC-MS]) and antioxidant (1,1-diphenyl-2-picrylhydrazyl free radical (DPPH) and 2,2'-azinobis-3-ethylbenzothiazoline-6-sulphonate [ABTS] assays) and antimicrobial (Gram-positive and Gram-negative bacteria, fungi, and yeast) activities of essential oils extracted from leaves of Mentha longifolia L. and Mentha viridis. GC-MS analysis revealed that M. longifolia was constituted by pulegone (54.41%) as a major component followed by isomenthone (12.02%), 1,8-cineole (7.41%), borneol (6.85%), and piperitenone oxide (3.19%). M. viridis was rich in carvone (50.47%), 1,8-cineole (9.14%), and limonene (4.87%). The antioxidant activity by ABTS assay showed IC(50) values of 476.3 +/- 11.7 and 195.1 +/- 4.2 mg/L for M. longifolia and M. viridis, respectively, the DPPH assays have resulted in a moderate IC(50) (>8000 mg/L and 3476.3 +/- 133 mg/L for M. longifolia and M. viridis, respectively). Antimicrobial activity showed that Listeria monocytogenes and Klebsiella pneumoniae bacteria were more inhibited by the 2 essential oils tested. Escherichia coli was least susceptible. A strong activity was also observed on fungi and yeasts. Carvone, thymol, and piperitone oxide have not been detected in Tunisian M. longifolia. Camphor is reported for the 1st time for M. viridis. Antioxidant and antibacterial activities were correlated to chemical composition. PMID:19895481

  15. Essential Oil from the Resin of Protium heptaphyllum: Chemical Composition, Cytotoxicity, Antimicrobial Activity, and Antimutagenicity

    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

    Background: Protium heptaphyllum (Aubl.) March is popularly used as an analgesic and anti-inflammatory agent. Objective: 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. Materials and Methods: 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. Results: 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. Conclusion: The essential oil showed antimutagenic activity due to its chemical composition. SUMMARY 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

  16. First satellite measurements of chemical changes in coincidence with sprite activity

    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.

  17. Local electronic structure and photoelectrochemical activity of partial chemically etched Ti-doped hematite

    Rioult, Maxime; Belkhou, Rachid; Magnan, Hélène; Stanescu, Dana; Stanescu, Stefan; Maccherozzi, Francesco; Rountree, Cindy; Barbier, Antoine

    2015-11-01

    The direct conversion of solar light into chemical energy or fuel through photoelectrochemical water splitting is promising as a clean hydrogen production solution. Ti-doped hematite (Ti:α-Fe2O3) is a potential key photoanode material, which despite its optimal band gap, excellent chemical stability, abundance, non-toxicity and low cost, still has to be improved. Here we give evidence of a drastic improvement of the water splitting performances of Ti-doped hematite photoanodes upon a HCl wet-etching. In addition to the topography investigation by atomic force microscopy, a detailed determination of the local electronic structure has been carried out in order to understand the phenomenon and to provide new insights in the understanding of solar water splitting. Using synchrotron radiation based spectromicroscopy (X-PEEM), we investigated the X-ray absorption spectral features at the L3 Fe edge of the as grown surface and of the wet-etched surface on the very same sample thanks to patterning. We show that HCl wet etching leads to substantial surface modifications of the oxide layer including increased roughness and chemical reduction (presence of Fe2 +) without changing the band gap. We demonstrate that these changes are profitable and correlated to the drastic changes of the photocatalytic activity.

  18. Estrogen and androgen receptor activities of hydraulic fracturing chemicals and surface and ground water in a drilling-dense region

    Kassotis, Christopher D.; Tillitt, Donald E.; Davis, J. Wade; Hormann, Anette M.; Nagel, Susan C.

    2014-01-01

    The rapid rise in natural gas extraction using hydraulic fracturing increases the potential for contamination of surface and ground water from chemicals used throughout the process. Hundreds of products containing more than 750 chemicals and components are potentially used throughout the extraction process, including more than 100 known or suspected endocrine-disrupting chemicals. We hypothesized thataselected subset of chemicalsusedin natural gas drilling operationsandalso surface and ground water samples collected in a drilling-dense region of Garfield County, Colorado, would exhibit estrogen and androgen receptor activities. Water samples were collected, solid-phase extracted, and measured for estrogen and androgen receptor activities using reporter gene assays in human cell lines. Of the 39 unique water samples, 89%, 41%, 12%, and 46% exhibited estrogenic, antiestrogenic, androgenic, and antiandrogenic activities, respectively. Testing of a subset of natural gas drilling chemicals revealed novel antiestrogenic, novel antiandrogenic, and limited estrogenic activities. The Colorado River, the drainage basin for this region, exhibited moderate levels of estrogenic, antiestrogenic, and antiandrogenic activities, suggesting that higher localized activity at sites with known natural gas–related spills surrounding the river might be contributing to the multiple receptor activities observed in this water source. The majority of water samples collected from sites in a drilling-dense region of Colorado exhibited more estrogenic, antiestrogenic, or antiandrogenic activities than reference sites with limited nearby drilling operations. Our data suggest that natural gas drilling operationsmayresult in elevated endocrine-disrupting chemical activity in surface and ground water.

  19. Global CO2-consumption by chemical weathering: What is the contribution of highly active weathering regions?

    Hartmann, Jens; Jansen, Nils; Dürr, Hans H.; Kempe, Stephan; Köhler, Peter

    2010-05-01

    CO2-consumption by chemical weathering of silicates and resulting silicate/carbonate weathering ratios influences the terrestrial lateral inorganic carbon flux to the ocean and long-term climate changes. However, little is known of the spatial extension of highly active weathering regions and their proportion of global CO2-consumption. As those regions may be of significant importance for global climate change, global CO2-consumption is calculated here at high resolution, to adequately represent them. In previous studies global CO2-consumption is estimated using two different approaches: i) a reverse approach based on hydrochemical fluxes from large rivers and ii) a forward approach applying spatially explicit a function for CO2-consumption. The first approach results in an estimate without providing a spatial resolution for highly active regions and the second approach applied six lithological classes while including three sediment classes (shale, sandstone and carbonate rock) based at a 1° or 2° grid resolution. It remained uncertain, if the applied lithological classification schemes represent adequately CO2-consumption from sediments on a global scale (as well as liberation of other elements like phosphorus or silicon by chemical weatheirng). This is due to the large variability of sediment properties, their diagenetic history and the contribution from carbonates apparent in silicate dominated lithological classes. To address these issues, a CO2-consumption model, trained at high-resolution data, is applied here to a global vector based lithological map with 15 lithological classes. The calibration data were obtained from areas representing a wide range of weathering rates. Resulting global CO2-consumption by chemical weathering is similar to earlier estimates (237 Mt C a-1) but the proportion of silicate weathering is 63%, and thus larger than previous estimates (49 to 60%). The application of the enhanced lithological classification scheme reveals that it

  20. Chemical Composition and Antioxidant/Antimicrobial Activities in Supercritical Carbon Dioxide Fluid Extract of Gloiopeltis tenax

    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.

  1. Studies on Chemical Composition, Antimicrobial and Antioxidant Activities of Five Thymus vulgaris L. Essential Oils

    Emilia Mancini

    2015-07-01

    Full Text Available This study is aimed at assessing the essential oil composition, total phenolic content, antimicrobial and antioxidant activities of Thymus vulgaris collected in five different area of the Campania Region, Southern Italy. The chemical composition of the essential oils was studied by GC-flame ionization detector (FID and GC/MS; the biological activities were evaluated through determination of MIC and minimum bactericidal concentration (MBC and evaluation of antioxidant activity. In total, 134 compounds were identified. The oils were mainly composed of phenolic compounds, and all oils belonged to the chemotype thymol. The antimicrobial activity of the five oils was assayed against ten bacterial strains. The oils showed different inhibitory activity against some Gram-positive pathogens. The total phenol content in the essential oils ranged from 77.6–165.1 mg gallic acid equivalents (GAE/g. The results reported here may help to shed light on the complex chemotaxonomy of the genus Thymus. These oils could be used in many fields as natural preservatives of food and as nutraceuticals.

  2. Characterization of mesoporous carbon prepared from date stems by H3PO4 chemical activation

    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 (d200 and d100), stack height (Lc), stack width (La) 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, SBET, and total pore volume of 682, 1455, 1319 m2/g and 0,343, 1,045 and 0.735 cm3/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.

  3. Orange Peel Extracts: Chemical Characterization, Antioxidant, Antioxidative Burst, and Phytotoxic Activities.

    Erukainure, Ochuko L; Ebuehi, Osaretin A T; Iqbal Chaudhary, M; Mesaik, M Ahmed; Shukralla, Ahmed; Muhammad, Aliyu; Zaruwa, Moses Z; Elemo, Gloria N

    2016-01-01

    The search for novel drugs and alternative medicine has led to increased research in medicinal plants. Among such plants is the orange fruit. Its peels have been utilized for long as an active ingredient in most traditional medicines. This study aims at investigating the chemical properties of the hexane and dichloromethane (DCM) extracts of orange peel as well as their biological potentials. Blended peels were extracted with n-hexane and n-dichloromethane, respectively. The resulting extracts were subjected to gas chromatography mass spectrometry (GCMS) characterization. The extracts were also assayed for free radical scavenging ability against 1,1 -diphenyl -2 picrylhydrazyl (DPPH), antioxidative burst via measuring luminol -amplified chemiluminescence response in human blood, and phytotoxicity against lemna minor. GCMS analysis revealed a predominance of fatty acid methyl esters in the hexane extract, while the DCM extract had more ketone metabolites. The DCM extract had significant (p < .05) higher free radical scavenging and antioxidative burst activities compared to the hexane. Both extracts revealed a significantly (p < .05) high phytotoxicity activity. Results from this study indicated that solvent type played a vital a role in the extraction of secondary metabolites, which are responsible for the observed biological activities. The higher activities by the DCM extract can be attributed to its constituents as revealed by GCMS analysis. There is great need to explore the phytotoxicity potentials of both extracts as natural herbicides. PMID:26930349

  4. Chemical composition and antiprotozoal activities of Colombian Lippia spp essential oils and their major components.

    Escobar, Patricia; Milena Leal, Sandra; Herrera, Laura Viviana; Martinez, Jairo Rene; Stashenko, Elena

    2010-03-01

    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, gamma-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 microg/mL and 12.2 microg/mL, respectively. The essential oil of Lippia origanoides had an IC50 of 4.4 microg/mL in L. chagasi promastigotes and exhibited no toxicity in mammalian cells. Thymol (IC50 3.2 +/- 0.4 microg/mL) and S-carvone (IC50 6.1 +/- 2.2 microg/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. PMID:20428679

  5. Chemical composition and antiprotozoal activities of Colombian Lippia spp essential oils and their major components

    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.

  6. Chemical constituents and biological activities of Senecio aegyptius var. discoideus Boiss.

    Hassan, Wafaa; Al-Gendy, Amal; Al-Youssef, Hanan; El-Shazely, Assem

    2012-01-01

    A new eremophilane sesquiterpene, 1-beta-hydroxy-8-oxoeremophila-7,9-dien-12-oic acid (1), in addition to two known flavonol glycosides, rutin (2) and quercetin-3-O-glucoside-7-O-rutinoside (3), was isolated from the ethyl acetate fraction obtained from the aqueous alcoholic extract of the aerial parts of Senecio aegyptius var. discoideus Boiss. (family Asteraceae). The chemical structures of the isolated compounds were established by 1D and 2D NMR analysis (1H, 13C, COSY, HMQC, HMBC), MS and UV data, and through comparison with the literature. The ethyl acetate fraction and the isolated rutin showed significant cytotoxic activity against colorectal carcinoma (HCT 116) and to less extent against brain (U 251) and breast carcinoma (MCF 7). The ethyl acetate fraction showed a significant level of activity against Klebsiella pneumoniae, while the total extract showed the best antifungal activity against Candida albicans and Saccharomyces cerevisiae. DPPH radical scavenging activity of the ethyl acetate fraction was significant (96.7%) when compared to ascorbic acid. It also showed anti-inflammatory activity but no diuretic effect. PMID:22624330

  7. Chemical composition and antibacterial activity of selected essential oils and some of their main compounds.

    Wanner, Juergen; Schmidt, Erich; Bail, Stefanie; Jirovetz, Leopold; Buchbauer, Gerhard; Gochev, Velizar; Girova, Tanya; Atanasova, Teodora; Stoyanova, Albena

    2010-09-01

    The chemical composition of essential oils of cabreuva (Myrocarpus fastigiatus Allemao, Fabaceae) from Brazil, cedarwood (Juniperus ashei, Cupressaceae) from Texas, Juniper berries (Juniperus communis L., Cupressaceae) and myrrh (Commiphora myrrha (Nees) Engl., Burseraceae) were analyzed using GC/FID and GC/MS. The antimicrobial activity of these essential oils and some of their main compounds were tested against eleven different strains of Gram-positive and Gram-negative bacteria by using agar diffusion and agar serial dilution methods. Animal and plant pathogens, food poisoning and spoilage bacteria were selected. The volatile oils exhibited considerable inhibitory effects against all tested organisms, except Pseudomonas, using both test methods. Higher activity was observed against Gram-positive strains in comparison with Gram-negative bacteria. Cabreuva oil from Brazil showed similar results, but in comparison with the other oils tested, only when higher concentrations of oil were used. PMID:20922991

  8. Activity-based chemical proteomics accelerates inhibitor development for deubiquitylating enzymes.

    Altun, Mikael; Kramer, Holger B; Willems, Lianne I; McDermott, Jeffrey L; Leach, Craig A; Goldenberg, Seth J; Kumar, K G Suresh; Konietzny, Rebecca; Fischer, Roman; Kogan, Edward; Mackeen, Mukram M; McGouran, Joanna; Khoronenkova, Svetlana V; Parsons, Jason L; Dianov, Grigory L; Nicholson, Benjamin; Kessler, Benedikt M

    2011-11-23

    Converting lead compounds into drug candidates is a crucial step in drug development, requiring early assessment of potency, selectivity, and off-target effects. We have utilized activity-based chemical proteomics to determine the potency and selectivity of deubiquitylating enzyme (DUB) inhibitors in cell culture models. Importantly, we characterized the small molecule PR-619 as a broad-range DUB inhibitor, and P22077 as a USP7 inhibitor with potential for further development as a chemotherapeutic agent in cancer therapy. A striking accumulation of polyubiquitylated proteins was observed after both selective and general inhibition of cellular DUB activity without direct impairment of proteasomal proteolysis. The repertoire of ubiquitylated substrates was analyzed by tandem mass spectrometry, identifying distinct subsets for general or specific inhibition of DUBs. This enabled identification of previously unknown functional links between USP7 and enzymes involved in DNA repair. PMID:22118674

  9. Antimicrobial Activity and Chemical Constituents of the Extract from Jatropha curcas Fruit

    Kanda Saosoong

    2016-05-01

    Full Text Available The antimicrobial activity and chemical constituents of the methanolic extract from J. curcas fruit were evaluated in this study. The crude extract was achieved by extraction with 60 % (v/v methanol. It showed the potencies of antimicrobial activity against P. putida, P. syringae pv. sesami, X. campestris, X. campestris pv. glycines, X. campestris pv. vesicatoria and R. solanacearum with the presence of inhibition zone in the range of 8.0 ± 0.0 to 13.7 ± 0.6 mm and MIC value at 214.29 ± 0.00 mg/mL. Furthermore, flavone compound can be proposed by the analysis of gas chromatography-mass spectrometry (GC-MS. According to the group of flavonoid compounds have strong bioactive properties; the results suggested that J. curcas fruit has highly potential as effective natural bioactive sources.

  10. Supercritical CO2 extract of Cinnamomum zeylanicum: chemical characterization and antityrosinase activity.

    Marongiu, Bruno; Piras, Alessandra; Porcedda, Silvia; Tuveri, Enrica; Sanjust, Enrico; Meli, Massimo; Sollai, Francesca; Zucca, Paolo; Rescigno, Antonio

    2007-11-28

    The volatile oil of the bark of Cinnamomum zeylanicum was extracted by means of supercritical CO2 fluid extraction in different conditions of pressure and temperature. Its chemical composition was characterized by GC-MS analysis. Nineteen compounds, which in the supercritical extract represented >95% of the oil, were identified. (E)-Cinnamaldehyde (77.1%), (E)-beta-caryophyllene (6.0%), alpha-terpineol (4.4%), and eugenol (3.0%) were found to be the major constituents. The SFE oil of cinnamon was screened for its biological activity about the formation of melanin in vitro. The extract showed antityrosinase activity and was able to reduce the formation of insoluble flakes of melanin from tyrosine. The oil also delayed the browning effect in apple homogenate. (E)-Cinnamaldehyde and eugenol were found to be mainly responsible of this inhibition effect. PMID:17966976

  11. Chemical Composition, Antioxidant and Antimicrobial Activity of Pericarpium Citri Reticulatae Essential Oil

    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.

  12. Chemical composition and antimicrobial activity of peppermint (Mentha piperita L. Essential oil

    Mohaddese Mahboubi

    2014-02-01

    Full Text Available Peppermint with antiseptic and known healing properties is a plant from the Labiatae family. In this study, we analyzed the chemical composition of essential oil from the flowering aerial part of peppermint by GC and GC/MS. Its antimicrobial activity was evaluated against bacteria, fungi and yeast by micro broth dilution assay. The fractional inhibitory concentration (FIC and FIC Index (FICI and related isobologram curve were determined by check board micro titer assay. The results exhibited that the MIC, MLC value of peppermint oil against different kinds of microorganisms were in the range of 0.125-2 and 0.125- >64 µl/ml, respectively. Candida albicans was the most sensitive microorganism and Pseudomonas aeruginosa was the less sensitive ones. The oil showed synergistic activities with vancomycin, gentamycin, and amphotericin B with the FICI less of 0.5. This oil could be used as natural antibiotics and may decrease the effective dose of antibiotics.

  13. Chemical composition of soils in the areas of volcanic ashfalls around active volcanoes in Kamchatka

    Zakharikhina, L. V.; Litvinenko, Yu. S.

    2016-03-01

    The geochemical features of volcanic soils (Andosols) in the northern soil province of Kamchatka are identified. The background regional concentrations ( Cb r ) of most of chemical elements in the studied soils are lower than their average concentrations in soils of the world and in the European volcanic soils. Only Na, Ca, and Mg are present in elevated concentrations in all the studied soils in the north of Kamchatka. Regional background concentrations of elements are exceeded by 1.6 times in the area of active ashfalls of the Tolbachik volcano and by 1.3 times in the area of active ashfalls of the Shiveluch volcano. The concentrations of mobile forms of elements in these areas exceed their regional background concentrations by 2.1 and 2.6 times, respectively.

  14. Features of the vacuum activated thermo-chemical treatment of materials

    In this study the option of a heat-resistant layer is approved for protecting products from niobium was tested and based on silicides of molybdenum and niobium. Coating was formed by method of vacuum diffusion saturation in presence vapors of sodium chloride. As the saturating environment was used mixture, consisting of powders disilicide of molybdenum, silicon and alloying additions. The thermodynamics calculation of possible chemical reactions was executed for determination of components saturation environment of gas and terms transfer of molybdenum in niobium. Niobium samples were siliconized at the temperature of T = 1250 oN within 7 hours and stream activator 1 g/hour. The coating consisted of two layers, thickness upper layer - 90 mkm, adjoining to basis - 10 mkm. Also the process of vacuum- activated boriding of steel 45 was investigated.

  15. Chemical Constituents of Jacaranda oxyphylla and their Acetylcholinesterase Inhibitory and Antimicrobial Activities

    Vinicius Viana Pereira

    2015-10-01

    Full Text Available This study evaluated chemical composition of Jacaranda oxyphylla, acetylcholinesterase inhibitory and antimicrobial activities of the isolated compounds. Phytochemical investigation of leaves extract yielded three classes of substances: fatty compounds, sterols and triterpenes. Butyl hexadecanoate (1, fatty alcohol (2, 2-(4-hydroxyphenylethyl triacontanoate (3, β -sitosterol (4, sitosterol-3-O- β- D -glucoside (5, 6'-palmitoyl-sitosterol-3-O- β- D -glucoside (6, oleanolic acid (7, ursolic acid (8 and corosolic acid (9 were obtained from n-hexane, CHCl 3 and EtOH extracts of J. oxyphylla. It was found a pronounced acetylcholinesterase inhibitory activity for the fatty compounds 1-3 and sterols 5 and 6, with values between 60 to 77%. Substances 7-9 presented a high antibacterial action against Bacillus cereus and Salmonella typhimurium, with values of growth inhibition in the range of 84 to 90%.

  16. Antioxidant activity and chemical composition of three Tunisian Cistus: Cistus monspeliensis, Cistus villosus and Cistus libanotis.

    Nicoletti, Marcello; Toniolo, Chiara; Venditti, Alessandro; Bruno, Maurizio; Ben Jemia, Mariem

    2015-02-01

    The chemical composition of three rockrose Cistus species, Cistus monspeliensis, Cistus libanotis and Cistus villosus, collected in Tunisia, was studied by HPTLC, focusing on the terpenes and phenols constituents. Diterpenes of Cistus are important as the main constituents of the leaf sticky aromatic resin, known as labdanum, which are highly appreciated in perfumery. Polyphenols in the methanolic extracts of each species were identified, quantified as total and as flavonoids and tannins, and tested for antioxidant activity. Diterpenes were evident in C. libanotis and C. monspeliensis, whereas they were practically absent in C. villosus; C. libanotis had higher phenolic amount, whereas antioxidant activities were important, but different according to the following tests: DPPH radical scavenging, conversion of the Fe(3+/)ferricyanide complex and inhibition of β-carotene bleaching. The reported data confirm the validity of utilisation of Cistus sp. in marketed herbal products, as well as the relevant presence of diterpenes in species actually not used for labdanum production. PMID:25116860

  17. Chemical composition and antibacterial activity of essential oil of Nepeta graciliflora Benth. (Lamiaceae).

    Sharma, Pankaj; Shah, G C; Sharma, Rabia; Dhyani, Praveen

    2016-06-01

    The chemical composition of the essential oil obtained from aerial parts of Nepeta graciliflora was analysed, for the first time, by GC-FID and GC-MS. A total of 27 compounds were identified, constituting over 91.44% of oil composition. The oil was strongly characterised by sesquiterpenes (86.72%), with β-sesquiphellandrene (28.75%), caryophyllene oxide (12.15%), α-bisabolol (8.97%), α-bergamotene (8.51%), β-bisabolene (6.33%) and β-Caryophyllene (5.34%) as the main constituents. The in vitro activity of the essential oil was determined against four micro-organisms in comparison with chloramphenicol by the agar well diffusion and broth dilution method. The oil exhibited good activity against all tested organisms. PMID:26140331

  18. Toxicity challenges in environmental chemicals: Prediction of human plasma protein binding through quantitative structure-activity relationship (QSAR) models

    The present study explores the merit of utilizing available pharmaceutical data to construct a quantitative structure-activity relationship (QSAR) for prediction of the fraction of a chemical unbound to plasma protein (Fub) in environmentally relevant compounds. Independent model...

  19. Chemical composition and biological activity of essential oils of Dracocephalum heterophyllum and Hyssopus officinalis from Western Himalaya

    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...

  20. Determination of antibacterial, antifungal activity and chemical composition of essential oil portion of unani formulation kulzam

    K Ashok Kumar

    2011-01-01

    Full Text Available Kulzam is a popular unani, liquid formulation; indicated for several minor ailments like cough, cold, running nose, sore throat, insect bites, earache, tooth ache, etc. by the manufacturer. However, this over the counter formulation has not been scientifically evaluated for its claimed uses. Hence in the present study an attempt has been to check the chemical composition, antibacterial and antifungal activity as most of the above-mentioned conditions are underpinned by microbial activity. The antibacterial and antifungal activity of the formulation was carried out on human pathogenic bacteria Pseudomonas aerogenousa, Escherichia coli, Staphylococcus aureus, Corynebacterium and fungi Candida albicans, Aspergillus fumigates and was compared with standards ciprofloxacin and clotrimazole. Kulzam exhibited strong in vitro inhibition of growth against all the test micro-organisms at both 100 and 150 μl levels of undiluted formulation (test sample and more than that of standard at 150 μl level. The chemical composition of essential oil of the formulation was determined by gas chromatography−mass spectroscopy (GC-MS analysis. Thirteen compounds constituting about 93.56% of the essential oil were identified. The main components were Camphor, menthol, thymol, 2-propenal 3-phenyl-, eugenol, trans-caryophyllene, p-allylanisole, linalool, eucalyptol, l-limonene, 1-methyl-2-isopropylbenzene, and 1S-alpha-pinene. The outcome of this study shows that kulzam contain terpenes and their oxygenated derivatives, which are believed to be highly effective antibacterial, antifungal, analgesic, anti-inflammatory, antioxidant, spasmolytic and immunomodulatory agents. The formulation has been found to possess strong antibacterial and antifungal properties, and it becomes very difficult to pin point the specific compound responsible for studied activities. However, the study positively motivates the use of kulzam for common ailments.

  1. Determination of chemical elements in Eucalyptus grandis, manured with Ballad's, by neutrons activation analysis

    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)

  2. Antidiabetic activity of the chemical constituents of Combretum dolichopetalum root in mice

    Uzor, Philip F.; Osadebe, Patience O.

    2016-01-01

    The root of Combretum dolichopetalum (Combreatacea) is used in ethnomedicine for the management of diabetes mellitus. Though some compounds have been isolated from it, the antidiabetic principles have not been identified. The present study was designed to evaluate the chemical constituents from the root of C. dolichopetalum with a view to identifying the antidiabetic principles. The constituents include the alkaloids, echinulin (1) and arestrictin B (2), the terpenoids, arjunolic acid (3) and 4'-dihydrophaseic acid (4) as well as the phenolic acids, ellagic acid (5) and 3, 4, 3'-tri-O-methylellagic acid (6). Twenty eight mice (in seven groups, n = 4) were made diabetic using alloxan monohydrate (i.p., 120 mg/kg) and treated orally with either the vehicle (control group), any of the constituents or glibenclamide (standard drug). The fasting blood glucose of the diabetic animals was monitored for nine hours. Results showed that all the chemical constituents (1-6) exhibited significant (p < 0.05) antidiabetic activity comparable to glibenclamide. The alkaloids exhibited the most profound antidiabetic activity. The present study has thus identified the antidiabetic principles of C. dolichopetalum root as echinulin, arestrictin B, arjunolic acid, 4'-dihydrophaseic acid, ellagic acid and 3, 4, 3'-tri-O-methylellagic acid. The study has further validated the ethnomedicinal use of the root of C. dolichopetalum in diabetes. PMID:27298614

  3. Biological effects of activation products and other chemicals released from fusion power plants

    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 26Al, 49V, 51Cr, 54Mn, 55Fe, 58Co, 60Co, 93Nb, and 94Nb. 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

  4. Antirheumatoid Arthritis Activities and Chemical Compositions of Phenolic Compounds-Rich Fraction from Urtica atrichocaulis, an Endemic Plant to China

    Mengyue Wang; Ke Li; Yuxiao Nie; Yingfang Wei; Xiaobo Li

    2012-01-01

    Urtica atrichocaulis, an endemic plant to China, is commonly used to treat rheumatoid arthritis even though its pharmaceutical activities and chemical constituents were not studied. Herein, we reported our investigations on the chemical compositions of the phenolic compounds-rich fraction from U. atrichocaulis (TFUA) and their antirheumatoid arthritis activities. We found that the TFUA significantly inhibited the adjuvant-induced rats arthritis, carrageenin-induced rats paw edema, cotton pell...

  5. Chemical Composition and In Vitro Antibacterial Activity of Mentha spicata Essential Oil against Common Food-Borne Pathogenic Bacteria

    Yasser Shahbazi

    2015-01-01

    The aim of the present study was to investigate chemical composition and antibacterial activity of essential oil from the leaf of Mentha spicata plant against common food-borne pathogenic bacteria (Staphylococcus aureus, Bacillus subtilis, Bacillus cereus, Listeria monocytogenes, Salmonella typhimurium, and Escherichia coli O157:H7). Chemical composition of the essential oil was identified by gas chromatography coupled with mass spectrometer detector (GC-MS). The antibacterial activity of the...

  6. Chemical Composition of Propolis from Different Regions in Java and their Cytotoxic Activity

    Syamsudin

    2009-01-01

    Full Text Available Problem statement: Propolis samples from tropical zones, such as Java (Indonesia with its vast biodiversity, have become a subject of increasing scientific and economic attention. The association of the chemical composition of propolis from different geographic regions with cytotoxic activities lead to the identification of active principles, a fundamental tool to achieve standardization of this bee product. Approach: The purpose of this research was evaluate the quality of propolis collected at different places in Java (Indonesia based on cytotoxic activity. The ethanolic extracts of propolis from different areas in Java were tested for cytotoxicity against tumor cell lines (T47D, MCF-7, Hela, Myeloma and Vero using MTT assay. Propolis samples were collected from Batang (Central Java, Lawang (East Java and Sukabumi (West Java. Results: The extract of propolis from Batang showed the most potent activity of T47D and MCF-7 with IC50 34.67±8.3 and 37.8±.5 µg mL-1. The extract of propolis from Sukabumi showed the most potent activity of Hela cell with IC50 147.34±8.9. However, all propolis extract did not show activity of myeloma and Vero cells. Conclusion: Ethanolics extract of three propolis samples from Batang (Central Java, Lawang (East Java and Sukabumi (West Java regions in Java were investigated using GC-MS. From 37 compounds identified, 7 among of them were found for the first time in propolis. This indicated that the secondary metabolite extract of propolis from Batang (Central Java obtained in the study has antiproliferative activity of breast carcinoma cells (T47D and MCF-7.

  7. Activation of chemical biological defense mechanisms and remission of vital oxidative injury by low dose radiation

    Yamaoka, K. [Okayama University Medical School, Okayama (Japan); Nomura, T. [Central Research Institute of Electric Power Industry, Tokyo (Japan); Kojima, S. [Science University of Tokyo, Chiba (Japan)

    2000-05-01

    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 {alpha}-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{sub 2}- to H{sub 2}O{sub 2}, the question as to whether the resultant H{sub 2}O{sub 2} is further detoxicated into H{sub 2}O and O{sub 2} or not must

  8. Activation of chemical biological defense mechanisms and remission of vital oxidative injury by low dose radiation

    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 O2- to H2O2, the question as to whether the resultant H2O2 is further detoxicated into H2O and O2 or not must still be evaluated. Hence, we studied the effect of

  9. Chemical constituents of Phragmanthera austroarabica A. G. Mill and J. A. Nyberg with potent antioxidant activity

    Jihan M Badr

    2015-01-01

    Full Text Available Background: Phragmanthera austroarabica A.G. Mill. and J. A. Nyberg is a semi parasitic plant belonging to family Loranthaceae. It was collected from Saudi Arabia. It is widely used in folk medicine among the kingdom in treatment of various diseases including diabetes mellitus. Objective: The total alcoholic extract of P. austroarabica collected from Saudi Arabia was investigated for the chemical structure and prominent biological activity of the main constituents. Materials and Methods: Isolation of the active constituents was performed using different chromatographic techniques including column chromatography packed with silica or sephadex and preparative thin layer chromatography. The structures of the isolated compounds were established based on different spectroscopic data as mass spectrum, one-dimensional and two-dimensional nuclear magnetic resonance (correlation spectroscopy, heteronuclear single quantum coherence, and heteronuclear multiple-bond correlation. Results: Phytochemical investigation of the plant resulted in isolation of 12 compounds. The isolated compounds were identified as chrysophanic acid, emodin, chrysophanic acid-8-O-glucoside, emodin-8-O-glucoside, pectolinarigenin, quercetin, dillenetin-3-O-glucoside, catechin, catechin-4′-O-gallate, methyl gallate, lupeol and ursolic acid. All the isolated phenolic compounds revealed significant free radical scavenging activities when tested using 2,2-diphenyl-1-picrylhydrazyl reagent. Conclusion: The antioxidant activities of the isolated compounds can justify the use of P. austroarabica in traditional medicine for treatment of diabetes and verify its possible application as an antihyperglycemic drug.

  10. [Chemical constituents from stems of Hedyotis hedyotidea and their immunosuppressive activity].

    Zhang, Tian-tian; Gao, Sha-sha; Hou, Jun-jie; Zhou, Yong-qin; Zhou, Jie-wen; Wang, Xiao-gang; Qin, Nan; Chen, Jia-chun; Duan, Hong-quan; Fang, Jin-bo

    2015-06-01

    Hedyotis hedyotidea has been traditionally used for the treatment of arthritis, cold, cough, gastro-enteritis, headstroke, etc. But few studies have screened the active compounds from extracts of H. hedyotidea. In this study, the structure of the chemical constituents from stems of H. hedyotidea were determined and the immunosuppressive activity of the compounds was evaluated. The compounds were separated and purified with silica gel, gel column chromatographies and preparative HPLC, and their structures were identified by spectral methods such as MS and NMR. Eleven compounds were obtained and identified as(6S,9S) -vomifoliol (1), betulonic acid (2), betulinic acid (3), betulin(4), 3-epi-betulinic acid (5), ursolic acid (6), β-sitosterol (7), stigmast-4-en-3-one (8), 7β-hydroxysitosterol (9), (3β,7β) -7-methoxystigmast-5-en-3-ol (10) and morindacin (11). This is the first report of compounds 1, 2, 4, 8, 9, 10 and 11 from H. hedyotidea. Compounds 1, 2 and 8-11 were firstly isolated from the genus Hedyotis, and compounds 9 and 10 were isolated from the family Rubiaceae for the first time. The immunosuppressive activity of these compounds was tested using the lymphocyte transsormationtest. Compounds 4, 6 and 9 showed significant immunosuppressive activity. PMID:26591525

  11. Ethnobotany, chemical constituents and biological activities of the flowers of Hydnora abyssinica A.Br. (Hydnoraceae).

    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. PMID:27209704

  12. Antidiabetic activity and chemical constituents of the aerial parts of Heracleum dissectum Ledeb.

    Zhang, Hailong; Su, Yaping; Wang, Xinrui; Mi, Jie; Huo, Yayu; Wang, Zhigang; Liu, Ying; Gao, Yang

    2017-01-01

    Heracleum dissectum Ledeb. has long been used as a wild edible vegetable by local people in China. The purpose of this study is to investigate the antidiabetic potential of aerial part of H. dissectum methanol extract (HdME) and the chemical constituents. Ten compounds including eight coumarins were isolated and four of them were found from H. dissectum for the first time. HdME potently inhibited the elevation of plasma glucose after its oral administration to glucose-loaded mice, and its petroleum ether (PE) fraction exerted the greatest inhibitory activities. Meanwhile, HdME (125 and 250mg/kg) also significantly decreased the blood glucose level in STZ-induced diabetic mice, but had no effect in normoglycemic mice. Additionally, HdME showed weak inhibitory effects on α-glucosidase activity and DPPH free radicals scavenging. In conclusion, HdME has antidiabetic action and PE fraction is the active part where coumarins possibly play an important role in antidiabetic activity. PMID:27507512

  13. Chemical activation in view of MSWI bottom ash recycling in cement-based systems.

    Polettini, A; Pomi, R; Fortuna, E

    2009-03-15

    In the present study, the feasibility of recycling incinerator bottom ash in cementitious systems by means of chemical activation was investigated. Different Na-, K- and Ca-based hydroxides and salts were selected for the experiments on the basis of their recognized effects on activation of typical pozzolanic materials. The evolution of mechanical properties of bottom ash/Portland cement mixtures and the leaching of trace metals from the materials were a matter of major concern. The experiments were arranged according to a full factorial design, which also allowed to derive a predictive model for unconfined compressive strength as affected by bottom ash content as well as activator type and dosage. Among the activators tested, calcium chloride was found to affect mechanical strength far more positively than the other species used, at the same time ensuring low metal release from the material. On the other hand, the use of potassium sulfate was observed to cause a significant increase in metal leaching at pHettringite as soon as it converted into monosulfate over time. PMID:18632208

  14. Computer-controlled, chemical separation system for use with neutron-activated samples

    Neutron activation analysis has proven to be a sensitive technique for the quantitative determination of metals in the parts-per-billion range. While sodium and potassium salt concentrations in sea water and biological materials are on the order of 10,000 ppm, the levels of trace metals range from 1 ppm to 0.1 ppb. The high concentrations and high activities of the salts in these matrices greatly reduce the ability to measure short half-life isotopes such as 2.3 min. 28Al, 3.8 min. 52V and 5.1 min. 66Cu. Post-irradiation separation is often the method of choice for such samples. However, when performed manually this technique is awkward, slow and unsafe. The Basic Automated Separation System (BASS) is a computer-controlled, chemical separation system for use in post-irradiation separations of neutron activated samples. It allows irradiation and separation of high-activated samples without user-intervention

  15. Chemical Composition and Nematicidal Activity of Essential Oil of Agastache rugosa against Meloidogyne incognita

    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.

  16. Chemical composition and biological activity of essential oil from Pulicaria undulata from Yemen.

    Ali, Nasser A Awadh; Sharopov, Farukh S; Alhaj, Mehdi; Hill, Gabrielle M; Porzel, Andrea; Arnold, Norbert; Setzer, William N; Schmidt, Jürgen; Wessjohann, Ludger

    2012-02-01

    The chemical composition of the essential oil obtained from the leaves of Pulicaria undulata Gamal Ed Din (syn P. orientalis sensu Schwartz and P. jaubertii Gamal Ed Din) was analyzed by GC-MS. Major compounds of P. undulata oil were the oxygenated monoterpenenes, carvotanacetone (91.4%) and 2,5-dimethoxy-p-cymene (2.6.%). The antimicrobial activity of the essential oil was evaluated against six microorganisms, Escherichia coli Pseudomonas aeruginosa, Staphylococcus aureus, methicillin-resistant S. aureus, Bacillus subtilis, and Candida albicans, using disc diffusion and broth microdilution methods. The oil showed the strongest bactericidal activity against Staphylococcus aureus and methicillin-resistant S. aureus, as well as Candida albicans. The essential oil showed moderate cytotoxic activity against MCF-7 breast tumor cells, with an IC50 of 64.6 +/- 13.7 microg/mL. Bioautographic assays were used to evaluate the acetylcholinesterase inhibitory effect as well as antifungal activity of the oil against Cladosporium cucumerinum. PMID:22474974

  17. Chemical composition and biological activities of essential oils of Azadirachta indica A. Juss.

    S S El-Hawary

    2013-09-01

    Full Text Available Summary. Essential oils of Neem, Azadirachta indica A. Juss. (family Meliaceae leaves and flowers were prepared by hydrodistillation method. The chemical composition of the oil samples was investigated by GC/MS. Hydrocarbon constituted 85.36% of the leaves oil .The major compounds were β-Elemene (33.39%, γ- Elemene (9.89%, Germacrene D (9.72%, Caryophyllene (6.8% and Bicyclogermacrene (5.23% while the percent of the oxygenated compounds were (5.04% mainly attributed to sesquiterpene oxide. On the other hand, flowers oil hydrocarbons constituted 63.22% composed mainly of pentacosane (18.58%, tetracosane (10.65%, β-germacrene (9.73%, β- caryophyllene (5.84% and dodecene (4.54% while the percent of the oxygenated compounds were 28.3% mainly attributed to octadecanol (16.7%, verdiflorol (5.32%, farnesol (1.63% and α– terpineol (1.51%. The antioxidant properties determined by 2, 2-diphenyl-1-picrylhydrazyl assays, antibacterial activity against Gram-positive and Gram-negative, antifungal and larvicidal activities were promising and in relation with the chemical composition of the essential oils. The results indicated that essential oil of flowers could be especially promising as an inexpensive source of effective antioxidant /antimicrobial /larvicidal agents tantamount to fixed oil of the neem seeds.Industrial relevance. The use of medicinal plants is a universal phenomenon. Natural products from plants are rich source to identify, select and process new drugs for medicinal use. Most of research focused on fixed oil of neem seeds but very little was concerned about volatile oils of leaves and flowers. The diverse biological activities of Neem essential oils can be applied on a large scale as antioxidant, antimicrobial and larvicidal agents comprising many important benefits including their volatility, lower level of risk to the environment than with synthetic ones.Keywords. Azadirachta indica; Neem; essential oil; GC/MS; antioxidant

  18. A Study on an Executive Technique and Activation of Clean Production in Chemical Industry

    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.

  19. Antioxidant Activity of Caffeic Acid against Iron-Induced Free Radical Generation--A Chemical Approach.

    Thiago C Genaro-Mattos

    Full Text Available Caffeic acid (CA is a phenolic compound widely found in coffee beans with known beneficial effects in vivo. Many studies showed that CA has anti-inflammatory, anti-mutagenic, antibacterial and anti-carcinogenic properties, which could be linked to its antioxidant activity. Taking in consideration the reported in vitro antioxidant mechanism of other polyphenols, our working hypothesis was that the CA antioxidant activity could be related to its metal-chelating property. With that in mind, we sought to investigate the chemical antioxidant mechanism of CA against in vitro iron-induced oxidative damage under different assay conditions. CA was able to prevent hydroxyl radical formation promoted by the classical Fenton reaction, as determined by 2-deoxyribose (2-DR oxidative degradation and DMPO hydroxylation. In addition to its ability to prevent hydroxyl radical formation, CA had a great inhibition of membrane lipid peroxidation. In the lipid peroxidation assays CA acted as both metal-chelator and as hydrogen donor, preventing the deleterious action promoted by lipid-derived peroxyl and alkoxyl radicals. Our results indicate that the observed antioxidant effects were mostly due to the formation of iron-CA complexes, which are able to prevent 2-DR oxidation and DMPO hydroxylation. Noteworthy, the formation of iron-CA complexes and prevention of oxidative damage was directly related to the pH of the medium, showing better antioxidant activity at higher pH values. Moreover, in the presence of lipid membranes the antioxidant potency of CA was much higher, indicating its enhanced effectiveness in a hydrophobic environment. Overall, our results show that CA acts as an antioxidant through an iron chelating mechanism, preventing the formation of free hydroxyl radicals and, therefore, inhibiting Fenton-induced oxidative damage. The chemical properties of CA described here--in association with its reported signaling effects--could be an explanation to its

  20. Chemical Analysis and Biological Activity of the Essential Oils of Two Endemic Soqotri Commiphora Species

    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.

  1. 75 FR 69630 - Impact of Implementation of the Chemical Weapons Convention on Commercial Activities Involving...

    2010-11-15

    ... Bureau of Industry and Security Impact of Implementation of the Chemical Weapons Convention on Commercial... implementation of the Chemical Weapons Convention (CWC), through the Chemical Weapons Convention Implementation Act (CWCIA) and the Chemical Weapons Convention Regulations (CWCR), has had on commercial...

  2. 77 FR 75145 - Impact of the Implementation of the Chemical Weapons Convention (CWC) on Commercial Activities...

    2012-12-19

    ... Bureau of Industry and Security Impact of the Implementation of the Chemical Weapons Convention (CWC) on... implementation of the Chemical Weapons Convention (CWC), through the Chemical Weapons Convention Implementation Act (CWCIA) and the Chemical Weapons Convention Regulations (CWCR), has had on commercial...

  3. Chemical composition, antioxidative and antimicrobial activity of essential oil Ocimum sanctum L.

    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.

  4. Disposal of chemical agents and munitions stored at Umatilla Depot Activity, Hermiston, Oregon

    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.

  5. Agrice 1994-2000 - Activity report. Agriculture for chemicals and energy

    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

  6. Responses to chemical cues from animal and plant foods by actively foraging insectivorous and omnivorous scincine lizards.

    Cooper, W E; Al-Johany, A M; Vitt, L J; Habegger, J J

    2000-10-01

    If tongue-flicking is important to lizards to sample chemical cues permitting identification of foods, tongue-flicking and subsequent feeding responses should be adjusted to match diet. This hypothesis can be examined for plant foods because most lizards are insectivores, but herbivory/omnivory has evolved independently in many lizard taxa. Here we present experimental data on chemosensory responses to chemical cues from animal prey and palatable plants by three species of the scincine lizards. When tested with chemical stimuli presented on cotton swabs, the insectivorous Eumeces fasciatus responded strongly to prey chemicals but not to chemicals from plants palatable to omnivorous lizards or to pungent or odorless control stimuli. Two omnivorous species, E. schneideri and Scincus mitranus, responded more strongly to chemical cues from both prey and food plants than to the control chemicals. All available data for actively foraging lizards, including these skinks, show that they are capable of prey chemical discrimination, and insectivores do not exhibit elevated tongue-flicking or biting responses to chemical cues from palatable plants. In all of the several species of herbivores/omnivores tested, the lizards show elevated responses to both animal and plant chemicals. We suggest two independent origins of both omnivory and plant chemical discrimination that may account for the evolution of diet and food chemical discriminations in the eight species of skinks studied, five of which are omnivores. All data are consistent with the hypothesis that acquisition of omnivory is accompanied by acquisition of plant chemical discrimination, but data on a broad diversity of taxa are needed for a definitive comparative test of the evolutionary hypothesis. J. Exp. Zool. 287:327-339, 2000. PMID:10980491

  7. Chemical stress induced by heliotrope (Heliotropium europaeum L.) allelochemicals and increased activity of antioxidant enzymes.

    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. PMID:18814656

  8. Chemical characterization of diets consumed in the COSEAS restaurant, by neutron activation analysis

    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 1566b), 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)

  9. Current activities of chemical applications of Tsing Hua Open-pool Reactor

    Tsing Hua Open-pool Reactor (THOR) is a swiming pool type research reactor operated and maintained by the University. The functions of THOR are two folds, i.e. (1) teaching and training of nuclear scientists and engineers, and (2) promotion of peaceful uses of atomic energy in Taiwan. Thus, besides the educational program THOR has been offering neutron irradiation service on regular schedule (30 hrs. per week full power operation at 1 MW with neutron flux of ca. 2 x 1012 n cm-2 sec.-1 since 1963). Among many other projects chemical application of THOR has been one of the important program implimented in early days. Following two projects have been set up with rather limited budget: (1) Production and supply of short-lived radioisotopes (both general purpose and medical use) for domestic use. (2) Application of neutron activation analysis in the fields of environmental, geological, biological and material science. It turned out that quite fruitful results have been obtained. It is the purpose of this paper to describe in detail some of the characteristic aspects on the utilization of THOR in the field of chemical application. (author)

  10. CHEMICAL ACTIVATION OF MOLECULES BY METALS: EXPERIMENTAL STUDIES OF ELECTRON DISTRIBUTIONS AND BONDING

    LICHTENBERGER, DENNIS L.

    2002-03-26

    This research program is directed at obtaining detailed experimental information on the electronic interactions between metals and organic molecules. These interactions provide low energy pathways for many important chemical and catalytic processes. A major feature of the program is the continued development and application of our special high-resolution valence photoelectron spectroscopy (UPS), and high-precision X-ray core photoelectron spectroscopy (XPS) instrumentation for study of organometallic molecules in the gas phase. The study involves a systematic approach towards understanding the interactions and activation of bound carbonyls, C-H bonds, methylenes, vinylidenes, acetylides, alkenes, alkynes, carbenes, carbynes, alkylidenes, alkylidynes, and others with various monometal, dimetal, and cluster metal species. Supporting ligands include -aryls, alkoxides, oxides, and phosphines. We are expanding our studies of both early and late transition metal species and electron-rich and electron-poor environments in order to more completely understand the electronic factors that serve to stabilize particular organic fragments and intermediates on metals. Additional new directions for this program are being taken in ultra-high vacuum surface UPS, XPS, scanning tunneling microscopy (STM) and atomic force microscopy (AFM) experiments on both physisorbed and chemisorbed organometallic thin films. The combination of these methods provides additional electronic structure information on surface-molecule and molecule-molecule interactions. A very important general result emerging from this program is the identification of a close relationship between the ionization energies of the species and the thermodynamics of the chemical and catalytic reactions of these systems.

  11. Plasma Enhanced Chemical Vapor Deposition Nanocrystalline Tungsten Carbide Thin Film and Its Electro-catalytic Activity

    Huajun ZHENG; Chunan MA; Jianguo HUANG; Guohua LI

    2005-01-01

    Nanocrystalline tungsten carbide thin films were fabricated on graphite substrates by plasma enhanced chemical vapor deposition (PECVD) at H2 and Ar atmosphere, using WF6 and CH4 as precursors. The crystal phase, structure and chemical components of the films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive spectrometer (EDS), respectively. The results show that the film prepared at CH4/WF6concentration ratio of 20 and at 800℃ is composed of spherical particles with a diameter of 20~35 nm. Electrochemical investigations show that the electrochemical real surface area of electrode of the film is large, and the electrode of the film exhibits higher electro-catalytic activity in the reaction of methanol oxidation. The designated constant current of the film catalyst is 123.6 mA/cm2 in the mixture solution of H2SO4 and CH3OH at the concentration of 0.5 and 2.0 mol/L at 70℃, and the designated constant potential is only 0.306 V (vs SCE).

  12. Chemically and biologically synthesized CPP-modified gelonin for enhanced anti-tumor activity.

    Shin, Meong Cheol; Zhang, Jian; David, Allan E; Trommer, Wolfgang E; Kwon, Young Min; Min, Kyoung Ah; Kim, Jin H; Yang, Victor C

    2013-11-28

    The ineffectiveness of small molecule drugs against cancer has generated significant interest in more potent macromolecular agents. Gelonin, a plant-derived toxin that inhibits protein translation, has attracted much attention in this regard. Due to its inability to internalize into cells, however, gelonin exerts only limited tumoricidal effect. To overcome this cell membrane barrier, we modified gelonin, via both chemical conjugation and genetic recombination methods, with low molecular weight protamine (LMWP), a cell-penetrating peptide (CPP) which was shown to efficiently ferry various cargoes into cells. Results confirmed that gelonin-LMWP chemical conjugate (cG-L) and recombinant gelonin-LMWP chimera (rG-L) possessed N-glycosidase activity equivalent to that of unmodified recombinant gelonin (rGel); however, unlike rGel, both gelonin-LMWPs were able to internalize into cells. Cytotoxicity studies further demonstrated that cG-L and rG-L exhibited significantly improved tumoricidal effects, with IC50 values being 120-fold lower than that of rGel. Moreover, when tested against a CT26 s.c. xenograft tumor mouse model, significant inhibition of tumor growth was observed with rG-L doses as low as 2 μg/tumor, while no detectable therapeutic effects were seen with rGel at 10-fold higher doses. Overall, this study demonstrated the potential of utilizing CPP-modified gelonin as a highly potent anticancer drug to overcome limitations of current chemotherapeutic agents. PMID:23973813

  13. Synthesis of CuS nanoparticles by a wet chemical route and their photocatalytic activity

    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, N2 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− 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.

  14. Neutron activation analysis applied to the chemical composition of metallic materials

    The physical properties of metallic materials, such as mechanical properties, corrosion resistance and others are determined by their chemical composition, which influences the various steps of the production process and the economic value attained by the materials. Instrumental neutron activation analysis was used in this work to evaluate the chemical composition of iron, steel, silicon and ferrosilicon reference materials. The concentration of the elements As, Co, Cr, Mn, Mo, Ni, V and W were analyzed in the iron and steel samples whereas As, Br, Co, Cr, K, Eu, Fe, La, Mn, Mo, Na, Nd, U, Th, Sb, Sc, Sm, Tb, V, W and Yb were determined in silicon and ferrosilicon samples. Accuracy was assessed comparing obtained results to reference materials certified values. Results of about 10 % were achieved for most of the elements. Precision was assessed by replicate measurements, and the results of about 10 % were also achieved. Accuracy and precision results showed that the technique is suitable for the metallic materials composition analysis. Interferences of Cr and Mn in V, Fe and Co in Mn; Co in Fe and Cr in Ti were quantified and only the last one was critical to the analysis of the materials employed in this work. (author)

  15. CHEMICAL ACTIVATION OF MOLECULES BY METALS: EXPERIMENTAL STUDIES OF ELECTRON DISTRIBUTIONS AND BONDING; FINAL

    This research program is directed at obtaining detailed experimental information on the electronic interactions between metals and organic molecules. These interactions provide low energy pathways for many important chemical and catalytic processes. A major feature of the program is the continued development and application of our special high-resolution valence photoelectron spectroscopy (UPS), and high-precision X-ray core photoelectron spectroscopy (XPS) instrumentation for study of organometallic molecules in the gas phase. The study involves a systematic approach towards understanding the interactions and activation of bound carbonyls, C-H bonds, methylenes, vinylidenes, acetylides, alkenes, alkynes, carbenes, carbynes, alkylidenes, alkylidynes, and others with various monometal, dimetal, and cluster metal species. Supporting ligands include -aryls, alkoxides, oxides, and phosphines. We are expanding our studies of both early and late transition metal species and electron-rich and electron-poor environments in order to more completely understand the electronic factors that serve to stabilize particular organic fragments and intermediates on metals. Additional new directions for this program are being taken in ultra-high vacuum surface UPS, XPS, scanning tunneling microscopy (STM) and atomic force microscopy (AFM) experiments on both physisorbed and chemisorbed organometallic thin films. The combination of these methods provides additional electronic structure information on surface-molecule and molecule-molecule interactions. A very important general result emerging from this program is the identification of a close relationship between the ionization energies of the species and the thermodynamics of the chemical and catalytic reactions of these systems

  16. Chemical analysis and antihyperglycemic activity of an original extract from burdock root (Arctium lappa).

    Tousch, Didier; Bidel, Luc P R; Cazals, Guillaume; Ferrare, Karine; Leroy, Jeremy; Faucanié, Marie; Chevassus, Hugues; Tournier, Michel; Lajoix, Anne-Dominique; Azay-Milhau, Jacqueline

    2014-08-01

    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. PMID:24933284

  17. Synthesis of CuS nanoparticles by a wet chemical route and their photocatalytic activity

    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.

  18. Endocrine-Disrupting Activity of Hydraulic Fracturing Chemicals and Adverse Health Outcomes After Prenatal Exposure in Male Mice.

    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

    2015-12-01

    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. PMID:26465197

  19. Preparation of highly porous carbonaceous sorbents from sewage sludge by physical and chemical activation

    Ros, A.; Martin, M.J. [Girona Univ., Lab. d' Enginyerie Quimica i Ambiental, Dept. d' Enginyeria Quimica, Agraria i Tecnologia Agroalimentaria, Facultat de Ciencies (Spain); Lillo-Rodenas, M.A.; Linares-Solano, A. [Alicante Univ., Dept. de Quimica Inorganica (Spain); Fuente, E.; Montes-Moran, M.A. [Instituto Nacional del Carbon, CSIC, Oviedo (Spain)

    2005-07-01

    Among the different porous materials, activated carbon (AC) is the most widely used for environmental applications such as gas-phase pollutant removal, gas separation, solvent recovery and water purification, because of its high specific surfacea. Commercial activated carbons are generally produced from coals and lignocellulosic materials [1]. Additionally, in the latest years great attention is being focused on the reuse of wastes such as sewage sludges [2,3]. The objective of this study is to find more effective activating procedures to prepare AC from sewage sludge. Both dried sludges from two different WWTP (SL, SB) and their corresponding chars prepared by pyrolysis (SL-P, SB-P) were activated using physical activation (CO{sub 2}) and chemical activation (H{sub 3}PO{sub 4}, NaOH and KOH). As shown in Table 1, pyrolysis of the raw sludges slightly increased the specific surface area, up to 50 m{sup 2}/g. Acid-washing of the pyrolyzed samples with 5 M HCl removes part of the metal content leading to an increase in the specific surface areas for both SL-PD and SB-PD, with surface areas of 428 m{sup 2}/g and 188 m{sup 2}/g, respectively. This simple washing treatment is useful for the development of porous adsorbents, especially in the case of SL derived materials. Our results show that CO{sub 2} physical activation of the pyrolyzed and the HCl-washed samples develops no appreciable porosity in the final materials, under the experimental conditions used. For CO{sub 2} activation, maximum temperatures of 870 C and holding times up to 4 hours in CO{sub 2} (100 ml/min) were used. Chemical activation with H{sub 3}PO{sub 4} of the pristine samples and those pyrolyzed was performed at 450 C, a temperature typically used for the activation by H{sub 3}PO{sub 4} of lignocellulosic precursors, and using two different H{sub 3}PO{sub 4} solutions (30 and 50% wt). These conditions were not either suitable for an efficient porosity development. A detailed study about the

  20. Chemical composition and antibacterial activity of the essential oil of Ambrosia peruviana Willd. from Venezuelan plains

    Carlos A. Yánez C.

    2011-08-01

    Full Text Available In Venezuela, are currently exploring new sources of natural antibacterial agents, due to increased bacterial resistance, including essential oils derived from plants. For this reason in the present study we determined the chemical composition of essential oil obtained from leaves collected on Ambrosia peruviana Willd Guasdualito, Apure State, Venezuela. The volatile compounds were isolated by hydrodistillation in a Clevenger trap and then subjected to qualitative analysis and quantitative by gas chromatography-mass spectrometry (GC / MS on an HP GC-MS System, model 5973, finding as the major compound gamma-curcumeno (23.99% followed by curcumeno-ar (14.08%, bornyl acetate (10.35%, camphor (5.03% and epoxide oximene (4.79%. The antibacterial activity of essential oil by the agar diffusion method with discs against Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Klebsiella pneumoniae, Salmonella typhi and Pseudomonas aeruginosa showed activity against S. aureus, E. faecalis, E. coli and S. Typhi, with MIC values of 350-500 micrograms/ mL. This research represents the first report of antibacterial activity of A. peruviana.

  1. Chemical constituents from the leaves of Boehmeria rugulosa with antidiabetic and antimicrobial activities.

    Semwal, Deepak Kumar; Rawat, Usha; Semwal, Ravindra; Singh, Randhir; Krishan, Pawan; Singh, Manjeet; Singh, Gur Jas Preet

    2009-12-01

    Three new flavonoid glycosides, named chalcone-6'-hydroxy-2',3,4-trimethoxy-4'-O-beta-D-glucopyranoside (1), isoflavone-3',4',5,6-tetrahydroxy-7-O-[beta-D-glucopyranosyl-(1-->3)-alpha-L-rhamnopyranoside] (2), and isoflavone-3',4',5,6-tetrahydroxy-7-O-[beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl-(1-->3)-alpha-L-rhamnopyranoside] (3), were isolated from the leaves of Boehmeria rugulosa, together with five known compounds, beta-sitosterol, quercetin, 3,4-dimethoxy-omega-(2'-piperidyl)-acetophenone (4), boehmeriasin A (5), and quercetin-7-O-beta-D-glucopyranoside. The structures of the isolated compounds were determined by means of chemical and spectral data including 2D NMR experiments. The ethanolic extract of leaves showed significant hypoglycemic activity on alloxan-induced diabetic mice. Glibenclamide, an oral hypoglycemic agent (5 mg/kg, p.o.), was used as a positive control. The ethanolic extract of the plant as well as the isolated compounds 1-3 (25 microg/ml) showed potent antimicrobial activity against two bacterial species (Staphylococcus aureus and Streptococcus mutans) and three fungus pathogens (Microsporum gypseum, Microsporum canis, and Trichophyton rubrum). The activities of the isolated compounds 1-3 have been compared with positive controls, novobiocin, and erythromycin (15 microg/ml). PMID:20183275

  2. Anti-Candida activity and chemical composition of Cinnamomum zeylanicum blume essential oil

    Ricardo Dias de Castro

    2013-10-01

    Full Text Available The purpose of this study was to identify the anti-Candida activity and chemical composition of the essential oil (EO of Cinnamomum zeylanicum (cinnamon. For this, tests were conducted to determine the Minimum Inhibitory Concentration (MIC and Minimum Fungicidal Concentration (MFC and the action of C. zeylanicum EO on fungal cell wall of Candida albicans, C. tropicalis and C. krusei strains. The composition of the was analysed by gas chromatography with mass spectrometry. Significant antifungal activity of the EO was observed on the strains tested, with 87.5% and 62.5% of them sensitive, respectively at a MIC of 312.5 µg/mL and MFC of 2500 µg/mL. In the presence of sorbitol, the MIC was 625 µg/mL against all the strains, showing a possible action of the EO on fungal cell wall. Eugenol (73.27% and trans-β-caryophyllene (5.38% were found in higher concentrations. The results indicated anti-Candida activity of the EO analyzed and suggested that it occurred due to the action on fungal cell wall.

  3. Differences in the chemical profiles and biological activities of Paeonia lactiflora and Paeonia obovata.

    Bae, Ji-Yeong; Kim, Chul Young; Kim, Hyun Jin; Park, Jong Hee; Ahn, Mi-Jeong

    2015-02-01

    Paeonia lactiflora and P. obovata are perennial herbs, each root of which has been consumed as a major oriental medicine, Paeoniae Radix and a famous folk medicine, Mountain Paeony Root, respectively. Although morphological studies have been performed comparing these two plants, there is insufficient scientific evidence that characterizes the differences in their chemical profiles and biological activities. Hence, the present study was undertaken to compare these two medicinal foods using a high-performance liquid chromatography-diode-array detector (HPLC-DAD) analysis and a gastric ulcer model in mice. HPLC analysis employed to assess the nine components revealed that P. lactiflora exhibited higher contents of phenolic compounds than P. obovata. Although a monoterpene glycoside, 6'-O-acetylpaeoniflorin was identified in P. obovata, it was not detected in P. lactiflora. Multivariate statistical analysis for HPLC data revealed that the orthogonal projections to latent structure-discriminant analysis is more appropriate than principal component analysis for differentiating the two groups. Moreover, the 50% methanol P. lactiflora extract (PL) was more effective against experimental gastric ulcer than P. obovata extract (PO) in the HCl/ethanol-induced ulcer model. In addition, PL displayed higher 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and lower nitric oxide production in a murine macrophage cell line, RAW 264.7, than PO. The DPPH radical scavenging activity of PL was as high as that of the positive control, butylated hydroxytoluene, at a concentration of 25 μg/mL. PMID:25299493

  4. Antibacterial activity and chemical compounds of leaves and branches of Protium hebetatum

    G.G. CONRADO

    2015-01-01

    Full Text Available ABSTRACT The extracts and fractions of leaves and branches of Protium hebetatum D. C. Daly (Burseraceae were investigated for their antibacterial activity and chemical composition. The methanol extract of branches (EMG was considered active against the Escherichia coli and the Proteus vulgaris, showing an inhibition zone of 13 mm, and was selected for bioassay-guided phytochemical fractionation. From the technique of broth microdilution, the extract was considered a moderate inhibitor against Staphylococcus aureus, Pseudomonas aeruginosa and Enterococcus faecalis, with a minimum inhibitory concentration (MIC of 1 mg/mL. The dichloromethane fraction was considered a moderate inhibitor against S. aureus (MIC of 1 mg/mL and a potent inhibitor against E. faecalis (MIC of 0.5 mg/mL. F1, F2, F5 and F6 from chromatographic column of dichloromethane fraction were considered moderate inhibitors against S. aureus (MIC of 1 mg/mL. Through analysis by a gas chromatography mass spectrometry, eighteen compounds were identified, from which thirteen (isoeugenol, p-vinylguaiacol, metoxyeugenol, coumarin, 5-hydroxy-scopoletin, 4,7-dihydroxy-6-metoxicromam-2-one, 4[(1E]-3-hydroxy-1-propenyl-2-methoxyphenol, piperonal, scoparon, o-guaiacol, spathulenol, seringol and antiarol are unprecedented in these species. We also identified the triterpenes α-amyrin and β-amyrin, the steroids stigmasterol and sitosterol and the coumarin scopoletin, which was closely linked to the antibacterial activity of the samples.

  5. Chemical Composition and Biological Activities of Essential Oils of Eremanthus erythropappus (DC McLeisch (Asteraceae

    Orlando V. Sousa

    2013-08-01

    Full Text Available The chemical composition of the essential oils obtained by hydrodistillation of different parts of Eremanthus erythropappus, including leaves, branches and inflorescences, was investigated by Gas Chromatography and Gas Chromatography/Mass Spectrometry. The antimicrobial activity of the oils was assessed by the disc diffusion and microdilution methods, while the antioxidant activity was evaluated by DPPH and reducing power tests. The main compounds found in the essential oils derived from the inflorescences and leaves were β-caryophyllene, germacrene-D, α-copaene and β-pinene. α-Bisabolol was the major component in the branches. The oils were active against Staphylococcus aureus, Streptococcus pyogenes and fungi, but not Escherichia coli and Pseudomonas aeruginosa. The MIC values ranged from 0.01 to 0.50 mg/mL. Using the DPPH test, the IC50 values ranged from 38.77 ± 0.76 to 102.24 ± 1.96 μg/mL, while the reducing power test produced IC50 values between 109.85 ± 1.68 and 169.53 ± 0.64 μg/mL. The results revealed that the E. erythropappus oils are new promising potential sources of antimicrobial and antioxidant compounds with good future practical applications for human health.

  6. Chemical composition of lateritic ores and its industrial processing products by neutron activation analysis

    Several techniques of neutron activation analysis for the determination of chemical composition of lateritic ores and in its industrial processing products has been assayed. Instrumental neutron activation analysis with thermal neutrons from reactor combined with short irradiations, allowed the determination of a group of elements, but it was practically not applicable with long irradiations due to the strongly interferences of Co-60, Cr-51, Sc-46 and Fe-59. Reactor epithermal neutron activation analysis (ENAA), significantly reduced such interferences and at least 20 elements had been determined by this technique. An improvement of practical detection limits (10-6%) had been achieved combining the ENAA with one step radiochemical separation by using either the ion exchange in samples of ores and tails or the cobalt liquid extraction in the elaborated products. Nearly 30 elements had been determined by this combination, that also gives a valuable information concerning the distribution of some ''dispersed'' (Se, Ir, Au, etc.) and rare earths elements (La, Sm, Yb, Lu, etc.) during the industrial treatment of lateritic ores in Cuba. 21 refs

  7. CHEMICALLY FABRICATED SILVER NANOPARTICLES ENHANCES THE ACTIVITY OF ANTIBIOTICS AGAINST SELECTED HUMAN BACTERIAL PATHOGENS

    S. Thangapandiyan and P. Prema*

    2012-05-01

    Full Text Available Due to the outbreak of infectious diseases caused by different pathogenic bacteria and the development of antibiotic resistance, the pharmaceutical companies and the researchers are now searching for new unconventional antibacterial agents. Nanotechnology represents a modern and innovative approach to develop new formulations based on metallic nanoparticles with antimicrobial properties. The potential bioactivity of chemically fabricated silver nanoparticles has been extensively studied. However, the antibacterial activity of silver nanoparticles individually or in combination with different antibiotics has not been demonstrated. In the present investigations, the effect of silver nanoparticles on the antibacterial activity of different antibiotics was evaluated against selected human bacterial pathogens such as Staphylococcus aureus, Streptococcus epidermis, Escherichia coli, Pseudomonas aeruginosa, and Bacillus cereus by disc diffusion method. In the presence of sub - inhibitory concentration of silver nanoparticles (100µL/disc, the antibacterial activities of all antibiotics are increased from 1 mm to 10 mm. The maximum fold increase was noticed for vancomycin against Pseudomonas aeruginosa (66.67%, Escherichia coli (62.50%, and Staphylococcus aureus (46% followed by rifampicin against Bacillus cereus (66.67% and kanamycin against Streptococcus epidermis (25%. These results signify that the silver nanoparticles showed potential antibacterial action of ß-lactams, glycopeptides, aminoglycosides, sulphonamides suggesting a possible utilization of silver nanocompounds in combination therapy against selected pathogens used in the experiment.

  8. Chemical sensor platform for non-invasive monitoring of activity and dehydration.

    Solovei, Dmitry; Žák, Jaromír; Majzlíková, Petra; Sedláček, Jiří; Hubálek, Jaromír

    2015-01-01

    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. PMID:25594591

  9. Antibiotic pigment from desert soil actinomycetes; biological activity, purification and chemical screening

    Selvameenal L

    2009-01-01

    Full Text Available An actinomycete strain, Streptomyces hygroscopicus subsp. ossamyceticus (strain D10 was isolated from Thar Desert soil, Rajasthan during the year 2006 and found to produce a yellow color pigment with antibiotic activity. Crude pigment was produced from strain D10 by solid state fermentation using wheat bran medium followed by extraction with ethyl acetate. The antimicrobial activity of the crude pigment was evaluated against drug resistant pathogens such as methicillin-resistant Staphylococcus aureus, vancomycin-resistant Staphylococcus aureus, extended spectrum b-lactamase producing cultures of Escherichia coli, Pseudomonas aeruginosa and Klebsiella sp. About 420 mg of crude pigment was produced per 10 g of wheat bran medium. In the disc diffusion method the crude ethyl acetate extract showed a minimum of 10 mm inhibition against Klebsiella sp. and maximum of 19 mm of inhibition against Escherichia coli. The crude pigment was partially purified using thin layer chromatography with the solvent system chloroform:methanol (30:70 and the Rf value was calculated as 0.768. Antimicrobial activity of the partially purified compound from thin layer chromatography was determined using the bioautography method. The purified pigment showed minimum of 15 mm inhibition against Klebsiella sp. and a maximum of 23 mm of inhibition against vancomycin-resistant Staphylococcus aureus in the disc diffusion method. Based on the results of chemical screening, the pigment was tentatively identified as group of sugar containing molecules.

  10. Chemical Composition, Herbicidal and Antifungal Activity of Satureja cuneifolia Essential Oils from Spain.

    García-Rellán, David; Verdeguer, Mercedes; Salamone, Adele; Blázquez, María Amparo; Boira, Herminio

    2016-06-01

    The chemical composition of essential oils from Satureja cuneifolia growing in east Spain was analyzed by GC, GC/MS. Forty-five compounds accounting for 99.1% of the total oil were identified. Camphor (47.6%), followed by camphene (13.6%) were the main compounds. Their herbicidal and antifungal activity was tested in vitro against three weeds (Amaranthus hybridus, Portulaca oleracea and Conyza canadensis) and eleven common pathogenic or saprophytic fungi (Phytophthora citrophthora, P. palmivora, Pythium litorale, Verticillium dahlia, Rhizoctonia solani, Penicillium hirsutum, Colletotrichum gloeosporioides, Phaeoacremonium aleophilum, Phaemoniella chlamydospora, Cylindrocarpon liriodendri and C. macrodidymum). The essential oil was very active against A. hybridus and C. canadensis significantly inhibiting their germination and seedling growth. Minor activity was shown against P. oleracea, depending on the concentration applied. P. palmivora, P. citrophthora and Pa. chlamydospora were the most sensitive fungi to the treatment with the essential oil, whereas R. solani showed no inhibition. Results showed that S. cuneifolia essential oil could be used for biocontrol of weeds and fungal plant diseases. PMID:27534131

  11. Study on antibacterial activity of chemically synthesized PANI-Ag-Au nanocomposite

    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

  12. Chemical Composition, Antibacterial and Antioxidant Activities of Six Essentials Oils from the Alliaceae Family

    Dima Mnayer

    2014-12-01

    Full Text Available Six essential oils (EOs from the Alliaceae family, namely garlic (Allium sativum, onion (Allium cepa, leek (Allium porrum, Chinese chive (Allium tuberosum, shallot (Allium ascalonicum and chive (Allium schoenoprasum were characterized by GC and GC-MS and evaluated for their functional food properties. Antibacterial properties were tested on five food-borne pathogens: Two Gram-positive Staphylococcus aureus (ATCC 25923, Listeria monocytogenes (ATCC 19115 and three Gram-negative Salmonella Typhimurium (ATCC 14028, Escherichia coli (ATCC 8739 and Campylobacter jejuni (ATCC 33291 bacteria. Antioxidant and radical-scavenging properties were tested by means of Folin-Ciocalteu and 2,2-diphenyl-1-picrylhydrazyl (DPPH assays. Garlic, Chinese chive and onion EOs had the highest antibacterial activity whereas shallot and leek EOs were the strongest antioxidants. Heating caused a decrease in the antioxidant activity of these Eos, as shown in the Total Polar Materials (TPM test. Suggestions on relationships between chemical composition and biological activities are presented. Results show that the EOs could be of value in the food industry as alternatives to synthetic antioxidants.

  13. Chemical composition, antioxidant and antimicrobial activities of citrus jambhiri lush and citrus reticulata blanco essential oils

    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)

  14. Effect Of GAMMA Radiation On Antimicrobial Activity And Chemical Constituents Of Marjoram (Majorana Hortensis Essential Oil

    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.

  15. Chemical Sensor Platform for Non-Invasive Monitoring of Activity and Dehydration

    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.

  16. Chemical composition and antioxidant activity of jatobá-do-cerrado (Hymenaea stigonocarpa Mart. flour

    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.

  17. Study on antibacterial activity of chemically synthesized PANI-Ag-Au nanocomposite

    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.

  18. TREATMENT OF RADIOACTIVE WASTE SOLUTIONS CONTAINING CESIUM AND STRONTIUM BY CHEMICALLY MODIFIED ACTIVATED CARBON

    The aim of this study is to develop activated carbon prepared from peach stone shell as an adsorbent for Cs+ and Sr2+ ions from their aqueous waste solutions. In this respect, five samples of peach stone shell were investigated. The first four samples were prepared by immersing the samples in different concentrations of either ZnCl2 or KOH, individually, prior to heat treatment at 500oC. The fifth sample was prepared only by thermal treatment at 500oC.The physical and chemical characteristics of the prepared samples were carried out. A comparative study for the removal of Cs+ and Sr2+ ions from their aqueous waste solutions using the investigated samples have been carried out using batch experiments.The different parameters affecting adsorption process such as contact time and metal ion concentration were studied. The results obtained showed that the activated carbon prepared using ZnCl2 was more effective than the other investigated samples for adsorbing Cs+ and Sr2+ ions since the removal percentages reached 85% and 98% , respectively, while the activated carbon prepared using KOH was less effective for the removal of the same elements since the removal percentages reached 69% and 60%, respectively. In case of using physically activated carbon, the removal percentages reached 18% and 25% for Cs+ and Sr2+, respectively.From the obtained data, it can be concluded that the activated carbon prepared using ZnCl2 can be used as a good adsorbent for the removal of the investigated elements that may present in radioactive waste solutions before their discharge to the environment

  19. Anti-inflammatory activity and chemical composition of the essential oils from Senecio flammeus.

    Xiao, Kai-Jun; Wang, Wen-Xia; Dai, Jia-Li; Zhu, Liang

    2014-01-01

    Many species from Senecio genus have been used in traditional medicine, and their pharmacological activities have been demonstrated. This study investigated the chemical composition and anti-inflammatory activities of essential oils from Senecio flammeus. A total of 48 components representing 98.41 % of the total oils were identified. The main compounds in the oils were α-farnesene (11.26 %), caryophyllene (8.69 %), n-hexadecanoic acid (7.23 %), and α-pinene (6.36 %). The anti-inflammatory activity of the essential oils was evaluated in rodents (10-90 mg/kg bw) in classical models of inflammation [carrageenan-induced paw edema, 12-O-tetradecanoyl-phorbol-13-acetate (TPA)-induced ear edema, and cotton pellet-induced granuloma]. The essential oils at doses of 10, 30, and 90 mg/kg bw significantly reduced carrageenan-induced paw edema by 17.42 % (P < 0.05), 52.90 % (P < 0.05), and 66.45 % (P < 0.05) 4 h after carrageenan injection, respectively, and significantly reduced myeloperoxidase activity (P < 0.05). The essential oils (10, 30, and 90 mg/kg) also produced a significant dose-dependent response to reduce TPA-induced ear edema by 20.27 % (P < 0.05), 33.06 % (P < 0.05), and 53.90 % (P < 0.05), respectively. The essential oils produced significant dose-response anti-inflammatory activity against cotton pellet-induced granuloma that peaked at the highest dose of 90 mg/kg (49.08 % wet weight and 47.29 % dry weight). Results demonstrate that the essential oils of S. flammeus were effective in the treatment of both acute and chronic inflammatory conditions, thereby supporting the traditional use of this herb. PMID:26417301

  20. Chemical Composition, Antioxidant and Cytotoxic Activities of Roots and Fruits of Berberis libanotica.

    El Hosry, Leina; Boyer, Laurent; Garayev, Elnur E; Mabrouki, Fathi; Bun, Sok-Siya; Debrauwer, Laurent; Auezova, Lizette; Cheble, Edmond; Elias, Riad

    2016-05-01

    Fourteen compounds belonging to different chemical classes were characterized in the roots and fruits extracts from Berberis libanotica, using the same HPLC-DAD-MS method. Thirteen were reported, for the first time, from the fruits whereas the roots contained mostly alkaloids of which 3 out of 5 are reported for the first time. Their structures were established on the basis of MS data as gallic acid (1), chlorogenic acid (2), delphinidin (3), oxyacanthine (4), rutin (5), hyperoside (6), berbamine (7), isoquercitrin (8), quercitrin (9), jatrorrhizine (10), palmatine (11), berberine (12), quercetin (13) and luteolin (14). Extracts containing compounds 4 and 7 showed significant cytotoxicity against the HT29 cell line with an IC50 of 12.2-26.1 μg/mL. Fruits extracts, due mostly to compounds 1 and 2, showed potent antioxidant activities with an EC50 of 0.0025-0.019 mg/mL. PMID:27319140

  1. New possibilities of chemical concentration in activation analysis of some noble and rare metals

    The possibility of concentrating Pt, Ir, Au, Ag, Re and some other elements from samples of chromites, sulfide ores, laterites, shales, titanium magnetites, and ultrabasic rocks was studied. A new simple procedure is based on sublimation of elements to be determined in air stream at 1200 deg C in the presence of some powdered reagents (e.g., TiO2, Nb2O5, Nb) to enhance the yield, and on the use of chemical filters (CaO, MgO, TiO2, Al2O3, Nb2O5) absorbing the interfering volatile elements from the gas phase. Methods of neutron activation and X-ray fluorescence isotopic excitation were used to analyze the obtained concentrates

  2. A chemical activity evaluation of two dental calcium silicate-based materials

    Chalas Renata

    2015-06-01

    Full Text Available Calcium silicate-based materials are interesting products widely used in dentistry. The study was designed to compare the chemical reaction between analyzed two preparates and dentin during cavity lining. In our work, dentinal discs were prepared from human extracted teeth filled with Biodentine and MTA+. The samples were then analyzed by way of SEM, EDS and Raman spectroscopy. The obtained results revealed differences in elemental composition between both materials. Biodentine showed higher activity in contact with dentine. Moreover, the interfacial layer in the tooth filled by Biodentine was wider than that in the tooth filled with MTA+. The applied methods of analysis confirmed that both materials have a bioactive potential which is a promising ability.

  3. Efficiency of generation of chemically active species by pulsed corona discharges

    G-values for the production of chemically active species by pulsed corona discharges are estimated within the framework of analytical streamer theory. Estimates for the production of oxygen and nitrogen atoms in the heads of propagating streamers are compared with recent experimental results obtained with the use of very short current pulses of duration of several nanoseconds. Production of oxygen and nitrogen atoms for long current pulses, of duration of several hundred nanoseconds, at a stage after bridging the discharge gap by a streamer is also considered. It is shown that, while oxygen atoms are produced during the discharge, generation of nitrogen atoms takes place mainly after the discharge, in collisions between vibrationally excited nitrogen molecules. (fast track communication)

  4. Chemical constituents and biological activities of species of Justicia: a review

    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.

  5. Chemical Composition and in vitro Antioxidant Activity of Mutellina purpurea Thell. Flowers Essential Oil

    Elwira Sieniawska

    2014-03-01

    Full Text Available Mutellina purpurea L. belongs to Apiaceae family and is known as Alpin lovage considered as a forage for animals nutrition because of the presence of sufficient concentration of minerals like calcium and potassium. The chemical composition of the essential oil obtained by hydrodistillation in a Clevenger apparatus and aroma of inflorescences of Mutellina purpurea (Poir. Thell. was analyzed by GC/MS and GC-FID. Sabinene (19.2%, a -pinene (12,6%, (E-sesquisabinene hydrate (9.0%, myrcene (7.8%, (Z-sesquisabinene hydrate (7.5% and a -bisabolol (6.7% dominated in the essential oil obtained by hydrodistillation. S tatic headspace technique gave sabinene (23.0%, p-cresol (17.4%, a - pinene (17.0% and myrcene (10.9% as a major constituents. Antioxidant activity of the oil was evaluated by ABTS assay.

  6. Assessment of some chemical element contents in Traganum nudatum Del shrub using instrumental neutron activation analysis

    Bouzid Nedjimi; Brahim Beladel

    2015-01-01

    Instrumental neutron activation analysis (INAA) has been used to determine some chemical element contents (K, Ca, Na, Fe, Zn, Co, Eu, Sb, and Sc) in Traganum nudatum Del (Chenopodiaceae family) consumed in North African rangelands by sheep livestock. Samples were collected from the area of Djelfa in an arid steppe of Algeria. Results show that pasture halophyte had sufficient levels of K, Ca, Zn, and Co to meet the requirements of ruminants. However, it seems that this halophyte shrub had substantial amounts of Na, higher than the critical level established by the National Research Council (NRC). Eu, Sb, and Sc were within the safety baseline of all the assayed elements recommended by the NRC. The high Na content (∼10 g/kg) in this halophytic species requires elevated intake of water by livestock.

  7. Determination of chemical pollutants in the atmosphere of the Valley of Toluca by neutron activation analysis

    The studies about the presence of contaminants in the atmosphere of diverse cities have been increased widely because to the problems that those cause to public health. Because of this in 1986 was made an Atmospheric Monitoring Program in the Valley of Toluca including the city of Toluca and Toluca- Lerma industrial corridor. That program consist of a preliminary net of sampling for the recollection of total suspended particles on glass-fiber filters, the sampling was performed two times a week in five different zones. To date have been analyzed some of these filters by atomic absorption in the Chemistry School of the Mexico's State University. In this work, is showed the establishment of chemical treatment technique and the results of quantitative analysis through neutron activation in filters of recent monitoring. (Author)

  8. The geographical origin and chemical composition in phellinus mushrooms measured by instrumental neutron activation analysis

    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)

  9. Determination of rare earth elements in Taiwan monazite by chemical neutron activation analysis

    Taiwan monazite is a unique mineral obtained from the heavy sand found in the river floor of Tzuo-suei river and En-suei river. Both rivers are flowing parallel with separated narrow area into the sea at southwestern coast of Taiwan. The characteristic of monazite is that it contains considerable rare earth elements (REEs). REEs are considered very useful elements in the local industries and scientific researches such as ceramic, semiconductors, and glass optics. In this study, chemical neutron activation analysis (CNAA) was used to determine the contents of REEs in Taiwan monazite. A few milligram of monazite was digested in the microwave oven for 25 minutes with mixed acid (conc. HNO3 and HClO4). REEs were preconcentrated by hydrated magnesium oxide and CNAA was performed. (author)

  10. Partial chemical composition and antimicrobial activity of Daucus crinitus Desf. extracts

    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.

  11. Advanced Chemical Reduction of Reduced Graphene Oxide and Its Photocatalytic Activity in Degrading Reactive Black 5

    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.

  12. Supported gold catalysis: from small molecule activation to green chemical synthesis.

    Liu, Xiang; He, Lin; Liu, Yong-Mei; Cao, Yong

    2014-03-18

    With diminishing natural resources, there is an ever-increasing demand for cost-effective and sustainable production of fine and commodity chemicals. For this purpose, there is a need for new catalytic methods that can permit efficient and targeted conversion of fossil and biorenewable feedstocks with lower energy requirements and environmental impact. A significant number of industrial catalytic processes are performed by platinum-group-metal (PGM)-based heterogeneous catalysts capable of activating a range of important small molecules, such as CO, O2, H2, and N2. In contrast, there is a general feeling that gold (Au) cannot act as an efficient catalyst because of its inability to activate most molecules, which is essential to any catalytic processes. As a consequence, researchers have long neglected the potential for use of gold as a catalyst. In recent years, however, chemists have put forth tremendous effort and progress in the use of supported gold catalysts to facilitate a variety of useful synthetic transformations. The seminal discovery by Haruta in 1987 that suitably prepared Au-based catalysts were surprisingly active for CO oxidation even at 200 K initiated rapid development of the field. Since then, researchers have widely employed Au-based catalysts in many types of mild chemical processes, with special focus on selective reactions involving small molecules (for example, CO, H2O, O2, or H2) as a reactant. That gold in the form of tiny nanoparticles (NPs, generally less than 5 nm in diameter) can subtly activate the reactant molecules under mild conditions has been evoked to explain the superior effectiveness of gold compared with conventional PGMs. In this context, Au-based catalysts are gaining great significance in developing new green processes with improved selectivity and energy minimization. In this Account, we describe our efforts toward the development of a range of green and selective processes largely through the appropriate choice of Au

  13. Matching Element Symbols with State Abbreviations: A Fun Activity for Browsing the Periodic Table of Chemical Elements

    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…

  14. Insecticidal activities and chemical components of alcohol extract from leaves of Rhodendron dauricum L.

    SUN Mo-long; WANG Tian-miao

    2011-01-01

    The extract from leaves of Rhododendron dauricum L. was extracted with 95% alcohol by common method for studying its insecticidal activities. The chemical components of the alcohol extract and relative contents were analyzed by GC-MS. The insecticidal activities of the alcohol extract were tested on the 2nd-3rd instar larvae of Lymantria dispar L. for five days. Five concentrations of the extract samples were designed as 50, 10, 5, 1, and 0.5 g·L-1. The results show that the alcohol extracts from leaves of R. dauricum exhibited insecticidal activities against larvae of L. dispar. The corrected mortality of larvae of L. dispar for was over 50% for both contact toxicity and stomach toxicity at the extract concentration of ≥ 5 g·L-1 after five days of application. The insecticidal activity in contact toxicity is more effect than stomach toxicity for the alcohol extract. Twenty compounds, with total GC relative contents of 93.81% in the alcohol extract from leaves of R. dauricum were identified. The main chemical components in the cxtract are: (1) 4,5-Dihydro-5-oxo-3-(p-tolyl) isoxazole, with a relative content of 40.03%; (2) 1,3-Benzenediol, 5-methyl-2-(3,7,11-trimethyl-2,6,10-dodecatrienyl)-, (E,E)-, the relative content 18.27%; (3) 3,6-Diphenyl-1,2,3,4,5,6,7,8-octahydro-l,8-acridinedione, the relative content 3.89%;(4) 6H-[l ,2,4]Triazolo[1,5-a]indole, 4a,5,7,8,8a,9-hexahydro-9-methylene-, the relative content 2.99%; (5) 7-Amino-4-methyl-l,8-naphthyridino2-ol, the relative content 2.64%; (6) 4-Methyl-2,6-dihydroxyquinoline, the relative content 2.63%; (7) 2,4,6-Triaminoquilazoline, the relative content 2.27%; (8) 2(1H)-Quinolinone,4-hydroxy-1-methyl-, the relative content 2.02%.

  15. The active site of hen egg-white lysozyme: flexibility and chemical bonding

    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

  16. Screening of chemical composition, antimicrobial and antioxidant activities of Artemisia essential oils.

    Lopes-Lutz, Daíse; Alviano, Daniela S; Alviano, Celuta S; Kolodziejczyk, Paul P

    2008-05-01

    The chemical composition of essential oils isolated from aerial parts of seven wild sages from Western Canada -Artemisia absinthium L., Artemisia biennis Willd., Artemisia cana Pursh, Artemisia dracunculus L., Artemisia frigida Willd., Artemisia longifolia Nutt. and Artemisia ludoviciana Nutt., was investigated by GC-MS. A total of 110 components were identified accounting for 71.0-98.8% of the oil composition. High contents of 1,8-cineole (21.5-27.6%) and camphor (15.9-37.3%) were found in Artemisia cana, A. frigida, A. longifolia and A. ludoviciana oils. The oil of A. ludoviciana was also characterized by a high content of oxygenated sesquiterpenes with a 5-ethenyltetrahydro-5-methyl-2-furanyl moiety, of which davanone (11.5%) was the main component identified. A. absinthium oil was characterized by high amounts of myrcene (10.8%), trans-thujone (10.1%) and trans-sabinyl acetate (26.4%). A. biennis yielded an oil rich in (Z)-beta-ocimene (34.7%), (E)-beta-farnesene (40.0%) and the acetylenes (11.0%) (Z)- and (E)-en-yn-dicycloethers. A. dracunculus oil contained predominantly phenylpropanoids such as methyl chavicol (16.2%) and methyl eugenol (35.8%). Artemisia oils had inhibitory effects on the growth of bacteria (Escherichia coli, Staphylococcus aureus, and Staphylococcus epidermidis), yeasts (Candida albicans, Cryptococcus neoformans), dermatophytes (Trichophyton rubrum, Microsporum canis, and Microsporum gypseum), Fonsecaea pedrosoi and Aspergillus niger. A. biennis oil was the most active against dermatophytes, Cryptococcus neoformans, Fonsecaea pedrosoi and Aspergillus niger, and A. absinthium oil the most active against Staphylococcus strains. In addition, antioxidant (beta-carotene/linoleate model) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activities were determined, and weak activities were found for these oils. PMID:18417176

  17. Chemical Constituents from the Branches of Carpinus turczaninowii with Antioxidative Activities

    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.

  18. Physico-chemical characteristics and antioxidant activity of goji fruits jam and jelly during storage

    Daniela ISTRATI

    2013-12-01

    Full Text Available Since the 1990s, when the news about antioxidants and their benefits to health has begun to spread to the general public, statements about the benefits of antioxidants ranged from preventing colds to cancer treatment. Fruits and vegetables are excellent sources of antioxidants. Since the beginning of the 21st century, goji berries have become increasingly popular in Europe and North America and have been promoted in advertisements and in the media as an anti-aging remedy. Goji is a relatively new name given to Lycium Barbarum and Lycium chinense, two nearby species, with a long history of use as medicinal and food plants in East Asia, particularly in China. In the present paper are presented analysis results of Goji fruits and food products made from goji fruits (jam and jelly. Storage conditions are important factors for jams and jelly quality. The objective of this study was to monitor the physicochemical stability, antioxidant activity and sensorial profile of goji fruits jam and jelly. Special attention was paid to total phenolic and flavonoid content, antioxidant activity, total soluble solids, titratable acidity, pH and sensorial characteristics. Our results showed the antioxidant activity of the goji fruit, values which correlate well with the results obtained for total phenolic (351±7.25 mg GAE/100g and flavonoid content (53.06±1.23 mg QE/100g. The antioxidant activity of the goji fruits was maintained also in the finished products obtained in the present study jam (60.98 % and jelly (41.96 %. Both goji fruits jam and goji fruits jelly showed no significant variations of physico-chemical characteristics and sensorial parameter scores after storage at refrigeration temperature for 10 days.

  19. Chemical Composition, Antioxidant, and Antibacterial Activities of Essential Oils from Etlingera brevilabrum Valeton

    Behnam Mahdavi

    2015-08-01

    Full Text Available Essential oils from fresh parts of Etlingera brevilabrum Valeton (Zingiberaceae including rhizome, stolon, stem, and leaves were hydrodistilled, and studied for their chemical composition, antioxidant, and antibacterial activity. Characterization by GC-FID and GC-MS showed monoterpene hydrocarbons dominated the oils of the leaves and stems (57.3 and 73.4% with oxygenated monoterpenes were dominant in the stolon and rhizomes (40.4 and 53.6%. The major compounds of the rhizome oil were perilla aldehyde (19.6% and bornyl acetate (17.6%; the stolon oil, β-pinene (30.6% and p-cymen-7-ol (25.0%; the stem oil, δ-3-carene (43.2% and α-thujene (17.7%; and the leaf oil, α-thujene (38.1% and p-cymen-7-ol (8.0%. The rhizome oil showed the highest antioxidant effects with IC 50 = 1236.54±12.83 µ g/mL in the DPPH radical scavenging activity, 22.76% inhibition in the β-carotene bleaching test at 1000 µ g/mL, and IC 50 = 878±16.54 µ g/mL in the ferrous ion chelating ability. Antibacterial activity demonstrated by disc diffusion assay showed that the rhizome, stem and leaf oils inhibited Staphylococcus aureus and MRSA but not Bacillus subtilis and Bacillus thuringiensis. For Gram negative bacteria, the rhizome oil prevented the growth of Proteus mirabilis ; the stem oil inhibited Escherichia coli and Proteus vulgaris ; and the leaf oil was active against E. coli , P. vulgaris , and P. mirabilis .

  20. Chemical Composition and Antioxidant Activity in Different Tissues of Brassica Vegetables

    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.

  1. Chemical use

    US Fish and Wildlife Service, Department of the Interior — This is a summary of research and activities related to chemical use on Neal Smith National Wildlife Refuge between 1992 and 2009. The chemicals used on the Refuge...

  2. Chemical constituents and antimicrobial activity of the ethanol extracts obtained from the flower, leaf and stem of Salvia officinalis L.

    MIHAILO S. RISTIC; ANA S. VELICKOVIC; ANDRIJA A. SMELCEROVIC; DRAGAN T. VELICKOVIC; NOVICA V. RANDJELOVIC

    2003-01-01

    In this paper a comparison of the chemical composition and antimicrobial action of the ethanol extracts from the flower, leaf and stem of the herbal species Salvia officinalis L. (Lamiaceae), originating from the southeast region of Serbia was carried out. The chemical composition of the extracts was determined by GC-FID and GC-MS analyses. Manool has the highest level of all the components (9.011.1 %). Antimicrobial activity was determined by the diffusion and dilution method, whereby the la...

  3. Chemical Composition and Antimicrobial Activity of Leaf, Ripe and Unripe Peel of Bitter Orange (Citrus aurantium) Essential Oils

    Fatemeh Azhdarzadeh; Mohammad Hojjati

    2016-01-01

    Background and Objectives: The chemical composition and antimicrobial activity of bitter orange (Citrus aurantium) leaf, ripe and unripe peel essential oils, cultivated in southwest of Iran, were investigated. Materials and Methods: The analysis of chemical composition of hydro-distilled essential oils was carried out by GC-MS. The disc diffusion and broth micro-dilution were used to assay the antimicrobial effect of achieved essential oils. Results: According to the GC-MS analysis, 3...

  4. Chemical constituents and antioxidant activity of the essential oil from leaves of Annona vepretorum Mart. (Annonaceae

    Camila de Souza Araújo

    2015-01-01

    Full Text Available Background: Annona vepretorum (AV is a native tree from Caatinga biome (semiarid region of Brazil popularly known as “araticum” and “pinha da Caatinga.” Objective: 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. Materials and Methods: 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. Results: 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 a 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.

  5. Chemical Tools of Octopus maya during Crab Predation Are Also Active on Conspecifics.

    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 3kDa leading to a metabolic phase (>3kDa) and a neurotoxic fraction (maya conspecifics, partly paralyzing and sedating them; this suggests that 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. PMID:26895025

  6. Evaluation of Chemically Activated Zeolite for Immobilizing the UraniumWaste

    The experimental investigation on the chemically activated local mineralmaterial of zeolite using H2SO4 with its various concentration of 0, 5, 10and 15 % and heating them by a furnace at the temperature of 100 - 400 oCfor evaluating their effectiveness on the immobilization of uranium wastewith the concentration of 100 ppm. Experimentally, this investigation is thefirst step of local mineral material usage as an alternative material for thetreatment of liquid waste containing radioactive element especially uranium.This investigation was performed by passing uranium solution feed with theconcentration of 100 ppm , pH=4 through the glass column containing activatedzeolite with the grain size of -100/+200, -80/+100 and -60/+80 mesh. Theexperimental resulted by maintaining the feed flow rate of 2.5 ml/min., pH=4obtaining the process condition in which uranium fraction contained in thezeolite column is given by DFU = 70.Therefore, it could be concluded thatthe most effective activation was obtained with H2SO4 as an activationmaterial of the concentration = 5 %, for the zeolite grain size of -100/+200mesh and the saturating time gained for the zeolite grain size of -100/+200mesh = 3030 minutes. (author)

  7. Chemical Composition, Larvicidal and Cytotoxic Activities of the Essential Oils from two Bauhinia Species

    Leôncio M. de Sousa

    2015-10-01

    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, Antioxidant, and Antimicrobial Activities of Essential Oils of Endlicheria arenosa (Lauraceae) from the Amazon.

    da Silva, Joyce Kelly R; da Trindade, Rafaela C S; Maia, José Guilherme S; Setzer, William N

    2016-05-01

    The essential oils (EOs) of leaves and twigs of Endlicheria arenosa Chanderb. were obtained by hydrodistillation using a Clevenger-type apparatus and the chemical composition was determined by GC and GC-MS. In total, 47 constituents were identified and sesquiterpene hydrocarbons (77.6%) were the main compounds found in the leaf EO, such as bicyclogermacrene (42.2%), germacrene D (12.5%) and β-caryophyllene (10.1%). Limonene (33.2%), terpinen-4-ol (15.6%) and δ-cadinol (6.9%) were the predominant constituents in the EO of the twigs. Using the DPPH radical-scavenging method, the EO of the leaves showed the greater radical-scavenging activity (216.5 ± 11.6 mg Trolox equivalents (TE)/mL compared to the EO of the twigs (122.6 ± 6.8 mg TE/mL). Also, the EO of leaves displayed promising antimicrobial activity against Escherichia coli (MIC 19.5 μg x mL(-1)). The present study is the first report about evaluation of volatile oils for this species. PMID:27319154

  9. Indole Alkaloids of the Stigonematales (Cyanophyta: Chemical Diversity, Biosynthesis and Biological Activity

    Katherine Walton

    2016-04-01

    Full Text Available The cyanobacteria are well recognized as producers of a wide array of bioactive metabolites including toxins, and potential drug candidates. However, a limited number of taxa are generally considered with respect to both of these aspects. That said, the order Stigonematales, although largely overlooked in this regard, has become increasingly recognized as a source of bioactive metabolites relevant to both human and environmental health. In particular, the hapalindoles and related indole alkaloids (i.e., ambiguines, fischerindoles, welwitindolinones from the order, represent a diverse, and phylogenetically characteristic, class of secondary metabolites with biological activity suggestive of potential as both environmental toxins, and promising drug discovery leads. The present review gives an overview of the chemical diversity of biologically active metabolites from the Stigonematales—and particularly the so-called hapalindole-type alkaloids—including their biosynthetic origins, and their pharmacologically and toxicologically relevant bioactivities. Taken together, the current evidence suggests that these alkaloids, and the associated cyanobacterial taxa from the order, warrant future consideration as both potentially harmful (i.e., “toxic” algae, and as promising leads for drug discovery.

  10. Plasmon-mediated photocatalytic activity of wet-chemically prepared ZnO nanowire arrays.

    Dao, Thang Duy; Han, Gui; Arai, Nono; Nabatame, Toshihide; Wada, Yoshiki; Hoang, Chung Vu; Aono, Masakazu; Nagao, Tadaaki

    2015-03-21

    We report on measurements and simulations of the efficient sunlight-driven and visible-active photocatalysts composed of plasmonic metal nanoparticles and ZnO nanowire (NW) arrays fabricated via an all-wet-chemical route. Because of the coupling between the ZnO dielectric response and the excitation of the Ag or Au nanoparticles, efficient electronic excitation can be induced in the vicinity of the metal-ZnO interfaces because optically-excited plasmonic particles can not only concentrate the electromagnetic field at the ZnO/particle interface, but also act as efficient sources of plasmonic hot electrons to be injected into the conduction band of the ZnO catalyst. The catalytic activities of the fabricated ZnO NWs are examined by photodegradation of methylene blue and by photocurrent measurements in a photovoltaic configuration. Numerical electromagnetic simulations were used to understand the behavior of the light on the nanometer-scale to clarify the catalytic enhancement mechanisms in both the ultraviolet (UV) and visible (VIS) regions. In addition, simulation results indicated that a near-surface normal but slightly tilted ZnO NW array geometry would provide an increased optical path length and enhanced multiple scattering and absorption processes arising from the localized surface plasmon resonances of the nanoparticles. The results obtained here clarify the role of the plasmon resonance and provide us with useful knowledge for the development of metal-oxide nano-hybrid materials for solar energy conversion. PMID:25700130

  11. Chemical composition and antifungal activity of essential oil from Eucalyptus smithii against dermatophytes

    Edilene Bolutari Baptista

    2015-12-01

    Full Text Available ABSTRACT INTRODUCTION: In this study, we evaluated the chemical composition of a commercial sample of essential oil from Eucalyptus smithii R.T. Baker and its antifungal activity against Microsporum canis ATCC 32903, Microsporum gypseum ATCC 14683, Trichophyton mentagrophytes ATCC 9533, T. mentagrophytes ATCC 11480, T. mentagrophytes ATCC 11481, and Trichophyton rubrum CCT 5507. METHODS: Morphological changes in these fungi after treatment with the oil were determined by scanning electron microscopy (SEM. The antifungal activity of the oil was determined on the basis of minimum inhibitory concentration (MIC and minimum fungicidal concentration (MFC values. RESULTS: The compound 1,8-cineole was found to be the predominant component (72.2% of the essential oil. The MIC values of the oil ranged from 62.5μg·mL−1 to >1,000μg·mL−1, and the MFC values of the oil ranged from 125μg·mL−1 to >1,000μg·mL−1. SEM analysis showed physical damage and morphological alterations in the fungi exposed to this oil. CONCLUSIONS: We demonstrated the potential of Eucalyptus smithii essential oil as a natural therapeutic agent for the treatment of dermatophytosis.

  12. Identification of the active site histidine in Staphylococcus hyicus lipase using chemical modification and mass spectrometry.

    Boots, J W; van Dongen, W D; Verheij, H M; de Haas, G H; Haverkamp, J; Slotboom, A J

    1995-04-01

    Staphylococcus hyicus lipase is a serine hydrolase. In order to identify the active site histidine of S. hyicus lipase we have chemically modified S. hyicus lipase with 1-bromo-octan-2-one. The enzyme is rapidly inactivated by this inhibitor with a half-time of 578 s at pH 6.5 and 30 degrees C. Addition of the enzyme's cofactor calcium increases the inactivation rate approx. 2-fold. When n-hexadecylphosphocholine, a non-hydrolysable substrate analogue, is added the inactivation rate decreases about 3-fold, suggesting that a residue in the active site of S. hyicus lipase is involved in the inactivation reaction. Inactivation of S. hyicus lipase with 14C-labelled 1-bromo-octan-2-one shows that 1.4 moles of inhibitor per mole of lipase are incorporated. The results of an electrospray mass spectrometric study of the inactivated enzyme are consistent with this finding. In order to identify the modified residue, both the inactivated and the unmodified lipase were digested with cyanogen bromide followed by trypsin. The resulting peptides were analysed using HPLC and fast atom bombardment mass spectrometry. The results allow the modified residue to be assigned to the peptide Gly597-Lys612. Collision induced dissociation mass spectrometry allowed the modified residue to be identified as His-600. From these results we conclude that this residue forms part of the catalytic triad of S. hyicus lipase. PMID:7711054

  13. Redox and Chemical Activities of the Hemes in the Sulfur Oxidation Pathway Enzyme SoxAX*

    Bradley, Justin M.; Marritt, Sophie J.; Kihlken, Margaret A.; Haynes, Kate; Hemmings, Andrew M.; Berks, Ben C.; Cheesman, Myles R.; Butt, Julea N.

    2012-01-01

    SoxAX enzymes couple disulfide bond formation to the reduction of cytochrome c in the first step of the phylogenetically widespread Sox microbial sulfur oxidation pathway. Rhodovulum sulfidophilum SoxAX contains three hemes. An electrochemical cell compatible with magnetic circular dichroism at near infrared wavelengths has been developed to resolve redox and chemical properties of the SoxAX hemes. In combination with potentiometric titrations monitored by electronic absorbance and EPR, this method defines midpoint potentials (Em) at pH 7.0 of approximately +210, −340, and −400 mV for the His/Met, His/Cys−, and active site His/CysS−-ligated heme, respectively. Exposing SoxAX to S2O42−, a substrate analog with Em ∼−450 mV, but not Eu(II) complexed with diethylene triamine pentaacetic acid (Em ∼−1140 mV), allows cyanide to displace the cysteine persulfide (CysS−) ligand to the active site heme. This provides the first evidence for the dissociation of CysS− that has been proposed as a key event in SoxAX catalysis. PMID:23060437

  14. Programmable SERS active substrates for chemical and biosensing applications using amorphous/crystalline hybrid silicon nanomaterial

    Powell, Jeffery Alexander; Venkatakrishnan, Krishnan; Tan, Bo

    2016-01-01

    We present the creation of a unique nanostructured amorphous/crystalline hybrid silicon material that exhibits surface enhanced Raman scattering (SERS) activity. This nanomaterial is an interconnected network of amorphous/crystalline nanospheroids which form a nanoweb structure; to our knowledge this material has not been previously observed nor has it been applied for use as a SERS sensing material. This material is formed using a femtosecond synthesis technique which facilitates a laser plume ion condensation formation mechanism. By fine-tuning the laser plume temperature and ion interaction mechanisms within the plume, we are able to precisely program the relative proportion of crystalline Si to amorphous Si content in the nanospheroids as well as the size distribution of individual nanospheroids and the size of Raman hotspot nanogaps. With the use of Rhodamine 6G (R6G) and Crystal Violet (CV) chemical dyes, we have been able to observe a maximum enhancement factor of 5.38 × 106 and 3.72 × 106 respectively, for the hybrid nanomaterial compared to a bulk Si wafer substrate. With the creation of a silicon-based nanomaterial capable of SERS detection of analytes, this work demonstrates a redefinition of the role of nanostructured Si from an inactive to SERS active role in nano-Raman sensing applications.

  15. Chemical structure and antioxidant activity of a new exopolysaccharide produced from Micrococcus luteus

    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.

  16. Surface Cleaning or Activation?Control of Surface Condition Prior to Thermo-Chemical Heat Treatment

    Brigitte Haase; Juan Dong; Jens Heinlein

    2004-01-01

    Actual heat treatment processes must face increasing specifications with reference to process quality, safety and results in terms of reproducibility and repeatability. They can be met only if the parts' surface condition is controlled during manufacturing and, especially, prior to the treatment. An electrochemical method for the detection of a steel part's surface condition is presented, together with results, consequences, and mechanisms concerning surface pre-treatment before the thermochemical process. A steel surface's activity or passivity can be detected electrochemically, independently from the chemical background. The selected method was the recording of potential vs. time curves at small constant currents, using a miniaturized electrochemical cell, a (nearly) non-destructive electrolyte and a potentio-galvanostatic setup. The method enables to distinguish types of surface contamination which do not interfere with the thermochemical process, from passive layers which do and must be removed. Whereas some types of passive layers can be removed using conventional cleaning processes and agents, others are so stable that their effects can only be overcome by applying an additional activation pre-treatment, e.g. oxynitriding.

  17. Chemical composition and antimicrobial activity of the essential oils from four Ruta species growing in Algeria.

    Haddouchi, Farah; Chaouche, Tarik Mohammed; Zaouali, Yosr; Ksouri, Riadh; Attou, Amina; Benmansour, Abdelhafid

    2013-11-01

    Antimicrobial properties of plants essential oils have been investigated in order to suggest them as potential tools to overcome the microbial drug resistance and the increasing incidence of food borne diseases problems. The aim of this research is to study the antibacterial and antifungal effects of four traditional plants essential oils, Ruta angustifolia, Ruta chalepensis, Ruta graveolens and Ruta tuberculata, against standard bacterial and fungal strains. The chemical compounds of the oils were examined by GC/MS. Results revealed a powerful antifungal activity against filamentous fungi. Aspergillus fumigatus and Cladosporium herbarum are the most sensitive strains to these oils with MIC values less than 3.5 μg ml(-1) for certain oils, reaching 7.8 μg ml(-1) for other. GC/MS essay exhibited ketones as the most abundant constituent of these oils except for R. tuberculata essential oil which has a completely different composition, monoterpenes alcohols being the most abundant. These compositions explain their potential antifungal activity. PMID:23768355

  18. Study on antibacterial activity of chemically synthesized PANI-Ag-Au nanocomposite

    Boomi, Pandi; Prabu, Halliah Gurumallesh; Manisankar, Paramasivam; Ravikumar, Sundaram

    2014-05-01

    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.

  19. Chemical Composition and Biological Activities of the Essential Oils from Three Melaleuca Species Grown in Tunisia

    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.

  20. Effect of chemical composition of isomorphous metavanadates on their catalytic activity toward carbon combustion

    Metal vanadates of K, Rb, and Cs and their solid solutions were prepared by reaction between carbonates and vanadium(V) oxide, characterized by X-ray diffraction and tested as catalysts for carbon combustion. These vanadates are all orthorhombic but show different lattice parameters depending on the ionic radius of alkali metals. A complete solubility in the solid state was found to exist for the systems KVO3-RbVO3 and RbVO3-CsVO3, while only terminal solid solutions were found in the KVO3-CsVO3 system. The lattice parameters (mainly b0) of the orthorhombic cell increased with the increase of the ionic radius of the alkali metal. This increase was found to be closely linked to the substitution of a larger metal for a smaller one when a complete solubility occurs. The catalytic activity, investigated by temperature programmed oxidation (TPO) experiments, improves progressively along with the introduction of a more electropositive and larger alkaline metal in the vanadate crystal structure. The catalytic performance, however, does not seem to be dependent on the crystal structure because, due to polymorphic transformations, not all these vanadates keep the orthorhombic structure in the temperature range suitable for the catalytic carbon combustion (350--600 C). The catalytic activity of these vanadates towards carbon combustion thus seems to be strictly related to their chemical composition only

  1. CHEMICAL, PHYSICAL AND SENSORY ANALYSIS OF ACTIVITY DIFFERENT YEAST SPECIES ON IDENTICAL SUBSTRATE IN WINE PRODUCTION

    Vladimír Vietoris

    2013-02-01

    Full Text Available Rizling vlašský is the second most important variety in Slovakia. The science of wine production includes a summary of knowledge and experience in the field of grape growing and wine making, or the production of different types of wines using specific methods of production. Wine quality is the result of the interaction between yeast, bacteria and microscopic funguses. In this research, we studied the effects of active dry wine yeasts on chemical, physical and sensory parameters in wine production. We have applied five kinds of yeasts (FERMIVIN, FERMIVIN PDV, FERMICRU AR2, FERMIFLOR and FERMICRU VB1. It can be concluded that the application of active dry wine yeasts is beneficial for the production of rizling vlašský. The best showing were yeasts FERMIFLOR and FERMIVIN PDM. In the last sample where they were left the original yeasts the varietal aroma was preserved. It can be noted that the wine was right technologically produced and all wines were harmonious with a pleasant fresh taste.

  2. Stability, antimicrobial activity, and effect of nisin on the physico-chemical properties of fruit juices.

    de Oliveira Junior, Adelson Alves; de Araújo Couto, Hyrla Grazielle Silva; Barbosa, Ana Andréa Teixeira; Carnelossi, Marcelo Augusto Guitierrez; de Moura, Tatiana Rodrigues

    2015-10-15

    Heat processing is the most commonly used hurdle for inactivating microorganisms in fruit juices. However, this preservation method could interfere with the organoleptic characteristics of the product. Alternative methods have been proposed and bacteriocins such as nisin are potential candidates. However, the approval of bacteriocins as food additives is limited, especially in foods from vegetal origin. We aimed to verify the stability, the effect on physico-chemical properties, and the antimicrobial activity of nisin in different fruit juices. Nisin remained stable in fruit juices (cashew, soursop, peach, mango, passion fruit, orange, guava, and cupuassu) for at least 30 days at room or refrigerated temperature and did not cause any significant alterations in the physico-chemical characteristics of the juices. Besides, nisin favored the preservation of vitamin C content in juices. The antimicrobial activity of nisin was tested against Alicyclobacillus acidoterrestris, Bacillus cereus, Staphylococcus aureus and Listeria monocytogenes in cashew, soursop, peach, and mango juices. Nisin caused a 4-log reduction in viable cells of A. acidoterrestris in soursop, peach, and mango juices after 8h of incubation, and no viable cells were detected in cashew juices. After 24h of incubation in the presence of nisin, no viable cells were detected, independently of the juices. To S. aureus, at 24h of incubation in the presence of nisin, viable cells were only detected in mango juices, representing a 4-log decrease as compared with the control treatment. The number of viable cells of B. cereus at 24h of incubation in the presence of nisin represented at least a 4-log decrease compared to the control treatment. When the antimicrobial activity of nisin was tested against L. monocytogenes in cashew and soursop juices, no reduction in the viable cell number was observed compared to the control treatment after 24h of incubation. Viable cells were four and six times less than in the

  3. Chemical composition and antimicrobial activity of essential oils of Ocimum canum Sims. and Ocimum selloi Benth.

    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

  4. Activation of Cassava Stem Biochar by Physico-Chemical Method for Stimulating Cadmium Removal Efficiency from Aqueous Solution

    Songkrit Prapagdee; Somkiat Piyatiratitivorakul; Amorn Petsom

    2014-01-01

    Removal of Cadmium (Cd) from aqueous solution using biochar was considered a cost effective sorbent. Biochar quality and specification depend on its carbonization processes. In this study, the cassava stem biochars were produced at temperature of 300, 400 and 500 °C with slow pyrolysis technique. The biochar in each carbonization temperature was activated with physico-chemical treatments, pre-activated by 1.63M KOH solution then activated with second pyrolysis as same as first pyrolysis condi...

  5. A Rat α-Fetoprotein Binding Activity Prediction Model to Facilitate Assessment of the Endocrine Disruption Potential of Environmental Chemicals

    Hong, Huixiao; Shen, Jie; Ng, Hui Wen; Sakkiah, Sugunadevi; Ye, Hao; Ge, Weigong; Gong, Ping; Xiao, Wenming; Tong, Weida

    2016-01-01

    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. PMID:27023588

  6. Patch-clamp analysis of voltage-activated and chemically activated currents in the vomeronasal organ of Sternotherus odoratus (stinkpot/musk turtle)

    Fadool, D. A.; Wachowiak, M.; Brann, J. H.

    2001-01-01

    The electrophysiological basis of chemical communication in the specialized olfactory division of the vomeronasal (VN) organ is poorly understood. In total, 198 patch-clamp recordings were made from 42 animals (Sternotherus odoratus, the stinkpot/musk turtle) to study the electrically and chemically activated properties of VN neurons. The introduction of tetramethylrhodamine-conjugated dextran into the VN orifice permitted good visualization of the vomeronasal neural epithelium prior to disso...

  7. Chemical study of sediments from Solimoes and Negro rivers by Instrumental Neutron Activation Analysis (INAA)

    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)

  8. Phytotoxic activity and chemical composition of aqueous volatile fractions from Eucalyptus species.

    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.

  9. Agrice 1994-2000 - Activity report. Agriculture for chemicals and energy

    NONE

    2001-07-01

    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

  10. Chemical composition and insecticidal activity of plant essential oils from Benin against Anopheles gambiae (Giles)

    2013-01-01

    highly susceptible to all the other essential oils at the diagnostic dose. Conclusions C. citratus, E. tereticornis, E. citriodora, C. ambrosioides and C. schoenanthus are potential promising plant sources for alternative compounds to pyrethroids, for the control of the Anopheles malaria vector in Benin. The efficacy of their essential oils is possibly based on their chemical compositions in which major and/or minor compounds have reported insecticidal activities on various pests and disease vectors such as Anopheles. PMID:24298981

  11. Chemical composition and larvicidal activity of essential oil from Mentha spicata (Linn.) against three mosquito species.

    Govindarajan, M; Sivakumar, R; Rajeswari, M; Yogalakshmi, K

    2012-05-01

    Mosquitoes are blood-feeding insects and serve as the most important vectors for spreading human diseases such as malaria, yellow fever, dengue fever, and filariasis. The continued use of synthetic insecticides has resulted in resistance in mosquitoes. Synthetic insecticides are toxic and affect the environment by contaminating soil, water, and air, and then natural products may be an alternative to synthetic insecticides because they are effective, biodegradable, eco-friendly, and safe to environment. Botanical origin may serve as suitable alternative biocontrol techniques in the future. Mentha spicata, an edible and medicinal plant, is chiefly distributed in Southeast Asia and South Asia. In the present study, the toxicity of mosquito larvicidal activity of leaf essential oil (EO) and their major chemical constituents from Mentha spicata against Culex quinquefasciatus, Aedes aegypti, and Anopheles stephensi. The chemical composition of the leaf EO was analyzed using gas chromatography-mass spectroscopy (GC-MS). GC-MS revealed that the EO of M. spicata contained 18 compounds. The major chemical components identified were carvone (48.60%), cis-carveol (21.30%), and limonene (11.30%). The EO had a significant toxic effect against early third-stage larvae of C. quinquefasciatus, A. aegypti, and A. stephensi with LC(50) values of 62.62, 56.08, and 49.71 ppm and LC(90) values of 118.70, 110.28, and 100.99 ppm, respectively. The three major pure constituents extracted from the M. spicata leaf EO were also tested individually against three mosquito larvae. The LC(50) values of carvone, cis-carveol, and limonene appeared to be most effective against A. stephensi (LC(50) 19.33, 28.50, and 8.83 ppm) followed by A. aegypti (LC(50) 23.69, 32.88, and 12.01 ppm), and C. quinquefasciatus (LC(50) 25.47, 35.20, and 14.07 ppm). The results could be useful in search for newer, safer, and more effective natural larvicidal agents against C. quinquefasciatus, A. aegypti, and A

  12. Chemical Composition and Antifungal Activity of Ocimum basilicum L. Essential Oil

    Neveen Helmy Abou El-Soud

    2015-07-01

    Full Text Available BACKGROUND: The leaves of Ocimum basilicum L. (basil are used in traditional cuisine as spices; its essential oil has found a wide application in perfumery, dental products as well as antifungal agents. AIM: To assess the chemical composition as well as the in vitro antifungal activity of O. basilicum L. essential oil against Aspergillus flavus fungal growth and aflatoxin B1 production. MATERIAL AND METHODS: The essential oil of O. basilicum was obtained by hydrodistillation and analysed using gas chromatography (GC and GC coupled with mass spectrometry (GC/MS. The essential oil was tested for its effects on Aspergillus flavus (A. flavus mycelial growth and aflatoxin B1 production in Yeast Extract Sucrose (YES growth media. Aflatoxin B1 production was determined by high performance liquid chromatography (HPLC. RESULTS: Nineteen compounds, representing 96.7% of the total oil were identified. The main components were as follows: linalool (48.4%, 1,8-cineol (12.2%, eugenol (6.6%, methyl cinnamate (6.2%, α-cubebene (5.7%, caryophyllene (2.5%, β-ocimene (2.1% and α-farnesene (2.0%.The tested oil showed significant antifungal activity that was dependent on the used oil concentration. The complete inhibition of A. flavus growth was observed at 1000 ppm oil concentration, while marked inhibition of aflatoxin B1 production was observed at all oil concentrations tested (500, 750 and 1000 ppm. CONCLUSION: These results confirm the antifungal activities of O. basilicum L. oil and its potential use to cure mycotic infections and act as pharmaceutical preservative against A. flavus growth and aflatoxin B1 production.

  13. Chemical composition and biological activities of leaves of ziziphus mauritiana l. native to pakistan

    Ziziphus mauritiana L., is a fruit tree well known for its nutritional and medicinal benefits. The aim of the current study was to investigate the chemical composition as well as biological (antioxidant, antimicrobial, antitumor and anticancer) attributes of different solvent extracts from the leaves of Ziziphus mauritiana. It was established by colorimetric method that chloroform extract had greater amount of total phenolics (84.69 +- 0.92 micro g GAE/mg of extract), while methanol extract contained higher content of total flavonoids (46.94+-1.55 micro g QE/mg of extract). Meanwhile, methanol extract exhibited higher DPPH free radical scavenging potential (IC50 = 0.11 mg/mL) and antimicrobial (antibacterial and antifungal) activity among others. Overall, E. coli was noted to be the most resistant microbial strain against all the tested extracts. Chloroform extract showed strongest antitumor (IC50 = 70.74 micro g/mL) and anticancer activity (IC50 values of 27.78 and 18.32 micro g/mL against human cancer cell lines U937 and HCT-116, respectively) and significantly inhibited the viability of these cell lines. According to GC-MS analysis methyl stearate (15.59%), plamitic acid (38.55%) and micro-linolenic acid (26.45%) were identified as the major components of methanol, chloroform and hexane extracts, respectively in addition to presence of several other bioactives. The results of this study conclude that Z. mauritiana leaves extract with efficient biological activities can be explored for potential uses as antioxidant, antitumor and anticancer agents for pharmaceutical industry. (author)

  14. The monoamine oxidase inhibitory activity of essential oils obtained from Eryngium species and their chemical composition.

    Klein-Júnior, Luiz Carlos; Dos Santos Passos, Carolina; Tasso de Souza, Tiago Juliano; Gobbi de Bitencourt, Fernanda; Salton, Juliana; de Loreto Bordignon, Sérgio Augusto; Henriques, Amélia Teresinha

    2016-06-01

    Context Monoamine oxidase (MAO) inhibitors are used in the treatment of depression, anxiety disorders, and the symptomatic treatment of Parkinson's disease. Eryngium, the most representative of the Apiaceae family, is well known for the presence of essential oils (EOs), which have already demonstrated MAO inhibitory potential. Objective The objective of this study is to evaluate the MAO inhibitory capacity of the EOs obtained from Eryngium floribundum Cham. & Schlecht. (EF), E. eriophorum Cham. & Schlecht. (EE), E. nudicaule Lam. (EN), E. horridum Malme (EH), and E. pandanifolium Cham. & Schlecht. (EP). Materials and methods EOs were obtained from fresh whole plants by hydrodistillation (3 h). Chemical analyses were performed by GC/MS using apolar and polar columns, with oven temperature from 60 to 300 °C at 3 °C/min. The MAO-A and -B activities were evaluated in vitro by an end-point method using kynuramine as the substrate and mitochondrial suspension or human recombinant enzymes as the enzymatic source. DMSO 2%, clorgyline 10(-7) M, and pargyline 10(-6) M were used as controls. Results and discussion EFEO, EEEO, ENEO, EHEO, and EPEO GC/MS analysis showed (E)-caryophyllene (4.9-10.8%), germacrene D (0.6-35.1%), bicyclogermacrene (10.4-17.2), spathulenol (0.4-36.0%), and globulol (1.4-18.6%) as main constituents. None of the EOs inhibited MAO-A activity (4 and 40 μg/mL). However, EHEO inhibited MAO-B activity with an IC50 value of 5.65 μg/mL (1-200 μg/mL). Pentadecane (10 μM), its major constituent (53.5%), did not display significant MAO-B inhibition. Conclusion The study demonstrates the promising application of Eryngium species as a source of potential central nervous system bioactive secondary metabolites, specially related to neurodegenerative disorders. PMID:26810928

  15. Phase development in conventional and active belite cement pastes by Rietveld analysis and chemical constraints

    High belite cements may be an alternative to reduce CO2 emissions. Although CO2 emissions may be depleted up to 10%, unfortunately, the hydration reactivity of belite phases is slow which leads to low mechanical strengths at early ages. In order to enhance their hydraulic reactivity, the activation of these cements by doping with alkaline oxides has been proposed. Here, we have synthesised a laboratory belite clinker without activation (47 wt.% of β-C2S and 19 wt.% of αH'-C2S) and two alkaline oxide activated clinkers (one with 13 wt.% of β-C2S, 24 wt.% of αH'-C2S and 19 wt.% of α-C2S; and the second with 12 wt.% of β-C2S, 42 wt.% of αH'-C2S and 5 wt.% of α-C2S). We have also developed a methodology to analyse quantitatively the phase evolution of cement pastes and we have applied it to these high belite cements. Rietveld quantitative phase analysis of synchrotron X-ray powder diffraction data, together with chemical constraints, is used to determine the phase development up to 1 year of hydration in the belite cement pastes. β-C2S almost does not react during the first 3 months, meanwhile αH'-C2S reacts on average more than 50% in the same period. Moreover, the degree of reaction of α-C2S is slightly larger (on average about 70% after three months) than that of αH'-C2S. Full phase analyses are reported and discussed including the time evolution of amorphous phases and free water.

  16. Chemical Constituents and Insecticidal Activities of Ajania fruticulosa Essential Oil.

    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. PMID:27482698

  17. Chemical composition and cytotoxicity activity of the essential oil of Pterodon emarginatus

    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.

  18. Antirheumatoid Arthritis Activities and Chemical Compositions of Phenolic Compounds-Rich Fraction from Urtica atrichocaulis, an Endemic Plant to China

    Mengyue Wang

    2012-01-01

    Full Text Available Urtica atrichocaulis, an endemic plant to China, is commonly used to treat rheumatoid arthritis even though its pharmaceutical activities and chemical constituents were not studied. Herein, we reported our investigations on the chemical compositions of the phenolic compounds-rich fraction from U. atrichocaulis (TFUA and their antirheumatoid arthritis activities. We found that the TFUA significantly inhibited the adjuvant-induced rats arthritis, carrageenin-induced rats paw edema, cotton pellet-induced mice granuloma, and the acetic acid-induced mice writhing response. Our phytochemical investigations on the TFUA resulted in the first-time isolation and identification of 17 phenolic constituents and a bis (5-formylfurfuryl ether. The extensive HPLC analysis also revealed the chemical compositions of TFUA. Our further biological evaluation of the main phenolic components, individually and collectively, indicated that the antirheumatoid arthritis activities of TFUA were the combined effect of multiple phenolic constituents.

  19. Use of chemically activated cotton nut shell carbon for the removal of fluoride contaminated drinking water:Kinetics evaluation☆

    Rajan Mariappan; Raj Vairamuthu; Alagumuthu GanapathY

    2015-01-01

    Chemically activated cotton nut shell carbons (CTNSCs) were prepared by different chemicals and they were used for the removal of fluoride from aqueous solution. Effects of adsorption time, adsorbent dose, pH of the solution, initial concentration of fluoride, and temperature of the solution were studied with equilibrium, ther-modynamics and kinetics of the adsorption process by various CTNSC adsorbents. It showed that the chemical y activated CTNSCs can effectively remove fluoride from the solution. The adsorption equilibrium data correlate well with the Freundlich isotherm model. The adsorption of fluoride by the chemical y activated CTNSC is spon-taneous and endothermic in nature. The pseudo first order, pseudo second order and intra particle diffusion kinetic models were applied to test the experimental data. The pseudo second order kinetic model provided a better correlation of the experimental data in comparison with the pseudo-first-order and intra particle diffusion models. A mechanism of fluoride adsorption associating chemisorption and physisorption processes is presented allowing the discussion of the variations in adsorption behavior between these materials in terms of specific surface area and porosity. These data suggest that chemically activated CTNSCs are promising materials for fluoride sorption.

  20. Energy Efficient Catalytic Activation of Hydrogen peroxide for Green Chemical Processes: Final Report

    Collins, Terrence J.; Horwitz, Colin

    2004-11-12

    A new, highly energy efficient approach for using catalytic oxidation chemistry in multiple fields of technology has been pursued. The new catalysts, called TAML® activators, catalyze the reactions of hydrogen peroxide and other oxidants for the exceptionally rapid decontamination of noninfectious simulants (B. atrophaeus) of anthrax spores, for the energy efficient decontamination of thiophosphate pesticides, for the facile, low temperature removal of color and organochlorines from pulp and paper mill effluent, for the bleaching of dyes from textile mill effluents, and for the removal of recalcitrant dibenzothiophene compounds from diesel and gasoline fuels. Highlights include the following: 1) A 7-log kill of Bacillus atrophaeus spores has been achieved unambiguously in water under ambient conditions within 15 minutes. 2) The rapid total degradation under ambient conditions of four thiophosphate pesticides and phosphonate degradation intermediates has been achieved on treatment with TAML/peroxide, opening up potential applications of the decontamination system for phosphonate structured chemical warfare agents, for inexpensive, easy to perform degradation of stored and aged pesticide stocks (especially in Africa and Asia), for remediation of polluted sites and water bodies, and for the destruction of chemical warfare agent stockpiles. 3) A mill trial conducted in a Pennsylvanian bleached kraft pulp mill has established that TAML catalyst injected into an alkaline peroxide bleach tower can significantly lower color from the effluent stream promising a new, more cost effective, energy-saving approach for color remediation adding further evidence of the value and diverse engineering capacity of the approach to other field trials conducted on effluent streams as they exit the bleach plant. 4) Dibenzothiophenes (DBTs), including 4,6-dimethyldibenzothiophene, the most recalcitrant sulfur compounds in diesel and gasoline, can be completely removed from model gasoline

  1. Production of granular activated carbon from agricultural wastes and determination of their physical, chemical and adsorption properties

    Ayguen, A.; Duman, I. [Istanbul Technical Univ., Inst. of Science and Technology, Dept. of Metallurgical Engineering, Istanbul (Turkey); Yenisoy-Karakas, S. [TUeBITAK Marmara Research Center (MRC), Materials and Chemical Technologies Research Inst., Gebze Kocaeli (Turkey)

    2004-07-01

    The aim of this study is to produce activated carbons with good mechanical strength and high adsorption capacities toward various organics from food wastes such as walnut, almond, hazelnut shells and apricot stones. Turkey has huge amounts of these wastes in canning industry. The chemical activation with ZnCl{sub 2} was preferred to manufacture activated carbons. The best activation temperature and time were determined. Granular activated carbons were discussed with respect to their physical, chemical, surface area and adsorption properties. For all raw materials, the specific surface areas of greater than 730 m{sup 2} g{sup -1} were reached. As a result of the adsorption studies, adsorption capacities were in order of hazelnut> apricot stones> walnut> almond. The correlation coefficients obtained from Langmuir and Freundlich isotherms are in good agreement with the experimental results. (orig.)

  2. Chemical and structural evaluation of activated carbon prepared from jute sticks for Brilliant Green dye removal from aqueous solution.

    Asadullah, Mohammad; Asaduzzaman, Mohammad; Kabir, Mohammad Shajahan; Mostofa, Mohammad Golam; Miyazawa, Tomohisa

    2010-02-15

    Activated carbons have been prepared from jute sticks by chemical activation using ZnCl(2) and physical activation using steam for the removal of Brilliant Green dye from aqueous solution. The activated carbons and charcoal prepared from jute sticks were characterized by evaluating the surface chemistry, structural features and surface morphology. The maximum BET surface area was obtained to be 2304 m(2)/g for chemical activated carbon (ACC) while it is 730 and 80 m(2)/g for steam activated carbon (ACS) and charcoal, respectively. The FT-IR spectra exhibited that the pyrolysis and steam activation of jute sticks resulted in the release of aliphatic and O-containing functional groups by thermal effect. However, the release of functional groups is the effect of chemical reaction in the ZnCl(2) activation process. A honeycomb-type carbon structure in ACC was formed as observed on SEM images. Although charcoal and ACC were prepared at 500 degrees C the ACC exhibited much lower Raman sensitivity due to the formation of condensed aromatic ring systems. Due to high surface area and high porous structure with abundance of functional groups, the ACC adsorbed dye molecules with much higher efficiency than those of ACS and charcoal. PMID:19815339

  3. Adaptive Neuro-Fuzzy Inference System Applied QSAR with Quantum Chemical Descriptors for Predicting Radical Scavenging Activities of Carotenoids.

    Jhin, Changho; Hwang, Keum Taek

    2015-01-01

    One of the physiological characteristics of carotenoids is their radical scavenging activity. In this study, the relationship between radical scavenging activities and quantum chemical descriptors of carotenoids was determined. Adaptive neuro-fuzzy inference system (ANFIS) applied quantitative structure-activity relationship models (QSAR) were also developed for predicting and comparing radical scavenging activities of carotenoids. Semi-empirical PM6 and PM7 quantum chemical calculations were done by MOPAC. Ionisation energies of neutral and monovalent cationic carotenoids and the product of chemical potentials of neutral and monovalent cationic carotenoids were significantly correlated with the radical scavenging activities, and consequently these descriptors were used as independent variables for the QSAR study. The ANFIS applied QSAR models were developed with two triangular-shaped input membership functions made for each of the independent variables and optimised by a backpropagation method. High prediction efficiencies were achieved by the ANFIS applied QSAR. The R-square values of the developed QSAR models with the variables calculated by PM6 and PM7 methods were 0.921 and 0.902, respectively. The results of this study demonstrated reliabilities of the selected quantum chemical descriptors and the significance of QSAR models. PMID:26474167

  4. Adaptive Neuro-Fuzzy Inference System Applied QSAR with Quantum Chemical Descriptors for Predicting Radical Scavenging Activities of Carotenoids.

    Changho Jhin

    Full Text Available One of the physiological characteristics of carotenoids is their radical scavenging activity. In this study, the relationship between radical scavenging activities and quantum chemical descriptors of carotenoids was determined. Adaptive neuro-fuzzy inference system (ANFIS applied quantitative structure-activity relationship models (QSAR were also developed for predicting and comparing radical scavenging activities of carotenoids. Semi-empirical PM6 and PM7 quantum chemical calculations were done by MOPAC. Ionisation energies of neutral and monovalent cationic carotenoids and the product of chemical potentials of neutral and monovalent cationic carotenoids were significantly correlated with the radical scavenging activities, and consequently these descriptors were used as independent variables for the QSAR study. The ANFIS applied QSAR models were developed with two triangular-shaped input membership functions made for each of the independent variables and optimised by a backpropagation method. High prediction efficiencies were achieved by the ANFIS applied QSAR. The R-square values of the developed QSAR models with the variables calculated by PM6 and PM7 methods were 0.921 and 0.902, respectively. The results of this study demonstrated reliabilities of the selected quantum chemical descriptors and the significance of QSAR models.

  5. Antibacterial activity chemical composition relationship of the essential oils from cultivated plants from Serbia

    Stanković Nemanja S.

    2011-01-01

    Full Text Available The antibacterial effects of essential oils from Serbian cultivated plants, Thymus vulgaris L. (Lamiace and Lavandula angustifolia L. (Lamiace on different bacteria were investigated, with an emphasis on an antibacterial activity-chemical composition relationship. Essential oil was obtained from airdried aerial parts of the plants by hydrodistillation for 3 h using a Clevenger-type apparatus. The essential oil analyses were performed simultaneously by gas chromatography (GC and gas chromatography-mass spectrometry (GC-MS systems. The main constituents of thyme oil were thymol (59.95% and p-cymene (18.34%. Linalyl acetate (38.23% and linalool (35.01% were main compounds in lavender oil. The antibacterial activity of the essential oils samples was tested towards 5 different bacteria: laboratory control strain obtained from the American Type Culture Collection and clinical isolates from different pathogenic media. Gram negative bacteria were represented by Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 43895 and Salmonella enteretidis ATCC 9027 while researched Gram positive strains were Bacillus cereus ATCC 8739 and Staphylococcus aureus ATCC 25923. A broth microdilution method was used to determine the minimum inhibitory concentration (MIC and minimum bactericidal concentration (MBC. Essential oils from thyme have been found to have antimicrobial activity against all microorganisms tested, with a range of MIC values from 0.025 to 0.10 l/ml and MBC values from 0.05 to 0.78 l/ml. Lavender oils demonstrated MIC values from 0.025 to 0.20 l/ml and MBC values from 0.05 and 0.78 l/ml. Reference antibiotic tetracycline was active in concentrations between 0.025 and 0.05 l/ml. The Gram-positive bacteria were more sensitive to the essential oil of thyme, while Gram-negative bacteria were more sensitive to the essential oil of lavender. Essential oils from thyme and lavender may be used at low concentrations for prevention and treatment of

  6. Electric Current Activated Combustion Synthesis and Chemical Ovens Under Terrestrial and Reduced Gravity Conditions

    Unuvar, C.; Fredrick, D.; Anselmi-Tamburini, U.; Manerbino, A.; Guigne, J. Y.; Munir, Z. A.; Shaw, B. D.

    2004-01-01

    Combustion synthesis (CS) generally involves mixing reactants together (e.g., metal powders) and igniting the mixture. Typically, a reaction wave will pass through the sample. In field activated combustion synthesis (FACS), the addition of an electric field has a marked effect on the dynamics of wave propagation and on the nature, composition, and homogeneity of the product as well as capillary flow, mass-transport in porous media, and Marangoni flows, which are influenced by gravity. The objective is to understand the role of an electric field in CS reactions under conditions where gravity-related effects are suppressed or altered. The systems being studied are Ti+Al and Ti+3Al. Two different ignition orientations have been used to observe effects of gravity when one of the reactants becomes molten. This consequentially influences the position and concentration of the electric current, which in turn influences the entire process. Experiments have also been performed in microgravity conditions. This process has been named Microgravity Field Activated Combustion Synthesis (MFACS). Effects of gravity have been demonstrated, where the reaction wave temperature and velocity demonstrate considerable differences besides the changes of combustion mechanisms with the different high currents applied. Also the threshold for the formation of a stable reaction wave is increased under zero gravity conditions. Electric current was also utilized with a chemical oven technique, where inserts of aluminum with minute amounts of tungsten and tantalum were used to allow observation of effects of settling of the higher density solid particles in liquid aluminum at the present temperature profile and wave velocity of the reaction.

  7. Electrochemical sensing chemical oxygen demand based on the catalytic activity of cobalt oxide film

    Highlights: ► A novel electrochemical sensor was developed for COD using cobalt oxide film. ► It exhibited high sensitivity, rapid response, good simplicity and practicability. ► It was used in numerous water samples, and accuracy was tested by standard method. - Abstract: Cobalt oxide sensing film was in situ prepared on glassy carbon electrode surface via constant potential oxidation. Controlling at 0.8 V in NaOH solution, the high-valence cobalt catalytically oxidized the reduced compounds, decreasing its surface amount and current signal. The current decline was used as the response signal of chemical oxygen demand (COD) because COD represents the summation of reduced compounds in water. The surface morphology and electrocatalytic activity of cobalt oxide were readily tuned by variation of deposition potential, time, medium and Co2+ concentration. As confirmed from the atomic force microscopy measurements, the cobalt oxide film, that prepared at 1.3 V for 40 s in pH 4.6 acetate buffer containing 10 mM Co(NO3)2, possesses large surface roughness and numerous three-dimensional structures. Electrochemical tests indicated that the prepared cobalt oxide exhibited high electrocatalytic activity to the reduced compounds, accompanied with strong COD signal enhancement. As a result, a novel electrochemical sensor with high sensitivity, rapid response and operational simplicity was developed for COD. The detection limit was as low as 1.1 mg L−1. The analytical application was studied using a large number of lake water samples, and the accuracy was tested by standard method.

  8. Wireless micropower instrumentation for multimodal acquisition of electrical and chemical neural activity.

    Mollazadeh, M; Murari, K; Cauwenberghs, G; Thakor, N

    2009-12-01

    The intricate coupling between electrical and chemical activity in neural pathways of the central nervous system, and the implication of this coupling in neuropathologies, such as Parkinson's disease, motivates simultaneous monitoring of neurochemical and neuropotential signals. However, to date, neurochemical sensing has been lacking in integrated clinical instrumentation as well as in brain-computer interfaces (BCI). Here, we present an integrated system capable of continuous acquisition of data modalities in awake, behaving subjects. It features one channel each of a configurable neuropotential and a neurochemical acquisition system. The electrophysiological channel is comprised of a 40-dB gain, fully differential amplifier with tunable bandwidth from 140 Hz to 8.2 kHz. The amplifier offers input-referred noise below 2 muV rms for all bandwidth settings. The neurochemical module features a picoampere sensitivity potentiostat with a dynamic range spanning six decades from picoamperes to microamperes. Both systems have independent on-chip, configurable DeltaSigma analog-to-digital converters (ADCs) with programmable digital gain and resolution. The system was also interfaced to a wireless power harvesting and telemetry module capable of powering up the circuits, providing clocks for ADC operation, and telemetering out the data at up to 32 kb/s over 3.5 cm with a bit-error rate of less than 10(-5). Characterization and experimental results from the electrophysiological and neurochemical modules as well as the full system are presented. PMID:23853286

  9. Chemical weathering in active mountain belts controlled by stochastic bedrock landsliding

    Emberson, Robert; Hovius, Niels; Galy, Albert; Marc, Odin

    2016-01-01

    A link between chemical weathering and physical erosion exists at the catchment scale over a wide range of erosion rates. However, in mountain environments, where erosion rates are highest, weathering may be kinetically limited and therefore decoupled from erosion. In active mountain belts, erosion is driven by bedrock landsliding at rates that depend strongly on the occurrence of extreme rainfall or seismicity. Although landslides affect only a small proportion of the landscape, bedrock landsliding can promote the collection and slow percolation of surface runoff in highly fragmented rock debris and create favourable conditions for weathering. Here we show from analysis of surface water chemistry in the Southern Alps of New Zealand that weathering in bedrock landslides controls the variability in solute load of these mountain rivers. We find that systematic patterns in surface water chemistry are strongly associated with landslide occurrence at scales from a single hillslope to an entire mountain belt, and that landslides boost weathering rates and river solute loads over decades. We conclude that landslides couple erosion and weathering in fast-eroding uplands and, thus, mountain weathering is a stochastic process that is sensitive to climatic and tectonic controls on mass wasting processes.

  10. CHEMICAL COMPOSITION AND ANTIBACTERIAL ACTIVITY OF SOME MEDICINAL PLANTS FROM LAMIACEAE FAMILY.

    Kozłowska, Mariola; Laudy, Agnieszka E; Przybył, Jarosław; Ziarno, Małgorzata; Majewska, Ewa

    2015-01-01

    Chemical composition and antibacterial activity of aqueous (ethanolic and methanolic) extracts from herbs often used in Polish cuisine and traditional herbal medicine including thyme (Thymus vulgaris L.), rosemary (Rosmarinus officinalis L.), oregano (Origanum vulgare L.), peppermint (Mentha piperita L.) and sage (Salvia officinalis L.) were compared. The aqueous ethanolic extracts contained slightly higher levels of phenolics compared to the aqueous methanolic extracts. In turn, GC-MS analysis showed that the aqueous methanolic extracts of thyme, rosemary and sage contained several additional compounds such as eugenol or ledol. The present studies also indicated that the bacterial species applied in the experiment exhibited different sensitivities towards tested extracts. Staphylococcus aureus strains were found to be the most sensitive bacteria to aqueous (ethanolic and methanolic) rosemary and sage extracts and aqueous methanolic thyme extract. Klebsiella pneumoniae ATCC 13883 and Proteus vulgaris NCTC 4635 were more susceptible to the aqueous methanolic thyme extract. However, Listeria monocytogenes 1043S was the most sensitive to the aqueous ethanolic rosemary extract. Gram-positive bacteria were generally more sensitive to the tested extracts than Gram-negative ones. PMID:26647633

  11. Neutron activation analysis for assessing chemical composition of dry dog foods

    Brazil holds the second largest population of domestic dogs in the world, with 33 million dogs, only behind the United States. The annual consumption of dog food in the country is 1.75 million tons, corresponding to the World's sixth in trade turnover. Dog food is supposed to be a complete and balanced diet, formulated with high quality ingredients. All nutrients and minerals required for an adequate nutrition of dogs are added to the formulation to ensure longevity and welfare. In this context, the present study aimed at assessing the chemical composition of dry dog foods commercialized in Brazil. Thirty-four samples were acquired in the local market of Piracicaba and analyzed by instrumental neutron activation analysis (INAA) to determine the elements As, Br, Ca, Co, Cr, Cs, Fe, K, La, Na, Rb, Sb, Sc, Se, U, and Zn. In general, the concentrations of Ca, Fe, K, Na, and Zn complied with the values required by the Association of American Feed Control Officials (AAFCO). To evaluate the safety of dog food commercialized in Brazil, further investigation is necessary to better understand the presence of toxic elements found in this study, i.e. Sb and U. INAA was useful for the screening analysis of different types and brands of dry dog foods for the determination of both essential and toxic elements. (author)

  12. Chemical Composition and Antibacterial and Cytotoxic Activities of Allium hirtifolium Boiss

    Salmiah Ismail

    2013-01-01

    Full Text Available Allium hirtifolium Boiss. known as Persian shallot, is a spice used as a traditional medicine in Iran and, Mediterranean region. In this study, the chemical composition of the hydromethanolic extract of this plant was analyzed using GC/MS. The result showed that 9-hexadecenoic acid, 11,14-eicosadienoic acid, and n-hexadecanoic acid are the main constituents. The antibacterial activity of the shallot extract was also examined by disk diffusion and microdilution broth assays. It was demonstrated that Persian shallot hydromethanolic extract was effective against 10 different species of pathogenic bacteria including methicillin resistant Staphylococcus aureus (MRSA, methicillin sensitive Staphylococcus aureus (MSSA, Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pneumoniae, Escherichia coli, Escherichia coli O157:H7, Salmonella typhimurium, Proteus mirabilis, and Klebsiella pneumoniae. Specifically, the minimum concentration of the extract which inhibited bacterial growth (MIC values was 1.88 mg/mL for most of the gram-positive bacteria. This concentration was not much different from the concentration that was safe for mammalian cells (1.50 mg/mL suggesting that the hydromethanolic extract of Persian shallot may be a safe and strong antibacterial agent.

  13. Physico-Chemical Properties, Antioxidant Activity and Mineral Contents of Pineapple Genotypes Grown in China

    Xin-Hua Lu

    2014-06-01

    Full Text Available The fruit physico-chemical properties, antioxidant activity and mineral contents of 26 pineapple [Ananas comosus (L. Merr.] genotypes grown in China were measured. The results showed great quantitative differences in the composition of these pineapple genotypes. Sucrose was the dominant sugar in all 26 genotypes, while citric acid was the principal organic acid. Potassium, calcium and magnesium were the major mineral constituents. The ascorbic acid (AsA content ranged from 5.08 to 33.57 mg/100 g fresh weight (FW, while the total phenolic (TP content varied from 31.48 to 77.55 mg gallic acid equivalents (GAE/100 g FW. The two parameters in the predominant cultivars Comte de Paris and Smooth Cayenne were relative low. However, MD-2 indicated the highest AsA and TP contents (33.57 mg/100 g and 77.55 mg GAE/100 g FM, respectively, and it also showed the strongest antioxidant capacity 22.85 and 17.30 μmol TE/g FW using DPPH and TEAC methods, respectively. The antioxidant capacity of pineapple was correlated with the contents of phenolics, flavonoids and AsA. The present study provided important information for the further application of those pineapple genotypes.

  14. Chemical Composition and Antibacterial and Cytotoxic Activities of Allium hirtifolium Boiss

    Ismail, Salmiah; Jalilian, Farid Azizi; Talebpour, Amir Hossein; Zargar, Mohsen; Shameli, Kamyar; Sekawi, Zamberi; Jahanshiri, Fatemeh

    2013-01-01

    Allium hirtifolium Boiss. known as Persian shallot, is a spice used as a traditional medicine in Iran and, Mediterranean region. In this study, the chemical composition of the hydromethanolic extract of this plant was analyzed using GC/MS. The result showed that 9-hexadecenoic acid, 11,14-eicosadienoic acid, and n-hexadecanoic acid are the main constituents. The antibacterial activity of the shallot extract was also examined by disk diffusion and microdilution broth assays. It was demonstrated that Persian shallot hydromethanolic extract was effective against 10 different species of pathogenic bacteria including methicillin resistant Staphylococcus aureus (MRSA), methicillin sensitive Staphylococcus aureus (MSSA), Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pneumoniae, Escherichia coli, Escherichia coli O157:H7, Salmonella typhimurium, Proteus mirabilis, and Klebsiella pneumoniae. Specifically, the minimum concentration of the extract which inhibited bacterial growth (MIC values) was 1.88 mg/mL for most of the gram-positive bacteria. This concentration was not much different from the concentration that was safe for mammalian cells (1.50 mg/mL) suggesting that the hydromethanolic extract of Persian shallot may be a safe and strong antibacterial agent. PMID:23484141

  15. Chemical composition and cytotoxic activity of the polysaccharide fractions in Sarcodon imbricatus (Basidiomycota

    Katarzyna Sułkowska-Ziaja

    2013-12-01

    Full Text Available The aim of the study was chemical analysis of polysaccharide fractions from sporocarps of Sarcodon imbricatus collected in natural sites and from the mycelium of in vitro cultures. Three polysaccharide fractions (FOI, FOII, FOIII were isolated from sporocarps and two (FKI, FKII from in vitro cultures. Qualitative analysis by HPLC method showed that they are composed of galactose and fucose (FOI, FKI or glucose and fucose (FOII, FKII. FOIII fraction of the sporocarps consisted of glucose only. Molecular weights of isolated fractions ranged from 3.8 to 16.3 kDa for fractions from the sporocarps and from 5.8 to 14.7 kDa for that ones isolated from in vitro culture. The total percentage of sugar content for all fractions ranged from 97.8% to 99.1%. The percentage of uronic acids contents in acidic fractions was 2.6% and 2.7% for the FOI and FKI respectively. The work included also an assessment of cytotoxic activity of polysaccharide fractions in relation to tumor cell lines of human breast cancer MCV-7. FOI polysaccharide fraction of the sporocarps inhibited the growth of cancer cells in 50% compared to the control at a concentration of 0.0125%, while the polysaccharide fraction FKI from in vitro cultures inhibited cell growth in a concentration of 0.016%.

  16. Iodinated derivatives of vasoactive intestinal peptide (VIP), PHI and PHM: purification, chemical characterization and biological activity

    The iodination of vasoactive intestinal peptide (VIP) was studied, using a variety of enzymatic and chemical iodination methods. Reversed phase high performance liquid chromatography (HPLC) was used to purify the reaction products. The lactoperoxidase-glucose oxidase method gave excellent results in terms of reproducibility, iodine incorporation, and yield of the non-oxidized products [Tyr(I)10]VIP and [Tyr(I)22]VIP, and was used to prepare both 125I and 127I labelled derivatives. In both cases, direct application to HPLC and a single column system were used. Although the oxidized peptides [Tyr(I)10,Met(O)17]VIP and [Tyr(I)22,Met(O)17]VIP could be generated to varying degrees directly by iodination of VIP, these were most conveniently prepared by iodination of [Met(O)17]VIP. Iodinated derivatives of the homologous peptides PHI and PHM were likewise prepared by rapid, one-step HPLC procedures. The site and degree of iodination were determined by HPLC peptide mapping of tryptic digests and amino acid analyses, and in the case of [Tyr(I)10]VIP also by sequencing. The vasorelaxant activities of the iodinated peptides in bovine cerebral artery preparations did not differ significantly from those of the corresponding noniodinated peptides, with the exception of [Tyr(I)10,Met(O)17]VIP and [Tyr(I)22,Met(O)17]VIP which, unlike [Met(O)17]VIP itself, had slightly lower potency than VIP

  17. Influences of the chemical structure of entrainers on the activity coefficients in presence of biodiesel

    In this work we analyzed the strength of the intermolecular forces between biodiesel and the entrainer and their influence on the entrainer's ability to interact with biodiesel. Furthermore we investigated the influence of the chemical structure of an entrainer to the interaction with biodiesel. For this purpose the activity coefficients γ∞ at infinite dilution of acids, aldehydes, ketones and alcohols in biodiesel were measured with the method of headspace gas chromatography (HSGC). Short-chained acids showed the highest interaction of the analyzed entrainers caused by their ability to build hydrogen bonds with biodiesel. Increased chain length of the acids cause reduced interaction with biodiesel, which is mainly due to the higher obstruction of the acid molecule and therefore the reduced ability to build hydrogen bonds with biodiesel. Aldehydes, ketones and alcohols showed lower interaction with biodiesel compared to the acids. Longer-chained alcohols showed increased interaction with biodiesel due to the raised London Forces and an inductive +I effect of the molecule chain.

  18. Consequences of New Approach to Chemical Stability Tests to Active Pharmaceutical Ingredients.

    Jamrógiewicz, Marzena

    2016-01-01

    There is a great need of broaden look on stability tests of active pharmaceutical ingredients (APIs) in comparison with current requirements contained in pharmacopeia. By usage of many modern analytical methods the conception of monitoring the changes of APIs during initial stage of their exposure to harmful factors has been developed. New knowledge must be acquired in terms of identification of each degradation products, especially volatile ones. Further research as toxicology prediction during in silico studies of determined and identified degradation products is necessary. In silico methods are known as computational toxicology or computer-assisted technologies which are used for predicting toxicology of pharmaceutical substances such as impurities or degradation products. This is a specialized software and databases intended to calculate probability of genotoxicity or mutagenicity of these substances through a chemical structure-based screening process and algorithm specific to a given software program. Applying of new analytical approach is proposed as the usage of PAT tools, XRD, HS-SPME GC-MS/MS, LC-MS/MS for stability testing. Described improvements should be taken into account in case of each drug existing already in the market as well as being implemented as new one. PMID:26955356

  19. In vivo antileishmanial activity and chemical profile of polar extract from Selaginella sellowii

    Dayane Priscilla de Souza Queiroz

    2016-01-01

    Full Text Available The polar hydroethanolic extract from Selaginella sellowii(SSPHE has been previously proven active on intracellular amastigotes (in vitro test and now was tested on hamsters infected with Leishmania (Leishmania amazonensis (in vivo test. SSPHE suppressed a 100% of the parasite load in the infection site and draining lymph nodes at an intralesional dose of 50 mg/kg/day × 5, which was similar to the results observed in hamsters treated with N-methylglucamine antimonate (Sb (28 mg/Kg/day × 5. When orally administered, SSPHE (50 mg/kg/day × 20 suppressed 99.2% of the parasite load in infected footpads, while Sb suppressed 98.5%. SSPHE also enhanced the release of nitric oxide through the intralesional route in comparison to Sb. The chemical fingerprint of SSPHE by high-performance liquid chromatography with diode-array detection and tandem mass spectrometry showed the presence of biflavonoids and high molecular weight phenylpropanoid glycosides. These compounds may have a synergistic action in vivo. Histopathological study revealed that the intralesional treatment with SSPHE induced an intense inflammatory infiltrate, composed mainly of mononuclear cells. The present findings reinforce the potential of this natural product as a source of future drug candidates for American cutaneous leishmaniasis.

  20. Influence of the pore structure and surface chemical properties of activated carbon on the adsorption of mercury from aqueous solutions

    Highlights: • Activated carbons with different pore structure and surface chemical properties were prepared by modification process. • HgCl2 as a pollution target to evaluate the adsorption performance. • Influence of pore structure and surface chemical properties of activated carbon on adsorption of mercury was investigated. -- Abstract: Reactivation and chemical modification were used to obtain modified activated carbons with different pore structure and surface chemical properties. The samples were characterized by nitrogen absorption–desorption, Fourier transform infrared spectroscopy and the Bothem method. Using mercury chloride as the target pollutant, the Hg2+ adsorption ability of samples was investigated. The results show that the Hg2+ adsorption capacity of samples increased significantly with increases in micropores and acidic functional groups and that the adsorption process was exothermic. Different models and thermodynamic parameters were evaluated to establish the mechanisms. It was concluded that the adsorption occurred through a monolayer mechanism by a two-speed process involving both rapid adsorption and slow adsorption. The adsorption rate was determined by chemical reaction

  1. Chemical Hygiene Plan for Onsite Measurement and Sample Shipping Facility Activities

    This chemical hygiene plan presents the requirements established to ensure the protection of employee health while performing work in mobile laboratories, the sample shipping facility, and at the onsite radiological counting facility. This document presents the measures to be taken to promote safe work practices and to minimize worker exposure to hazardous chemicals. Specific hazardous chemicals present in the mobile laboratories, the sample shipping facility, and in the radiological counting facility are presented in Appendices A through G

  2. The potential of computer-based quantitative structure activity approaches for predicting acute toxicity of chemicals

    Zvinavashe, E.

    2008-01-01

    Within the EU, the management of the risks of chemicals currently falls under a new legislation called Registration, Evaluation, and Authorization of Chemicals (REACH). Within the next 10 years, existing (eco)toxicological data gaps for the more than 100 000 chemicals on the European Inventory of Existing Commercial Substances (EINECS) should be filled. The challenge is to provide this toxicity information in a fast, cost effective manner, avoiding the use of experimental animals as much as p...

  3. Endocrine active chemicals and endocrine disruption in Minnesota streams and lakes: implications for aquatic resources, 1994-2008

    Lee, Kathy E.; Schoenfuss, Heiko L.; Barber, Larry B.; Writer, Jeff H.; Blazer, Vicki; Keisling, Richard L.; Ferrey, Mark L.

    2010-01-01

    The U.S. Geological Survey, in cooperation with St. Cloud State University, Minnesota Department of Health, Minnesota Pollution Control Agency, Minnesota Department of Natural Resources, Metropolitan Council Environmental Services, and the University of Minnesota, has conducted field monitoring studies and laboratory research to determine the presence of endocrine active chemicals and the incidence of endocrine disruption in Minnesota streams and lakes during 1994–2008. Endocrine active chemicals are chemicals that interfere with the natural regulation of endocrine systems, and may mimic or block the function of natural hormones in fish or other organisms. This interference commonly is referred to as endocrine disruption. Indicators of endocrine disruption in fish include vitellogenin (female egg yolk protein normally expressed in female fish) in male fish, oocytes present in male fish testes, reduced reproductive success, and changes in reproductive behavior.

  4. Chemical profile and antimicrobial activity of Boldo (Peumus boldus Molina extracts obtained by compressed carbon dioxide extraction

    M. Mazutti

    2008-06-01

    Full Text Available This work reports the effects of temperature (20 to 50ºC and pressure (100 to 250 bar on the extraction yield, chemical characteristics and antimicrobial activity of extracts of Peumus boldus Molina obtained by compressed carbon dioxide extraction. Results showed that the extraction variables affect the extraction yield and the chemical distribution of the major compounds present in the extracts. The extracts were chemically analyzed with regard to 1,8-cineole, trans-sabinene, pinocarveol, pinocarvone, 4-terpineol, ascaridole, piperitone oxide, limonene dioxide and n-eicosane in a GC/MSD. Antimicrobial tests demonstrated that the high-pressure CO2 extracts had activity against 13 bacteria and that better action was verified with extracts obtained at a lower CO2 extraction density and a higher temperature.

  5. Change in chemical constituents and free radical-scavenging activity during Pear (Pyrus pyrifolia) cultivar fruit development.

    Cho, Jeong-Yong; Lee, Sang-Hyun; Kim, Eun Hee; Yun, Hae Rim; Jeong, Hang Yeon; Lee, Yu Geon; Kim, Wol-Soo; Moon, Jae-Hak

    2015-01-01

    Changes in chemical constituent contents and DPPH radical-scavenging activity in fruits of pear (Pyrus pyrifolia) cultivars during the development were investigated. The fruits of seven cultivars (cv. Niitaka, Chuhwangbae, Wonhwang, Hwangkeumbae, Hwasan, Manpungbae, and Imamuraaki) were collected at 15-day intervals after day 20 of florescence. Vitamins (ascorbic acid and α-tocopherol), arbutin, chlorogenic acid, malaxinic acid, total caffeic acid, total flavonoids, and total phenolics were the highest in immature pear fruit on day 20 after florescence among samples at different growth stages. All of these compounds decreased gradually in the fruit during the development. Immature pear fruit on day 35 or 50 after florescence exhibited higher free radical-scavenging activity than that at other times, although activities were slightly different among cultivars. The chemical constituent contents and free radical-scavenging activity were largely different among immature fruits of the pear cultivars, but small differences were observed when they matured. PMID:25348501

  6. IN VITRO TISSUE CULTURE, CHEMICAL COMPOSITION AND BIOLOGICAL ACTIVITY OF PLUMBAGO SCANDENS L.

    Manuel Farcio-Villarreal

    2015-03-01

    Full Text Available A protocol was developed for the micropropagation of Plumbago scandens L. from the shoot tip and node explants.The best response of shoot elongation (10.18±2.01 mm was observed on MS basal medium supplemented with 0.02 mg/L IAA – 0.02 mg/L GA3. The maximum number of root induction (10.0±2.21 and shoot elongation (8.24±3.24 mm was observed on medium containing 0.01 mg/L IBA and 0.01 mg/L GA3. The in vitro propagated plants were transferred to soil with 80% survival rate. Profuse compact callus was induced and proliferated from several explants (cotyledons, internodes, hypocotyls and roots cultured on MS medium supplemented with all the combinations of 2,4-D – GA3 or 2,4-D alone and combinations of IAA – BAP or IAA alone, and the highest percentage of friable callus (90% were induced in the sections of compact callus using 2.0 mg/L IAA – 0.02 mg/L BAP – 0.5 mg/L GA3.The qualitative determination of chemical constituents in the extracts was evaluated by a gas chromatography coupled to a mass spectrometry, and it was verified the presence of plumbagin only in root extracts but not in in vitro plantlets.The antibacterial activity of root extracts against various pathogenic bacteria, and the minimum inhibitory concentrations (MICs was determined. Chloroform extracts showed good antibacterial activity against Neisseria gonorrhoeae between 0.4 to 1.0 mg/L with 20.4 to 30.0 mm (diameter zone of inhibition; inhibition against Staphylococcus aureus was moderate, and lower against Escherichia coli. Chloroform extracts had the lowest MICs for N. gonorrhoeae (<0.1 mg/mL per disc, and the activities against S. aureus (MIC 0.2 mg/mL and E. coli (MIC 0.4 mg/mL were less pronounced.

  7. Comparison of the Chemical Composition and Antimicrobial Activity of Thymus serpyllum Essential Oils

    Aneta WESOŁOWSKA

    2015-12-01

    Full Text Available The chemical composition of the essential oils obtained by hydrodistillation from the aerial parts of Thymus serpyllum and Thymus serpyllum ‘Aureus’ has been investigated by gas chromatography-mass spectrometry (GC-MS. Forty-seven compounds (99.67% of the total oil were identified in the essential oil of T. serpyllum. The main components found in the oil were carvacrol (37.49%, γ-terpinene (10.79%, β-caryophyllene (6.51%, p-cymene (6.06%, (E-β-ocimene (4.63% and β-bisabolene (4.51%. Similarly, carvacrol (44.93%, γ-terpinene (10.08%, p-cymene (7.39% and β-caryophyllene (6.77% dominated in the oil of T. serpyllum ‘Aureus’. A total of forty three compounds were identified in this oil, representing 99.49% of the total oil content. On the basis of the obtained data it was proved that the content of 1-octen-3-ol, eucalyptol, (Z-β-ocimene, (E-β-ocimene, γ-terpinene, carvacrol methyl ether, germacrene D and β-bisabolene was significantly higher for T. serpyllum while T. serpyllum ‘Aureus’ was characterized by a significantly higher content of 3-octanone, 3-octanol, p-cymene, borneol and carvacrol. The isolated essential oils were evaluated for their antimicrobial activity against nine reference strains (Escherichia coli, Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus agalactiae, Enterococcus faecalis, Bacillus cereus, Micrococcus luteus, Proteus vulgaris and Candida albicans by the microdilution technique. Based on this test, the minimum inhibitory concentrations (MIC of essential oil were calculated. The volatile oil obtained from T. serpyllum showed the highest antimicrobial activity relative to the strain of E. coli (MIC=0.025 µL/mL and to the yeast C. albicans (MIC=0.05 µL/mL. Similarly, a significant antimicrobial activity exhibited T. serpyllum ‘Aureus’ essential oil, although the MIC values obtained in that case for E. coli and C. albicans strains were twice as high and were respectively 0.05 µ

  8. Biosynthesis, Chemical Structure, and Structure-Activity Relationship of Orfamide Lipopeptides Produced by Pseudomonas protegens and Related Species

    Ma, Zongwang; Geudens, Niels; Kieu, Nam P.; Sinnaeve, Davy; Ongena, Marc; Martins, José C.; Höfte, Monica

    2016-01-01

    Orfamide type cyclic lipopeptides (CLPs) are biosurfactants produced by Pseudomonas and involved in lysis of oomycete zoospores, biocontrol of Rhizoctonia and insecticidal activity against aphids. In this study, we compared the biosynthesis, structural diversity, in vitro and in planta activities of orfamides produced by rhizosphere-derived Pseudomonas protegens and related Pseudornonas species. Genetic characterization together with chemical identification revealed that the main orfamide com...

  9. Characterization of the Antibacterial Activity and the Chemical Components of the Volatile Oil of the Leaves of Rubus parvifolius L.

    Yongqing Cai; Xiaogang Hu; Mingchun Huang; Fengjun Sun; Bo Yang; Juying He; Xianfeng Wang; Peiyuan Xia; Jianhong Chen

    2012-01-01

    Rubus parvifolius L. (Rp) is a medicinal herb that possesses antibacterial activity. In this study, we extracted the volatile oil from the leaves of Rp to assess its antibacterial activity and analyze its chemical composition. A uniform distribution design was used to optimize the extraction procedure, which yielded 0.36% (w/w) of light yellowish oil from the water extract of Rp leaves. We found that the extracted oil effectively ...

  10. Pharmaceutical and chemical analysis of the components carrying the antiplatelet activity of extracts from allium ursinum and allium sativum

    Sabha, Dina Talat Tawfiq

    2012-01-01

    Allium sativum has a long tradition in medicine. While much is known about its potential healthy effects, nearly nothing is known about wild garlic (allium sativum, ramson), which is very common in the area of Leipzig and has been used as a herbal remedy since centuries. The goal of the present study was to assess a potential anti-platelet activity of these two allium species and to try to identify the chemical active principle. For that purpose various extracts (hydrophilic and lipophil...

  11. Chemical composition and antifungal activities of essential oils of Satureja thymbra L. and Salvia pomifera ssp. calycina (Sm.) Hayek

    Glamoclija, J.; Sokovic, M.; Vukojevic, J.; Milenkovic, I.; Griensven, van L.J.L.D.

    2006-01-01

    This work covers the chemical composition and antifungal activities of essential oils isolated from savory (Satureja thymbra) and sage (Salvia pomifera ssp. calycina) analyzed using GC/MS. The main components of S. thymbra oil were gamma-terpinene (23.2%) and carvacrol (48.5%). The main components i

  12. COMBINED USE OF A WATER-INSOLUBLE CHEMICAL DELIVERY SYSTEM AND A METABOLIC ACTIVATION SYSTEM IN WHOLE EMBRYO CULTURE

    An integrated water insoluble chemical delivery/metabolic activation/rat embryo culture system is described. In initial studies corn oil was used as the solvent and diallate as the substrate. Increasing concentrations of diallate dissolved in corn oil caused embryonic growth reta...

  13. Guidelines for active spreading during in situ chemical oxidation to remediate contaminated groundwater

    The effectiveness of in situ chemical oxidation to remediate contaminated aquifers depends on the extent and duration of contact between the injected treatment chemical and the groundwater contaminant (the reactants). Techniques that inject and extract in the aquifer to ‘ac...

  14. REDOX DISRUPTING POTENTIAL OF TOXCAST CHEMICALS RANKED BY ACTIVITY IN MOUSE EMBRYONIC STEM CELLS

    To gain insight regarding the adverse outcome pathways leading to developmental toxicity following exposure to chemicals, we evaluated ToxCast™ Phase I chemicals in an adherent mouse embryonic stem cell (mESC) assay and identified a redox sensitive pathway that correlated with al...

  15. Redox Disrupting Potential of ToxCast™Chemicals Ranked by Activity in Mouse Embryonic Stem Cells

    Little is known regarding the adverse outcome pathways responsible for developmental toxicity following exposure to chemicals. An evaluation of Toxoast™ Phase I chemicals in an adherent mouse embryonic stem cell (mESC) assay revealed a redox sensitive pathway that correlated with...

  16. Annealing effect on the particle size and chemical composition of activated carbon obtained from vacuum furnace of teak sawdust

    Armynah, B.; Tahir, D.; Jaya, N.

    2014-09-01

    Activated carbon was produced from sawdust by using physical method in a high temperature vacuum furnace without additional chemical. Fast pyrolysis process was carried out prior in fluidized a bed furnace to produce char before activation process. Experiments were conducted to investigate the influence of various process parameters such as particle size, activation temperature and activation time on the quality of the activated carbon. In addition, the chemical composition studies were done by using x-ray fluorescence (XRF) spectroscopy. The crystallite sizes were calculated by using Scherer equation based on x-ray diffraction (XRD) spectroscopy data. The pyrolysis temperature and time were varied from 600°C to 900°C and from 3 hours to 6 hours, respectively. The particle size of activated carbon was increase with increasing temperature. The composition and crystallite size of the prepared activated carbon was compared with the non-activated carbon. The results indicated that the teak sawdust carbon could be employed as a low cost alternative to produce commercial activated carbon.

  17. Annealing effect on the particle size and chemical composition of activated carbon obtained from vacuum furnace of teak sawdust

    Activated carbon was produced from sawdust by using physical method in a high temperature vacuum furnace without additional chemical. Fast pyrolysis process was carried out prior in fluidized a bed furnace to produce char before activation process. Experiments were conducted to investigate the influence of various process parameters such as particle size, activation temperature and activation time on the quality of the activated carbon. In addition, the chemical composition studies were done by using x-ray fluorescence (XRF) spectroscopy. The crystallite sizes were calculated by using Scherer equation based on x-ray diffraction (XRD) spectroscopy data. The pyrolysis temperature and time were varied from 600°C to 900°C and from 3 hours to 6 hours, respectively. The particle size of activated carbon was increase with increasing temperature. The composition and crystallite size of the prepared activated carbon was compared with the non-activated carbon. The results indicated that the teak sawdust carbon could be employed as a low cost alternative to produce commercial activated carbon

  18. Annealing effect on the particle size and chemical composition of activated carbon obtained from vacuum furnace of teak sawdust

    Armynah, B., E-mail: dtahir@fmipa.unhas.ac.id; Tahir, D., E-mail: dtahir@fmipa.unhas.ac.id; Jaya, N., E-mail: dtahir@fmipa.unhas.ac.id [Department of Physics, Hasanuddin University, Makassar 90245 (Indonesia)

    2014-09-25

    Activated carbon was produced from sawdust by using physical method in a high temperature vacuum furnace without additional chemical. Fast pyrolysis process was carried out prior in fluidized a bed furnace to produce char before activation process. Experiments were conducted to investigate the influence of various process parameters such as particle size, activation temperature and activation time on the quality of the activated carbon. In addition, the chemical composition studies were done by using x-ray fluorescence (XRF) spectroscopy. The crystallite sizes were calculated by using Scherer equation based on x-ray diffraction (XRD) spectroscopy data. The pyrolysis temperature and time were varied from 600°C to 900°C and from 3 hours to 6 hours, respectively. The particle size of activated carbon was increase with increasing temperature. The composition and crystallite size of the prepared activated carbon was compared with the non-activated carbon. The results indicated that the teak sawdust carbon could be employed as a low cost alternative to produce commercial activated carbon.

  19. Chemical characterization by GC-MS and in vitro activity against Candida albicans of volatile fractions prepared from Artemisia dracunculus, Artemisia abrotanum, Artemisia absinthium and Artemisia vulgaris

    Obistioiu, Diana; Romeo T. Cristina; Schmerold, Ivo; Chizzola, Remigius; Stolze, Klaus; Nichita, Ileana; Chiurciu, Viorica

    2014-01-01

    Background A large number of essential oils is reported to have significant activity against Candida albicans. But the different chemical composition influences the degree of their activity. The intention of this study was to investigate the chemical composition and the activity against Candida albicans of volatile oils obtained from Artemisia dracunculus, A. abrotanum, A. absinthium and A. vulgaris (Asteraceae). The aim of the study was to identify new chemical compounds that have effect aga...

  20. Chemical Structure and Immunomodulating Activities of an α-Glucan Purified from Lobelia chinensis Lour

    Xiao-Jun Li

    2016-06-01

    Full Text Available A neutral α-glucan, named BP1, with a molecular mass of approximately 9.45 kDa, was isolated from Lobelia chinensis by hot-water extraction, a Q-Sepharose Fast Flow column and Superdex-75 column chromatography. Its chemical structure was characterized by monosaccharide analysis, methylation analysis and analysis of its FT-IR, high performance gel permeation chromatography (HPGPC and 1D/2D-NMR spectra data. The backbone of BP1 consists of →6α-d-Glcp1→6,3α-d-Glcp1→(6α-d-Glcp1x-6,3α-d-Glcp1-(6α-d-Glcp1y→. The side chains were terminal α-d-Glcp1→ and α-d-Glcp1→ (6α-d-Glcp1z→4α-d-Glcp1→3α-d-Glcp1→4α-d-Glcp1→ (x + y + z = 5, which are attached to the backbone at O-3 of 3,6α-d-Glcp1. The results of the effect of BP1 on mouse macrophage cell line RAW 264.7 indicate that BP1 enhances the cell proliferation, phagocytosis, nitric oxide production and cytokine secretion in a dose-dependent manner. Because the inhibitor of Toll-like receptor 4 blocks the BP1-induced secretion of TNF-α and IL-6, we hypothesize that α-glucan BP1 activates TLR4, which mediates the above-mentioned immunomodulating effects.

  1. Chemical Structure and Immunomodulating Activities of an α-Glucan Purified from Lobelia chinensis Lour.

    Li, Xiao-Jun; Bao, Wan-Rong; Leung, Chung-Hang; Ma, Dik-Lung; Zhang, Ge; Lu, Ai-Ping; Wang, Shun-Chun; Han, Quan-Bin

    2016-01-01

    A neutral α-glucan, named BP1, with a molecular mass of approximately 9.45 kDa, was isolated from Lobelia chinensis by hot-water extraction, a Q-Sepharose Fast Flow column and Superdex-75 column chromatography. Its chemical structure was characterized by monosaccharide analysis, methylation analysis and analysis of its FT-IR, high performance gel permeation chromatography (HPGPC) and 1D/2D-NMR spectra data. The backbone of BP1 consists of →₆α-d-Glcp¹→6,3α-d-Glcp¹→(₆α-d-Glcp¹)x-6,3α-d-Glcp¹-(₆α-d-Glcp¹)y→. The side chains were terminal α-d-Glcp¹→ and α-d-Glcp¹→ (₆α-d-Glcp¹)z→₄α-d-Glcp¹→₃α-d-Glcp¹→₄α-d-Glcp¹→ (x + y + z = 5), which are attached to the backbone at O-3 of 3,6α-d-Glcp¹. The results of the effect of BP1 on mouse macrophage cell line RAW 264.7 indicate that BP1 enhances the cell proliferation, phagocytosis, nitric oxide production and cytokine secretion in a dose-dependent manner. Because the inhibitor of Toll-like receptor 4 blocks the BP1-induced secretion of TNF-α and IL-6, we hypothesize that α-glucan BP1 activates TLR4, which mediates the above-mentioned immunomodulating effects. PMID:27314319

  2. Synergistic hydrogen desorption behavior of magnesium aluminum hydride synthesized by mechano-chemical activation method

    Highlights: ► Mg(AlH4)2 could release 3.1 wt% H2 at initial temperature as low as 100 °C. ► The synergistic and mutual catalytic effects of NaAlH4 and Mg(AlH4)2 were noticed. ► In situ synchrotron XRD confirmed the two-step dehydrogenation process of Mg(AlH4)2. - Abstract: A mechano-chemical activation synthesis (MCAS) is employed to fabricate Mg(AlH4)2 via milling the precursors, specifically NaAlH4 and MgCl2. The corresponding dehydrogenation behavior of the synthesized powders is investigated. The experimental results showed that incomplete synthesis or premature dehydrogenation may occur if the milling process was not properly controlled. The hydrogen content of each synthesized powder is determined by using a thermal gravimetric analyzer (TGA). The dehydrogenation reactions of the synthesized powders are investigated by employing ex situ X-ray diffraction (XRD), in situ synchrotron XRD and differential thermal analysis (DTA). The results showed that the incompletely synthesized powder consisted of residual NaAlH4 in the synthesized Mg(AlH4)2, which demonstrated an initial dehydrogenation temperature as low as 100 °C and accompanied with a maximum amount (3.1 wt%) of H2 released below 350 °C. The mutual catalytic effect of both NaAlH4 and Mg(AlH4)2 on lowering their initial dehydrogenation temperature is confirmed.

  3. Neurodevelopmental toxicity of prenatal polychlorinated biphenyls (PCBs by chemical structure and activity: a birth cohort study

    Park Hye-Youn

    2010-08-01

    Full Text Available Abstract Background Polychlorinated biphenyls (PCBs are ubiquitous environmental toxins. Although there is growing evidence to support an association between PCBs and deficits of neurodevelopment, the specific mechanisms are not well understood. The potentially different roles of specific PCB groups defined by chemical structures or hormonal activities e.g., dioxin-like, non-dioxin like, or anti-estrogenic PCBs, remain unclear. Our objective was to examine the association between prenatal exposure to defined subsets of PCBs and neurodevelopment in a cohort of infants in eastern Slovakia enrolled at birth in 2002-2004. Methods Maternal and cord serum samples were collected at delivery, and analyzed for PCBs using high-resolution gas chromatography. The Bayley Scales of Infant Development -II (BSID were administered at 16 months of age to over 750 children who also had prenatal PCB measurements. Results Based on final multivariate-adjusted linear regression model, maternal mono-ortho-substituted PCBs were significantly associated with lower scores on both the psychomotor (PDI and mental development indices (MDI. Also a significant association between cord mono-ortho-substituted PCBs and reduced PDI was observed, but the association with MDI was marginal (p = 0.05. Anti-estrogenic and di-ortho-substituted PCBs did not show any statistically significant association with cognitive scores, but a suggestive association between di-ortho-substituted PCBs measured in cord serum and poorer PDI was observed. Conclusion Children with higher prenatal mono-ortho-substituted PCB exposures performed more poorly on the Bayley Scales. Evidence from this and other studies suggests that prenatal dioxin-like PCB exposure, including mono-ortho congeners, may interfere with brain development in utero. Non-dioxin-like di-ortho-substituted PCBs require further investigation.

  4. Essential oils from Taiwan: Chemical composition and antibacterial activity against Escherichia coli

    Po-Chen Lin

    2016-07-01

    Full Text Available The chemical compositions of seven essential oils from Taiwan were analyzed by gas chromatography-mass spectrometry. The eluates were identified by matching the mass fragment patents to the National Institute of Standards and Technology (NIST 08 database. The quantitative analysis showed that the major components of lemon verbena are geranial (26.9% and neral (23.1%; those of sweet marjoram are γ-terpinene (18.5%, thymol methyl ether (15.5%, and terpinen-4-ol (12.0%; those of clove basil are eugenol (73.6%, and β-(Z-ocimene (15.4%; those of patchouli are carvacrol (47.5% and p-cymene (15.2%; those of rosemary are α-pinene (54.8% and 1,8-cineole (22.2%; those of tea tree are terpinen-4-ol (33.0% and 1,8-cineole (27.7%; and those of rose geranium are citronellol (28.9% and 6,9-guaiadiene (20.1%. These components are somewhat different from the same essential oils that were obtained from other origins. Lemon verbena has the same major components everywhere. Tea tree, rose geranium, and clove basil have at least one major component throughout different origins. The major components and their amounts in sweet marjoram, patchouli, and rosemary vary widely from one place to another. These results demonstrate that essential oils have a large diversity in their composition in line with their different origins. The antibacterial activity of essential oils against Escherichia coli was evaluated using the optical density method (turbidimetry. Patchouli is a very effective inhibitor, in that it completely inhibits the growth of E. coli at 0.05%. Clove basil and sweet marjoram are good inhibitors, and the upper limit of their minimum inhibitory concentration is 0.1%.

  5. The Polyphenols Stability, Enzyme Activity and Physico-Chemical Parameters During Producing Wild Elderberry Concentrated Juice

    Ante Galić

    2009-12-01

    Full Text Available The influence of processing wild elderberry into concentrated juice on polyphenols (total phenols, flavonoids, non-flavonoids, anthocyanins, flavan-3-ols, hydrolysed tannins stability, activity of polyphenol oxidase (PPO and peroxidase (POD, and changes of physico-chemical parameters (total and soluble dry matter, total acidity, pH, sugars were investigated. The amounts of total phenols, flavonoids, non-flavonoids, falvan-3-ols and hydrolysed tannins were analyzed using Folin-Ciocalteu colorimetric method, while the total anthocyanins were determined by bisulphite bleaching method. Total phenols ranged from 25.87 mg/g DM to 38.87 mg/g DM. Total anthocyanins were the most abundant polyphenols in all investigated samples (raw elderberries, elderberries after blanching, elderberry juice after disintegration and pressing, concentrated elderberry juice and their concentration ranged from 13.12 mg/g DM to 25.67 mg/g DM. Other polyphenols determined in high concentration were hydrolysed tannins, followed by fl avan-3-ols, flavonoids and nonfavonoids. After blanching, the concentration of all polyphenols did not decrease significantly. After disintegration of elderberries the concentration of all polyphenols increased, probably due to inactivation of PPO and POD and better isolation of polyphenols from homogenized puree. During processing of elderberry juice into concentrated juice most polyphenols were stable. Total acidity and pH value were not changed during processing, whereas the amounts of total and reducing sugar increased after pressing and additionally after concentration. The obtained results suggest that raw elderberries as well as elderberry concentrated juice are high potential source of polyphenols especially anthocyanins.

  6. Diagnostics of microwave activated novel gas mixtures for diamond chemical vapour deposition

    Microwave plasma enhanced Chemical Vapour Deposition (CVD) has been used to grow diamond films at substrate temperatures as low as 435 deg C using CO2/CH4 gas mixtures. Molecular beam mass spectrometry (MBMS) has been used to measure simultaneously the concentrations of the dominant gas phase species present during growth, for a wide range of plasma gas mixtures (0 - 80% CH4, balance CO2). The CHEMKIN computer package has also been used to simulate the experimental results in order to gain insight into the major reactions occurring within the microwave plasma. The calculated trends for all species agree well with the experimental observations. Using these data, the model for the gas phase chemistry can be reduced to just four overall reactions. Our findings suggest that CH3 radicals are likely to be the key growth species when using CO2/CH4 plasmas and provide a qualitative explanation for the observation that diamond growth occurs within a very narrow concentration window. Diamond films have also been deposited; using both 1% CH4/H2 and 51%CH4/49%CO2 gas mixtures with various levels of H2S addition (100-5000 ppm). The former gas mixture was investigated using both microwave (MW) and hot filament (HF) activation and it was found that these two deposition techniques yield very different results. For both 1% CH4/H2 and 51%CH4/49%CO2 MW activated gas mixtures, scanning electron microscopy (SEM) observations show that the crystal quality of these films reduces with increasing H2S addition. Laser Raman and four point probe measurements showed a corresponding fall in the quality and resistivity of deposited diamond films, respectively. MBMS measurements for these S containing gas mixtures revealed significant concentrations of CS2 and CS in all of the MW plasmas that yield S-doped diamond films, whereas CS was not detected in the gas phase during HF growth. This suggests that CS may be an important intermediary facilitating S incorporation into diamond. All of these

  7. Development of nanoporous structure in carbons by chemical activation with zinc chloride.

    Rajbhandari, Rinita; Shrestha, Lok Kumar; Pokharel, Bhadra Prasad; Pradhananga, Raja Ram

    2013-04-01

    Series of activated carbons (ACs) have been prepared from Lapsi (Choerospondias axillaris) seed powder (LSP) by chemical activation with zinc chloride (ZnCI2) and the effects of ZnCl2 impregnation ratio, carbonization time, and precursor sources on the structure and properties of ACs have been systematically investigated. Carbonization was carried out at 400 degrees C and the ratio of LSP and ZnCI2 was varied from LSP:ZnCl2 = 1:0.25 (AC-0.25), 1:0.50 (AC-0.50) 1:1 (AC-1), 1:2 (AC-2), and 1:4 (AC-4). The ACs were characterized by Fourier transform-infrared (FTIR) spectroscopy, Raman scattering, X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Surface properties (effective surface areas, pore volumes, and pore size distributions) were studied by nitrogen adsorption-desorption measurements. The electrochemical and vapor sensing properties were investigated by cyclic voltammetry, and quartz crystal microbalance (QCM) method, respectively. All the ACs are amorphous materials containing oxygenated surface functional groups and having nanoporous (microporous and mesoporous) structures. We found that surface properties depend on the LSP:ZnCI2 ratio, carbonization time, and also on the precursor type. The effective surface area increased significantly with increasing LSP:ZnCI2 ratio from 1:0.25 to 1:0.5 and then remain apparently constant. However, total pore volume increased continuously with ZnCI2 ratio. Increase in the carbonization time above 4 h decreased both the surface area and pore volume. ACs prepared from bamboo and coconut shell showed better surface properties compared to AC prepared from sugarcane; surface area and pore volume of the former systems are nearly double of the later system. AC derived from LSP (AC-4) showed excellent electrochemical performance giving specific capacitance value of 328 F/g in 1 M H2SO4 solution demonstrating the potential use of this material for supercapacitor electrodes. Our

  8. Chemical composition and antimicrobial activity of Hedyosmum brasiliense Miq., Chloranthaceae, essential oil

    Karoline Kirchner

    2010-11-01

    Full Text Available Hedyosmum brasiliense Miq., Chloranthaceae, is an endemic species of Brazil, locally known as "cidrão". Although H. brasiliense is popularly used as sedative, chemical constituents of this species remains uncharacterized. This work presents the essential oil composition, obtained by distillation of the fresh leaves and from a stored sample for three months, analysed by GC-FID and GC-MS. The inhibitory effects of essential oil were tested by the agar dilution method against six bacterial species (Bacillus subtilis, Escherichia coli, Proteus mirabilis, Pseudomonas aeruginosa, Staphylococcus aureus and S. saprophyticus. In addition, six fungal species (Candida albicans, C. parapsilosis, Microsporum canis, M. gypseum, Trichophyton rubrum and T. mentagrophytes were included. Among the determined constituents, α-terpineol (10.2%, curzerene (8.9%, pinocarvone (8.4% and β-thujene (7.1% were found as the main components. The essential oil has only low activity against Gram-negative microorganisms. However, is remarkable active against Gram-positive bacteria and fungi with MIC values ranging from 0.125 to 2.5% (v/v.Óleo essencial de Hedyosmum brasiliense Miq., Chloranthaceae: composição e atividade antimicrobiana. Hedyosmum brasiliense Miq. Chloranthaceae, é uma espécie endêmica no Brasil, conhecida como "cidrão". Embora H. brasiliense seja utilizada como calmante na medicina popular, não foi ainda caracterizada quanto aos constituintes químicos. Este trabalho apresenta a composição do óleo essencial, obtido pela destilação de folhas frescas e de amostra de óleo essencial armazenada por três meses, analisadas por GC-FID e CG-MS. Os efeitos inibitórios do óleo essencial foram testados pelo método da diluição em agar, contra seis espécies de bactérias (Bacillus subtilis, Escherichia coli, Proteus mirabilis, Pseudomonas aeruginosa, Staphylococcus aureus e S. saprophyticus. Adicionalmente, seis espécies de fungos (Candida albicans

  9. Chemical Potentials, Activity Coefficients, and Solubility in Aqueous NaCl Solutions: Prediction by Polarizable Force Fields.

    Moučka, Filip; Nezbeda, Ivo; Smith, William R

    2015-04-14

    We describe a computationally efficient molecular simulation methodology for calculating the concentration dependence of the chemical potentials of both solute and solvent in aqueous electrolyte solutions, based on simulations of the salt chemical potential alone. We use our approach to study the predictions for aqueous NaCl solutions at ambient conditions of these properties by the recently developed polarizable force fields (FFs) AH/BK3 of Kiss and Baranyai (J. Chem. Phys. 2013, 138, 204507) and AH/SWM4-DP of Lamoureux and Roux (J. Phys. Chem. B 2006, 110, 3308 - 3322) and by the nonpolarizable JC FF of Joung and Cheatham tailored to SPC/E water (J. Phys. Chem. B 2008, 112, 9020 - 9041). We also consider their predictions of the concentration dependence of the electrolyte activity coefficient, the crystalline solid chemical potential, the electrolyte solubility, and the solution specific volume. We first highlight the disagreement in the literature concerning calculations of solubility by means of molecular simulation in the case of the JC FF and provide strong evidence of the correctness of our methodology based on recent independently obtained results for this important test case. We then compare the predictions of the three FFs with each other and with experiment and draw conclusions concerning their relative merits, with particular emphasis on the salt chemical potential and activity coefficient vs concentration curves and their derivatives. The latter curves have only previously been available from Kirkwood-Buff integrals, which require approximate numerical integrations over system pair correlation functions at each concentration. Unlike the case of the other FFs, the AH/BK3 curves are nearly parallel to the corresponding experimental curves at moderate and higher concentrations. This leads to an excellent prediction of the water chemical potential via the Gibbs-Duhem equation and enables the activity coefficient curve to be brought into excellent agreement

  10. Activation of Cassava Stem Biochar by Physico-Chemical Method for Stimulating Cadmium Removal Efficiency from Aqueous Solution

    Songkrit Prapagdee

    2014-06-01

    Full Text Available Removal of Cadmium (Cd from aqueous solution using biochar was considered a cost effective sorbent. Biochar quality and specification depend on its carbonization processes. In this study, the cassava stem biochars were produced at temperature of 300, 400 and 500 °C with slow pyrolysis technique. The biochar in each carbonization temperature was activated with physico-chemical treatments, pre-activated by 1.63M KOH solution then activated with second pyrolysis as same as first pyrolysis conditions. Adsorption study by using biochar adsorb Cd ion from Cd(NO32 solution by batch static method. The results indicated that the removal efficiency of activated biochar produced at pyrolysis temperature 300 °C can be increased from 10.46 to 24.88 mg/g and was selected for adsorption characteristic and biochar properties. Adsorption isotherm of non-activated and activated biochar were fitted both Langmuir and Freundlich isotherm (r2>0.95. The BET surface area of activated biochar was increased from 6.8818 to 9.4964 m2/g, while, pore size and chemical properties could be preserved. In summary, our results suggest that KOH pre-activated and second pyrolysis could increase Cd removal efficiency from aqueous solution.

  11. Effect of gamma irradiation on chemical composition, antimicrobial and antioxidant activities of Thymus vulgaris and Mentha pulegium essential oils

    The effects of gamma irradiation doses (10, 20 and 30 kGy) on chemical composition, antimicrobial and antioxidant activities of Thymus vulgaris and Mentha pulegium essential oils (EOs) have been studied. The chromatographic analysis showed that the studied EOs were constituted mainly by carvacrol for T. vulgaris and pulegone for M. pulegium. Gamma irradiation on the studied doses, affects quantitatively and not qualitatively some components of the investigated oils. This effect was dose dependent. While the antioxidant activity remains stable at any dose applied for the plants studied, the antimicrobial activity increased in the irradiated samples for gram negative bacteria and did not change for gram+bacteria. This study supports that gamma irradiation employed at sterilizing doses did not compromise the biological activities of medicinal and aromatic plants. - Highlights: • The irradiation affects quantitatively the chemical composition of EO of AMPs. • The irradiation affected significantly the antimicrobial activity. • The antimicrobial activity was more pronounced at higher doses for gram−. • The irradiation up to a dose of 30 kGy did not affect the antioxidant activities. • The irradiation at sterilizing doses did not compromise the biological activities

  12. Mentha spicata Essential Oil: Chemical Composition, Antioxidant and Antibacterial Activities against Planktonic and Biofilm Cultures of Vibrio spp. Strains

    Mejdi Snoussi; Emira Noumi; Najla Trabelsi; Guido Flamini; Adele Papetti; Vincenzo De Feo

    2015-01-01

    Chemical composition, antioxidant and anti-Vibrio spp. activities of the essential oil isolated from the aerial parts of Mentha spicata L. (spearmint) are investigated in the present study. The effect of the essential oil on Vibrio spp. biofilm inhibition and eradication was tested using the XTT assay. A total of 63 chemical constituents were identified in spearmint oil using GC/MS, constituting 99.9% of the total identified compounds. The main components were carvone (40.8% ± 1.23%) and lim...

  13. Low dose effects and non-monotonic dose responses for endocrine active chemicals: Science to practice workshop: Workshop summary

    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...... consensus was reached the robust discussions were helpful to inform both basic scientists and risk assessors on all the issues. There were a number of important ideas developed to help continue the discussion and improve communication over the next few years....

  14. Chemical Evidence for Potent Xanthine Oxidase Inhibitory Activity of Ethyl Acetate Extract of Citrus aurantium L. Dried Immature Fruits

    Kun Liu

    2016-03-01

    Full Text Available Xanthine oxidase is a key enzyme which can catalyze hypoxanthine and xanthine to uric acid causing hyperuricemia in humans. Xanthine oxidase inhibitory activities of 24 organic extracts of four species belonging to Citrus genus of the family Rutaceae were assayed in vitro. Since the ethyl acetate extract of C. aurantium dried immature fruits showed the highest xanthine oxidase inhibitory activity, chemical evidence for the potent inhibitory activity was clarified on the basis of structure identification of the active constituents. Five flavanones and two polymethoxyflavones were isolated and evaluated for inhibitory activity against xanthine oxidase in vitro. Of the compounds, hesperetin showed more potent inhibitory activity with an IC50 value of 16.48 μM. For the first time, this study provides a rational basis for the use of C. aurantium dried immature fruits against hyperuricemia.

  15. Chemical Evidence for Potent Xanthine Oxidase Inhibitory Activity of Ethyl Acetate Extract of Citrus aurantium L. Dried Immature Fruits.

    Liu, Kun; Wang, Wei; Guo, Bing-Hua; Gao, Hua; Liu, Yang; Liu, Xiao-Hong; Yao, Hui-Li; Cheng, Kun

    2016-01-01

    Xanthine oxidase is a key enzyme which can catalyze hypoxanthine and xanthine to uric acid causing hyperuricemia in humans. Xanthine oxidase inhibitory activities of 24 organic extracts of four species belonging to Citrus genus of the family Rutaceae were assayed in vitro. Since the ethyl acetate extract of C. aurantium dried immature fruits showed the highest xanthine oxidase inhibitory activity, chemical evidence for the potent inhibitory activity was clarified on the basis of structure identification of the active constituents. Five flavanones and two polymethoxyflavones were isolated and evaluated for inhibitory activity against xanthine oxidase in vitro. Of the compounds, hesperetin showed more potent inhibitory activity with an IC50 value of 16.48 μM. For the first time, this study provides a rational basis for the use of C. aurantium dried immature fruits against hyperuricemia. PMID:26950105

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

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

    2015-01-01

    underestimation of pyrethroid toxicity. This poster addresses three questions regarding the acute toxicity of pyrethroids towards the aquatic invertebrate Daphnia magna: (1) Is pyrethroid toxicity generally underestimated in the literature due to insufficiently controlled exposure levels? (2) At which chemical...

  17. Chemoselective Attachment of Biologically Active Proteins to Surfaces by Native Chemical Ligation

    Cheung, C L; de Yoreo, J J; Coleman, M; Camarero, J A

    2003-11-22

    The present work describes our ongoing efforts towards the creation of micro and nanoscaled ordered arrays of protein covalently attached to site-specific chemical linkers patterned by different microlithographic techniques. We present a new and efficient solid-phase approach for the synthesis of chemically modified long alkyl-thiols. These compounds can be used to introduce chemoselective reacting groups onto silicon-based surfaces. We show that these modified thiols can be used for creating nano- and micrometric chemical patterns by using different lithographic techniques. We show that these patterns can react chemoselectively with proteins which have been recombinantly modified to contain complementary chemical groups at specific positions thus resulting in the oriented attachment of the protein to the surface.

  18. Can phylogeny predict chemical diversity and potential medicinal activity of plants? A case study of Amaryllidaceae

    Rønsted, Nina; Symonds, Matthew RE; Birkholm, Trine;

    2012-01-01

    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 ...

  19. ANTICANCER ACTIVITY OF ISOLATED CHEMICAL CONSTITUENTS FROM MILIUSA SMITHIAE

    Chonthicha Naphong; Wilart Pompimon; Punchavee Sombutsiri

    2013-01-01

    Miliusa plants belonging to the family Annonaceae are found in Thailand and have been used as Thai traditional medicines. There have been a few previously reports on the chemical constituents of plants in this genus, describing the presence of aporphine alkaloids, terpenoids, flavonoids, phenylpropanoids, styrylpyrones, bis-styryls and homogentisic acid derivatives. Miliusa smithiae, a new species for Thailand and world, has not been studied chemical composition. The present study described p...

  20. Compound Activity Mapping: Integrating Chemical and Biological Profiling for the Functional Annotation of Natural Product Libraries

    Kurita, Kenji Long

    2015-01-01

    Natural products research has had a significant impact on human-health and our understanding of the natural world as a pillar of pharmacognosy, organic chemistry, ecology, and chemical biology. But while this science has yielded countless discoveries such as penicillin, taxol, and artimesinin and will continue to improve quality of life around the world, the idea that natural products is a panacea of chemical diversity has been challenged by problems including the endless rediscovery of known...

  1. Natural and active chemical remediation of toxic metals, organics, and radionuclides in the aquatic environment

    McPherson, G.; Pintauro, P.; O`Connor, S. [and others

    1996-05-02

    This project focuses on the chemical aspects of remediation, with the underlying theme that chemical remediation does occur naturally. Included are studies on the fate of heavy metal and organic contaminants discharged into aquatic environments; accurate assay metal contaminants partitioned into soils, water and tissue; development of novel polymeric membranes and microporous solids for the entrapment of heavy metals; and the development of hybrid chemo-enzymatic oxidative schemes for aromatics decontamination. 49 refs.

  2. Chemical Constituents from Sonneratia ovata Backer and their in vitro Cytotoxicity and Acetylcholinesterase Inhibitory Activities

    Nguyen, Thi Hoai Thu; Huu Viet Thong, Phamb; Nguyen, KimTuyen Phamc;

    2015-01-01

    Sonneratia ovata Backer, Sonneratiaceae, is a widespread plant in mangrove forests in Vietnam, Cambodia, Thailand, Indonesia. Sonneratia ovata’s chemical composition remains mostly unknown. Therefore, we now report on the structural elucidation of three new phenolics, sonnerphenolic A (1), sonner......Sonneratia ovata Backer, Sonneratiaceae, is a widespread plant in mangrove forests in Vietnam, Cambodia, Thailand, Indonesia. Sonneratia ovata’s chemical composition remains mostly unknown. Therefore, we now report on the structural elucidation of three new phenolics, sonnerphenolic A (1...

  3. Chemical Composition and Antioxidant Activity of Essential Oils of Twelve Spice Plants

    Politeo, Olivera; Jukić, Mila; Miloš, Mladen

    2006-01-01

    Chemical compositions and related total antioxidant capacities of twelve spice essential oils were analyzed. To enable a comparison of their relative antioxidant potentials, essential oils were extracted by hydrodistillation from selected spice plants and their chemical compositions were determined by the GC-MS system on two fused-silica capillary columns of different polarity. Antioxidant effectiveness was examined by four different methods: the 2,2'-diphenyl- 1-picrylhydrazyl (DPPH) radical...

  4. Chemical composition and antioxidative activity of essential oil of Thymus serpyllum L.

    Petrović Slobodan S.

    2014-01-01

    Full Text Available Wild thyme (Thymus serpyllum L. is a popular remedy regarding both traditional and conventional medicine. It is used as the antiseptic, aromatic, expectorant, stomachic, antispasmodic, carminative and preservative substance. For the purpose of this paper, wild thyme essential oil was isolated from the dried herb T. serpyllum by hydrodistillation. Original semi-industrial distillation device SP-130 performing distillation by water and steam was used for the hydrodistillation of T. serpyllum essential oils. The temperature during the hydrodistillation in the device SP-130 ranged from 100°C - 102°C at atmospheric pressure, and the whole process lasted 5 hours. The isolated essential oil is a liquid of light yellow colour and the odour characteristic of the genus Thymus. Obtained yield of essential oil was 0.08 %, with 65 components identified in the tested essential oil. The most represented chemical groups are sesquiturpene hydrocarbons with 35.1%, and oxygenated sesquiturpenes with 34.8%. The main components of essential oil of T. serpyllum were: trans-nerolidol (24.2%, germacrene D (16.0%, thymol (7.3%, δ-cadinene (3.7% and β-bisabolene (3.3%. The essential oil showed significantly better ability to neutralize DPPH free radicals (IC50 = 0.503 μL / mL compared with synthetic antioxidants BHA and BHT. Synthetic chemical compounds such as BHA and BHT are used in food industry as antioxidants due to their ability to prolong the shelf-life of foodstuffs by protecting them against deterioration caused by oxidation, such as fat rancidity, colour changes, degradation of the flavor and loss of nutrient value. In recent years, there is a considerable interest in finding natural compounds that could replace sinthetic antioxidants because of adverse toxicological reports on many synthetic compounds. Lamiaceae herbs and their essential oils or extracts application has proven to be the effective preservation agents for the extension shelf-life of

  5. Seasonal variations of antimicrobial activity and chemical composition of essential oils extracted from three Citrus limon L. Burm. cultivars.

    Settanni, L; Randazzo, W; Palazzolo, E; Moschetti, M; Aleo, A; Guarrasi, V; Mammina, C; San Biagio, P L; Marra, F P; Moschetti, G; Germanà, M A

    2014-01-01

    In order to investigate the seasonal variations of antimicrobial properties and chemical composition of essential oils (EOs), three different cultivars of Citrus limon L. Burm. spp. (Femminello Santa Teresa, Monachello and Femminello Continella) were collected at 6-week intervals, from December 2012 to April 2013, for a total of four harvests. The EOs were extracted from lemon peel by hydro-distillation. The antimicrobial activity, tested by paper disc diffusion method, was evaluated against common food-related pathogenic bacteria (Listeria monocytogenes, Staphylococcus aureus, Salmonella enterica and Enterobacter spp.). EOs were more effective against Gram-positive than Gram-negative bacteria at each collection time, but a strong strain dependence was evidenced. Monachello EOs showed the highest inhibition power. The chemical characterisation of the EOs performed by gas chromatography/mass spectrometry identified from 36 to 42 molecules. The chemical difference registered among samples and seasons may explain the different antimicrobial efficacies recorded. PMID:24443967

  6. Preparation of TiC/W core–shell structured powders by one-step activation and chemical reduction process

    Highlights: • A novel wet chemical method was used to prepare TiC/W core–shell structure powders. • TiC nanoparticles were well-encapsulated by W shells. • TiC phase was present in the interior of tungsten grains. - Abstract: In the present study, one-step activation and chemical reduction process as a novel wet-chemical route was performed for the preparation of TiC/W core–shell structured ultra-fine powders. The XRD, FE-SEM, TEM and EDS results demonstrated that the as-synthesized powders are of high purity and uniform with a diameter of approximately 500 nm. It is also found that the TiC nanoparticles were well-encapsulated by W shells. Such a unique process suggests a new method for preparing X/W (X refers the water-insoluble nanoparticles) core–shell nanoparticles with different cores

  7. Determination of photocatalytic activity in amorphous and crystalline titanium oxide films prepared using plasma-enhanced chemical vapor deposition

    Wu, Cheng-Yang; Chiang, Bo-Sheng; Chang, Springfield; Liu, Day-Shan

    2011-01-01

    Hydro-oxygenated amorphous titanium oxide (a-TiO x:OH) films were prepared by plasma-enhanced chemical vapor deposition (PECVD) using precursors of titanium tetraisopropoxide (TTIP) and oxygen. The influences of chemical states and crystal quality on the photocatalytic activity were systematically investigated in the as-deposited and post-annealed films. The degree of the photocatalytic activity was deeply correlated with the porosity related to the hydroxyl (OH) groups in the as-deposited amorphous film. The crystallized anatase structures was observed from the 200 °C-deposited a-TiO x:OH film after a post-annealing treatment at 400 °C. The photocatalytic activity related to the film with anatase structure was markedly superior to that of an amorphous film with porous structures. The larger the crystal size of the anatase structure, the higher the photocatalytic activity obtained. At elevated annealed temperatures, the inferior anatase structure due to the crystalline transformation led to a low photocatalytic activity. It was concluded that the photocatalytic activity of an amorphous TiO x film prepared using PECVD was determined by the porosity originating from the functional OH groups in the film, whereas the crystalline quality of anatase phase in the annealed poly-TiO x film was crucial to the photocatalytic activity.

  8. Partial chemical composition and antimicrobial activity of Daucus crinitus Desf. extracts

    Paolini, J.

    2010-09-01

    Full Text Available 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.La composición química de los ácidos grasos y la fracción insaponificable de raíces, hojas, y tallos de Daucus crinitus Desf. fueron establecidas utilizando cromatografía de gases (GC y cromatografía de gases-espectrometría de masas (GC-MS. La fracción de ácidos grasos de los diferentes órganos (hojas, tallos y raíces se caracterizó por el ácido láurico (17.9, 17.5 y 18.1% respectivamente y otros ácidos grasos de cadena larga (hasta C22. Diferencias cualitativas y cuantitativas se registraron entre las fracciones insaponificable de los diferentes órganos de D. crinitus. De hecho, las fracciones insaponificable de la raíz, de la hoja y del tallo mostraron cantidades altas de componentes alifáticos (83.4%, 87.2% y 91.4%, respectivamente. Los componentes monoterpénicos, diterpénicos y sesquiterpénicos solo estuvieron presentes en un pequeño porcentaje. Las propiedades antimicrobianas de los extractos de D. critinus fueron ensayadas en cuatro

  9. In vitro antiherpetic activity of a chemically sulfated galactomannan from Leucaena leucocephala seeds

    LUCY ONO

    2010-11-01

    Full Text Available

    A chemically sulfated galactomannan (LLS-2 was obtained, starting from the polysaccharide extracted from seeds of Leucaena leucocephala, which presented 15.2% sulfate and a degree of sulfation of 0.60, and its effect on the replication of Herpes simplex virus 1 (HSV-1 in Vero cells was investigated. LLS-2 showed a 93.7% inhibition of the HSV-1 replication at a concentration of 2.5 micrograms/ml, when added during its adsorption step, evaluated by the plaque reduction method, and a selectivity index higher than 1 000, suggesting that it inhibits the HSV-1 binding to the host cell, but also, in a less significant way, it showed an antiviral effect following the virus attachment step, which indicates that sulfated polysaccharides could act by more than one antiviral mechanism. Keywords: Leucaena leucocephala. Galactomannan. Sulfation. HSV-1; Antiviral activity RESUMO Obteve-se uma galactomanana quimicamente sulfatada (LLS-2 a partir de polissacarídeo extraído de sementes de Leucaena leucocephala, a qual apresentou 15.2% de sulfato e grau de derivatização de 0,60, e, seu efeito antiviral sobre a replicação do vírus Herpes simplex tipo 1 (HSV-1 em células Vero foi avaliado pela metodologia de redução do número de unidades formadoras de placas. LLS-2 apresentou 93.7% de inibição da replicação viral à concentração de 2,5 μg/ml, quando adicionado durante as etapas iniciais de replicação, com um índice de seletividade maior que 1.000, sugerindo que LLS-2 inibe a ligação de HSV-1 às células hospedeiras. Palavras-chave: Leucaena leucocephala. Galactomanana. Sulfatação. HSV-1. Atividade antiviral.

  10. Exploration of earth-abundant transition metals (Fe, Co, and Ni) as catalysts in unreactive chemical bond activations.

    Su, Bo; Cao, Zhi-Chao; Shi, Zhang-Jie

    2015-03-17

    Activation of inert chemical bonds, such as C-H, C-O, C-C, and so on, is a very important area, to which has been drawn much attention by chemists for a long time and which is viewed as one of the most ideal ways to produce valuable chemicals. Under modern chemical bond activation logic, many conventionally viewed "inert" chemical bonds that were intact under traditional conditions can be reconsidered as novel functionalities, which not only avoids the tedious synthetic procedures for prefunctionalizations and the emission of undesirable wastes but also inspires chemists to create novel synthetic strategies in completely different manners. Although activation of "inert" chemical bonds using stoichiometric amounts of transition metals has been reported in the past, much more attractive and challenging catalytic transformations began to blossom decades ago. Compared with the broad application of late and noble transition metals in this field, the earth-abundant first-row transition-metals, such as Fe, Co, and Ni, have become much more attractive, due to their obvious advantages, including high abundance on earth, low price, low or no toxicity, and unique catalytic characteristics. In this Account, we summarize our recent efforts toward Fe, Co, and Ni catalyzed "inert" chemical bond activation. Our research first unveiled the unique catalytic ability of iron catalysts in C-O bond activation of both carboxylates and benzyl alcohols in the presence of Grignard reagents. The benzylic C-H functionalization was also developed via Fe catalysis with different nucleophiles, including both electron-rich arenes and 1-aryl-vinyl acetates. Cobalt catalysts also showed their uniqueness in both aromatic C-H activation and C-O activation in the presence of Grignard reagents. We reported the first cobalt-catalyzed sp(2) C-H activation/arylation and alkylation of benzo[h]quinoline and phenylpyridine, in which a new catalytic pathway via an oxidative addition process was demonstrated

  11. Active biopolymers in green non-conventional media: a sustainable tool for developing clean chemical processes.

    Lozano, Pedro; Bernal, Juana M; Nieto, Susana; Gomez, Celia; Garcia-Verdugo, Eduardo; Luis, Santiago V

    2015-12-21

    The greenness of chemical processes turns around two main axes: the selectivity of catalytic transformations, and the separation of pure products. The transfer of the exquisite catalytic efficiency shown by enzymes in nature to chemical processes is an important challenge. By using appropriate reaction systems, the combination of biopolymers with supercritical carbon dioxide (scCO2) and ionic liquids (ILs) resulted in synergetic and outstanding platforms for developing (multi)catalytic green chemical processes, even under flow conditions. The stabilization of biocatalysts, together with the design of straightforward approaches for separation of pure products including the full recovery and reuse of enzymes/ILs systems, are essential elements for developing clean chemical processes. By understanding structure-function relationships of biopolymers in ILs, as well as for ILs themselves (e.g. sponge-like ionic liquids, SLILs; supported ionic liquids-like phases, SILLPs, etc.), several integral green chemical processes of (bio)catalytic transformation and pure product separation are pointed out (e.g. the biocatalytic production of biodiesel in SLILs, etc.). Other developments based on DNA/ILs systems, as pathfinder studies for further technological applications in the near future, are also considered. PMID:26497761

  12. Extension of in vivo half-life of biologically active peptides via chemical conjugation to XTEN protein polymer.

    Podust, Vladimir N; Sim, Bee-Cheng; Kothari, Dharti; Henthorn, Lana; Gu, Chen; Wang, Chia-wei; McLaughlin, Bryant; Schellenberger, Volker

    2013-11-01

    XTEN, unstructured biodegradable proteins, have been used to extend the in vivo half-life of genetically fused therapeutic proteins and peptides. To expand the applications of XTEN technology to half-life extension of other classes of molecules, XTEN protein polymers and methods for chemical XTENylation were developed. Two XTEN precursors were engineered to contain enzymatically removable purification tags. The proteins were readily expressed in bacteria and purified to homogeneity by chromatography techniques. As proof-of-principle, GLP2-2G peptide was chemically conjugated to each of the two XTEN protein polymers using maleimide-thiol chemistry. The monodisperse nature of XTEN protein polymer enabled reaction monitoring as well as the detection of peptide modifications in the conjugated state using reverse phase-high performance liquid chromatography (RP-HPLC) and electrospray ionization mass spectrometry. The resulting GLP2-2G-XTEN conjugates were purified by preparative RP-HPLC to homogeneity. In comparison with recombinantly fused GLP2-2G-XTEN, chemically conjugated GLP2-2G-XTEN molecules exhibited comparable in vitro activity, in vitro plasma stability and pharmacokinetics in rats. These data suggest that chemical XTENylation could effectively extend the half-life of a wide spectrum of biologically active molecules, therefore broadening its applicability. PMID:24133142

  13. Effect of age and chemical treatments on characteristic parameters for active and porous sublayers of polymeric composite membranes.

    Benavente, J; Vázquez, M I

    2004-05-15

    Changes in the transport parameters and the chemical nature of the surface of composite polyamide/polysulfone membranes due to both aging and treatment with chemical products (HCl, H(3)NO, and NaOH) have been considered. Hydraulic and salt permeability were obtained from water flow and salt diffusion measurements, respectively, and their values seem to indicate a modification in the structural parameters (porosity/thickness) of aging samples, while HCl and HNO(3) treatments will act in the opposite way. Chemical modifications in the membrane surfaces were studied by X-ray photoelectron spectroscopy (XPS), which mainly show the effect of H(3)NO and HCl on the polyamide active layer of the membranes (polyamide oxidation), but no chemical damage for that sublayer. Electrical characterization of both sublayers of the composite membranes were determined from impedance spectroscopy (IS) measurements using equivalent circuits as models, and these results indicate: (i) a strong increase of the membrane electrical resistance as a consequence of aging, mainly that associated with the active sublayer (30 times higher for an old sample than for a fresh one) and treatment with NaOH; (ii) the reduction of this effect when the samples were treated with HCl and HNO(3) solutions. Changes in the values of the electrical resistance of the composite membranes are in agreement with those obtained for permeabilities, but the electrical parameter also allows the determination of the contribution of each sublayer. PMID:15082393

  14. Chemical Composition, Antioxidant Capacity, Acetyl- and Butyrylcholinesterase Inhibitory Activities of the Essential Oil of Thymus haussknechtii Velen.

    Handan G. Sevindik

    2016-01-01

    Full Text Available The chemical composition of the essential oil from the aerial parts of Thymus haussknechtii Velen. was analyzed by using gas chromatography (GC-FID and gas chromatography-mass spectrometry (GC-MS. The major component of the essential oil was thymol (52.2%. Total phenolic content of the essential oil was determined as 132.9 µg gallic acid equivalent. The antioxidant capacity was evaluated by DPPH free radical, superoxide anion radical and hydrogen peroxide scavenging activities along with ferrous ion-chelating power test, ABTS radical cation decolorization assay and ferric thiocyanate methods. In addition to antioxidant activity, anticholinesterase activity of the essential oil was also evaluated. It exhibited inhibitory activities on AChE and BuChE which play an important role in Alzheimer’s disease, along with significant antioxidant activity.

  15. Studies on the biological effects of chemical defense mechanisms in vivo activated by low-dose irradiation

    Active oxygens produced by low-dose irradiation can induce the synthesis of proteins involved in the active oxygen reduction path and can activate the chemical self-defense mechanisms in vivo, which can alleviate the injuries caused by active oxygens themselves. The following findings suggests that it is not only by low-dose irradiation that can induce the responses described above but also by any physical and/or chemical stresses which can produce small amount of active oxygens in vivo. 1. X-irradiation with 0.5 Gy and/or water immersion and restraint induced heat shock protein (HSP)70 in rat stomach cells. HSP70 was also induced in adrenal cells by paraquat administration. 2. The SOD activity in pancreas of rat significantly increased by γ-irradiation with 0.5 Gy. 0.5 Gy irradiation preceeding the alloxan administration significantly suppressed the increase in pancreatic lipid peroxides and in blood glucose levels, degranulation in β cells, and decrease in blood insulin levels, respectively. 3. Inhalation of radon, which is a radioactive gaseous element and emits an α particle when it decays, significantly prevented the decrease in insulin levels and increase in glucose levels in blood of rabbit, respectively. (author). 85 refs

  16. Effect of storage on the chemical composition and biological activity of several popular South African medicinal plants.

    Stafford, G I; Jäger, A K; van Staden, J

    2005-02-10

    The in vitro biological activity of nine frequently used medicinal plants in South Africa was assessed and re-assessed after various lengths of storage. The plants investigated were Alepidea amatymbica, Leonotis leonurus, Drimia robusta, Vernonia colorata, Merwilla natalensis, Eucomis autumnalis, Bowiea volubilis, Helichrysum cymosum and Siphonochilus aethiopicus. Water, ethanol and hexane extracts of fresh, 90-day-old and 1-year-old material were assayed for antibacterial activity against four strains of bacteria and for COX-1 inhibition activity. TLC-fingerprints of the fresh and stored extracts were produce to document chemical changes. Alepidea amatymbica, Eucomis autumnalis, Helichrysum cymosum, Leonotis leonurus, Siphonochilus aethiopicus and Vernonia colorata were investigated further as to the effect of 1 year's storage. Elevated temperature and humidity (55 degrees C and 100% relative humidity) were used to accelerate the ageing process of Alepidea amatymbica, Leonotis leonurus and Vernonia colorata plant material for further investigation. The TLC-fingerprints indicated that there was chemical breakdown during storage in certain species. The degree of changes in biological activity and chemistry due to storage were species-specific. In general, antibacterial activity was retained in most species while COX-1 inhibition activity was lost rapidly. PMID:15652284

  17. Variation in chemical composition and acaricidal activity against Dermanyssus gallinae of four eucalyptus essential oils.

    George, David R; Masic, Dino; Sparagano, Olivier A E; Guy, Jonathan H

    2009-06-01

    The results of this study suggest that certain eucalyptus essential oils may be of use as an alternative to synthetic acaricides in the management of the poultry red mite, Dermanyssus gallinae. At a level of 0.21 mg/cm(2), the essential oil from Eucalyptus citriodora achieved 85% mortality in D. gallinae over a 24 h exposure period in contact toxicity tests. A further two essential oils from different eucalyptus species, namely E. globulus and E. radiata, provided significantly (P eucalyptus essential oils regarding their chemical compositions. There appeared to be a trend whereby the essential oils that were composed of the fewer chemical components were the least lethal to D. gallinae. It may therefore be the case that the complexity of an essential oil's chemical make up plays an important role in dictating the toxicity of that oil to pests such as D. gallinae. PMID:19089590

  18. Effect of chemicals on production, composition and antioxidant activity of polysaccharides of Inonotus obliquus.

    Xu, Xiangqun; Quan, Lili; Shen, Mengwei

    2015-01-01

    Polysaccharides are important secondary metabolites from the medicinal mushroom Inonotus obliquus. Various fatty acids, surfactants and organic solvents as cell membrane-reorganizing chemicals were investigated for their stimulatory effects on the growth of fungal mycelium and production of exopolysaccharides (EPS) and endopolysaccharides (IPS) by submerged fermentation of I. obliquus. After evaluation of 14 chemicals, oleic acid, Tween 80, and TritonX-100 were chosen for optimization of addition concentration and addition time. Among the three chemicals, 0.1% (v/v) Tween 80 gave maximum production of mycelial biomass, EPS, IPS1, and IPS2 with a increase of 16.6, 81.6, 37.7 and 18.1%, respectively, when supplemented at the early growth phase (24h after inoculation). These EPS, IPS1, and IPS2 had significantly (pobliquus supplemented with Tween 80 was evident. PMID:25797403

  19. Evaluation of gamma irradiation impact on antibacterial activity, chemical and physical characteristics of the sodium cifteraxon compound

    To investigate the effect of gamma irradiation on the solid state of ceftriaxon sodium salt (C18H16N8Na2O7S3) as a member of the third generation of cephalosporins. Solid Ceftriaxon as a pharmaceutical dosage was exposed to doses of 0, 5, 10, 15, 20, 25, and 50 kGy in 60Co package irradiator. Physical and chemical characteristics of ceftriaxon have been investigated by using UV (Ultra Violet) and IR (Infra Red) spectroscopic, pH, solubility and DSC (Differential Scanning Calorimetric) methods. Antibacterial activity of ceftriaxon was investigated using Escherichia coli ATCC 25922 as a strain of bacteria. The obtained results indicated that gamma irradiation have no effect on physical and chemical characteristics of ceftriaxon, No significant differences were found between irradiated and non-irradiated samples in the Antibacterial activity of ceftriaxon on E. Coli.(author)

  20. Chemical constituents and antimicrobial activity of the ethanol extracts obtained from the flower, leaf and stem of Salvia officinalis L.

    MIHAILO S. RISTIC

    2003-01-01

    Full Text Available In this paper a comparison of the chemical composition and antimicrobial action of the ethanol extracts from the flower, leaf and stem of the herbal species Salvia officinalis L. (Lamiaceae, originating from the southeast region of Serbia was carried out. The chemical composition of the extracts was determined by GC-FID and GC-MS analyses. Manool has the highest level of all the components (9.0–11.1 %. Antimicrobial activity was determined by the diffusion and dilution method, whereby the latter one was modified by use of cellulose discs, and it was applied for the determination of the minimal inhibitory (MIC and minimal lethal concentrations (MLC. The leaf extract has a stronger antimicrobial activity than those of the flower and stem.